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231.
Matveev Vladimir B. Semenov-Tian-Shansky Michel 《Letters in Mathematical Physics》2019,109(6):1269-1270
Letters in Mathematical Physics - 相似文献
232.
A comprehensive comparison of different quantum-chemical methods applied to calculate the N2 ground state potential energy curve is presented. In the comparison we highlight the multireference state-specific (MRSS) coupled-cluster (CC) approach with the complete-active-space (CAS) reference and with single and double excitations from all reference determinants in the CC operator developed in our group. The method is called CASCCSD. The energy and amplitude equations for the method and the corresponding computer code have been generated using a computerized automative procedure that in the present work was extended to produce a parallel computer code. The complete CASCCSD wave function for N2 includes some selected eight-fold excitations in the CC operator. An analysis of the wave function estimates the importance of those excitations at large internuclear separations. 相似文献
233.
234.
Vladimir Gritsenko Grigory Kabatiansky Vladimir Lebedev Alexey Maevskiy 《Designs, Codes and Cryptography》2017,82(1-2):293-299
We prove new lower bounds on the rate of codes for noisy multiple access adder channel and discuss its application to the well-known coin weighing problem in the case when some measurements are incorrect. 相似文献
235.
A practical synthesis of new chiral aminophosphine ligands based on the camphane scaffold bearing alkoxy groups was accomplished. The application of these ligands in the Pd-catalyzed allylic alkylation of (E)-1,3-diphenyl-2-propenyl acetate proceeded with excellent conversions and ee’s of up to 91%. Variation of the alkoxy substituents did not substantially influence the catalytic performance. 相似文献
236.
237.
The 2,2,2-trichloroethoxycarbonyl (Troc) protecting group was efficiently removed from Troc-protected aliphatic and aromatic amines and also some Troc, Tos- and Troc, Ac-protected amines using activated mischmetal (MM). All reactions were performed by refluxing in dry tetrahydrofuran under an argon atmosphere and gave moderate to excellent yields. Several new compounds were synthesized, and new data about reactivity of Troc group were obtained. 相似文献
238.
Zhanna A. Krasnaya Vladimir A. Kuz’min Lyubov V. Litvinkova Evgeniya O. Dorofeeva Sergei G. Zlotin 《Mendeleev Communications》2013,23(4):212-214
New bischromophoric dyes (thiacarbocyanine and thiadicarbocyanine) containing coumarin moieties at each of the two benzothiazole systems, as well as monomethinecyanine containing coumarin moiety at only one heterocyclic system, manifest significant batho-chromic shift compared to relative coumarin-free dyes. 相似文献
239.
The electrophoretic mobility change of desferrioxamine B (DFO) was monitored by UV absorption spectrophotometry upon increasing the thorium(IV) concentration in the background electrolyte at two acidities ([HClO4]Tot = 0.0316 and 0.0100 M). These data enabled to assess the speciation model and to determine the equilibrium constant of [Th(DFO)H2]3+ at fixed ionic strength (I = 0.1 M (H,Na)ClO4). Affinity capillary electrophoresis (ACE) turned out to be most helpful in identifying the complexed species by ascertaining its charge and protonation state. The assignment of the correct stoichiometry relied on the reliable estimation of the electrophoretic mobility by assuming similar hydrodynamic radii for (DFO)H4+ and the chelate. The value of the apparent equilibrium constant (log β112 = 38.7 ± 0.4) obtained by ACE compares favorably well with those reported in the literature for thorium and a range of other metal ions, according to a linear free-energy relationship. This method is useful for studying metal-ligand binding equilibria and provides valuable information for further modelling the behavior of tetravalent actinides under environmental conditions. Structural information about the prevalent solution species in acidic conditions was gained by DFT calculations, confirming the bishydroxamato coordination mode of Th4+ by the diprotonated ligand. 相似文献
240.
Dr. Vladimir V. Shilovskikh Alexandra A. Timralieva Pavel V. Nesterov Dr. Alexander S. Novikov Dr. Petr A. Sitnikov Prof. Elizaveta A. Konstantinova Prof. Alexander I. Kokorin Prof. Ekaterina V. Skorb 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16603-16610
In the last two decades, a large number of self-assembled materials were synthesized and they have already found their way into large-scale industry and science. Hydrogen-bond-based supramolecular adducts are found to have unique properties and to be perfect host structures for trapping target molecules or ions. Such chemical systems are believed to resemble living matter and can substitute a living cell in a number of cases. Herein, a report on an organic material based on supramolecular assembly of barbituric acid and melamine is presented. Surprisingly, the structure is found to host and stabilize radicals under mild conditions allowing its use for biological applications. The number of free radicals is found to be easily tuned by changing the pH of the environment and it increases when exposed to light up to a saturation level. We describe a preparation method as well as stability properties of melamine–barbiturate self-assembly, potentiometric titration, and hydrogen ions adsorption data and EPR spectra concerning the composite. 相似文献