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111.
Seiichiro Imamura Yo-ichi Taniguchi Yoshio Ikeda Saburo Hosokawa Hiroyoshi Kanai Hisanori Ando 《Reaction Kinetics and Catalysis Letters》2002,76(2):201-206
Three kinds of Ru/CeO2 catalysts were prepared. The mobility of the oxygen on Ru and their catalytic activity in the wet oxidation of acetic acid was investigated. Ru was present in the form of RuO2, and TPR experiment showed that the reaction, RuO2 + 2H2 Ru + 2H2O, took place in different temperature ranges depending upon the kind of the catalysts. The catalyst with easily reducible oxygen on Ru had high activity in wet oxidation, and the importance of the release of oxygen from Ru to the reactant was suggested. 相似文献
112.
Taizen Den Dr. Pavel M. Usov Dr. Jaejun Kim Dr. Daisuke Hashizume Dr. Hiroyoshi Ohtsu Prof. Dr. Masaki Kawano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(49):11512-11520
Formation of coordination networks is a complex process affected by a multitude of factors. Many synthetic strategies have been developed that attempt to control these factors and direct the structure of the final product. Coordination bond formation and structural assembly processes, however, typically take place either in the solution or solid states. In comparison, gas-phase network synthesis remains largely unexplored. Herein, two new two-dimensional coordination networks are obtained from the solid–gas phase reaction between ZnX2 (X=I, Br) and the redox-active 2,5,8-tri(4-pyridyl)1,3-diazaphenalene (HTPDAP) ligand. Their structures were solved by ab initio powder X-ray diffraction analysis and feature a novel Zn halide trimeric cluster. This strategy is contrasted with a conventional solvothermal synthesis, which led to a one-dimensional coordination polymer instead. The intrinsic electroactive properties of these materials were probed by solid-state cyclic voltammetry measurements, which revealed the presence of HTPDAP and halide-based processes. Chemical oxidation of the two-dimensional networks by using NOPF6 agent, unexpectedly, led to the formation of a nitrated analog of HTPDAP, the PF6− salt of diprotonated 4,6,7,9-tetranitro-2,5,8-tris(4-pyridyl)diazaphenalene cation (denoted N-TPDAP), which was isolated and characterized. These results provide deeper insights into the oxidation process of HTPDAP-containing networks and uncover unique redox-induced chemical transformations. 相似文献
113.
Keisuke Nakanishi Dr. Hiroyoshi Ohtsu Prof. Dr. Gaku Fukuhara Prof. Dr. Masaki Kawano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(66):15182-15188
An anionic π molecule can form an aggregate when a multi-interactivity is introduced, in sharp contrast to common anionic molecules that are generally difficult to stack on each other. We found that a multi-interactive ligand, 2,5,8-tri(4′-pyridyl)-1,3,4,6,7,9-hexaazaphenalenate (TPHAP−) exhibited a large Stokes shift and an intramolecular charge transfer, both of which were sensitive to hydrogen-bonding media. An anionic potassium salt of TPHAP− in methanol formed various aggregation states depending on the concentration examined; this was revealed by steady-state spectroscopic and fluorescence lifetime measurements. Self-assembling cadmium ions and the ligands can create several morphological crystals that are controlled by the ligand concentration, among which three new structures were determined by single-crystal analysis. The X-ray structures obtained suggest that the aggregation states of the ligand in solution can be transferred to the solid system of the porous coordination networks. 相似文献
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We consider homogenization for weakly coupled systems of Hamilton–Jacobi equations with fast switching rates. The fast switching rate terms force the solutions to converge to the same limit, which is a solution of the effective equation. We discover the appearance of the initial layers, which appear naturally when we consider the systems with different initial data and analyze them rigorously. In particular, we obtain matched asymptotic solutions of the systems and the rate of convergence. We also investigate properties of the effective Hamiltonian of weakly coupled systems and show some examples which do not appear in the context of single equations. 相似文献
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Hiroyoshi Kamogawa Suguru Amemiya 《Journal of polymer science. Part A, Polymer chemistry》1985,23(9):2413-2423
Copolymers of vinyl viologens such as N-vinylbenzyl-N′-yalkyl and N-(γ-methyacryloyloxy)propyl-N′-propyl-4,4′-bipyridinium dihalides and polar aprotic comonomers such as N-vinyl-2-pyrrolidone (VP) and N,N-dimethylacrylamide (DMA) were prepared by the copolymerizations of vinyl viologens with DMA and the chemical modifications of VP copolymers containing reactive halogens. Copolymers containing various viologen anions such as Br?, BF, SO, and I? were also prepared by the anion exchange of copolymers containing Cl?. The photocolor developments of these aprotic copolymers in the film state were completely reversible and faster than for the corresponding copolymers with protic comonomers such as acrylamide and 2-hydroxyethyl acrylate, all with characteristic absorption spectra attributable to single radical cations. 相似文献