Semi-Quantum Bi-Signature Scheme Based on W States

International Journal of Theoretical Physics - A semi-quantum bi-signature scheme based on W states is designed, in which two signers sign the same message. The unconditional security of the new...     

密度依赖口袋常数下奇异物质的热力学自洽处理及其对混合星性质的影响

在MTT口袋模型的基础上采用密度依赖口袋常数,给出了奇异夸克物质的热力学关系,并用于描述奇异夸克物质及混合星内的夸克相,研究了奇异星、混合星的性质.结果表明,密度依赖口袋常数下,奇异夸克物质的压强公式中有一个附加项,而能量密度中则没有,从而保证了系统的热力学自洽性.在新的热力学关系下,奇异夸克物质的状态方程变软,相应的奇异星的引力质量和对应的半径均变小;混合星的状态方程也变软,其质量变小,而对应的半径也变小.说明经热力学自洽处理后该模型对中子星的状态方程及相应的质量-半径关系等都有显著的影响.     

Dynamic Processes of Cross-Tail Current in the Near-Earth Magnetotail

Current dynamic processes in realistic magnetotail geometry simulations under various driven conditions and Hall effects. are studied by Hall magnetohydrodynamic （MHD） Associated with the external driving force, a thin current sheet with a broad extent is built up in the near-Earth magnetotail. The time evolution for the formation of the current sheet comprises two phases： slow growth and a fast impulsive phase before the near-Earth disruption of the current sheet resulting from the fast magnetic reconnection. The simulation results indicate that as the external driving force increases, the site and the tailward speed of the near-Earth current disruption region are closer to the Earth and faster, respectively. Whether the near-Earth disruption of the current sheet takes place or not is mainly controlled by Hall effects. It is found that there is no sudden disruption of the current sheet in the near-Earth region if the ion inertial length is below di= 0.04.     

邻苯二甲酸氢铵NH4(C8H5O4)(s)的低温热容和热化学研究

选择分析纯邻苯二甲酸和浓氨水为反应物,合成了邻苯二甲酸氢铵.利用元素分析、FTIR和X-射线粉末衍射技术表征了它的组成和结构.用精密自动绝热热量计测定了它在78～400 K温区的摩尔热容,将该温区的摩尔热容实验值用最小二乘法拟合,得到摩尔热容(Cp,m)随折合温度(X)变化的多项式方程,利用此方程计算出该温区内每隔5 K的舒平热容值和相对于298.15K的各种热力学函数值.另外,依据Hess定律,通过设计合理的热化学循环,利用等温环境溶解-反应热量计分别测定所设计反应的反应物和产物在所选溶剂中的溶解焓,得到该反应的反应焓为△rHθm=(1.787±0.514)kJ·mol-1.最后,利用此反应焓和反应中其他物质的热力学数据计算出邻苯二甲酸氢铵的标准摩尔生成焓为:△fHθm[NH4(C8H5O4),s]=-(912.953±0.628)kJ·mol-1.     

飞秒激光脉宽对非绝热耦合分子波包运动的影响研究

利用含时波包法研究了强飞秒泵浦-探测激光场中激光脉宽对非绝热耦合NaI分子波包运动的影响.发现波包的振荡周期随脉宽增长而增大,而振荡幅度随脉宽增长而减小.非绝热效应引起的波包在交叉区域的分裂情况影响各态布居.脉宽增长,NaI分子的激发概率增大,而解离概率减小.研究表明调节激光场脉宽可实现对波包运动的控制从而控制态布居的选择性分布.研究结果可以为实验上实现分子的光控制以及量子调控过程提供一定的参考.     

Study on Bd → ø KS Decay in EDQS Model

We study B_d → ø K_S decay in extra down-type quarks (EDQS) model with a non-universal Z boson associated with flavor changing neutral currents (FCNCs) at the tree level. With the up-to-date experimental data of Br(B_d → ø K_S, S_øKS, and A_øKS, we derive the bounds on the Z-b-s coupling parameter |U_bs| and the new weak phase ø, using the constrained parameter spaces, we finally give predictions for B_s → øø decay, which could be tested atthe Fermilab Tevatron and the LHC-b experiments.     

A formula used to subtract the effect of gamma-ray of the others to that of measured reaction in measurement of cross section of nuclear reaction and its application

Abstract According to the regulation of growing and decay of artificial radioactive nuclide, a formula used to subtract the effect of characteristic γ-ray of the others to that of measured reaction was deduced. And then the cross sections of 120Te (n, 2n)119mTe reaction induced by neutrons around 14 MeV were measured by activation relative to the 93Nb (n, 2n)92mNb. In the process of the cross sections measured to be calculated, it was subtracted that the effect of characteristic γ-ray of 126Te (n, p)126Sb to that of measured 120Te (n, 2n)119mTe reaction using the formula deduced. The experimental results were (689±37) and (750±41) mb at the neutron energies of (13.5±0.3) and (14.6±0.3) MeV, respectively. Measurements were carried out by γ-detection using a coaxial HPGe detector. As samples, spectroscopically pure tellurium powder has been used. The fast neutrons were produced by the T(d, n)4He reaction. The neutron energies in these measurements were determined by the method of cross-section ratios between 90Zr (n, 2n) 89m+gZr and 93Nb (n, 2n) 92mNb reactions.     

A theoretical study about the chirped pulse amplification laser

Starting from the Maxwell‘s equation,and using the resonant-dipole equation together with the multilevel rate equations which take the effects of energy relaxation into consideration,we have derived a more realistic numerical model of the chirped pulse amplification for an ultra-broad band width laser amplifier.Numerical simulations of this model show that both the intensity profile and the energy fluence of the amplified chirped pulse are closely connected with the two relaxation effects:the relaxation of the thermalization among the components of the laser multiplets and the depletion of the lower laser level.The results are valuable for the design of ultra-broad bandwidth chirped pulse amplification lasers.     

1-(4-甲氧基)苯甲酰基-3-(4,6-二甲基嘧啶-2-氨基)硫脲的晶体结构、 理论计算及生物活性

2-氨基-4,6-二甲基嘧啶与硫氰酸钾、4-甲氧基苯甲酰氯在乙酸乙酯中反应, 合成了1-(4-甲氧基)苯甲酰基-3-(4,6-二甲基嘧啶-2-氨基)硫脲, 并用X射线单晶衍射法测定其晶体结构, 晶体属单斜晶系, 空间群为P21/n, 晶胞参数为: a＝1.0134(4) nm, b＝1.3172(5) nm, c＝1.0988(4) nm, β＝91.671(8)°, V＝1.4661(9) nm3, Dc＝1.433 g/cm3, μ＝0.234 mm－1, F(000)＝664, Z＝4, R1＝0.0571, wR2＝0.1328. 运用Gaussian 03程序, 对标题化合物进行了HF/6-31＋g(d)和B3LYP/6-31＋g(d)水平的几何全优化和频率计算, 并对其成键情况及自然键轨道(NBO)进行了分析. 初步实验证明该化合物具有良好的生物活性.     

Design guidelines and characteristics of beam-shaping microstructure optical fibers

Microstructure optical fibers with flat-top fundamental mode are first proposed by introducing a low-index inner core into the core of index-guiding microstructure optical fibers. The design guidelines and characteristics of beam-shaping microstructure optical fibers are demonstrated. The interrelationships of inner-core index with laser wavelength, air hole diameter and size of inner core are investigated. The influence of the relative size of inner core on the spatial profile of the fundamental mode is demonstrated. Moreover, sensitivity of the flat-top fundamental mode profile from the slight change of the optimum inner-core index value is studied. Starting from these results we deduce that it is possible to fabricate beam-shaping microstructure fibers with nowadays technique.