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61.
Yu. S. Syroeshkina L. L. Fershtat M. A. Syroeshkin V. V. Kuznetsov K. A. Lyssenko N. N. Makhova 《Russian Chemical Bulletin》2009,58(5):1002-1006
Complexes of bicyclic diaziridines 6,6′-bi(1,5-diazabicyclo[3.1.0]hexane) (L
1
) and 6-(4-methoxyphenyl)-1,5-diazabicyclo[3.1.0]hexane (L
2
) with the salts Cd(NO3)2 · 4H2O and Cd(ClO4)2 · 6H2O have been synthesized. The fact of complexation has been established by cyclic voltammetry. The crystal structure of complex
L
1
with Cd(NO3)2 (the coordination number of cadmium is 8) has been studied by X-ray diffraction. 相似文献
62.
Yu. S. Syroeshkina V. V. Kuznetsov K. A. Lyssenko N. N. Makhova 《Russian Chemical Bulletin》2009,58(2):366-379
The present study revealed two new reactions resulting in the diaziridine ring expansion, viz., the insertion of the CS2 molecule and the CN group of activated nitriles into the C—N bond of the diaziridine fragment of 6-aryl-1,5-diazabicyclo[3.1.0]hexanes.
These reactions can be performed only in ionic liquids in the presence of BF3 · Et2O as the catalyst. Based on these reactions, we developed simple one-pot methods for the synthesis of 3-aryldihydro-5 H-pyrazolo[1,2- c][1,3,4]thiadiazole-1-thiones and 1-aryl-6,7-dihydro-1 H,5H-pyrazolo-[1,2-a][1,2,4]triazoles in high yields. Dipolar intermediates of new reactions, which are direct precursors of the final products,
were detected by NMR methods. One of the intermediates was isolated and characterized. The reaction of 6-aryl-1,5-diazabicyclo[3.1.0]hexanes
with benzoyl cyanide affords (2-benzoyrpyrazolidin-1-yl)(aryl)acetonitriles. 相似文献
63.
Ogurtsov V. A. Karpychev Yu. V. Belyakov P. A. Nelyubina Yu. V. Lyssenko K. A. Rakitin O. A. 《Russian Chemical Bulletin》2009,58(2):430-436
The reaction of 1,2-dithiol-3-thiones with isonitriles at room temperature affords imino-1,3-dithietanes. The reaction is
reversible. According to 1H NMR spectroscopy, the rise of the temperature shifts the equilibrium to the starting compounds. The structure of one of
the imino-1,3-dithietanes was established by X-ray diffraction. 相似文献
64.
Alexander A. Korlyukov Sergey A. Pogozhikh Konstantin A. Lyssenko Aleksander G. Shipov Evgeniya P. Kramarova Igor P. Yakovlev 《Journal of organometallic chemistry》2006,691(19):3962-3975
(C,O)-chelate silanol hydrohalides RC(O)NHCH2SiMe2OH · HHal (2a,b and 5b), and their precursors, (C,O)-chelate chlorosilanes RC(O)NHCH2SiMe2Cl (6a,b) and disiloxanes [RC(O)NHCH2SiMe2]2O (8a,b) (R = Me (a), Ph (b); Hal = Cl (2), Br (5)), were obtained by several routes. The original scheme of hydrolysis of the above chlorides was discussed in detail. X-ray analysis has shown that the silanol hydrohalogenides PhC(O)NHCH2SiMe2OH · HX (2b and 5b) in the crystal exist in the form of cation-anion pairs [PhC(O)NHCH2SiMe2(OH2)]+ · X− (14b · Cl− and 14b · Br−) assembled by H-bonds in a 3D framework. The Si atom in the cation has a trigonal bipyramidal configuration with the oxygen atom of the carbonyl group and protonated hydroxyl exo-substituent in axial positions. The endocyclic Si-O bonds are equal with an average of 1.905 Å while the exocyclic Si-O bonds are 1.979 and 2.009 Å, for Hal = Cl and Br, respectively.Quantum chemical calculations have shown that the cation [PhC(O)NHCH2SiMe2(OH2)]+ (14b) is stable only in the crystal. Based on a high-resolution X-ray study and a quantum chemical calculation, it was found that the chemical bonding pattern in the OSiO axial fragment of the cation 14b corresponds to a three-centred four electron interaction. The cation 14b should be considered as a silylium cation stabilized by coordinated H2O molecules rather than a silyloxonium ion. 相似文献
65.
Andrey S. Sigachev Angelina N. Kravchenko Galina A. Gazieva Pavel A. Belyakov Natal'Ya G. Kolotyrkina Oleg V. Lebedev Nina N. Makhova Konstantin A. Lyssenko 《Journal of heterocyclic chemistry》2006,43(5):1295-1302
The first representatives of 3,3′‐bi(2,4‐dioxa‐6,8‐diazabicyclo[3.3.0]octan‐7‐ones) have been synthesized by a reaction of glyoxal as form of 2,2′‐bi(4,5‐dihydroxy‐1,3‐dioxalane) with N,N′‐dialkylureas. Their structures have been supported by X‐ray analysis. 1,3‐Dialkylimidazolidine‐2,4‐diones (hydantoins) have been isolated as by‐products and their formation mechanism has been experimentally confirmed. 相似文献
66.
A planar chiral non-metallocenic analogue of the most popular N,N-dimethylbenzylaminate palladacycle
Valery V. Dunina Eugeniya I. TurubanovaOlga N. Gorunova Michail V. LivantsovKonstantin A. Lyssenko Dmitrii Yu. AntonovYuri K. Grishin 《Polyhedron》2012,31(1):413-421
A racemic planar chiral tertiary amine pCp-CH2NMe2 (HL1, pCp = [2.2]paracyclophane-4-yl) was prepared by aminomethylation of the bromide pCp-Br with Eschenmoser’s salt. Direct cyclopalladation of this new ligand with palladium(II) acetate results in the formation of the racemic CN-dimer rac-3 in a moderate yield of 64%. The enantiomerically pure dimer (Spl, Spl)-3 was obtained by the standard procedure of racemic palladacycle resolution using (SC)-prolinate as a chiral derivatising agent. The ortho-palladated structure, absolute configuration of the chiral plane and stereochemical peculiarities of the new CN-palladacycle were established by means of NMR spectroscopy and an X-ray diffraction study of its (SC)-prolinate derivative. 相似文献
67.
T. W. Canzler C. P. Holfeld F. Lser V. G. Lyssenko K. Leo D. M. Whittaker K. Khler 《Physica E: Low-dimensional Systems and Nanostructures》2001,10(4):787
We use semiconductor superlattices as a model system for the investigation of Fano resonances. In absorption the excitonic transitions of the Wannier–Stark ladder show the typical asymmetric line shape due to coupling to the continuum of lower-lying transitions. The unique feature of these Fano resonances is that they allow to continuously tune the key parameter – the coupling strength Γ between the discrete state and the degenerate continuum – by varying the bias voltage. Using this feature, we directly show that the Fano coupling leads to a fast polarization decay. We also investigate the dependence of the Fano parameters on the structure of the superlattice and compare with an extensive theoretical model of the resonances. 相似文献
68.
Irina L. Odinets Oleg I. Artyushin Evgenii I. Goryunov Konstantin A. Lyssenko Ekaterina Yu. Rybalkina Ilya V. Kosilkin Tatiana V. Timofeeva Mikhail Yu. Antipin 《Heteroatom Chemistry》2005,16(6):497-502
In a search for cytotoxic fluorescent materials, a series of N‐phosphorylated compounds 2a–c were prepared by phosphorylation of 3,5‐bis(4‐N,N‐dimethylbenzylidene)‐4‐piperidone 1 . According to X‐ray investigations, molecule 2a is E,E‐isomer with axial position of the P(O)(OCH2CF3)2 substituent. Fluorescence of compounds 2a–c was found to be similar to fluorescence of nonphosphorylated compound 1 . The cytotoxicity of the compounds 2a–c was estimated on several human tumor cell lines (H9, K562, and MCF7). © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:497–502, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20147 相似文献
69.
Reactions of the Tröger base (1) with HgBr2 and Mel proceed with the participation of only one N atom. According to the data of X-ray diffraction analysis, the complex [(±)-1]2·HgBr2 crystallizes in the achiral space groupP n . Unlike the complex [(+)-1]2·HgBr2, methiodide of (+)-1 in MeOH undergoes racemization at 20°C. The virtual spin-spin coupling constants4 J HH observed for the base (C 2 symmetry) are transformed into the “usual” constants in the case of the desymmetrized methiodide system. 相似文献
70.
A. I. Shif S. N. Lyubchenko O. Ya. Borbulevych O. V. Shishkin K. A. Lyssenko L. P. Olekhnovich 《Russian Chemical Bulletin》1999,48(1):139-146
Oxidation of 4,6-di-tert-butylpyrogallol gave two dimeric products instead of the expected 4,6-di-tert-butyl-3-hydroxy-1,2-benzoquinone (2). It was established by X-ray diffraction analysis that the first product has the structure
of tetra-tert-butyl-6, 10a-dihydroxy-1,2-dioxo-3,4a,7,9-1,2,4a, 10a-tetrahydrodibenzo-1,4-dioxine. From this it follows that compound 2
undergoes regio- and stereospecific dimerization according to the [2π+4π]-cycloaddition mechanism,viz, the hetero Diels—Alder reaction. The double intensities of the signals in the1H NMR spectrum are indicative of a symmetrical structure of the second product, 2,6,4′, 6′-tetra-tert-butyl-4,4′-dihyroxy-3,5,3′,5′-tetraoxo-4,4′-bi(cyclohexene), which is a racemate of enantiomers formed upon recombination
(r+r orl+l) of the intermediate of oxidation of pyrogallol, namely, of ther,l-stereogenic 3,5-di-tert-butyl-1-hydroxy-2,6-dioxocyclohex-3-enyl radical.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 139–146, January, 1999. 相似文献