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171.
King‐Fu Lin Jing‐Yau Shyu 《Journal of polymer science. Part A, Polymer chemistry》2001,39(18):3085-3092
The early cure behavior of 4,4‐dicyanato 1,1‐diphenolethane resin with and without incorporating Cr(acac)3, Co(acac)3, and Cu(acac)2, respectively, as catalysts was investigated by gel permeation chromatography. The curing intermediates were separated by the column elution method and characterized by Fourier transform infrared, 1H, and 3C NMR spectroscopies. The results indicated that the formed dimer in the early cure stage is a straight chain containing a primary amino group. The formed triazine ring in the trimer has a strong catalytic effect on the remaining cyanate groups so that the reactivity of the trimers was significantly increased. The reactivities of the curing intermediates decreased with molecular size until 7‐mer was reached. The initial monomer consumption is described by second‐order‐rate kinetics. In the presence of metal acetylacetonates, the curing reactions may be accelerated, but they did not change the reaction path and preceding sequence of reactivities. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3085–3092, 2001 相似文献
172.
Ling‐Hai Xie Xian‐Yu Deng Lin Chen Shu‐Fen Chen Ran‐Ran Liu Xiao‐Ya Hou King‐Young Wong Qi‐Dan Ling Wei Huang 《Journal of polymer science. Part A, Polymer chemistry》2009,47(20):5221-5229
The combination of π‐stacked with π‐conjugated building blocks offers an essential strategy to construct multifunctional organic semiconductors (MOSs) with the unique optoelectrical properties. Covalent hybrids can efficiently avoid the intrinsic phase‐separation defects in corresponding blend system. In this contribution, poly(vinylcarbazole) tethered with terfluorene, PVK‐TF, as a double‐channeled π‐stacked and π‐conjugated hybrid (SCH), has been constructed via Friedal‐Crafts click postmodification (FCCP). The chemical structure and optoelectrical property were determined by GPC, UV–vis, PL, TGA, DSC, and CV. Its PL spectra in the annealing thin film at N2 atmosphere without low‐energy emission bands centered at the 530 nm indicates that no π‐stacks between carbazole and TF or among TFs dominate the whole condensed phase, which is in agreement with the intrachain T‐shaped π‐pitched motifs in molecular modeling simulation due to steric hindrance effect in complicated diarylfluorenes (CDAFs). A supporting prototype stable deep‐blue PLED was successfully obtained with an Internationale de l'Eclairage (CIE) coordinates of (0.20, 0.10) and a width at half maximum (FWHM) of about 60 nm at high current density of 100 mA/cm2 (35 V). Deep‐blue PVK‐TF is a promising MOS for hole‐transporting and host materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5221–5229, 2009 相似文献
173.
174.
T. Caspersson Gösta Widström C. C. Lucas E. J. King J. H. W. Lugg H. Barnes R. A. Peters H. Fujiwara E. Kataoka M. X. Sullivan W. C. Hess H. D. Baernstein N. Bulgakow O. Fürth A. Friedrich R. School F. Fromm L. Binet G. Weller Regine Kapeller-Adler Emil Fischer G. Kollmann Mary A. B. Brazier Morner E. Abderhalden O. Kestner Osborne H. D. Dakin E. Schultze K. Spiro P. A. Levene R. H. Aders O. Gerngross W. Deseke W. F. Koelker D. D. van Slyke A. Hynd M. G. Mc Farlane E. Montignie 《Analytical and bioanalytical chemistry》1935,100(1-2):50-60
175.
176.
Values for 〈ΔEdown〉, the average downward energy transferred from the reactant to the bath gas upon collision, have been obtained for highly vibrationally excited undeuterated and per-deuterated isopropyl bromide with the bath gases Ne, Xe, C2H4, and C2D4, at ca. 870 K. The technique of pressure-dependent very low-pressure pyrolysis (VLPP) was used to obtain the data. For C3H7Br, the 〈ΔEdown〉 values (cm?1) are 490 (Ne), 540 (Xe), 820 (C2H4), and 740 (C2D4), and for C3D7Br, 440 (Ne), 570 (Xe), 730 (C2H4), and 810 (C2D4). The uncertainties in these values are ca. ±10%. The 〈ΔEdown〉 values for the inert bath gases Ne and Xe show excellent agreement with the theoretical predictions of the semi-empirical biased random walk model for monatomic/substrate collisional energy exchange [J. Chem. Phys., 80 , 5501 (1984)]. The relative effects of deuteration of the reactant molecule on 〈ΔEdown〉 also compare favorably with the predictions of this theoretical model. Extrapolated high-pressure rate coefficients (s?1) for the thermal decomposition of reactant are 1013.6±0.3 exp(?200 ± 8 kJ mol?1/RT) for C3H7Br and 1013.9±0.3 exp(?207 ± 8 kJ mol±1/RT) for C3D7Br, which are consistent with previous studies and the expected isotope effect. 相似文献
177.
Ho Yin Lo Jörg Bentzien Chuk C. Man Steven S. Pullen Josephine King John P. Wolak Gregory P. Roth 《Tetrahedron letters》2008,49(51):7337-7340
Based on information from molecular modeling, a series of 2-aminobenzimidazoles with pyrrole moieties were designed and synthesized as ITK antagonists. Results showed that a significant improvement of intrinsic and cell-based potency was achieved. X-ray crystallographic analysis of an inhibitor complex with ITK confirmed the prediction from the de novo design that the pyrrole moiety of the inhibitor would form an additional hydrogen bonding interaction with Glu436 in the catalytic domain, and hence improve overall binding affinity of the inhibitor. 相似文献
178.
179.
S. Sabetay und J. King 《Fresenius' Journal of Analytical Chemistry》1933,92(7-8):305
Ohne Zusammenfassung 相似文献
180.
The Chern-Simons gauge theory is studied using a functional integral quantization. This leads to a differential equation for expectations of Wilson lines. The solution of this differential equation is shown to be simply related to the two-variable Jones polynomial of the corresponding link, in the case where the gauge group isSU(N). A similar equation has been used before to get the Jones polynomial from a braid representation of the link. The main novelty of our approach is that we get the Jones polynomial from a plat representation of the link. 相似文献