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Journal of Thermal Analysis and Calorimetry - It is well known that cement production is not neutral for natural environment among others due to high CO2 emission. Different strategies of... 相似文献
94.
Rose Mary Michell Iwona Blaszczyk‐Lezak Carmen Mijangos Alejandro J. Müller 《Journal of Polymer Science.Polymer Physics》2014,52(18):1179-1194
In this article, a review of recent literature on confined crystallization within nanoporous anodic aluminum oxide (AAO) templates is presented. For almost all infiltrated polymeric materials, crystal orientation within the nanopores is a function of pore diameter. Tc and Tm usually decrease and are a function of pore size. When no pore interconnection remains, the crystallization occur at large supercoolings in heterogeneity free environments. Hence, the nucleation mechanism changes from heterogeneous to surface or homogeneous nucleation. The crystallization kinetics of infiltrated polymers should be close to first order, since in confined environments nucleation is the determining step of the overall crystallization and Avrami indexes (n) of ~1 (or lower in some cases) should be obtained. Examples are provided where these conditions have been met and first order kinetics (n = 1) were measured as opposed to higher orders (n = 3?4) for the same polymer in the bulk. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1179–1194 相似文献
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Koltsov Iwona Prześniak-Welenc Marta Wojnarowicz Jacek Rogowska Anna Mizeracki Jan Malysa Maria Kimmel Giora 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2273-2284
Journal of Thermal Analysis and Calorimetry - Industrially relevant nanopowder was synthesised by microwave hydrothermal synthesis to obtain well-controlled composition (ZrO2–AlO(OH) system)... 相似文献
97.
C60 derivatives bearing either terminal alkyne or azide functional groups have been prepared and used as building blocks under the copper-mediated Huisgen 1,3-dipolar cycloaddition conditions leading to 1,2,3-triazole derivatives. 相似文献
98.
A series of tetrachloride platinum(IV) compounds of the general formulae PtCl4L2, where L = 1,2,4-triazolo[1,5-a]pyrimidine (tp) (1), 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (dmtp) (2), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp) (3) and 5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one (HmtpO) (4) have been prepared and characterized by thermal analysis, 1H, 13C, 15N, 195Pt NMR and IR spectroscopy. Spectral data suggest that the triazolopyrimidines act as a monodentate ligand via the nitrogen atom N(3). The preliminary assessments of antitumor properties of the four complexes were evaluated as in vitro antiproliferative activity against three cell lines: HL-60 human acute promyelocytic leukemia, SW707 rectal adenocarcinoma and HCV29T bladder cancer. PtCl4(dbtp)2 exhibits high cytotoxic activity against all human cell lines, whereas the other complexes are only moderately active. 相似文献
99.
Listorti A Accorsi G Rio Y Armaroli N Moudam O Gégout A Delavaux-Nicot B Holler M Nierengarten JF 《Inorganic chemistry》2008,47(14):6254-6261
Heteroleptic copper(I) complexes CuPOP-F and CuFc-F have been prepared from a fullerene-substituted phenanthroline ligand and bis[2-(diphenylphosphino)phenyl] ether (POP) and 1,1'-bis(diphenylphosphino)ferrocene (dppFc), respectively. Electrochemical studies indicate that some ground-state electronic interaction between the fullerene subunit and the metal-complexed moiety are present in both CuPOP-F and CuFc-F. Their photophysical properties have been investigated by steady state and time-resolved UV-vis-NIR luminescence spectroscopy and nanosecond laser flash photolysis in a CH2Cl2 solution and compared to those of the corresponding model copper(I) complexes CuPOP and CuFc and of the fullerene model compound F. Selective excitation of the methanofullerene moiety in CuPOP-F results in regular deactivation of the lowest singlet and triplet states, indicating no intercomponent interactions. Conversely, excitation of the copper(I)-complexed unit (405 nm, 40% selectivity) shows that the strongly luminescent triplet metal-to-ligand charge-transfer ((3)MLCT) excited state located at 2.40 eV is quenched by the carbon sphere with a rate constant of 1.6 x 10(8) s(-1). Details on the mechanism of photodynamic processes in CuPOP-F via transient absorption are hampered by the rather unfavorable partition of light excitation between the two chromophores. By determination of the yield of formation of the lowest fullerene triplet level through sensitized singlet oxygen luminescence in the NIR region, it is shown that the final sink of photoinduced processes is always the fullerene triplet. This can be populated via a two-step charge-separation charge-recombination process and a less favored (3)MLCT --> (3)C60 triplet-triplet energy-transfer pathway. In CuFc-F, both of the photoexcited copper(I)-complexed and fullerene moieties are quenched by the presence of the ferrocene unit, most likely via ultrafast energy transfer. 相似文献
100.
Bald I Dabkowska I Illenberger E Ingólfsson O 《Physical chemistry chemical physics : PCCP》2007,9(23):2983-2990
Low energy electron attachment (DEA) to hexafluoroacetone azine (HFAA) leads to a remarkable energy selective excision of CN(-) within a pronounced resonance located at 1.35 eV. The underlying dissociative electron attachment (DEA) reaction involves multiple bond cleavages and rearrangement within the neutral products. A series of further fragment ions (F(-), CF(3)(-), (CF(3))(2)C(-) and (CF(3))(2)CN(-)) are observed from resonant features above 2 eV and only (CF(3))(2)CN(-) is additionally formed within a narrow resonance below 1 eV. In contrast to CN(-) all the remaining fragment ions can be formed by simple bond cleavages with (CF(3))(2)CN(-) being the result of a symmetric decomposition of the target molecule by cleavage of the (N-N) bond with the excess charge localised on either of the identical fragments. Our ab initio calculations predict an adiabatic electron affinity of HFAA close to 2 eV with the geometry of the relaxed anion considerably distorted with respect to that of the neutral molecule. 相似文献