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961.
Simple, economical, and environmentally friendly method to synthesize 2-alkylbenzimidazoles was developed by modifying the conventional method between o-phenylenediamine and aldehyde. 相似文献
962.
963.
Structure‐Based Approach To Improve a Small‐Molecule Inhibitor by the Use of a Competitive Peptide Ligand 下载免费PDF全文
Dr. Katsuki Ono Dr. Koh Takeuchi Hiroshi Ueda Yasuhiro Morita Dr. Ryuji Tanimura Prof. Ichio Shimada Prof. Hideo Takahashi 《Angewandte Chemie (International ed. in English)》2014,53(10):2597-2601
Structural information about the target–compound complex is invaluable in the early stage of drug discovery. In particular, it is important to know into which part of the initial compound additional interaction sites could be introduced to improve its affinity. Herein, we demonstrate that the affinity of a small‐molecule inhibitor for its target protein could be successfully improved by the constructive introduction of the interaction mode of a competitive peptide. The strategy involved the discrimination of overlapping and non‐overlapping peptide–compound pharmacophores by the use of a ligand‐based NMR spectroscopic approach, INPHARMA. The obtained results enabled the design of a new compound with improved affinity for the platelet receptor glycoprotein VI (GPVI). The approach proposed herein efficiently combines the advantages of compounds and peptides for the development of higher‐affinity druglike ligands. 相似文献
964.
Photothermal Conversion of CO2 into CH4 with H2 over Group VIII Nanocatalysts: An Alternative Approach for Solar Fuel Production 下载免费PDF全文
Xianguang Meng Dr. Tao Wang Dr. Lequan Liu Dr. Shuxin Ouyang Dr. Peng Li Huilin Hu Dr. Tetsuya Kako Dr. Hideo Iwai Dr. Akihiro Tanaka Prof. Jinhua Ye 《Angewandte Chemie (International ed. in English)》2014,53(43):11478-11482
The photothermal conversion of CO2 provides a straightforward and effective method for the highly efficient production of solar fuels with high solar‐light utilization efficiency. This is due to several crucial features of the Group VIII nanocatalysts, including effective energy utilization over the whole range of the solar spectrum, excellent photothermal performance, and unique activation abilities. Photothermal CO2 reaction rates (mol h?1 g?1) that are several orders of magnitude larger than those obtained with photocatalytic methods (μmol h?1 g?1) were thus achieved. It is proposed that the overall water‐based CO2 conversion process can be achieved by combining light‐driven H2 production from water and photothermal CO2 conversion with H2. More generally, this work suggests that traditional catalysts that are characterized by intense photoabsorption will find new applications in photo‐induced green‐chemistry processes. 相似文献
965.
Chemoselective Hydrogenation of Functionalized Nitroarenes and Imines by Using Carbon Nanofiber‐Supported Iridium Nanoparticles 下载免费PDF全文
Prof. Dr. Yukihiro Motoyama Masahiro Taguchi Dr. Nelfa Desmira Prof. Dr. Seong‐Ho Yoon Prof. Dr. Isao Mochida Prof. Dr. Hideo Nagashima 《化学:亚洲杂志》2014,9(1):71-74
The reaction of three types of carbon nanofibers (CNFs; platelet: CNF‐P, tubular: CNF‐T, herringbone: CNF‐H) with Ir4(CO)12 in mesitylene at 165 °C provided the corresponding CNF‐supported iridium nanoparticles, Ir/CNFs (Ir content=2.3–2.6 wt. %). Transmission electron microscopy (TEM) studies of these Ir/CNF samples revealed that size‐controlled Ir nanoparticles (average particle size of 1.1–1.5 nm) existed on the CNFs. Among the three Ir/CNF samples, Ir/CNF‐T showed an excellent catalytic activity and chemoselectivity towards hydrogenation of functionalized nitroarenes and imines; the corresponding aniline derivatives were obtained with high turnover numbers at ambient temperature under 10 atm of H2, and the catalyst is reusable. Ir/CNF‐T was also effective for the reductive N‐alkylation of anilines with carbonyl compounds. 相似文献
966.
Tetsushi Kijima Masakazu Nishida Haruhiko Fukaya Masato Yoshida Hideo Sawada 《先进技术聚合物》2014,25(3):258-264
Aromatic ketones such as 4′‐methoxyacetophenone (MAP), acetophenone (AP), 4‐acetylbiphenyl (ABP), and 2‐acetyl‐6‐methoxynapthalene (AMN) interacted with fluoroalkyl end‐capped 2‐acrylamido‐2‐methylpropanesulfonic acid oligomer [RF‐(AMPS)n‐RF] at 80°C for 3 h to give the corresponding fluorinated oligomer/aromatic ketones composites. In these composites, the RF‐(AMPS)n‐RF/MAP and /AP composites were found to give the homoaldol condensation products of MAP and AP, respectively. In contrast, the corresponding non‐fluorinated AMPS oligomer/MAP and sulfuric acid/MAP composites could not give the homoaldol product at all under similar conditions. This suggests that the RF‐(AMPS)n‐RF oligomer could provide the suitable fluorinated oligomeric gel newtwok cores to interact with MAP or AP as a guest molecule, and the homoaldol condensation of encapsulated MAP and AP should proceed smoothly in the fluorinated oligomeric gel network cores. The RF‐(AMPS)n‐RF/ABP and /AMN composites could not give the homoaldol products at all under similar conditions, indicating that the more bulky aromotic ketones than MAP or AP are not likely to be encapasulated as guest molecules into the fluorinated AMPS oligomeric gel netwok cores. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
967.
Hirokazu Takashima Ryotaro Arita Kazuhiko Kuroki Hideo Aoki 《Physica C: Superconductivity and its Applications》2010
While the functional renormalization group is a powerful theoretical method, the static approximation has been usually adopted in which the Matsubara frequency dependence of vertex functions is ignored. We propose a formalism beyond the static approximation with an efficient parameterization in the Matsubara frequency space for the vertex functions to incorporate the self-energy. 相似文献
968.
969.
2-Fluoro-3-phenyl-allyltrimethylsilane, prepared from β-fluorinated allylic acetate via a π-allylpalladium intermediate, reacted with various aldehydes and acetals in the presence of TiCl4 to afford the corresponding homoallyl alcohols and homoallyl ethers, respectively, in good to moderate yields. 相似文献
970.
Keiko Yasumatsu Tadahiro Ohkuri Keisuke Sanematsu Noriatsu Shigemura Hideo Katsukawa Noritaka Sako Yuzo Ninomiya 《BMC neuroscience》2009,10(1):152