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91.
Kinetic study on the cleavage of N‐phenylphthalimide (NPhPT) in the presence of 0.05 M NH2NH2 and mixed H2O‐CH3CN solvents reveals the occurrence of reaction scheme where A, B, C, C1, An, E, and F represent NPhPT, o‐CO?2C6H4CONHC6H5, o‐CONHNH2C6H4‐ CONHC6H5, N‐aminophthalimide, aniline, o‐CO?2C6H4CONHNH2, and o‐CONHNH2C6H4‐CONHNH2, respectively. But, in the presence of either nonbuffered ?0.20 M NH2NH2 hydrazine buffer of pH ~7.30–8.26 with total buffer concentration ([Buf]T) of >0.02 M, further conversion of F to 2,3‐dihydrophthalazine‐1,4‐dione (DHPD) has been detected depending upon the length of the reaction time (t), the values of [Buf]T, and pH. It has been shown that the rate of conversion of C1 to F is much faster than that of C to C1 which is much faster than that of F to DHPD. The reaction step A → C involves general base (GB) catalysis, while step C → C1 seems to involve specific base–general acid (GA) and GB‐GB catalysis. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 37: 147–161, 2005 相似文献
92.
N-(α-Benzotriazolylalkyl)arylacetamides, readily available from an arylacetamide, an aldehyde and benzotriazole, undergo intramolecular cyclization under acidic conditions to give 1-aryl-1,4-dihydro-3(2H)-isoquinolinones in good to excellent yields. Similarly, 2-(benzotriazol-1-yl)-2-(o-hydroxyphenyl)ethanols, obtained by lithiation of 2-(benzotriazol-1-ylmethyl)phenols followed by quenching with aldehydes or ketones, eliminate a molecule of water and a molecule of benzotriazole yielding 2-substituted and 2,3-disubstituted benzofurans. 相似文献
93.
Bai JZ Bardon O Blum I Breakstone A Burnett T Chen GP Chen HF Chen J Chen SJ Chen SM Chen Y Chen YB Chen YQ Cheng BS Cowan RF Cui HC Cui XZ Ding HL Du ZZ Dunwoodie W Fan XL Fang J Fero M Gao CS Gao ML Gao SQ Gao WX Gratton P Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y Harris FA Hatanaka M He J He KR He M Hitlin DG Hu GY Hu HB Hu T Hu XQ Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jin Y Jones L Kang SH Kelsey MH Kim BK Lai YF Lan HB Lang PF Lankford A Li F Li J Li PQ Li Q Li RB 《Physical review D: Particles and fields》1995,52(7):3781-3784
94.
F. M. Lanças M. A. Barbirato N. R. Antoniosi filho 《Journal of Radioanalytical and Nuclear Chemistry》1995,189(2):319-323
Three nitrogenated fungicides (Bayfidan, Bayleton and Baycor) were irradiated with -rays from a60Co source with the products being analyzed by high resolution gas chromatography (HRGC). Within the dose range studied (5 to 640 kGy), all three compounds were found to be stable. 相似文献
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Aihua Zhang Kun Liu Lan Li Siyu Ma Zonghe Li 《International journal of quantum chemistry》2005,104(3):373-378
The ring‐closing reaction of 5′‐adenosine monophosphate (5′‐AMP) to generate cyclic 3′, 5′‐adenosine monophosphate (cAMP) and H2O was theoretically investigated at the B3LYP/6‐31G**level. It was found that the ring‐closing reaction of 5′‐AMP may proceed in a synchronous way or in a stepwise way. For the latter, the reaction is a multichannel elimination reaction including inner H transfer. The potential energy surface of Path 3 is lowest in all the ring‐closing reaction paths. In addition, H shuttling reaction with the participation of a water molecule to act as a shuttle were also studied at the same level. The calculations indicate that the participation of a water molecule facilitates hydrogen transfer reaction. Our present calculations rationalized all the possible reaction channels. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
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The immobilization of anti-IgG on Au-colloid modified gold electrodes has been investigated. A cleaned gold electrode was first immersed in a mercaptoethylamine (AET) solution, and then gold nanoparticles were chemisorbed onto the thiol groups of the mercaptoethylamine. Finally, anti-IgG was adsorbed onto the surface of the gold nanoparticles. Potentiometric immunosensor, cyclic voltammetry, and electrochemical impedance techniques were used to investigate the immobilization of anti-IgG on Au colloids. In the impedance spectroscopic study, an obvious difference of the electron transfer resistance between the Au-colloid modified electrode and the bare gold electrode was observed. The cyclic voltammogram tends to be more irreversible with increased anti-IgG concentration. Using the potentiometric immunosensor, the proposed technique is based on that the specific agglutination of antibody-coated gold nanoparticles, averaging 16 nm in diameter, in the presence of the corresponding antigen causes a potential change that is monitored by a potentiometry. It is found that the developed immunoagglutination assay system is sensitive to the concentration of IgG antigen as low as 12 ng mL(-1). Experimental results showed that the developed technique is in satisfactory agreement with the ELISA method, and that gold nanoparticles can be used as a biocompatible matrix for antibody or antigen immobilization. 相似文献