2 + 1 Flavors QCD Equation of State in NJL Model with Proper Time Regularization

Totally symmetric A_1g phonons are studied for the equilibrium and coherent states of a Bi₂Te₃ lattice. Equilibrium phonons were investigated in the frequency domain by the method of spontaneous Raman scattering, whereas coherent phonons were studied by the method of active femtosecond spectroscopy in the time domain. In the latter case, femtosecond laser pulses were used both for generating and detecting coherent A_1g phonons having a well-defined phase allowing the selective optical control of the lattice dynamics. A comparison of the results obtained in the frequency and time domains suggests that diagonal and nondiagonal elements of the density matrix of lattice excitations relax with the same characteristic time to the equilibrium and zero values, respectively.     

Sixth Harmonic of A Nd：YVO4 Laser Generation In KBBF for ARPES

We report that a deep ultraviolet （DUV） laser from the sixth harmonic of a 1064nm laser has been firstly used as light source in an ultrahigh energy-resolution angle-resolved photoemission spectroscopy （ARPES）. The wavelength is 177.3nm obtained by using the second harmonic KBe2BO3F2 crystal with a frequency tripled 1064nm Nd：YVO4 laser. The large flux （10^14 - 10^15 photons/s） and narrow line width （0.26 meV） are suitable for the ultrahigh-energy resolution ARPES. The laser-ARPES can be a powerful tool to study the electronic structure at and near the Fermi level of the superconductor and correlated materials. The laser-ARPES has worked more than 500 h already.     

A convenient new procedure for converting primary amides into nitriles

An operationally simple and high-yielding procedure has been developed for the conversion of primary amides to the corresponding nitriles, using ethyl dichlorophosphate/DBU as the mild dehydrating agent.     

有机金属化合物中二级化学键的理论研究(Ⅲ)──金属原子簇化合物离子[M3(CO)9CCO」2-(M=Fe,Ru,Os)结构的特异性及二级化学键

应用ICONS(EHMO)分子轨道方法,讨论了金属原子簇化合物离子[M₃(CO)₉CCO]^2－(M=Fe,Ru,Os)的结构特异性及配体(CCO)在金属原子基平面上的取向,并表明了二级化学键的存在.     

Further Understanding of Hydrogen Atom: Yangian Approach and Physical Effect

By applying the representation theory of Y(sl(2)) to Hydrogen atom (HA) the correct spectrum are re-derived. This indicates the consistence between HA and the Yangian algebraic structure and guarantees that there is democracy between angular momentum L and Yangian current J in the sense of conserved currents. The physical effect of Yangian in HA has been predicted that preserves all the known results for HA, but gives rise to abnormal intensities in the spectrum lines near the free state.     

有机化合物中二级化学键的理论研究(Ⅳ)——喹啉基氮杂大环铜配合物中的二级化学键

前文［１,２］报道了二级化学键存在于若干金属有机化合物以及某些簇合物中,实际上,在Ｆｉｇ．１ＣｒｙｓｔａｌｓｔｒｕｃｔｕｒｅｏｆＣｕＬ２［１４］┐２ｑｕ某些配合物体系中亦存在着二级化学键．本文将着重研究喹啉基氮杂环铜配合物（ＣｕＬ２［１４］－２ｑｕ）...     

Implications on the origin of cosmic rays in light of 10 TV spectral softenings

Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons(and probably also for Helium nuclei).Very recently,the DArk Matter Particle Explorer(DAMPE)measurement about the proton spectrum clearly reveals such a softening with a high significance.Here we study the implications of these new measurements,as well as the groundbased indirect measurements,on the origin of CRs.We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously.In the framework of multiple components,we discuss two possible scenarios,the multiple source population scenario and the background plus nearby source scenario.Both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies.Considering the anisotropy observations,the nearby source model is favored.     

Quasi-optimized Schwarz methods for reaction diffusion equations with time delay

In this paper, we investigate the convergence behavior of the Schwarz waveform relaxation (SWR) algorithms for solving PDEs with time delay. We choose the reaction diffusion equations with a constant time delay as the underlying model problem and try to derive optimized transmission conditions of Robin type. To this end, we propose a new method to get quasi-optimized parameter involved in the transmission conditions and it is shown that this method is essentially different from the existing ones. Moreover, when the situation is reduced into the heat equations with a constant delay, we show that this method results in a more efficient quasi-optimized parameter. Numerical results are provided to validate our theoretical results.     

高温高压下钠长石的阻抗谱实验研究

 在压力为1.0、2.0 GPa和温度为673～973 K条件下,采用交流阻抗谱法在YJ-3000t紧装式六面顶高压设备上原位测量了钠长石的电导率。实验结果表明：在实验的温度和压力范围内,钠长石的电导率在10^-3.0～10^-5.5 S/m变化;钠长石复阻抗的模和相角对频率有很强的依赖性;随着温度T升高,钠长石的电阻率迅速减小,电导率σ增大,并且lg σ与T^-1之间符合Arrhenius关系;在实验压力范围内,随着压力升高,钠长石的电导率降低。采用离子导电机制,对高温高压下钠长石的导电行为进行了合理解释。     

Spacer layer thickness fluctuation scattering in a modulation-doped Al_xGa_1-xAs/GaAs/Al_xGa_1-xAs quantum well

We theoretically study the influence of spacer layer thickness fluctuation(SLTF) on the mobility of a twodimensional electron gas(2DEG) in the modulation-doped Al x Ga 1 x As/GaAs/Al x Ga 1 x As quantum well.The dependence of the mobility limited by SLTF scattering on spacer layer thickness and donor density are obtained.The results show that SLTF scattering is an important scattering mechanism for the quantum well structure with a thick well layer.