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61.
利用脉冲直流放电技术制备的Xe原子亚稳态5p56s[3/2]2和5p56s'[1/2]0, 在单光子为28000~42000 cm-1能量范围内, 结合飞行时间质谱技术获得Xe原子5p5np'[3/2]1,[1/2]1和5p5nf'[5/2]3自电离Rydberg态的共振增强激发光谱. 根据Fano线形公式对呈现明显不对称线形的激发谱进行系统地分析,获得系统的能级位置、量子亏损、线性因子、共振宽度、共振态寿命和衰减宽度等数据,其中线形因子和共振宽度相对有效量子数呈线性关系. 另外分析了5p5np'序列的能级间距.  相似文献   
62.
建立吹扫捕集–气相色谱–质谱联用法测定环境水中101种常见挥发性有机物(VOCs)的方法。通过加热吹扫,样品水中的VOCs富集于捕集管中,以DB–624(60 m×0.25 mm,1.4μm)色谱柱分离,内标法定量。结果表明,101种挥发性有机物(VOCs)色谱分离效果良好,质量浓度在0.5~50 ng/mL范围内与色谱峰面积均呈线性关系,高沸点VOCs线性范围较窄。方法定量限(10 S/N)为0.11~0.77 ng/mL,均低于GB 3838–2002《地表水环境质量标准》、GB 5749–2006《生活饮用水卫生标准》及国外相关标准的限值。平均加标回收率在70.3%~123.6%之间,测定结果的相对标准偏差不大于8.8%(n=6)。该方法快速、简便,适用于环境水中挥发性有机化合物的分析检测。  相似文献   
63.
本文针对山西大同大学《泛函分析》课程实施的基于"SPOC+部分翻转课堂"的混合式教学模式的具体实践,为互联网时代高等教育课堂教学改革和教育创新发展提供新思路.  相似文献   
64.
周萍  李熙涵  邓富国  周宏余 《中国物理》2007,16(10):2867-2874
This paper presents a scheme for probabilistic teleportation of an arbitrary GHZ-class state with a pure entangled two-particle quantum channel. The sender Alice first teleports the coefficients of the unknown state to the receiver Bob, and then Bob reconstructs the state with an auxiliary particle and some unitary operations if the teleportation succeeds. This scheme has the advantage of transmitting much less particles for teleporting an arbitrary GHZ-class state than others. Moreover, it discusses the application of this scheme in quantum state sharing.  相似文献   
65.
从磁滞回线了解铁磁性材料的性能   总被引:2,自引:0,他引:2  
从磁滞回线简要讨论了铁磁性材料的性能及特点,并指出一些大学物理教材在这方面讨论的不妥之处.  相似文献   
66.
In general, quantum key distribution (QKD) has been proved unconditionally secure for perfect devices due to quantum uncertainty principle, quantum noneloning theorem and quantum nondividing principle which means that a quantum cannot be divided further. However, the practical optical and electrical devices used in the system are imperfect, which can be exploited by the eavesdropper to partially or totally spy the secret key between the legitimate parties. In this article, we first briefly review the recent work on quantum hacking on some experimental QKD systems with respect to imperfect devices carried out internationally, then we will present our recent hacking works in details, including passive faraday mirror attack, partially random phase attack, wavelength-selected photon-number-splitting attack, frequency shift attack, and single-photon-detector attack. Those quantum attack reminds people to improve the security existed in practical QKD systems due to imperfect devices by simply adding countermeasure or adopting a totally different protocol such as measurement-device independent protocol to avoid quantum hacking on the imperfection of measurement devices [Lo, et al., Phys. Rev. Lett., 2012, 108: 130503].  相似文献   
67.
We propose a theoretical scheme for secure quantum key distribution network following the ideas m quantum aense coding. In this scheme, the server of the network provides the service for preparing and measuring the Bell states,and the users encode the states with local unitary operations. For preventing the server from eavesdropping, we design a decoy when the particle is transmitted between the users. The scheme has high capacity as one particle carries two bits of information and its efficiency for qubits approaches 100%. Moreover, it is unnecessary for the users to store the quantum states, which makes this scheme more convenient in applications than others.  相似文献   
68.
 今年10月2日是我们的老所长和现任名誉所长黄祖洽院士的75岁生日,我和中国物理学界的朋友们一道向这位著名的核物理和理论物理学家,中国核武器理论研究和设计的功臣表示热烈的祝贺。  相似文献   
69.
Halo structures of some light mirror nuclei are investigated with the relativistic mean field (RMF) theory. The calculations show that the dispersion of the valence proton is larger than that of the valence neutron in its mirror nucleus, the difference between the root-mean-square (rms) radius of the valence nucleon in each pair of mirror nuclei becomes smaller with the increase of the mass number A, and all the ratios of the rms radius of the valence nucleon to that of the matter in each pair of mirror nuclei decrease almost linearly with the increase of the mass number A.  相似文献   
70.
This paper presents a simple way for an eavesdropper to eavesdrop freely the secret message in the experimental realization of quantum communication protocol proposed by Beige et al (2002 Acta Phys. Pol. A 101 357). Moreover, it introduces an efficient quantum secure communication protocol based on a publicly known key with decoy photons and two biased bases by modifying the original protocol. The total efficiency of this new protocol is double that of the original one. With a low noise quantum channel, this protocol can be used for transmitting a secret message. At present, this protocol is good for generating a private key efficiently,  相似文献   
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