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Flow cytometry bioinformatics In manual analysis, prior biological knowledge (e.g., biological controls) provides guidance to reasonably identify these populations. However, integrating this information into the exploratory clustering process (e.g., as in semi-supervised learning) has not been successful. An alternativ... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics Alternatively, all the cells from the entire cohort can be pooled into a single multidimensional space for clustering before classification. This approach is particularly suitable for datasets with a high amount of biological variation (in which cross-sample matching is challenging) but re... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics This enables the removal of unnecessary markers and provides a simple visualization of all identified cell types. In a recent analysis of a large (n=466) cohort of HIV+ patients, this pipeline identified three correlates of protection against HIV, only one of which had been previously iden... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics The Archival Cytometry Standard (ACS) is being developed to bundle data with different components describing cytometry experiments. It captures relations among data, metadata, analysis files and other components, and includes support for audit trails, versioning and digital signatures. The... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics In addition, it includes dozens of built in public transformations that have been shown to potentially useful for display or analysis of cytometry data. In 2013, Gating-ML version 2.0 was approved by ISAC's Data Standards Task Force as a Recommendation. This new version offers slightly les... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics AutoGate performs compensation, gating, preview of clusters, exhaustive projection pursuit (EPP), multi-dimension scaling and phenogram, produces a visual dendogram to express HiD readiness. It is free to researchers and clinicians at academic, government, and non-profit institutions. The ... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics Much of the functionality of the Bioconductor packages for flow cytometry analysis has been packaged up for use with the GenePattern workflow system, in the form of the GenePattern Flow Cytometry Suite. FACSanadu is an open source portable application for visualization and analysis of FCS ... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics A subset of these datasets representing the existing data analysis challenges is described below. For comparison against manual gating, the FlowCAP-I project has released five datasets, manually gated by human analysts, and two of them gated by eight independent analysts. The FlowCAP-II pr... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics Variability across flow cytometry experiments arises from biological variation among samples, technical variations across instruments used, as well as methods of analysis. In 2010, a group of researchers from Stanford University and the National Institutes of Health pointed out that while ... | https://en.wikipedia.org/wiki?curid=41282920 |
Elastic recoil detection Elastic Recoil Detection Analysis (ERDA), also referred to as forward recoil scattering (or, contextually, spectrometry), is an Ion Beam Analysis technique in materials science to obtain elemental concentration depth profiles in thin films. This technique is known by several different names. Th... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Moreover, the angle of incidence that an ion beam makes with the sample must also be taken into account for correct analysis of the sample. This is because, depending on this angle, the recoiled atoms will be collected. Although it is not very clear, the assumption for why this technique is not... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Combination of techniques is usually needed in order to obtain correct characterization. When comparing several techniques, important parameters like detection limit, depth resolution and lateral resolution must be taken into account. For this purpose, comparisons of several techniques have bee... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The recoil detector for LI-ERDA typically has a “range foil” which is typically a Mylar foil placed in front of the detector for blocking scattered incident ions but allow lighter recoiling target atoms to pass through to the detector. Usually a 10 µm thick Mylar foil is able to completely stop... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The difference in the name of the technique is only due to the type of ion beam used as a source. The setup and the experimental conditions affect the performances of both of these techniques. Factors such as multiple scattering, and ion beam induced damage must be taken into account before obt... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Telescope detectors are one way to distinguish such elements in the sample as it becomes extremely difficult to separate the elements using a normal detector. The calculations that model this process are relatively simple, assuming projectile energy is in the range corresponding to Rutherford s... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection This will prevent degradation of the detector from the more intense beam energies. The differential elastic recoil cross-section "σ" is given by: where "Z" and "Z" are the atomic numbers of projectile and sample atoms, respectively. For "m/m" «1 and with approximation "m=2Z"; "Z" being the atom... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection This demand of a large acceptance angle, however, is in conflict with the requirement of optimum depth resolution dependency on the detection geometry. In the surface approximation and assuming constant energy loss the depth resolution "δx" can be written: where "S" is the relative energy loss ... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The angular spread can be maintained within this range by contributions from the beam spot size; however, the solid angle geometry of the detector is only 0.04 msr. Therefore, a detector system with large solid angle as well as high depth resolution may enable corrections for the kinematic ener... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Using the following equation, "x"-coordinates of particle positions, as they enter the detector, can be calculated from charges "l" and "r" : Furthermore, the "y"-coordinate is calculated from the following equation due to the position independence of the anode pulses: For transformation of the... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Figure 2, on the left, depicts the interaction of a heavy ion beam striking the sample atoms and the resulting backscattering and recoil ions. Particle accelerators, such as a magnetron or cyclotron, implement electromagnetic fields to achieve acceleration of elements. Atoms must be electricall... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection A hexapole magnet consists of permanent magnets or superconducting coils. The plasma is contained within the magnetic trap that is formed from electric current flowing in solenoids located on the sides of the chamber. A radial magnetic field, exerted by the hexapole magnetic, is applied to the ... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Once the ions have been extracted from the chamber, they are then sent to the cyclotron for acceleration. It is very important that the ion source used is optimal for the experiment being carried out. To perform an experiment in a practical amount of time, the ions provided from the accelerator... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Incorporating an absorber into the experimental set up can be the most difficult to achieve. The stopping of the beam using either direct or scattered methods can only be accomplished without also stopping the light impurity atoms, if it is heavier (beam ions) than the impurity atoms being anal... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The sample ions pass through an entrance window of the detector, and depending on the type of detector used, the signal is converted into a spectrum. In elastic recoil detection analysis, a silicon diode is the most common detector. This type of detector is commonly used, however, there are som... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The longer the TOF for ions, the better the time resolution (equivalent to energy resolution) will be. TOF spectrometers that have an incorporated solid state detector must be confined to small solid angles. When performing HI-ERDA, TOF detectors are often used and/or "∆E/E" detectors-such as i... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The limiting factor on energy resolution using this type of detector is the entrance window, which needs to be strong enough to withstand the atmospheric pressure of the gas, 20-90 mbar. Ultra-thin silicon nitride windows have been introduced, together with dramatic simplifications in the desig... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection If heavy ions are used and detected, the effect of energy loss straggling will be easily surpassed by the energy loss variation, which is a direct consequence of different foil thicknesses. The cathode electrode is divided in two insulated halves, thus information of particle entrance position ... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Generally, the energy spectra of different recoil elements overlap due to finite sample thickness, therefore particle identification is necessary to separate the contributions of different elements. Common examples of analysis are thin films of TiNO-Cu and BaBiKO. TiNO-Cu films were developed a... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Other than Potassium, the lighter elements are clearly separated in the matrix. From the matrix, there is evidence of a strong carbon contamination within the film. Some films showed a 1:1 ratio of K to carbon contamination. For this specific film analysis, the source for contamination was trac... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Physical concepts of two-body elastic scattering are the basis of several nuclear methods for elemental material characterization. The Fundamental aspects in dealing with recoil spectroscopy involves electron back scattering process of matter such as thin films and solid materials. Energy loss ... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Consider an Incoming and outgoing ion beams that are calculated as a function of collisional depth, by considering two trajectories are in a plane perpendicular to target surface, and incoming and outgoing paths are the shortest possible ones for a given collision depth and given scattering and... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Target angle with the collisional plane is taken as α, and path is augmented by a factor of 1/cos α. For the purpose of converting outgoing particle in to collision depth, geometrical factors are chosen. For recoil R(φ, α)is defined as sin L = R(φ, α)L formula_17 For forward scattering of the p... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection To obtain energy path scale We need to evaluate energy variation δE of the outgoing beam of energy E2 from the target surface for an increment δx of collisional depth, here E remains fixed. Evidently this causes changes in path lengths L and L a variation of path around the collision point x is... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection It is defined as the ability of an analytical technique to detect a variation in atomic distribution as a function of depth. The capability to separate in energy in the recoil system arising from small depth intervals. The expression for depth resolution is given as δR = δE/[{S(E)/SK'E(x)}][R(φ... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Final resolution is not coincide with theoretical evaluation such as the classical depth resolution δRx precisely because it results from three terms that escape from theoretical estimations: Straggling: Energy loss of particle in a dense medium is statistical in nature due to a large number of... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The standard deviation ΩB of the energy distribution is given by : ΩB=4π((Ze)NZ∆x Where NZΔx is the number of electrons per unit area over the path length increment Δx. 3. Large fraction of energy loss: for fractional energy loss in the region of 0.2< ΔE/E ≤ 0.8, the energy dependence of stoppi... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The difference in the energy δE of recoil atoms after collision when two types of atoms differ in their masses by a quantity δM is δE/ δM = E (dK’/dM) δE/ δM = 4E(M(M-M)cosφ/(M+M) Mass resolution δMR (≡ δE/ δM). A main limitation of using low beam energies is the reduced mass resolution. The en... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Angular deviation Case 2 In the below figure there is a considerable difference between in the shape area of Gaussian peak (ideal condition) and angularly deviated peak. and α is an angle due to angular deviation of a penetrated ion beam through matter. In the study of Multiple Scattering pheno... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Goudsmit and Saunderson provided a more complete treatment of Multiple Scattering, including large angles. For large angles Goudsmit considered series of Legendre polynomials which are numerically evaluated for distribution of scattering. The angular distribution from Coulomb scattering has bee... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection ERDA, in general, has many applications in the areas of polymer science, material science – semiconductor materials, electronics, and thin film characterization. ERDA is widely used in polymer science. This is because polymers are hydrogen-rich materials which can be easily studied by LI-ERDA. ... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Several mathematical operations were then performed, electronically, to obtain a concentration versus depth-profile as shown below in figure 17. Please refer to the source for detailed explanation of the mathematical equations. In addition to all these applications, ERDA is one of the methods t... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Green and Russel have studied the segregation of deuterated polystyrene/polymethamethacrylate copolymer at the interface of polystyrene, and polymethylmethacrylate homopolymer at the interface of polystyrene and polymethylmetacrylate homopolymer using ERDA with 2.8 MeV 4He+ ions. They also stud... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection Ion implantation is a technique by which the ions of a material are accelerated in an electrical field and impacted into a materials such that ion are inserted into this material. This technique has many important uses. One such example is the introduction of silver plasma into the biomedical t... | https://en.wikipedia.org/wiki?curid=2321375 |
Elastic recoil detection The profile of impurities can be found in a one-shot measurement at a constant incident energy. Moreover, this technique offers an opportunity to study the density profiles of hydrogen, carbon and oxygen in various materials, as well as the absolute hydrogen, carbon and oxygen content. Combinat... | https://en.wikipedia.org/wiki?curid=2321375 |
Molecules (journal) Molecules is a peer-reviewed open access scientific journal that focuses on all aspects of chemistry and materials science. It was established in March 1996 and is published monthly by MDPI. From 1997 to 2001, "Molbank" was published as a section of the journal, before splitting into its own journal... | https://en.wikipedia.org/wiki?curid=2322122 |
Piperacillin is a broad-spectrum β-lactam antibiotic of the ureidopenicillin class. The chemical structure of piperacillin and other ureidopenicillins incorporates a polar side chain that enhances penetration into gram-negative bacteria and reduces susceptibility to cleavage by gram-negative beta lactamase enzymes. The... | https://en.wikipedia.org/wiki?curid=2322131 |
Piperacillin Piperacillin-tazobactam is recommended as part of a three drug regimen for the treatment of hospital-acquired pneumonia suspected as being due to infection by multi-drug resistant pathogens. It is also one of several antibacterials recommended for the treatment of infections known to be caused by anaerobic... | https://en.wikipedia.org/wiki?curid=2322131 |
Drahoslav Lím (born September 30, 1925 in Czechoslovakia; died August 22, 2003 in San Diego, California) was a Czech chemist. He invented polyhydroxyethylmethacrylate, the synthetic material used for soft contact lenses (hydrogel). Lím worked as a member of the team of Otto Wichterle (the inventor of soft contact lense... | https://en.wikipedia.org/wiki?curid=2322656 |
Metallography is the study of the physical structure and components of metals, by using microscopy. Ceramic and polymeric materials may also be prepared using metallographic techniques, hence the terms ceramography, plastography and, collectively, materialography. The surface of a metallographic specimen is prepared by... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography A typical mounting cycle will compress the specimen and mounting media to and heat to a temperature of . When specimens are very sensitive to temperature, "cold mounts" may be made with a two-part epoxy resin. Mounting a specimen provides a safe, standardized, and ergonomic way by which to hold a sample d... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography , a metal with a hexagonal-closed packed crystal structure, such as Ti or Zr) the microstructure can be revealed without etching using crossed polarized light (light microscopy). Otherwise, the microstructural constituents of the specimen are revealed by using a suitable chemical or electrolytic etchant. ... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography Light microscopes are designed for placement of the specimen's polished surface on the specimen stage either upright or inverted. Each type has advantages and disadvantages. Most LOM work is done at magnifications between 50 and 1000X. However, with a good microscope, it is possible to perform examination... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography But, other illumination methods can be used and, in some cases, may provide superior images with greater detail. Dark-field microscopy (DF), is an alternative method of observation that provides high-contrast images and actually greater resolution than bright-field. In dark-field illumination, the light f... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography Another useful imaging mode is differential interference contrast (DIC), which is usually obtained with a system designed by the Polish physicist Georges Nomarski. This system gives the best detail. DIC converts minor height differences on the plane-of-polish, invisible in BF, into visible detail. The det... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography When equipped with an energy dispersive spectrometer (EDS), the chemical composition of the microstructural features can be determined. The ability to detect low-atomic number elements, such as carbon, oxygen, and nitrogen, depends upon the nature of the detector used. But, quantification of these element... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography If a particular phase can be chemically extracted from a bulk specimen, it can be identified using XRD based on the crystal structure and lattice dimensions. This work can be complemented by EDS and/or WDS analysis where the chemical composition is quantified. But EDS and WDS are difficult to apply to par... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography These measurements may be made using manual procedures with the aid of templates overlaying the microstructure, or with automated image analyzers. In all cases, adequate sampling must be made to obtain a proper statistical basis for the measurement. Efforts to eliminate bias are required. Some of the most... | https://en.wikipedia.org/wiki?curid=2322835 |
Metallography A stereological method for characterizing discrete second-phase particles, such as nonmetallic inclusions, carbides, graphite, etc., is presented in ASTM E 1245. | https://en.wikipedia.org/wiki?curid=2322835 |
Nines (notation) Nines are an informal, logarithmic notation for proportions very near to one, or equivalently percentages very near 100%. Their common uses including grading the purity of materials. Put simply, "nines" are the number of consecutive nines in a percentage such as 99% (two nines) or a decimal fraction su... | https://en.wikipedia.org/wiki?curid=2322902 |
Nines (notation) The purity of a gas is generally expressed as a grade prefixed with the letter N giving the "number of nines" in the percentage or decimal fraction. For gasses, the number of nines is usually written after the letter N, rather than before it. An N2.0 gas is 99% pure, and 1% (by volume) impurities. An N... | https://en.wikipedia.org/wiki?curid=2322902 |
PyMOL is an open source molecular visualization system created by Warren Lyford DeLano. It was commercialized initially by DeLano Scientific LLC, which was a private software company dedicated to creating useful tools that become universally accessible to scientific and educational communities. It is currently commerci... | https://en.wikipedia.org/wiki?curid=2324407 |
PyMOL However, most of the current source code continues to be available for free, as are older precompiled builds. While the build systems for other platforms are open, the Windows API (WinAPI, Win32) build system is not, although unofficial Windows binaries are available online. Anyone can either compile an executabl... | https://en.wikipedia.org/wiki?curid=2324407 |
Metal foam A metal foam is a cellular structure consisting of a solid metal (frequently aluminium) with gas-filled pores comprising a large portion of the volume. The pores can be sealed (closed-cell foam) or interconnected (open-cell foam). The defining characteristic of metal foams is a high porosity: typically only ... | https://en.wikipedia.org/wiki?curid=2324595 |
Metal foam Metal sponge has very large surface area per unit weight and catalysts are often formed into metal sponge, such as palladium black, platinum sponge, and spongy nickel. Metals such as osmium and palladium hydride are metaphorically called "metal sponges", but this term is in reference to their property of bin... | https://en.wikipedia.org/wiki?curid=2324595 |
Metal foam They are light (typically 10–25% of the density of an identical non-porous alloy; commonly those of aluminium) and stiff and are frequently proposed as a lightweight structural material. However, they have not been widely used for this purpose. Closed-cell foams retain the fire resistance and recycling poten... | https://en.wikipedia.org/wiki?curid=2324595 |
Metal foam Production of precursors can be done by a combination of materials forming processes, such as powder pressing, extrusion (direct or conform) and flat rolling. Composite metal foam (CMF) is formed from hollow beads of one metal within a solid matrix of another, such as steel within aluminium, show 5 to 6 time... | https://en.wikipedia.org/wiki?curid=2324595 |
Metal foam A foam is said to be stochastic when the porosity distribution is random. Most foams are stochastic because of the method of manufacture: A foam is said to be regular when the structure is ordered. Direct molding is one technology that produces regular foams with open pores. Metal foams can also be produced ... | https://en.wikipedia.org/wiki?curid=2324595 |
Metal foam The primary functions of metallic foams in vehicles are to increase sound damping, reduce weight, increase energy absorption in case of crashes, and (in military applications) to combat the concussive force of IEDs. As an example, foam filled tubes could be used as anti-intrusion bars. Because of their low d... | https://en.wikipedia.org/wiki?curid=2324595 |
Metal foam For this application, metal foams are generally closed pore and made of aluminium. Foam panels are glued to the aluminium plate to obtain a resistant composite sandwich locally (in the sheet thickness) and rigid along the length depending on the foam's thickness. The advantage of metal foams is that the reac... | https://en.wikipedia.org/wiki?curid=2324595 |
Oddo–Harkins rule The holds that an element with an even atomic number (such as carbon: element 6) is more abundant than both elements with the adjacently larger and smaller odd atomic numbers (such as boron: element 5 and nitrogen: element 7, respectively, for carbon). This tendency of the abundance of the chemical el... | https://en.wikipedia.org/wiki?curid=2324648 |
Oddo–Harkins rule In this period, when inflation of the universe had brought it from an infinitesimal point to about the size of a modern galaxy, temperatures in the particle soup fell from over a trillion degrees to several million degrees. This period allowed for the fusion of single protons and deuterium nuclei to f... | https://en.wikipedia.org/wiki?curid=2324648 |
Oddo–Harkins rule When fusion occurs with larger and larger nuclei, the energy input becomes increasingly larger and the energy output becomes increasingly smaller; the point at which these two potentials meet on the periodic table of elements is somewhere around the elements iron, atomic number 26, and nickel, atomic ... | https://en.wikipedia.org/wiki?curid=2324648 |
Impact (mechanics) In mechanics, an impact is a high force or shock applied over a short time period when two or more bodies collide. Such a force or acceleration usually has a greater effect than a lower force applied over a proportionally longer period. The effect depends critically on the relative velocity of the bo... | https://en.wikipedia.org/wiki?curid=2325044 |
Impact (mechanics) Different materials can behave in quite different ways in impact when compared with static loading conditions. Ductile materials like steel tend to become more brittle at high loading rates, and spalling may occur on the reverse side to the impact if penetration doesn't occur. The way in which the ki... | https://en.wikipedia.org/wiki?curid=2325044 |
Impact (mechanics) That is, it fractures, and does not stretch or vibrate. Road traffic accidents usually involve impact loading, such as when a car hits a traffic bollard, water hydrant or tree, the damage being localized to the impact zone. When vehicles collide, the damage increases with the relative velocity of the... | https://en.wikipedia.org/wiki?curid=2325044 |
Impact (mechanics) When fragile items are shipped, impacts and drops can cause product damage. Protective packaging and cushioning help reduce the peak acceleration by extending the duration of the shock or impact. | https://en.wikipedia.org/wiki?curid=2325044 |
Mulliken population analysis Mulliken charges arise from the and provide a means of estimating partial atomic charges from calculations carried out by the methods of computational chemistry, particularly those based on the linear combination of atomic orbitals molecular orbital method, and are routinely used as variabl... | https://en.wikipedia.org/wiki?curid=2327478 |
Mulliken population analysis In a modified Mulliken population analysis, this problem can be reduced by dividing the overlap populations formula_15 between the corresponding orbital populations formula_16 and formula_17 in the ratio between the latter. This choice, although still arbitrary, relates the partitioning in ... | https://en.wikipedia.org/wiki?curid=2327478 |
Proton-exchange membrane A proton-exchange membrane, or polymer-electrolyte membrane (PEM), is a semipermeable membrane generally made from ionomers and designed to conduct protons while acting as an electronic insulator and reactant barrier, e.g. to oxygen and hydrogen gas. This is their essential function when incorp... | https://en.wikipedia.org/wiki?curid=2328120 |
Proton-exchange membrane PEMFCs operate at 40–60% efficiency and can vary the output to match the demands. First used in the 1960s for the NASA Gemini program, PEMFCs are currently being developed and demonstrated from ~100 kW cars to a 59 MW power plant. PEMFCs have some advantages over other types of fuel cells such ... | https://en.wikipedia.org/wiki?curid=2328120 |
Proton-exchange membrane As a result, new anhydrous proton conductors, such as protic organic ionic plastic crystals (POIPCs) and protic ionic liquids, are actively studied for the development of suitable PEMs. The fuel for the PEMFC is hydrogen, and the charge carrier is the hydrogen ion (proton). At the anode, the hy... | https://en.wikipedia.org/wiki?curid=2328120 |
Noncovalent solid-phase organic synthesis or NC-SPOS is a form of Solid-phase synthesis whereby the organic substrate is bonded to the solid phase not by a covalent bond but by other chemical interactions. This bond may consist of an induced dipole interaction between a hydrophobic matrix and a hydrophobic anchor. As l... | https://en.wikipedia.org/wiki?curid=2329092 |
Phosphate-buffered saline (abbreviated PBS) is a buffer solution commonly used in biological research. It is a water-based salt solution containing disodium hydrogen phosphate, sodium chloride and, in some formulations, potassium chloride and potassium dihydrogen phosphate. The buffer helps to maintain a constant pH. T... | https://en.wikipedia.org/wiki?curid=2330489 |
Phosphate-buffered saline The pH of PBS is ~7.4. When making buffer solutions, it is good practice to always measure the pH directly using a pH meter. If necessary, pH can be adjusted using hydrochloric acid or sodium hydroxide. PBS can also be prepared by using commercially made PBS buffer tablets or pouches. If used ... | https://en.wikipedia.org/wiki?curid=2330489 |
Molecular memory is a term for data storage technologies that use molecular species as the data storage element, rather than e.g. circuits, magnetics, inorganic materials or physical shapes. The molecular component can be described as a molecular switch, and may perform this function by any of several mechanisms, inclu... | https://en.wikipedia.org/wiki?curid=2331095 |
Molecular memory Several universities and a number of companies (Hewlett Packard, ZettaCore) have announced work on molecular memories, which some hope will supplant DRAM memory as the lowest cost technology for high-speed computer memory. NASA is also supporting research on non-volatile molecular memories. In 2018, re... | https://en.wikipedia.org/wiki?curid=2331095 |
Critical radius is the minimum size that must be formed by atoms or molecules clustering together (in a gas, liquid or solid matrix) before a new-phase inclusion (a bubble, a droplet, or a solid particle) is stable and begins to grow. Formation of such stable "nuclei" is called nucleation. In precipitation models this ... | https://en.wikipedia.org/wiki?curid=2331297 |
Hydroboration In chemistry, hydroboration refers to the addition of a hydrogen-boron bond to C-C, C-N, and C-O double bonds, as well as C-C triple bonds. This chemical reaction is useful in the organic synthesis of organic compounds. The development of this technology and the underlying concepts were recognized by the ... | https://en.wikipedia.org/wiki?curid=2331525 |
Hydroboration As a result, in the transition state, boron develops a partially negative charge while the more substituted carbon bears a partially positive charge. This partial positive charge is better supported by the more substituted carbon. Formally, the reaction is an example of a group transfer reaction. However,... | https://en.wikipedia.org/wiki?curid=2331525 |
Hydroboration For such 1,2-disubstituted olefins, regioselectivity can be observed only when one of the two substituents is a phenyl ring. In such cases, such as "trans"-1-phenylpropene, the boron atom is placed on the carbon adjacent to the phenyl ring. The observations above indicate that the addition of H-B bond to ... | https://en.wikipedia.org/wiki?curid=2331525 |
Hydroboration The adduct BH(THF) is also commercially available as THF solutions wherein it exists as the 1:1 adduct. It degrades with time. Borane adducts with phosphines and amines are also available, but are not widely used. Borane makes a strong adduct with triethylamine; using this adduct requires harsher conditio... | https://en.wikipedia.org/wiki?curid=2331525 |
Hydroboration Among hindered dialkylboranes, disiamylborane (abbreviated SiaBH, but is a dimer [SiaBH]) is well known for selective hydroboration of less hindered, usually terminal alkenes in the presence of more substituted alkenes. Disiamylborane must be freshly prepared as its solutions can only be stored at 0 °C fo... | https://en.wikipedia.org/wiki?curid=2331525 |
Hydroboration They also exhibit higher reactivity toward alkynes. Pinacolborane is also widely used in a catalyst-free hydroborations. | https://en.wikipedia.org/wiki?curid=2331525 |
Time-dependent density functional theory Time-dependent density-functional theory (TDDFT) is a quantum mechanical theory used in physics and chemistry to investigate the properties and dynamics of many-body systems in the presence of time-dependent potentials, such as electric or magnetic fields. The effect of such fie... | https://en.wikipedia.org/wiki?curid=2331527 |
Time-dependent density functional theory This implies that the many-body wavefunction, depending upon 3"N" variables, is equivalent to the density, which depends upon only 3, and that all properties of a system can thus be determined from knowledge of the density alone. Unlike in DFT, there is no general minimization p... | https://en.wikipedia.org/wiki?curid=2331527 |
Time-dependent density functional theory The approach of Runge and Gross considers a single-component system in the presence of a time-dependent scalar field for which the Hamiltonian takes the form where "T" is the kinetic energy operator, "W" the electron-electron interaction, and "V"("t") the external potential whic... | https://en.wikipedia.org/wiki?curid=2331527 |
Time-dependent density functional theory The advantage of doing so lies in the ease in which non-interacting systems can be solved – the wave function of a non-interacting system can be represented as a Slater determinant of single-particle orbitals, each of which are determined by a single partial differential equatio... | https://en.wikipedia.org/wiki?curid=2331527 |
Time-dependent density functional theory The remaining component is the exchange-correlation potential: In their seminal paper, Runge and Gross approached the definition of the KS potential through an action-based argument starting from the Dirac action Treated as a functional of the wave function, "A"[Ψ], variations o... | https://en.wikipedia.org/wiki?curid=2331527 |
Time-dependent density functional theory Linear-response TDDFT can be used if the external perturbation is small in the sense that it does not completely destroy the ground-state structure of the system. In this case one can analyze the linear response of the system. This is a great advantage as, to first order, the va... | https://en.wikipedia.org/wiki?curid=2331527 |
Naphthol may refer to: | https://en.wikipedia.org/wiki?curid=2331700 |
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