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141.
T. Oishi M. Goto Y. Pihosh A. Kasahara M. Tosa 《Applied Physics A: Materials Science & Processing》2005,81(3):507-510
A microdot pattern of multiple organic molecules was prepared. Fluorescent molecules, which absorb visible light, were added to a commercial ultraviolet photopolymerization polymer solution and the polymer solution was polymerized by irradiating with nanosecond pulsed visible laser light. The size and the shape of the polymerized dots differed with the irradiation condition and the kind of the added molecules. Based on these results, a microdot pattern of multiple organic molecules was prepared by repeating a micropatterning process with the molecules. PACS 82.50.Hp; 81.65.Cf; 81.05.Lg 相似文献
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144.
Hydroxy propyl methyl cellulose acetate succinate high grade (AS-HG) and ethyl cellulose (EC) mixture microcapsules containing cefadroxil or theophylline were prepared by a solvent evaporation method in liquid paraffin dissolved sorbitan tri-stearate as a dispersing agent, and their sustained-release properties were evaluated. The microcapsules prepared with AS-HG:EC (in a 2:5 weight ratio) mixture containing 20% of cefadroxil or theophylline exhibited apparent zero-order releasing pattern in pH 6 to 8, at 50 rpm and 37 degrees C (paddle method). These microcapsules were administered orally to beagle dogs and the plasma concentrations of cefadroxil or theophylline were measured periodically. As a result of in vivo investigation, a satisfactory sustained-release plasma pattern and an apparent zero-order process in the gastrointestinal absorption were confirmed by deconvolution analysis of both drugs. 相似文献
145.
Yamasaki Y Sagayama H Goto T Matsuura M Hirota K Arima T Tokura Y 《Physical review letters》2007,98(14):147204
Magnetic ferroelectrics or multiferroics, which are currently extensively explored, may provide a good arena to realize a novel magnetoelectric function. Here we demonstrate the genuine electric control of the spiral magnetic structure in one such magnetic ferroelectric, TbMnO3. A spin-polarized neutron scattering experiment clearly shows that the spin helicity, clockwise or counterclockwise, is controlled by the direction of spontaneous polarization and hence by the polarity of the small electric field applied on cooling. 相似文献
146.
Monte Carlo simulation of full energy spectrum of electrons emitted from silicon in Auger electron spectroscopy
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N. Cao B. Da Y. Ming S. F. Mao K. Goto Z. J. Ding 《Surface and interface analysis : SIA》2015,47(1):113-119
A Monte Carlo simulation including surface excitation, Auger electron‐ and secondary electron production has been performed to calculate the energy spectrum of electrons emitted from silicon in Auger electron spectroscopy (AES), covering the full energy range from the elastic peak down to the true‐secondary‐electron peak. The work aims to provide a more comprehensive understanding of the experimental AES spectrum by integrating the up‐to‐date knowledge of electron scattering and electronic excitation near the solid surface region. The Monte Carlo simulation model of beam–sample interaction includes the atomic ionization and relaxation for Auger electron production with Casnati's ionization cross section, surface plasmon excitation and bulk plasmon excitation as well as other bulk electronic excitation for inelastic scattering of electrons (including primary electrons, Auger electrons and secondary electrons) through a dielectric functional approach, cascade secondary electron production in electron inelastic scattering events, and electron elastic scattering with use of Mott's cross section. The simulated energy spectrum for Si sample describes very well the experimental AES EN(E) spectrum measured with a cylindrical mirror analyzer for primary energies ranging from 500 eV to 3000 eV. Surface excitation is found to affect strongly the loss peak shape and the intensities of the elastic peak and Auger peak, and weakly the low energy backscattering background, but it has less effect to high energy backscattering background and the Auger electron peak shape. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
147.
Polymerization of optically active disubstituted acetylene monomers by Pd catalyst bearing bulky phosphine ligand
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Yuta Goto Yu Miyagi Natsuhiro Sano Fumio Sanda 《Journal of polymer science. Part A, Polymer chemistry》2017,55(18):3011-3016
Chloro- and aryl-substituted acetylene monomers having an optically active group were polymerized by a Pd catalyst [(tBu3P)PdMeCl] bearing a bulky phosphine ligand, and by MoCl5 for comparison. The corresponding disubstituted acetylene polymers with Mn's = 2000–19,500 and 6900–10,800 were obtained in 29–83% and 11–62% yields when the Pd and Mo catalysts were used, respectively. The formation of polyacetylenes, poly[(R)- 1p ], poly[(R)- 1m ], and poly[(S)- 2p ] were confirmed by SEC and the presence of a Raman scattering peak based on the alternating double bonds of the main chain. Pd-based poly[(R)- 1m ] exhibited CD signals around 350 nm assignable to a certain secondary structure, while Mo-based poly[(R)- 1m ] did not. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3011–3016 相似文献
148.
Atmospheric pressure waves are a notable phenomenon associated with explosive volcanic eruptions. They can provide us with information about eruption processes that are useful both scientifically and practically. In this paper, we give a brief review of studies that have been carried out on this phenomenon in the field of volcanology. Then, we introduce a prototype tool called ‘MOVE’ (Mobile Observatory for Volcanic Explosions). It is a remote-controlled vehicle carrying various instruments to observe pressure waves and the eruption processes.
PACS 91.40.Dr · 91.40.Ft · 93.65.+e · 93.85.+qThis paper was based on work presented at the 2nd International Symposium on Interdisciplinary Shock Wave Research, Sendai, Japan on March 1–3, 2005. 相似文献
149.
Fumihiro Gobo Takehiro Goto Tengfa Long Shu Yin Tsugio Sato 《Research on Chemical Intermediates》2011,37(2-5):211-217
Micro-disks and micro-rods of ZnO were successfully synthesized by a mild solution process using zinc chloride as starting material. The morphology of the ZnO crystals changed substantially, depending on the concentrations of the Zn2+ ion and organic additives in the solution. A plate-like Zn5(OH)8Cl2·H2O precursor with a layered structure could be produced in solutions with high concentrations of chloride ions. The thermal stability, including phase composition and morphology, of the as-prepared Zn5(OH)8Cl2·H2O in air and water was investigated. 相似文献
150.
G. Gergely S. Gurban M. Menyhard A. Jablonski J. Zemek K. Goto 《Surface and interface analysis : SIA》2011,43(11):1365-1370
Electron spectra are generally presented in arbitrary units. The experimental elastic peak intensity Iespec(E) is determined by the elastic backscattering probability Ie(E) of electrons backscattered elastically within the solid angle of the spectrometer. The experimental elastic peak Iespec(E) is converted to Ie(E) backscattering probability using our new procedure based on the Goto ie(E) elastic backscattering current database. The elastic backscattering probability Ic(E) was calculated applying the EPESWIN software of Jablonski. Ie(E) < Ic(E) due to the surface losses of electrons, characterized by the surface excitation parameter Pse (SEP). Pse(E) was determined experimentally using the Goto database and the relationship of Tanuma. Our new procedure is applied to angular‐resolved (AREPES) spectra of Jablonski and Zemek presented in arbitrary units. In their AREPES experiments, the experimental elastic peak intensity Iespec = Ie(E, αd, ΔΩ) was measured at αd angle of detection (35–74°) with a small HSA, with ΔΩ solid angle. The experimental value at 42° $I_{e}(E, {\it{42}}\deg{\hbox{}}, {\Delta}\Omega)$ was converted to probability with the Goto database. It was corrected with a SEP parameter Pse, determined by trial and error method for Si, Ni, Cu and Ag for E = 0.5 and 1 keV primary energies. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献