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101.
H. K. Lee C. S. Ho M. Hu B. Tomlinson C. K. Wong 《Biomedical chromatography : BMC》2013,27(11):1369-1374
A sensitive and specific liquid chromatography tandem mass spectrometric method was developed and validated for the simultaneous determination of rosuvastatin (ROS) and N‐desmethyl rosuvastatin (NOR‐ROS) in human plasma using deuterium‐labeled internal standards. The plasma samples were prepared using liquid–liquid extraction with diethyl ether. Chromatographic separation was accomplished on an Xterra MS C18 column. The mobile phase consisted of a gradient mixture of 15 µmol/L ammonium acetate in water and in methanol, maintained at a flow rate of 0.4 mL/min. Mass spectrometric detection was carried out in negative electrospray ionization mode and monitored by quantification and qualification transitions for each analyte. Using 300 μL plasma samples, the lower limits of quantification of ROS and NOR‐ROS were 0.05 and 0.02 µg/L respectively. The linearity of ROS and NOR‐ROS ranged from 0.05 to 42 and 0.02 to 14 µg/L respectively. The relative standard deviations of ROS and NOR‐ROS were <13 and 9%, respectively, while the deviations from expected values were within ?4.7–9.8 and ?5.2–4.6%, respectively. The present method offered high sensitivity and was successfully applied to a 24 h pharmacokinetic study of ROS and NOR‐ROS in healthy subjects receiving a single dose of 10 mg ROS. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
102.
Polarized laser Raman studies of biological polymers 总被引:1,自引:0,他引:1
B Fanconi B Tomlinson L A Nafie W Small W L Peticolas 《The Journal of chemical physics》1969,51(9):3993-4005
103.
Organic materials have been shown to be quite useful for the fabrication of integrated-optics devices. The fabrication of low loss (0.1 dB cm?1) sheet-film waveguides and studies of high gain (100 dB cm?1) thin-film laser amplifiers and oscillators are reviewed. Techniques employing photosensitive components have made it possible to make three-dimensional waveguides which have the lowest losses reported so far (0.2 dB cm?1 in single-mode structures). Surface and index gratings and related devices made with organic materials are also discussed. 相似文献
104.
M. V. Yakushev H. Neumann R. D. Tomlinson P. Rimmer G. Lippold 《Crystal Research and Technology》1994,29(3):417-426
Copper deficient p-type conducting CuInSe2 single crystals were implanted with 40 keV protons in the fluence range from 2.5 · 1014 to 1.5 · 1016 cm−2. Over the whole fluence range the implanted layers were n-type conducting which is ascribed to passivation of the acceptors due to copper vacancies and formation of donors by hydrogen atoms located at interstitial positions. The thermal stability of the conductivity changes due to proton implantation is limited to temperatures below 100 °C. 相似文献
105.
C. Tomlinson 《Mikrochimica acta》1961,49(3):457-466
Summary The conditions required in the thermoelectric microdetermination of molecular weight have been investigated, and determinations using the modified procedure resulted in a standard deviation of 1.9% in the range 100–700.
Zusammenfassung Die bei der thermoelektrisehen Mikrobestimmung des Molekulargewichtes einzuhaltenden Bedingungen wurden untersucht. Bestimmungen nach dem modifizierten Verfahren zeigten in dem Gebiet zwischen 100 und 700 eine Standardabweichung von 1,9%.
Résumé On a étudié les conditions exigées pour la microdétermination thermoélectrique du poids moléculaire. En apportant des modifications au procédé, les résultats obtenus présentent un écart-type de 1,9% dans le domaine 100–700.相似文献
106.
H. Neumann W. Kissinger H. Sobotta V. Riede R. D. Tomlinson N. Avgerinos 《Czechoslovak Journal of Physics》1984,34(1):69-77
Infrared reflectivity and absorption spectra of CuInS2 are measured in the wave-number range from 180 to 700cm–1for the polarization directions perpendicular and parallel to the tetragonalc axis of the crystals. The optical dispersion parameters of the fundamental lattice modes are determined for both polarization directions and compared with previously published data. All the structures observed in the absorption spectra in the wavenumber range beyond the fundamental lattice bands can be interpreted in terms of two-phonon combination modes due to zone-centre phonons. 相似文献
107.
Tlach BC Tomlinson AL Bhuwalka A Jeffries-El M 《The Journal of organic chemistry》2011,76(21):8670-8681
In an effort to design new electron-deficient building blocks for the synthesis of conjugated materials, a series of new trans-benzobisoxazoles bearing halogen or alkynyl substituents at the 4,8-positions was synthesized. Additionally, the impact of these modifications on the optical and electronic properties was investigated. Theoretical calculations predicted that the incorporation of various alkynes can be used to tune the energy levels and band gaps of these small molecules. The targeted 4,8-disubstituted benzobisoxazoles were easily prepared in good yields using a two-step reaction sequence: Lewis acid catalyzed orthoester cyclization followed by Sonogashira cross-coupling. The experimentally determined HOMO values for these 4,8-disubstituted benzobisoxazoles ranged from -4.97 to -6.20 eV and showed reasonable correlation to the theoretically predicted values, with a percent deviation that ranged from 2.4-12.8%. However, the deviation between actual and predicted HOMO values was reduced to less than 3.5% when the theoretical values were extrapolated to the long-chain limit and compared to copolymers containing the 4,8-disubstituted benzobisoxazoles. Collectively, these results indicate that these 4,8-disubstituted trans-benzobisoxazoles can be used for the synthesis of new conjugated materials with electronic properties that are variable and predictable. 相似文献
108.
The free energies of mixing for molten indium-antimony, cadmium-antimony, indium-bismuth, lead-bismuth and tin-bismuth were calculated from the variation of electrical resistivity with composition employing the model of Takeuchi and Endo. Resistivities measured in this laboratory with an electrodeless technique for In-Sb alloys, together with published values for Cd-Sb, In-Bi, Pb-Bi and Sn-Bi alloys were used in the calculations. Evaluation of the resistivity data gave the composition dependence of the derivatives of the chemical potentials of the constituents and the integral molar free energies of mixing. No assumptions regarding ideal entropy were made to obtain these free energy values although a statistically random mixture of ions is presumed in the scattering model. Conclusions drawn from a comparison between the calculated free energy values and published thermodynamic data for these systems are discussed in terms of departures from regularity and the variations in the effective free electron concentration. 相似文献
109.
110.