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Ming Liu Sandrine Peyrat Nicolas Illy Véronique Wintgens Blandine Brissault Jacques Penelle Valessa Barbier 《Journal of polymer science. Part A, Polymer chemistry》2014,52(16):2337-2345
We report the synthesis and ion‐binding properties of four poly(crown‐ethers) displaying either one or two crown‐ethers (15‐crown‐5 or 18‐crown‐6) on every third carbon alongside the backbone. The polymers were synthesized by living anionic ring‐opening polymerization of disubstituted cyclopropane‐1,1‐dicarboxylates monomers. Cation binding of the polychelating polymers and corresponding monomers to Na+ and K+ was evaluated by picrate extraction and isothermal calorimetry titration. This novel family of poly(crown‐ethers) demonstrated excellent initial binding of the alkali ions to the polymers, with a higher selectivity for potassium. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2337–2345 相似文献
994.
Convenient Access to Fluorescent Probes by Chemoselective Acylation of Hydrazinopeptides: Application to the Synthesis of the First Far‐Red Ligand for Apelin Receptor Imaging 下载免费PDF全文
Dr. Jean‐François Margathe Dr. Xavier Iturrioz Pierre Regenass Iuliia A. Karpenko Dr. Nicolas Humbert Dr. Hugues de Rocquigny Prof. Marcel Hibert Dr. Catherine Llorens‐Cortes Dr. Dominique Bonnet 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1399-1405
Herein, we develop a convenient method to facilitate the solution‐phase fluorescent labelling of peptides based on the chemoselective acylation of α‐hydrazinopeptides. This approach combines the advantages of using commercially available amine‐reactive dyes and very mild conditions, which are fully compatible with the chemical sensitivity of the dyes. The usefulness of this approach was demonstrated by the labelling of apelin‐13 peptide. Various fluorescent probes were readily synthesized, enabling the rapid optimization of their affinities for the apelin receptor. Thus, the first far‐red fluorescent ligand with sub‐nanomolar affinity for the apelin receptor was characterized and shown to track the receptor efficiently in living cells by fluorescence confocal microscopy. 相似文献
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A benzophenone‐naphthalimide derivative as versatile photoinitiator of polymerization under near UV and visible lights 下载免费PDF全文
Jing Zhang Nicolas Zivic Frédéric Dumur Pu Xiao Bernadette Graff Didier Gigmes Jean Pierre Fouassier Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2015,53(3):445-451
A benzophenone‐naphthalimide derivative (BPND) bearing tertiary amine groups has been developed as a high‐performance photoinitiator in combination with 2,4,6‐tris(trichloromethyl)‐1,3,5‐triazine or an iodonium salt for both the free radical polymerization (FRP) of acrylates and the cationic polymerization (CP) of epoxides upon exposure to near UV and visible LEDs (385–470 nm). BPND can even produce radicals without any added hydrogen donor. The photochemical mechanisms are studied by molecular orbital calculations, steady state photolysis, electron spin resonance spin trapping, fluorescence, cyclic voltammetry and laser flash photolysis techniques. These novel BPND based photoinitiating systems exhibit an efficiency higher than that of the well‐known camphorquinone‐based systems (FRP and CP) or comparable to that of bis(2,4,6‐trimethylbenzoyl)‐phenylphosphineoxide (FRP at λ ≤ 455 nm). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 445–451 相似文献
997.
We provide an effective characterization of the planar octagonal tilings which admit weak local rules. As a corollary, we show that they are all based on quadratic irrationalities, as conjectured by Thang Le in the 1990s. 相似文献
998.
Dorian Sonet Mattéo Cayla Dr. Raphaël Méreau Estelle Morvan Aline Lacoudre Dr. Nicolas Vanthuyne Muriel Albalat Dr. Dario M. Bassani Dr. Antoine Scalabre Dr. Emilie Pouget Prof. Dr. Brigitte Bibal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(72):e202202695
Chiral trifluoromethyl alcohol groups were introduced at the hindered ortho positions of 9,10-diphenylanthracenes to investigate their effects on the physical properties and reactivity towards oxidative dearomatization. In such compact structures, the position in different quadrants and the preferred orientation of the −CH(OH)CF3 groups were determined by the relative and absolute configurations of each stereoisomer, respectively. As a consequence, the stereochemistry governs the organization of the H-bonded molecules in single crystals (homochiral dimers vs ribbon), whereas in chlorinated solvents, they all behave as discrete compounds. Concerning their reactivity, the stereospecific dearomative oxidation of these molecules leads to 9,10-bis-spiro-isobenzofuran-anthracenes, when using organic single-electron transfer oxidants. The chiroptical properties of the alcohols and the corresponding dearomatized products were compared and showed an important modulation of the intensity. 相似文献
999.