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991.
992.
993.
Summary Thin layers of lanthanum silicate have been used to study the chromatographic behaviour of 28 metal ions in aqueous and mixed
systems. As3+, Mo6+, Sb3+, Ti4+ and others can be easily separated from a number of inorganic ions. Fast ternary and binary separations have also been achieved
and various separations are discussed. It is shown that Alberti's relation is also obeyed by thin layers of lanthanum silicate.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
994.
Wei-Qiang Zhang Nikolay V.Tkachenko Lei Qiao Alexander I.Boldyrev Zhong-Ming Sun 《中国化学》2022,40(1):65-70
Polyarsenides containing coinage metals,[As7Cu(PPh3)]2-(1)and[M2As14]4-(M=Cu,2;Ag,3),were synthesized by reactions of the nominal composition K3As7 with Group 11 metal complexes.The possible intermediate,cluster 1,was isolated from the solution phase through subtle changes in reaction conditions in the formation process of complex 2.Hence,we establish the pathway of the bimetallic bridged clusters[Cu2As14]4-by the oxidation of the[As7Cu(PPh3)]2-.Quantum chemical calculations reveal the presence of metallophilic interaction in clusters 2 and 3. 相似文献
995.
利用标记药物布洛芬及保泰松研究萘啶酸与血清白蛋白的结合作用 总被引:2,自引:0,他引:2
血清白蛋白与萘啶酸的结合,可以猝灭萘啶酸-铽螯合体系的特征荧光,保泰松(Phenylbutazone)及布洛芬(Ibuprofen)等药物在白蛋白的特定结合位置与其具有较强的结合作用,因此,可用作白蛋白分子结合位置的标记物。本文以保泰松或布洛芬作标记物,探讨了牛血清白蛋白及人血清白蛋白对萘啶酸-铽螯合体系特征荧光的不同影响方式,并根据蛋白结合位上药物的置换作用确定了萘啶酸在牛血清白蛋白分子上的结合位置。 相似文献
996.
997.
Summary The 2-benzoylbenzoic acid series was investigated by reversed-phase, high-performance, thin-layer and column chromatography using various alkylammonium salts and di(2-ethylhexyl)orthophosphoric acid as polar associating reagents. The effects of the individual substituents on retention were quantified by log k and RM values. The compounds investigated differing in molecular structure (hydrophilic and hydrophobic substituents) commonly occurring groups in drugs and biologically active substances provide information on molecular interaction in these ion-pair systems. The combined effects on retention of organic modifier and ion-pair reagent concentration were investigated. 相似文献
998.
酶是生物催化剂,在数以千计的酶中,第一大类以烟酰胺腺嘌呤核苷酸(NAD/NADH)为辅酶的多种氧化-还原酶需要金属离子作为辅助因子而发生独特的催化功能。其中含锌的醇脱氨酶(ADH)是目前研究得最多的一种。本文用电化学分析法研究稀土离子对乳酸脱氢酶(LDH)和谷氨酸脱氢酶(GDH)两体系的作用时也探讨了Zn2+在此两体系中的作用。结果指出在LDH体系中不需要 Zn2+;在 GDH(牛肝中提取)体系中, Zn2+是一种强抑制剂,Eu3+可以缓解它的抑制作用,但是在黄瓜根系提取的粗GDH体系中,Zn2+必需存在于反介质中起激活酶的催化作用。 相似文献
999.
The interactions of lanthanide ions (Ln3+) with bovine serum albumin (BSA) under mimetic physiological conditions (310.15 K, pH 6.7, 0.1MNaCl) were studied by microcalorimetry.
For the first time, based on Two Sets of Independent Sites Model, molar enthalpies (Δr
H
m1, Δr
H
m2) and coordination number (n
1, n
2) of the two sets of binding sites with different affinity were obtained directly from the microcalorimetric results. It was
shown that the interactions are endothermic and entropy-driving processes. By combining with fluorescence spectroscopy, other
thermodynamic parameters (Δr
G
m1, Δr
S
m1) were determined for high-affinity specific sites. 相似文献
1000.
Tachikawa T Yoshida A Tojo S Sugimoto A Fujitsuka M Majima T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(21):5345-5353
The TiO2 photocatalytic one-electron oxidation mechanism of aromatic sulfides with a methylene bridging group (-(CH2)n-, n=0-4) between the 4-(methylthio)phenyl chromophore and the carboxylate binding group on the surface of a TiO2 powder slurried in acetonitrile (MeCN) has been investigated by time-resolved diffuse reflectance (TDR) spectroscopy. The electronic coupling element (H(DA)) between the hole donor and acceptor, which was estimated from the spectroscopic characteristics of the charge transfer (CT) complexes of the substrates (S) and the TiO2 surface, exhibited an exponential decline with the increasing of the methylene number of S. The determined decay factor (beta) of 9 nm(-1) also supports the fact that the 4-(methylthio)phenyl chromophore is separated from the TiO2 surface. The efficiency of the one-electron oxidation of S adsorbed on the TiO2 surface, which was determined from the relationship between the amount of adsorbates and the concentration of the generated radical cations, significantly depended on the H(DA) value, but not on the oxidation potential of S determined in homogeneous solution. 相似文献