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有机金属聚合物的研究近几年得到了很大的发展,含金属Si、Ge、Sn的有机聚合物表现出特殊的导电性、非线性光学性等。我们合成了含Si、Ge、Sn的有机金属聚合物的中间体芳基硅烷、锗烷、锡烷。合成路线如下:a:R=Me,M=Si;b:R=Ph,M=Si;c:R=Ph,M=Ge;d:R=Ph,M=Sn1 实验部分1 1 仪器和试剂原料均为化学纯,所有溶剂都经过严格的无水、无氧处理,所有反应均与Schlenk操作线连接;质谱:HENLETTPACKARDMS5989;1HNMR:BRUKERAC80MHz;熔点测量:LEITZBIOMED… 相似文献
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Syntheses of several new 3,4‐dihydropyrimidinones (DHPMs) on sodium sulfate solid support have been reported. The microwave enhanced rapid synthesis of the title compounds yielded a good percentage of the DHPMs. The catalytic activity of indium triflate enables to prepare a wide range of DHPMs. Syntheses of 2‐hydroxyphenyl, 2‐hydroxy‐4‐methoxyphenyl pendant groups on DHPMs scaffold are advantages of the present method, which are rather prone towards cyclization and the presence of free hydroxyl groups on the phenyl ring is confirmed via D2O exchange study. The mechanism of the reaction is expected to proceed via absorption of substrates on the solid support followed by promotion of the reaction by In(OTf)3 coupled with microwave irradiation. 相似文献
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Self‐Assembly of a Giant Tetrahedral 3 d–4 f Single‐Molecule Magnet within a Polyoxometalate System 下载免费PDF全文
Dr. Masooma Ibrahim Dr. Valeriu Mereacre Dr. Nicolas Leblanc Prof. Wolfgang Wernsdorfer Dr. Christopher E. Anson Prof. Annie K. Powell 《Angewandte Chemie (International ed. in English)》2015,54(51):15574-15578
A giant tetrahedral heterometallic polyoxometalate (POM) [Dy30Co8Ge12W108O408(OH)42(OH2)30]56?, which shows single‐molecule magnet (SMM) behavior, is described. This hybrid contains the largest number of 4f ions of any polyoxometalate (POM) reported to date and is the first to incorporate two different 3d–4f and 4f coordination cluster assemblies within same POM framework. 相似文献
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A Bis‐Sulfonyl O,C,O Aryl Pincer Ligand and its Tin(II) Complex: Synthesis,Structural Studies,and DFT Calculations 下载免费PDF全文
Mohammad El Ezzi Romaric Lenk Dr. David Madec Dr. Jean‐Marc Sotiropoulos Sonia Mallet‐Ladeira Dr. Annie Castel 《Angewandte Chemie (International ed. in English)》2015,54(3):805-808
The efficiency of the deprotonated aryl bis‐sulfone [2,6‐{(p‐tolyl)SO2}2C6H3]? as an O,C,O‐coordinating pincer‐type ligand was described. The bis‐sulfone precursor was synthesized using a straightforward palladium‐catalyzed cross‐coupling reaction. As a result of directed ortho metalation (DoM) through sulfonyl groups, a selective lithiation of the aryl group was achieved and the corresponding carbanion was isolated and its structure determined by single‐crystal X‐ray diffraction analysis. A heteroleptic tin(II) complex has been prepared by a nucleophilic substitution reaction. Crystallographic analysis and DFT calculations indicate that the bis‐sulfonyl moiety acts as a new O,C,O‐coordinating pincer‐type ligand with intramolecular S?O coordination to a tin(II) center. The cis form with the two nonbonded oxygen atoms of the sulfonyl groups on the same side is preferentially obtained. 相似文献
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Stuiber S Wu G Nehrkorn J Dreiser J Lan Y Novitchi G Anson CE Unruh T Powell AK Waldmann O 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(33):9094-9106
The synthesis, crystal structure and magnetic characterisation by magnetisation and inelastic neutron scattering (INS) of a mixed-valent Mn(10) supertetrahedral aggregate [Mn(III)(6)Mn(II)(4)(μ(4)-O)(4)(μ(3)-N(3))(3)(μ(3)-Br)(Hmpt)(6)(Br)]Br(0.7)(N(3))(0.3)·2MeOH·3MeCN (1) (H(3)mpt=3-methylpentan-1,3,5-triol) is reported. The magnetic core of the molecule can be described as an octahedron of six S=2 Mn(III) ions with four faces, each capped by a S=5/2 Mn(II) ion such as to form the supertetrahedron. Unlike most related complexes, the molecular symmetry is slightly reduced from approximately T(d) to C(3). The magnetic data reveal a total spin of S=22 in the ground state due to ferromagnetic exchange couplings within the molecule. The combined INS and magnetic data permits the accurate determination of the exchange coupling constants. Two types are found. The couplings between the Mn(III) ions in the inner octahedron are characterised by J(a)=18.4(3) K, whereas the couplings between the apical Mn(II) ions to the neighbouring Mn(III) ions are given by J(b)=7.3(2) K. The significantly larger coupling strength J(a) as compared to J(b), and the near-T(d) symmetry have profound consequences on the energy spectrum, which are discussed and carefully analysed. In particular, the observed INS spectra can consistently be reproduced by a simplified model in which the inner octahedron is replaced by one large spin of length S(0)=12. This model provides intuitive insight into the structure of the magnetic spectrum. Additionally, the magnetic excitations at low temperature are analysed within the frame of ferromagnetic linear spin-wave theory, which permits an analytical calculation of the energy levels. For ferromagnetic clusters, a close analogy to the Hückel method of electronic structure calculation can be drawn, which allows one to grasp the results of the spin-wave theory or the magnetic excitation spectrum, respectively, in a chemical language. 相似文献