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141.
Sunitha V. Kishore Kumar A. Shankar B. Anil Kumar A. Krishna T. M. Lincoln Ch. A. Pochampalli J. 《Russian Journal of General Chemistry》2017,87(2):322-330
In the present study, a series of novel {6-[(1H-1,2,3-triazol-4-yl)methoxy]-3-methylbenzofuran-2-yl}(phenyl)methanones (7a–7o) have been synthesized using click chemistry approach. The structures of all newly synthesized compounds were characterized by FT-IR, 1H and 13C NMR, and MASS spectral data. Most of products demonstrated high antimicrobial activity.
相似文献142.
Vinod K. Tiwari Archana Singh Hakkim A. Hussain Bhuwan B. Mishra Vyasji Tripathi 《Monatshefte für Chemie / Chemical Monthly》2007,138(7):653-658
Summary. A convenient and high yielding method for the synthesis of diverse dithiocarbamates having various substituents including
alkyl, aryl, heteroaryl, and alkylaryl at the thiol chain or at the amine chain or at both thiol and amine chains were developed
by the one-pot reaction of mercaptans, amines, and bis(benzotriazolyl)methanethione in presence of amidine base under mild
reaction conditions. 相似文献
143.
Dr. Lin He Dr. Kishore Natte Dr. Jabor Rabeah Dr. Christoph Taeschler Dr. Helfried Neumann Prof. Dr. Angelika Brückner Prof. Dr. Matthias Beller 《Angewandte Chemie (International ed. in English)》2015,54(14):4320-4324
Fluorinated organic compounds are gaining increasing interest for life science applications. The replacement of hydrogen in arenes or heteroarenes by a perfluoroalkyl group has a profound influence on the physical and biological properties of such building blocks. Here, an operationally simple protocol for the direct C? H perfluoroalkylation of (hetero)arenes with RfI or RfBr has been developed, using a robust supported platinum catalyst. The ready availability of the starting materials, the excellent substrate tolerance, and the reusability of the catalyst make this method attractive for the synthesis of a variety of perfluoroalkyl‐substituted aromatic compounds. Preliminary mechanistic studies revealed the formation of radicals to be crucial in the reaction system. 相似文献
144.
Archana Srivastava N.K. Gaur Nupinderjeet Kaur R.K. Singh 《Journal of magnetism and magnetic materials》2008
We have investigated the thermodynamic properties of perovskite manganite LaMnO3, the parent compound of colossal magnetoresistive manganites, with the Ca2+ doping at the A-site. As strong electron-phonon interactions are present in these compounds, the lattice part of the specific heat deserves proper attention. We have described the temperature dependence of the lattice contribution to the specific heat at constant volume (Cv(lattice)) of La1−xCaxMnO3 (x=0.125, 0.175, 0.25, 0.35, 0.50, 0.67, 0.75) as a function of temperature (1 K–20 K) by means of a rigid ion model (RIM).The trends of specific heat variations with temperature are almost similar at all the composition. The Debye temperatures obtained from the lattice contributions are found to be in somewhat closer agreement with the experimental data. The specific heat values revealed by using RIM are in closer agreement with the available experimental data, particularly at low temperatures for some concentrations (x) of La1−xCaxMnO3. The theoretical results at higher temperatures can be improved by including the effects of the charge ordering, van der Waals attraction and anharmonicity in the framework of RIM. 相似文献
145.
V.P. Rama Kishore Putta Raghuram Gujjarappa Nagaraju Vodnala Richa Gupta Prasad P. Pujar Chandi C. Malakar 《Tetrahedron letters》2018,59(10):904-908
The first organocatalytic approach towards synthesis of rarely explored 1,2,4-selenadiazole and thiadiazole scaffolds have been devised using corresponding carboxamides as substrates. The transformations were realized using two distinct conditions in the presence of catalytic vitamin B3 or thiourea under aerobic conditions. Developed methods overcome the associated limitations of previous reported approaches and the desired products were obtained in high yields and selectivity without the formation of toxic side-products. 相似文献
146.
Experimental Mechanics - An experimental investigation is conducted to study the mechanics of underwater implosion of cylindrical bonded sandwich composite shells. Sandwich structures comprised of... 相似文献
147.
In recent years, angular and linear phenoxazines and their derivatives and polymers have attracted much attention due to their great pharmacological and industrial utility. So it becomes imperative to review the work done in this area more frequently. Therefore, various synthetic routes for phenoxazines are reviewed here comprehensively. 相似文献
148.
Partial Molar Volumes of Some of α-Amino Acids in Binary Aqueous Solutions of MgSO4·7H2O at 298.15 K
The apparent molar volume, V
o
φ, 2, of glycine, alanine, α-amino-n-butyric acid, valine and leucine have been determined in aqueous solutions of 0.25, 0.5 and 1.0 mol⋅dm−3 magnesium sulfate, and the partial specific volume from density measurements at 298.15 K. These data have been used to calculate the infinite dilution apparent molar volume, V
o
2,m
, group contribution of amino acids and partial molar volume of transfer, Δtr
V
2,m
o, from water to aqueous magnesium sulfate solutions. The linear correlation of V
2,m
o for a homologous series of amino acids has been utilized to calculate the contributions of charged end groups (NH3
+, COO−), CH2 - groups and other alkyl chains of amino acids to V
2,m
o. The results for Δtr
V
2,m
o of amino acids from water to aqueous magnesium sulfate solutions have been interpreted in terms of ion-ion, ion-polar, hydrophilic-hydrophilic and hydrophobic-hydrophobic group interactions. The values of the standard partial molar volume of transfer for the amino acids with different hydrophobic contents, from water to aqueous MgSO4 are in general positive, indicating the predominance of the interactions of zwitterionic/hydrophilic groups of amino acids with ions of the salt. The hydration number decreases with increasing concentration of salt. The number of water molecules hydrated to amino acids decreases, further strengthening the predominance of ionic/hydrophilic interactions in this system. 相似文献
149.
G. R. Dey D. B. Naik K. Kishore P. N. Moorthy 《Journal of Radioanalytical and Nuclear Chemistry》1992,163(2):391-400
Rate constants for the reaction of the primary species of water radiolysis, viz. e
aq'
–
, H and OH, with picolinic acid have been determined at various pHs. The semi-reduced species exhibits max at 305 and 350 nm. It is a strong reductant and has two pKa values of 1 and 5.7. The OH adduct of this compound also exhibits two pKa s at 2.1 and 5.2. H-atom reaction with picolinic acid gives rise to a mixture of species. 相似文献
150.
The role of thermal decomposition of the binder and the oxidiser in the thermal decomposition, ageing and combustion of composite solid-propellants has been investigated. The present study shows that the burning rate and ageing of polystyrene and ammonium perchlorate propellant are related to the thermal decomposition of the propellant itself and ammonium perchlorate. 相似文献