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101.
Tadashi Miyasaka Hiromichi Tanaka Kazue Satoh Mie Imahashi Kentaro Yamaguchi Yoichi Iitaka 《Journal of heterocyclic chemistry》1987,24(3):873-875
A highly efficient intramolecular nitrene insertion was observed upon irradiation of 6-azidouridine derivatives. The N6,2′-cyclo structure of the product was determined unequivocally by X-ray crystallography. 相似文献
102.
An Electron Dynamics Mechanism of Charge Separation in the Initial‐Stage Dynamics of Photoinduced Water Splitting in XMnWater (X=OH,OCaH) and Electron–Proton Acceptors 下载免费PDF全文
An electron dynamics mechanism of charge separation in the initial stage of excited‐state reactions of the class of X?Mn?OH2???A${ \to }$ X?Mn?OH???HA (X=OH or OCaH; A=N‐methylformamidine, guanidine, imidazole, or ammonia cluster) is reported. The dynamic effect of calcium doping is also revealed. This study provides a novel factor to be considered in designing efficient systems for photoinduced water splitting. 相似文献
103.
The authors describe the relationships between categories of B-branes in different phases of the non-Abelian gauged linear sigma model.The relationship is described explicitly for the model proposed by Hori and Tong with non-Abelian gauge group that connects two non-birational Calabi-Yau varieties studied by Rφdland.A grade restriction rule for this model is derived using the hemisphere partition function and it is used to map B-type D-branes between the two Calabi-Yau varieties. 相似文献
104.
Tutorial review: to achieve molecule-based spintronic devices, an organic conducting magnet that exhibits both conductivity and magnetism in a cooperative manner must be constructed. As a building block for such new materials, a spin-polarized donor radical, which serves as a molecular "spin-filter" in its singly oxidized state, was designed and synthesized. The resistivity of ion radical salts of selenium-substituted, tetrathiafulvalene-based spin-polarized donor radicals decreased substantially in the presence of a magnetic field, thus indicating cooperative conductivity and magnetism. 相似文献
105.
Yamada Y Hozumi K Nomizu M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(38):10500-10508
Cell-adhesive peptides derived from extracellular matrix (ECM) proteins are potential candidates for incorporating cell-binding activities into materials for tissue engineering. We have identified a number of cell adhesive peptides from laminins, which are major components of basement membrane ECM. Our goal is the development of synthetic basement membranes using the peptides on scaffolds. We review peptide–polysaccharide complexes, which were prepared by conjugation of the peptides to chitosan and alginate, and the biological activities of the resulting matrices. The peptide–polysaccharide matrices can also be used as a biomaterial for cell transplantation. These studies suggest that the peptide–polysaccharide complexes have the potential to mimic the multifunctional basement membrane and may be useful for tissue engineering. 相似文献
106.
Jiang HL Liu B Lan YQ Kuratani K Akita T Shioyama H Zong F Xu Q 《Journal of the American Chemical Society》2011,133(31):11854-11857
In this work, with a zeolite-type metal-organic framework as both a precursor and a template and furfuryl alcohol as a second precursor, nanoporous carbon material has been prepared with an unexpectedly high surface area (3405 m(2)/g, BET method) and considerable hydrogen storage capacity (2.77 wt % at 77 K and 1 atm) as well as good electrochemical properties as an electrode material for electric double layer capacitors. The pore structure and surface area of the resultant carbon materials can be tuned simply by changing the calcination temperature. 相似文献
107.
Kurono N Ohtsuga K Wakabayashi M Kondo T Ooka H Ohkuma T 《The Journal of organic chemistry》2011,76(24):10312-10318
Kinetic resolution of sterically hindered racemic α-tert-alkyl-α-hydroxy esters is performed by enantiomer-selective carbamoylation with the t-Bu-Box-Cu(II) catalyst (Box = bis(oxazoline)). The reaction with 0.5 equiv of n-C(3)H(7)NCO is carried out with a substrate-to-catalyst molar ratio of 500-5000 at -20 to 25 °C. The high enantiomer-discrimination ability of the catalyst achieves an excellent stereoselectivity factor (s = k(fast)/k(slow)) of 261 in the best case. A catalytic cycle for this reaction is proposed. 相似文献
108.
Size selective inclusion of organic molecules into pillared carbons accompanied by large interlayer expansions was observed for the first time. In order to achieve this, the distance between two adjacent pillars should be between 0.36 and 0.40 nm and they should align in the same direction. 相似文献
109.
110.