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961.
962.
用多光束干涉模拟晶格图案 总被引:2,自引:2,他引:0
利用多束激光干涉,可形成三维晶格结构,计算结果指出,用四束光或六束光可形成大部分的布拉格(Bragg)点阵。同时用He-Ne激光器获得了体心正方和面心立方的相干图案,晶格常数和计算结果相符,该研究对构成可见和红外区域的光子晶有一定意义。 相似文献
963.
宽带飞秒脉冲双折射干涉滤波的研究 总被引:1,自引:1,他引:0
对宽带飞秒脉冲双折射干涉滤波进行了理论和实验研究。首先给出了一种新型的双折射干涉滤波器的原理和设计,得到了输出滤波光谱强度分布的解析表达式。然后进行了15fs宽带脉冲的干涉滤波的实验研究,实验得到了一组性能良好的透射和反射输出的干涉滤波谱图,实验测量与理论计算基本一致。同时还分析了群速失配以及色散对宽带飞秒脉冲双折射干涉滤波的影响。结果表明这种滤波器对宽带飞秒脉冲有很好的干涉滤波作用,能同时前向透射和侧向反射干涉滤波输出,且无插入功率损耗,可以用来获得波长稳定的多波长可调谐超短脉冲光源。对于飞秒脉冲干涉滤波器的设计和应用具有重要的参考价值。 相似文献
964.
965.
利用环形腔掺钛宝石激光自动扫描系统、公里级怀特池系统和信号探测系统,我们对氧分子A带重叠谱线区(13162.85~13165.33cm ̄(-1))进行了高分辨吸收光谱测量,给出了8条谱线的线宽、线强的实验值。同时通过对测量数据的分析,首次证明在谱线重叠区,谱线之间的线相干效应不仅影响谱线之间的吸收率,而且同样影响线参数测量值的精度。在0.1MPa与光程为1km时,它对线强、线宽的测量值和透过率的最大影响分别可达8.8%、16.6%和8.3%。 相似文献
966.
J P Vigier 《Pramana》1985,25(4):397-418
The differences between Einstein and Bohr on the interpretation of quantum mechanics revolved around the question of completeness
of the Copenhagen Interpretation. This fundamental problem is examined here in the light of recent neutron interference experiments
which allow for novel experimental situations. Exploiting the possibility of neutron spin flip in these experiments, the inadequacy
of the Copenhagen interpretation to fully understand the experimental results is brought out. Instead a causal interpretation
of quantum mechanics is advocated, in which the neutron, as a particle, does always have a definite space time trajectory
but also involves a wave which creates a potential affecting the particle neutron. The reestablishment of definite particle
trajectories in the microscopic domain obliges us to reexamine the statistical treatment of ‘identical’ particles, as well
as the problem of negative energies and probabilities in relativistic quantum mechanics. 相似文献
967.
石墨炉原子吸收光谱法测定饮料中的锗及基体干扰的研究 总被引:4,自引:0,他引:4
本实验以硝酸镍为基体改进剂,用塞曼石墨炉原子吸收法测定样品中的微量锗,研究了溶液介质与共存元素对测定的影响。方法简便,准确快速,灵敏度高。 相似文献
968.
Hiroyo Segawa Kazuaki Yoshida Toshiaki Kondo Shigeki Matsuo Hiroaki Misawa 《Journal of Sol-Gel Science and Technology》2003,26(1-3):1023-1027
We report on a fabrication of photonic crystal structures in organic-inorganic hybrid films by a laser interference technique. Films containing the methacrylic group, which is photopolymerable by an adequate laser light, are prepared using a sol-gel technique from a mixture of organosilicate alkoxide and zirconium alkoxide modified by methacrylic acid. For the photopolymerization, the coated films on glass substrate are exposed to the interference light which is arranged with a square lattice in about 1 m spacing. From microscopic images of microstructures produced by the photopolymerization, the influence of changes in conditions such as pre-bake temperature, photoinitiator and irradiation energy (laser power and duration time) on periodic structure is investigated. Adjusting the conditions, 2D and 3D photonic crystal structures with the micrometer-order period are formed in organo-silicate-zirconate hybrid materials. 相似文献
969.
N.J. Arfsten A. Eberle J. Otto A. Reich 《Journal of Sol-Gel Science and Technology》1997,8(1-3):1099-1104
Angle-dependent dip coating (ADDC) is a modified dip coating technique that offers advantages for the production of optical
interference filters. In contrast to conventional dip coating (DC), the substrate is withdrawn from the coating solution under
an angle of inclination. Thereby, the two surfaces of the substrate are coated with individual film thicknesses. An experimental
setup for ADDC has been built and the decisive process influences on coating thicknesses have been evaluated. In order to
gain full control over the individual layer thicknesses, reaching from 20 nm to 160 nm, it is necessary to vary the following
process parameters: lifting speed, angle of inclination and concentration of the dipping solution. The results of coating
experiments prove the advantages of ADDC over DC. A first example aims at reducing the number of coating steps: an ADDC long
pass filter produced in 10 coating steps reaches the same optical performance as a conventional DC filter made in 16 steps.
A second example demonstrates the possibility to improve quality: a commercial DC beam splitter can be improved with respect
to the flatness of transmission and reflection curves when being produced in 4 steps by ADDC instead of 8 steps by DC. Furthermore,
ADDC offers the possibility to fabricate even narrow band pass filters, which are naturally difficult to obtain by conventional
DC. 相似文献
970.