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Poly(amidoamine) When the charge balance between DNA phosphates and PAMAM surface amines is slightly positive, the maximum transfection efficiency is obtained; this finding supports the idea that the complex binds to the cell surface via charge interactions. A striking observation is that "activation" of PAMAM by parti... | https://en.wikipedia.org/wiki?curid=41237117 |
Poly(amidoamine) Dendrimer release and swelling can eventually lyse the endosome, resulting in release of the cargo DNA. The activated PAMAM dendrimers have less spatial barrier to interior amine protonation, which is thought to be a major source of their advantage over non-activated PAMAM. In the context of existing a... | https://en.wikipedia.org/wiki?curid=41237117 |
Poly(amidoamine) Since PAMAM dendrimers and their complexes with DNA exhibit low cytotoxicity, higher transfection efficiencies than liposome-based methods, and are effective across a broad range of cell lines, they have taken an important place in modern gene therapy methodologies. The biotechnology company Qiagen cur... | https://en.wikipedia.org/wiki?curid=41237117 |
C9H16 The molecular formula CH may refer to: | https://en.wikipedia.org/wiki?curid=41239359 |
C16H28O2 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=41239392 |
Morse/Long-range potential The (MLR potential) is a interatomic interaction model for the potential energy of a diatomic molecule. Due to the simplicity of the regular Morse potential (it only has three adjustable parameters), it is not used in modern spectroscopy. The MLR potential is a modern version of the Morse pot... | https://en.wikipedia.org/wiki?curid=41240510 |
Morse/Long-range potential A further extension of the MLR potential referred to as the MLR3 potential was introduced in a 2010 study of Cs, and this potential has since been used on HF, HCl, HBr and HI. The energy function is of the form where for large formula_2, so formula_4 is defined according to the theoretically ... | https://en.wikipedia.org/wiki?curid=41240510 |
Morse/Long-range potential It has also become customary to fit ab initio points to the MLR potential, to achieve a fully analytic ab initio potential and to take advantage of the MLR's ability to incorporate the correct theoretically known short- and long-range behavior into the potential (the latter usually being of h... | https://en.wikipedia.org/wiki?curid=41240510 |
Small stationary reformer A small stationary reformer is an on-site device used for the production of hydrogen from hydrocarbons on a small scale. A membrane reactor is a device where oxygen separation, steam reforming and POX is combined in a single step. In 1997 Argonne National Laboratory and Amoco published a paper... | https://en.wikipedia.org/wiki?curid=41241518 |
Dynamic kinetic resolution in asymmetric synthesis Dynamic kinetic resolution in chemistry is a type of kinetic resolution where 100% of a racemic compound can be converted into an enantiopure compound. It is applied in asymmetric synthesis. Asymmetric synthesis has become a much explored field due to the challenge of ... | https://en.wikipedia.org/wiki?curid=41242993 |
Dynamic kinetic resolution in asymmetric synthesis The presence of an acidic center between two carbonyl groups allows for easy epimerization at the chiral center under basic conditions. To select for one of the four possible stereoisomers, a BINAP-Ru catalyst is used to control the outcome of the reaction through the ... | https://en.wikipedia.org/wiki?curid=41242993 |
Dynamic kinetic resolution in asymmetric synthesis Copper proved to be an excellent metal in this reaction due to its ability to complex with the oxygen when the hydrogen was added. Being a soft metal, copper greatly prefers 1,4 addition over 1,2 addition, with the alkene being a softer more polarizable electrophile. A... | https://en.wikipedia.org/wiki?curid=41242993 |
Dynamic kinetic resolution in asymmetric synthesis The selectivity for this product can best be explained by the Felkin model. The cyclic (E)-enamine is able to undergo a favorable transition state where the aldehyde adopts an anti relationship relative to the incoming nucleophile, as well as a 1,2 syn relationship bet... | https://en.wikipedia.org/wiki?curid=41242993 |
Dynamic kinetic resolution in asymmetric synthesis The addition of CALB catalyzes the reaction between the (R) isomer and the ester reagent to form a product with a diene and a dienophile. This intermediate can then undergo a tandem Diels-Alder reaction to achieve a decent yield with 97% ee. Dynamic kinetic resolution ... | https://en.wikipedia.org/wiki?curid=41242993 |
Dynamic kinetic resolution in asymmetric synthesis As the scope and application of this powerful concept increases, its utilization in the industrial and academic settings is likely to expand in the years to come. | https://en.wikipedia.org/wiki?curid=41242993 |
Miracle of the cruse of oil () is an Aggadah depicted in the Babylonian Talmud as one of the reasons for Hanukkah. The story of the miracle, as described in the Talmud, occurred after the liberation of the Temple in Jerusalem during the Maccabean Revolt, and describes how the finding of a jug of pure oil that was to be... | https://en.wikipedia.org/wiki?curid=41249743 |
Miracle of the cruse of oil Miraculously, the one cruse of oil lasted eight nights. The Torah discusses the lighting of the Temple menorah in a number of verses. specifies that pure olive oil must be used to light the menorah. While and speak of seven lights being lit, and specifies that a single "light" must be lit "c... | https://en.wikipedia.org/wiki?curid=41249743 |
Miracle of the cruse of oil Since the process of ritual purification after touching a corpse lasts seven days, the Maccabees could only produce additional pure oil after eight days: seven days of becoming pure including one day, once pure, to actually make the oil. Therefore, the Maccabees would have been unable to lig... | https://en.wikipedia.org/wiki?curid=41249743 |
Miracle of the cruse of oil While lighting the Menorah on Hanukkah was originally established solely to commemorate the miracle of the cruse oil, after the destruction of the Second Temple, the holiday took on an additional role. It now also serves as a commemoration of the daily lighting of the Menorah in the Temple, ... | https://en.wikipedia.org/wiki?curid=41249743 |
Operation Shocker was a 23-year counterintelligence operation run by the US Federal Bureau of Investigation against the Soviet Union. The operation involved the fake defection in place of a US Army sergeant based in Washington, D.C. who, in return for hundreds of thousands of dollars over two decades, provided informat... | https://en.wikipedia.org/wiki?curid=41254380 |
Operation Shocker Cassidy provided over 4,000 documents on a mixture of real and non-existent research into the new gas, with the US intending to waste Soviet resources attempting to duplicate the work. David Wise, in his book "Cassidy's Run", implies that the Soviet program to develop the Novichok agents may have been... | https://en.wikipedia.org/wiki?curid=41254380 |
Andreas Hierlemann (17 August 1964) is a German chemist and professor of Biosystems Engineering at ETH Zurich. He is known for his work in the field of CMOS-based chemical and biomicrosensors and high-density microelectrode arrays. From 1985-91 Hierlemann studied chemistry at the University of Tübingen, Germany. He rec... | https://en.wikipedia.org/wiki?curid=41257069 |
Andreas Hierlemann It includes the development of CMOS-based integrated chemical and biomicrosystems, as well as bioelectronics and high-density microelectrode arrays. The high-density microelectrode arrays are used for fundamental research in information processing and signaling characteristics of neurons or brain cel... | https://en.wikipedia.org/wiki?curid=41257069 |
Elasto-capillarity is the ability of capillary force to deform an elastic material. From the viewpoint of mechanics, elastocapillarity phenomena essentially involve competition between the elastic strain energy in the bulk and the energy on the surfaces/interfaces. In the modeling of these phenomena, some challenging i... | https://en.wikipedia.org/wiki?curid=41264425 |
Elasto-capillarity However, if a water is deposited on the PDMS (formula_10 ~ 300 kPa), this caused the deformation to be formula_9 ~10m, which is in micron scale, this can have great impact on the micro/nanotechnology applications where length scale is comparable and "soft" photoresists were used. The elasto-capillary... | https://en.wikipedia.org/wiki?curid=41264425 |
Elasto-capillarity By balancing gain of surface energy by capillary force and loss of elastic energy by banding a flexible sheet and minimizing with respect to L, dry length was found to be: formula_13 Where formula_12 is the elastocapillary length of sheets w is the distance between two parallel sheets This L sets the... | https://en.wikipedia.org/wiki?curid=41264425 |
Elasto-capillarity the pressure inside liquid is less than the ambient pressure, and if the liquid doesn't wet the contacting surfaces then the pressure difference is positive and liquid pressure is higher than the ambient pressure. The coalescence happens in a brush after removing it from water is an example of elasto... | https://en.wikipedia.org/wiki?curid=41264425 |
Elasto-capillarity where: These tensile stresses put the two surfaces into more contact while the compressive stresses due to the elastic deformation of the surfaces tend to resist them. Two scenarios could happen in this case: 1. The tensile and compressive stresses come into balance which in this case the gap between... | https://en.wikipedia.org/wiki?curid=41264425 |
Process chemistry is the arm of pharmaceutical chemistry concerned with the development and optimization of a synthetic scheme and pilot plant procedure to manufacture compounds for the drug development phase. is distinguished from medicinal chemistry, which is the arm of pharmaceutical chemistry tasked with designing ... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Additionally, the many complex factors associated with chemical plant engineering (for example, heat transfer and reactor design) and drug formulation will be treated cursorily. Cost efficiency is of paramount importance in process chemistry and, consequently, is a focus in the consideration of pilot ... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry The conversion cost of a chemical process is a factor of that procedure's overall efficiency, both in materials and time, and its reproducibility. The efficiency of a chemical process can be quantified by its atom economy, yield, volume-time output, and environmental factor (E-factor), and its reprodu... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Yield is defined as the amount of product obtained in a chemical reaction the yield of practical significance in process chemistry is the isolated yield—the yield of the isolated product after all purification steps. In a final API synthesis, isolated yields of 80 percent or above for each synthetic s... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Finally, to minimize overall cost, synthetic steps involving expensive reagents, solvents or catalysts should be designed into the process route as late stage as possible, to minimize the amount of reagent used. In a pilot plant or manufacturing plant setting, yield can have a profound effect on the m... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Additionally, the raw conversion cost of an API synthesis (in dollars per batch) can be calculated from the VTO, given the operating cost and usable capacity of a particular reactor. Oftentimes, for large-volume APIs, it is economical to build a dedicated production plant rather than to use space in g... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry A reasonable target for the E-factor or PMI of a single synthetic step is any value between 10 and 40. The final two "conversion cost" considerations involve the reproducibility of a given reaction or API synthesis route. The quality service level (QSL) is a measure of the reproducibility of the quali... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry For example, if an isolation step is particularly difficult or slow, it could become the bottleneck for an API synthesis, in which case the reproducibility and optimization of that operation become critical. For an API manufacturing process, all PEI metrics (yield and cycle times) should be targeted a... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Two significant shortcomings were immediately identified with the initial scale-up route to BILN 2061, depicted in the scheme below. The macrocyclization step posed four challenges inherent to the cross-metathesis reaction. Additionally, the final double S2 sequence to install the quinoline heterocycl... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry This modification prevented the need for inefficient double inversion by proceeding through retention of stereochemistry at the C-4 position of the hydroxyproline moiety. It is interesting to examine this case study from a VTO perspective. For the unoptimized cross-metathesis reaction using the Grela ... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Many varied classes of naturally occurring enzymes have been co-opted and engineered for process pharmaceutical chemistry applications. The widest range of applications come from ketoreductases and transaminases, but there are isolated examples from hydrolases, aldolases, oxidative enzymes, esterases ... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry Additionally, the enzyme was engineered to handle high substrate concentrations (100 g/L) and to tolerate the organic solvents, reagents and byproducts of the transamination reaction. This biocatalytic route successfully avoided the limitations of the chemocatalyzed hydrogenation route: the requiremen... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry A case study of particular interest involves the development of a fully continuous process by the process chemistry group at Eli Lilly and Company for an asymmetric hydrogenation to access a key intermediate in the synthesis of LY500307, a potent ERβ agonist that is entering clinical trials for the tr... | https://en.wikipedia.org/wiki?curid=41264758 |
Process chemistry The process chemistry team at Eli Lilly successfully developed a fully continuous process to this penultimate intermediate, including reaction, workup and kinetically controlled crystallization modules (the engineering considerations implicit in these efforts are beyond the scope of this article). An ... | https://en.wikipedia.org/wiki?curid=41264758 |
Supramolecular catalysis is not a well-defined field but it generally refers to an application of supramolecular chemistry, especially molecular recognition and guest binding, toward catalysis. This field was originally inspired by enzymatic system which, unlike classical organic chemistry reactions, utilizes non-coval... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis The term supramolecular chemistry is defined by Jean-Marie Lehn as "the chemistry of intermolecular bond, covering structures and functions of the entities formed by association of two or more chemical species" in his Nobel lecture in 1987, but the concept of supramolecular catalysis was starte... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis developed a catalyst based on a beta-cyclodextrin carrying two imidazole groups. This cyclodextrin catalytic system mimics ribonuclease A by its use of a neutral imidazole and an imidazolium cation to selective cleave cyclic phosphate substrates. The rate of the reaction is catalyzed 120 times ... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis This concept is similar to the principle of preorganization which states that complexation could be improved if the binding motifs are preorganized in a well-defined position so that the host does not require any major conformational change for complexation. In this case, the catalyst is preorg... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis Examples of molecules that work via this mechanism are Rebek's tennis ball and Fujita's octahedral complex. Supramolecular catalysts can accelerate reactions not only by placing the two reactants in close proximity but also by stabilizing the transition state of the reaction and reducing activa... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis These catalysts are often inspired by the structure of enzymes with the catalytic group mimicking reactive amino acid residues, but unlike real enzymes, the binding sites of these catalysts are rigid structure made from chemical building blocks. All of the examples in this article are developed... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis This computational method starts simply with a predicted transition state structure and slowly builds outward by optimizing the arrangement of functional groups to stabilize the transition state. Then it fills out the remainder of the active site and, finally, it generates an entire protein sca... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis TSAs do not necessarily represent real transition states and so a catalyst obtained from screening could just be the best receptor for a TSA but is not necessarily the best catalyst. To circumvent this problem, catalytic activity needs to be measured directly and also quickly. To develop a high... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis used this method to create a dynamic combinatorial library of imine inhibitor from a set of amines and a set of aldehydes. After some time, the equilibrium was terminated by an addition of NaBHCN to afford the desired catalyst. In nature, pyruvate oxidase employs two cofactors thiamine pyrophos... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis Nolte and coworkers developed an artificial processive enzyme in a form of manganese porphyrin rotaxane that treads along a long polymer of alkene and catalyze multiple rounds of alkene epoxidation. Manganese (III) ion in the porphyrin is the molecule's catalytic center, capable of epoxidation ... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis Unfortunately, this catalyst has a problem with product inhibition. To by pass that problem, the product of the cyclization reaction could be reacted with a dienophile transforming it into a Diels-Alder adduct that no longer fits inside the catalyst cavity. In this case, the supramolecular host... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis Within the chiral microenvironment, the catalysts has a geometrically fixed bifunctional active site that activates both an electrophilic part and a nucleophilic part of a substrate. This catalyst enables stereoselective spiroacetal formation with high enantiomeric excess for a variety of subst... | https://en.wikipedia.org/wiki?curid=41267493 |
Supramolecular catalysis In many supramolecular catalytic systems designed to work with bimolecular addition reactions like the Diels-Alder, the product of the reaction binds more strongly to the supramolecular host than the two substrates do, consequently leading to inhibition by the product. As a result, these cataly... | https://en.wikipedia.org/wiki?curid=41267493 |
C20H24N2O The molecular formula CHNO may refer to: | https://en.wikipedia.org/wiki?curid=41267684 |
Broadband acoustic resonance dissolution spectroscopy (also known as BARDS) is a technique developed in the late 2000s, which is used in analytical chemistry. It involves the analysis of the changes in sound frequency generated when a solute dissolves in a solvent, by harnessing the hot chocolate effect first described... | https://en.wikipedia.org/wiki?curid=41270451 |
Broadband acoustic resonance dissolution spectroscopy Crawford derived the relationship between fractional bubble volume and sound velocity in water, and hence the sound frequency in water, given as. where "υ" and "υ" are the velocities of sound in pure and bubble-filled water, respectively, "f" and "f" are the frequen... | https://en.wikipedia.org/wiki?curid=41270451 |
David Guy David Wade Guy (1897-1960) was an American military aviator. Guy flew biplanes for both France's Aeronautique Militaire and the U.S. Army Air Service during World War I. He served in the Lafayette Flying Corps, a group of 180 American pilots who flew for France. Guy was born in St. Louis, Missouri, to William... | https://en.wikipedia.org/wiki?curid=41274332 |
David Guy Guy also served in the AFS unit that carried the American flag to the front. After his AFS service, he joined France's Aeronautique Militaire on July 21, 1917. Guy studied at several French flying schools between August and November; he attended flying schools in Tours, Avord, Pau, and G.D.E. He then began se... | https://en.wikipedia.org/wiki?curid=41274332 |
David Guy Following the end of the war, Guy resumed his college studies at the Massachusetts Institute of Technology in Cambridge, MA. He received his bachelor's degree in chemical engineering in 1922. Following graduation, Guy worked for Monsanto Company, a chemical company in Missouri, and then Ingersoll Rand, an Iri... | https://en.wikipedia.org/wiki?curid=41274332 |
Ante Graovac is a Croatian scientist (born July 15, 1945 in Split, died November 13, 2012 in Zagreb) known for his contribution to chemical graph theory. He was director of 26 successful annual meetings MATH/CHEM/COMP held in Dubrovnik. He was Secretary of the International Academy of Mathematical Chemistry. | https://en.wikipedia.org/wiki?curid=41275177 |
Photoredox catalysis is a branch of catalysis that harnesses the energy of light to accelerate a chemical reaction via single-electron transfer events. This area is named as a combination of "photo-" referring to light and redox, a condensed expression for the chemical processes of reduction and oxidation. In particula... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis is often applied to generate known reactive intermediates in a novel way and has led to the discovery of new organic reactions, such as the first direct functionalization of the β-arylation of saturated aldehydes. While the D-symmetric transition-metal complexes used in many photoredox-catalyzed re... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis This singlet excited state can relax further by two distinct processes: the catalyst may fluoresce, radiating a photon and returning to the singlet ground state, or it can move to the lowest energy triplet excited state (a state where two unpaired electrons have the same spin) by a second non-radia... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis between strong reductants and oxidants) and where the electron transfer has a low intrinsic barrier. The intrinsic barrier of electron transfer derives from the Franck–Condon principle, stating that electronic transition takes place more quickly given greater overlap between the initial and final e... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis Since electron transfer of these complexes is fast, it is likely to take place within the duration of the catalyst's active state, i.e. during the lifetime of the triplet excited state. The final step in the photocatalytic cycle is the regeneration of the photocatalyst in its ground state. At this ... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis The Stern–Volmer experiment measures the intensity of phosphorescence while varying the concentration of each possible quenching agent. When the concentration of the actual quenching agent is varied, the rate of electron transfer and the degree of phosphorescence is affected. This relationship is m... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis To estimate the excited-state redox potentials, one method is to compare the rates of electron transfer from the excited state to a series of ground-state reactants whose redox potentials are known. A more common method to estimate these potentials is to use an equation developed by Rehm and Weller... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis In fact, the concentration of excited-state species in the cell should change exactly in phase with the intensity of light incident on the electrochemical cell. If the potential applied to the cell is strong enough for electron transfer to occur, the change in concentration of the redox-competent e... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis Since the remainder of the ligand molecule is identical and phenylpyridine holds electrons less tightly than bipyridine, it is more strongly electron-donating and less electronegative as a ligand. Hence, complexes with phenylpyridine ligands are more strongly reducing and less strongly oxidizing th... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis In effect, while ground-state ruthenium complexes can be potent reductants, the excited-state complex is a far less potent reductant or oxidant than its equivalent iridium complex. This makes iridium preferred for the development of general organic transformations because the stronger redox potenti... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis The stoichiometric reductant present in this reaction transfers an electron to reduce the excited-state catalyst to the Ru(I) oxidation state. The reduced catalyst then shuttles the transferred electron to the halogenated substrate, reducing the weak C-X bond and inducing fragmentation. Unactivated... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis However, the condensation of amines with carbonyl compounds to form iminium ions is often unfavorable, sometimes requiring harsh dehydrating conditions. Thus, alternative methods for iminium ion generation, particularly by oxidation from the corresponding amine, are a valuable synthesis tool. Imini... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis The development of orthogonal protecting groups is a problem in organic synthesis because these protecting groups allow each instance of a common functional group, such as the hydroxyl group, to be distinguished during the synthesis of a complex molecule. A very common protecting group for the hydr... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis After the arene is oxidized, it will readily participate in hydrogen atom transfer with trichloromethyl radical to form chloroform and an oxocarbenium ion, which is readily hydrolyzed to reveal the free hydroxide. This reaction was demonstrated to be orthogonal to many common protecting groups when... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis Yoon demonstrated the efficient intra- and intermolecular [2+2] cycloadditions of activated olefins: particularly enones and styrenes. Enones, or electron-poor olefins, were discovered to react via a radical-anion pathway, utilizing diisopropylethylamine as a transient source of electrons. For this... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis This comparison of photocatalysts highlights the importance of tuning the redox properties of a photocatalyst to the reaction system as well as demonstrating the value of polypyridyl compounds as ligands, due to the ease with which they can be modified to adjust the redox properties of their comple... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis The photoredox case, since it takes place by a different mechanism than the thermal Diels–Alder reaction, allows cycloaddition between an electron-rich diene and an electron-rich dienophile, allowing access to new classes of Diels–Alder adducts. The synthetic value of Yoon's photoredox-catalyzed st... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis In this approach for the α-alkylation of aldehydes, [Ru(bipy)] reductively fragments an activated alkyl halide, such as bromomalonate or phenacyl bromide, which can then add to catalytically-generated enamine in an enantioselective manner. The oxidized photocatalyst then oxidatively quenches the re... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis also investigated the productive merger of photoredox and organocatalytic methods to achieve enantioselective alkylation of aldehydes. The same chiral imidazolidinone organocatalyst was used to form enamine and introduce chirality. However, the organic photoredox catalyst Eosin Y was used rather th... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis The resulting enamine radical cation usually reacts as a 3 π-electron system, but due to the stability of the radical coupling partners, deprotonation of the β-methylene position gives rise to a 5 π-electron system with strong radical character at the newly accessed β-carbon. Although this reaction... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis [Ru(bipy)] was found to catalyze the fragmentation of tosylphenylselenide to phenylselenolate anion and tosyl radical and that a radical chain propagation mechanism allowed the addition of tosyl radical and phenylseleno- radical across the double bond of electron rich alkyl vinyl ethers. Since phen... | https://en.wikipedia.org/wiki?curid=41278027 |
Photoredox catalysis Hydrotrifluoromethylation of styrenes and aliphatic alkenes can be effected with a mesityl acridinium organic photoredox catalyst and Langlois' reagent as the source of CF radical. In this reaction, it was found that trifluoroethanol and substoichiometric amounts of an aromatic thiol, such as methy... | https://en.wikipedia.org/wiki?curid=41278027 |
Drop impact occurs when a liquid drop strikes a solid or liquid surface. The resulting outcome depends on the properties of the drop, the surface, and the surrounding fluid, which is most commonly a gas. When a liquid drop strikes a dry solid surface, it generally spreads on the surface, and then will retract if the im... | https://en.wikipedia.org/wiki?curid=41280949 |
Drop impact The contact time is independent of velocity in this regime. The minimum contact time for a low deformation drop (We « 1) is approximated by the lowest-order oscillation period for a spherical drop., giving the characteristic time a prefactor of approximately 2.2. For large-deformation drops (We > 1), simila... | https://en.wikipedia.org/wiki?curid=41280949 |
Drop impact In the case of floating, a drop will float on the surface for several seconds. Cleanliness of the liquid surface is reportedly very important in the ability of drops to float. Drop bouncing can occur on perturbed liquid surfaces. If the drop is able to rupture a thin film of gas separating it from the liqui... | https://en.wikipedia.org/wiki?curid=41280949 |
Strontian process The strontian process is an obsolete chemical method to recover sugar from molasses. Its use in Europe peaked in the middle of the 19th century. The name "strontian" comes from the Scottish village Strontian where the source mineral strontianite (strontium carbonate) was first found. Strontium carbona... | https://en.wikipedia.org/wiki?curid=41281214 |
Strontian process One of the biggest mines, at Drensteinfurt, was named after Dr. Reichardt, the director of the Dessauer Sugar Refinery. A further place the strontian process came to be used was the Sugar Factory Rositz (in Rositz). Yet by 1883, the demand on strontianite had begun to shrink. Firstly, it was replaced ... | https://en.wikipedia.org/wiki?curid=41281214 |
Flow cytometry bioinformatics is the application of bioinformatics to flow cytometry data, which involves storing, retrieving, organizing and analyzing flow cytometry data using extensive computational resources and tools. requires extensive use of and contributes to the development of techniques from computational sta... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics It is also possible to characterize data in more comprehensive ways, such as the density-guided binary space partitioning technique known as probability binning, or by combinatorial gating. Finally, diagnosis using flow cytometry data can be aided by supervised learning techniques, and dis... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics The stream is interrogated by one or more lasers, and the resulting fluorescent and scattered light is detected by photomultipliers. By using optical filters, particular fluorophores on or within the cells can be quantified by peaks in their emission spectra. These may be endogenous fluoro... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics The rapid increase in the dimensionality of flow cytometry data, coupled with the development of high-throughput robotic platforms capable of assaying hundreds to thousands of samples automatically have created a need for improved computational analysis methods. Flow cytometry data is in t... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics An attempt to solve this problem is the development of the Gating-ML XML-based data standard (discussed in more detail under the standards section), which is slowly being adopted in both commercial and open source flow cytometry software. The CytoML R package is also filling the gap by imp... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics The total signal to remove from each channel can be computed by solving a system of linear equations based on this data to produce a spillover matrix, which when inverted and multiplied with the raw data from the cytometer produces the compensated data. The processes of computing the spill... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics However, a later comparison of the flowTrans package used in that comparison indicated that it did not parameterize the Logicle transformation in a manner consistent with other implementations, potentially calling those results into question. Particularly in newer, high-throughput experime... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics However, this is the combination of technical variations introduced by the instruments and handling, and actual biological information that is desired to be measured. Disambiguating the technical and the biological contributions to between-sample variation can be a difficult to impossible ... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics The regions on these plots can be sequentially separated, based on fluorescence intensity, by creating a series of subset extractions, termed "gates". These gates can be produced using software, e.g. Flowjo, FCS Express, WinMDI, CytoPaint (aka Paint-A-Gate), VenturiOne, Cellcion, CellQuest... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics To address this issue, principal component analysis has been used to summarize the high-dimensional datasets using a combination of markers that maximizes the variance of all data points. However, PCA is a linear method and is not able to preserve complex and non-linear relationships. More... | https://en.wikipedia.org/wiki?curid=41282920 |
Flow cytometry bioinformatics The FlowCAP (Flow Cytometry: Critical Assessment of Population Identification Methods) project, with active participation from most academic groups with research efforts in the area, is providing a way to objectively cross-compare state-of-the-art automated analysis approaches. Other surve... | https://en.wikipedia.org/wiki?curid=41282920 |
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