Quark Transport Properties in the Region of Coexistence of Both Hadronic and QGP Phases

The physical picture of coexistence of both hadronic and QGP phases is given by Friedberg and T.D. Lee‘s nontopology soliton model. The transport properties of quark in color space and spin space in a system of two-phase coexistence are investigated from both quantum and classical theories.     

Angle-independent and multi-dimensional myocardial elastography--from theory to clinical validation

The angle-independent myocardial elastography, which shows good performance in our proposed theoretical framework using a three-dimensional, ultrasonic image formation model based on well-established, 3D finite-element, canine, left-ventricular models in both normal and left-circumflex ischemic cases, is employed as well as validated in vivo to assess the contractility of normal and pathological myocardia. Angle-independent myocardial elastography consists of: (1) iterative estimation of in-plane and out-of-plane cumulative displacements during systole using 1D cross-correlation and recorrelation techniques in a 2D search; (2) calculation of in-plane finite strains from the in-plane cumulative motion; and (3) computation of in-plane principal strains from the finite strains by eigen decomposition with a classification strategy. The in vivo raw data of healthy and pathological human left ventricles were acquired at 136 fps in a short-axis echocardiographic view. Similar to theory, the elastographic estimates in normal clinical cases showed radial wall thickening and circumferential shortening during systole through principal strain imaging, while those in a pathological case underwent opposite strains. The feasibility of angle-independent myocardial elastography with an automated contour tracking method was hereby demonstrated through imaging of the myocardial deformation, and principal strains were proven essential in the reliable characterization and differentiation of abnormal from normal myocardia, without any angular dependence.     

Two-pion interferometry for a partially coherent evolution source

We give the formulas of two-pion Hanbury-Brown-Twiss (HBT) correlation function for a partially coherent evolution pion-emitting source, using quantum probability amplitudes in a path-integral formalism. The multiple scattering of the particles in the source is taken into consideration based on Glauber scattering theory. Two-pion interferometry with effects of the multiple scattering and source collective expansion is examined for a partially coherent source of hadronic gas with a finite baryon density and evolving hydrodynamically. We do not find observable effect of either the multiple scattering or the source collective expansion on HBT chaotic parameter.     

Detection of source inhomogeneity through event-by-event two-pion Bose–Einstein correlations

We develop a method for detecting the inhomogeneity of the pion-emitting sources produced in ultra-relativistic heavy ion collisions, through event-by-event two-pion Bose–Einstein correlations. The root-mean-square of the error-inverse-weighted fluctuations between the two-pion correlation functions of single and mixed events are useful observables for the detection. By investigating the root-mean-square of the weighted fluctuations for different impact parameter regions people may hopefully determine the inhomogeneity of the particle-emitting in the coming Large Hadron Collider (LHC) heavy ion experiments.     

Multi-Pion Correlations in Two-Pion Interferometry

The influence of multi-pion correlations on two-pion interferometry analysis in multi-pion events can be expressed as the ratio of a multi pion correlation factor for the sample of like-pion pairs to a residual correlation factor for the reference sample.Although these two correlation factors can be partially cancelled our in data analyses,the difference between these two factors in the low relative momentum region is so large that the distortion on the analysed results of two-pion interferometry from multi-pion interference becomes a serious problem when the pion source has a small radius and the pion multiplicity of event is high.The distributions of multi-pion correlation factor C_n－2(q) can sensitively reflect the multi-pion correlation effects in the events The analyses of multi-pion correlation factor for two Bevalac streamer chamber data samples of 2.1AGeV Ne+Pb and 1.8AGeV Ar+Pb collisions show that the multi-pion correlation effect in the former data sample is greater that in the latter.     

Stable solutions for q(q) bound states with a regularized Breit potential

The Breit interaction contains singular terms which may lead to an instability in quark-antiquark bound state calculations. We regularize the Breit interaction by multiplying the singular terms in momentum space by the form factor μ2/(q2+μ2) such that the interaction is not singular at the origin and the intermediate-and long-range parts of the interaction remain unchanged. The singular terms in the Breit potential find their stable contributions in the calculations after being multiplied by the form factor with different powers. Such a regularized Breit potential with a linear and a relativistically corrected confining potential are applied to the study of qq bound states. The spectra for most familiar mesons are consistently obtained and agree well with the experimental data.     

20种α-氨基酸的太赫兹光谱及其分子结构的相关性

应用太赫兹时域光谱(THz-TDS)技术, 在室温下对构成蛋白质的20种基本氨基酸的多晶粉末压片样品进行了光谱测试分析. 结果表明, 所有氨基酸对THz波反应非常灵敏, 在0.2-3.0 THz的有效频谱范围内, 表现出各自特征吸收峰, 故而利用THz光谱可以有效地区别不同种类的氨基酸. 我们以新数据验证和补充了前人的研究结果, 建立了以氨基酸分子结构及其THz光谱特征为基础的分类方案, 讨论并揭示了氨基酸分子的结构差异与其THz吸收光谱之间的相关性. 认知这些相关性将有助于鉴定氨基酸分子, 促进THz光谱学的理论研究以及在生物医学领域的推广应用.     

A new car-following model with consideration of anticipation driving behavior

A new anticipation driving car-following (AD-CF) model is presented based on the effect of traffic anticipation in the real world. The model??s linear stability condition was obtained by applying the linear stability theory. Additionally, a modified Korteweg?Cde Vries (mKdV) equation was derived via nonlinear analysis to describe the propagating behavior of traffic density wave near the critical point. Good agreement between the simulation and the analytical results shows that the stability of traffic flow can be enhanced when the driver??s anticipation effects are considered.     

单螺杆发动机在不同进气压力下的实验研究

为了改善原有气动发动机的缺陷,提出了一种新型的气动发动机—单螺杆膨胀机,其具有容积效率高、结构控制简单、噪声低、寿命长等特点。为了测试单螺杆膨胀机的各项性能,建立了单螺杆膨胀机压缩空气动力系统,对膨胀机在不同进气压力下进行了实验研究.实验结果表明:随着进气压力升高膨胀机输出功率及总效率升高,而气耗率下降,即膨胀机在高进气压力下具有较好的动力性能、经济性能和较高的总效率。