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61.
The statistical properties of dynamic elongated speckle patterns produced in the far-field diffraction region by a moving diffuse object under illumination of the dichromatic laser beam are experimentally investigated by means of a correlation method. The experimental results show that the correlation length of the normalized autocorrelation function of time-varying dichromatic speckle intensity fluctuations depends strongly on the fibrous radial structure of elongated speckle patterns. The qualitative discussions are given for the experimental results. 相似文献
62.
Hiroshi Takai 《Journal of Functional Analysis》1981,43(2):202-208
Let Aθ be the irrational rotation algebra. Then there exist non approximately bounded pregenerators δi(i = 1, 2) of Aθ with the same domain such that given a 1-derivation δ of Aθ with D(δ) = D(δi), there exist (k,l)∈2 and an approximately bounded 1-derivation δ3of Aθ such that δ = kδ1 + lδ2 + δ3, which can be considered as a solution of a problem of Sakai for two dimensional space quantizations. 相似文献
63.
64.
The reduction mechanism of speckles appearing in laser-microscope images is studied theoretically and experimentally when an object is illuminated by laser light through a rotating multimode optical fiber. The principle of the speckle reduction is based on independent addition of microscope images with boiling-like speckles as a result of the rotational motion of the optical fiber used for illumination. Especially, the speckle reduction is evaluated from first-order statistics of the speckle intensity in which its saturation effect is taken into consideration. 相似文献
65.
Tachikawa T Takai Y Tojo S Fujitsuka M Irie H Hashimoto K Majima T 《The journal of physical chemistry. B》2006,110(26):13158-13165
The photocatalytic degradation processes of ethylene glycol (EG) during the UV or visible light irradiation of pure anatase and nitrogen (N)-doped TiO2 powders (TiO(2-x)N(x), x = 0, 0.002, 0.003, and 0.007) were investigated using time-resolved diffuse reflectance (TDR) and solid-state NMR spectroscopies. The TDR spectra and time traces observed for the charge carriers indicated that the scavenging of photogenerated holes (h+) by EG occurred during the 355-nm laser photolysis of the N-doped TiO2 powders, while no direct oxidation reaction of EG by h+ occurred during the 460-nm laser photolysis, although the charge carriers were sufficiently generated upon excitation. The solid-state magic-angle spinning (MAS) NMR measurements revealed that EG is preferentially chemisorbed on the surface of the N-doped TiO2 powders, in contrast to the pure TiO2, and degrades under visible light irradiation. 相似文献
66.
The magnetism of nanographite (stacked nanographene sheets)-based nanoporous carbon is investigated in relation to the interaction with acid guest species. The concentration of the localized spins of non-bonding π-electron state (edge state) localized in the nanographene edges decreases upon the sulfonation of nanographene edges through charge-transfer interaction with sulfonic groups. The sulfonation of nanographene edges enhances the hydrophilic nature of the edges, resulting in the easiness in the water adsorption into the nanopores. This enhances the mechanical compression effect of water molecules condensed in the nanopores on the nanographite domains, resulting in the decrease in the spin concentration. The change in the magnetism upon water uptake reveals ferrimagnetic nature of individual nanographene sheets. The adsorption of HCl having no oxidation ability shows a mechanical effect on the edge-state spins similar to water adsorption. The spin concentration is reduced in two-step manner by the charge-transfer interaction with guest concentrated HNO3 that is strong oxidant. In the presence of H2O molecules in diluted HNO3 the cooperation of mechanical and charge-transfer interactions creates also a two-step change in the magnetism. 相似文献
67.
The variation with temperature of the charge on the surface of NaCl single crystals has been measured directly by means of vibrating capacitor probe. The charge is negative at room temperature, in agreement with theory based on values of the free energy of vacancy formation, decreases with increase of temperature in two stages to a zero value at the isoelectric temperature, and then becomes positive. Values of isoelectric temperature obtained on surfaces are consistent with those obtained by experiments on charged dislocations, which suggests that surfaces could be used to obtain accurate values of the free energy of formation of cation and anion vacancies. 相似文献
68.
Takaaki Takatsuka Hideki Tomita Tetsu Sonoda Volker Sonnenschein Chika Sakamoto Hiroki Mita Takuma Noto Chikara Ito Shigetaka Maeda Tetsuo Iguchi Michiharu Wada Klaus Wendt Iain Moore 《Hyperfine Interactions》2013,216(1-3):41-46
93Nb(n, n′)93mNb reaction allows retrospective estimation of integrated fast neutron dose in nuclear reactor. We proposed isomer-selective trace analysis of 93mNb by Resonance Ionization Mass Spectrometry (RIMS) combined with a gas-jet atomic source and an injection locked Ti:Sapphire laser system operated at several kHz. Resonant ionization spectroscopy of Nb in gas-jet using Ti:Sapphire laser was demonstrated. 相似文献
69.
70.
Iridium‐Catalyzed Sequential Silylation and Borylation of Heteroarenes Based on Regioselective C−H Bond Activation 下载免费PDF全文
Dr. Masahito Murai Naoki Nishinaka Prof. Dr. Kazuhiko Takai 《Angewandte Chemie (International ed. in English)》2018,57(20):5843-5847
An iridium‐catalyzed regioselective sequential silylation and borylation of heteroarenes was developed, which represents a rare example of unsymmetrical intermolecular C?H bond difunctionalization through the introduction of two different functionalities during a one‐pot transformation. Although the substrate scope for the dehydrogenative silylation of heteroarenes has been limited mainly to electron‐rich five‐membered rings, the current reaction proceeds with both electron‐rich and electron‐deficient heteroarenes with the aid of heteroatom‐directing C?H bond activation. The regioselectivity of the second borylation was controlled by both steric factors and the electronic effect of the silyl group installed in the first step. In combination with the classic cross‐coupling reaction, this method provides rapid access to multisubstituted heteroarenes. 相似文献