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271.
We present the dynamical phase diagrams of the kinetic Blume–Capel model with random diluted single-ion anisotropy in a square lattice under the presence of a time-varying (oscillating) external magnetic field calculated by an analytical method, the effective-field theory (EFT). The kinetics is modeled with the formalism of a master equation. The time-averaged magnetization (M) acts as the order parameter and divides the temperature–field plane into three regions: ferromagnetic, paramagnetic, and coexistence of ferromagnetic and paramagnetic phases. In addition, the hysteresis loop area and the dynamic correlation function are calculated. It is observed that the inclusion of spin–spin correlations suppress the first-order transition lines and dynamical tricritical points for all values of the crystal-field concentration. 相似文献
272.
In this study, we have analyzed the dynamical phase transitions of spin-1 Blume-Capel model with quenched random crystal field
under the effect of a time dependent oscillating magnetic field. We have obtained the magnetic field, temperature (h,T) cross sections of the global phase diagram for constant values of the concentration and the amplitude of the single-ion
anisotropy within mean field approximation. There are regions of the phase space where both ordered and disordered phases
coexist. In addition, the dynamic phase transition from one regime to the other can be a first- or a second-order depending
on the region in the phase diagram. Hence, the system exhibits a number of interesting phenomena and a rich variety of phase
diagrams with type being according to the concentration p of active local crystal fields. 相似文献
273.
Mustafa Yüksek Hüseyin Ertap Ayhan Elmali H. Gul Yaglioglu Gasan M. Mamedov Mevlüt Karabulut Mustafa K. Öztürk 《Optics & Laser Technology》2012,44(7):2178-2181
We have investigated the structural and optical properties of bulk GaTe crystal grown by vertical Bridgman method. Two photon absorption (TPA) properties of GaTe crystal have been investigated by the open aperture Z-scan technique under 1064 nm wavelength with 4 ns or 65 ps pulse durations. The TPA coefficients are greater in ns regime than that of ps regime. Upon increasing intensity of incident light from 5.02×107 W/cm2 to 1.07×108 W/cm2, the TPA coefficients increased from 3.47×10?6 cm/W to 8.53×10?6 cm/W for nanosecond excitation. Similarly, when intensity of incident light was increased from 6.81×108 W/cm2 to 9.94×108 W/cm2 the TPA coefficients increased from 3.53×10?7 cm/W to 6.83×10?7 cm/W for picosecond excitation. Measured TPA coefficient of GaTe crystal is larger than that of GaSe and GaS layered crystals. 相似文献
274.
J. Gulín-González P. Demontis E. Navas Conyedo G.B. Suffritti 《Journal of Physics and Chemistry of Solids》2012,73(6):797-802
Reversible amorphization and memory effects of both dense and open frameworks have received a great attention due to their prospective industrial applications. In this paper, the results of a computational study related to phase transition and memory effects in AlPO4-5 nanoporous material at high external pressure is presented. The behavior of the AlPO4-5 unit cell at high external pressures was studied by energy minimization techniques using classical potentials. A combination of interatomic potentials was used to describe the crystalline structure of the aluminophosphate. According to simulation's result a decrease of crystalline order is observed at a pressure about 3.5 GPa. The behavior of the simulated infrared spectra of compressed structures is an unambiguous evidence of structural disorder. Also, an abrupt change in the slope of the unit cell volume vs. pressure curve was obtained. At P≤3.5 GPa the process was found reversible. Contrary to what has been reported in other aluminosilicate systems the final crystalline state of AlPO4-5 at the highest simulated pressure was not amorphous. According to our knowledge this is the first evidence of a reversible first-order crystal-crystal phase transition in AlPO- family materials. This result could be important in future industrial and catalytic applications of these materials. 相似文献
275.
276.
Dr. Seetharaman Manojveer Nitish K. Garg Zarif Gul Ayesha Kanwal Dr. Yogesh Goriya Dr. Magnus T. Johnson 《ChemistryOpen》2023,12(1):e202200245
A new class of palladium complexes bearing bidentate 2-hydroxypyridine based ligands have been prepared and fully characterized. The applications of these new complexes towards ketone alkylation reactions with alcohols through a metal-ligand cooperative borrowing-hydrogen (BH) process were demonstrated. 相似文献
277.
Mengying Zhang Ze Zhang Zarmina Gul Mengfei Tian Junling Wang Kaili Zheng Chunjian Zhao Chunying Li 《Journal of separation science》2023,46(15):2300098
In recent years, it has been found that changing ambient conditions (CO2/N2, temperature, pH) can trigger a switchable phase transition of deep eutectic solvents, and such solvents are known as responsive deep eutectic solvents. In this work, we present the development history, properties, and preparation of responsive deep eutectic solvents, followed by the application of responsive deep eutectic solvents in the extraction and separation of bioactive compounds are presented. Importantly, the mechanism of responsive deep eutectic solvents in the extraction of bioactive compounds is discussed. Finally, the challenges and prospects of responsive deep eutectic solvents in the extraction and separation of bioactive compounds are proposed. Responsive deep eutectic solvents are considered green and efficient solvents. Some methods for extraction and separation of bioactive compounds by responsive deep eutectic solvents can increase the possibility of recycling the deep eutectic solvents, and provide higher efficiency in the extraction and separation field. It is hoped that this will provide a reference for the green and sustainable extraction and separation of various bioactive compounds. 相似文献