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991.
Reference electrodes for room temperature ionic liquid (RTIL) applications were constructed that have a known and reproducible potential versus the ferrocene/ferrocenium couple. They are based on reference electrodes of the first kind, Ag/Ag+ couple type, or of the second kind, based on Ag/AgCl in M+Cl?. The former uses AgNO3 salt and the latter tetrabutylammonium chloride, Bu4NCl, dissolved in acetonitrile which are then introduced to the ionic liquid of choice for a final concentration of 0.1 M. The reference electrodes can be easily and reproducibly constructed. An ionic contact of these reference systems with the test electrolyte was made using an asbestos fiber liquid junction. The internal compartment of the reference system was filled with the same ionic liquid as used for the electrochemical experiment. The performance of these reference electrodes was tested in selected ionic liquids using the ferrocene/ferrocenium redox couple. The stability, reproducibility, and temperature behavior of the two reference systems have been characterized in the following ionic liquids: 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIBF4), 1‐butyl‐3‐methylimidazolium bis(trifluoromethanesulfonyl)imide (BMI(CF3SO2)2N), and 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIPF6). It has been found that the formal potentials of the examined reference systems are stable over several days. There is a linear relationship for the temperature studied in the range from 25 to 60 °C. 相似文献
992.
Current (I)–voltage (V) characteristic under oxygen potential gradients was experimentally examined on single crystal BaTiO3−δ in its mixed ion/electron/hole regime at 1000 °C. The variation of I vs. V appears similar to that of an n/p junction, but with the limiting slope (dI/dV) approaching the maximum and minimum possible equilibrium conductances in the given oxygen potential gradient as increasing forward and reverse bias, respectively. This characteristic has been precisely traced theoretically by using the partial ionic and electronic conductivities of BaTiO3−δ as measured against uniform oxygen chemical potential in equilibrium state. The nonlinear characteristic is attributed to the redistribution of oxygen chemical potential that is caused by a non-vanishing gradient of the ionic transference number of the oxide under the given oxygen potential gradient. It is demonstrated that the bulk transport properties of a mixed conductor may be tailored by terminal voltage in a chemical potential gradient. 相似文献
993.
在电子和激发态原子散射的物理过程中,靶的连续态是非常重要的通道,我们使用等价局部光学势模型计算了从电离阈值到200eV能量范围的氦的23S亚稳态的电离截面,并同实验结果作了比较。 相似文献
994.
N=2超对称量子力学的新实现 总被引:2,自引:2,他引:0
研究了N=4一维超对称量子力学的一种新的实现,并讨论了若干实例。 相似文献
995.
996.
997.
Biman Bagchi 《Journal of Chemical Sciences》1987,99(4):243-252
The canonical average of the Boltzmann factor of the interaction potential, as measured by a test particle, is shown to be
equal to the inverse of the fraction of the average number
of 1-particle Mayer clusters. The potential distribution theory is used to derive an analytic expression for a mean number
of small clusters
1≤n<N, in anN-particle system) in the mean-field expression. Near the spinodal density, the average number of small clusters undergo a
sharp change. Computation of pressure shows that only the first four clusters produce surprisingly good agreement with known
pressure even beyond the spinodal density.
Contribution No. 439 from the Solid State and Structural Chemistry Unit 相似文献
998.
The effect of replacing the hydrogen atoms in thioformaldehyde by halogen atoms (F, Cl) on the ionisation potential of the
non-bonding electron is analysed by using the Hellman-Feynman theorem, regarding the nuclear charge of the substituent as
a parameter in the many-electron Hamiltonian. The trends predicted by our theory nicely agree with the relevant ionisation
potentials computed either by applying Koopmans’ theorem or by the ΔE
SCF method. For the carbonyls, avaible experimental data indicate the reliability of our prediction. 相似文献
999.
R. Syski 《Stochastic Processes and their Applications》1977,5(2):93-129
A Markov chain (with a discrete state space and a continuous parameter) is perturbed by forcing a chain to return to “permissible” states whenever it happens to enter “forbidden” states, with returns governed by a replacement distribution.The compensation method is employed to obtain the distribution for the modified chain, in terms of the original chain and the perturbation mechanism.Emphasis is placed on ergodic chains, and interpretation of results in terms of perturbation theory of semi-groups and the ergodic potential theory (based on the fundamental matrix of a chain) is mentioned. 相似文献
1000.
We have developed a kinematical theory for the asteroidal belt and Kirkwood gaps from the point of view of stellar dynamics.
We have generated the potential that would produce these gaps and have made a spectral analysis study. We have shown that
these gaps could be due to spiral tubes of matter in the ecliptic plane as a consequence of differential rotation and spatial
interference of density waves. We have also shown that this mechanism could account for depletion of matter from this region. 相似文献