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51.
52.
B W Elliott  H N Eisen  L A Steiner 《Nature》1982,299(5883):559-561
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53.
54.
S Bose  PL Knight  MB Plenio  V Vedral 《Pramana》2001,56(2-3):383-391
We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity. We also show how this scheme can be modified to a teleportation with insurance.  相似文献   
55.
We give a holomorphic extension result for continuous CR functions on a non-generic CR submanifold N of ℂ n to complex transversal wedges with edges containing N. We show that given any v∈ℂ n ∖(T p N+iT p N), there exists a wedge of direction v whose edge contains a neighborhood of p in N, such that any continuous CR function defined locally near p extends holomorphically to that wedge.  相似文献   
56.
Summary Regularities in the variation of retention indices (I) and index increments (δI/°C, H, ΔI) of monosubstituted cyclopentenes and cyclohexenes with molecular structure on various liquid phases are discussed. An equation for the linear dependence of I on the carbon number is given. Differences in gas chromatographic characteristics between 1- and 3-isomers are more pronounced in the n-alkylcyclopentene series. In the n-alkylcyclohexene series extension of the side chain and increase of column temperature lead to the inversion of the elution order of 1-and 3-isomers. The temperature increments of I for cyclenes are markedly greater than those for open chain hydrocarbons (n-alkenes, n-alkynes).  相似文献   
57.
The reaction of one equivalent of Cp*2UCl2 with 2-(trimethylsilylimino)-1,3-di-tert-butylimidazoline in boiling toluene afforded a one electron oxidation of the uranium metal and the opening of the N-heterocyclic ring, resulting in the formation of an organometallic uranium(V) imine complex. This complex crystallized with one molecule of toluene in the unit cell, and its solid-state structure was determined by X-ray diffraction analysis. When the same reaction was performed in perdeuterated toluene, a myriad of organometallic complexes were obtained, however, when equimolar amounts of water were used in toluene, the same complex was obtained, and its solid state characterization shows two independent molecules in the unit cell with an additional water molecule. For comparison of the geometric parameters, the corresponding isolobal anionic uranium(IV) complex [Cp*2UCl3]? was synthesized by the reaction of Cp*2UCl2 with 1,3-di-tert-butylimidazolium chloride, and the resulting U(IV)-ate complex was characterized by X-ray diffraction analysis.  相似文献   
58.
采用密度泛函理论计算研究了在铈表面掺杂的过渡金属(TM)离子对表面晶格氧原子活化的影响.为此,测定了经TM离子修饰的CeO2最稳定(111)表面终端的结构和稳定性.除了保持八面体氧配位的锆和铂掺杂剂外, TM掺杂剂在取代表面Ce离子时更倾向于正方形平面配位.除了Pt(1.14 eV)和Zr(正方形平面配位不稳定)外,所有TM掺杂剂的表面结构从八面体到正方形平面都很容易.通常,四价TM阳离子的离子半径比Ce^4+的小得多,从而导致了显著的拉伸应变晶格,并解释了氧空位形成能量的降低.除Zr外,当产生一个氧空位时,优先形成正方形平面结构.热力学分析表明, TM掺杂CeO2表面在典型环境催化条件下存在氧缺陷.一个具有实际意义的例子是锆掺杂CeO2(111)中的晶格氧容易活化,从而有利于CO氧化.研究结果强调了晶格氧活化的本质和TM掺杂剂在TM-铈固溶催化剂中的优选位置.  相似文献   
59.
Heats of mixing (H E)ofn-octane with 1,2,3,4-isomers ofn-octyne,n-heptane withn-1-heptyne andn-nonane withn-1-nonyne at temperatures from 298.15 to 318.15 K were measured with aCalvet-type microcalorimeter. The results are presented in tables and correlated with theRedlich-Kister equation.
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60.
Solid supported or ligand capped gold nanomaterials (AuNMs) emerged as versatile and recyclable heterogeneous catalysts for a broad variety of conversions in the ongoing catalytic ′gold rush′. Existing at the border of homogeneous and heterogeneous catalysis, AuNMs offer the potential to merge high catalytic activity with significant substrate selectivity. Owing to their strong binding towards the surface atoms of AuMNs, NHCs offer tunable activation of surface atoms while maintaining selectivity and stability of the NM even under challenging conditions. This work summarizes well-defined catalytically active NHC capped AuNMs including spherical nanoparticles and atom-precise nanoclusters as well as the important NHC design choices towards activity and (stereo-)selectivity enhancements.  相似文献   
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