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91.
Gunawan Gunawan Tito Viswanathan Shawn Bourdo Alexandru S. Biris 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):768-777
Abstract A novel, fast, and easy method for synthesizing a carbon-supported Ni2P nanocomposite (C/Ni2P) is described. The process involves a reaction between a nickel salt, phosphoric acid, and a carbon source by utilizing microwave irradiation. The carbon source for the nanocomposite is from renewable supplies, namely, tannin and lignin. The method has successfully synthesized Ni2P nanoparticles dispersed in a carbon matrix with a particle size ranging from 20 to 50 nm in diameter. During the microwave process, tannin and lignin provided a reducing environment in the microwave irradiation process. The synthesized products are characterized by several characterization methods. The method showed that phosphoric acid, which is a nontoxic compound, could be used as an alternative P source for synthesizing Ni2P. The method is fast, easy, and an economical process to synthesize the carbon-coated Ni2P nanocomposite. 相似文献
92.
Livia Salvati Manni Dr. Alexandru Zabara Dr. Yazmin M. Osornio Jendrik Schöppe Dr. Alexander Batyuk Prof. Dr. Andreas Plückthun Prof. Dr. Jay S. Siegel Prof. Dr. Raffaele Mezzenga Prof. Dr. Ehud M. Landau 《Angewandte Chemie (International ed. in English)》2015,54(3):1027-1031
Lipidic cubic phases (LCPs) are used in areas ranging from membrane biology to biodevices. Because some membrane proteins are notoriously unstable at room temperature, and available LCPs undergo transformation to lamellar phases at low temperatures, development of stable low‐temperature LCPs for biophysical studies of membrane proteins is called for. Monodihydrosterculin (MDS) is a designer lipid based on monoolein (MO) with a configurationally restricted cyclopropyl ring replacing the olefin. Small‐angle X‐ray scattering (SAXS) analyses revealed a phase diagram for MDS lacking the high‐temperature, highly curved reverse hexagonal phase typical for MO, and extending the cubic phase boundary to lower temperature, thereby establishing the relationship between lipid molecular structure and mesophase behavior. The use of MDS as a new material for LCP‐based membrane protein crystallization at low temperature was demonstrated by crystallizing bacteriorhodopsin at 20 °C as well as 4 °C. 相似文献
93.
Pavel F. Vlad Alexandru G. Ciocarlan Mihai N. Coltsa Alexandr V. Baranovsky Natalya B. Khripach 《合成通讯》2013,43(22):3960-3972
This article describes a new efficient synthesis of drim-7,9(11)-diene and its hydroxylated derivates from drim-8-en-7-one. Reduction of this ketone with NaBO4 in the presence of CeCl3 · 7H2O afforded regio- and stereoselectively drim-8-en-7β-ol in a high yield. Its dehydration with H2SO4 under mild conditions led to drim-7,9(11)-diene. Noncatalytic oxidation of drim-7,9(11)-diene with OsO4 and the catalytic oxidation with the pair OsO4–NMO gave, in a high yield, depending on conditions, driman-7β,8β,9α,11-tetraol or its mixture with drim-7-en-9α,11-diol and drim-9(11)-en-7α,8α-diol. Under optimal conditions the total yield of these diols reached 89%. The separate, noncatalytic oxidation of drim-7-en-9α,11-diol and of drim-9(11)-en-7α,8α-diol with OsO4 afforded driman-7α,8α,9α,11-tetraol. 相似文献
94.
It is shown that in several cases where planar delocalisation in organic cations would result in the formation of an anti-aromatic system, polyhedral delocalisation is the form of bonding actually preferred. This explains, for instance, why organic cations in such cases adopt cage-like structures. A full graph-theoretical analysis, similar to one previously published12 for polyhedral boranes, carboranes and metal clusters, indicates that the nido structure for (CH)5+ may readily be accounted for. Moreover, in the case of the dication (CH)62+ the fact that its energy minimum also corresponds to a nido structure is explained. In fact, no closo- or arachno-type structures appear to be possible for organic cations. A number of structural predictions concerning these species are given in the conclusion. 相似文献
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98.
Miculescu Radu Mihail Alexandru Urziceanu Silviu-Aurelian 《Numerical Algorithms》2020,83(4):1399-1413
Numerical Algorithms - We provide a new algorithm (called the grid algorithm) designed to generate the image of the attractor of a generalized iterated function system on a finite dimensional space... 相似文献
99.
Alexandru Chirvăsitu 《Journal of Algebra》2010,323(5):1593-1606
100.
The complete list of constraint manifolds having the group structure is given. 相似文献