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991.
The Uncommon Channel‐Based Ln‐MOFs for Highly Selective Fe3+ Detection and Superior Rhodamine B Adsorption 下载免费PDF全文
Dr. Shanghua Xing Dr. Qiming Bing Lifei Song Prof. Guanghua Li Prof. Jingyao Liu Zhan Shi Shouhua Feng Ruren Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(45):16230-16235
Two new isostructural 3D lanthanide–organic frameworks [H2N(Me)2] [Ln3(OH)(bpt)3(H2O)3] (DMF)2?(H2O)4 ( 1‐Ln ; Ln=Sm and Eu) with a 1D channel (25 Å) have been successfully assembled from the rare trinuclear [Ln3(OH)(COO)9] clusters and biphenyl‐3,4′,5‐tricarboxylic acid (H3bpt) and exhibit high stability towards water in the pH range 3–10. MOF 1‐Eu is a promising luminescent probe for sensing Fe3+ in aqueous solution and is also selective towards rhodamine B (RhB) with a superior adsorption capacity of 735 mg g?1, which is the highest among the reported Ln‐MOFs for RhB removal so far. Periodic DFT calculations further confirmed the selective adsorption of rhodamine B over other dyes. 相似文献
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Transition Metal Chemistry - Lignin is the second most abundant component in biomass, considered as the most abundant and available renewable source of aromatics in Nature. The depolymerization of... 相似文献
995.
Recent discoveries of the novel properties of arsenides prompt us to theoretically predict the tetragonal AsTiZr ternary compound under pressure, in order to exploit new functional materials. The structure, elastic and thermodynamic properties of AsTiZr have been investigated under various pressures, based on density functional theory (DFT). For the sake of consistency, the approach of the generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof (PBE) was used. The calculated structural data at zero pressure are in good agreement with previous report. The dependence of relative changes of lattice parameters (a0 and c0) and volume V0, elastic constants, bulk, shear and Young's modulus, and Debye temperature on pressure has been investigated. The thermodynamic properties like heat capacity C, enthalpy E, free energy F and entropy S with pressure are successfully obtained and discussed. 相似文献
996.
Yile Chen Zhongshen Zhan Jianhai Wang Yanfei Shen Songqin Liu Yuanjian Zhang 《中国化学快报》2018,29(3):437-440
Thanks to the dissolution of bulk carbon nitride (CN), a heterojunction of CN and sulfur-doped CN was constructed via a solution-based processing way, which led to a more homogeneous composite and an improved photocatalytic H2 production activity up to 230% with respect to that by conventional impregnating. 相似文献
997.
We prove birational boundedness results on complete intersections with trivial canonical class of base point free divisors in (some version of) Fano varieties. Our results imply in particular that Batyrev–Borisov toric construction produces only a bounded set of Hodge numbers in any given dimension, even as the codimension is allowed to grow. 相似文献
998.
Tao Qian Juanjuan Wang Tiantian Cheng Xiaoli Zhan Qinghua Zhang Fengqiu Chen 《Journal of polymer science. Part A, Polymer chemistry》2016,54(13):2040-2049
The poly(methyl methacrylate)‐b‐poly(2‐[[[[2‐(perfluorohexyl)]‐sulfonyl]‐amino]ehthyl] methacrylate) (PMMA‐b‐PC6SMA) copolymers were successfully synthesized for the first time using activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) method. Under optimized reaction conditions, the degree of polymerization (DP) of resulting copolymers increased approximately linearly with monomer conversion. Structures of a well‐defined block copolymer were determined by GPC, FT–IR, and 1H‐NMR spectra. Results from AFM and contact angle measurements of polymer films revealed the presence of block segments derived from PC6SMA, as indicated by the obvious increase in hydrophobicity and oleophobicity. The relationship between surface composition and surface wetting ability was confirmed by XPS and AFM spectra. Compared with the random copolymer PMMA‐co‐PC6SMA, C6SMA dosages in the PMMA‐b‐PC6SMA copolymers were greatly decreased, which retained its hydrophobic and oleophobic properties. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2040–2049 相似文献
999.
Léon Witteman Tim Evers Zhan Shu Dr. Martin Lutz Prof. Dr. Robertus J. M. Klein Gebbink Dr. Marc‐Etienne Moret 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):6087-6099
A range of silanes was synthesized by the reaction of HSiCl3 with iminopyrrole derivatives in the presence of NEt3. In certain cases, intramolecular hydrosilylation converts the imine ligand into an amino substituent. This reaction is inhibited by factors such as electron‐donating substitution on Si and steric bulk. The monosubstituted (DippIMP)SiHMeCl (DippIMP=2‐[N‐(2,6‐diisopropylphenyl)iminomethyl]pyrrolide), is stable towards hydrosilylation, but slow hydrosilylation is observed for (DippIMP)SiHCl2. Reaction of two equivalents of DippIMPH with HSiCl3 results in the hydrosilylation product (DippAMP)(DippIMP)SiCl (DippAMP=2‐[N‐(2,6‐diisopropylphenyl)aminomethylene]pyrrolide), but the trisubsitituted (DippIMP)3SiH is stable. Monitoring the hydrosilylation reaction of (DippIMP)SiHCl2 reveals a reactive pathway involving ligand redistribution reactions to form the disubstituted (DippAMP)(DippIMP)SiCl as an intermediate. The reaction is strongly accelerated in the presence of chloride anions. 相似文献
1000.
Haijun Fan Zhiguo Zhang Yongfang Li Xiaowei Zhan 《Journal of polymer science. Part A, Polymer chemistry》2011,49(6):1462-1470
Two copolymers of fluorene and thiophene with conjugated side‐chain pending acceptor end group of cyanoacetate ( P2 ) and malononitrile ( P3 ) were synthesized. Both polymers exhibit good thermal stability and low highest occupied molecular orbital level (?5.5 eV). In comparison with P2 , P3 exhibits stronger UV–vis absorption and higher hole mobility. Polymer solar cells based on P3 :PC71BM exhibits a power conversion efficiency of 1.33% under AM 1.5, 100 mW/cm2, which is three times of that based on P2 :PC71BM. The higher efficiency is attributed to better absorption, higher hole mobility, and the reduced phase separation scale in P3 :PC71BM blend. The aggregate domain size in P3 :PC71BM blend is 50 nm, much smaller than that in P2 :PC71BM blend (200 nm). Tiny difference in the end groups on side chains of P2 and P3 leads to great difference in phase separation scale, charge transport, and efficiency of their photovoltaic devices. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献