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991.
An Aluminophosphate Molecular Sieve with 36 Crystallographically Distinct Tetrahedral Sites
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Jun Kyu Lee Alessandro Turrina Liangkui Zhu Seungwan Seo Dr. Daliang Zhang Dr. Paul A. Cox Prof. Paul A. Wright Prof. Shilun Qiu Prof. Suk Bong Hong 《Angewandte Chemie (International ed. in English)》2014,53(29):7480-7483
The structure of the new medium‐pore aluminophosphate molecular sieve PST‐6 is determined by the combined use of rotation electron diffraction tomography, synchrotron X‐ray powder diffraction, and computer modeling. PST‐6 was prepared by calcination of another new aluminophosphate material with an unknown structure synthesized using diethylamine as a structure‐directing agent, which is thought to contain bridging hydroxy groups. PST‐6 has 36 crystallographically distinct tetrahedral sites in the asymmetric unit and is thus crystallographically the most complex zeolitic structure ever solved. 相似文献
992.
Perturbation of Spin Crossover Behavior by Covalent Post‐Synthetic Modification of a Porous Metal–Organic Framework
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John E. Clements Dr. Jason R. Price Dr. Suzanne M. Neville Prof. Cameron J. Kepert 《Angewandte Chemie (International ed. in English)》2014,53(38):10164-10168
Covalent post‐synthetic modification is a versatile method for gaining high‐level synthetic control over functionality within porous metal–organic frameworks and for generating new materials not accessible through one‐step framework syntheses. Here we apply this topotactic synthetic approach to a porous spin crossover framework and show through detailed comparison of the structures and properties of the as‐synthesised and covalently modified phases that the modification reaction proceeds quantitatively by a thermally activated single‐crystal‐to‐single‐crystal transformation to yield a material with lowered spin‐switching temperature, decreased lattice cooperativity, and altered color. Structure–function relationships to emerge from this comparison show that the approach provides a new route for tuning spin crossover through control over both outer‐sphere and steric interactions. 相似文献
993.
Synthesis of Two‐Dimensional Transition‐Metal Phosphates with Highly Ordered Mesoporous Structures for Lithium‐Ion Battery Applications
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Dan Yang Dr. Ziyang Lu Dr. Xianhong Rui Xiao Huang Dr. Hai Li Dr. Jixin Zhu Wenyu Zhang Prof. Yeng Ming Lam Prof. Huey Hoon Hng Prof. Hua Zhang Prof. Qingyu Yan 《Angewandte Chemie (International ed. in English)》2014,53(35):9352-9355
Materials with ordered mesoporous structures have shown great potential in a wide range of applications. In particular, the combination of mesoporosity, low dimensionality, and well‐defined morphology in nanostructures may exhibit even more attractive features. However, the synthesis of such structures is still challenging in polar solvents. Herein, we report the preparation of ultrathin two‐dimensional (2D) nanoflakes of transition‐metal phosphates, including FePO4, Mn3(PO4)2, and Co3(PO4)2, with highly ordered mesoporous structures in a nonpolar solvent. The as‐obtained nanoflakes with thicknesses of about 3.7 nm are constructed from a single layer of parallel‐packed pore channels. These uniquely ordered mesoporous 2D nanostructures may originate from the 2D assembly of cylindrical micelles formed by the amphiphilic precursors in the nonpolar solvent. The 2D mesoporous FePO4 nanoflakes were used as the cathode for a lithium‐ion battery, which exhibits excellent stability and high rate capabilities. 相似文献
994.
A Molecular Approach to Self‐Supported Cobalt‐Substituted ZnO Materials as Remarkably Stable Electrocatalysts for Water Oxidation
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Johannes Pfrommer Dr. Michael Lublow Anahita Azarpira Dr. Caren Göbel Marcel Lücke Dr. Alexander Steigert Martin Pogrzeba Dr. Prashanth W. Menezes Dr. Anna Fischer Dr. Thomas Schedel‐Niedrig Prof. Dr. Matthias Driess 《Angewandte Chemie (International ed. in English)》2014,53(20):5183-5187
In regard to earth‐abundant cobalt water oxidation catalysts, very recent findings show the reorganization of the materials to amorphous active phases under catalytic conditions. To further understand this concept, a unique cobalt‐substituted crystalline zinc oxide (Co:ZnO) precatalyst has been synthesized by low‐temperature solvolysis of molecular heterobimetallic Co4?xZnxO4 (x=1–3) precursors in benzylamine. Its electrophoretic deposition onto fluorinated tin oxide electrodes leads after oxidative conditioning to an amorphous self‐supported water‐oxidation electrocatalyst, which was observed by HR‐TEM on FIB lamellas of the EPD layers. The Co‐rich hydroxide‐oxidic electrocatalyst performs at very low overpotentials (512 mV at pH 7; 330 mV at pH 12), while chronoamperometry shows a stable catalytic current over several hours. 相似文献
995.
Dr. Ran Mo Tianyue Jiang Prof. Dr. Zhen Gu 《Angewandte Chemie (International ed. in English)》2014,53(23):5815-5820
A liposome‐based co‐delivery system composed of a fusogenic liposome encapsulating ATP‐responsive elements with chemotherapeutics and a liposome containing ATP was developed for ATP‐mediated drug release triggered by liposomal fusion. The fusogenic liposome had a protein–DNA complex core containing an ATP‐responsive DNA scaffold with doxorubicin (DOX) and could release DOX through a conformational change from the duplex to the aptamer/ATP complex in the presence of ATP. A cell‐penetrating peptide‐modified fusogenic liposomal membrane was coated on the core, which had an acid‐triggered fusogenic potential with the ATP‐loaded liposomes or endosomes/lysosomes. Directly delivering extrinsic liposomal ATP promoted the drug release from the fusogenic liposome in the acidic intracellular compartments upon a pH‐sensitive membrane fusion and anticancer efficacy was enhanced both in vitro and in vivo. 相似文献
996.
Inside Back Cover: Controlled Electropolymerization of Ruthenium(II) Vinylbipyridyl Complexes in Mesoporous Nanoparticle Films of TiO (Angew. Chem. Int. Ed. 19/2014)
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997.
Facile One‐Pot,One‐Step Synthesis of a Carbon Nanoarchitecture for an Advanced Multifunctonal Electrocatalyst
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Dr. Yang Hou Prof. Junhong Chen 《Angewandte Chemie (International ed. in English)》2014,53(25):6496-6500
A one‐pot/one‐step synthesis strategy was developed for the preparation of a nitrogen‐doped carbon nanoarchitecture with graphene‐nanosheet growth on the inner surface of carbon nanotubes (CNTs). The N‐graphene/CNT hybrids exhibit outstanding electrocatalytic activity for several important electrochemical reactions as a result of their unique morphology and defect structures, such as high but uniform nitrogen doping, graphene insertion into CNTs, considerable surface area, and the presence of iron nanoparticles. The high‐yield synthetic process features high efficiency, low‐cost, straightforward operation, and simple equipment. 相似文献
998.
Dr. Yoshikazu Ito Dr. Yoichi Tanabe Dr. H.‐J. Qiu Dr. Katsuaki Sugawara Dr. Satoshi Heguri Dr. Ngoc Han Tu Dr. Khuong Kim Huynh Dr. Takeshi Fujita Prof. Takashi Takahashi Prof. Katsumi Tanigaki Prof. Mingwei Chen 《Angewandte Chemie (International ed. in English)》2014,53(19):4822-4826
We report three‐dimensional (3D) nanoporous graphene with preserved 2D electronic properties, tunable pore sizes, and high electron mobility for electronic applications. The complex 3D network comprised of interconnected graphene retains a 2D coherent electron system of massless Dirac fermions. The transport properties of the nanoporous graphene show a semiconducting behavior and strong pore‐size dependence, together with unique angular independence. The free‐standing, large‐scale nanoporous graphene with 2D electronic properties and high electron mobility holds great promise for practical applications in 3D electronic devices. 相似文献
999.
Dr. Ryo Tsunashima Yoshifumi Iwamoto Yusuke Baba Chisato Kato Katsuya Ichihashi Dr. Sadafumi Nishihara Prof. Katsuya Inoue Prof. Katsuya Ishiguro Prof. Yu‐Fei Song Prof. Tomoyuki Akutagawa 《Angewandte Chemie (International ed. in English)》2014,53(42):11228-11231
In a mixed‐valence polyoxometalate, electrons are usually delocalized within the cluster anion because of low level of inter‐cluster interaction. Herein, we report the structure and electrical properties of a single crystal in which mixed‐valence polyoxometalates were electrically wired by cationic π‐molecules of tetrathiafulvalene substituted with pyridinium. Electron‐transport characteristics are suggested to represent electron hopping through strong interactions between cluster and cationic π‐molecules. 相似文献
1000.