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111.
Synthesis and antifungal activities of (2R,3R)-2-aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives as topical antifungal agents. 总被引:1,自引:0,他引:1
H Ogura H Kobayashi K Nagai T Nishida T Naito Y Tatsumi M Yokoo T Arika 《Chemical & pharmaceutical bulletin》1999,47(10):1417-1425
2-Aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives I were prepared by ring-opening reaction of epoxides II with excess amine, and their antifungal activities were evaluated as topical agents. Azolyl-cyclic amine derivatives with a methylene group showed extremely strong activity with a broad spectrum in vitro. In general, anti-Trichophyton mentagrophytes activities of most of the topical antifungal agents are substantially reduced by addition of keratin (a major constituent of the keratinized tissue). However, the triazole derivative (2R,3R)-2-(2,4-difluorophenyl)-3-(4-methylenepiperidino)-1-(1H-1,2 ,4- triazol-1-yl)-2-butanol ((-)-40, KP-103) showed very little deactivation by addition of keratin. This biological characteristic of triazole derivative (-)-40 resulted in excellent therapeutic efficacy on dermatophytosis superior to that of the corresponding imidazole derivative ((-)-41). 相似文献
112.
113.
It has been clarified that words in written texts are classified into two groups called Type-I and Type-II words. The Type-I words are words that exhibit long-range dynamic correlations in written texts while the Type-II words do not show any type of dynamic correlations. Although the stochastic process of yielding Type-II words has been clarified to be a superposition of Poisson point processes with various intensities, there is no definitive model for Type-I words. In this study, we introduce a Hawkes process, which is known as a kind of self-exciting point process, as a candidate for the stochastic process that governs yielding Type-I words; i.e., the purpose of this study is to establish that the Hawkes process is useful to model occurrence patterns of Type-I words in real written texts. The relation between the Hawkes process and an existing model for Type-I words, in which hierarchical structures of written texts are considered to play a central role in yielding dynamic correlations, will also be discussed. 相似文献
114.
T. G. Kim X. -L. Wang R. Kaji M. Ogura 《Physica E: Low-dimensional Systems and Nanostructures》2000,7(3-4)
Lasing from the ground state electron and heavy-hole-like transition of quantum wire (QWR) is demonstrated for the first time at room temperature, with an oxide-isolated V-grooved GaAs/AlGaAs triple QWR laser grown by flow-rate modulation epitaxy (FME). The lasing peaks at all temperatures (4–300 K) are in reasonably good agreement with both the photon energies of the peaks of the photoluminescence curves and the numerical calculation of the electronic sub-band energy states of the corresponding QWR structure. These results are considered to be responsible for the reduced heterointerface inhomogeneities (the Stokes shift 0.3 meV) of the FME grown QWR, giving a low-loss wave guide in the QWR laser. 相似文献
115.
The active state of palladium for NO reduction with methane (CH4-SCR) was investigated by comparing the catalytic activity of Pd/H-ZSM-5 with that of PdO/SiO2. High catalytic activity for CH4-SCR was given by Pd/H-ZSM-5 in the temperature range of 300–500 °C. PdO/SiO2 catalyzed the reaction between NO2 and CH4 in the absence of oxygen, which retarded the reaction by consuming CH4 in combustion. CH4 combustion occurred on either zeolite-supported or silica-supported catalyst, while NO preferentially retarded the combustion
on Pd/H-ZSM-5. NO was found to be chemisorbed on the palladium sites in zeolite, while it was hardly chemisorbed on PdO/SiO2. NaCl titration showed that the palladium species in zeolite are Pd2+ cations content, on which NO is strongly chemisorbed resulting in high selectivity for CH4-SCR. 相似文献
116.
Cho J Sarangi R Kang HY Lee JY Kubo M Ogura T Solomon EI Nam W 《Journal of the American Chemical Society》2010,132(47):16977-16986
Metal-dioxygen adducts are key intermediates detected in the catalytic cycles of dioxygen activation by metalloenzymes and biomimetic compounds. In this study, mononuclear cobalt(III)-peroxo complexes bearing tetraazamacrocyclic ligands, [Co(12-TMC)(O(2))](+) and [Co(13-TMC)(O(2))](+), were synthesized by reacting [Co(12-TMC)(CH(3)CN)](2+) and [Co(13-TMC)(CH(3)CN)](2+), respectively, with H(2)O(2) in the presence of triethylamine. The mononuclear cobalt(III)-peroxo intermediates were isolated and characterized by various spectroscopic techniques and X-ray crystallography, and the structural and spectroscopic characterization demonstrated unambiguously that the peroxo ligand is bound in a side-on η(2) fashion. The O-O bond stretching frequency of [Co(12-TMC)(O(2))](+) and [Co(13-TMC)(O(2))](+) was determined to be 902 cm(-1) by resonance Raman spectroscopy. The structural properties of the CoO(2) core in both complexes are nearly identical; the O-O bond distances of [Co(12-TMC)(O(2))](+) and [Co(13-TMC)(O(2))](+) were 1.4389(17) ? and 1.438(6) ?, respectively. The cobalt(III)-peroxo complexes showed reactivities in the oxidation of aldehydes and O(2)-transfer reactions. In the aldehyde oxidation reactions, the nucleophilic reactivity of the cobalt-peroxo complexes was significantly dependent on the ring size of the macrocyclic ligands, with the reactivity of [Co(13-TMC)(O(2))](+) > [Co(12-TMC)(O(2))](+). In the O(2)-transfer reactions, the cobalt(III)-peroxo complexes transferred the bound peroxo group to a manganese(II) complex, affording the corresponding cobalt(II) and manganese(III)-peroxo complexes. The reactivity of the cobalt-peroxo complexes in O(2)-transfer was also significantly dependent on the ring size of tetraazamacrocycles, and the reactivity order in the O(2)-transfer reactions was the same as that observed in the aldehyde oxidation reactions. 相似文献
117.
118.
Shoumei Li Yukio Ogura Frank N. Proske 《Journal of Mathematical Analysis and Applications》2003,285(1):250-263
We give central limit theorems for generalized set-valued random variables whose level sets are compact both in or in a Banach space under milder conditions than those obtained recently by the latter two authors. 相似文献
119.
Irakli Javakhishvili Masaru Tanaka Keiko Ogura Katja Jankova Sren Hvilsted 《Macromolecular rapid communications》2012,33(4):319-325
Graft copolymers composed of poly(2‐methoxyethyl acrylate) are prepared employing controlled radical polymerization techniques. Linear backbones bearing atom transfer radical polymerization (ATRP) initiating sites are obtained by reversible addition–fragmentation chain transfer copolymerization of 2‐methoxyethyl acrylate (MEA) and 2‐(bromoisobutyryloxy)ethyl methacrylate (BriBuEMA) as well as 2‐hydroxyethyl methacrylate and BriBuEMA in a controlled manner . MEA is then grafted from the linear macroinitiators by Cu (I)‐mediated ATRP. Fairly high molecular weights (>120 000 Da) and low polydispersity indices (1.17–1.38) are attained. Thermal investigations of the graft copolymers indicate the presence of the freezing bound water, and imply that the materials may exhibit blood compatibility. 相似文献
120.
Kotaro Ogura Jun Yano Kotaro Kisaka Hideo Goto 《Journal of polymer science. Part A, Polymer chemistry》1994,32(1):33-38
Polypyrrole (PPy) was deposited electrochemically on a platinum plate from a nitric acid solution of pyrrole. The PVC/PPy composite film was finally obtained by casting poly(vinyl chloride) (PVC) onto the PPy electrode from a tetrahydrofuran solution of PVC. The prepared composite film was irradiated at 90°C with a low-pressure mercury lamp in the stream of hydrogen gas saturated with steam, and the PVC film was dehydrochlorinated, leading to the formation of conjugated polyene. The electrical conductivity (σ) of the PVC film in the irradiated composite film was reveled: σ=2.51 × 10?5S cm?1. By iodine doping, σ was further enhanced up to 5.04 X 10?3 S cm?1. The tensile strength of the irradiated composite film became larger than that of the original PVC film; i.e., the stress at break was: 461 (composite film); 401 kg cm?2 (PVC). These results were brought about by the doping of radical species to the conjugated polyene. The anion, NO?3, doped during the electrodeposition of PPy was photodecomposed to generate radical NO2 and this species was doped to the polyene, resulting in the formation of electrically conductive PVC and mechanically improved composite film. © 1994 John Wiley & Sons, Inc. 相似文献