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Vladislav V. Klepov Anna A. Berseneva Kristen A. Pace Vancho Kocevski Mengqi Sun Peng Qiu Hui Wang Fanglin Chen Theodore M. Besmann Hans‐Conrad zur Loye 《Angewandte Chemie (International ed. in English)》2020,59(27):10836-10841
Most ternary sulfides belonging to the MGaS2 structure‐type have been known for many years and are well‐characterized. Surprisingly, there have been no reports of the NaGaS2 composition, which contains Na, a monovalent cation slightly larger in size than Li, found in LiGaS2, a compound known for its non‐linear optical properties. Now it is demonstrated for the first time that the unique reversible water absorption in NaGaS2 has resulted in its absence from previous reports owing to difficulties encountered when characterizing this compound by SC XRD. The layered structure of this compound coupled with uniquely easy migration of water molecules between the layers allows for ion exchange with 3d and 5f metal cations. Some cations, for example, Ni2+, facilitate exfoliation of the layers, providing a facile synthetic route to a new class of 2D chalcogenide materials and furthermore demonstrating that NaGaS2 can readily uptake uranyl species from aqueous solutions. 相似文献
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Navindra Keerthisinghe Matthew S. Christian Anna A. Berseneva Gregory Morrison Vladislav V. Klepov Mark D. Smith Hans-Conrad zur Loye 《Molecules (Basel, Switzerland)》2022,27(1)
The solvothermal synthesis, structure determination and optical characterization of five new metastable halometallate compounds, [1,10-phenH][Pb3.5I8] (1), [1,10-phenH2][Pb5I12]·(H2O) (2), [1,10-phen][Pb2I4] (3), [1,10-phen]2[Pb5Br10] (4) and [1,10-phenH][SbI4]·(H2O) (5), are reported. The materials exhibit rich structural diversity and exhibit structural dimensionalities that include 1D chains, 2D sheets and 3D frameworks. The optical spectra of these materials are consistent with bandgaps ranging from 2.70 to 3.44 eV. We show that the optical behavior depends on the structural dimensionality of the reported materials, which are potential candidates for semiconductor applications. 相似文献
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Fedorov B. S. Fadeev M. A. Kozub G. I. Chekhlov A. N. Konovalova N. P. Sashenkova T. E. Berseneva E. N. Dobrokhotova O. V. Tatyanenko L. V. 《Russian Chemical Bulletin》2011,60(6):1181-1184
Complexes of platinum tetrachloride with substituted nicotinamides and isonicotinamides were synthesized by the reactions
of the corresponding amides with hexachloroplatinic acid. All these complexes are low-toxic. The strong antimetastatic activity
of these complexes against Lewis lung carcinoma and B16 melanoma experimental tumors was found in an enzyme system and was
then shown in experiments on animals. 相似文献
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V. S. Berseneva N. Yu. Biryucheva V. A. Bakulev 《Chemistry of Heterocyclic Compounds》1993,29(12):1458-1461
It has been found that pyridinium- and isoquinoliniumthiocarbamoylazomethinylides react with esters of acetylenedicarboxylic and propiolic acids in two directions. The first direction is heterocyclization of the thioamide fragment of the ylide; under the influence of dimethyl acetylenedicarboxylate, a thiazolyl-4-one ring is formed, and by the interaction of the pyridiniumylide with methyl propiolate, a thiazin-4-one ring is formed. The second direction consists of annelation of the imidazole ring to the isoquinoline system upon reaction with methyl propiolate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1688–1691, December, 1993. 相似文献
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A new single-particle effective potential is proposed. This potential allows one to take into account quantum-electrodynamic (QED) corrections in relativistic calculations of many-electron ions and neutral atoms. In particular, it can be used in the Dirac-Fock (DF) method, the relativistic density functional, the multiconfiguration DF method, and the relativistic method of superposition of configurations. The potential is constructed without fitting parameters. Self-energy corrections have been calculated for a number of neutral alkali atoms and Li-like ions to check the quality of the nonlocal potential proposed. Comparison with the data in the literature on the QED corrections obtained in nonempirical calculations based on the use of QED perturbation theory is performed. 相似文献
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Gabrielle A. Leith Allison M. Rice Brandon J. Yarbrough Anna A. Berseneva Richard T. Ly Charles N. Buck III Dr. Denis Chusov Amy J. Brandt Prof. Dr. Donna A. Chen Benjamin W. Lamm Prof. Dr. Morgan Stefik Kenneth S. Stephenson Dr. Mark D. Smith Prof. Dr. Aaron K. Vannucci Dr. Perry J. Pellechia Prof. Dr. Sophya Garashchuk Prof. Dr. Natalia B. Shustova 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6056-6062
The effect of donor (D)–acceptor (A) alignment on the materials electronic structure was probed for the first time using novel purely organic porous crystalline materials with covalently bound two- and three-dimensional acceptors. The first studies towards estimation of charge transfer rates as a function of acceptor stacking are in line with the experimentally observed drastic, eight-fold conductivity enhancement. The first evaluation of redox behavior of buckyball- or tetracyanoquinodimethane-integrated crystalline was conducted. In parallel with tailoring the D-A alignment responsible for “static” changes in materials properties, an external stimulus was applied for “dynamic” control of the electronic profiles. Overall, the presented D–A strategic design, with stimuli-controlled electronic behavior, redox activity, and modularity could be used as a blueprint for the development of electroactive and conductive multidimensional and multifunctional crystalline porous materials. 相似文献
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EP Sheretov VS Gurov MV Dubkov OV Korneeva 《Rapid communications in mass spectrometry : RCM》1999,13(16):1699-1702
In this article we compare the classical monopole mass filter of von Zahn and the monopole mass filter with a hyperbolic V-shaped electrode. The experimental results and those of computer simulation for both mass spectrometers are presented. We show that the replacement of a conventional 90 degrees V-shaped electrode by an electrode with a hyperbolic profile substantially improves the peak shape of any given mass, and increases the mass resolution by a factor of 3-4 and the abundance sensitivity by a factor of 100. The potential of high analytical performance combined with electroforming techniques for electrode manufacture indicate future practical uses of such instruments. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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The discovery of neutron rich isotopes of the lightest elements on the neutron drip line exhibiting a halo structure has opened
up new vistas in research activities. The novel structural features associated with the halo phenomena have been the subject
for extensive theoretical and experimental investigations in recent times. In this talk, I propose to present a broad overview
of the recent developments in this field, bringing out the striking features which show that a large number oflight nuclei
near the neutron drip line are characterized by a clear separation between a ‘normal’ core nucleus and a loosely bound low
density veil of neutrons. Specifically, the two neutron halos offer a natural premises, from a theoretical standpoint, to
employ three body techniques for studying their detailed structural properties. A considerable part of the talk will be devoted
to report and highlight the results on a number of light halo nuclei such as 11Li, 11Be, 19B and 22C on which we have been carrying out investigations employing a simple but realistic three body model. These three body systems
which have been termed as ‘Borromean’ (i.e while three body systems are bound, the corresponding binary subsystems on the
other hand are unbound) are characterized by large spacial extension and very low separation energy of the neutron. They are,
therefore, ideally suited for exploring the possibility of the existence of Efimov states in two neutron halo nuclei. We have
recently carried out the three body analyses to predict the possibility of the occurrence of such states on which experimental
work at various laboratories is underway. 相似文献
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Yu. A. Azev O. S. Ermakova V. S. Berseneva V. A. Bakulev M. A. Ezhikova M. I. Kodess 《Russian Journal of Organic Chemistry》2017,53(1):90-95
6,7-Difluoroquinoxalin-2-one reacted with indoles, 5,5-dimethylcyclohexane-1,3-dione, 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, resorcinol, and pyrogallol on heating in acetic acid to give products of hydrogen substitution in the heterocyclic fragment. Heating of 6,7-difluoro-3-(1H-indol-3-yl)quinoxalin-2(1H)-ones with N-methylpiperazine gave the corresponding 7-(4-methylpiperazin-1-yl) derivatives. 相似文献