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71.
The title compound was obtained from 1,3-dichloro-adamantane and some silylating reagents with Na-HMPA. 相似文献
72.
Dieter Wohrle Jörg Gitzel Gerhard Krawczyk Eishun Tsuchida Hiroyoki Ohno Ichiro Okura 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10-11):1227-1254
Metal complexes of covalently bound porphyrins are used as sensitive probes for several investigations. Substituted derivatives of tetraphenyl-porphin, phthalocyanine, and naphthalocyanine are synthesized at positively and negatively charged as well as uncharged polymers. The photo-redox activities were studied under irradiation with visible light in the presence of a donor and an acceptor. The triplet life times of covalently bound porphyrin moieties are strongly enhanced compared with the analogous monomeric porphyrins. In addition, the polymer binding results in higher photocatalytic activity. The electron-transfer reactions of Mn(III)-containing porphyrins using the reducing agent dithionite are strongly influenced by the polymer environment. In contrast to monomeric Mn(III)-porphyrins, the porphyrins containing polymers exhibit a two-step reduction which may be due to the change of the conformation of the polymer coil. The catalytic epoxidation of 2,5-dihydrofuran with hypochlorite with formation of 3,4-epoxytetrahydrofuran occurs with water-soluble porphyrins in water. No influence of the polymer environment exists. The different reactions require reaction times from milliseconds up to hours. 相似文献
73.
Yuki Yanagisawa Takeshi Kageyama Naohisa Wada Masatoshi Tanaka Shin‐ya Ohno 《Photochemistry and photobiology》2013,89(6):1490-1496
The time‐dependent characteristics of firefly bioluminescence initiated by manual injection of adenosine triphosphate (ATP) into buffer solution containing luciferin (Ln), luciferase (Luc) and Mg2+ were measured with a resolution of 10 ms, and compared with those obtained by photolysis of caged ATP. The time course depends on pH; both rise and decay rates decrease when pH is lowered from 7.8 to 6.8. In contrast, the parameter λ in the kinetic formula related to diffusion of ATP is almost independent of pH. The pH dependence of the time course of bioluminescence can be explained by the same pH tendency as the rate of ATP binding at the active site of Luc. The time‐resolved spectra can be decomposed into two Gaussian components with maxima at 2.2 and 2.0 eV. At pH 7.8, the band at 2.2 eV is more intense than that at 2.0 eV for all three concentration conditions. At lower pH, the band at 2.2 eV becomes weaker than that at 2.0 eV. The intensity ratio of the 2.0 and 2.2 eV bands is constant for duration time of 600 s for both injection and photolysis experiments, and the above conclusions are unaffected by the concentration ratio [Ln]/[Luc]. 相似文献
74.
75.
Investigating sorption-driven dissolved organic matter fractionation by multidimensional fluorescence spectroscopy and PARAFAC 总被引:1,自引:0,他引:1
Banaitis MR Waldrip-Dail H Diehl MS Holmes BC Hunt JF Lynch RP Ohno T 《Journal of colloid and interface science》2006,304(1):271-276
Soil organic matter is involved in many ecosystem processes, such as nutrient supply, metal solubilization, and carbon sequestration. This study examined the ability of multidimensional fluorescence spectroscopy and parallel factor analysis (PARAFAC) to provide detailed chemical information on the preferential sorption of higher-molecular-weight components of natural organic matter onto mineral surfaces. Dissolved organic matter (DOM) from soil organic horizons and tree leaf tissues was obtained using water extracts. The suite of fluorescence spectra was modeled with PARAFAC and it was revealed that the DOM extracts contained five fluorescing components: tryptophan-like (peak location at excitation <255 nm:emission 342 nm), tyrosine-like (276 nm:312 nm), and three humic-substance-like components (<255 nm:456 nm, 309 nm:426 nm, <255 nm:401 nm). In general, adsorption onto goethite and gibbsite increased with increasing DOM molecular weight and humification. PARAFAC analysis of the pre- and post-sorption DOM indicated that the ordering of sorption extent was humic-like components (average 91% sorption) > tryptophan-like components (52% sorption) > tyrosine-like components (29% sorption). This differential sorption of the modeled DOM components in both the soil organic horizon and leaf tissue extracts led to the fractionation of DOM. The results of this study demonstrate that multidimensional fluorescence spectroscopy combined with PARAFAC can quantitatively describe the chemical fractionation process due to the interaction of DOM with mineral surfaces. 相似文献
76.
Takuya Hosokawa Keiji Izuchi Shûichi Ohno 《Integral Equations and Operator Theory》2005,53(4):509-526
We study properties of the topological space of weighted composition operators on the space of bounded analytic functions
on the open unit disk in the uniform operator topology. Moreover, we characterize the compactness of differences of two weighted
composition operators. 相似文献
77.
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80.
A detailed rotational analysis of the microwave spectrum between 26.5 and 40 GHz of phosphaethene, CH2PH, has been carried out. This molecule is the simplest member of a new class of unstable molecules—the phosphaalkenes. The species can be produced by pyrolysis of (CH3)2PH, CH3PH2 and also somewhat more efficiently from Si(CH3)3CH2PH2. Full first-order centrifugal distortion analyses have been carried out for both 12CH231PH and 12CH231PD yielding: A0 = 138 503.20(21), B0 = 16 418.105(26), and C0 = 14 649.084(28) MHz for 12CH231PH. The 101-000μA lines have also been detected for 13CH2PH, cis-CDHPH and trans-CHDPH. These data have enabled an accurate structure determination to be carried out which indicates: . The dipole moment components have been determined as μA = 0.731 (2), μB = 0.470 (3), μ = 0.869 (3) D for CH2PH; μA = 0.710 (2), μB = 0.509 (10), μ = 0.874 (7) D for CH2PD. 相似文献