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排序方式: 共有189条查询结果,搜索用时 31 毫秒
131.
T. A. Panina V. P. Koshcheev D. A. Morgun N. V. Safin 《Bulletin of the Russian Academy of Sciences: Physics》2010,74(2):161-164
Expressions for the potential energy of interaction between a fast neutral atom or a multiply charged ion and a crystal atom
are obtained, both with and without regard for the Pauli principle. Results from computer simulation of the heating of silver
ions with a fixed value of the charge state in passing through the (110) planar channel of a silicon crystal are presented.
It is shown that the rate of dechanneling can be estimated by the form of the potential energy of interaction of an incident
ion with a continuous potential of the planar crystal channel. 相似文献
132.
Analytical expressions are obtained for the angular distributions and spin asymmetries of the processes of elastic electromagnetic
and electroweak scattering of high energy electrons on polarized/unpolarized proton target with account of C-, P- and T/CP-invariance violating anapole and electric dipole moments, as well as neutral weak electric, magnetic and axial form factors
of the proton. Behavior of the P- and T- odd spin asymmetries is studied in dependence of the electron’s energy and scattering angle and proton form factors parameters. 相似文献
133.
Maria G. Babashkina Damir A. Safin Michael Bolte Axel Klein 《Heteroatom Chemistry》2010,21(7):486-491
The reaction of the lithium salts of N‐phosphorylated thioureas RC(S)NHP(O)(OiPr)2 (R = 1‐aza‐15‐crown‐5, HL I ; 1‐aza‐12‐crown‐4, HL II ) with Co(II) or Ni(II) leads to the chelate complexes [ ML I,II 2 ]. The metal center is found in a tetrahedral ([ CoL I,II 2 ]) or square planar ([ NiL I,II 2 ]) O2S2 environment formed by the CS sulfur atoms and the PO oxygen atoms of two deprotonated ligands L . The molecular structure of [ CoL I 2 ] was elucidated by X‐ray diffraction and the extraction properties of HL I,II and [ ML I,II 2 ] toward alkali metal and ammonium picrates were investigated. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:486–491, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20637 相似文献
134.
Babashkina MG Safin DA Bolte M Srebro M Mitoraj M Uthe A Klein A Köckerling M 《Dalton transactions (Cambridge, England : 2003)》2011,40(13):3142-3153
Reaction of the deprotonated N-thiophosphorylated thioureas RNHC(S)NHP(S)(OiPr)(2) (R = Ph, HL(I); 2-MeC(6)H(4)-, HL(II); 2,6-Me(2)C(6)H(3)-, HL(III); 2,4,6-Me(3)C(6)H(2)-, HL(IV); Me-, HL(V)) with Ni(II) leads to complexes of the formula [NiL(I-V)(2)]. The molecular structures of the thioureas HL(II-V) and the complexes [NiL(II-V)(2)] in the solid were elucidated by single-crystal X-ray diffraction analysis. In the complexes, the metal is found to be in a square planar trans-N(2)S(2) ([NiL(II-IV)(2)]) environment formed by the C=S sulfur atoms and the P-N nitrogen atoms, or in a square planar trans-S(2)S'(2) ([NiL(V)(2)]) environment formed by the C=S and P=S sulfur atoms of two deprotonated ligands. DFT calculations confirmed that the [Ni(L(II-IV)-N,S)(2)] isomers are more stable (by 16-21 kcal mol(-1)) than the corresponding [Ni(L(II-IV)-S,S')(2)] conformers. The main reason for higher stability of the 1,3-N,S vs. 1,5-S,S' isomers is the formation of intramolecular N-H···S=P hydrogen bonds. In solution the complexes [Ni(L(II-V)-N,S)(2)] have an exclusive 1,3-N,S coordination, while the compound [Ni(L(I)-N,S)(2)] exhibits two isomers in the (1)H and (31)P NMR spectra. The major species is assigned to the 1,3-N,S coordinated isomer, while the minor (~25%) signals are due to the 1,5-S,S' isomer. UV-Vis spectroscopic results are in line with this. The electrochemical measurements reveal reversible one-electron reduction and irreversible oxidations, both assigned to ligand-centred processes. 相似文献
135.
K. L. Safin 《Algebra and Logic》1998,37(4):260-269
Based on the notion of an ideal of an iterative algebra, developed earlier, we introduce the concept of a simple iterative
algebra of functions of a k-valued logic, that is, an algebra freed of proper ideals. It is found out that every simple algebra
is contained in a maximal algebra and is naturally associated with some permutation group on a finite set. We specify a number
of conditions on a permutation group under which a corresponding algebra is said to be maximal and simple. This allows us
to completely list the maximal simple algebras for the case where k<-4.
Translated fromAlgebra i Logika, Vol. 37, No. 4, pp. 460–477, July–August, 1998. 相似文献
136.
Unprecedented Trinuclear AgI Complex with 2,4,6‐Tris(2‐pyrimidyl)‐1,3,5‐triazine as an Efficient Catalyst for the Aziridination of Olefins 下载免费PDF全文
Dr. Damir A. Safin Dr. Amélie Pialat Dr. Ilia Korobkov Prof. Muralee Murugesu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(16):6144-6149
An unprecedented trinuclear heteroleptic AgI complex was isolated using a stable multidentate 2,4,6‐tris(2‐pyrimidyl)‐1,3,5‐triazine (TPymT) ligand. The obtained compound is an efficient catalyst for the direct aziridination of terminal olefins. 相似文献
137.
Novel Peptide Chemistry in Terrestrial Animals: Natural Luciferin Analogues from the Bioluminescent Earthworm Fridericia heliota 下载免费PDF全文
Maxim A. Dubinnyi Aleksandra S. Tsarkova Valentin N. Petushkov Zinaida M Kaskova Natalja S. Rodionova Sergey I. Kovalchuk Rustam H. Ziganshin Mikhail S. Baranov Konstantin S. Mineev Ilia V. Yampolsky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3942-3947
We report isolation and structure elucidation of AsLn5, AsLn7, AsLn11 and AsLn12: novel luciferin analogs from the bioluminescent earthworm Fridericia heliota. They were found to be highly unusual modified peptides, comprising either of the two tyrosine‐derived chromophores, CompX or CompY and a set of amino acids, including threonine, gamma‐aminobutyric acid, homoarginine, and unsymmetrical N,N‐dimethylarginine. These natural compounds represent a unique peptide chemistry found in terrestrial animals and rise novel questions concerning their biosynthetic origin. 相似文献
138.
139.
Natal'ya V. Davletshina Rustam R. Davletshin Elnara A. Baturshina Aynaz Z. Gaynullin Airat R. Garifzyanov Rafael A. Cherkasov 《Phosphorus, sulfur, and silicon and the related elements》2016,191(11-12):1671-1672
ABSTRACTMembrane transport properties of the new lipophilic phosphorylated azapodands toward Сa(II), Ва (II), Mg(II), and Sr(II) were studied. The investigation of the processes of passive membrane ion transport showed the high values of the transfer flow of the alkaline earth metals’ ions with all carriers. It was found that N,N’-bis(di-p-tolylphosphorylmethyl)-1,8-diamino-3,6-dioxaoctane (I) is the most effective carrier among all compounds studied. 相似文献
140.