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21.
Victor Ch. Kravtsov Vasile Lozovan Nikita Siminel Eduard B. Coropceanu Olga V. Kulikova Natalia V. Costriucova Marina S. Fonari 《Molecules (Basel, Switzerland)》2020,25(23)
Eight mixed-ligand coordination networks, [Cd(2-aba)(NO3)(4-bphz)3/2]n·n(dmf) (1), [Cd(2-aba)2(4-bphz)]n·0.75n(dmf) (2), [Cd(seb)(4-bphz)]n·n(H2O) (3), [Cd(seb)(4-bpmhz)]n·n(H2O) (4), [Cd(hpa)(3-bphz)]n (5), [Zn(1,3-bdc)(3-bpmhz)]n·n(MeOH) (6), [Cd(1,3-bdc)(3-bpmhz)]n ·0.5n(H2O)·0.5n(EtOH) (7), and [Cd(NO3)2(3-bphz)(bpe)]n·n(3-bphz) (8) were obtained by interplay of cadmium nitrate tetrahydrate or zinc nitrate hexahydrate with 2-aminobenzenecarboxylic acid (H(2-aba)), three dicarboxylic acids, sebacic (decanedioic acid, H2seb), homophthalic (2-(carboxymethyl)benzoic acid, H2hpa), isophthalic (1,3-benzenedicarboxylic acid, H2(1,3-bdc)) acids, bis(4-pyridyl)ethane (bpe) and with four azine ligands, 1,2-bis(pyridin-4-ylmethylene)hydrazine (4-bphz), 1,2-bis(1-(pyridin-4-yl)ethylidene) hydrazine (4-bpmhz), 1,2-bis(pyridin-3-ylmethylene)hydrazine (3-bphz), and 1,2-bis(1-(pyridin-3-yl) ethylidene)hydrazine (3-bpmhz). Compounds 1 and 2 are 1D coordination polymers, while compounds 3–8 are 2D coordination polymers. All compounds were characterized by spectroscopic and X-ray diffraction methods of analysis. The solvent uptakes and stabilities to the guest evacuation were studied and compared for 1D and 2D coordination networks. The de-solvated forms revealed a significant increase of emission in comparison with the as-synthesized crystals. 相似文献
22.
Nikita K. Kulachenkov Dapeng Sun Yuri A. Mezenov Andrei N. Yankin Sergey Rzhevskiy Vyacheslav Dyachuk Alexandre Nomin Ghouti Medjahdi Evgeny A. Pidko Valentin A. Milichko 《Angewandte Chemie (International ed. in English)》2020,59(36):15522-15526
We demonstrate herein an all‐optical switch based on stimuli‐responsive and photochromic‐free metal–organic framework (HKUST‐1). Ultrafast near‐infrared laser pulses stimulate a reversible 0.4 eV blue shift of the absorption band with up to 200 s?1 rate due to dehydration and concomitant shrinking of the structure‐forming [Cu2C4O8] cages of HKUST‐1. Such light‐induced switching enables the remote modulation of intensities of photoluminescence of single crystals of HKUST‐1 as well visible radiation passing through the crystal by 2 order of magnitude. This opens up the possibility of utilyzing stimuli‐responsive MOFs for all‐optical data processing devices. 相似文献
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The formalism developed in Part I [K. L. Ivanov, N. N. Lukzen, A. A. Kipriyanov, and A. B. Doktorov, Phys. Chem. Chem. Phys. 6, 1706 (2004)] of the present contribution is extended to treat the reacting particles with internal quantum states. Initial spatial correlations of reactants are considered in the framework of this formalism as well. 相似文献
26.
In the present work we suggest a method for calculating rate constants of chemical processes affected by mobility of reactants. The method is based on the encounter theory. Unlike the widely accepted model of collision complexes it provides a general formal solution for practically arbitrary reaction scheme. 相似文献
27.
Let X be an anisotropic projective quadric over a field F of characteristic not 2. The essential dimension dimes(X) of X, as defined by Oleg Izhboldin, is dimes(X)=dim(X)-i(X) +1, where i(X) is the first Witt index of X (i.e., the Witt index of X over its function field).Let Y be a complete (possibly singular) algebraic variety over F with all closed points of even degree and such that Y has a closed point of odd degree over F(X). Our main theorem states that dimes(X)dim(Y) and that in the case dimes(X)=dim(Y) the quadric X is isotropic over F(Y).Applying the main theorem to a projective quadric Y, we get a proof of Izhboldins conjecture stated as follows: if an anisotropic quadric Y becomes isotropic over F(X), then dimes(X)dimes(Y), and the equality holds if and only if X is isotropic over F(Y). We also solve Knebuschs problem by proving that the smallest transcendence degree of a generic splitting field of a quadric X is equal to dimes(X). To the memory of Oleg Izhboldin 相似文献
28.
Nikita Szidorov 《Acta Mathematica Hungarica》2003,98(4):345-355
The aim of this paper is to prove some fixed point theorems which generalize well known basic fixed point principles of nonlinear
functional analysis. Moreover, we investigate the class of mappings f: X→ X, where X is a Banach space, for which one of the main conditions in the metric fixed point theory, namely the condition (1), is satisfied.
We obtain essential applications of this fact. All our results are illustrated by suitable examples.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
29.
Volume Contents
K-Theory Contents of Volume 22 相似文献30.
Nikita M. Podvalnyy Alexander I. Zinin Nelly N. Malysheva Roman A. Kunetskiy 《Journal of carbohydrate chemistry》2013,32(5):213-224
A convenient synthesis and separation of α- and β-anomers of methyl (phenyl 3,5-dideoxy-2-thio-5-trifluoroacetamido-D-glycero-D-galacto-nonulopyranosid)onate (6a and 6b) on a multigram scale was developed. Both α- and β-isomers of 6 were obtained as crystals suitable for safe storage. The β-isomer forms a crystalline solvate with methanol. Fully O-trichloroacetylated and O-trifluoroacetylated N-trifluoroacetyl thiosialosides were synthesized in an efficient manner from the β-tetraol 6b. 相似文献