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971.
Vacancy‐Induced Electronic Structure Variation of Acceptors and Correlation with Proton Conduction in Perovskite Oxides 下载免费PDF全文
Hye‐Sung Kim Ahreum Jang Dr. Si‐Young Choi Prof. WooChul Jung Prof. Sung‐Yoon Chung 《Angewandte Chemie (International ed. in English)》2016,55(43):13499-13503
In most proton‐conducing perovskite oxides, the electrostatic attraction between negatively charged acceptor dopants and protonic defects having a positive charge is known to be a major cause of retardation of proton conduction, a phenomenon that is generally referred to as proton trapping. We experimentally show that proton trapping can be suppressed by clustering of positively charged oxygen vacancies to acceptors in BaZrO3?δ and BaCeO3?δ. In particular, to ensure the vacancy–acceptor association is effective against proton trapping, the valence electron density of acceptors should not significantly vary when the oxygen vacancies cluster, based on the weak hybridization between the valence d or p orbitals of acceptors and the 2p orbitals of oxygen. 相似文献
972.
Inside Back Cover: Vacancy‐Induced Electronic Structure Variation of Acceptors and Correlation with Proton Conduction in Perovskite Oxides (Angew. Chem. Int. Ed. 43/2016) 下载免费PDF全文
973.
974.
V.?B.?BalakirevaEmail author A.?Yu.?Stroeva V.?P.?Gorelov 《Russian Journal of Electrochemistry》2005,41(5):535-539
Values of partial conductions (ionic: protonic, oxygen, hole) and their activation energies in LaYO3 are determined at 700–1050°C, pO2 ranging from air to 10−15 Pa, and pH2O = 0.04–13.5 kPa for different versions of doping with calcium (when introduced into the lanthanum or yttrium sublattices, or into both sublattices simultaneously). The conductivity increases in the series La0.97Ca0.03YO3 − α < LaY0.97Ca0.03O3 − α < La0.985Y0.985Ca0.03O3 − α, which means that the stoichiometric composition with a 1 : 1 ratio between Y and La has the highest conductivity.__________Translated from Elektrokhimiya, Vol. 41, No. 5, 2005, pp. 610–615.Original Russian Text Copyright © 2005 by Balakireva, Stroeva, Gorelov. 相似文献
975.
Pb1-xZnxS (x = 0 to 0.4 in steps of 0.1) ternary semiconductor material shave been prepared by co-precipitation method. The structural and electrical studies have been carried out to understand the influence of Zinc on activation energy. X-ray diffractograms showed that the Pb1-xZnxS compounds are polycrystalline in nature with cubic phase. The temperature-dependent conductivity measured in the range 300–4 K showed a change in the conduction mechanism at 62 K and 31 K. The activation energies evaluated at low and very low temperature regions. Activation energy increases and conductivity decreases with the increase of Zn in Pb1-xZnxS compounds. The samples are exhibiting low freezing temperature points indicating their capability to use in low temperature applications. 相似文献
976.
Aggregation of Giant Cerium–Bismuth Tungstate Clusters into a 3D Porous Framework with High Proton Conductivity 下载免费PDF全文
Jian‐Cai Liu Qing Han Dr. Li‐Juan Chen Prof. Dr. Jun‐Wei Zhao Prof. Dr. Carsten Streb Prof. Dr. Yu‐Fei Song 《Angewandte Chemie (International ed. in English)》2018,57(28):8416-8420
The exploration of high nuclearity molecular metal oxide clusters and their reactivity is a challenge for chemistry and materials science. Herein, we report an unprecedented giant molecular cerium–bismuth tungstate superstructure formed by self‐assembly from simple metal oxide precursors in aqueous solution. The compound, {[W14CeIV6O61]([W3Bi6CeIII3(H2O)3O14][B‐α‐BiW9O33]3)2}34? was identified by single‐crystal X‐ray diffraction and features 104 metal centers, a relative molar mass of ca. 24 000 and is ca. 3.0×2.0×1.7 nm3 in size. The cluster anion is assembled around a central {Ce6} octahedron which is stabilized by several molecular metal oxide shells. Six trilacunary Keggin anions ([B‐α‐BiW9O33]9?) cap the superstructure and limit its growth. In the crystal lattice, water‐filled channels with diameters of ca. 0.5 nm are observed, and electrochemical impedance spectroscopy shows pronounced proton conductivity even at low temperature. 相似文献
977.
978.
Data on previous conductimetric studies of ionic transport in fluoride composites and vitreous materials are compiled. The F- conductivity of composites 21SrF2 · 79LaF3 (content, mol %) and 34NaF · 66PbF2 reaches 0.007 S cm-1 at 500 K and that of glasses based on InF3 and PbF2, 6 × 10-5 S cm-1 at 400 K, which exceeds that of -PbF2 and LaF3 crystals. 相似文献
979.
Nobuhito Imanaka Tomohiro Ueda Gin-ya Adachi 《Journal of Solid State Electrochemistry》2003,7(4):239-243
The ionic conduction of mono-, di-, and trivalent ions in solids is popular in solid state science and the next target ion
species to migrate in solids are tetravalent ions. Here, a tetravalent cation conductor which shows high conductivity, comparable
to the conductivity range of the representative divalent oxide anion conductors, was artificially designed by strictly selecting
the constituent elements and the structure. The tetravalent ion conducting solid electrolyte proposed here shows considerable
high ion conductivity and promising applications, such as in rechargeable batteries and chemical sensors for global environmental
monitoring, are greatly expected.
Electronic Publication 相似文献
980.
Composting technologies rely on standard methods for quality determination. The maturity of a compost is assayed by self-heating experiments in Dewar-vessels. The resulting maximum temperature is classified on a five-level scale. This study demonstrated systematic errors that might occur when assays are performed in Dewars of different size. The vessels were characterized as heat conduction calorimeters and the processes of biochemical decomposition and heat generation and autothermic effects (temperature) were evaluated quantitatively.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献