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971.
Humidity Effect on Toluene Decomposition in a Wire-plate Dielectric Barrier Discharge Reactor 总被引:1,自引:0,他引:1
Guo Yu-fang Ye Dai-qi Tian Ya-feng Chen Ke-fu 《Plasma Chemistry and Plasma Processing》2006,26(3):237-249
Laboratory-scale experiments were performed to evaluate the humidity effect on toluene decomposition by using a wire-plate dielectric barrier discharge (DBD) reactor at room temperature and atmospheric pressure. The toluene decomposition efficiency as well as the carbon dioxide selectivity with/without water in a gas stream of N2 with 5% O2 was investigated. Under the optimal humidity of 0.2% the characteristics of toluene decomposition in various background gas, including air, N2 with 500 ppm O2, and N2 with 5% O2 were observed. In addition, the influence of a catalyst on the decomposition was studied at selected humidities. It was found that the optimum toluene removal efficiency was achieved by the gas stream containing 0.2% H2O, since the presence of water enhanced the CO2 selectivity. In addition, the toluene removal efficiency increased significantly in a dry gas stream but decreased with an increase in the humidity when the Co3O4/Al2O3/nickel foam catalyst was introduced into the discharge area. 相似文献
972.
Ulrich Stumper 《International Journal of Infrared and Millimeter Waves》1981,2(5):999-1014
A measuring system including an oversized cavity resonator operating in the TE01 mode for the determination of the complex permittivity - j of low-loss liquids at frequencies of about 36 GHz is described. While is obtained by wavelength measurements in the filled and the empty resonator, is determined from the variation of the Q factor of the filled resonator with the length of the dielectric sample. The Q factors of values of about 2·104 to 105 can be measured automatically by means of a desk calculator which controls the frequency and collects the digitized values of the detector output voltage. By means of the calculator, the Q factors of the resonator are determined by fitting analytical (Lorentzian) resonance curves to the measurement data. and the Q factor for zero sample length are calculated according to Göttmann's methods. 相似文献
973.
The IR polarized spectra of gypsum CaSO4·2H2O were recorded at incidence angles of approximately 10 and 16 degrees. Band singlet or doublet was observed for the higher frequency ν3(SO42−) mode of Bu symmetry type, depending on polarization (n or p). A doublet was observed for the lower frequency ν3(SO42−) mode of Bu symmetry type too, irrespectively of the type of polarization. In order to give an explanation for the doublets origin, a model permittivity function was constructed. Quite good agreement exists between the reflectance based on the model permittivity function and the experimentally measured one for the high-frequency doublet. The origin of the lower frequency doublet could not be explained in this way, but may be speculated to result from an Evans type interaction between a combination of a water libration and ν2(SO42−), with the lower frequency ν3(SO42−) mode. 相似文献
974.
计算拟合了26种块体材料的能量损失函数,包括18种单质材料(Ag、Al、Au、C、Co、Cs、Cu、Er、Fe、Ge、Mg、Mo、Nb、Ni、Pd、Pt、Si、Te)和8种化合物(AgCl、Al2O3、AlAs、CdS、SiO2、ZnS、ZnSe、ZnTe).基于Drude-Lindhard模型,将实验测得的能量损失函数拟合为有限个解析函数,通过求和规则验证了拟合结果的准确性.基于拟合结果,模拟了反射电子能量损失谱,模拟结果与实验结果一致.所有材料能量损失函数的拟合参数均在线公开,地址为http://micro.ustc.edu.cn/ELF/ELF.html. 相似文献
975.
Mustafa Okumuş 《Molecular Crystals and Liquid Crystals》2016,625(1):117-125
The 6CB/8CB/8OCB liquid crystal mixture has been studied by Differential Scanning Calorimetry (DSC), polarised optic microscopy (POM), Semiconductor Characterization System, and Ultra-violet spectrophotometry (UV). DSC and POM results indicate that the 6CB/8CB/8OCB mixture exhibits liquid crystalline properties. The capacitance-voltage and conductance-voltage measurements were performed in the frequency range of 200-500 kHz and in the temperature range of 30oC–50oC. The 6CB/8CB/8OCB mixture showed an extremely large positive dielectric anisotropy. The molar absorptivity ? for the 6CB/8CB/8OCB mixture was calculated and found to be higher than the absorptivity values of the binary mixtures due to the alkyl chain length with H-aggregation. 相似文献
976.
In the present study, we report the dielectric behavior of a high temperature nematic liquid crystal (NLC) in both the planar as well as homeotropic alignments. To understand the mechanism of such high temperature NLC, we have performed dielectric spectroscopy in frequency range 100 Hz to 10 MHz. The different dielectric parameters, viz., effective dielectric permittivity and dielectric anisotropy of the sample have been determined with the variation of frequency and temperature. It is found that the dielectric parameters depend on dipole moment and rotation of side chain of molecule. The phase transition of this high temperature NLC has been confirmed by the DSC study. 相似文献
977.
We have synthesized the composition x = 0.01 of the (Sr1-xLax)2(Ta1-xTix)2O7 solid solution, mixing the ferroelectric perovskite phases Sr2Ta2O7 and La2Ti2O7. Related oxide and oxynitride materials have been produced as thin films by magnetron radio frequency sputtering. Reactive sputter deposition was conducted at 750 °C under a 75 vol.% (Ar) + 25 vol.% (N2,O2) mixture. An oxygen-free plasma leads to the deposition of an oxynitride film (Sr0.99La0.01) (Ta0.99Ti0.01)O2N, characterized by a band gap Eg = 2.30 eV and a preferential (001) epitaxial growth on (001) SrTiO3 substrate. Its dielectric constant and loss tangent are respectively Epsilon' = 60 (at 1 kHz) and tanDelta = 62.5 × 10−3. In oxygen-rich conditions (vol.%N2 ≤ 15%), (110) epitaxial (Sr0.99La0.01)2(Ta0.99Ti0.01)2O7 oxides films are deposited, associated to a larger band gap value (Eg = 4.55 eV). The oxide films permittivity varies from 45 to 25 (at 1 kHz) in correlation with the decrease in crystalline orientation; measured losses are lower than 5.10−3. For 20 ≤ vol.% N2 ≤ 24.55, the films are poorly crystallized, leading to very low permittivities (minimum Epsilon' = 3). A correlation between the dielectric losses and the presence of an oxynitride phase in the samples is highlighted. 相似文献
978.
Strong light‐matter coupling between a molecular vibrational mode in a PMMA film and a low‐loss mid‐IR microcavity 下载免费PDF全文
Merav Muallem Alex Palatnik Gilbert D. Nessim Yaakov R. Tischler 《Annalen der Physik》2016,528(3-4):313-320
Microcavity devices exhibiting strong light‐matter coupling in the mid‐infrared spectral range offer the potential to explore exciting open physical questions pertaining to energy transfer between heat and light and can lead to a new generation of efficient wavelength tunable mid‐infrared sources of coherent light based on polariton Bose‐Einstein Condensation. Vibrational transitions of organic molecules, which often have strong absorption peaks in the infrared and considerably narrower linewidths than organic excitonic resonances, can generate polaritonic states in the mid‐infrared spectral range using microcavity devices. Here, narrow linewidth polaritonic resonances are exhibited in the mid‐infrared by coupling the carbonyl stretch vibrational transition of a polymethyl methacrylate film to the photonic resonance of a low optical‐loss mid‐infrared microcavity, which consisted of two Ge/ZnS dielectric Bragg reflectors. Rabi‐splitting of 14.3 meV is observed, with a 4.4 meV polariton linewidth at anti‐crossing. The large Rabi‐splitting relative to linewidth indicates efficient impedance‐matching between the bare vibrational and photonic states, and suggests molecular‐vibration polaritons incorporated in dielectric microcavities can be an enabling step towards realizing polariton optical switching and polariton condensation in the mid‐infrared spectral range. 相似文献
979.
980.
The enhancement of the oxidation resistance of carbonyl iron by polyaniline coating and consequent changes in electromagnetic properties 总被引:1,自引:0,他引:1
Madina A. Abshinova Petr Sáha Jana Ková?ová 《Polymer Degradation and Stability》2008,93(10):1826-1831
In order to enhance the stability of commercially unmodified processed carbonyl iron (CI) and to prevent corrosion, CI powders were coated with polyaniline (PANI) by using surfactant-stabilized PANI colloids in chloroform. PANI coats the individual particles with a film of a few micrometres thickness. Electromagnetic properties, as well as thermal and storage stability, of polymer composites filled with pristine and PANI-coated CI have been studied. The PANI overlayer has negligible influence on the magnetic and dielectric spectra of CI-filled polymer composites at ambient temperature. However, the temperature-frequency study of complex permittivity demonstrated that the composites containing PANI-coated CI powders are characterized by temperature-independent dielectric spectra, whereas the complex permittivity of polymer composites with pristine powders drastically decreased at elevated temperature. Additionally, the thermogravimetric analysis of pristine and PANI-coated CI powders in air has shown improvement in the stability. PANI overlayer prevents the oxidation of particles and acts as corrosion protection of CI. 相似文献