冲击磁铁回路电感对传输线放电的影响

分析了脉冲调制器产生短脉冲时冲击磁铁回路电感对脉冲前后沿和宽度不可忽略的影响，从理论上导出了冲击磁铁回路电感与脉冲前后沿的关系，给出并分析了几组实验结果，提出了采用屏蔽结构和适当增加阻抗等两种可行的减小脉冲前沿的方案。     

Darkon dark matter, unparticle effects and collider physics

In this talk I report recent results on the simplest dark matter model, the Darkon model, and supersymmetric unparticle effects on dark matter, and some implications for coUider physics. I first discuss dark matter properties and collider signatures in the Darkon model, and then I discuss some implications for dark matter if a scalar unparticle is introduced to the MSSM.     

Der Einfluß der chemischen Bindung und der Beimischung von Wasserstoff auf die myonischen Röntgenkaskaden in Jod und Niob

Muonic X-ray spectra have been measured for NH₄I and Nb(H) (Nb with presedin H₂). The results are compared with earlier experimental data on I and Nb, and with cascade calculations using various initial populations. While only minor differences between the I lines of NH₄I and elementary I were observed, big differences between the crossover lines of Nb(H) and Nb were found. In the cases of NH₄I, I, and Nb the experimental results could well be reproduced by the cascade computations. Theμ distribution between N and I in the case of NH₄I was found to be 0.57±0.08, in agreement with a recent calculation.     

Darkon dark matter,unparticle effects and collider physics

In this talk I report recent results on the simplest dark matter model, the Darkon model, and supersymmetric unparticle effects on dark matter, and some implications for collider physics. I first discuss dark matter properties and collider signatures in the Darkon model, and then I discuss some implications for dark matter if a scalar unparticle is introduced to the MSSM.     

Spin glass theory: Numerical and experimental results in three-dimensional systems

Here I will review the theoretical results that have been obtained for spin glasses. I will concentrate my attention on the predictions of the mean field approach in three dimensional systems and on its numerical and experimental verifications.     

Centrality of the collision and random matrix theory

I discuss the results from a study of the central 12CC collisions at 4.2 A GeV/c.The data have been analyzed using a new method based on the Random Matrix Theory.The simulation data coming from the Ultra Relativistic Quantum Molecular Dynamics code were used in the analyses.I found that the behavior of the nearest neighbor spacing distribution for the protons,neutrons and neutral pions depends critically on the multiplicity of secondary particles for simulated data.I conclude that the obtained results offer the possibility of fixing the centrality using the critical values of the multiplicity.     

Information and two-level systems

I consider the general functions depending on the quantum state represented by a two-level density matrix. Quantities of relevance are state distance and informations measures, i.e. entropies. I introduce a new complex representation of such functions. Utilizing the geometric interpretation of complex mappings, I summarize several properties of such transformations of the state. In particular these results are used to suggest several possible applications to physical questions. These are tentative only, but they indicate the physical relevance of the mathematical results presented.     

Perturbation series at large orders in quantum mechanics and field theories: Application to the problem of resummation

In this review I present a method to estimate the large order behavior of perturbation theory in quantum mechanics and field theory. The basic idea, due to Lipatov, is to relate the large order behavior to (in general complex) instanton contributions to the path integral representation of Green's functions. I explain the method first in the case of a simple integral and of the anharmonic oscillator and recover the results of Bender and Wu. I apply it then to the φ⁴ field theory. I study general potentials and boson field theories. I show, following Parisi, how the method can be generalized to theories with fermions. Finally I outline the implications of these results for the summability of the series. In particular I explain a method to sum divergent series based on a Borel transformation. In a last section I compare the larger order behavior predictions to actual series calculation. I present also some numerical examples of series summation.     

CF_3I分子在外电场中的物理和光谱性质研究

CF_3I是公认的用以代替SF6的新型环保绝缘气体,其在外电场中的具体性质的研究至关重要.利用密度泛函理论(DFT),在B3LYP/DGDZVP基组水平上,从分子结构角度研究了CF_3I气体在外电场(-0. 02 a. u.～0. 02 a. u.)作用下的光谱特征和解离特性.计算结果表明,沿C至I方向的电场增强时:C-I键键长单调增大,能隙E_g单调减小;分子总能量先增大后减小,偶极矩先减小后增大;费米能级EF单调减小,但当电场增至C至I方向0. 010 a. u.时,费米能级EF出现局部极大值.外电场对分子红外光谱的影响表现为:沿C至I方向电场强度增大时,四个振动频率红移(包括最高峰),其余两个蓝移.分子的解离特性表现为:沿C至I方向强度超过0. 025 a. u.的电场可使C-I键断裂.以上结果为CF_3I或其与其混合物在外电场下的特性研究提供了参考.     

一种色彩向量的降维表示方法

提出了一种依据人眼的颜色视觉机制对真彩色显微生物图像进行分割的色彩向量的降维表示方法。该方法将由红绿蓝三色彩刺激经Karhunen Lo埁ｖｅ变换得到的Ｉ1I2 I3 色彩空间中的I1强度信息摒弃 ,将色彩特征由三维I1I2 I3 色彩空间向量降维为二维I2 I3 色彩向量。并以此I2 I3 色彩向量作为图像的色彩表示特征 ,运用反向传播网络对真彩色显微生物图像进行了分割实验。实验表明该方法应用于分割真彩色显微生物图像时 ,与采用I1I2色彩向量的降维方法相比 ,可优化色彩表示特征 ,加快网络的收敛速度 ,提高图像分割的正确率     

Strangeness and onset of deconfinement

I will review the current status of global strangeness production in relativistic heavy-ion collisions with particular emphasis on recent results from core-corona model. I will discuss its relevance for the detection of the onset of deconfinement.     

Meson-Meson Scattering on Anisotropic Lattices

Using the tadpole improved Wilson quark action on small, coarse, and anisotropic lattices, meson-meson scattering lengths are calculated within quenched approximation. The study covers pion-pion scattering in the I=2 channel and kaon-pion scattering in the I=3/2 channel. The results are extrapolated towards the chiral limit. Finite volume and finite lattice spacing errors are also analyzed and results in the infinite volume and continuum limit are obtained. Our results are compared with the results obtained using Roy equations, chiral perturbation theory, dispersion relations, and the experimental data. We also compare our results with other lattice results on the scattering lengths.     

A vibrational analysis of trichloroiodomethane

The infrared and Raman spectra of CCl₃I have been recorded. Band assignments have been made on the basis of the infrared results, and the Raman spectrum has been interpreted in terms of the fundamentals of CCl₃I, with additional bands being assigned to decomposition products of CCl₃I. A Urey-Bradley force constant calculation has been made, transferring results from the earlier work of Ngai and Mann.     

Origin of tweed in Au–Cu–Al alloys

The premartensitic tweed in Au–Cu–Al alloys, contrary to previous thought that resort to defects, is confirmed to be associated with the coherent embryos of an intermediate phase (I phase) embedded in parent phase. The parent?→?I phase transformation temperature was measured by differential scanning calorimeter and dynamic mechanical analysers, which shifts from 82.3 to 557.6?°C depending on the alloy composition. X-ray diffraction and transmission electron microscopes (TEM) results show that the parent?→?I phase transformation is a charge density wave transition that cannot be suppressed even by melt-spun method, which shows obvious compositional inhomogeneity between I phase and parent. The results imply that the parent?→?I phase transition is a fast displacive transformation coupled with diffusion. Moreover, accompanying the parent?→?I phase transformation, alloys demonstrate diversified microstructure revealed by TEM observation, from tweed to chessboard nanowires or twins. These findings provide the experimental evidence for that parent?→?I phase transformation in Au–Cu–Al alloys is originated from pseudospinodal decomposition as theoretically predicted.     

Estimation of copper activation parameters upon a transition from the exponential to power stress dependence of the creep rate

The results of estimation of activation parameters in the region of exponential (I) and power (II) dependences of the steady-state creep rate of polycrystalline copper on stress were represented. It is shown that the elastic long-range stress produced by dislocations in region I can be determined directly from the dependence of the creep rate on the stress. An energy criterion of the transition from creep region I to region II is proposed.     

Mixed mode I/II brittle fracture in V-notched Brazilian disk specimens under negative mode I conditions

The well-known round-tip V-notched Brazilian disk specimen is utilized for conducting mixed mode I/II fracture tests on PMMA under negative mode I conditions for different notch angles and various notch radii with the aim to measure experimentally the fracture load and the fracture initiation angle. It is shown by the finite element analysis that although the notch is under negative mode I loading, one side of the notch border still experiences tensile tangential stresses suggesting that fracture would take place from the same side of notch border. Experimental observations also indicated that fracture occurs from the tensile side of the notch border confirming the finite element results. The experimental results are then theoretically estimated by means of two stress-based brittle fracture criteria, namely the round-tip V-notch maximum tangential stress and the mean-stress criteria. It is shown that both criteria provide very good predictions to the experimental results obtained under negative mode I conditions.     

Line bundle twisted chiral de Rham complex,chiral Riemann-Roch formula and D-branes on toric manifolds

I present the results of the elliptic genus calculations in various examples of twisted chiral de Rham complex on one- and two-dimensional toric compact manifolds. The explicit calculations are made for line bundle twisted chiral de Rham complex on ?¹, ?² and Hirzebruch surface. Based on these results I propose the elliptic genus expression of the bundle twisted chiral de Rham complex for general smooth compact two dimensional toric manifold. The expression resembles Riemann-Roch formula and coincides with the later in certain limit. I interpret the result in terms of infinite tower of open string oscillator contributions and identify directly the open string boundary conditions of the corresponding bound state of D-branes.     

Observed effects of a changing step-edge density on thin-film growth dynamics

We grew SrTiO(3) on SrTiO(3)(001) by pulsed laser deposition, while observing x-ray diffraction at the (00(1/2)) position. The drop DeltaI in the x-ray intensity following a laser pulse contains information about plume-surface interactions. Kinematic theory predicts DeltaI/I = -4sigma(1 - sigma), so that DeltaI /I depends only on the amount of deposited material sigma. In contrast, we observed experimentally that |DeltaI /I| < 4sigma(1 - sigma) and that DeltaI /I depends on the phase of x-ray growth oscillations. The combined results suggest a fast smoothing mechanism that depends on surface step-edge density.     

用总能量密度泛函集团方法研究I/Si(111)及I/Ge(111)表面吸附

本文中用自洽总能量密度泛函集团方法研究了Ⅶ族的Ⅰ在Si(111)和Ge(111)表面的吸附。分别采用了两种集团模型来模拟顶位和三度位构型,用总能量极小原理确定了吸附的最佳构型和吸附能量,得到顶位比三度位吸附更为稳定的结果,与SEXAFS实验结果一致。本文还计算了Ⅶ族元素F,Cl,Br,I在Si(111)顶位吸附的状态密度,讨论了这系列DOS的变化情况,并与实验或其他理论结果进行了比较,最后还讨论了半经验EHT方法的适用性及限制。 关键词：     

Theory of the resonance escape factors of plasma resonance lines basing on the exact Voigt profile

In this paper, based on the exact Voigt profile we obtained, we derive the theory of resonance escape factors of plasma resonance lines, for both Lorentzian profile and Voigt profile. The oscillator strength, the number density of the absorbing atoms in the ground state, and the optical depth in the line center are discussed. As an example, the helium He I 1083.0 nm, lithium Li I 670.970 nm and carbon C I 111.74 nm are discussed for infrared, visible and ultraviolet regions. The results we calculated are in good agreement with the experimental results. These calculations will be significant in the theoretical analysis of plasma.