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11.
Karen Avetisyan Miroslav Pavlovi? 《Journal of Mathematical Analysis and Applications》2007,336(1):31-43
It is proved that the inequality δX(ε)?cεp, p?2, where δX is the modulus of convexity of X, is sufficient and necessary for the inequality
12.
Normanskaja Yu. V. Borisenko O. D. Beloborodov I. B. Avetisyan A. I. 《Doklady Mathematics》2022,106(3):487-487
Doklady Mathematics - An Erratum to this paper has been published: https://doi.org/10.1134/S1064562422340038 相似文献
13.
E. G. Mesropyan A. A. Avetisyan A. S. Galstyan 《Russian Journal of Organic Chemistry》2007,43(8):1176-1179
Synthesis was performed of substituted 2-propanols based on glycidyl phenyl and glycidyl allyl ethers, Also some acetic acid esters were prepared. 相似文献
14.
Fu Y Habtemariam A Basri AM Braddick D Clarkson GJ Sadler PJ 《Dalton transactions (Cambridge, England : 2003)》2011,40(40):10553-10562
We report the synthesis and characterisation of 32 half sandwich phenylazopyridine Os(II) arene complexes [Os(η(6)-arene)(phenylazopyridine)X](+) in which X is chloride or iodide, the arene is p-cymene or biphenyl and the pyridine and phenyl rings contain a variety of substituents (F, Cl, Br, I, CF(3), OH or NO(2)). Ten X-ray crystal structures have been determined. Cytotoxicity towards A2780 human ovarian cancer cells ranges from high potency at nanomolar concentrations to inactivity. In general the introduction of an electron-withdrawing group (e.g. F, Cl, Br or I) at specific positions on the pyridine ring significantly increases cytotoxic activity and aqueous solubility. Changing the arene from p-cymene to biphenyl and the monodentate ligand X from chloride to iodide also increases the activity significantly. Activation by hydrolysis and DNA binding appears not to be the major mechanism of action since both the highly active complex [Os(η(6)-bip)(2-F-azpy)I]PF(6) (9) and the moderately active complex [Os(η(6)-bip)(3-Cl-azpy)I]PF(6) (23) are very stable and inert towards aquation. Studies of octanol-water partition coefficients (log P) and subcellular distributions of osmium in A2780 human ovarian cancer cells suggested that cell uptake and targeting to cellular organelles play important roles in determining activity. Although complex 9 induced the production of reactive oxygen species (ROS) in A2780 cells, the ROS level did not appear to play a role in the mechanism of anticancer activity. This class of organometallic osmium complexes has new and unusual features worthy of further exploration for the design of novel anticancer drugs. 相似文献
15.
A. G. Panosyan G. M. Avetisyan M. N. Nikishchenko V. A. Mnatsakanyan 《Chemistry of Natural Compounds》1980,16(6):554-557
The lipid composition of the roots ofBryonia alba (Cucurbitaceae) have been studied: It consists of fractions of 3-acyloxy-24-alkyl(alkenyl)-cholest-7-enes (I), triacylglycerols (II), 1,2-diacyl-3-monoglycopyranosyl-sn-glycerols (III), 1,2-diacyl-3-diglycopyranosyl-sn-glycerols (IV), 1,3-bis(3-sn-phosphatidyl)glycerols (V), 3-sn-phosphatidylethanolamines (VI), 3-sn-phosphatidylcholines (VII), and methyl esters of fatty acids (VIII). The amount of unsaturated fatty acids in the lipid fractions (I–VIII) is 60–94%, the main component being linolenic acid. 相似文献
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A series of dendrimer-encapsulated poly(phenyleneethynylene)s 4~6 were Synthesize d. The light-harvesting antenna functions of dendrimer frameworks together with the blue-light emitting activities of 4~6 were highlighted. 相似文献
18.
K Kitagawa C Aida H Fujiwara T Yagami S Futaki M Kogire J Ida K Inoue 《The Journal of organic chemistry》2001,66(1):1-10
Chemical synthesis of tyrosine O-sulfated peptides is still a laborious task for peptide chemists because of the intrinsic acid-lability of the sulfate moiety. An efficient cleavage/deprotection procedure without loss of the sulfate is the critical difficulty remaining to be solved for fluoren-9-ylmethoxycarbonyl (Fmoc)-based solid-phase synthesis of sulfated peptides. To overcome the difficulty, TFA-mediated solvolysis rates of a tyrosine O-sulfate [Tyr(SO3H)] residue and two protecting groups, tBu for the hydroxyl group of Ser and 2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonyl (Pbf) for the guanidino group of Arg, were examined in detail. The desulfation obeyed first-order kinetics with a large entropy (59.6 J.K-1.mol-1) and enthalpy (110.5 kJ.mol-1) of activation. These values substantiated that the desulfation rate of the rigidly solvated Tyr(SO3H) residue was strongly temperature-dependent. By contrast, the SN1-type deprotections were less temperature-dependent and proceeded smoothly in TFA of a high ionizing power. Based on the large rate difference between the desulfation and the SN1-type deprotections in cold TFA, an efficient deprotection protocol for the sulfated peptides was developed. Our synthetic strategy for Tyr(SO3H)-containing peptides with this effective deprotection protocol is as follows: (i) a sulfated peptide chain is directly constructed on 2-chlorotrityl resin with Fmoc-based solid-phase chemistry using Fmoc-Tyr(SO3Na)-OH as a building block; (ii) the protected peptide-resin is treated with 90% aqueous TFA at 0 degree C for an appropriate period of time for the cleavage and deprotection. Human cholecystokinin (CCK)-12, mini gastrin-II (14 residues), and little gastrin-II (17 residues) were synthesized with this method in 26-38% yields without any difficulties. This method was further applied to the stepwise synthesis of human big gastrin-II (34 residues), CCK-33 and -39. Despite the prolonged acid treatment (15-18 h at 0 degree C), the ratios of the desulfated peptides were less than 15%, and the pure sulfated peptides were obtained in around 10% yields. 相似文献
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