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951.
A Mild Dihydrobenzooxaphosphole Oxazoline/Iridium Catalytic System for Asymmetric Hydrogenation of Unfunctionalized Dialins
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Dr. Bo Qu Dr. Lalith P. Samankumara Dr. Shengli Ma Dr. Keith R. Fandrick Dr. Jean‐Nicolas Desrosiers Dr. Sonia Rodriguez Dr. Zhibin Li Dr. Nizar Haddad Dr. Zhengxu S. Han Keith McKellop Scott Pennino Dr. Nelu Grinberg Dr. Nina C. Gonnella Dr. Jinhua J. Song Dr. Chris H. Senanayake 《Angewandte Chemie (International ed. in English)》2014,53(52):14428-14432
Air‐stable P‐chiral dihydrobenzooxaphosphole oxazoline ligands were designed and synthesized. When they were used in the iridium‐catalyzed asymmetric hydrogenation of unfunctionalized 1‐aryl‐3,4‐dihydronaphthalenes under one atmosphere pressure of H2, up to 99:1 e.r. was obtained. High enantioselectivities were also observed in the reduction of the exocyclic imine derivatives of 1‐tetralones. 相似文献
952.
In this study, we developed a novel magnetic nanocomposite superabsorbent (MNS) for effective removal of mercury ions from aqueous solutions. The preparation method of MNS is easy, fast, simple, effective, and safe. The MNSs were synthesized via the simultaneous formation of magnetic iron oxide nanoparticles (MIONs) and in situ radical solution polymerization of superabsorbents based on poly(acryl amide) grafted onto starch backbones in the presence of graphene oxide (GO) nanosheets. The chemical structure, morphology and phase composition of the obtained MSNs were characterized using FTIR, SEM, TEM, XRD, and VSM techniques. The effects of parameters and also the morphology of MNSs on the adsorption of Hg2+ were investigated in detail through batch experiments. Furthermore, the adsorption kinetics fits well with the pseudosecond- order model. The equilibrium data also fitted the Langmuir sorption isotherms well. Moreover, the thermodynamic parameters shown that the sorption process was feasible, spontaneous and endothermic. 相似文献
953.
Frontispiece: Ordered Layered Dendrimers Constructed from Two Known Dendrimer Families: Inheritance and Emergence of Properties
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954.
Corrigendum: Induction of a Proton Gradient across a Gold‐Supported Biomimetic Membrane by Electroenzymatic H2 Oxidation
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955.
Janwa El‐Maiss Thierry Darmanin Elisabeth Taffin de Givenchy Sonia Amigoni Julian Eastoe Masanobu Sagisaka Frédéric Guittard 《Journal of Polymer Science.Polymer Physics》2014,52(11):782-788
This work concerns new superhydrophobic surfaces, generated by replacing long fluorocarbon chains, which bioaccumulate, with short chains whilst at the same time retaining oleophobic properties. Here, is described the synthesis of novel 3,4‐propylenedioxythiophene derivatives containing both a short fluorocarbon chain (perfluorobutyl) and a hydrocarbon chain of various lengths (ethyl, butyl and hexyl). Superhydrophobic (θwater > 150°) surfaces with good oleophobic properties (60° > θhexadecane > 80°) have been obtained by electrodeposition using cyclic voltammetry. Surprisingly, the lowest hystereses and sliding angles (Lotus effect) are obtained with the shortest alkyl chains due to the presence of microstructures made of nanofibers on the surfaces, whereas, the longest alkyl chains leads to nanosheets with high adhesion (Petal effect). Such materials are potential candidates for biomedical applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 782–788 相似文献
956.
Utilization of poly(vinylchloride) and poly(vinylidenefluoride) as macroinitiators for ATRP polymerization of hydroxyethyl methacrylate: Electroanalytical and graft‐copolymerization studies
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Sonia Lanzalaco Alessandro Galia Flavia Lazzano Rosalia Rita Mauro Onofrio Scialdone 《Journal of polymer science. Part A, Polymer chemistry》2015,53(21):2524-2536
The utilization of poly(vinylchloride) (PVC) and poly(vinylidenefluoride) (PVDF) as macroinitiators for atom transfer radical polymerization (ATRP) of hydroxyethyl methacrylate (HEMA) was studied performing electroanalytical investigations and “grafting from” experiments to evaluate the potential modification of such commercial polymers by ATRP. The study was performed changing various operating parameters such as the nature of the copper salt, the ligand, the solvent, the temperature, and the reaction time. Electroanalytical data suggest that PVC can be easily activated by both CuCl/Tris(2‐pyridylmethyl)amine (TPMA) and CuCl/Tris[2‐(dimethylamino)ethyl]amine (Me6TREN), two catalytic systems widely adopted for ATRP reactions, in a wide range of operating conditions. PVDF is more difficult to be activated, due to the higher strength of the C? F bond. In particular, the utilization of high temperature and of a more reductant redox couple such as Cu(I)Me6TREN/Cu(II)Me6TREN was needed to achieve a significant degree of grafting. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2524–2536 相似文献
957.
958.
Highly Fluorinated Tris(indazolyl)borate Silylamido Complexes of the Heavier Alkaline Earth Metals: Synthesis,Characterization, and Efficient Catalytic Intramolecular Hydroamination
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Nuria Romero Sorin‐Claudiu Roşca Dr. Yann Sarazin Prof. Jean‐François Carpentier Dr. Laure Vendier Sonia Mallet‐Ladeira Dr. Chiara Dinoi Prof. Michel Etienne 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):4115-4125
Heteroleptic silylamido complexes of the heavier alkaline earth elements calcium and strontium containing the highly fluorinated 3‐phenyl hydrotris(indazolyl)borate {F12‐Tp4Bo, 3Ph}? ligand have been synthesized by using salt metathesis reactions. The homoleptic precursors [Ae{N(SiMe3)2}2] (Ae=Ca, Sr) were treated with [Tl(F12‐Tp4Bo, 3Ph)] in pentane to form the corresponding heteroleptic complexes [(F12‐Tp4Bo, 3Ph)Ae{N(SiMe3)2}] (Ae=Ca ( 1 ); Sr ( 3 )). Compounds 1 and 3 are inert towards intermolecular redistribution. The molecular structures of 1 and 3 have been determined by using X‐ray diffraction. Compound 3 exhibits a Sr ??? MeSi agostic distortion. The synthesis of the homoleptic THF‐free compound [Ca{N(SiMe2H)2}2] ( 4 ) by transamination reaction between [Ca{N(SiMe3)2}2] and HN(SiMe2H)2 is also reported. This precursor constitutes a convenient starting material for the subsequent preparation of the THF‐free complex [(F12‐Tp4Bo, 3Ph)Ca{N(SiMe2H)2}] ( 5 ). Compound 5 is stabilized in the solid state by a Ca???β‐Si?H agostic interaction. Complexes 1 and 3 have been used as precatalysts for the intramolecular hydroamination of 2,2‐dimethylpent‐4‐en‐1‐amine. Compound 1 is highly active, converting completely 200 equivalents of aminoalkene in 16 min with 0.50 mol % catalyst loading at 25 °C. 相似文献
959.
Marc Devillard Dr. Emmanuel Nicolas Dr. Andreas W. Ehlers Jana Backs Sonia Mallet‐Ladeira Dr. Ghenwa Bouhadir Dr. J. Chris Slootweg Prof.Dr. Werner Uhl Dr. Didier Bourissou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):74-79
Hitherto unknown Au→Al interactions have been evidenced upon coordination of the geminal phosphorus–aluminum Lewis pair Mes2PC(?CHPh)AltBu2 (Mes=2,4,6‐trimethylphenyl). Four different gold(I) complexes featuring alkyl (Me), aryl (Ph, C6F5), and alkynyl (C?CPh) co‐ligands have been prepared. X‐ray diffraction analyses show that P→Au→Al bridging coordination induces noticeable bending of the ligand (the PCAl bond angle shrinks by 13°). This new type of transition metal→Lewis acid interaction has been analyzed by DFT calculations. 相似文献
960.
Jorge Leganés Bayón Prof. Ana Sánchez-Migallón Prof. Ángel Díaz-Ortiz Dr. Carlos Alberto Castillo Dr. Inma Ballesteros-Yáñez Prof. Sonia Merino Prof. Ester Vázquez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17069-17080
Electromagnetically driven drug delivery systems stand out among stimulus-responsive materials due to their ability to release cargo on demand by remote stimulation, such as light, near infrared (NIR) or microwave (MW) radiation. MW-responsive soft materials, such as hydrogels, generally operate at 2.45 GHz frequencies, which usually involves rapid overheating of the scaffold and may affect tissue surrounding the target location. In contrast, 915 MHz MW penetrate deeper tissues and are less prone to induce rapid overheating. In order to circumvent these limitations, we present here for the first time a graphene-based hydrogel that is responsive to MW irradiation of ν=915 MHz. This system is a candidate soft scaffold to deliver a model hydrophobic drug. The graphene present in the hydrogel acts as a heat-sink and avoids overheating of the scaffold upon MW irradiation. In addition, the microwave trigger stimulates the in vitro delivery of the model drug, thus suggesting a remote and deep-penetrating means to deliver a drug from a delivery reservoir. Moreover, the MW-triggered release of drug was observed to be enhanced under acidic conditions, where the swelling state is maximum due to the swelling-induced pH-responsiveness of the hydrogel. The hybrid composite described here is a harmless means to deliver remotely a hydrophobic drug on demand with a MW source of 915 MHz. Potential use in biomedical applications were evaluated by cytotoxicity tests. 相似文献