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991.
For open systems described by the quantum master equation (QME), we investigate the excess entropy production under quasistatic operations between nonequilibrium steady states. The average entropy production is composed of the time integral of the instantaneous steady entropy production rate and the excess entropy production. We propose to define average entropy production rate using the average energy and particle currents, which are calculated by using the full counting statistics with QME. The excess entropy production is given by a line integral in the control parameter space and its integrand is called the Berry–Sinitsyn–Nemenman (BSN) vector. In the weakly nonequilibrium regime, we show that BSN vector is described by \(\ln \breve{\rho }_0\) and \(\rho _0\) where \(\rho _0\) is the instantaneous steady state of the QME and \(\breve{\rho }_0\) is that of the QME which is given by reversing the sign of the Lamb shift term. If the system Hamiltonian is non-degenerate or the Lamb shift term is negligible, the excess entropy production approximately reduces to the difference between the von Neumann entropies of the system. Additionally, we point out that the expression of the entropy production obtained in the classical Markov jump process is different from our result and show that these are approximately equivalent only in the weakly nonequilibrium regime. 相似文献
992.
Nomoto Tetsuya Imajo Shusaku Yamashita Satoshi Akutsu Hiroki Nakazawa Yasuhiro Krivchikov Alexander I. 《Journal of Thermal Analysis and Calorimetry》2019,135(5):2831-2836
Journal of Thermal Analysis and Calorimetry - We newly constructed a thermal conductivity measurement system for single crystals of molecular compounds. This system enables us to measure the... 相似文献
993.
994.
A partial isothermal ternary phase diagram of the Cd–Mg–Y system including icosahedral quasicrystal (i-QC) and 1/1 approximant (APP) was obtained at 673?K. The stability of the i-QC and APPs in terms of composition and temperature was studied, as a result of which the 2/1 APP phase was discovered at 773?K. Moreover, the i-QC phase was found to be stable at lower Y concentrations of ~12–13?at.%, as compared to the 1/1 APP, which showed ~15–16?at.% Y. Single i-QC, 2/1 and 1/1 APP grains were also synthesized applying centrifuging system. Electron backscatter diffraction (EBSD) characterization of the obtained i-QC and APPs revealed almost the same Kikuchi patterns for the i-QC and 2/1 APP, indicating high resemblance of their structures. However, the Kikuchi pattern acquired from the 1/1 APP was distinguishable from the one obtained from the i-QC as it showed split bands. The occurrence of the split bands was associated with significant deviation from a perfect icosahedral symmetry. This was also confirmed by analysing calculated electron diffraction and Kikuchi patterns along pseudo-five-fold axes of the 2/1 and 1/1 APPs. Finally, orientation relationships between the i-QC, 1/1 APP and α-Mg were investigated by analysing acquired EBSD Kikuchi patterns from the respective domains. Accordingly, three perpendicular two-fold axes of the i-QC and {100} axes of the 1/1 APP occur along three mutually orthogonal {0001}, {10-10} and {11-20} axes of the α-Mg. 相似文献
995.
996.
Probe electrospray ionization of mixture solutions using metal needles with different tip conditions
Satoshi Ninomiya Shunpei Iwamoto Lee Chuin Chen Kenzo Hiraoka 《Surface and interface analysis : SIA》2019,51(1):100-104
Time-dependent mass spectra of mixture solutions of cytochrome c and cholesterol were measured by probe electrospray ionization (PESI) mass spectrometry and the PESI characteristics for several metal needles were investigated with different tip conditions. For a mixture solution of cytochrome c and cholesterol in 0.1% formic acid methanol/water (1/1) at a motion frequency of 1 Hz, an acupuncture needle with a sharp tip and 0.5-mm-diameter titanium and stainless-steel wire needles gave strong cytochrome c and extremely weak cholesterol ion signals. When the frequency was lowered, and the high-voltage duration increased, the titanium and stainless-steel needles provided both cytochrome c and cholesterol ion signals with high intensities well separated over time. 相似文献
997.
998.
Kota Miyata Satoru Yasuda Takuto Masuya Satoshi Ito Yusuke Kinoshita Hitoshi Tamiaki Toru Oba 《Tetrahedron》2018,74(27):3707-3711
Iodination of protoporphyrin IX dimethyl ester using phenyliodine bis(trifluoroacetate) (PIFA) and I2 was studied. Iodine added to both the C3- and C8-vinyl groups equally to afford the iodohydrin or iodoether in the presence of water or alcohol, respectively. Any meso-hydrogen atom was not substituted by an iodine atom under these conditions, although both the vinyl group and one of the meso positions of methyl pyropheophorbide-a bearing a chlorin π-system, a chlorophyll-a derivative, was modified with PIFA and I2. The reaction intermediates derived from the porphyrin were more reactive than those from the chlorin and liable to form intermolecular linkages. The obtained 2-iodo-1-hydroxyethyl group was transformed into a formyl group by a mild treatment. The corresponding iodoether moiety was readily converted into the acetyl group under basic conditions. These transformations were also applicable to smaller olefins such as styrene. 相似文献
999.
1000.
This paper proposes a combined method for two-dimensional temperature and velocity measurements in liquid and gas flows using
temperature-sensitive particles (TSPs), a pulsed ultraviolet laser, and a high-speed camera. TSPs respond to temperature changes
in the flow and can also serve as tracers for the velocity field. The luminescence from the TSPs was recorded at 15,000 frames
per second as sequential images for a lifetime-based temperature analysis. These images were also used for the particle image
velocimetry calculations. The temperature field was estimated using several images, based on the lifetime method. The decay
curves for various temperature conditions fit well to exponential functions, and from these the decay constants at each temperature
were obtained. The proposed technique was applied to measure the temperature and velocity fields in natural convection driven
by a Marangoni force and buoyancy in a rectangular tank. The accuracy of the temperature measurement of the proposed technique
was ±0.35–0.40°C. 相似文献