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161.
Migulin VA Krayushkin MM Barachevsky VA Kobeleva OI Valova TM Lyssenko KA 《The Journal of organic chemistry》2012,77(1):332-340
Nonsymmetric cyclopentene-based dithienylethenes, containing both thienyl and benzothienyl units, have been synthesized for the first time, employing intramolecular McMurry reaction as a key transformation to target compounds 10 and 16. Photochromic properties of these compounds were examined in toluene and acetonitrile solutions, PMMA layers, solid films, and crystal phase. To explain an unprecedented single-crystalline photochromism phenomena of 10, X-ray crystallographic analysis was performed, revealing a significant influence of strong S···S interatomic interactions on the intramolecular distance between two photochemical reaction centers in the molecule. Compound 16 could be further synthetically modified in a step-by-step manner, thus serving as potential key intermediate to various complex bifunctional photochromic molecules. 相似文献
162.
163.
Kravchenko A. N. Sigachev A. S. Belyakov P. A. Ilyin M. M. Lyssenko K. A. Davankov V. A. Lebedev O. V. Makhova N. N. Tartakovsky V. A. 《Russian Chemical Bulletin》2009,58(6):1264-1269
Russian Chemical Bulletin - The α-ureidoalkylation of N-(hydroxyalkyl)ureas (ureido alcohols) with 1,3-H2- and 1,3-Me2-4,5-dihydroxyimidazolidin-2-ones was systematically studied. The yields... 相似文献
164.
V. I. Simakov Yu. Yu. Gorbanev T. E. Ivakhnenko V. G. Zaletov K. A. Lyssenko Z. A. Starikova E. P. Ivakhnenko V. I. Minkin 《Russian Chemical Bulletin》2009,58(7):1361-1370
The reaction of di(tert-butyl) derivatives of pyrocatechol with 2,6-dihydroxyaniline afforded 2,4,6,8-tetra(tert-butyl)-9-hydroxyphenoxazin-1-one. The chemical properties of the reaction product and its ability to form complexes with
metal salts as the tridentate ligand were investigated. The structure of hydroxyphenoxazinone was established by X-ray diffraction. 相似文献
165.
V. V. Burlakov V. S. Bogdanov K. A. Lyssenko A. Spannenberg P. V. Petrovskii W. Baumann P. Arndt M. Kh. Minacheva B. N. Strunin U. Rosenthal V. B. Shur 《Russian Chemical Bulletin》2012,61(1):165-173
The interaction of the Negishi reagent Cp2ZrBun 2 with 1,4-bis(tert-butyl)butadiyne ButC≡C-C≡CBut leads to four products: a five-membered zirconacyclocumulene complex Cp2Zr(η4-ButC4But) (2) synthesized earlier by another method, the previously unknown seven-membered zirconacyclocumulene Cp2Zr[η4-ButC4(But)-C(C2But)=CBut] (3) as well as small amounts of the zirconocene binuclear butatrienyl complex Cp2(Bun)Zr(ButC4But)Zr(Bun)Cp2 (4), and the dimeric acetylide [Cp2ZrC≡CBut]2 (5). The structure of complexes 2–5 was established by X-ray diffraction studies. 相似文献
166.
A. Yu. Lepeshkin K. F. Turchin E. G. Gal’pern I. V. Stankevich K. A. Lyssenko V. S. Velezheva 《Russian Chemical Bulletin》2007,56(7):1447-1455
Based on the results of studies of the deuterium exchange and dehydration of 4-hydroxy-Δ2-thiazolines and 2-R-4-acetyl-8b-hydroxy-3a,8b-dihydro-4H-thiazolo[5,4-b]indoles containing the α-methylene (methine) unit at the C(2) atom, the mechanism of dehydration of these compounds generated
as intermediates in the Hantzsch synthesis of thiazoles and 2-R-4-acetyl-4H-thiazolo[5,4-b]indoles was proposed. This mechanism includes an additional step of the formation of the corresponding Δ3-thiazolines. According to the results of quantum chemical calculations, this is energetically more favorable than the dehydration
in terms of the commonly accepted mechanism. In some cases, an acidic medium impedes the dehydration of 4-hydroxy-Δ2-thiazolines or their cyclic analogs. The proposed mechanism provides an explanation for the empirical data on the differences
in the reactivities of both thioamides and α-haloketones, which have remained unexplained in terms of the commonly accepted
mechanism. The spontaneous thiazole synthesis is virtually impossible starting from thioamides of aromatic or heteroaromatic
acids and α-haloketones bearing electron-withdrawing α′ substituents or cyclic bromoindoxyl-type haloketones. In the thiazole
synthesis from these starting components, it is expedient to perform dehydration under basic catalysis.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1394–1402, July, 2007. 相似文献
167.
S. A. Pisareva P. V. Petrovskii K. A. Lyssenko M. Yu. Antipin E. E. Nifant’ev 《Russian Chemical Bulletin》2004,53(9):2008-2012
The reaction of 1,1,1-tris(chloromethyl)propane with diphenylphosphine under phase-transfer conditions afforded 1,1,1-tris(diphenylphosphinomethyl)propane, whose oxidation gave a previously unknown representative of trigonal tris(phosphine oxides), viz., stable 1,1,1-tris(diphenylphosphorylmethyl)propane. Its analogs, viz., bis(diphenylphosphoryl)diphenylphosphinomethane and tris(diphenylphosphoryl)methane, are unstable in air and decompose with the cleavage of the P-C bond.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1926–1929, September, 2004. 相似文献
168.
Gursky M. E. Baranin S. V. Lyssenko K. A. Chudakova O. O. Bubnov Yu. N. 《Russian Chemical Bulletin》2022,71(8):1729-1736
Russian Chemical Bulletin - A total synthesis of both pairs of enantiomers of natural lignans, diaeudesmin and epieudesmin, was described. The synthesis involved enantioselective allylborylation of... 相似文献
169.
170.
K. A. Lyssenko D. G. Golovanov V. I. Meshcheryakov A. R. Kudinov M. Yu. Antipin 《Russian Chemical Bulletin》2005,54(4):933-941
The character of electron density distribution in the C2B3 open face, the influence of the SMe2 group on the character of electron density distribution, and the nature of the sodium—anion interaction were studied based
on the data of high-resolution X-ray diffraction study of crystals of the sodium salt of charge compensated nido-carborane [9-SMe2-7,8-C2B9H10]− and quantum-chemical calculations for the Na...H—B bonded dimer, the isolated [9-SMe2-7,8-C2B9H10]− anion, and the [7,8-C2B9H10]2− dianion. The character of electron density distribution in the C2B3 open face is analogous to the electron distribution in the cyclopentadienyl ligand. In nido-carborane, a substantial charge redistribution takes place compared to that observed in the closo analogs. The topological analysis of the electron density distribution function demonstrated that the cation—anion interactions
are determined predominantly by Na...H—B contacts. The total energy of these contacts in the { [9-SMe2-7,8-C2B9H10]Na(thf)2}2 dimer estimated from X-ray diffraction data is 11.74 kcal mol−1.
Dedicated to Corresponding Member of the Russian Academy of Sciences E. P. Serebryakov on the occasion of his 70th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 911–918, April, 2005. 相似文献