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891.
Liang Weng Jiao‐Jiao Yan He‐Lou Xie Guan‐Qun Zhong Si‐Qi Zhu Hai‐Liang Zhang Er‐Qiang Chen 《Journal of polymer science. Part A, Polymer chemistry》2013,51(9):1912-1923
A series of novel polymerized ionic liquids (PILs) contained imidazolium, poly (2,5‐bis{[6‐(1‐butyl‐3′‐imidazolium)hexyl] oxy carbonyl}styrene salts) (denoted as P1? X?, X??Br?, BF4?, PF6? and TFSI?) were successfully synthesized via radical polymerization. The chemical structures of the monomers and their corresponding PILs were confirmed by 1H NMR, 13C NMR, and Fourier transform infrared spectroscopy. Thermogravimetric analysis results showed that these PILs had excellent thermal stability. The phase transitions and liquid‐crystalline (LC) behaviors of these polymers were investigated by differential scanning calorimetry, polarized light microscopy (PLM), and wide‐angle X‐ray diffraction. The combined experimental results showed that all the PILs could form hexagonal columnar (?H) LC ordered structures because of the strong interaction between the anions and cations in the side groups except for P1? TFSI?. The conductivities of monomers and PILs were sketchily investigated, and monomers had higher conductivities than those of conprespoding PILs. For comparison, we have synthesized a polymer without counter‐anion, but similar to the chemical structure of P1? X?, poly (2, 5‐bis{[6‐(4‐butoxy‐4′‐oxy phenyl) hexyl] oxycarbonyl} styrene) (denoted as P2). In this case, phenyl took place of imidazolium of side chain, and LC ordered structure did not form. The comparison between P1? X? and P2 suggested that ion played an important role in the constructing of LC ordered structure. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
892.
893.
Qian Liang Haifeng Yue Weishan Zhou Qiang Wei Prof. Dr. Qiang Ru Yuan Huang Hongtao Lou Prof. Dr. Fuming Chen Prof. Dr. Xianhua Hou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(57):14225-14233
A large number of lithium batteries have been retiring from the market of energy storage. Thus, recycling of the used electrode materials is becoming urgent. In this study, an industrial machinery processing was used to recover the crystal structure of the waste LiCoO2 materials with the combination of small-scale equipment repair technology. The results show that the crystal parameters of the repaired LiCoO2 material become small, the unit cell volume is reduced, and the crystal structure tends to be stable. The Co−O bond length of 1.9134 nm, O−Co−O bond angle of 94.72°, the (003) interplanar spacing of 0.467 nm indicate the excellent recovery level of the repaired LiCoO2. In addition, the electrochemical performance of the repaired LiCoO2 material is greatly improved, compared with the waste material. The capacity of the repaired electrode material can be maintained at 120 mAh g−1 after 100 cycles at the current density of 0.2C. The promising rate performance of the repaired electrode material demonstrates the stable structure. This research work provides a large-scale method for the direct recovery of LiCoO2 with the reduction of unnecessary energy and reagent consumption, which will be beneficial to the environmental protection. 相似文献
894.
Yongheng Shi Prof. Dr. Guilong Zhao Yuanyuan Lou Yuli Wang Hua Shao Wei Liu Weiren Xu Lida Tang 《中国化学》2011,29(6):1192-1198
Three novel gem‐dimethyl C‐glucosides were designed as sodium‐glucose co‐transporter 2 (SGLT2) inhibitors, and their syntheses started from D‐glucose and three 2‐substituted‐5‐bromobenzoic acids were achieved via a facile 8‐step protocol, with the key step being anhydrous aluminum chloride‐catalyzed Friedel‐Crafts alkylation of tertiary alcohols and phenetol. These three SGLT2 inhibitors were evaluated in vivo with a mice oral glucose tolerance test (OGTT), and the anti‐hyperglycemic activities of all these three compounds were comparable with that of the positive control Dapagliflozin. 相似文献
895.
896.
Variable coefficient nonlinear systems, the Korteweg
de Vries (KdV), the modified KdV (mKdV) and the nonlinear
Schr?dinger (NLS) type equations, are derived from the nonlinear
inviscid barotropic nondivergent vorticity equation in a beta-plane
by means of the multi-scale expansion method in two different ways,
with and without the so-called y-average trick. The
non-auto-B\"acklund transformations are found to transform the
derived variable coefficient equations to the corresponding standard
KdV, mKdV and NLS equations. Thus, many possible exact solutions can
be obtained by taking advantage of the known solutions of these
standard equations. Further, many approximate solutions of the
original model are ready to be yielded which might be applied to
explain some real atmospheric phenomena, such as atmospheric
blocking episodes. 相似文献
897.
This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt=Au,uxuxx+Bu,ux,ut which admits the derivative-dependent functional separable solutions DDFSSs). We also extend the concept of the DDFSS to cover other variable separation approaches. 相似文献
898.
在吡啶溶液中细菌叶绿素a分子S3-S1转换过程的实时观测 总被引:1,自引:0,他引:1
899.
非理想二元表面活性剂复配增效理论的进一步研究 总被引:4,自引:0,他引:4
在Rubingh与Rosen提出非理想二元表面活性剂复配增效条件基础上,利用相分离模型和正规溶液理论,导出了体系降低表面张力的能力增效条件βs-βm〈0,及最佳摩尔分数α1,最低表面张力γcmc12和γcmc处对应的临界胶束浓度cmc12。通过作三条γ-logc曲线或两条γ-logc曲线加上一个cmc值的方法,对C12NMe3Br-C12SO4Na,C12NMe3Br-C8SO4N两种复配体系进行验证,计算结果与实验结果相符。 相似文献
900.