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21.
V. V. Gritsenko O. A. D'yachenko D. V. Konarev R. N. Lyubovskaya 《Russian Chemical Bulletin》2000,49(1):102-105
A new C70-based molecular complex 4BNDY·3C70·4C6H6 (1) (BNDY is binaphtho[1,8-d.e]-1,3-dithiin-2-ylidene) was prepared, and its full X-ray diffraction study at room temperature was performed. The C70 molecules in crystal 1 are ordered in different ways, and their ordering depends on van der Waals interactions between them
and nonplanar BNDY molecules in the boat conformation. The neighboring BNDY molecules in the structure are bound to each other
by π-π interactions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 99–102, January, 2000. 相似文献
22.
Marchenkova M. A. Konarev P. V. Boikova A. S. Ilina K. B. Pisarevsky Yu. V. Kovalchuk M. V. 《Crystallography Reports》2022,67(2):309-309
Crystallography Reports - An Erratum to this paper has been published: https://doi.org/10.1134/S1063774521340046 相似文献
23.
Konarev DV Neretin IS Slovokhotov YL Yudanova EI Drichko NV Shul'ga YM Tarasov BP Gumanov LL Batsanov AS Howard JA Lyubovskaya RN 《Chemistry (Weinheim an der Bergstrasse, Germany)》2001,7(12):2605-2616
New molecular complexes of fullerenes C60 and C70 with tetraphenylporphyrins [M(tpp)] in which M-H2, MnII, CoII, CuII, ZnII and Fe(III)Cl, have been synthesised. Crystal structures of two C60 complexes with H2TPP, which differ only in the number of benzene solvated molecules, and C60 and C70 complexes with [Cu(tpp)] have been studied. The fullerene molecules form a honeycomb motif in H2TPP.2C60. 3C6H6, puckered graphite-like layers in H2TPP.2C60.4C6H6, zigzag chains in [Cu(tpp)].C70.1.5C7H8.0.5C2HCl3 and columns in [Cu(tpp)]2.C60. H2TPP has van der Waals contacts with C60 through nitrogen atoms and phenyl groups. Copper atoms of the [Cu(tpp)] molecules are weakly coordinated with C70, but form no shortened contacts with C60. The formation of molecular complexes with fullerenes affects the ESR spectra of [M(tpp)] (M = Mn, Co and Cu). [Mn(tpp)] in the complex with C70 lowers its spin state from S = 5/2 to S = 1/2, whereas [Co(tpp)] and [Cu(tpp)] change the constants of hyperfine interaction. ESR, IR, UV-visible and X-ray photoelectron spectroscopic data show no noticeable charge transfer from the porphyrinate to the fullerene molecules. 相似文献
24.
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26.
A. A. Konarev E. A. Lukyanets V. M. Negrimovskii 《Russian Journal of Electrochemistry》2007,43(11):1252-1259
The electroreduction of methyl 5-nitro-4-oxopentanate was studied by means of a polarographic method and preparative electrolysis in acidic-alcoholic solutions. The effects of the following factors on the yield and quality of 5-amino-4-oxopentanoic acid hydrochloride were studied: the cathode material, amount of electricity, temperature, nature of the solvent, concentrations of the initial nitro compound and hydrochloric acid, and the cell design. It was shown by electrolysis at a controlled potential and in a galvanostatic mode that the products of methyl 5-nitro-4-oxopentanate electroreduction are hydroxyamino and amino compounds, and also ammonium chloride, nitromethane, methylhydroxylamine hydrochloride, and monomethylamine hydrochloride. Their ratio depends on the electrolysis conditions. The highest overall substance yield (61.1–66.0%) and current yield (68.1–68.6%) of 5-amino-4-oxopentanoic acid hydrochloride was achieved at a copper cathode in a filter-press cell. The content of the main substance in the electrochemically obtained samples of 5-amino-4-oxopentanoic acid was 89.5–91.0%. 相似文献
27.
Dr. Dmitri V. Konarev Dr. Salavat S. Khasanov Dr. Alexey V. Kuzmin Dr. Maxim V. Mikhailenko Dr. Akihiro Otsuka Prof. Hideki Yamochi Prof. Hiroshi Kitagawa Prof. Dr. Rimma N. Lyubovskaya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17470-17480
Crystalline {Cryptand[2.2.2](Na+)}{HAT(CN)6.−}⋅0.5C6H4Cl2 ( 1 ), {Cryptand[2.2.2](K+)}{HAT(CN)6.−} ( 2 ), (CV+){HAT(CN)6.−} ( 3 ), and (CV+){HAT(CN)6.−}⋅2C6H4Cl2 ( 4 ) salts (where CV+ is the crystal violet cation) containing hexaazatriphenylenehexacarbonitrile radical anions have been obtained. The solid-state molecular structure as well as the optical and magnetic properties of HAT(CN)6.− are studied. The formation of HAT(CN)6.− in 1 – 4 leads to the appearance of new bands in the visible range, at 694 and 740 nm. The HAT(CN)6.− radical anions have spin state S=1/2 and are packed in one-dimensional stacks containing the {HAT(CN)6.−}2 dimers alternated with weaker interacting pairs of HAT(CN)6.− in 1 and nearly isolated {HAT(CN)6.−}2 dimers in 2 . The {HAT(CN)6.−}2 dimers are diamagnetic in 1 but they effectively mediate one-dimensional antiferromagnetic coupling of spins within the stacks with moderate exchange interaction of J/kB = −80 K. The behaviour of salt 2 is described by a singlet–triplet model for the {HAT(CN)6.−}2 dimers with an energy gap of 434(±7) K. Magnetic behaviour of both salts agree well with the data of extended Hückel calculations. Salts 3 and 4 contain isolated stacks of alternated HAT(CN)6.− and CV+ ions, and in this case, nearly paramagnetic behaviour is observed with Weiss temperatures of −1 and −7 K, respectively. Narrow Lorentzian EPR signals with g = 2.0033–2.0039 were found for the HAT(CN)6.− radical anions in 1 and 4 but in solution g-factor shifts to 1.9964. The electronic structure of HAT(CN)6.− is analysed based on X-ray diffraction data for 2 , showing a Jahn–Teller distortion of the radical anion that reduces the symmetry from D3h to Cs and splits the initially degenerated LUMOs. 相似文献
28.
Electrochemical behavior of 2,4-dinitrochlorobenzene was studied using the method of preparative electrolysis in an acidic
medium. The effect of the cathode material, temperature, nature of the solvent, concentrations of the initial dinitro compound
and hydrochloric acid on the current efficiency of chloronitroanilines and their ratio was studied. Conditions of electrosynthesis
of chloronitroanilines with predominant content of 2-chloro-5-nitroaniline (72–76 %) in the reaction solutions are found providing
the yield of chloronitroanilines of 83–86% and the current efficiency of about 100%. 相似文献
29.
Konarev DV Khasanov SS Otsuka A Saito G Lyubovskaya RN 《Journal of the American Chemical Society》2006,128(29):9292-9293
A negatively charged pi-(C60-)2 dimer bonded by two single bonds was found in the ionic multicomponent complex {(MDABCO+).CoIITMPP}2.(C60-)2.(C6H4Cl2)2.5.(C6H5CN)1.5 (1). In contrast to the previously described diamagnetic sigma-(C60-)2 dimer, the negatively charged pi-dimer has a biradical state at room temperature: (C60*-)2 (S = 1). The behavior of spins in this dimer can be described by a model with a singlet ground state (S = 0) and a close lying excited triplet (S = 1) state with the energy gap of 2|JAF| = 70 +/- 2 cm-1. On the whole, complex 1 shows a strong antiferromagnetic interaction of spins with a Weiss constant of -34 K. 相似文献
30.
Konarev DV Khasanov SS Kovalevsky AY Saito G Otsuka A Lyubovskaya RN 《Dalton transactions (Cambridge, England : 2003)》2006,(30):3716-3720
Single crystals of the ionic C60 complex with bis(benzene)chromium: {Cr(I)(C6H6)2(.+)}.(C60.-)).C6H4Cl2 (1) were obtained. The crystal structure of 1 shows the presence of monomeric C60.- radical anions at 250 K and the formation of single-bonded (C60-)2 dimers at 90 K. The dimerization is realized in two types of the C60.-) pairs with different interfullerene center-to-center distances of 10.052 and 10.279 A arranged in zigzag chains along the a-direction. As a result, two symmetrically independent (C60-)2 dimers found in 1 at 90 K have different environments, intercage C-C bond lengths and C60- center-to-center distances. Such differences should provide different thermal stability of these dimers and result in the appearance of two stages at the dimerization. Indeed, according to SQUID measurements, the magnetic moment of 1 decreases stepwise at the dimerization in two temperature ranges at 240-200 and 200-160 K. 相似文献