Quantum secure direct communication with quantum encryption based on pure entangled states

This paper presents a scheme for quantum secure direct communication with quantum encryption. The two authorized users use repeatedly a sequence of the pure entangled pairs (quantum key) shared for encrypting and decrypting the secret message carried by the travelling photons directly. For checking eavesdropping, the two parties perform the single-photon measurements on some decoy particles before each round. This scheme has the advantage that the pure entangled quantum signal source is feasible at present and any eavesdropper cannot steal the message.     

内凝固浴组成对聚醚酰亚胺中空纤维膜结构和性能的影响

以N,N-二甲基乙酰胺(DMAc)为溶剂,水为外凝固浴,乙醇为内凝固浴,DMAc为内凝固浴添加剂,采用相转化法制备了聚醚酰亚胺(PEI)中空纤维膜,研究了内凝固浴组成和纺丝液浓度对膜结构和性能的影响。实验结果表明,随着内凝固浴中DMAc含量在一定范围内增加,纤维断面指状孔有所减少,内表面由无孔到有微孔出现,但膜的水通量下降,截留率不受影响;随着纺丝液浓度提高,膜的水通量下降,截留率提高。     

EFFECT OF PROCESSING METHOD ON THE IMPACT STRENGTH OF POM/TPU/CaCO3 TERNARY COMPOSITES

Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles.     

基于三阶段DEA模型的中国省际全要素能源效率研究

基于三阶段DEA(数据包络分析)模型测算了我国2009年29个省市的全要素能源效率及其分解变量.研究结果表明:环境因素对于各地区全要素能源效率有显著影响.各地区政府财政支出与对外开放程度的提高是全要素能源效率改善的有利因素;各地区第三产业增加值占GDP的比重与各地区工业总产值占中国所有工业总产值的比重的增加是全要素能源效率提高的不利因素.另一方面在剔除环境和随机因素影响后,全国平均规模效率的降低是全要素能源效率的下降主要因素.最后由全要素能源效率的聚类分析结果发现,我国全要素能源效率的区域差异明显,东部表现最优,中部次之,西部最次.     

Multivariate aging properties of epoch times of nonhomogeneous processes

The purpose of this paper is to give conditions on the parameters of nonhomogeneous Poisson and nonhomogeneous pure birth processes, under which the corresponding random vector of the first n epoch times has some multivariate stochastic properties. These results provide an inside to understand the effect of the time over the occurrence of events in such processes. Some applications of these results are given.     

Asymmetric synthesis of α-monofluoromethyl- and α-difluoromethylbenzylamines through regioselective hydrogenolysis

Asymmetric synthesis of α-monofluoromethyl- and α-difluoromethylbenzylamines through regioselective hydrogenolysis is described. Hydrogenolysis of diastereomerically pure bis(α-methylbenzyl)amine derivatives having partially fluorinated methyl group at benzylic position also proceeded with a high regioselectivity as well as in the case of α-trifluoromethyl group. Moreover, opposite asymmetric induction was observed in reduction of chiral imines derived from partially fluorinated acetophenone and α-phenylethylamine.     

A new series of materials containing basic sulphates of iron(III)

Series of basic sulphates which were precipitated by the hydrolysis of Fe(OH)SO₄ in the presence and absence of metallic iron were studied from compositional, crystallographic and thermal decomposition points of view. The results are presented and discussed. It was found that high pure iron oxides as well as high grade red iron oxide pigments can be obtained by agitating the basic sulphates in hot ammonical medium followed by roasting. Commercial exploitation of the results is suggested.Left the laboratory to settle in domestic life.The authors are thankful to the Director, Prof. H. S. Ray for his kind permission to publish the results. One of us (SM) is also thankful to the Council of Scientific and Industrial Research, New Delhi, for the award of a Senior Fellowship.     

Wigner Function:from Ensemble Average of Density Operator to Its One Matrix Element in Entangled Pure States

We show that the Wigner function W = Tr(△ρ) (an ensemble average of the density operator ρ, △ is theWigner operator) can be expressed as a matrix element of ρ in the entangled pure states. In doing so, converting fromquantum master equations to time-evolution equation of the Wigner functions seems direct and concise. The entangledstates are defined in the enlarged Fock space with a fictitious freedom.     

Uniqueness of continuum one-dimensional Gibbs states for slowly decaying interactions

We consider one-dimensional grand-canonical continuum Gibbs states corresponding to slowly decaying, superstable, many-body interactions. Absence of phase transitions, in the sense of uniqueness of the tempered Gibbs state, is proved for interactions with anNth body hardcore for arbitrarily largeN.     

邻硝基苯基荧光酮流动注射分光光度法测定微量钛

本文研究了以邻硝基苯基荧光酮－溴化十六烷基三甲基铵为试剂的流动注射分光光度测定钛的新方法。该方法分析频率达到１００次／ｈ，线性范围为０～１．０μｇ／ｇ方法重性好，用于合金钢及纯铝中钛的测定，结果满意。