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91.
A. L. Gushchin K. A. Kovalenko M. N. Sokolov D. Yu. Naumov E. V. Peresypkina A. V. Virovets V. P. Fedin 《Russian Chemical Bulletin》2007,56(9):1707-1711
The reactions of the oxalate complexes [M3Q7(C2O4)3]2− (M = Mo or W; Q = S or Se) with MnII, CoII, NiII, and CuII aqua and ethylenediamine complexes in aqueous and aqueous ethanolic solutions were studied. The previously unknown heterometallic
complexes [Mo3Se7(C2O4)3Ni(H2O)5]·3.5H2O (1) and K3{[Cu(en)2H2O]([Mo3S7(ox)3]2Br)}·5.5H2O (2) were synthesized. In these complexes, the oxalate clusters serve as monodentate ligands. The K(H2en)2[W3S7(C2O4)3]2Br·4H2O salt (3) was isolated from solutions containing CoII, NiII, or CuII aqua complexes and ethylenediamine. The reaction of [Mo3Se7(C2O4)3]2− with HBr produced the bromide complex [Mo3Se7Br6]2−, which was isolated as (Bu4N)2[Mo3Se7Br6] (4). Complexes 1–3 were characterized by X-ray diffraction, IR spectra, and elemental analysis. The formation of 4 was detected by electrospray mass spectrometry.
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1645–1649, September, 2007. 相似文献
92.
Yu. M. Basalaev Yu. N. Zhuravlev E. B. Kitova A. S. Poplavnoi 《Journal of Structural Chemistry》2007,48(6):1001-1005
First principle calculations were performed for the first time to study the electronic structure of LiGaTe2, LiInTe2, and LiInSe2 chalcogenides with a chalcopyrite structure. Peculiarities of chemical bonding are discussed and electron density and difference density maps are constructed for crystals and sublattices. Major information about chemical bonding in crystals is conveyed by the difference density. The chemical bond in chalcogenides is a donor-acceptor bond. 相似文献
93.
In this review article the synthesis of iron chalcogenides using single source precursors is discussed. The effect on morphology and phase of iron chalcogenides formed is studied by varying single source precursors, reaction temperature, reaction time, surfactants and their concentration. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
94.
[FeFe]‐Hydrogenase with Chalcogenide Substitutions at the H‐Cluster Maintains Full H2 Evolution Activity 下载免费PDF全文
Dr. Jens Noth Dr. Julian Esselborn Dr. Jörn Güldenhaupt Annika Brünje Dr. Anne Sawyer Dr. Ulf‐Peter Apfel Prof. Klaus Gerwert Prof. Eckhard Hofmann Dr. Martin Winkler Prof. Thomas Happe 《Angewandte Chemie (International ed. in English)》2016,55(29):8396-8400
The [FeFe]‐hydrogenase HYDA1 from Chlamydomonas reinhardtii is particularly amenable to biochemical and biophysical characterization because the H‐cluster in the active site is the only inorganic cofactor present. Herein, we present the complete chemical incorporation of the H‐cluster into the HYDA1‐apoprotein scaffold and, furthermore, the successful replacement of sulfur in the native [4FeH] cluster with selenium. The crystal structure of the reconstituted pre‐mature HYDA1[4Fe4Se]H protein was determined, and a catalytically intact artificial H‐cluster variant was generated upon in vitro maturation. Full hydrogen evolution activity as well as native‐like composition and behavior of the redesigned enzyme were verified through kinetic assays, FTIR spectroscopy, and X‐ray structure analysis. These findings reveal that even a bioinorganic active site with exceptional complexity can exhibit a surprising level of compositional plasticity. 相似文献
95.
手性含硫化合物在药物化学和不对称合成领域中应用广泛,发展这类化合物的新合成方法是有机合成化学的重要任务.烯烃的不对称亲电硫化反应为手性含硫化合物的合成提供了一条方便的途径,通过这种方式不仅可以在烯烃母体分子上引入一个含硫基团,同时也能够引入另外一个重要的官能团.我们课题组设计、合成了一系列手性双官能硒醚/硫醚催化剂,并... 相似文献
96.
K. Stwe 《无机化学与普通化学杂志》1996,622(8):1419-1422
Contributions to the Crystal Chemistry of Uranium Tellurides. I. The Crystal Structure of α-Uranium Tritelluride Single crystals of the title compound up to a size of 8 mm were available via chemical transport reactions with TeBr4 as transporting agent starting from the elements. The analysis by atomic emission spectrometry gave UTe3.0(1). By X-ray single crystal structure analysis we found that UTe3 crystallizes monoclinic (space group P 21/m, Z = 2) with a = 609.7(1) pm, b = 422.06(4) pm, c = 1031.2(1) pm and β = 97.87(1)º in the ZrSe3-structure type. The layer structure is built up by bicapped trigonal prisms. 相似文献
97.
A novel one-step electrochemical method for the preparation of capping-free cadmium sulfide nanoparticles is described. With
gold as the working electrode, capping-free CdS nanoparticles are synthesized very conveniently at 70°C in the ethylene glycol
(EG) solution of elementary sulfur, cadmium salt, and supporting electrolyte at −0.1 V. By carefully selecting the reductive
potential, elementary sulfur is reduced while the reduction of Cd2+ is blocked by the formation of a sulfur monolayer on the gold electrode surface. The produced S2− reacts with cadmium cations in the solution to produce CdS. In this method, magnetic stirring can effectively prevent the
deposition of CdS on the electrode surface. XRD analysis indicates that the product is pure cubic-phase CdS. The size and
morphology of the particles are studied by TEM.
Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 9, pp. 1060–1064.
The text was submitted by the authors in English. 相似文献
98.
A. A. Soliman 《Journal of Thermal Analysis and Calorimetry》2007,89(2):389-392
A brief derivation of the Kissinger’s equation for analysis of experimental data of non-isothermal glass transition peaks
based on the free volume model is given. This equation was applied successfully to Cu0.3(SSe20)0.7 chalcogenide glass for different heating rates. For granted this model, the obtained glass transition activation energy,
E
g must be constant throughout the whole glass transition temperature range. This required that T
g to be determined for three characteristic temperature points for each DSC curve. 相似文献
99.
K. Stwe 《无机化学与普通化学杂志》1996,622(8):1423-1427
Contributions to the Crystal Chemistry of Uranium Tellurides. II. The Crystal Structure of Diuranium Pentatelluride U2Te5 Via chemical transport reactions with TeBr4 as transporting agent single crystals of the title compound up to a size of 5 mm were available from the elements. The analysis by atomic emission spectrometry gave UTe2.52(4). By X-ray single crystal structure analysis we found that U2Te5 crystallizes monoclinic (space group C2/m, Z = 4) with a = 3443.3(5) pm, b = 418.65(3) pm, c = 607.97(6) pm and β = 95.35(1)º in a new structure type. The layer structure is built up by bicapped trigonal prisms, one half as isolated building units, the other connected via faces as fourfold capped biprisms. A structural relationship of diuranium pentatelluride to the adjacent phases in the phase diagram U? Te can be expressed by the formulation as UTe2 · UTe3. 相似文献
100.
M. I. Avramov D. M. Petrović S. R. Lukić S. J. Skuban 《Journal of Thermal Analysis and Calorimetry》1995,44(5):1203-1209
Results of thermal investigations of the amorphous five-component chalcogenide system Ge20As14(SexS1?x)52I14 are presented. Differential thermal analysis (DTA), derivative differential thermal analysis (DDTA), and dilatometry were employed to determine the temperatures of softening and partial crystallization of the samples. Thermal treatment of the samples at 1000°C and recording of the corresponding thermogravimetric (TG) and derivative thermogravimetric (DTG) curves allowed an elucidation of the full mechanism of their decomposition, which proceeds via seven characteristic phase transitions. 相似文献