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1.
2.
基于Gross-Pitaevskii方程,运用有效化学势概念,研究了囚禁在组合势(由磁阱和三维光 晶格组成)中玻色凝聚气体在三维光晶格中的分布规律,并由此得到玻色凝聚气体的归 一化基态波函数.在取消组合势和仅取消光晶格而保留磁阱的两种情况下,运用传播子方 法求解出玻色凝聚气体密度分布的解析表达式.取消组合势后,理论计算所得到的玻色凝聚 气体聚随时间的演化规律与Greiner等的实验结果相一致.仅取消光晶格而保留磁阱时,研 究表明玻色凝聚气体的干涉模式呈现周期性的振荡行为.此外,在磁阱为各向异性的情况下 ,
关键词:
玻色凝聚气体
磁阱
光晶格
干涉模式 相似文献
3.
Paul阱内的压缩效应与量子跃迁 总被引:1,自引:1,他引:0
处理一个一维Paul阱系统中的压缩现象与量子跃迁现象,对于阱内的最强压缩态和共振跃迁(一种极不稳定状态)之间的关系作了阐述,并对利用压缩性质在阱内进行精密测量的可能性作了讨论 相似文献
4.
5.
Europium (Eu+) ions were confined in a Paul trap and detected by non-destructive method. Storage time of Eu+ ions achieved in vacuum was improved by orders of magnitude employing buffer gas cooling. The experimentally detected signal
was fitted to the ion response signal and the total number of ions trapped was estimated. It is found that the peak signal
amplitude as well as the product of FWHM and the peak signal amplitude is proportional to the total number of trapped ions.
The trapped ion secular frequency was swept at different rates and its effect on the absorption line profile was studied both
experimentally and theoretically. 相似文献
6.
Ferhat Sametoglu 《Optical Review》2006,13(5):326-337
Traceability in illuminance measurements at the National Metrology Institute of Turkey (TüBITAK-UME) was established in 2003
with a detector-based realization. The new measurement technique was developed for the determination of illuminance responsivity
and upgrating of the illuminance scale. The unit of the illuminance responsivity, in A/lx, was measured with an expanded uncertainty
of 0.2% (k = 2) by supplying using the developed scanning technique for the calculation of color correction factor. The surface of a
radiometer was scanned using a double-monochromator facility upgraded with an x-y scanning system. The illuminance responsivity
as a function of bandpass and temperature were also investigated in this study.
To use a radiometer in the photometric applications of metrology, a light-sensitive device, a so-called trap detector, was
characterized by measuring the absolute responsivity, the non-linearity, and spatial non-uniformity. 相似文献
7.
Takayuki Sakaguchi 《Optical Review》2003,10(3):136-139
We have succeeded in the operation of rotating a fine particle which was held without mechanical contact by circularly polarized laser beams with opposite propagation directions. A polystyrene latex particle 11.9 μm in diameter deformed in a disk-like shape was dispersed in water, and was trapped using the anti-parallel collinear laser beams which were set up so that they had the circular polarization rotating in the same direction. It was observed that the trapped particle rotated in the same direction as the rotation of the circular polarization of light. Inversion of the rotational direction of the circular polarization of light reversed the direction of the rotation of the particle. Although the rotational speed of a particle varied significantly from particle to particle, it was found to be proportional to the laser beam intensity. A typical value for the rotational speed per beam intensity was 2.1 Hz/W. 相似文献
8.
9.
F. Herfurth K. Blaum S. Eliseev O. Kester H.-J. Kluge S. Koszudowski C. Kozhuharov G. Maero D. Neidherr W. Quint S. Schwarz S. Stahl G. Vorobjev 《Hyperfine Interactions》2006,173(1-3):93-101
A decelerator will be installed at GSI in order to provide and study heavy nuclei without or with only few electrons at very
low energies or even at rest. Highly-charged ions will be produced by stripping at relativistic energies. After electron cooling
and deceleration in the Experimental Storage Ring (ESR) the ions are ejected out of the storage ring at 4 MeV/u and further
decelerated in a combination of linear accelerator structures operated in reverse. Finally, they are injected into a Penning
trap where the ions are cooled to 4 K by electron cooling in combination with resistive cooling. From here, the ions can be
transferred in a quasi DC or in a pulsed mode to different experimental setups. This article describes the technical concepts
of this project focused on the Penning trap.
相似文献
10.
对短程飞行时间法(tim e-of-flight,TOF)中推算冷原子温度的理论拟合公式与近似拟合公式进行了误差分析与比较。研究表明:对于使用短程飞行吸收光谱信号推测冷原子团温度,当探测光光斑半径与冷原子团高斯半径之比k小于0.2时,理论拟合公式和近似拟合公式能很好的相符,随着探测光光斑半径与冷原子团高斯半径比值的逐渐增大,用近似拟合公式所得TOF吸收信号与用理论拟合公式所得TOF吸收信号的误差也将逐渐增大,当比值为0.5时,用近似拟合公式所得TOF吸收信号的误差将增大到20%。 相似文献