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181.
Hayes AM Morris DJ Clarkson GJ Wills M 《Journal of the American Chemical Society》2005,127(20):7318-7319
Ruthenium dimer 6 (readily available in two steps from TsDPEN) is converted directly to monomeric asymmetric transfer hydrogenation catalyst 3 in situ under the conditions employed for ketone reduction. Catalyst 3 is a significantly more active catalyst for this application than the untethered derivative, exhibits higher enantioselectivities across a range of substrates, and appears to be highly stable to the reaction conditions. It is active at loadings of as low as 0.01 mol %, and reductions at the 0.1 mol % level are complete within 20 min at 80 degrees C without significant loss of enantioselectivity. 相似文献
182.
Synthesis and characterisation of a [Ni8] single molecule magnet and another octanuclear nickel cage
Bell A Aromí G Teat SJ Wernsdorfer W Winpenny RE 《Chemical communications (Cambridge, England)》2005,(22):2808-2810
Two new octanuclear nickel(II) cage complexes are reported; the second is a new single molecule magnet. 相似文献
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Laye RH Murrie M Ochsenbein S Bell AR Teat SJ Raftery J Güdel HU McInnes EJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(24):6215-6220
Superheating alcohol solutions of simple trimetallic vanadium(III) precursors gives the octa- and decametallic vanadium(III) clusters [V(8)(OEt)(8)(OH)(4)(O(2)CPh)(12)] (1) and [V(10)(OMe)(20)(O(2)CMe)(10)] (2). Cluster 2 is the largest vanadium(III) cluster synthesised to date. Thus solvothermal synthetic techniques are an excellent route to high-nuclearity vanadium(III) clusters. Both 1 and 2 consist of a planar or near-planar array of V(III) ions. The metal ions in 1 are bridged by either a micro(2)-hydroxide and two micro(2)-benzoate groups or two micro(2)-ethoxides and a micro(2)-benzoate groups, the two bridging arrangements alternating around the ring. In 2 each pair of neighbouring metal ions is bridged by two micro(2)-methoxides and a micro(2)-acetate, and this molecule is the V(III) analogue of Lippard's famous "ferric wheel". Preliminary magnetic susceptibility studies show the exchange coupling in both complexes to be antiferromagnetic in nature, with the coupling stronger in 1 than in 2. 相似文献
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One‐Step Microfluidic Fabrication of Polyelectrolyte Microcapsules in Aqueous Conditions for Protein Release 下载免费PDF全文
Dr. Liyuan Zhang Dr. Li‐Heng Cai Dr. Philipp S. Lienemann Dr. Torsten Rossow Dr. Ingmar Polenz Queralt Vallmajo‐Martin Dr. Martin Ehrbar Dr. Hui Na Dr. David J. Mooney Dr. David A. Weitz 《Angewandte Chemie (International ed. in English)》2016,55(43):13470-13474
We report a microfluidic approach for one‐step fabrication of polyelectrolyte microcapsules in aqueous conditions. Using two immiscible aqueous polymer solutions, we generate transient water‐in‐water‐in‐water double emulsion droplets and use them as templates to fabricate polyelectrolyte microcapsules. The capsule shell is formed by the complexation of oppositely charged polyelectrolytes at the immiscible interface. We find that attractive electrostatic interactions can significantly prolong the release of charged molecules. Moreover, we demonstrate the application of these microcapsules in encapsulation and release of proteins without impairing their biological activities. Our platform should benefit a wide range of applications that require encapsulation and sustained release of molecules in aqueous environments. 相似文献
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Elastically Flexible Crystals have Disparate Mechanisms of Molecular Movement Induced by Strain and Heat 下载免费PDF全文
Dr. Aidan J. Brock Jacob J. Whittaker Joshua A. Powell Dr. Michael C. Pfrunder Dr. Arnaud Grosjean Prof. Simon Parsons Prof. John C. McMurtrie Prof. Jack K. Clegg 《Angewandte Chemie (International ed. in English)》2018,57(35):11325-11328
Elastically flexible crystals form an emerging class of materials that exhibit a range of notable properties. The mechanism of thermal expansion in flexible crystals of bis(acetylacetonato)copper(II) is compared with the mechanism of molecular motion induced by bending and it is demonstrated that the two mechanisms are distinct. Upon bending, individual molecules within the crystal structure reversibly rotate, while thermal expansion results predominantly in an increase in intermolecular separations with only minor changes to molecular orientation through rotation. 相似文献