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2023-11-01 | Constructing a semiconducting channel and electrodes using an identical material is a reliable method to fabricate low-cost, high-performance transistors. Wide-bandgap metal oxide semiconductors (MOSs) have been widely applied in various circuits. However, it is still a challenge to make low-cost transistors with a channel and electrodes based on identical MOSs. Here, we applied an electrospinning technique coupled with a nanowire transfer technique to fabricate high-performance, electrical-biased transistors with a one-dimensional indium tin oxide (ITO) nanowire, used as the semiconducting channel and the conducting source/drain (S/D) electrodes. The transition from a regular-conducting ITO to the newly-designed semiconducting ITO was achieved by tuning the needle diameter of the electrospinning nozzle. This method can be extended to the construction of future flexible and transparent transistors with both a channel and S/D electrodes. 金属氧化物半导体(MOSs)由于具有优异的光电学性能和稳定性, 在场效应晶体管(FETs)中具有广泛的研究价值. 然而, 以相同的MOSs材料作为FETs的沟道和源漏电极仍存在较大挑战. 本文采用静电纺丝工艺和纳米线转移技术, 以一维氧化铟锡(ITO)为主体, 构筑了低成本高性能全纳米线FETs. 通过简单调节纳米线的直径, ITO实现了由导体向半导体的转变, 基于最佳的ITO纳米线作为沟道和电极材料组建的FETs获得了较大的开关比(106)和较低阈值电压(0.6 V). 此外, 基于全静电纺丝工艺制备的增强型和耗尽型ITO纳米线FETs实现了非门逻辑及n型MOS (NMOS)电路. 该方法为未来实现柔性透明光电子器件提供了可行方案. | From conductor to semiconductor: Diameter tuning of electrospun ITO nanowire for low-cost electronics | 10.1007/s40843-023-2596-1 |
2023-11-01 | The effective fabrication of unconventional terbium selenide nanostructures was accomplished using a straightforward, quick, and environmentally benign process. The modification of Tb 2 Se 3 nanostructures was achieved through indium incorporation. X-ray diffraction analysis revealed the hexagonal symmetry of the synthesized InTbSe 3 nanostructures. Scanning electron microscopy images showed a nanosheet-like architecture for Tb 2 Se 3 and InTbSe 3 . The prepared Tb 2 Se 3 and InTbSe 3 nanostructures were also tested for their electrocatalytic oxygen evolution reaction (OER) kinetics and electrocatalytic water-splitting properties. The In-modified Tb 2 Se 3 nanostructures were superposed on the pristine material with an overpotential of 280 mV to execute the OER in an alkaline medium of 1 M KOH. It was found that InTbSe 3 has excellent promise for hydrogen evolution reaction, with a lower Tafel value of 28 mV/dec and a higher current density than the pristine Tb 2 Se 3 . The optical bandgap for Tb 2 Se 3 and InTbSe 3 was calculated to be 1.5 eV and 1.71 eV, respectively. As a photocatalyst, InTbSe 3 provides better degradation of methylene blue (98%) than Congo red dye (91%) under visible light. The UV-Vis spectroscopic results revealed the complete photocatalytic degradation of Congo red and methylene blue dye in visible light under optimized conditions. Graphical Abstract | Synthesis, Oxygen Evolution Reaction, and Dye Degradation Application of Tb2Se3 and InTbSe3 Nanostructures | 10.1007/s11664-023-10659-5 |
2023-11-01 | Abstract It is shown that the pressure and temperature of the radiating arc plasma can be determined from the measured values of the voltage on the plasma column, the discharge current and the photocurrent caused by the radiation flux of the entire volume of plasma to the photodetector. For the case of axially symmetric homogeneous arc plasma in a state of the local thermodynamic equilibrium, equations are formulated that connect the plasma parameters with the measurement results. The equation for the photocurrent is obtained from the solution of the radiation transfer equation in the arc plasma of the arbitrary optical density. The cases of electrode surfaces reflecting and absorbing electromagnetic radiation are considered. It is shown that the problem of determining the parameters of the arc plasma is reduced to solving a system of two non-linear equations with respect to pressure and temperature. The described method is used to determine plasma parameters of a high-current vacuum arc at the stage of the anode activity. The stability of the method with respect to the errors of the initial data is shown by the example of the vacuum arc plasma. | Determination of the Pressure and Temperature of the Radiating Arc Plasma from the Measured Photocurrent, Voltage and Discharge Current Values | 10.1134/S1063780X23601244 |
2023-11-01 | Features of the plasma jet formation by the glow discharge in an air flow in the system of electrodes of a low-current coaxial plasmatron are considered at an average discharge current of 100 mA and a mass air flow of 0.1 g/s. The peculiarity of experimental conditions is the positive polarity of the internal (potential) electrode of the plasmatron. Features of the discharge maintenance in the plasmatron are investigated. The technique of plasma jet diagnostics by measuring the gas temperature and the charged particle current on the special diagnostic electrode placed inside the jet is proposed. Based on the data obtained, the characteristic features of current transfer inside the jet have been obtained. The charged particle concentration inside the jet is estimated for the proposed model of current transfer. | Study of the Plasma Jet Formed by the Glow Discharge in an Air Flow at the Positive Polarity of the Potential Electrode of a Low-Current Coaxial Plasmatron | 10.1007/s11182-023-03007-x |
2023-11-01 | Intermediate transformation structures in the fusion zone of a weld joint of the X80 steel plates 8 mm thick are studied. It is shown that laser welding leads to the formation of predominantly bainite structures of various types and a small fraction of martensite in the fusion zone. The microhardness measurements in different structural phases have been carried out. The fine bainite and martensite structures have been analyzed using scanning tunnel microscopy. | Intermediate Transformation Structures in Laser Weld Joints of the X80 Steel | 10.1007/s11182-023-02998-x |
2023-11-01 | Abstract Approaches to the highly sensitive determination of low-molecular-weight fatty acids and amino acids in blood serum samples of patients diagnosed with endometriosis by gas chromatography with mass spectrometric detection (GC–MS) and HPLC with a diode array detector were proposed. Conditions for the selective determination of 23 amino acids in the form of dansyl chloride derivatives by reversed-phase HPLC with spectrophotometric detection were found, and the main factors influencing the separation parameters (pH of the mobile phase, the solvent and the buffer solution, and the gradient profile) were identified. It was shown that the traditional GC determination of metabolites in the form of silyl derivatives did not provide the required sensitivity: the high volatility of derivatives already at the stage of sample preparation led to significant losses and, as a consequence, to irreproducible results. Conditions for the determination of organic acids without derivatization using GC–MS on a polar stationary phase were optimized. A procedure for preparing blood serum for analysis (precipitation of proteins and removal of lipids) and conditions for the selective separation of analytes (temperature gradient, 70−230°C) were proposed. The developed approaches made it possible to obtain characteristic profiles of organic acids in the blood serum samples of patients with endometriosis and uterine myoma (as a comparison reference group). | Metabolic Profiling of Carboxylic Acids and Amino Acids in the Biological Fluids of Patients Diagnosed with Endometriosis Using Liquid (HPLC-UV) and Gas (GC–MS) Chromatography | 10.1134/S1061934823100040 |
2023-11-01 | The use of thin targets offers optimal conditions for accelerating protons to high energies from laser-matter interaction in the framework of the TNSA (target normal sheath acceleration) mechanism. Two-dimensional particle-in-cell (PIC) simulations were performed to investigate the effects of thickness and composition of targets in proton acceleration. We will demonstrate how proton energy increases with the target of a low atomic number Z by examining the energy spectra of the different materials He, C, and Al, whereby the maximum proton energy is obtained with a helium target. | Enhanced Proton Acceleration from a Thin Target Irradiated by Laser Pulse | 10.1007/s10812-023-01638-z |
2023-11-01 | In the developing nations like Nigeria, the science of freshwater biomonitoring is still scanty unlike developed countries. In this study, we explored the significance of using macroinvertebrates for biomonitoring of the Chanchaga River in the Lower Niger-Benue Ecoregion of Nigeria in four stations sampled for 14 months which covered both wet and dry seasons. Physico-chemical variables were analysed following standard procedures while macroinvertebrates were collected using kick sampling technique. Proportionately high values of physico-chemical variables such as nutrients, BOD and conductivity portraying increasing pollution were observed in stations 3 and 4 unlike the less disturbed stations 1 and 2. A total of 12,210 macroinvertebrates comprising of 94 taxa belonging to 11 orders and 54 families were collected during the study period. In the entire study, we recorded a total of 57.53% of macroinvertebrates during the wet season months and 42.47% in the dry season months. The canonical correspondence analysis (CCA) result revealed no marked seasonal variation in the relationship between macroinvertebrates and physico-chemical variables. Pollution tolerant taxa such as Tipula sp., Culex sp., Chironomus sp., Unionidae and Dugesia polychroa were associated with stations 3 and 4 in both wet and dry seasons. Our result from the analysis of similarity (ANOSIM) revealed that station 4 had the highest similarities in terms of macroinvertebrates distribution, while the result of the similarity percentage (SIMPER) indicated 91.73% dissimilarity in macroinvertebrates taxa between stations 1 and 4. This confirmed one of our hypotheses which states that macroinvertebrates will respond differentially to pollution gradients across the stations sampled. We concluded that the present study will serve as vista to biomonitoring of freshwater systems in the Afrotropical region. However, the study did not unveil the functional ecology of the macroinvertebrate assemblage. We therefore recommend that a combination of structural and functional ecology of freshwater systems should be explored in future studies. | Preliminary studies on macroinvertebrate biomonitoring of freshwater systems in the Afrotropics: a case study of the Chanchaga River in the Lower Niger-Benue Ecoregion of Nigeria | 10.1007/s11756-023-01445-z |
2023-11-01 | Globally renewable energy sources play a vital role in future energy production. Heat transfer and generation of drag are the two crucial elements in the global energy consumption chain. In this review analysis, we have emphasized how to improve these two areas to extract most of the energy available in nature and to enhance convective internal heat transfer for effective cooling of applications in automobiles, aerospace, electronics, heating, and cooling devices. Heat transfer enhancement achieved in many ways and using riblets is one of the methods of implementing passive techniques. Riblet applications in wind turbines employed with specially created microstructured surfaces and provide a variety of benefits which include a reduction in drag over a wind turbine especially operating at low Reynolds number. The overall drag reduction over a wind turbine depends on height, shape and whether it is fully or partially applied on aerofoil surfaces. Earlier studies proved that optimum drag reduction was achieved by employing riblets with varied geometry along the aerofoil. This analysis discusses the influence of riblets used in wind, hydro and gas turbines, which follows a comparison of heat transfer and aerodynamic effects. | Review analysis on riblets used in thermal applications and wind turbines | 10.1007/s10973-023-12494-6 |
2023-11-01 | Abstract — The article addresses general matters concerned with the occurrence of low-frequency vibration (LFV) in turbine units. It is pointed out that, despite the level of knowledge that has been achieved in regard to LFV, it still arises from time to time in power plant turbine units. Along with LFV caused by aero- and hydrodynamic excitation, LFV can also bear a subharmonic pattern. It is emphasized that the measures taken to remove LFV depend on the LFV occurrence origin. The article presents LFV occurrence and removal examples, including those relating to the use of honeycomb seals in high-pressure cylinders. With honeycomb seals, decreased sizes of channels and an increased channel component of overshroud forces caused by aerodynamic excitation are typically observed. It is pointed out that, in some cases that involve rotor rubbing against the stator, a multicomponent LFV with subharmonic and self-oscillation components is observed. It is shown that the regulatory documents do not contain criteria for estimating a multicomponent vibration in the low-frequency band. It is pointed out that multicomponent LFV can be a diagnostic indicator pointing to rubbing of the rotor against the babbit or seals. Recommendations on removing LFV of various origins are suggested. A diagnostic table that helps determine factors causing the LFV and that produces recommendations on increasing the turbine units operational reliability is given. It is stated for the first time that the turbine thrust bearing can behave as a source of oil excitation. It is also noted that the conditions under which a self-oscillation type LFV occur and its suppression methods should differ from the methods for suppressing self-excited LFV of a subharmonic nature. | Some Features Relating to the Occurrence of Low-Frequency Vibration in Large Steam Turbines and Methods for Removing It | 10.1134/S0040601523110095 |
2023-11-01 | Abstract The whole-cell catalysis strategy of alpha-ketoglutaric acid (α-KG) production from L-glutamic acid (L-Glu) using recombinant Escherichia coli , in which L-glutamate oxidase (LGox) was over-expressed, has replaced the traditional chemical synthesis strategy. However, large amounts of toxic by-product, H 2 O 2 , should be eliminated through co-expressing catalase (Cat), thus severely increasing burden in cells. To efficiently and economically produce α-KG, here, the genes SpLGox (from Streptomyces platensis NTU3304) and SlCat (from Streptomyces lividans TK24) were inserted into the low-dosage-IPTG (Isopropyl β-D-Thiogalactoside) inducible expression system, constructed in our previous work, in E. coli , respectively. Besides, a double-strain catalysis system was established and optimized to produce α-KG, and the productivity of α-KG was increased 97% compared with that through single strain catalysis. Finally, a double-strain cultivation strategy was designed and employed to simplify the scale-up fermentation. Using the optimized whole-cell biocatalyst conditions (pH 7.0, 35 °C), majority of the L-glutamic acid was transformed into α-KG and the titer reached 95.4 g/L after 6 h with the highest productivity at present. Therefore, this strategy may efficiently and cost-effectively produce α-KG, enhancing its potential for industrial applications. Key points • SpLGox and SlCat were over-expressed to catalyze L-Glu to α-KG and eliminate by-product H 2 O 2 , respectively. • Double-strain cultivation and catalysis system can efficiently and cost-effectively produce α-KG from L-Glu. | Efficient production of α-ketoglutaric acid using an economical double-strain cultivation and catalysis system | 10.1007/s00253-023-12757-0 |
2023-11-01 | Reconfigurable intelligent surface (RIS) is an emerging technology to improve the spectral efficiency of wireless communication systems. However, the high complexity of beam design and the non-negligible overhead associated with RIS limit the number of elements that can be deployed in practice. In this paper, we investigate the downlink communications of irregularly deployed intelligent reflecting surfaces that assist non-orthogonal multiple access (NOMA) systems. To address this challenge, we propose a novel four-step resource allocation algorithm. Specifically, we first obtain a sub-optimal solution for the sparse deployment of RIS elements using a Simulated Annealing Algorithm. We then solve the power allocation problem by employing an integer optimization algorithm that continuously iterates the immobile point. To simplify and optimize the reflection coefficient matrix, we propose a construction inequality algorithm. Finally, we optimize the channel assignment using a genetic algorithm. The simulation results demonstrate that the proposed irregular RIS-assisted NOMA system outperforms the traditional RIS-assisted orthogonal multiple access system, with a maximum throughput increase of approximately 30%. | Throughput maximization for irregular reconfigurable intelligent surface assisted NOMA systems | 10.1186/s13634-023-01076-1 |
2023-11-01 | Abstract The effect of ZrO 2 particles with 0.1, 0.2 and 0.3 wt % was studied on the corrosion behavior of zinc coating with nano and micro sizes. In this case, the specimens were immersed in a zinc bath for 6 s. The mechanical, structural properties and corrosion behavior of coatings were determined by Vickers’s hardness, bending, porosity and thickness measurement tests, SEM and FE-SEM, Open circuit potential, Salt spray, Polarization and Impedance test. The obtained results showed that the reduced of thickness, surface porosity and roughness of coating, increased the adhesion of coating due to the incorporation of oxide particles and increased the hardness of coating. Additionally, increase in the polarization resistance and reduction of corrosion current density and reduced the corrosion rate of the galvanized coating, which confirmed with impedance test. Also, the addition of oxide particle, decreased the thickness of brittle phases such as gamma and delta in the coating. Because, the formation of fine grain and distribution of oxide particle in the coating, prevented the accumulation and changed the coating texture, improved the corrosion resistance and mechanical properties of coating. Consequently, the electrochemical analysis revealed the desirable amount of corrosion resistance for the coating containing 0.3 wt % of nano ZrO 2 , which showed about 99/89% reduction in corrosion rate. | Improve the Corrosion Behavior of Galvanized Coating by Incorporation of ZrO2 Particles Using a Hot-Dip Method | 10.1134/S2070205123700946 |
2023-11-01 | Forest fire is considered as a natural disaster and major potential threat in many parts of the world. Due to the lack of a comprehensive study in terms of the synoptic conditions of the fire incident in the studied area, the present study was conducted in order to identify the predominant synoptic patterns of fire occurrence in the western Alborz Mountains. To this end, first, the days of fire were obtained from the Department of Natural Resources of Gilan Province and the product (MCD14) Modis sensor (2007–2020). In order to determine atmospheric synoptic patterns, atmospheric maps were obtained from the NCEP site on all fire days. Totally, 240 fires occurred. Among the months of the year, July, August, and December had the highest incidence of fires. Based on the fires that occurred, three predominant synoptic patterns had the highest frequency of fires, including (1) Saudi-African high pressure dominant in the hot and cold seasons of the year, with three forms of omega blocking (16.5%), ridge (24.8%), and intrusion (22.2%), in total with a frequency of 63.5%; (2) European Migrant high-pressure system intrusion dominant in the hot period of the year, with a frequency of 21.7%; and (3) subpolar low pressure, which is generally dominant during the cold period of the year and responsible for about 14.8% of the fires in the region. Therefore, the most common occurrence of natural fires in the region is due to the high-pressure influence of Arabia and Africa in the hot and cold periods of the year. | Investigation of synoptic patterns of fire occurrence in the forests of the western Alborz Mountains | 10.1007/s00704-023-04625-8 |
2023-11-01 | One can safely say that the pioneering work of Dr. Ulrich Kogelschatz and his team on the physics and chemistry of the dielectric barrier discharge was foundational and remain of great relevance to the present day. Kogelschatz and his team made some of the early high-resolution measurements of the current pulses associated with filaments and conducted simulations to elucidate the chemical processes taking place in DBD plasmas. On the engineering/technology side, he contributed to the development of DBD-based excimer lamps, to the optimization of DBD-based ozone generators and to many other advancements. His numerous papers on the physics and applications of DBD have educated a generation of researchers involved with such devices. I consider myself one of those students who learned a lot from him, both from his writings and from personal interaction. In this perspective, I first briefly summarize the working of barrier discharges and some of Kogelschatz’s contributions to this field. Then, I highlight some of the most valuable interactions I had the privilege to have with him, who I considered to be a mentor and a dear friend for many years. Please note that I use the formal title “Dr. Kogelschatz” in the title and sub-titles but in the text, I use Ulrich (or Uli) as that is how I addressed him in person. | The Dielectric Barrier Discharge and the Start of a Beautiful Friendship: Personal Remembrance of Dr. Ulrich Kogelschatz | 10.1007/s11090-023-10313-2 |
2023-11-01 | Abstract The mechanism of occurrence of spontaneous self-sustained currents in a multiwire proportional chamber from the experiment at the Large Hadron Collider has been considered. Atomic force microscopy, Rutherford backscattering, and Raman spectroscopy on the copper foil of the chamber cathode revealed the formation of nanocarbon structures and their fluorinated compounds, which are well known as low-threshold sources of field emission of electrons. | Nanostructured Emission Current Sources in Multiwire Proportional Chambers | 10.3103/S1062873823703999 |
2023-11-01 | Abstract Chitosan derivates with varying degrees of polymerization (DP) have attracted great concern due to their excellent biological activities. Increasing the abundance of chitosanases with different degradation modes contributes to revealing their catalytic mechanisms and facilitating the production of chitosan derivates. However, the identification of endo-chitosanases capable of producing chitobiose and D-glucosamine (GlcN) from chitosan substrates has remained elusive. Herein, an endo-chitosanase (CsnCA) belonging to the GH46 family was identified based on structural analysis in phylogenetic evolution. Moreover, we demonstrate that CsnCA acts in a random endo-acting manner, producing chitosan derivatives with DP ≤ 2. The in-depth analysis of CsnCA revealed that (GlcN) 3 serves as the minimal substrate, undergoing cleavage in the mode that occupies the subsites − 2 to + 1, resulting in the release of GlcN. This study succeeded in discovering a chitosanase with distinctive degradation modes, which could facilitate the mechanistic understanding of chitosanases, further empowering the production of chitosan derivates with specific DP. Graphical Abstract Key points • Structural docking and evolutionary analysis guide to mining the chitosanase. • The endo-chitosanase exhibits a unique GlcN-producing cleavage pattern. • The cleavage direction of chitosanase to produce GlcN was identified. | Structure-based mining of a chitosanase with distinctive degradation mode and product specificity | 10.1007/s00253-023-12741-8 |
2023-11-01 | For in-depth investigation of the effect of low-frequency and DC remelting on the cleanliness of electroslag ingot, laboratory experiments were performed with different current densities and slag compositions to analyze the variation of oxygen content and inclusions in electroslag ingots. When 70% CaF 2 + 30% Al 2 O 3 binary slag is used for remelting, the current density has different effects on the cleanliness of electroslag ingots with different power supply modes. At the power frequency of 2 Hz, the oxygen content and the number of inclusions in the electroslag ingot increase significantly with the increase in remelting current density. By contrast, when consumable electrode connected to cathode (DCSP) or consumable electrode connected to anode (DCRP) is employed, the current density has little influence on ingot cleanliness. At the same current density, DCSP remelting has a more adverse effect on ingot cleanliness compared with DCRP remelting. Compared with the use of 70% CaF 2 + 30% Al 2 O 3 binary slag, using 60% CaF 2 + 20% Al 2 O 3 + 20% CaO ternary slag significantly reduces the oxygen content and the number of inclusions in electroslag ingots, regardless of whether low-frequency or DC electroslag remelting occurs. The increase in oxygen and inclusions in electroslag ingot is caused by the electrolysis of Al 2 O 3 in the slag pool. The increased inclusions mainly involve Al 2 O 3 or Al-containing oxides with small size. As regards the power supply mode, low frequency, DCRP, and DCSP promote the electrolysis of Al 2 O 3 in the slag pool. From the perspective of remelting slag composition, the slag with lower Al 2 O 3 content can reduce the pollution of electrolysis on electroslag ingot. | Effect of slag composition and current density on ingot cleanliness during low-frequency/DC electroslag process | 10.1007/s42243-023-01035-y |
2023-11-01 | Abstract Results of experiments on injection of dense plasma clouds created by a small-scale coaxial generator into vacuum and large-volume background plasma in an ambient magnetic field are presented. The regime of an “infinite” background medium that allows studying the plasma-cloud dynamics on the scale of about one meter in the directions perpendicular and parallel to a quasi-uniform magnetic field is realized on “Krot” plasma device. The dynamics of the diamagnetic cavity appearing upon magnetic-field expulsion by a plasma blob, the electromagnetic noise appearing in the cavity, along with the evolution of plasma-cloud structure during injection and at the stage of its decay, were studied. It is demonstrated that the key properties of the cloud dynamics that are typical of the active space and high-energy laboratory experiments, including complete expulsion of the magnetic field from the cloud and development of the flute instability at its boundary, are reproduced at low injection speed (below 30 km/s) and low plasma energy (on the order of 0.1 J). | Dynamics of a Plasma Cloud Generated by a Compact Coaxial Gun upon Expansion into Vacuum and Large-Volume Background Plasma in an External Magnetic Field | 10.1134/S1063780X23601141 |
2023-11-01 | Improving radiation effect on tumor cells using radiosensitizers is gaining traction for improving chemoradiotherapy. This study aimed to evaluate copper nanoparticles (CuNPs) synthesized using chrysin as radiosensitizer with γ-radiation on biochemical and histopathological approaches in mice bearing Ehrlich solid tumor. CuNPs were characterized with irregular round sharp shape with size range of 21.19–70.79 nm and plasmon absorption at 273 nm. In vitro study on MCF-7 cells detected cytotoxic effect of CuNPs with IC 50 of 57.2 ± 3.1 μg. In vivo study was performed on mice transplanted with Ehrlich solid tumor (EC). Mice were injected with CuNPs (0.67 mg/kg body weight) and/or exposed to low dose of gamma radiation (0.5 Gy). EC mice exposed to combined treatment of CuNPs and radiation showed a marked reduction in tumor volume, ALT and CAT, creatinine, calcium, and GSH, along with elevation in MDA, caspase-3 in parallel with inhibition of NF-κB, p38 MAPK, and cyclin D 1 gene expression. Comparing histopathological findings of treatment groups ends that combined treatment was of higher efficacy, showing tumor tissue regression and increase in apoptotic cells. In conclusion, CuNPs with a low dose of gamma radiation showed more powerful ability for tumor suppression via promoting oxidative state, stimulating apoptosis, and inhibiting proliferation pathway through p38MAPK/NF-κB and cyclinD1. | Chrysin Encapsulated Copper Nanoparticles with Low Dose of Gamma Radiation Elicit Tumor Cell Death Through p38 MAPK/NF-κB Pathways | 10.1007/s12011-023-03596-1 |
2023-11-01 | Manganese(II) borate glasses with chemical composition (55 − x )B 2 O 3 -25Li 2 O-10Na 2 O-5CaO-3SrO-2Al 2 O 3 - x MnO 2 : x = 0.0 (G1)–2.0 (G5) mol.% were successfully prepared using the traditional melt quenching route, and the physical properties, optical characteristics, and Fourier transform infrared (FTIR) spectroscopy were investigated. The density ( D s ) increased from 2.367 g/cm 3 to 2.510 g/cm 3 , and the molar volume ( V m ) decreased from 25.31 cm 3 /mol to 24.01 cm 3 /mol. The average boron–boron distance ‹ d B–B › decreased from 3.60 nm to 3.54 nm, whereas the ion concentration ( N Mn ) increased from 0.118 × 10 20 ions/cm 3 to 5.02 × 10 20 ions/cm 3 as the MnO 2 increased from 0.0 mol.% to 2 mol.% in the glass network. The packing density ( P d ) values increased from 0.49 to 0.51, but the free volume V f enhanced from 0.278 × 10 16 g/mol cm 2 to 3.38 × 10 16 g/mol cm 2 as MnO 2 increased. FTIR spectroscopy showed the change in internal structure and confirmed that [BO 3 ] units favor a coordination change to [BO 4 ] over creating non-bridging oxygen (NBO). The optical band gap ( E g ) decreased with increasing MnO 2 content from 0.0 mol.% to 0.4 mol.%, then increased with increasing MnO 2 content from 1 mol.% to 2 mol.%. Urbach energy (Δ E ) values between 0.242 eV and 0.529 eV were obtained by increasing MnO 2 in the glass matrix . | Physical, Structural, and Optical Characteristics of Manganese Ion-Containing Low-Melting Borate Glasses | 10.1007/s11664-023-10649-7 |
2023-11-01 | Abstract DFT modeling of hydrogen sorption on graphene and C 2 N monolayers using the SIESTA and VASP packages demonstrates the need for optimizing the pseudo-atomic orbital basis set and calculating the counterpoise correction to the basis set superposition error for H 2 binding energy. The use of pseudo-atomic orbitals reduces the H 2 -monolayer distance by 10%, relative to plane wave data. The optimized pseudo-atomic orbital parameters for a C 2 N monolayer can be used to further investigate this material. | Basis Set Superposition Error: Effects of the Boys‒Bernardi Correction on the DFT Modeling of Hydrogen Sorption on Low-Dimensional Carbon Nanomaterials | 10.3103/S1062873823703860 |
2023-11-01 | Objective Nanoparticles (NPs) hold a great promise in combating rheumatoid arthritis, but are often compromised by their toxicities because the currently used NPs are usually synthesized by chemical methods. Our group has previously fabricated Ångstrom-scale silver particles (AgÅPs) and demonstrated the anti-tumor and anti-sepsis efficacy of fructose-coated AgÅPs (F-AgÅPs). This study aimed to uncover the efficacy and mechanisms of F-AgÅPs for arthritis therapy. Methods We evaluated the efficacy of F-AgÅPs in collagen-induced arthritis (CIA) mice. We also compared the capacities of F-AgÅPs, the commercial AgNPs, and the clinical drug methotrexate (MTX) in protecting against K/BxN serum-transfer arthritis (STA) mice. Moreover, we evaluated the effects of F-AgÅPs and AgNPs on inflammation, osteoclast formation, synoviocytes migration, and matrix metalloproteinases (MMPs) production in vitro and in vivo. Meanwhile, the toxicities of F-AgÅPs and AgNPs in vitro and in vivo were also tested. Results F-AgÅPs significantly prevented bone erosion, synovitis, and cartilage damage, attenuated rheumatic pain, and improved the impaired motor function in mouse models of CIA or STA, the anti-rheumatic effects of which were comparable or stronger than AgNPs and MTX. Further studies revealed that F-AgÅPs exhibited similar or greater inhibitory abilities than AgNPs to suppress inflammation, osteoclast formation, synoviocytes migration, and MMPs production. No obvious toxicities were observed in vitro and in vivo after F-AgÅPs treatment. Conclusions F-AgÅPs can effectively alleviate arthritis without notable toxicities and their anti-arthritic effects are associated with the inhibition of inflammation, osteoclastogenesis, synoviocytes migration, and MMPs production. Our study suggests the prospect of F-AgÅPs as an efficient and low-toxicity agent for arthritis therapy. | Ångstrom-scale silver particles ameliorate collagen-induced and K/BxN-transfer arthritis in mice via the suppression of inflammation and osteoclastogenesis | 10.1007/s00011-023-01778-0 |
2023-11-01 | Liquid biopsy research on Low-Grade gliomas (LGG) has remained less conspicuous than that on other malignant brain tumors. Reliable serum markers would be precious for diagnosis, follow- up and treatment. We propose a clinical utility score (CUS) for biomarkers in LGG that mirrors their clinical usefulness. We conducted a PRISMA review. We examined each biomarker classifying them by CUS and Level of Evidence (LOE). We identified four classes of biomarkers: (1). Circulating protein—(a) vitronectin discriminates LGG from HGG (Sn:98%, Sp:91%, CUS: 3, LOE: III), (b) CTLA-4 discriminates LGG from HGG, (cutoff: 220.43 pg/ml, Sn: 82%, Sp: 78%, CUS:3, LOE:III), (c) pre-operative TGF b1 predict astrocytoma (cutoff: 2.52 ng/ml, Sn: 94.9%, Sp: 100%, CUS:3, LOE:VI). (2). micro-RNA (miR)—(a) miR-16 discriminates between WHO IV and WHO II and III groups (AUC = 0.98, CUS:3, LOE: III), (b) miR-454-3p is higher in HGG than in LGG (p = 0.013, CUS:3, LOE: III), (c) miR-210 expression is related to WHO grades (Sn 83.2%, Sp 94.3%, CUS: 3, LOE: III). (3). Circulating DNA—(a) IDH1R132H mutation detected in plasma by combined COLD and digital PCR (Sn: 60%, Sp: 100%, CUS: 3, LOE: III). 4. Exosomes—(a) SDC1 serum levels could discriminate GBM from LGG (Sn: 71%, Sp: 91%, CUS: 2C, LOE: VI). Our investigation showed that miRs appear to have the highest clinical utility. The LOE of the studies assessed is generally low. A combined approach between different biomarkers and traditional diagnostics may be considered. Graphical Abstract We identified four main classes of biomarkers produced by LGG. We examined each biomarker, classifying them by clinical utility score (CUS) and level of evidence (LOE). Micro-RNA (miRs) appears to have the highest CUS and LOE. | Liquid Biopsy in Low-Grade Glioma: A Systematic Review and a Proposal for a Clinical Utility Score | 10.1007/s10571-023-01406-9 |
2023-11-01 | Abstract The reaction of adamantan-1-ol with lower alcohols (methanol, ethanol) in the presence of water and an equimolar amount of CuBr 2 (with respect to adamantan-1-ol) at 220°C for 4 h gives adamantane in a high yield. ( E )-(Prop-1-en-1-yl)adamantane was obtained in a high yield from adamantan-1-ol and isopropanol under similar conditions but in the absence of water. | Reaction of Adamantan-1-ol with Lower Alcohols in the Presence of CuBr2 | 10.1134/S1070363223140311 |
2023-11-01 | The development of a low-carbon economy has been the focus of attention from all walks of life in recent years. Using data from 41 cities in the Yangtze River Delta (YRD) from 2005 to 2019, this study constructed a low-carbon economic development coupling and coordination degree model and indicator system to measure the synergistic effect. Starting from the resource, economy, society, and innovation system, it was found that the coupling degree of low-carbon economic development in the YRD region has increased steadily. Generally, it is in a running-in period, and the improvement rate shows a high trend in the west and a low trend in the east. Also, the YRD is in a moderate incoordination stage, but the synergy effect has improved. Among these cities, Shanghai and Hangzhou had higher synergy efficiency in 2019 compared to other cities. Regarding city heterogeneity, the synergy effect of non-resource-based cities is significantly higher than that of resource-based cities but a narrowed gap. The research provides a theoretical and factual basis for the design of a path toward low-carbon economic development in the YRD region. | Modeling the city-level synergistic effect of low-carbon economic development in China’s Yangtze River Delta | 10.1007/s11356-023-30338-6 |
2023-11-01 | Compressible vortex rings have been widely investigated for decades under ambient atmospheric conditions, and understanding this transient phenomenon is important for improving the thrust vector and avoiding surface impingement and contamination. However, how the vortex ring behaves in a reduced pressure environment remains unknown. This work provides schlieren imaging and pressure measurement results of the vortex ring when the environmental pressure is lower than 1 atm. The basic structure of the compressible vortex ring in low-pressure environments has been captured. The reduced environmental pressure will degenerate the internal flow structure, including the shock wave, the CRVRs, and the vortices due to the Kelvin–Helmholtz instability, which is consistent with the conclusion of previous numerical work. The vortex ring is confirmed to exist when the environmental pressure is approximately 1.0 kPa. | Vortex Ring Formation Following Shock Wave Diffraction in Low-Pressure Environments | 10.1007/s10494-023-00486-3 |
2023-11-01 | Low salinity tidal wetlands (LSTW) are vulnerable to sea level rise and saltwater intrusion, thus their carbon sequestration capacity is threatened. However, the thresholds of rapid changes in carbon dynamics and biogeochemical processes in LSTW due to changes in hydroperiod and salinity regime remain unclear. In this study, we examined the effects of soil porewater salinity and water level on changes in net primary productivity (NPP) and greenhouse gas fluxes [GHG: methane (CH 4 ), nitrous oxide (N 2 O), and carbon dioxide (CO 2 )] in LSTW using a wetland biogeochemistry model, Tidal Freshwater Wetland Denitrification and Decomposition (TFW-DNDC). TFW-DNDC was run with a series of combinations of soil salinities (0.1, 0.5, 1, 2, 4, 6, 8, 10 psu) and water levels relative to soil surface (-30, -20, -10, -5, 0, 5, 10, 20, 30 cm) for tidal forest and oligohaline marsh sites along the Savannah River and Waccamaw River, USA. Our results indicate that soil salinity and water level have antagonistic effects on CH 4 emissions and synergistic effects on CO 2 release. A soil salinity of 2-3 psu is the tipping point for the ecosystem level functional changes (e.g., NPP and CH 4 emissions) in LSTW. There are negative and nonlinear responses (NPP and CH 4 emission) to soil salinity. Furthermore, a soil water level from 10 cm below to 10 cm above the surface is a critical range in which biogeochemical processes respond strongly to hydrological changes. The presence of nonlinear tipping points in LSTW has large implications for understanding and predicting the effects of climate change on coastal wetland blue carbon storage and ecosystem dynamics. | Soil Salinity and Water Level Interact to Generate Tipping Points in Low Salinity Tidal Wetlands Responding to Climate Change | 10.1007/s12237-023-01243-5 |
2023-11-01 | Capillary electrophoresis mass spectrometry (CE-MS) is an emerging analytical tool for microscale biological sample analysis that offers high separation resolution, low detection limit, and low sample consumption. We recently developed a novel microsampling device, “spray-capillary,” for quantitative low-volume sample extraction (as low as 15 pL/s) and online CE-MS analysis. This platform can efficiently analyze picoliter samples (e.g., single cells) with minimal sample loss and no additional offline sample-handling steps. However, our original spray-capillary-based experiments required manual manipulation of the sample inlet for sample collection and separation, which is time consuming and requires proficiency in device handling. To optimize the performance of spray-capillary CE-MS analysis, we developed an automated platform for robust, high-throughput analysis of picoliter samples using a commercially available CE autosampler. Our results demonstrated high reproducibility among 50 continuous runs using the standard peptide angiotensin II (Ang II), with an RSD of 14.70% and 0.62% with respect to intensity and elution time, respectively. We also analyzed Ang II using varying injection times to evaluate the capability of the spray-capillary to perform quantitative sampling and found high linearity for peptide intensity with respect to injection time ( R 2 > 0.99). These results demonstrate the capability of the spray-capillary sampling platform for high-throughput quantitative analysis of low-volume, low-complexity samples using pressure elution (e.g., direct injection). To further evaluate and optimize the automated spray-capillary platform to analyze complex biological samples, we performed online CE-MS analysis on Escherichia coli lysate digest spiked with Ang II using varying injection times. We maintained high linearity of intensity with respect to injection time for Ang II and E. coli peptides ( R 2 > 0.97 in all cases). Furthermore, we observed good CE separation and high reproducibility between automated runs. Overall, we demonstrated that the automated spray-capillary CE-MS platform can efficiently and reproducibly sample picoliter and nanoliter biological samples for high-throughput proteomics analysis. Graphical abstract | An automated spray-capillary platform for the microsampling and CE-MS analysis of picoliter- and nanoliter-volume samples | 10.1007/s00216-023-04870-w |
2023-11-01 | The electrostatic properties of clay (or other charged) mineral surfaces play a significant role in the fate, transport, persistence, and remediation of subsurface contaminant plumes. This study presents a stochastic assessment of the impact and relevance of microscale electrostatic effects on macroscopic, field-scale contaminant transport in heterogeneous groundwater systems involving spatially distributed clay zones. We present Monte Carlo simulations in two-dimensional heterogeneous fields, comprising heterogeneous distributions of physical (i.e., hydraulic conductivity, porosity, tortuosity) and electrostatic (i.e., surface charge) properties, and compare scenarios with different combination and extent of physical and electrostatic processes. The simulations were performed with the multi-continua based reactive transport code, MMIT-Clay, and considering an explicit treatment of the diffuse layer processes. The results reveal that the microscopic electrostatic mechanisms within clay’s diffuse layer can significantly accelerate or retard a particular contaminant depending on its charge, leading to considerably different solute breakthroughs and mass loading/release behaviors in low permeability inclusions. Furthermore, we show that such variations in the macroscale transport behavior, solely driven by charge interactions, are statistically significant over the ensembles of Monte Carlo realizations. The simulations also demonstrate that the omission of electrostatic processes, which is still a common practice in subsurface hydrology, can lead to substantial over- or underestimation of contaminant migration. | Relevance of charge interactions for contaminant transport in heterogeneous formations: a stochastic analysis | 10.1007/s00477-023-02514-0 |
2023-11-01 | Ibuprofen is a pharmaceutical that is commonly used to reduce inflammation and to treat headaches. A thin-layer chromatographic method combined with simple and inexpensive digital imaging is proposed for the determination and quantification of ibuprofen. The recommendations of the standard pharmacopoeia were followed with the addition of a minimal spotting method as a local calibration curve ( n = 3) and comparison with a spotted sample. Images were acquired using a smartphone and then converted to greyscale using Fiji, an open-source image analysis software. The peak area and density of each spot was then calculated using a densitometric principle. To analyse the present image data, several images were taken with different filters. Using a calibration curve ranging in the range of 3 to 5 mg/mL, linearity could be determined across the subjected images ( R 2 ranging from 0.984 to 0.996), with a mean accuracy of 99.9 ± 2.20% and RSD of 2.20%. The method studied, using smartphone imaging and open-source software (Fiji), offered a simple and inexpensive application for the quantification of ibuprofen in pharmaceuticals, applicable to preliminary studies and curricula. Graphical abstract Method proposal for ibuprofen quantification using digital image processing software (Fiji) | Thin-layer chromatography quantification of ibuprofen using digital imaging | 10.1007/s00764-023-00255-y |
2023-11-01 | In order to further understand the effects of the Reynolds number on the flow field within a low-pressure turbine with incoming wakes, the transition SST turbulence model was employed for numerical simulation under four Reynolds number conditions ranging from 0.6×10 5 to 3.0×10 5 . The numerical results showed that the boundary layer separation at the rear part of the suction surface was prone to occur in the condition of low Reynolds number (Re 2th = 0.6×10 5 ), and the separation bubble was semi-open and semi-closed. The separation bubble impedes the development of the passage vortex and wall vortex towards mid-span region. When the Reynolds number exceeds 1.0×10 5 , boundary layer separation does not occur. The influence of Reynolds number on the total pressure loss coefficient is primarily evident on the suction surface side, and the growth rate of total pressure loss coefficient first increases and then decreases along the streamwise direction. As the Reynolds number increases from 0.6×10 5 to 3.0×10 5 , the peak point location of total pressure loss decreases by approximately 12 %. The influence of Reynolds number on corner vortex and wall vortex is relatively more sensitive compared to that of passage vortex. | Effects of Reynolds number on the flow field in a low-pressure turbine with incoming wakes | 10.1007/s12206-023-1027-z |
2023-11-01 | The paper presents parameters of two multi-spectral X-ray detectors based on high resistivity chromiumcompensated gallium arsenide, which convert X-ray signal directly into electrical signal. Detectors consist of 80×80 and 256×256 pixels on 250 and 55 μm pitches, respectively. Their sensitive layer thickness ranges between 500 and 550 μm. At 3–4 keV photon energy, detectors offer high-quality X-ray images in the X-ray radiation range of 10 to 30 keV. Detectors allow distinguishing average densities between 0.3 and 2.4 g/cm 3 for 3D printed polymer composites. | Multi-Spectral X-Ray Detectors for Nondestructive Testing of 3D Printed Polymer Composites | 10.1007/s11182-023-03004-0 |
2023-11-01 | Purpose Flexible ureteroscopy (fURS) is steadily gaining popularity in the management of renal calculi, including those located in the lower pole (LP). Due to difficulty in accessing to the LP of kidney in minority of cases with fURS and reports of lower stone-free rate (SFR), it is still considered as a challenge in selected cases. The purpose of the review was to analyze the various aspects of fURS for LP stones. Methods An extensive review of the recent literature was done including different factors such as anatomy, preoperative stenting, stone size, flexible scopes, types of lasers, laser fibers, suction, relocation, stone-free rates, and complications. Results The significance of various lower pole anatomical measurements remain a subject of debate and requires standardization. Recent improvements in fURS such as single-use digital scopes with better vision and flexibility, high power laser, thulium fiber laser, smaller laser fiber, and accessories have significantly contributed to make flexible ureteroscopy more effective and safer in the management of LP stone. The utilization of thulium fiber lasers in conjunction with various suction devices is being recognized and can significantly improve SFR. Conclusions With the significant advancement of various aspects of fURS, this treatment modality has shown remarkable efficacy and gaining widespread acceptance in management of LP kidney stones. These developments have made the fURS of LP stones less challenging. | Flexible ureteroscopy for lower pole calculus: is it still a challenge? | 10.1007/s00345-023-04606-6 |
2023-11-01 | Abstract Nanoparticles of the lipid-transporting system of the organism, low-density lipoproteins (LDL) of blood plasma, are prone to free radical peroxidation with formation of their main modified forms – oxidized LDL itself (containing hydroperoxy-acyls in phospholipids of the outer layer of particles) and dicarbonyl-modified LDL (apoprotein B-100 in which chemically modified via the Maillard reaction). Based on the study of free radical oxidation kinetics of LDLs, it was found that the existing in the literature designation of “oxidized lipoproteins” is incorrect because it does not reveal the nature of oxidative modification of LDLs. It was shown in this study that the “atherogenic” LDLs (particles of which are actively captured by the cultured macrophages) are not the oxidized LDL (in which LOOH-derivatives of phospholipids are formed by enzymatic oxidation by C-15 lipoxygenase of rabbit reticulocytes), but dicarbonyl-modified LDLs. Important role of the dicarbonyl-modified LDLs in the molecular mechanisms of atherogenesis and endothelial dysfunction is discussed. | Differences in Structural Changes and Pathophysiological Effects of Low-Density Lipoprotein Particles upon Accumulation of Acylhydroperoxy Derivatives in Their Outer Phospholipid Monolayer or upon Modification of Apoprotein B-100 by Natural Dicarbonyls | 10.1134/S0006297923110196 |
2023-10-31 | Ductility is the ability of a material to deform without suffering brittle failure under stresses. Once the load ceases, the acquired deformation maintains over time. On the contrary, a stone is fragile when, subjected to a load, it deforms but, if the load continues, it suddenly breaks. The ductile or fragile facets are homogeneous and isotropic in the stones, but they can mainly vary according to the operating load and temperature. At low temperatures, particularly in polar and subpolar climates, limestone used as a building material and in stone heritage presents an increase in the yield stress. The fragile behavior at lower temperature is higher than at room temperature (20 °C). In this research, the mechanical performance of the Portuguese Blue limestone in dry and saturated conditions and different operating temperatures was accessed in three steps of −20 °C, 0 °C, and + 20 °C. A series of mechanical properties (e.g., uniaxial compressive and flexural strengths, point load strengths index, abrasion resistance, anchorage rupture load, impact resistance, hardness, and abrasion resistance) have been estimated. The results evidence a general progressive increase of the stone’s strengths at low temperature. This is due to a stone decrease in thermal energy and associated reduction in atomic or molecular motion. The reduced motion results in a decrease in internal friction, and it allows the solid to become more rigid, leading to increased mechanical strength. Studying the mechanical properties at various steps of temperatures supports the correct selection of stone materials proper for specific environmental conditions and intended application. | Exploring the Mechanical Properties of Stone Heritage: Investigating the Effects of Low Temperatures on Ductile — Brittle Transition | 10.1007/s12371-023-00892-z |
2023-10-31 | Background Cardiac fibrosis is one of the top killers among fibrotic diseases and continues to be a global unaddressed health problem. The lack of effective treatment combined with the considerable socioeconomic burden highlights the urgent need for innovative therapeutic options. Here, we evaluated the anti-fibrotic properties of extracellular vesicles (EVs) derived from human induced pluripotent stem cells (hiPSCs) that were cultured under various oxygen concentrations. Methods EVs were isolated from three hiPSC lines cultured under normoxia (21% O 2 ; EV-N) or reduced oxygen concentration (hypoxia): 3% O 2 (EV-H3) or 5% O 2 (EV-H5). The anti-fibrotic activity of EVs was tested in an in vitro model of cardiac fibrosis, followed by a detailed investigation of the underlying molecular mechanisms. Sequencing of EV miRNAs combined with bioinformatics analysis was conducted and a selected miRNA was validated using a miRNA mimic and inhibitor. Finally, EVs were tested in a mouse model of angiotensin II-induced cardiac fibrosis. Results We provide evidence that an oxygen concentration of 5% enhances the anti-fibrotic effects of hiPS-EVs. These EVs were more effective in reducing pro-fibrotic markers in activated human cardiac fibroblasts, when compared to EV-N or EV-H3. We show that EV-H5 act through the canonical TGFβ/SMAD pathway, primarily via miR-302b-3p, which is the most abundant miRNA in EV-H5. Our results show that EV-H5 not only target transcripts of several profibrotic genes, including SMAD2 and TGFBR2 , but also reduce the stiffness of activated fibroblasts. In a mouse model of heart fibrosis, EV-H5 outperformed EV-N in suppressing the inflammatory response in the host and by attenuating collagen deposition and reducing pro-fibrotic markers in cardiac tissue. Conclusions In this work, we provide evidence of superior anti-fibrotic properties of EV-H5 over EV-N or EV-H3. Our study uncovers that fine regulation of oxygen concentration in the cellular environment may enhance the anti-fibrotic effects of hiPS-EVs, which has great potential to be applied for heart regeneration. Graphical Abstract | Hypoxia enhances anti-fibrotic properties of extracellular vesicles derived from hiPSCs via the miR302b-3p/TGFβ/SMAD2 axis | 10.1186/s12916-023-03117-w |
2023-10-30 | TX-80 low-transformation-temperature (LTT) welding wire was used to replace the traditional ER 307Si welding wire to realize the connection of 22SiMn2TiB armor steel in manual overlay welding. The previously existing issues, such as welding cracks, large welding deformation, and severe welding residual stress, were solved to ensure good strength and ductility requirements. In particular, with the same welding conditions, TX-80 LTT wire eliminates welding cracks. It reduces the welding deformation no matter the base pretreatment of pre-setting angle or no pre-setting angle. By comparison, it was found that the microstructure at the TX-80 weld is mainly composed of martensite and a small amount of retained austenite. In contrast, the microstructure of the ER 307Si weld consists of a large amount of austenite and a small amount of skeleton-like ferrite. The variation trend of residual stress and microhardness from the weld to the base were investigated and compared with the mechanical properties of base materials. The TX-80 and the ER 307Si tensile samples elongation is 6.76% and 6.01%, while the ultimate tensile strengths are 877 and 667 MPa, respectively. The average impact toughness at room temperature of the ER 307Si weld is 143.9 J/cm 2 , much higher than that of the TX-80 weld, which is only 36.7 J/cm 2 . The relationship between impact and tensile properties with microstructure species and distribution was established. In addition, the fracture surface of the tensile and the impact samples was observed and analyzed. Deeper dimples, fewer pores, larger radiation zone, and shear lips of TX-80 samples indicate better tensile ductility and worse impact toughness than those of ER 307Si weld. | Mechanical performance of 22SiMn2TiB steel welded with low-transformation-temperature filler wire and stainless steel filler wire | 10.1007/s42243-023-01098-x |
2023-10-30 | Successful and efficient pest management is key to sustainable horticultural food production. While greenhouses already allow digital monitoring and control of their climate parameters, a lack of digital pest sensors hinders the advent of digital pest management systems. To close the control loop, digital systems need to be enabled to directly assess the state of different insect populations in a greenhouse. The presented article investigates the feasibility of acoustic sensors for insect detection in greenhouses. The study is based on an extensive dataset of acoustic insect recordings made with an array of high-quality microphones under noise-shielded conditions. By mixing these noise-free laboratory recordings with environmental sounds recorded with the same equipment in a greenhouse, different signal-to-noise ratios (SNR) are simulated. To explore the possibilities of this unique and novel dataset, two deep-learning models are trained on this simulation data. A simple spectrogram-based model represents the baseline for a comparison with a model capable of processing multi-channel raw audio data. Making use of the unique possibility of the dataset, the models are pre-trained on clean data and fine-tuned on noisy data. Under lab conditions, results show that both models can make use of not just insect flight sounds but also the much quieter sounds of insect movements. First attempts under simulated real-world conditions showed the challenging nature of this task and the potential of spatial filtering. The analysis enabled by the proposed methods for training and evaluation provided valuable insights that should be considered for future work. | Towards noise robust acoustic insect detection: from the lab to the greenhouse | 10.1007/s13218-023-00812-x |
2023-10-28 | Alluvial floodplains are a prominent part of rivers and play a vital role in flood mitigation and sediment detention. In the sediment-laden lower Yellow River (LYR), the floodplains have lost the sediment supply and are experiencing competition between land development and protection since the start of the operation of the Xiaolangdi Reservoir (XLD) in 2000. The objective of this paper is to investigate the sediment distribution and morphological changes of the floodplains in a typical wandering reach of the LYR based on the evolution in measured elevations of cross-sectional topography. The results show that the floodplains have gradually shifted from net sediment deposition to deficit. The cumulative eroded volume since the full operation of the XLD in 2002 has been approximately 5.74 × 10 8 m 3 . The erosion rate was approximately 3.25 cm/year, and the most eroded sediment originated from the right floodplain. The sediment erosion results in the adjustment of the cross-sectional topography with abrupt vertical changes in the floodplains. Through discussion, the sediment deficit and morphological changes have mainly been as a result of no floods due to the operation of the XLD and the human use of floodplain sediment. The water–sediment regulation scheme (WSRS) of the XLD has resulted in a fully scoured river channel to enhance the flood discharge capacity and has effectively controlled the flood peak to reduce the inundated risk of floodplains. The floodplain has, therefore, lost its sediment supply. In addition, the intensity of land development and construction in the floodplain has increased for the hardly inundated risks, causing a larger sediment requirement to form abrupt vertical changes in the floodplain topography with artificial land features. | Sediment deficit and morphological changes of alluvial floodplain in wandering reach of the lower Yellow River after Xiaolangdi Reservoir operation | 10.1007/s12665-023-11231-4 |
2023-10-27 | Carbon fiber-reinforced polymer (CFRP) composite joint structures based on interference fit exhibit superior mechanical properties compared to equivalent joint geometries utilizing clearance fits. The present research investigates the mechanical properties and failure mechanism of CFRP interference-fit joints subject to long-term exposure to low temperatures. A series of studies were designed to examine with interference-fit sizes ranging from 0 to 2.11%, subjected to temperatures between − 60 and 20 °C, and aging periods from 0 to 18 months. Tensile tests were conducted on these samples. Using a microscale analysis, three-dimensional representative volume elements (3D-RVEs) models were constructed to analyze the internal state, distribution of thermal residual stress, and damage initiation mechanism of CFRP subjected to low-temperature exposure. The results show that the strength and stiffness of the CFRP joints initially increase, reach a peak, and subsequently decrease with an increase in either the interference-fit size or aging time. The strength and stiffness of the considered geometries exhibit an approximately linear increase with decreasing temperature. Inside the CFRP, exposure to low temperatures causes the formation of thermal residual stress, which is particularly high in areas with closely spaced fibers. Short-term low temperature enhances the bonding force between the fiber and matrix, thereby improving the mechanical properties of the CFRP interference-fit joint structures. Following prolonged exposure to low temperatures, the debonding cracks formation increase in regions with concentrated residual stress, thereby decreasing the strength and stiffness of the structure. | Multi-stage mechanical behavior and damage mechanism of composite interference-fit joints subject to long-term low-temperature aging | 10.1007/s40430-023-04439-9 |
2023-10-27 | La/Pr co-doped ceria (LCP) is processed to fabricate low-temperature ceramic fuel cell based on industrial-grade rare-earth carbonate electrolyte that is reached above a maximum power density of 750 mW/cm 2 at 520 °C. The charge carriers are investigated through LCP fuel cell having symmetric NCAL (Ni 0.8 Co 0.15 Al 0.05 LiO 2-δ ) electrodes using proton conductor BCZY (BaCe 0.7 Zr 0.1 Y 0.2 O 3-δ ) as a blocking layer and are found protons that dominate during the cell operation. The results of associated characterizations for HCC (hydrogen concentration cell) and the OCC (oxygen concentration cell) reveal that LCP material is mixed conductor of both protons and oxygen ions simultaneously. Transmission electron microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis before and after the electrochemical testing of the cell are performed which show an amorphous layer of LiOH/Li 2 CO 3 mixture that is formed after the tests on the surface of LCP structure. Conceptually, it looks that LiOH/Li 2 CO 3 mixture in molten state in the interface region of two-phase material promotes the proton conduction through LCP electrolyte, with negligible oxygen ion conduction. | Proton Conduction and Electrochemical Performance of La/Pr co-Doped Ceria Electrolyte in Ceramic Fuel Cell | 10.1007/s40684-023-00532-5 |
2023-10-25 | In this study, the low temperature creep properties of multiphase bituminous materials (binder, mastic, Fine Aggregate Matrix—FAM, and mixture) were experimentally evaluated, and the impact of size effect on FAM and mixture specimen was also assessed. First, the mix design of mastic and FAM was performed based on the reference mixture Asphalt Concrete (AC) 22 TS. The mathematical adaptation to the boundary sieve method was applied to calculate FAM gradation and binder content. Next, a preparation method was proposed to produce Fine Aggregate Matrix (FAM) in a laboratory environment, and scale-up slab samples were also fabricated for FAM and mixture specimens to evaluate the size effect phenomenon. Finally, three-point bending (3 PB) creep tests were conducted on the multiphase bituminous specimens with different dimensions at -6 °C, -12 °C, and -18 °C with a modified Bending Beam Rheometer (BBR) device and a dynamic loading machine, depending on the sample size. Results indicate that the creep stiffness of the FAM was close to mixtures and much higher than the one observed in binder and mastic. The proposed fabrication approach provides a satisfactory method for preparing a representative FAM phase in the mixture, while the air voids can be easily adjusted during the slab compaction procedure. This study supports the idea of using FAM to discriminate asphalt mixtures for cold regions. The correlation between up-scaled FAM and mixture specimens should be further investigated, including different mixture types and corresponding FAM. | Fabrication and characterization of multiphase bituminous materials for cold region pavements | 10.1186/s43065-023-00088-3 |
2023-10-23 | In this paper, Al-Cu alloy-based Si 3 N 4 composite was prepared by using a powder metallurgy technology. The phase, surface appearance and hardness of the composites with different Si 3 N 4 contents were investigated. The water lubrication behaviors of Al-Cu alloy-based Si 3 N 4 composites were evaluated, and the corresponding low friction mechanisms were explained. Experimental results show that the main structure of sintered Al-Cu alloy contains of α (Al) + θ (CuAl 2 ) metal phase. With the addition of Si 3 N 4 , the AlN, Al 2 O 3 and SiAlON ceramic phases appear for the Al-Cu alloy-based Si 3 N 4 composites. The composites with 40 wt.% Si 3 N 4 content demonstrates flat net structure on the surface with the highest hardness. Under water lubrication condition, the low friction coefficient of 0.05 can only be achieved for the composites with proper Si 3 N 4 content. Analysis reveals that the flat contact surface and tribo-chemical reaction seem to be the two essential conditions for the low friction. The major wear mechanisms transfer from mechanically dominated wear at the running-in process to the tribo-chemical dominant at the low friction stage. | Preparation and Water Lubrication Behaviors of Al-Cu Alloy-Based Si3N4 Composites | 10.1007/s11665-023-08845-x |
2023-10-23 | Background Chronic hepatitis B virus (HBV) infection is a serious global health concern, with an increased incidence and risk of developing cirrhosis and hepatocellular carcinoma (HCC). Patients chronically infected with HBV are likely to experience chronic oxidative stress, leading to mitochondrial dysfunction. Photobiomodulation is induced by the absorption of low-level laser therapy (LLLT) with a red or infrared laser by cytochrome C oxidase enzyme, resulting in mitochondrial photoactivation. Although it is widely used in clinical practice, the use of LLL as adjuvant therapy for persistent HBV infection is uncommon. This study aimed to investigate the effect of LLLT dosage from 2 J/cm 2 to 10 J/cm 2 of red diode laser (650 nm) on both hepatoma cell lines (HepG2.2.15 [integrated HBV genome stable cell model] and non-integrated HepG2), with a subsequent impact on HBVsvp production. Methods The present study evaluated the effects of different fluences of low-level laser therapy (LLLT) irradiation on various aspects of hepatoma cell behavior, including morphology, viability, ultrastructure, and its impact on HBVsvp synthesis. Results In response to LLLT irradiation, we observed a considerable reduction in viability, proliferation, and HBVsvp production in both hepatoma cell lines HepG2.2.15 and HepG2. Ultrastructural modification of mitochondria and nuclear membranes: This effect was dose, cell type, and time-dependent. Conclusions The use of LLLT may be a promising therapy for HCC and HBV patients by reducing cell proliferation, HBVsvp production, and altering mitochondrial and nuclear structure involved in cellular death inducers. Further research is required to explore its clinical application. | Photobiological modulation of hepatoma cell lines and hepatitis B subviral particles secretion in response to 650 nm low level laser treatment | 10.1186/s43046-023-00190-3 |
2023-10-21 | Background Silicon nanoparticles (SiO 2 -NPs) play a crucial role in plants mitigating abiotic stress. However, the regulatory mechanism of SiO 2 -NPs in response to multiple stress remains unclear. The objectives of this study were to reveal the regulatory mechanism of SiO 2 -NPs on the growth and photosynthesis in cotton seedlings under salt and low-temperature dual stress. It will provide a theoretical basis for perfecting the mechanism of crop resistance and developing the technology of cotton seedling preservation and stable yield in arid and high salt areas. Results The results showed that the salt and low-temperature dual stress markedly decreased the plant height, leaf area, and aboveground biomass of cotton seedlings by 9.58%, 15.76%, and 39.80%, respectively. While SiO 2 -NPs alleviated the damage of the dual stress to cotton seedling growth. In addition to reduced intercellular CO 2 concentration, SiO 2 -NPs significantly improved the photosynthetic rate, stomatal conductance, and transpiration rate of cotton seedling leaves. Additionally, stomatal length, stomatal width, and stomatal density increased with the increase in SiO 2 -NPs concentration. Notably, SiO 2 -NPs not only enhanced chlorophyll a, chlorophyll b, and total chlorophyll content, but also slowed the decrease of maximum photochemical efficiency, actual photochemical efficiency, photochemical quenching of variable chlorophyll, and the increase in non-photochemical quenching. Moreover, SiO 2 -NPs enhanced the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase and phosphoenolpyruvate carboxylase, improved leaf water potential, and decreased abscisic acid and malondialdehyde content. All the parameters obtained the optimal effects at a SiO 2 -NPs concentration of 100 mg L − 1 , and significantly increased the plant height, leaf area, and aboveground biomass by 7.68%, 5.37%, and 43.00%, respectively. Furthermore, significant correlation relationships were observed between photosynthetic rate and stomatal conductance, stomatal length, stomatal width, stomatal density, chlorophyll content, maximum photochemical efficiency, actual photochemical efficiency, photochemical quenching of variable chlorophyll, and Rubisco activity. Conclusion The results suggested that the SiO 2 -NPs improved the growth and photosynthesis of cotton seedlings might mainly result from regulating the stomatal state, improving the light energy utilization efficiency and electron transport activity of PSII reaction center, and inducing the increase of Rubisco activity to enhance carbon assimilation under the salt and low-temperature dual stress. | Regulatory effects of silicon nanoparticles on the growth and photosynthesis of cotton seedlings under salt and low-temperature dual stress | 10.1186/s12870-023-04509-z |
2023-10-21 | Detecting low-abundance mutations is of particular interest in the fields of biology and medical science. However, most currently available molecular assays have limited sensitivity for the detection of low-abundance mutations. Here, we established a platform for detecting low-level DNA mutations with high sensitivity and accuracy by combining enhanced- ice -COLD-PCR (E- ice -COLD-PCR) and pyrosequencing with di-base addition (PDBA). The PDBA assay was performed by selectively adding one di-base (AG, CT, AC, GT, AT, or GC) instead of one base (A, T, C, or G) into the reaction at a time during sequencing primer extension and thus enabling to increase the sequencing intensity. A specific E- ice -COLD-PCR/PDBA assay was developed for the detection of the most frequent BRAF V600E mutation to verify the feasibility of our method. E- ice -COLD-PCR/PDBA assay permitted the reliable detection of down to 0.007% of mutant alleles in a wild-type background. Furthermore, it required only a small amount of starting material (20 pg) to sensitively detect and identify low-abundance mutations, thus increasing the screening capabilities in limited DNA material. The E- ice -COLD-PCR/PDBA assay was applied in the current study to clinical formalin-fixed paraffin-embedded (FFPE) and plasma samples, and it enabled the detection of BRAF V600E mutations in samples that appeared as a wild type using PCR/conventional pyrosequencing (CP) and E- ice -COLD-PCR/CP. E- ice -COLD-PCR/PDBA assay is a rapid, cost-effective, and highly sensitive method that could improve the detection of low-abundance mutations in routine clinical use. | Combining E-ice-COLD-PCR and Pyrosequencing with Di-Base Addition (PDBA) Enables Sensitive Detection of Low-Abundance Mutations | 10.1007/s12010-023-04718-0 |
2023-10-20 | This paper has clarified the optical fiber links in the presence of proposed device structures for ultrahigh thermal stability and ultralow thermal sensitivity. The study is clarified to design a thermal planar arrayed waveguide grating (AWG)-based SiO 2 , LiNbO 3 and Ga (1− x ) Al ( x ) As core material. Plastic cladding material is based on polyhexafluoro isopropyl 2-fluoroacrylate dibutyl phathalate (PHFIP 2-FA-DBP). Plastic polyhexafluoro isopropyl 2-fluoroacrylate (PHFIP 2-FA) material is used as under-cladding material. These hybrid materials are integrated on a silicon (Si) substrate. The performance parameters of this device have been investigated in the range of the simulation parameters. We have investigated a thermal AWG devices design signature for ultrahigh thermal stability and ultralow thermal sensitivity. The refractive index dependence of the various plastic materials used as over-/under-cladding is clarified versus wavelength variations. | Optical fiber links based A thermal planar AWG for ultrahigh thermal stability and ultralow thermal sensitivity | 10.1007/s12596-023-01456-8 |
2023-10-20 | To enhance the product quality, manufacturers of dried fruits are dedicated to developing reliable methods for assessing ripeness. In this study, a densimetric flotation method was employed to categorize mulberries into five distinct ripening stages (D1–D5, 0.905–1.055 g/cm³). The influence of ripening on mulberry water status, distribution, microstructure, drying characteristics, and product quality was examined. Heat pump drying, utilizing a temperature of 60 °C, relative humidity of 15%, and air velocity of 2 m/s, was employed as the drying technique for mulberries. As ripening progressed, the water binding capability initially decreased and then increased. Simultaneously, water distribution and cell microstructure shifted, resulting in an initial reduction followed by an extension in drying time. The drying time initially decreased and then increased with increasing maturity, with D4 fruits displaying the shortest drying time (13.9 h). This was 35.05%, 24.04%, 20.14%, and 6.47% shorter than the drying times observed in stages D1, D2, D3, and D5, respectively. Ripeness significantly affected the volatile composition, color, texture, and sensory attributes of dried fruits. D1 fruits were not suitable for drying due to their intact cellular structure, lengthy drying time, and poor sensory quality of the resulting product. Conversely, D4 and D5 fruits exhibited shorter drying times and their products possessed a robust fruity aroma, improved palatability, and overall acceptance. This rendered them ideal candidates for the drying process. The findings of this research have practical implications for effective identification and drying procedures during mulberry ripening. | Grading by Fruit Density: An Effective way to Control the Drying Characteristics and Qualities of Mulberry (Morus nigra L.) | 10.1007/s11947-023-03230-x |
2023-10-20 | In DESTINY-Breast04 (DB-04), safety and efficacy of HER2-targeted antibody-drug conjugate (ADC) trastuzumab deruxtecan (T-DXd) in previously treated HER2-low unresectable/metastatic breast cancer were established. This manuscript describes the analytical validation of PATHWAY Anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody (PATHWAY HER2 (4B5)) to assess HER2-low status and its clinical performance in DB-04. Preanalytical processing and tissue staining parameters were evaluated to determine their impact on HER2 scoring. The recommended antibody staining procedure provided the optimal tumor staining, and deviations in cell conditioning and/or antibody incubation times resulted in unacceptable negative control staining and/or HER2-low status changes. Comparisons between antibody lots, kit lots, instruments, and day-to-day runs showed overall percent agreements (OPAs) exceeding 97.9%. Inter-laboratory reproducibility showed OPAs of ≥97.4% for all study endpoints. PATHWAY HER2 (4B5) was utilized in DB-04 for patient selection using 1340 tumor samples (59.0% metastatic, 40.7% primary, (0.3% missing data); 74.3% biopsy, 25.7% resection/excisions). Overall, 77.6% (823/1060) of samples were HER2-low by both central and local testing, with the level of concordance differing by sample region of origin and collection date. In DB-04, the efficacy of T-DXd over chemotherapy of physician’s choice was consistent, regardless of the characteristics of the sample used (primary or metastatic, archival, or newly collected, biopsy or excision/resection). These results demonstrate that PATHWAY HER2 (4B5) is precise and reproducible for scoring HER2-low status and can be used with multiple breast cancer sample types for reliably identifying patients whose tumors have HER2-low expression and are likely to derive clinical benefit from T-DXd. | Analytical and clinical validation of PATHWAY Anti-HER-2/neu (4B5) antibody to assess HER2-low status for trastuzumab deruxtecan treatment in breast cancer | 10.1007/s00428-023-03671-x |
2023-10-20 | Background Energy homeostasis is essential for the adaptation of animals to their environment and some wild animals keep low metabolism adaptive to their low-nutrient dietary supply. Giant panda is such a typical low-metabolic mammal exhibiting species specialization of extremely low daily energy expenditure. It has low levels of basal metabolic rate, thyroid hormone, and physical activities, whereas the cellular bases of its low metabolic adaptation remain rarely explored. Results In this study, we generate a single-nucleus transcriptome atlas of 21 organs/tissues from a female giant panda. We focused on the central metabolic organ (liver) and dissected cellular metabolic status by cross-species comparison. Adaptive expression mode (i.e., AMPK related) was prominently displayed in the hepatocyte of giant panda. In the highest energy-consuming organ, the heart, we found a possibly optimized utilization of fatty acid. Detailed cell subtype annotation of endothelial cells showed the uterine-specific deficiency of blood vascular subclasses, indicating a potential adaptation for a low reproductive energy expenditure. Conclusions Our findings shed light on the possible cellular basis and transcriptomic regulatory clues for the low metabolism in giant pandas and helped to understand physiological adaptation response to nutrient stress. | Single-nucleus transcriptome inventory of giant panda reveals cellular basis for fitness optimization under low metabolism | 10.1186/s12915-023-01691-2 |
2023-10-19 | The world is currently in the midst of an energy transition, in which renewable and low-carbon energy is replacing the use of fossil fuels. Along the way, however, planning for and adapting to impacts of climate change is urgently needed, as these are projected to intensify in the future, despite ambitious mitigation efforts. Since the low-carbon energy transition is likely to involve many international interdependencies and connections between countries and regions, assessments of cross-border impacts of climate change, i.e., consequences of climate change that occur remotely from the location of their initial impact, are of utmost importance to ensure the decarbonisation of society is safe and sustainable. This paper utilises expert interviews and a general morphological analysis with the shared socioeconomic pathways to situate national decarbonisation efforts within a global context and identify cross-border impacts of climate change that may affect the energy transition, using the Finnish energy sector as a case study. Interestingly, many of the global development trends that were found to have a boosting effect on the Finnish energy transition, also increased the risk from cross-border climate change impacts, stressing the importance of rigorous adaptation planning. The findings affirm the need for studying national energy transitions from a global perspective and highlight the tendency of climate change impacts to be transmitted across borders via complex pathways. The study offers valuable insights into the importance of cross-border impacts for adaptation planning pertinent to any country or region currently engaged, or planning to engage, in the global low-carbon transition. | Cross-border impacts of climate change affect the energy transition: Insights from the Finnish energy sector | 10.1007/s10584-023-03619-9 |
2023-10-17 | The extent and occurrence of extremely low-flow events are necessary to determine the minimum river flow. Since the true probability distribution is usually not known, the best fitting distribution function describing the low flow in the catchment is important for reliable estimation of low flow and its frequency. The Temsa River is one of the most important tributaries of the Abay River Basin in Ethiopia and has a high ecological value for the country that can be affected by land cover changes. Climate influences watershed development, while landscape features control the accumulation and release of water over time, influencing stream flow, such as low flow. Therefore, analyzing the state of river discharge is important for the economic management of water resources. Rapid population growth has raised serious concerns about the adequacy of the Temsa River’s future water intake in terms of quantity and quality. However, future water resources planning requires information on water flow variability and trends. The aim of this study is to identify and analyze the existing Temsa watersheds and their current status based on river water data collected by the Ethiopian Ministry of Water and Energy from 1997 to 2021 GC. Analysis focused on daily flow, mean annual flow, mean monthly flow, and consecutive 7-day mean minimum flow were included in the model. Methods for trend detection and quantification were the Mann–Kendall test (MK) and Sen’s slope estimator (SS). The results of the MK and SS tests indicate the existence of a trend of statistical significance. The study shows a positive trend for two models and a negative trend for the other two models. The daily discharge analysis and the annual average flow analysis show a decreasing trend and the second model shows an increasing trend. BFI results show that the proportion of groundwater in the watershed is moderate, 73.6%, and the lognormal distribution fits the frequency analysis data. | Quantitative analysis and modeling of minimum flow patterns in Temsa River, Abbay Basin, Ethiopia | 10.1186/s44147-023-00297-3 |
2023-10-16 | As the key material of aero-engine turbine blades, nickel-based single-crystal superalloys are in long-term service under high temperature, high pressure, and high rotational speed and are prone to fatigue failure. DD6 superalloy is a nickel-based single-crystal superalloy widely used in advanced aero-engines in China. In this work, the recrystallization study of laser shock peened nickel-based single-crystal superalloy was carried out; the finite element model of laser shock peened nickel-based single-crystal superalloy was established, and the influence law of laser shock peening overlap rate and laser shock peening times on the residual stress field was obtained. Secondly, the effects of different laser shock peening temperatures on the material properties of the nickel-based single-crystal superalloy after heat treatment were investigated. It was concluded that heating up to 300 °C during laser shock peening of the nickel-based single-crystal superalloy can effectively suppress the recrystallization. | Research on Finite Element Simulation and Recrystallization of Laser Shock Peened Nickel-Based Single-Crystal Superalloy | 10.1007/s11665-023-08823-3 |
2023-10-16 | Utilizing wood in space-based applications poses challenges because the lack of electrical conductivity of this material can lead to local charging while off-gassing under high vacuum can potentially also have adverse effects. However, carbonized wood exhibits electrical conductivity and does not produce gases in a vacuum, making it a potential candidate for use in spacecraft. Even so, erosion by atomic oxygen (AO) at low altitude orbits could potentially degrade wood surfaces. The present study therefore investigated the effects of AO irradiation on carbonized and uncarbonized milled wood lignin (MWL) obtained from both softwood and hardwood sources. The lignin source was found to significantly affect resistance to AO. Specifically, softwood-derived MWL underwent structural changes upon AO exposure whereas hardwood-derived MWL showed greater resistance due to the higher concentration of oxygen-containing functional groups in the latter. AO irradiation evidently induced changes in the carbon framework while affecting the micropore sizes and peak distribution ranges. These findings highlight the importance of selecting specific wood types and carbonization conditions when producing lignin-derived carbon materials for AO-exposed environments. Softwood MWL is evidently more vulnerable to AO erosion as a result of the guaiacyl structures in this material whereas hardwood MWL resists AO based on its oxygen-rich syringyl groups. The present work underscores the complex relationships between the wood type, concentration of oxygenated functional groups, and AO resistance. This research also suggests potential applications for wood-derived lignin carbon in low Earth orbit vehicles and highlights the need for additional studies as a means of better understanding the underlying mechanisms. | Microstructural changes in carbonized wood-lignin, a potential space material, in response to atomic oxygen irradiation | 10.1007/s13399-023-04957-5 |
2023-10-16 | Climate change and irresponsible urbanization practices are anticipated to further exacerbate flood risk. The different soil types’ physical, chemical, and biological characteristics significantly impact surface water movement, porosity, permeability, and infiltration potential. Therefore, soil infiltration is perhaps the most challenging and crucial process to characterize on a field scale. Various methods have been developed to measure the infiltration rate empirically and theoretically. However, the relationship between different soil types and infiltration rates in Sarawak remains unknown as no previous study has been conducted. This study uses the Storm Water Management Model (SWMM) to evaluate the infiltration rates for five different soil types: clay, clay loam, loam, sandy loam, and sand. 30 samples of various types and soil depths were examined at intervals of 0.5 m, 1.0 m, 1.5 m, 2.0 m, 2.5 m, and 3 m. The study was carried out using a standardized slope of 0.7% and an impervious land of 25% with a catchment size of 2 acres. Extreme rainfall data on the 5th and 6th of December 2021 was input into the infiltration model. Results showed that the difference between initial and final water storage of all the investigated soil depths for clay, clay loam, loam, sandy loam, and sand was found to be 48.42 mm, 51.20 mm, 58.01 mm, 66.96 mm, and 115.54 mm, respectively. The findings demonstrated that clay has the lowest water storage capability, followed by clay loam, loam, and sandy loam. Sand could store a comparatively large amount of rainwater. In contrast, sand has the highest infiltration rate with 2.541 mm/h, followed by sandy loam with 1.835 mm/h, loam with 1.432 mm/h, clay loam with 1.039 mm/h. Clay has the lowest infiltration rate, with 0.852 mm/h. This research concluded that sandy soil could significantly reduce surface runoff and help reduce flood risk in urban regions. | Evaluation of total infiltration and storage capacities for different soil types in Sarawak using SWMM | 10.1007/s43832-023-00042-0 |
2023-10-13 | The process of machine learning is introduced in detail. Recent developments in machine learning for low-dimensional electrocatalysts are briefly reviewed. Future directions and perspectives for machine learning in hydrogen evolution reaction are critically discussed. Efficient electrocatalysts are crucial for hydrogen generation from electrolyzing water. Nevertheless, the conventional "trial and error" method for producing advanced electrocatalysts is not only cost-ineffective but also time-consuming and labor-intensive. Fortunately, the advancement of machine learning brings new opportunities for electrocatalysts discovery and design. By analyzing experimental and theoretical data, machine learning can effectively predict their hydrogen evolution reaction (HER) performance. This review summarizes recent developments in machine learning for low-dimensional electrocatalysts, including zero-dimension nanoparticles and nanoclusters, one-dimensional nanotubes and nanowires, two-dimensional nanosheets, as well as other electrocatalysts. In particular, the effects of descriptors and algorithms on screening low-dimensional electrocatalysts and investigating their HER performance are highlighted. Finally, the future directions and perspectives for machine learning in electrocatalysis are discussed, emphasizing the potential for machine learning to accelerate electrocatalyst discovery, optimize their performance, and provide new insights into electrocatalytic mechanisms. Overall, this work offers an in-depth understanding of the current state of machine learning in electrocatalysis and its potential for future research. | Machine Learning-Assisted Low-Dimensional Electrocatalysts Design for Hydrogen Evolution Reaction | 10.1007/s40820-023-01192-5 |
2023-10-13 | Precision and traceable measurement of small forces have become increasingly important due to the rapid change in technology and miniaturization of devices. In this paper, we have discussed the design, development and metrological aspects of double bending beam force transducer for low-force measurements. To achieve this task, elastic spring element is designed and machined for fabricating the force transducer and virtually tested through the finite element analysis (FEA) method to validate its load capacity and to understand its mechanical behaviour. The metrological capability of spring element is determined with the application of small forces, sensing the applied forces through contact and non-contact methods. In the contact method, strain gauges are employed for the detection of induced strain on the spring element . For this, the maximum and minimum strain values and their distribution are found to get the optimum normalized output in the electrical unit of mV/V. In the non-contact method, a pair of light-emitting diode (LED) and light-dependent resistor (LDR) is utilized for the detection of the bending caused by the applied force. The optimal detectable deflection is found in the spring element through FEA. The experimental characterization results of the force transducers showed that the developed force transducers have good metrological capability in terms of high linearity and repeatability in the range of 0.3–3 N. | Development and Performance Evaluation of Double Bending Beam Force Transducer for Low-Force Measurement | 10.1007/s12647-023-00687-1 |
2023-10-13 | This paper investigates the problem of simultaneously predicting multiple binary responses by utilizing a shared set of covariates. Our approach incorporates machine learning techniques for binary classification, without making assumptions about the underlying observations. Instead, our focus lies on a group of predictors, aiming to identify the one that minimizes prediction error. Unlike previous studies that primarily address estimation error, we directly analyze the prediction error of our method using PAC-Bayesian bounds techniques. In this paper, we introduce a pseudo-Bayesian approach capable of handling incomplete response data. Our strategy is efficiently implemented using the Langevin Monte Carlo method. Through simulation studies and a practical application using real data, we demonstrate the effectiveness of our proposed method, producing comparable or sometimes superior results compared to the current state-of-the-art method. | A reduced-rank approach to predicting multiple binary responses through machine learning | 10.1007/s11222-023-10314-3 |
2023-10-13 | Achilles tendinopathy (AT) is a common debilitating tendon disorder in the lower extremity. Clinical presentation of AT might differ from place to place, depending on different variables including cultural factors. This study was conducted to determine the clinical picture of AT in a group of clients referring to an outpatient orthopedics clinic in Shiraz, southern Iran. In this cross-sectional study, a convenient sample of 61 (46 female and 15 male) patients attending to a referral outpatient clinic affiliated to Shiraz University of Medical Sciences with a definite diagnosis of AT was studied. Patients with partial- or full-thickness tear of Achilles tendon, history of radicular pain or lower extremity injury, previous history of surgery on their lower extremity, and pregnant women were excluded from the study. We used Maffulli et al. (Foot Ankle Surg 26:240–9, 2020) criteria for the diagnosis of AT in our patients. The patients had a mean age of 47.7 (SD 11.1) years and mean BMI of 28.7 (4.2) kg/m 2 . There was no significant correlation between the age and body mass index of the participants (Pearson’s r = –0.028, p = 0.832). The prevalence of insertional AT among 58 patients with only one site affected, was 84% (95% CI 72–92%), significantly ( p < 0.001) higher than that of midportional AT (16%). Women were more frequently affected than men ( p < 0.001). The clinical presentation of AT in southern Iran is somewhat different from those reported in other parts of the world. Further studies on larger groups of patients should be done to determine the causes of the observed differences. | Different clinical presentations of Achilles tendinopathy: a cross-sectional study | 10.1007/s00296-023-05485-1 |
2023-10-11 | Abstract Efficient isolation and sensitive quantification of Pseudomonas aeruginosa ( P. aeruginosa ) are crucial for identifying intrauterine infections and preventing the occurrence of intrauterine adhesion (IUA). However, traditional approaches, such as culture-based approach, are time-consuming. Herein, we constructed a detection scaffold by using primer exchange reaction (PER) that integrated the low-speed centrifugation–based isolation and sensitive quantification of target pathogenic bacteria. The established approach possesses several advantages, including (i) the approach is capable of simultaneous isolation and sensitive quantification of target bacteria; (ii) low-speed centrifugation or even manual equipment could be used to isolate target bacteria; and (iii) a low limit of detection was obtained as 54 cfu/mL. Based on this, the approach is a promising approach in analyzing P. aeruginosa from uterine secretions with IUA. Graphical Abstract | Primer Exchange Reaction (PER)–Based Construction of Scaffold for Low-Speed Centrifugation–Based Isolation and Quantitative Analysis of P. aeruginosa and its application in analyzing uterine secretions with intrauterine adhesion | 10.1007/s12010-023-04742-0 |
2023-10-11 | The incorporation of net-zero technology into preexisting energy networks is crucial for facilitating the shift toward an ecologically conscious and sustainable energy infrastructure. The primary objective of this integration is to effectively decrease carbon footprints and to provide a comprehensive understanding of the current approaches and trends related to the design and management frameworks of integrated energy networks. The initial section of this study establishes the foundation for a comprehensive examination of the particular challenges associated with decarbonization in the strategic and operational aspects of integrated energy networks. The subsequent analysis proceeds to elucidate the fundamental framework and technological architecture upon which these energy networks are constructed. This provides significant insights into the operational complexity and efficacy of the system. In addition, the paper provides a concise examination of prominent frameworks and alternative approaches that tackle the issue of low-carbon design and administration. The degree of accuracy facilitates individuals when selecting systems that align with the specific requirements of unique circumstances. Furthermore, this study provides explicit suggestions for future research based on an examination of the distinct attributes and framework of integrated energy networks. The anticipated outcome of implementing these recommendations is to enable the advancement of sustainable development and expedite the shift toward energy infrastructure with reduced carbon emissions. This will make a significant contribution to the collaborative endeavor of mitigating climate change and fostering a sustainable energy future. This study further elucidates the significant contribution of integrated energy networks in addressing climate change and enhancing energy efficiency. It achieves this by synthesizing a complete range of concepts sourced from many academic papers, industry reports, and case studies. This statement offers an examination of the multifaceted technological, legislative, and planning factors that contribute to the attainment of net-zero objectives. | Emerging Trends and Approaches for Designing Net-Zero Low-Carbon Integrated Energy Networks: A Review of Current Practices | 10.1007/s13369-023-08336-0 |
2023-10-10 | Background Near-infrared irradiation photobiomodulation (NIR-PBM) has been successfully used in periodontal treatment as an adjuvant tool to locally improve cell function and regeneration. Although the relationship between periodontitis and systemic disease constitutes an important aspect of periodontal clinical research, the systemic effects of NIR-PBM in periodontitis are not well known. In this study, we aimed to investigate the effects of NIR-PBM on systemic oxidative stress and inflammation in an apolipoprotein E (ApoE) knockout mouse model of periodontal disease (PD). Methods We evaluated alveolar bone loss by measuring the distance from the cementoenamel junction (CEJ) to the alveolar bone crest (ABC), reactive oxygen species (ROS) production in blood cells, inflammatory activity, plasma cholesterol levels, and lipid peroxidation levels in three experimental groups: (1) ApoEC, control group without intervention; (2) ApoEP, first molar ligation-induced periodontitis for 4 weeks; and (3) ApoEP + PBM, exposed to 808 nm continuous wave, ø ~ 3 mm2, 100 mW, 60 s of NIR-PBM for 7 consecutive days after 4 weeks of periodontitis. At the end of the experimental protocols, ApoEP mice presented significantly increased alveolar bone loss, ROS production, inflammatory activity, plasma cholesterol, and lipid peroxidation levels compared to the ApoEC group ( P < 0.05). NIR-PBM for 7 days in the ApoEP + PBM mice significantly decreased systemic ROS production, inflammatory response, plasma cholesterol, and lipid peroxidation levels, similar to those found in the ApoEC group ( P > 0.05). However, it was not capable of preventing alveolar bone loss ( P > 0.05 compared to ApoEP mice). Conclusion A 7-day treatment with NIR-PBM effectively reduces systemic oxidative stress and inflammatory parameters in hypercholesterolemic mice with PD. However, more studies with longer evaluation times are needed to confirm the systemic effects of locally applied NIR-PBM on PD associated with hypercholesterolemia. | Infrared laser therapy decreases systemic oxidative stress and inflammation in hypercholesterolemic mice with periodontitis | 10.1186/s12944-023-01934-9 |
2023-10-09 | Fine-grained low-alloy steels are prepared via hot rolling, warm rolling, and subsequent annealing in the intercritical zone, resulting in a microstructure consisting of a ferritic matrix and spherical cementite. Characterization of microstructure and mechanical properties indicated that when the average grain sizes decreased from 4.5 to 1.5 μm, a continuous improvement in yield strength and tensile strength was observed. Grain-refinement and precipitation strengthening of cementite are the key reasons for the significant increase in strength. Using crystal plasticity finite element methods, quasi-static tensile simulations were performed on steels with various grain sizes, and a set of crystal plasticity parameters suitable for fine-grained low-alloy steels was obtained. The simulation of size effects was innovatively performed by modifying the single-crystal strength based on the Hall–Petch relationship, and the simulations were in good agreement with the tested results. This provides a new, cost-effective, time-efficient, and highly reliable method for exploring the relationship between the mechanical properties and microstructure of fine-grained steel with complex microstructures. | Mechanical Properties of Fine-Grained Low Alloy Steel Investigated by Crystal Plasticity Finite Element Method | 10.1007/s11665-023-08791-8 |
2023-10-09 | Continuous-wave green vertical-cavity surface-emitting lasers based on self-formed quantum dots were realized with the lowest threshold current density of 51.97 A cm −2 . A short cavity (~4.0 λ, where λ is the wavelength in the media) was adopted to enhance the interaction between spontaneous emission and lasing mode, with a big coupling factor up to 0.094. AlN current confinement layer and the electroplated supporting copper plate were utilized to improve heat dissipation, with a low thermal resistance of 842 K W −1 . Room temperature low threshold lasing of green GaN-based vertical cavity surface emitting laser (VCSEL) was demonstrated under continuous wave (CW) operation. By using self-formed InGaN quantum dots (QDs) as the active region, the VCSEL emitting at 524.0 nm has a threshold current density of 51.97 A cm −2 , the lowest ever reported. The QD epitaxial wafer featured with a high IQE of 69.94% and the δ-function-like density of states plays an important role in achieving low threshold current. Besides, a short cavity of the device (~ 4.0 λ) is vital to enhance the spontaneous emission coupling factor to 0.094, increase the gain coefficient factor, and decrease the optical loss. To improve heat dissipation, AlN layer was used as the current confinement layer and electroplated copper plate was used to replace metal bonding. The results provide important guidance to achieving high performance GaN-based VCSELs. | Green Vertical-Cavity Surface-Emitting Lasers Based on InGaN Quantum Dots and Short Cavity | 10.1007/s40820-023-01189-0 |
2023-10-09 | Microstructure evolution on the surface of Fe-20Mn-6Al-0.6C-0.15Si austenitic low-density steel was studied by comparing with the microstructure at the core. In the present study, the austenite grain growth was in situ observed using laser scanning confocal microscope (LSCM). The microstructure of specimens on surface and at core was analyzed after LSCM experiments. The distribution of Mn and Al along axial direction was analyzed. The results show that the volatilization of Mn on the specimen surface during isothermal holding at high temperatures varying from 900 to 1200 °C results in a low stability of the austenite on the specimen surface, leading to the transformation of less stable austenite to ferrite during subsequent cooling process. The ferrite fraction on the specimen surface increases with isothermal temperature, indicating more Mn volatilization at higher temperature. In addition, because Mn volatilizes during isothermal holding at high temperatures, the austenite grain growth on the surface is different from that at the core. | Microstructure Evolution on the Surface of Fe-20Mn-6Al-0.6C-0.15Si Austenitic Low-Density Steel during Heat Treatment | 10.1007/s11665-023-08803-7 |
2023-10-08 | In the high-shear and low-pressure grinding process, the loose and small abrasive particles will agglomerate together to produce hydro-cluster effect, which drives the abrasive particles to remove the workpiece material. The liquid-body-armor-like grinding wheel parameters, especially, the abrasive fluid properties, have a direct influence on the hydro-cluster effect, which further determined the material removal efficiency and surface quality. Therefore, the experimental investigation was conducted to explore the effects of the abrasive type, size, and percentage on surface roughness Ra and material removal rate. To further explain the surface formation mechanism of the Inconel718 alloy workpiece, the autocorrelation function and the power spectral density function (PSD) of surface profiles was discussed. After the optimization of wheel parameters, the surface roughness Ra of Inconel718 alloy decreased from 0.3 to 0.094 μm. A material removal rate of 1.069 × 10 5 μm 3 /mm·s was obtained as well. The PSD curve mainly concentrated in 0–40 k Hz, indicating that a bigger cluster elastomer of abrasive particles was generated in the grinding zone. Additionally, the variation of workpiece surface morphology has validated the grinding performance. The original pretreatment scratches were completely removed. A smooth surface was obtained after grinding. The experiment results verified that the optimized grinding wheel was effective for HSLP grinding of Inconel718 alloy. | Effects of body-armor-like grinding wheel parameters on surface quality and material removal rate in high-shear and low-pressure grinding process | 10.1007/s40430-023-04492-4 |
2023-10-07 | Compared to conventional chemical/physical approaches, non-thermal plasma-based nanotechnology route has been emerging as an extremely promising alternative to fabricate nano-frameworks for electrochemical energy storage and conversion (EESC) devices owing to plasma being able to provide highly reactive non-equilibrium environment under mild conditions. Due to its energy-effectiveness, environmental-friendliness and scalability, plasma nano-technology-based strategies are currently serving as effective tools for different industrial and research applications and it is just a matter of time that they will become indispensable tools of electrode material synthesis and processing for EESC devices. Here, the details of progress on the nonthermal plasma technique are provided towards the nanostructured electrode fabrication for EESC devices based on plasma deposition, modification and etching. Critical plasma feedstocks like carbon, nitrogen, oxygen, and argon are discussed for maximizing the overall performance of EESC-based electrodes. The challenges of plasma strategy in such area is further analyzed. This review provides a detailed understanding and appreciation of low-temperature plasma application in EESC devices. | Plasma nanotechnology: novel tool for high-performance electrode materials for energy storage and conversion | 10.1007/s41614-023-00131-6 |
2023-10-06 | Background The most favorable anesthesia protocol during on-pump coronary artery bypass grafting (CABG) in patients with coronary heart disease remains unclear, despite previous publications regarding the interaction between anesthesia protocol and postoperative complications. The aim of the study was to compare the effect of a multimodal low-opioid anesthesia protocol (MLOP) on early postoperative complications during on-pump CABG. Methods A single-center prospective cohort study including 120 patients undergoing on-pump CABG aged 18 to 65 years, divided into two groups according to undergoing MLOP or routine-opioid anesthesia protocol (ROP). The analyzed parameters were plasma IL-6 levels, complications, duration of mechanical ventilation, length of intensive care unit stay, and hospitalization. Results In the MLOP group, the levels of IL-6 at the end of the surgery were 25.6% significantly lower compared to the ROP group (33.4 ± 9.4 vs. 44.9 ± 15.9, p < 0.0001), the duration of mechanical ventilation was significantly shorter (2.0 (2.0; 3.0) h vs. 4.0 (3.0; 5.0) h, p < 0.001), the incidence of low cardiac output syndrome was almost two and half times lower (7 (11.7%) vs. 16 (26.7%), p = 0.037), and also the incidence of postoperative atrial fibrillation was significantly lower (9 (15.0%) vs. 19 (31.7%), p = 0.031). Conclusion Our study confirms that using MLOP was characterized by significantly lower levels of IL-6 at the end of surgery and a lower incidence of low cardiac output syndrome and postoperative atrial fibrillation than ROP. Trial registration The study is registered in clinicaltrials.gov №NCT05514652. | Effects of multimodal low-opioid anesthesia protocol during on-pump coronary artery bypass grafting: a prospective cohort study | 10.1186/s13019-023-02395-y |
2023-10-06 | Background Plastic's remarkable durability presents a significant challenge for our planet, leading to widespread environmental damage. However, some organisms, such as Galleria mellonella larvae, have shown a unique capability to consume and degrade plastic, offering potential solutions to plastic pollution. In this study, we investigated the response of G. mellonella larvae to different diets, including artificial diet (AD), polyethylene low density mixed with AD (PELD + AD), and PELD alone. Using various microscopy techniques, we examined the larvae's hemocyte hemogram and mid-gut characteristics to understand their immune response and digestive system when exposed to plastic. Results The results revealed that PELD-only feeding negatively impacted hemocyte immunity, resulting in a significant decrease in total hemocyte counts compared to AD and AD + PELD feeding. Moreover, plastic consumption induced differential hemocyte alterations, affecting specific cell types. The presence of phagosomes in larval hemocytes and mid-gut cells during PELD-only feeding suggested active involvement in plastic breakdown. Conclusions These findings highlight the potential of G. mellonella larvae as a model organism to study responses to pollutants, emphasizing the urgent need to address plastic pollution's global threat. Further investigation is warranted to explore larval deformities, weight loss, and appetite changes, potentially influencing mortality rates and enzyme biochemistry. Understanding the impacts of plastic ingestion on G. mellonella larvae is crucial to develop effective strategies for mitigating plastic pollution's ecological implications. | Evaluation of Galleria mellonella immune response as a key step toward plastic degradation | 10.1186/s41936-023-00349-3 |
2023-10-05 | Background Low birth weight (LBW) is associated with short and long-term consequences including neonatal mortality and disability. Effective linkages in the continuum of care (CoC) for newborns at the health facility, community (primary care) and home care levels have a high tendency of minimizing adverse events associated with LBW. But it is unclear how these linkages work and what factors influence the CoC process in Ghana as literature is scarce on the views of health professionals and families of LBW infants regarding the CoC. Therefore, this study elicited the drivers influencing the CoC for LBW infants in Ghana and how linkages in the CoC could be strengthened to optimize quality of care. Methods A constructivist grounded theory study design was used. Data was collected between September 2020 to February 2021. A total of 25 interviews were conducted with 11 family members of LBW infants born in a secondary referral hospital in Ghana, 9 healthcare professionals and 7 healthcare managers. Audio recordings were transcribed verbatim, analyzed using initial and focused coding. Constant comparative techniques, theoretical memos, and diagramming were employed until theoretical saturation was determined. Results Emerging from the analysis was a theoretical model describing ten major themes along the care continuum for LBW infants, broadly categorized into health systems and family-systems drivers. In this paper, we focused on the former. Discharge, review, and referral systems were neither well-structured nor properly coordinated. Efficient dissemination and implementation of guidelines and supportive supervision contributed to higher staff motivation while insufficient investments and coordination of care activities limited training opportunities and human resource. A smooth transition between care levels is hampered by procedural, administrative, logistics, infrastructural and socio-economic barriers. Conclusion A coordinated care process established on effective communication across different care levels, referral planning, staff supervision, decreased staff shuffling, routine in-service training, staff motivation and institutional commitment are necessary to achieve an effective care continuum for LBW infants and their families. | Health-system drivers influencing the continuum of care linkages for low-birth-weight infants at the different care levels in Ghana | 10.1186/s12887-023-04330-5 |
2023-10-05 | Background Temporomandibular joint (TMJ) arthritis is a debilitating, challenging condition and different methods have been implicated for its treatment. This study aimed to test the therapeutic potentials of low-level laser therapy (LLLT) associated with adipose derived stem cells (ADSC) or their derived secretome on a murine model induced arthritis. Methods Forty eight rats were divided into four groups where group I was the sham control, the rest of animals were subjected to arthritis induction using complete Freund’s adjuvant, then divided as follows: group II received phosphate buffered saline (PBS) intraarticular injection and irradiation of 0 j/cm2, group III received ADSCs derived secretome and irradiation of 38 j/cm2, and group IV received ADSCs and irradiation of 38 j/cm2 as well. One and three weeks after treatment, animals were euthanized, and paraffin blocks were processed for histological assessment by hematoxylin and eosin stain with histomorphometrical analysis. Histochemical evaluation of joint proteoglycan content was performed through toluidine blue stain, and immunohistochemical staining by the proinflammatory marker tumor necrosis factor-α (TNF-α) was performed followed by the relevant statistical tests. Results The arthritis group showed histological signs of joint injury including cartilage atrophy, articular disc fibrosis, irregular osteochondral interface, and condylar bone resorption together with high inflammatory reaction and defective proteoglycan content. In contrast, the treated groups III and IV showed much restoration of the joint structure with normal cartilage and disc thickness. The inflammation process was significantly suppressed especially after three weeks as confirmed by the significant reduction in TNF-α positive immunostaining compared to the arthritic group, and the cartilage proteoglycan content also showed significant increase relative to the arthritic group. However, no significant difference between the results of the two treated groups was detected. Conclusion LLLT conjugated with ADSCs or ADSCs derived secretome can efficiently enhance the healing of arthritic TMJs. Stem cell secretome can be applied as a safe, potent therapy. However, further investigations are required to unravel its mechanism of action and pave its way as a safe, novel, cell free therapy. Graphical Abstract | Photobiostimulation conjugated with stem cells or their secretome for temporomandibular joint arthritis in a rat model | 10.1186/s12903-023-03466-1 |
2023-10-04 | This work presents a damage index proposal based on an experimental approach to evaluate the behavior of laminated fiber-reinforced composite plates under in-plane shear-after-impact conditions. Therefore, drop-weight experimental tests for low-energy impact (face-on in the barely visible impact damage range) are performed in laminates, as well as in-plane shear tests are carried out by 3-rail device to obtain stress–strain curves for pristine and impact-damaged composite plates. A new coupon based on the ASTM standards is designed to fit impact and in-plane shear experimental devices. The phenomenological damage index for shear-after-impact is energy-based being able to quantify the damage severity in the composite plates as shown by experimental results. Simple guidelines for its determination are also summarized. Furthermore, computational simulations via ABAQUS with a User Material (UMAT) subroutine accounting for progressive damage analysis are performed to predict damage index values for different degradation scenarios. Finally, it is discussed and concluded that the proposed damage index and the experimental approach can be combined with the already consolidated procedures, such as flexure- and compression-after-impact, to evaluate with more accuracy the residual strength of impacted laminates of fiber-reinforced composite materials. | A damage index proposal for shear-after-impact of laminated composite plates | 10.1007/s40430-023-04475-5 |
2023-10-03 | In this paper, we perform the fast rotation limit $$\varepsilon \rightarrow 0^+$$ ε → 0 + of the density-dependent incompressible Navier–Stokes–Coriolis system in a thin strip $$\Omega _\varepsilon :=\,{\mathbb {R}}^2\times \, \left. \right] -\ell _\varepsilon ,\ell _\varepsilon \left[ \right. \,$$ Ω ε : = R 2 × - ℓ ε , ℓ ε , where $$\varepsilon \in \,\left. \right] 0,1\left. \right] $$ ε ∈ 0 , 1 is the size of the Rossby number and $$\ell _\varepsilon >0$$ ℓ ε > 0 for any $$\varepsilon >0$$ ε > 0 . By letting $$\ell _\varepsilon \longrightarrow 0^+$$ ℓ ε ⟶ 0 + for $$\varepsilon \rightarrow 0^+$$ ε → 0 + and considering Navier-slip boundary conditions at the boundary of $$\Omega _\varepsilon $$ Ω ε , we give a rigorous justification of the phenomenon of the Ekman pumping in the context of non-homogeneous fluids. With respect to previous studies (performed for flows of contant density and for compressible fluids), our approach has the advantage of circumventing the complicated analysis of boundary layers. To the best of our knowledge, this is the first study dealing with the asymptotic analysis of fast rotating incompressible fluids with variable density in a 3-D setting. In this respect, we remark that the case $$\ell _\varepsilon \geqslant \ell >0$$ ℓ ε ⩾ ℓ > 0 for all $$\varepsilon >0$$ ε > 0 remains largely open at present. | Fast Rotating Non-homogeneous Fluids in Thin Domains and the Ekman Pumping Effect | 10.1007/s00021-023-00826-3 |
2023-10-01 | In Carbon Capture and Storage (CCS) procedures, it is important to determine the stability of the wellbore during carbon dioxide (CO 2 ) injection and part of this involves assessing stresses on the rock near the wellbore due to changes in temperature and pressure. To address this, this study investigated the influence of cooling on the mechanical properties of a sandstone typical of those found in the central and southern North Sea. A series of uniaxial and triaxial compression tests was conducted on dry and saturated sandstone samples to determine the effects of cooling on the strength and stiffness under different confining pressures. The elastic modulus, shear modulus, bulk modulus and Poisson’s ratio were determined for three temperature conditions and three pressures representing different depths in a wellbore. Two methods, the International Society of Rock Mechanics (ISRM) and Wood’s (Soil behaviour and critical state soil mechanics. Cambridge University Press, Cambridge, 1990), were used to determine the mechanical properties of the rock during the Uniaxial Compressive Strength (UCS) tests. For the triaxial test, only Wood’s (1990) method was applied due to the existence of confining pressure. Microstructural analysis on thin sections of the sandstones under plane and crossed polarised light conditions in the deformed and undeformed state was conducted to elucidate deformation mechanisms and aid interpretation of experimental results. It was identified that both an increase in confinement and a reduction in temperature, increased the strength of the sandstone and reduced the Poisson’s ratio. Additionally, by decreasing the temperature, especially in the UCS test the material dilated less. This is an important outcome as expanding the results to a wellbore stability problem, brittle behaviour may be more apparent and damage may occur when sub-zero injection temperatures are applied, especially at the wellbore head, where confinement is low. UCS and triaxial tests on Stainton Sandstone at 15 ℃, − 5 ℃ and − 10 ℃ were used to determine the influence of temperature drop on Poisson’s ratio and different mechanical moduli. Wood’s ( 1990 ) method for determining the mechanical properties of rock using critical state mechanics can also be applicable to UCS tests. Microscopic analysis of sandstone sample before and after the UCS and triaxial tests indicated dilation and grain realignment, which result in Poisson’s ratios greater than 0.5. Expanding the experimental results to CCS challenges, the wellbore head is the most vulnerable to sub-zero temperatures due to lack of confinement. | The Effects of Cooling on Fine-Grained Sandstone in Relation to Wellbore Injection of Carbon Dioxide | 10.1007/s00603-023-03446-5 |
2023-10-01 | In this work, one type of axially chiral materials with both blue-emissive ultralong organic phosphorescence (UOP) and intense circularly polarized luminescence (CPL) is reported. Such materials not only exhibit extremely small energy gap between the S1 and T1 states (Δ E ST , 0.03 eV), greatly promoting the intersystem crossing process for more triplet excitons, but also show ultralong phosphorescent lifetime (5.5 s). As a result, a bright blue afterglow of up to 60 s is achieved in 2-methyltetrahydrofuran at 77 K. The “exciton hourglass” model is further proposed to describe the internal photophysical processes. Moreover, such UOP materials also exhibit intense CPL because of the rigid axially chiral skeleton. Impressively, the luminescence asymmetry factor ( g lum ) value of up to 0.34 can be achieved by applying them as the chiral inducers for liquid crystal materials. This work can provide a guideline and perspective for further designing novel pure organic molecules with both UOP and intense CPL. 本文报道了一类兼具超长有机磷光(UOP)和强圆偏振发光(CPL)性质的蓝光轴手性材料. 这类材料不仅具有极小的单重态(S1)-三重态(T1)能隙差(Δ E ST , 0.03 eV), 能够极大地促进系间窜越过程以产生更多的三重态激子, 而且还具有超长的磷光衰减寿命(5.5 s). 因此, 这类材料在77 K下的2-MeTHF稀溶液中显示长达60 s的亮蓝色余辉. 我们进一步提出了“激子沙漏”模型来描述内部的光物理过程和解释产生超长余辉的原因. 此外, 由于刚性的轴手性骨架, 这类UOP材料还表现出强的CPL活性, 尤其是将它们用作液晶材料的手性诱导剂时, 能够获得0.34的 g lum 值. 本工作对于进一步设计兼具UOP和强CPL性质的新型纯有机分子材料具有重要的指导意义. | Axially chiral materials exhibiting blue-emissive ultralong organic phosphorescence and intense circularly polarized luminescence | 10.1007/s40843-023-2551-y |
2023-10-01 | Abstract Dynamic mechanical analysis is used to perform comparative low-cycle fatigue tests according to the scheme of bending the weld metal of a low-carbon steel 22K welded joint after a high-temperature action according to the following schedule: holding at 1200°C for 3.7 h followed by slow cooling. The weld metal in the initial state is shown to be characterized by low-cycle fatigue high resistance: the fatigue limit for finite life at N = 3.5 × 10 4 cycles is σ RN = 340 MPa. The high-temperature action additionally increases σ RN by 23%. The influence of the microstructure of the weld on the fatigue strength characteristics and fracture mechanisms is analyzed. | Low-Cycle Fatigue of the Weld Metal of a Low-Carbon Steel Welded Joint after High-Temperature Action | 10.1134/S0036029523100257 |
2023-10-01 | B 2 O 3 -ZnO-SiO 2 (BZS) glass containing CuO with excellent acid resistance, wetting properties, and high-temperature sintering density was prepared by high temperature melting method and then applied in copper terminal electrode for multilayer ceramic capacitors (MLCC) applications. The structure and property characterization of B 2 O 3 -ZnO-SiO 2 glass, including X-ray diffraction, FTIR, scanning electron microscopy, high-temperature microscopy, and differential scanning calorimetry, indicated that the addition of CuO improved the glass’s acid resistance and glass-forming ability. The wettability and acid resistance of this glass were found to be excellent when CuO content was 1.50 wt%. Compared to BZS glass, the CuO-added glass exhibited excellent wettability to copper powder and corrosion resistance to the plating solution. The sintered copper electrode films prepared using the glass with CuO addition had better densification and lower sintering temperature of 750 °C. Further analysis of the sintering mechanism reveals that the flowability and wettability of the glass significantly impact the sintering densification of the copper terminal electrodes. | Preparation of B2O3-ZnO-SiO2 Glass and Sintering Densification of Copper Terminal Electrode Applied in Multilayer Ceramic Capacitors | 10.1007/s11595-023-2783-4 |
2023-10-01 | In this study, a novel AI-based modeling approach is introduced to estimate high-fidelity heat transfer calculations and predict thermal distortion in metal additive manufacturing, specifically for the multi-laser powder bed fusion (ML-PBF) process. The effects of start position and printing orientation on deformation and stress distribution in parts produced using the ML-PBF additive manufacturing process are investigated. A total of 512 simulations are executed, and the maximum and minimum deformation values are recorded and compared. A significant reduction, e.g., 53% in deformation, is observed between the best and worst printing cases. A low-fidelity modeling framework, based on a feedforward neural network, is developed for the rapid prediction of thermal displacement with high accuracy. The model with unknown test cases demonstrates a strong positive correlation ( R = 0.88) between the high-fidelity and network-predicted low-fidelity outputs. The simplicity, computational efficiency, and ease of use of the developed model make it a valuable tool for preliminary evaluation and optimization in the early stages of the design process. By adjusting controlling factors and identifying trends in thermal history, the model can be scaled to a high-fidelity model for increased accuracy, significantly reducing development time and cost. The findings of this study provide valuable insights for designers and engineers working in the field of additive manufacturing, offering a better understanding of deformation/thermal displacement control and optimization in the ML-PBF process. | AI modeling for high-fidelity heat transfer and thermal distortion forecast in metal additive manufacturing | 10.1007/s00170-023-11974-1 |
2023-10-01 | The turbine section of turbojet engines operates above 900 °C. The cast Ni-based superalloy blades and vanes are used in this section. These components which are working in a very aggressive environment are usually applied with diffusion coatings. These coatings are used to increase oxidation resistance of parts and have evolved from plain aluminide coating to platinum-doped coating. Although the positive effect of platinum–aluminide coatings on the oxidation resistance of the superalloys is reported in several studies, the influence of this type of coatings on the mechanical properties of superalloys is somewhat challenging. This tutorial review of Pt–Al coatings covers: how they supply protection against cyclic oxidation, how they are employed, their microstructure characterization, and their influence on the mechanical behavior of Ni-based superalloys. The present review tries to collect all the available information on the subject and seeks the optimum correlation between Pt–Al coating characterization and mechanical/cyclic oxidation behavior of the coated superalloys. | A review on the Cyclic Oxidation Behavior and Mechanical Properties of the Pt–Al-Coated Cast Ni-based Superalloys | 10.1007/s40962-023-00984-0 |
2023-10-01 | High temperature in diffusion bonding (DB) process severely deteriorates the performance of zirconium (Zr) R60702 in extreme chemical environment. Therefore, it is important to reduce the DB temperature of Zr R60702. In this work, low-temperature diffusion bonding of Zr R60702 at 750 °C is realized by 0.3 wt% hydrogen addition while 900 °C is required in DB process for unhydrogenated Zr R60702. The shear strength of the hydrogenated joint bonded at 750 °C reaches 388 MPa, which is 117.98% higher than that of the unhydrogenated joint bonded at 750 °C and equal to that of the unhydrogenated joint bonded at 900 °C. The effects of hydrogen addition in Zr R60702 on the microstructure evolution, phase transformation temperature, interatomic bonding and self-diffusion coefficient of Zr atoms are investigated in detail. The results show that the optimized DB properties can be attributed to the improvements of its grain boundary diffusion, plasticity and self-diffusion coefficient of Zr atoms. | Low-Temperature Diffusion Bonding Behavior of Hydrogenated Zr R60702 | 10.1007/s40195-023-01575-y |
2023-10-01 | The optimization of hot compression technique of as-cast 0Cr23Ni13 stainless steel at high strain rate was discussed, and its corrosion resistance was evaluated after hot compression treatment experimentally. By adjusting the dynamic recrystallization (DRX) ratio of 0Cr23Ni13 stainless steel during hot pressing, the content of low Σ coincident site lattice (ΣCSL) grain boundaries is increased, and the grain orientation is optimized. The results show that ferrite and austenite are completely recrystallized at 1050 and 1150 °C, respectively. The number of grains in the <111> and <101> directions increases significantly, the corrosion potential increases, and the corrosion current density decreases, which will significantly improve the corrosion resistance of 0Cr23Ni13 stainless steel. After the optimization of grain boundary distribution, corrosion resistance is noticeably improved due to the existence of low ΣCSL boundaries. The interference effect of low ΣCSL grain boundary on random grain boundary network becomes intense with the increase in DRX ratio, which is the fundamental measure to improve the corrosion resistance. | Effect of microstructure variation on corrosion properties of as-cast 0Cr23Ni13 stainless steel at high strain rate of hot compression | 10.1007/s42243-023-00918-4 |
2023-10-01 | Background Bell pepper ( Capsicum annuum L.) is one of the most economically and nutritionally important vegetables worldwide. However, its production can be affected by various abiotic stresses, such as low temperature. This causes various biochemical, morphological and molecular changes affecting membrane lipid composition, photosynthetic pigments, accumulation of free sugars and proline, secondary metabolism, as well as a change in gene expression. However, the mechanism of molecular response to this type of stress has not yet been elucidated. Methods and results To further investigate the response mechanism to this abiotic stress, we performed an RNA-Seq transcriptomic analysis to obtain the transcriptomic profile of Capsicum annuum exposed to low temperature stress, where libraries were constructed from reads of control and low temperature stress samples, varying on average per treatment from 22,952,190.5–27,305,327 paired reads ranging in size from 30 to 150 bp. The number of differentially expressed genes (DEGs) for each treatment was 388, 417 and 664 at T-17 h, T-22 h and T-41 h, respectively, identifying 58 up-regulated genes and 169 down-regulated genes shared among the three exposure times. Likewise, 23 DEGs encoding TFs were identified at T-17 h, 30 DEGs at T-22 h and 47 DEGs at T-42 h, respectively. GO analysis revealed that DEGs were involved in catalytic activity, response to temperature stimulus, oxidoreductase activity, stress response, phosphate ion transport and response to abscisic acid. KEGG pathway analysis identified that DEGs were related to flavonoid biosynthesis, alkaloid biosynthesis and plant circadian rhythm pathways in the case of up-regulated genes, while in the case of down-regulated genes, they pertained to MAPK signaling and plant hormone signal transduction pathways, present at all the three time points of low temperature exposure. Validation of the transcriptomic method was performed by evaluation of five DEGs by quantitative polymerase chain reaction (q-PCR). Conclusions The data obtained in the present study provide new insights into the transcriptome profiles of Capsicum annuum stem in response to low temperature stress. The data generated may be useful for the identification of key candidate genes and molecular mechanisms involved in response to this type of stress. | Transcriptomic analysis of bell pepper (Capsicum annuum L.) revealing key mechanisms in response to low temperature stress | 10.1007/s11033-023-08744-3 |
2023-10-01 | Owing to the complexity and variability of global climate, the study of extreme events to ensure food security is particularly critical. The standardized precipitation requirement index (SPRI) and chilling injury index (I Ci ) were introduced using data from agrometeorological stations on the Songliao Plain between 1981 and 2020 to identify the spatial and temporal variability of drought, waterlogging, and low-temperature cold damage during various maize growth periods. Compound drought and low-temperature cold damage events (CDLEs) and compound waterlogging and low-temperature cold damage events (CWLEs) were then identified. To measure the intensity of compound events, the compound drought and low-temperature cold damage magnitude index (CDLMI), and compound waterlogging and low-temperature cold damage magnitude index (CWLMI) were constructed by fitting marginal distributions. Finally, the effects of extreme events of various intensities on maize output were examined. The findings demonstrate that: (1) There were significant differences in the temporal trends of the SPRI and I Ci during different maize growth periods. Drought predominated in the middle growth period (MP), waterlogging predominated in the early growth period (EP) and late growth period (LP), and both drought and waterlogging tended to increase in intensity and frequency. The frequency of low-temperature cold damage showed a decreasing trend in all periods. (2) The CDLMI and CWLMI can effectively determine the intensity of CDLEs and CWLEs in the study area; these CDLEs and CWLEs had higher intensity and frequency in the late growth period. (3) Compared to single events, maize relative meteorological yield had a more significant negative correlation with the CDLMI and CWLMI. | Quantifying Multi-hazards and Impacts Over Different Growth Periods of Maize: A Study Based on Index Construction | 10.1007/s13753-023-00516-8 |
2023-10-01 | Low-dimensional nanomaterials are zero-, one- and two-dimensional nanomaterials, in which the aspect ratio and surface-to-volume ratio vary as the dimension varies. In nanofluids, suspended nanomaterials’ movement in the base fluid can be due to Brownian motion and thermophoresis effect, which causes heat transfer. However, the emergence of nanomaterials with various dimensions has led to more advanced heat transfer mechanisms. The high aspect ratio and surface-to-volume ratio of the nanomaterials are believed to be among the factors in nanofluids’ properties enhancement. However, the morphological effect on the heat transfer enhancement in nanofluids is still ambiguous. Hence, this paper aims to explore this significant gap by reviewing the reports that investigate the effect of morphology to the heat transfer enhancement in nanofluids containing low-dimensional nanomaterials and observe the trend. The heat transfer mechanisms in nanofluids are discussed to improve understanding of the phenomena, including its methods of study. This review also includes the material characterization techniques since these approaches can provide morphological information; hence, heat transfer can be studied. Heat transfer mechanisms associated with the movement of nanoparticles were the most researched mechanism, mostly by experimentations and theoretical predictions. However, there has not been a substantial amount of research linking the morphological studies to the heat transfer enhancement in nanofluids. The study of nanolayer, nanoclustering and phonon heat transport has also been made possible by recent advancements in high-performance computing applications such as molecular dynamics simulation and machine learning, offering a more efficient method for exploring novel low-dimensional nanomaterials beyond zero-dimension. | Low-dimensional nanomaterials for nanofluids: a review of heat transfer enhancement | 10.1007/s10973-023-12372-1 |
2023-10-01 | The TiO 2 photocatalytic coatings’ most important properties are durability and photocatalytic activity. Those features form a basis to determine its degree of usefulness. In this study, the self-synthesized amorphous TiO 2 powder was used for low-pressure cold spray photocatalytic coatings. Two strategies were adopted to change the surface properties, which can influence the mechanical properties of the coatings: (I) reduction of the scanning step and (II) filling the depressions in the already sprayed coating with the second layer. The coatings surface topography (measured by roughness and waviness) results showed that the first strategy makes coatings thicker, with a more uniform surface. The second strategy leads to obtaining more rough surfaces with no significant change in the thickness. The preliminary study results indicate that the first strategy was superior to the other one, in terms of both mechanical (described by cohesion and adhesion) and photocatalytic (measured by the decomposition of methylene blue under UV) properties of the coatings. Graphical Abstract | Preliminary Study on Low-Pressure Cold Spray Process Parameters: Effect on Mechanical and Photocatalytic Properties of TiO2 Coatings | 10.1007/s11666-023-01615-0 |
2023-10-01 | In this study, friction stir welding was carried out with varying tool rotational speed from 300 to 750 rpm at a fixed tool traverse speed of 60 mm/min and 2° tool tilt angle. The main aim of this work is to investigate the influence of the tool rotational speed on the welding metallurgy, mechanical property, and electrochemical behavior of friction stir welded joints. Small and more or less equiaxed grains were observed in the stir zone. However, the thermo-mechanical affected zone exhibits elongated grains, and the heat-affected zone evolved almost similar but reduced-sized grains as compared to the base metal. The grain size variations directly affected the mechanical properties. With an increase in tool rotational speed, the microhardness values were decreased and a maximum microhardness value of ~ 220.9 VHN was obtained at the stir zone of the 300 rpm welded sample. In addition to the microhardness test, uniaxial tensile tests were conducted to determine the strength of the welded samples. The maximum ultimate tensile strength of ∼341 MPa was found on the sample welded with 600 rpm tool rotational speed. The fracture morphology of the samples indicated ductile fracture. However, the samples welded with lower rotational speeds were found to be less ductile as the sizes of micro-voids are more, compared to the sample welded with 600 and 750 rpm tool rotational speeds. The corrosion behavior of the different zones of the welded joints with 0.1 M HCl solution shows that the corrosion rate decreases with increasing tool rotational speed. | Effect of rotational speed on microstructure, mechanical property, and electrochemical behavior of friction stir welded joint of ultra-low carbon steel | 10.1007/s40194-023-01565-9 |
2023-10-01 | Coupling effects of fretting wear and cyclic stress could result in significant fatigue strength degradation, thus potentially causing unanticipated catastrophic fractures. The underlying mechanism of microstructural evolutions caused by fretting wear is ambiguous, which obstructs the understanding of fretting fatigue issues, and is unable to guarantee the reliability of structures for long-term operation. Here, fretting wear studies were performed to understand the microstructural evolution and oxidation behavior of an α/β titanium alloy up to 10 8 cycles. Contact surface degradation is mainly caused by surface oxidation and the generation of wear debris during fretting wear within the slip zone. The grain size in the topmost nanostructured layer could be refined to ∼40 nm. The grain refinement process involves the initial grain rotation, the formation of low angle grain boundary (LAGB; 2°–5°), the in-situ increments of the misorientation angle, and the final subdivision, which have been unraveled to feature the evolution in dislocation morphologies from slip lines to tangles and arrays. The formation of hetero microstructures regarding the nonequilibrium high angle grain boundary (HAGB) and dislocation arrays gives rise to more oxygen diffusion pathways in the topmost nanostructured layer, thus resulting in the formation of cracking interface to separate the oxidation zone and the adjoining nanostructured domain driven by tribological fatigue stress. Eventually, it facilitates surface degradation and the formation of catastrophic fractures. | Microstructural evolution and oxidation in α/β titanium alloy under fretting fatigue loading | 10.1007/s40544-022-0729-z |
2023-10-01 | Poor atomization and ignition difficulty due to the deterioration of environmental conditions restrict the cold-start performance of diesel engine. To investigate how the ambient and injection parameters affect diesel ignition characteristics at low temperature and density, liquid spray development was measured by back-illumination method; vapor spray and ignition process were visualized using high-speed shadowgraph method in constant volume combustion chamber. The results showed that liquid-vapor penetration and two-stage ignition delay have different sensitivities to variables: the variation of ambient density greatly affects the spray development while ambient temperature is the most significant parameter affecting ignition delay. Additionally, the change of injection pressure cannot cause significant change of both liquid penetration length and low temperature ignition, but increasing injection pressure promoted the vapor penetration length downstream development. Based on the data obtained, the empirical formulation in the form of power function was fitted for the stable stage of liquid penetration length, which proposed a reference for comparing the liquid phase development characteristics of diesel spray. Similarly, revise the Arrhenius-type ignition delay prediction formula and the correction coefficient K ( K LTI and K HTI ) was optimized quantitatively instead of fixed values, provides a preliminary theoretical basis for subsequent diesel spray model. | Optical Study on Spray and Two-Stage Ignition Characteristics for Diesel Spray Under Low Ambient Temperature and Density Conditions | 10.1007/s12239-023-0101-y |
2023-10-01 | Low-carbon methane (CH 4 ) obtained from CO 2 hydrogenation is a promising option for reducing greenhouse gases (GHG) emissions from carbon-intensive fossil fuel-based energy production, but catalytic performance, especially in low temperatures, still needs to be improved before large-scale implementation. In this work, it is proposed the use of hydroxyapatite (HAP) as an alternative catalyst support to validate its performance for CO 2 hydrogenation to CH 4 . In addition, for the first time in literature, the influence of process conditions (temperature, gas hourly space velocity and Ni metal load) on the performance of HAP-supported catalysts is investigated on semi-pilot scale. CO 2 conversion is favored up to 400 °C, despite the thermodynamic limitations of the hydrogenation reaction. Ni-based catalysts present the best performance for CO 2 hydrogenation with a maximum CO 2 conversion around 88% under optimized conditions (20 wt.% Ni, T = 350 °C, GHSV = 320 h −1 ) with 100% CH 4 selectivity and no CO production up to 450 °C. Finally, long-term operation of 20Ni/HAP for 50 h on semi-pilot scale shows a robust performance with 83% CO 2 conversion, 100% CH 4 selectivity and no signs of catalyst deactivation. The performance HAP-based catalyst presented here demonstrates the feasibility of HAP as alternative catalyst support for CO 2 hydrogenation and the potential for process upscaling with HAP-supported catalysts. Graphical Abstract | Performance of Hydroxyapatite-Supported Catalysts for Methane Production Via CO2 Hydrogenation on Semi-Pilot Scale | 10.1007/s12649-023-02106-7 |
2023-10-01 | This study aimed to determine the temperature variation strategies in the first 30 days in dynamic controlled atmosphere storage based on respiratory quotient 1.3 (DCA-RQ 1.3) on the quality maintenance of ‘Maxi Gala’ apples after long-term storage plus extended shelf life (7 and 14 days). ‘Maxi Gala’ apples were harvested in two growing seasons, in 2019 (first season) and 2020 (second season). ‘Maxi Gala’ apples were stored under a controlled atmosphere with ultra-low oxygen (CA/ULO), CA/ULO + 1‑methylcyclopropene (CA/ULO + 1‑MCP) at 2.0 °C in the two growing seasons, and DCA-RQ 1.3 under constant temperatures of 0.5, 2.0 (first season), 1.0, and 2.5 °C (second season) and temperature variation strategies of (0.5 → 2.0), (2.0 → 0.5) in 2019, and in 2020 of (1.0 → 2.5) and (2.5 → 1.0) °C. Fruit stored under DCA-RQ 1.3 with constant temperatures of 2.0 and 2.5 °C and temperature variation of (2.0 → 0.5) and (1.0 → 2.5) °C showed high flesh firmness and the highest healthy fruit amount due to the lowest mealiness and flesh breakdown incidence compared to CA/ULO and CA/ULO + 1‑MCP after 7 and 14 days shelf life. Fruit stored under DCA-RQ 1.3 at 1.0 °C showed lower flesh firmness and healthy fruit amount due to highest mealiness, flesh breakdown, and decay after 7 and 14 days at 20 °C. In conclusion, DCA-RQ 1.3 at 2.0 and 2.5 °C keeps fruit with high physicochemical quality for long-term storage, prolonging shelf life for up to 14 days at 20 °C. Temperature variation strategies do not provide additional benefits to physicochemical quality compared to constant temperature (2.0–2.5 °C). | Temperature Variation During Dynamic Controlled Atmosphere Storage: Effects on the Quality of ‘Maxi Gala’ Apples | 10.1007/s10341-023-00872-1 |
2023-10-01 | The ultra-fine grained (UFG) pure titanium was prepared by equal channel angular pressing (ECAP) and rotary swaging (RS). The strain controlled low cycle fatigue (LCF) test was carried out at room temperature. The fatigue life prediction model and mean stress relaxation model under asymmetrical stress load were discussed. The results show that the strain ratio has a significant effect on the low cycle fatigue performance of the UFG pure titanium, and the traditional Manson-coffin model can not accurately predict the fatigue life under asymmetric stress load. Therefore, the SWT mean stress correction model and three-parameter power curve model are proposed, and the test results are verified. The final research shows that the three-parameter power surface model has better representation. By studying the mean stress relaxation phenomenon under the condition of R ≠−1 it is revealed that the stress ratio and the strain amplitude are the factors that significantly affect the mean stress relaxation rate, and the mean stress relaxation model with the two variables is calculated to describe the mean stress relaxation phenomenon of the UFG pure titanium under different strain ratios. The fracture morphology of the samples was observed by SEM, and it was concluded that the final fracture zone of the fatigue fracture of the UFG pure titanium was a mixture of ductile fracture and quasi cleavage fracture. The toughness of the material increases with the increase of strain ratio at the same strain amplitude. | Effect of Strain Ratio on Fatigue Model of Ultra-fine Grained Pure Titanium | 10.1007/s11595-023-2806-1 |
2023-10-01 | A complex of comparative studies on static fracture toughness according to the three-point bending scheme was carried out for the 22K low-carbon steel (AISI 1022) after various heat treatment, namely after normalization, after prolonged heat treatment provoking temper brittleness (TO-1 regime included heating to 650 °C and slow stepwise cooling for 7 days), and after high-temperature heat treatment causing intensive grain growth (TO-2 regime included heating to 1200 °C with holding for 3.7 h). The criterion of non-linear fracture mechanics, namely the critical J -integral taking into account plastic deformation at the crack tip was used as a characteristic of fracture toughness. It is shown that, regardless of the type of structure formed by different heat treatment, the 22K steel is characterized by high fracture toughness. However, after heat treatment by the TO-1 and TO-2 regimes, the value of the critical J -integral decreases by 23 and 30%, respectively. | Fracture Toughness of 22K-Type Low-Carbon Steel After Extreme Thermal Exposure | 10.1007/s11665-022-07746-9 |
2023-10-01 | The development of optical films with high transparency, high thermal resistance and low birefringence remains a challenge in the flexible display industry. In this work, we designed and synthesized a series of fluorinated colorless polyimides (CPIs) materials using 2,5-substituted m -phenylenediamine diamine monomers and 1,2,4,5-cyclohexanetetracarboxylic dianhydride (CHDA). We systematically studied the effects of fluorinated group substitutions on the thermal, mechanical, optical and dielectric properties of CPI films. The introduction of alicyclic CHDA dianhydride affords high transparency and low yellowness, while the 2,5-substituted m -phenylenediamine diamines offer the CPIs with quite low birefringence as well as high glass transition temperatures. A particular CHDA/ o 3FBDA film with simple chemical structure stands out, exhibiting well-balanced overall properties. | Fluorinated Colorless Polyimides with High Heat-resistance and Low Birefringence | 10.1007/s10118-023-3011-6 |
2023-10-01 | To promote the green and sustainable development of the foundry industry, it is necessary to further explore the new method, new technology, and new equipment for green foundry. In this paper, an innovative green casting method is proposed. The digital frozen sand casting technology uses water as the binder to replace the organic/inorganic binder for casting at low temperature, which solves the problems of difficult sand recovery and harmful gas emission during the casting process and realizes the high-performance green casting of complex castings. The green casting technology of digital frozen sand mold is a method to produce sand mold by freezing cutting and printing, and to obtain typical parts by mold assembling and pouring. In this paper, the basic theory, key technologies, and system equipment of frozen sand paving are systematically studied, and the application verification research is carried out on typical aluminum alloy parts. It reduced the amount of resin binder, improved the green level of casting industry, and provided a new green casting method for the casting field. | Research on Green Casting Technology and Equipment of Digital Frozen Sand Mold | 10.1007/s40962-023-00972-4 |
2023-10-01 | The paper presents original results regarding the effect of long-term treatment of phlogopite concentrate with nitric acid on the phase ratio, chemical composition and catalytic activity of copper–palladium complexes in the reaction of carbon monoxide oxidation with air oxygen. Phlogopite concentrate is polyphasic and contains phases of phlogopite, clinochlore, diopside and tremolite. Samples were modified with 8M HNO 3 at room temperature for 1; 24; 48; 72 h (8H-Phl-τ). Samples of 8H-Phl-τ ( $$\stackrel{\mathrm{-}}{\text{S}}$$ S - ) and Pd(II)–Cu(II)/ $$\stackrel{\mathrm{-}}{\text{S}}$$ S - catalysts were characterized by XRD, SEM, FT-IR spectroscopy and pH metric methods. It is shown that the content of the phlogopite phase decreases in a number of these samples, while the content of the clinochlore phase increases. The content of diopside and tremolite phases varies irregularly and remains within the limits for the original sample. Long-term acid modification (72 h) leads to amorphization of the sample and the formation of nanosilica: the silicon content increases to 92 wt. % . The Wacker-type catalyst fixed on nanosilica showed a high degree (97%) of carbon monoxide conversion. | Catalyst containing natural nanosilica, palladium(II) and copper(II) salts in oxidation of carbon monoxide with oxygen | 10.1007/s13204-023-02772-y |
2023-10-01 | Aqueous supercapacitors are promising electrochemical energy storage devices for research nowadays due to their intrinsic high safety, low cost and high power density. However, the freezing of water at low temperatures limits the scope of application of aqueous devices. Here, we report a dilute hybrid electrolyte with low-temperature performance by introducing ethylene glycol (EG) as an organic additive for mixed electrolysis at a low concentration of 1 m (mol kg −1 ) Mg(ClO 4 ) 2 . The results show that EG can break the hydrogen bonding between water molecules to prevent the electrolyte from solidifying at low temperatures. The optimized electrolyte has a low freezing point below -50 ℃, which allows the assembled supercapacitor being able to operate at extreme low temperature environments. And it was worth mentioned that the addition of EG could effectively enhance the long-cycle performance of the devices and the assembled supercapacitor can operate stably for more than 30,000 cycles at -30 ℃ and delivered a capacitance of 22.5 F g −1 with a capacitance retention rate of 89% after completion of the cycling. | A low-cost dilute aqueous hybrid electrolyte for low-temperature supercapacitors | 10.1007/s10008-023-05579-7 |
2023-10-01 | The separator is a key component of sodium-ion battery, which greatly affects the electrochemical performances and safety characteristics of the battery. Conventional glass fiber separator cannot meet the requirements of large-scale application because of high cost and poor mechanical properties. Herein, the novel composite separators are prepared by a simple slurry sieving process using glass fiber separator scraps and ordinary qualitative filter paper as raw materials. As the composite mass ratio is 1:1, the composite separator has excellent comprehensive properties, including tensile strength of 15.8 MPa, porosity of 74.3%, ionic conductivity of 1.57 × 10 −3 S·cm −1 and thermal stability at 210°C. The assembled sodium-ion battery shows superior cycling performance (capacity retention of 94.1% after 500 cycles at 1C) and rate capacity (retention rate of 87.3% at 10C), and it maintains fine interface stability. The above results provide some new ideas for the separator design of high-performance and low-cost sodium-ion batteries. | Efficient utilization of glass fiber separator for low-cost sodium-ion batteries | 10.1007/s12613-023-2691-9 |
2023-10-01 | In technical terms, wood is a natural composite material with a polymer matrix, reinforced with fibres made of uniaxially oriented longitudinal cells. Due to the ease of obtaining and relatively low technological requirements related to its processing, wood is a common material used for various types of construction materials. An experimental investigation was carried out to determine the evolution of the ignition sensitivity and the explosion of three types of softwood dusts. Two of those dusts come from conifers and one from a deciduous tree. Complete fire characteristic requires several parameters describing wood dust behaviour under fire conditions including heat release rate (HRR), ignition time, or fire growth index. To determine those parameters, a cone calorimeter was used. Explosion characteristic was tested for representative wood as a dust sample in 20-L spherical vessel. Minimum ignition energy (MIE) was tested on MINOR II apparatus, which is a modified Hartman’s tube. Minimum ignition temperatures were tested with the use of layer ignition temperature apparatus and Godbert–Greenwald apparatus for minimum ignition temperature of a dust layer and dust cloud (MIT), respectively. Dust with the highest K ST value, lowest MIE in the widest concentration range, and lowest MIT was pine wood dust. It also shows the shortest ignition time and a timespan between ignition and HRR peak. | Flammability and explosion characteristics of softwood dust | 10.1007/s10973-023-12453-1 |
2023-10-01 | Abstract The development of a refined conceptual model for the generation of volcanic-related uranium deposits includes studies in the character of magmatic, hydrothermal-metasomatic, and filtration-transport processes, as well as of the physicochemical conditions favoring the transport and deposition of uranium. We consider these issues using the examples of the Streltsovka caldera and the eponymous ore field in eastern Transbaikalia, the Xiangshan volcanic structure in South China, and the McDermitt caldera in the western United States (Oregon and Nevada). According to the IAEA classification ( Geological Classification …, 2018), these ore fields and deposits are of the volcanic-related type, while the Streltsovka and the Xiangshan ore field show a combination of the volcanic-related type in the volcanic-sedimentary cover and the granite-related type at the basement. Most industrially viable uranium deposits of the volcanic-related type were formed in the regions listed above during Mesozoic and Cenozoic times (although we know of older, Paleozoic objects of the type). Although the time spans in which ore-bearing volcanic-related edifices were formed are different, many features in the occurrence of magmatic, hydrothermal, and filtration transport processes in these edifices are rather similar. It is commonly supposed that these features are due to a common effect of intraplate tectonic regimes or to the evolution of outer parts in the ocean-continent zones where magmatic activity produced volcanism of the bimodal series in the dominant basites–acid volcanics–basites sequence, while the migration of uranium-transporting fluids was controlled by a joint action of seismogeodynamic and thermal convective processes. | The Character of Magmatism, Hydrothermal-Metasomatic, and Filtration-Transport Processes in Uranium-Bearing Volcanic-Related Structures | 10.1134/S0742046323700306 |
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