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101.
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103.
Xiong Guohong Wang Zhiyu Qian Guodong Fan Xianping Wang Minquan 《Journal of Sol-Gel Science and Technology》2000,18(1):21-27
Using a newly developed in-situ syntheses technique during sol-gel process, copper phthalocyanine (CuPc) is synthesized in-situ in silica xerogel matrix homogeneously. It has been confirmed by UV-Vis and IR spectroscopies that the copper ions which existed in the form of complex-ions [Cu(H2O)4]2+ and [CuCl4]2– in the stages of sol and wet gel were destroyed in the heat treatment process, meanwhile the copper phthalocyanine molecules were synthesized in-situ gradually during the wet gel to xerogel transition. The dimerization phenomenon of CuPc in the composite is suppressed greatly because the in-situ synthesized CuPc molecules were well isolated in the micro-pores of the xerogel matrix. The doping concentration of Copper phthalocyanine in sol-gel derived matrix can be enhanced also by this in-situ synthesis method. 相似文献
104.
Masakatsu Kasuya Tatsuo Taniguchi Ryuhei Motokawa Michinari Kohri Keiki Kishikawa Takayuki Nakahira 《Journal of polymer science. Part A, Polymer chemistry》2013,51(19):4042-4051
We developed a novel fluorescence labeling technique for quantification of surface densities of atom transfer radical polymerization (ATRP) initiators on polymer particles. The cationic P(St‐CPEM‐C4DMAEMA) and anionic P(St‐CPEM) polymer latex particles carrying ATRP‐initiating chlorine groups were prepared by emulsifier‐free emulsion polymerization of styrene (St), 2‐(2‐chloropropionyloxy)ethyl methacrylate (CPEM), and N‐n‐butyl‐N,N‐dimethyl‐N‐(2‐methacryloyloxy)ethylammonium bromide (C4DMAEMA). ATRP initiators on the surface of polymer particles were converted into azide groups by sodium azide, followed by fluorescent labeling with 5‐(N,N‐dimethylamino)‐N′‐(prop‐2‐yn‐1‐yl)naphthalene‐1‐sulfonamide (Dansyl‐alkyne) by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC). The reaction time required for both azidation of ATRP‐initiating groups and successive fluorescence labeling of azide groups with Dansyl‐alkyne by CuAAC were investigated in detail by FTIR and fluorescence spectral measurement, respectively. The ATRP initiator densities on the cationic P(St‐CPEM‐C4DMAEMA) and anionic P(St‐CPEM) particle surfaces were estimated to be 0.21 and 0.15 molecules nm?2, respectively, which gave close agreement with values previously determined by a conductometric titration method. The fluorescence labeling through click chemistry proposed herein is a versatile technique to quantify the surface ATRP initiator density both on anionic and cationic polymer particles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4042–4051 相似文献
105.
Zheng Chen Daniel R. Dreyer Zong‐quan Wu Kelly M. Wiggins Zhenhua Jiang Christopher W. Bielawski 《Journal of polymer science. Part A, Polymer chemistry》2011,49(6):1421-1426
The synthesis and characterization of a novel family of main‐chain carbazole‐containing polymers using copper‐catalyzed azide‐alkyne cycloaddition chemistry is reported. The reactions were performed under mild conditions using readily available copper catalysts and ligands, which afforded polymeric products with Mws up to 18 kDa. Using a range of techniques, the polymers were found to exhibit a glass transition temperature (Tg) of 85 °C, high thermal stability (Td = 274 °C), and high photoluminescent quantum efficiency (?f = 0.29; λem = 448 nm), which underscore their potential for use in organic light‐emitting diodes or other emissive devices, particularly where efficient blue emission is of value. The approach described offers practical advantages over other synthetic methods used to prepare main‐chain carbazole‐containing polymers, especially with regard to the lack of need for rigorously inert conditions and the absence of byproducts generated during the polymerization reaction. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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107.
Eda Gungor Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2008,46(20):6703-6711
The terminal alkyne homocoupling reaction (oxidative alkyne coupling) is presented here as a new route for the preparation of A2B2 type 4‐miktoarm star copolymer. The block copolymer with terminal alkyne at the junction point prepared by NMP‐ATRP and ROP‐NMP sequential routes is coupled via diyne formation to give (PS)2‐(PMMA)2 and (PCL)2‐(PS)2 4‐miktoarm star polymers, respectively, by using a combination of (PPh3)2PdCl2/PPh3/CuI in a solvent mixture of Et3N/CH3CN at room temperature for 72 h. The molecular weight, intrinsic viscosity ([η]), radius of gyration (Rg), and hydrodynamic radius (Rh) of A2B2 4‐miktoarm star copolymers were calculated using triple‐detection GPC as results of three detectors response. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6703–6711, 2008 相似文献
108.
Nobukazu Taniguchi 《Tetrahedron》2009,65(14):2782-1357
A copper-catalyzed synthesis of β-haloalkenyl sulfides or selenides was carried out by addition of dichalcogenides and tetrabutylammonium halides to internal alkynes. The present reaction anti- and regio-selectively afforded the corresponding alkenyl chalocogenides, and took advantage of both organochalcogenide-groups on dichalcogenide. Furthermore, the reaction under oxygen atmosphere could employ thiols. The use of the procedure could easily synthesize (Z)-tamoxifen from diphenyl acetylene in three steps. 相似文献
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110.
Treatment of alkynes with ortho-formyl and acetyl phenylboronic acids in the presence of a cobalt catalyst resulted in the formation of 2,3-disubstituted indenols in good yields. When aryl silyl alkynes were used, 2-aryl-3-silyl indenols were obtained regioselectively in good yields. 相似文献