首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   313篇
  免费   49篇
  国内免费   26篇
化学   4篇
力学   3篇
数学   81篇
物理学   300篇
  2024年   1篇
  2023年   4篇
  2022年   11篇
  2021年   7篇
  2020年   9篇
  2019年   8篇
  2018年   5篇
  2017年   7篇
  2016年   14篇
  2015年   8篇
  2014年   22篇
  2013年   21篇
  2012年   17篇
  2011年   38篇
  2010年   22篇
  2009年   30篇
  2008年   24篇
  2007年   20篇
  2006年   12篇
  2005年   9篇
  2004年   5篇
  2003年   14篇
  2002年   13篇
  2001年   14篇
  2000年   17篇
  1999年   7篇
  1998年   2篇
  1997年   2篇
  1996年   1篇
  1995年   2篇
  1994年   3篇
  1993年   3篇
  1992年   4篇
  1991年   3篇
  1990年   2篇
  1988年   2篇
  1986年   1篇
  1985年   1篇
  1982年   2篇
  1981年   1篇
排序方式: 共有388条查询结果,搜索用时 15 毫秒
1.
陈昌永 《光子学报》2002,31(11):1317-1320
描述了简并V型三能级原子与单模相干态光场的Raman相互作用,获得了处于激发态单态的原子与相干态光场相互作用的结果.利用探测原子与光场的相互作用将原子和光场制备成最大缠结态,并注入待测原子,通过原子与腔模构成的Bell基矢演化,对腔场进行选择性探测,获得探测原子相互作用后可能的量子状态,然后对待测原子与腔场进行联合探测,接着对探测原子的量子状态实施幺正变换,就将探测原子制备到待测原子的初始量子态上,从而实现未知原子态的隐形传送.  相似文献   
2.
A conclusive teleportation protocol of a d-dimensional two-particle unknown quantum state using three d- dimensional particles in an arbitrary pure state is proposed. A sender teleports the unknown state conclusively to a receiver by using the positive operator valued measure(POVM) and introducing an ancillary qudit to perform the generalized Bell basis measurement, We calculate the optimal teleportation fidelity. We also discuss and analyse the reason why the information on the teleported state is lost in the course of the protocol,  相似文献   
3.
According to Bell's theorem, the degree of correlation between spatially separated measurements on a quantum system is limited by certain inequalities if one assumes the condition of locality. Quantum mechanics predicts that this limit can be exceeded, making it nonlocal. We analyse the effect of an environment modelled by a fluctuating magnetic field on the quantum correlations in an EPR singlet as seen in the Bell inequality. We show that in an EPR setup, the system goes from the usual ‘violation’ of Bell's inequality to a ‘non-violation’ for times larger than a characteristic time scale which is related to the parameters of the fluctuating field. We also look at these inequalities as a function of the spatial separation between the EPR pair.  相似文献   
4.
微量元素锌在治疗Bell麻痹中的作用   总被引:1,自引:0,他引:1  
为探讨急性早期应用补锌和综合疗法治疗Bell麻痹 ,将 1 5 8例Bell麻痹患者 ,随机分成两组 :(1 )补锌组 (补锌 +综合疗法 ) ;(2 )对照组 (单纯综合疗法 )。对其进行了观察对比治疗 ,同时检测了所有患者治疗前后自身对照发锌值 ,还对所有患者进行了定位诊断、面神经电反应测试、并对面肌功能进行评分。结果表明 ,对定位诊断其病变在D段、面肌功能评分在 1 1分以下、面神经无电反应患者 ,即使给予早期综合治疗 ,效果仍较差 ,而早期给予补锌加综合治疗效果优于对照组 ,其它段内患者治疗次数和治愈天数也均优于对照组。可见微量元素锌在发挥免疫应答、免疫调控中的重要作用  相似文献   
5.
We show that the minimum period modulo of the Bell exponential integers is for all primes and several larger . Our proof of this result requires the prime factorization of these periods. For some primes the factoring is aided by an algebraic formula called an Aurifeuillian factorization. We explain how the coefficients of the factors in these formulas may be computed.

  相似文献   

6.
We clarify some aspects of our derivation of a Bell-type inequality, in response to a paper by Elby.The following comments refer to Andrew Elby's discussion note immediately following our present paper.(a) We wish to stress that physical distinction between NC and LC is particularly important in the case of local realist theories violating NC for any single system but satisfying LC for any correlated many-component system. Arguments given by Elby do not rule out a reasonable theory violating NC but obeying LC. Therefore, a physically meaningful possibility exists that while Bell's inequality derived from NC is violated for a single system, the inequality derived from LC is satisfied for correlated and spatially separated (non-interacting) systems. It is precisely this possibility which was explored by HS in deriving Bell's inequality from NC.(b) Since Elby's formulation of locality condition necessarily involves a relativistic constraint at the level of individual measurements, it is pointless to discuss its compatibility with predictions derived from non-relativistic quantum mechanics, which is well known to allow superluminal communication by mechanisms such as wavepacket travel or spread. Recently this aspect has been discussed in depth by P. Ghose and D. Home,Phys. Rev. A 43, 6382 (1991). It needs to be stressed that our formulation of LC is in line with the separability condition articulated by Einstein in different contexts; see, for example,J. Franklin Inst. 221, 349 (1936), reprinted inIdeas and Opinions (Crown, New York, 1954), pp. 290–323.On leave from: Department of Physics, Bose Institute, Calcutta 700009, India.  相似文献   
7.
Clifton, Redhead, and Butterfield have recently produced a generalization of the new non-locality proof due to Greenberger, Horne, and Zeilinger. Their proof is intended to have certain advantages over the standard Belltype arguments. One of these is that, although the proof allows for causally relevant apparatus hidden variables, it avoids the need for making certain standard locality assumptions about those parameters. On closer inspection, the part of the proof which supposedly removes the need for such assumptions is shown to rest on a fallacy. This renders the proof invalid. Two other, related difficulties are explored along the way.1. CRB actually provide two nonlocality proofs, but our concern here is with the first.2. Cf. p.173 for a precise formulation of these. (Any references in these footnotes are to [1].) Note that, due to the way CRB define the µ's, these conditions are not entirely independent.3. Cf. p.174. Note that CRB claim to derive the independence of outcomes from apparatus existents via our other assumptions without imposing any other conditions on their distributions, citing Lemma 2, which we shall object to in Sec. 4 below. This should be given a careful reading; Lemma 2 only purports to derive the statistical independence of outcomes fromlocal (i.e., nearby) apparatus hidden variables. The independence of outcomes fromdistant apparatus hidden variables is assumed, rather, in OL.4. Here, and in many places, I shall rely on [1] for the details.5. CRB have endorsed this definition of M (personal correspondence).6. More precisely, those values of do so for at least one possible quadruple of apparatus existents, and measurement results; and foruncountably many setting quadruples in (p.167).7. Given CRB's way of defining the µ's so as to include the information found in the 's, the terms in OF and most of those in OL would actually be ill-defined in most cases (for each ) inany theory. This is simply because the measuring devices cannot be set to measure in two different directions at once. However, it should be possible to remedy that situation by simply redefining µ so that it includes only information about the state of the apparatus not covered by .8. CRB endorse the first of these two suggestions (personal correspondence).9. I have omitted the arguments fromA,B,C andD. Wherever they appear without arguments they will implicitly have the three with which they were first introduced. Note that M+ should ideally be indexed by and , as there is no reason to think that all the same members of M will makeABCD = +1 for different values of and .10. Cf. note 6 above.11. Note that in light of this objection to their proof, we can see that CRB also fail to establish the link they claim exists between TF, strict correlations, and the condition they call TF.TF is the four-particle analogue of the conjunction of Shimony's outcome independence and his parameter independence (p.162). They rest their claim about the link on Lemma 2 (pp.162 and 165).  相似文献   
8.
We derive none some explicit formula for the power of fractional order (differential and integral) operators.  相似文献   
9.
10.
Under investigation in this paper is a generalized (3+1)-dimensional variable-coefficient B-type Kadomtsev–Petviashvili equation, which describes the propagation of nonlinear waves in fluid dynamics. Bilinear form and Bäcklund transformation are derived by virtue of the Bell polynomials. Besides, the one- and two-soliton solutions are constructed via the Hirota method.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号