Coupled ripplon-plasmon modes in a multielectron bubble

In multielectron bubbles, the electrons form an effectively two-dimensional layer at the inner surface of the bubble in helium. The modes of oscillation of the bubble surface (the ripplons) are influenced by the charge redistribution of the electrons along the surface. The dispersion relation for these charge redistribution modes (‘longitudinal plasmons’) is derived and the coupling of these modes to the ripplons is analysed. We find that the ripplon-plasmon coupling in a multielectron bubble differs markedly from that of electrons on a flat helium surface. An equation is presented relating the spherical harmonic components of the charge redistribution to those of the shape deformation of the bubble.     

Redistribution effects on line formation in moving stellar atmospheres—II. The non-isotropic redistribution functions RI,II,III(x′,n′; x,n)

The effects of photon frequency and angular redistribution arising from pure Doppler (R_I), Doppler with natural line broadening R_II and from the combined Doppler, natural and collisional line broadening (R_III) are examined for line formation in plane-parallel semi-infinite and slab differentially expanding atmospheres. Line source functions and their corresponding emergent line intensities are obtained using the full angle-dependent redistribution functions. The results are compared with those obtained assuming complete redistribution and also with those using two types of angle-averaged redistribution functions; those angle-averaged in the observer's rest frame and those angle-averaged in the fluid frame. It is found that the redistribution functions angle-averaged in the observer's rest frame can produce spurious effects on line formation in moving media, as pointed out by Magnan.¹ On the other hand, emergent line intensities obtained using the redistribution functions angle-averaged in the fluid frame are found to differ by little from those obtained using the full angle-dependent redistribution functions, for the velocity fields considered here.     

The Hanle effect with partial frequency redistribution. Construction of a frequency-dependent polarization matrix and numerical solution by a PALI method

The polarized approximate lambda iteration (PALI) technique developed for the weak field Hanle effect relies on the decomposition of the Stokes parameters I, Q and U into six cylindrically symmetrical components. It has been applied to complete and partial frequency redistribution with redistribution matrices in which frequency redistribution is decoupled from scattering polarization. For partial frequency redistribution, the decoupling is obtained by an adequate decomposition of the frequency space into several domains. By angle-averaging frequency-dependent terms in the exact weak field Hanle redistribution matrix for a normal Zeeman triplet, we construct a redistribution matrix with coupling between frequency redistribution and polarization and no domain decomposition. The coupling is contained in generalized frequency redistribution functions that depend on the magnetic field. The redistribution matrix is expanded in the Landi Degl’Innocenti spherical tensors for polarimetry and the Stokes parameters are decomposed into cylindrically symmetrical components. A PALI method is set up for the calculation of these components. The Stokes parameters are calculated for different simple atmospheric models. The positive Q direction corresponds to the linear polarization perpendicular to the solar limb. It is shown that the frequency space decomposition may induce large errors on Stokes U in the transition region between line core and line wings but can safely be used for Stokes I and Q, the errors staying less than 1% at all the frequencies.     

Non-coherent scattering in subordinate lines: III. Generalized redistribution functions

The concept of the redistribution function, which was originally introduced in order to describe a correlation between frequencies and directions of the absorbed and emitted photon in resonance scattering, has been extended to other resonance two-photon processes including resonance Raman scattering, resonance two-photon absorption and emission, and inverse Raman scattering. We have derived, within the frame of the impact approximation, the appropriate form of the generalized redistribution function. Using a suitable formalism, the generalized redistribution function takes the same form for all types of two-photon processes and contains all the redistribution functions, considered previously, as various limiting cases. In analogy to Hummer's original scheme of redistribution functions, we have derived a similar set of generalized redistribution functions, denoted as p_i(i = I, II, III, IV, V), and we have shown that the most general case is described by a linear combination of p_III and p_V, analogously to the previous results. Explicit formulae for the velocity-averaged (laboratory-frame) generalized redistribution functions p_i(i = I, II, III, IV, V) are given and possible numerical methods for their evaluation are briefly indicated.     

Microscopic Models for Chemical Thermodynamics

We introduce an infinite particle system dynamics, which includes stochastic chemical kinetics models, the classical Kac model and free space movement. We study energy redistribution between two energy types (kinetic and chemical) in different time scales, similar to energy redistribution in the living cell. One example is considered in great detail, where the model provides main formulas of chemical thermodynamics.     

Impact on the magnetic compressor due to CSR

When an electron bunch is compressed in a chicane compressor, the CSR (coherent synchrotron radiation) will induce energy redistribution along the bunch. Such energy redistribution will affect the longitudinal emittance as a direct consequence. It will also excite betatron oscillation due to the chromatic transfer functions, and hence a transverse emittance change. So, it is indispensable for us to find a way to alleviate the CSR-caused emittance dilution and the bad result of chicane compressor in PKU-FEL.     

Impact on the magnetic compressor due to CSR

When an electron bunch is compressed in a chicane compressor,the CSR (coherent synchrotron radiation) will induce energy redistribution along the bunch.Such energy redistribution will affect the longitudinal emittance as a direct consequence.It will also excite betatron oscillation due to the chromatic transfer functions,and hence a transverse emittance change.So,it is indispensable for us to find a way to alleviate the CSR-cansed emittance dilution and the bad result of chicane compressor in PKU-FEL.     

氢吸附金刚石（001）表面的第一性原理研究

采用第一性原理方法研究氢吸附的金刚石（001）表面，计算了氢吸附金刚石表面构型.通过分析吸附前后空间电荷分布的变化，发现吸附H原子的金刚石（001）表面电荷向H原子转移，即表明氢吸附的金刚石表面带负电.分析了这种现象的微观机制，以及它对金刚石表面电学性质的影响. 关键词： 第一性原理计算 金刚石（001）面 表面吸附 电荷密度分布     

一个新的用于元胞自动机模拟微观组织的溶质分配模型及其计算验证

在已有的几种溶质再分配计算模型的基础上, 建立了一个新的更为合理的溶质再分配模型.该模型充分考虑了枝晶生长过程中可能出现的固/液界面元胞的各种状态及其邻居元胞的各种状态, 根据这两者的不同状态, 分别建立不同的计算公式展开计算. 利用所建立的模型消除了原有的扩散控制的元胞自动机(CA)生长模型存在的在晶界处元胞不凝固的缺陷. 接着, 为了进一步验证模型的可靠性, 在Kurz-Giovanola-Trivedi方法控制的CA生长模型中引入新的溶质再分配计算模型, 对Al-4.7 wt%Cu 合金铸锭进行了模拟计算, 并与实验结果进行了金相组织和成分分布两方面的对比, 表明新模型具有较好的精确性. 关键词： 元胞自动机方法 微观组织模拟 溶质再分配     

基于可调负载重分配的无标度网络连锁效应分析

为了深入研究复杂网络抵制连锁故障的全局鲁棒性,针对现实网络上的负载重分配规则常常是介于全局分配与最近邻分配、均匀分配与非均匀分配的特点,围绕负荷这一影响连锁故障发生和传播最重要的物理量以及节点崩溃后的动力学过程,提出了一种可调负载重分配范围与负载重分配异质性的复杂网络连锁故障模型,并分析了该模型在无标度网络上的连锁故障条件.数值模拟获得了复杂网络抵制连锁故障的鲁棒性与模型中参数的关系.此外,基于网络负载分配规则的分析以及理论解析的推导,验证了数值模拟结论,也证明在最近邻与全局分配两种规则下都存在负载分配均匀性参数等于初始负荷强度参数即β=τ使得网络抵御连锁故障的能力最强.     

Redistribution of photogenerated carriers in neutral and charged InAs quantum dot systems

Time-integrated and time-resolved photoluminescence spectra of neutral and negatively charged self-assembled InAs quantum dots (QDs) were studied. Obtained spectra have indicated that the redistribution of carriers in QDs occurs in all samples, but the temperature dependence of spectra are quite different for neutral and charged QDs. To clarify the origin of these behaviors, a model calculation based on two possible redistribution mechanisms has been carried out, and compared with experiments to show that the carrier tunneling between neighboring QDs is suppressed in charged QDs.     

环位形下鱼骨模驱动快离子输运的数值模拟研究

考虑包含动理学效应的鱼骨模结构,使用导心轨道程序 ORBIT,在磁面坐标下研究了不同的扰动模 幅度、频率对快离子再分布的影响,并分析了粒子与扰动发生共振的条件。模拟得出,鱼骨模扰动会使快离子在 实空间、相空间中发生再分布,芯部( ψ_p/ψ _w≤0.2 ,ψ_p 为极向磁通,ψ_w 为最后一个闭合磁面的磁通)快离子密 度下降约 20%,中间磁面位置上( ψ_p/ψ _w≥0.2,ψ_p/ψ _w≤ 0.6)的快离子密度增加约 7%;通过扫描频率发现,相空间中快 离子的再分布对模式频率敏感,并分析了快离子与鱼骨模扰动共振的条件。     

On the role of intramolecular vibrational energy redistribution in infrared multiphoton excitation of polyatomic molecules

A model approach conceived to account for the processes of intramolecular vibrational energy redistribution (IVR) in the course of infrared multiphoton excitation (IRMPE) of polyatomic molecules is considered.     

The importance of the privilege in resource redistribution models for appearance of inverse-power solutions

A polemics with the opinion that power laws generically appear in systems with finite resources is carried on. Examples of simple models of redistribution of resources which lead to short-tail distributions are given. It is shown that the true cause of inverse-power distributions is some kind of privilege which is hidden at a specific method of redistribution. It is explained why some multiplicative processes lead to logexponential (i.e., inverse-power) distribution functions rather than to lognormal ones. The paper stands as the next contribution confirming the hypothesis that the adequate privilege is the cause of origin of inverse-power distributions in many phenomena.     

Kinetics of the redistribution of porphyrins between the proteins of blood and membranes

A comparative investigation of the kinetics of the redistribution of porphyrins between the lipoproteins of plasma and biological membranes is made. Isolated proteins were colored by the derivatives of chlorin e₆ and Zn-phthalocyanine, and the dynamics of the redistribution of pigments from the protein-carrier onto biological membranes (unilamellar lipid vesicles) were recorded by fluorescent methods. It is found that the rate of redistribution depends on the polarity of the molecule of the pigment. The time needed to attain equilibrium distribution of porphyrin increases on decrease in the degree of polarity from several seconds for chlorin e₆ to tens of minutes for nonpolar pigments. Very slow redistribution (several hours) was observed on displacement of the trimethyl ester of chlorin e₆ and Zn-phthalocyanine from low-density lipoproteins. It is shown that this effect can be attributed to the specific features of the localization of the centers of binding extremely nonpolar porphyrins in the composition of low-density lipoproteins. Reported at the VIIIth International Conference on Spectroscopy of Porphyrins and Their Analogs, Minsk, September 22–26, 1998. Belarusian State University, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 541–545, July–August, 1999.     

Statistical equilibrium in simple exchange games II. The redistribution game

We propose a simple stochastic exchange game mimicking taxation and redistribution. There are g agents and n coins; taxation is modeled by randomly extracting some coins; then, these coins are redistributed to agents following Polya's scheme. The individual wealth equilibrium distribution for the resulting Markov chain is the multivariate symmetric Polya distribution. In the continuum limit, the wealth distribution converges to a Gamma distribution, whose form factor is just the initial redistribution weight. The relationship between this taxation-and-redistribution scheme and other simple conservative stochastic exchange games (such as the BDY game) is discussed.     

Soliton Solutions in Three-Component Bose-Einstein Condensates

We obtain soliton and plane wave solutions for the coupled nonlinear Schrotinger equations, which describe the dynamics of the three-component Bose-Einstein condensates by using the Hirota method. Meanwhile we find that the system which has attractive atomic interaction will only possess a shape changing （inelastic） collision property due to intensity redistribution in the absence of the spin-exchange interaction. As a discussed example, we investigate the one-soliton, two-soliton solutions and collisional effects between bright two-soliotn solution, which lead to the intensity redistribu tion.     

Deuterium and hydrogen distribution in a stack of Ta|(CD2) n |Ta foils under the action of high-temperature pulsed nitrogen plasma

Using the method of the elastic recoil detection (ERD) of hydrogen nuclei and a Plasma Focus setup (PF-4), we study the processes of the storage and redistribution of hydrogen and deuterium atoms in a stack of two tantalum foils and a deuterated polyethylene film sandwiched between them under pulsed irradiation with hot nitrogen plasma. It is established that the redistribution of implanted deuterium and hydrogen occurs at greater depths in both tantalum foils after 30 pulses of nitrogen plasma. The maximum concentrations of hydrogen and deuterium, namely 7 and 45 at % are observed on the surface of the second tantalum foil which is more distant from the PF-4 setup. The redistribution of deuterium from deuterated polyethylene onto the surface and volume of both Ta foils is observed. The observed phenomenon can be explained by the breaking of chemical bonds in the deuterated polyethylene and the transfer of freed deuterium into the Ta foils under the action of strong shock waves formed in the structure, as well as the accelerated diffusion of hydrogen and deuterium in the stress field caused by the shock wave.     

Three-dimensional tomography of the beryllium fermi surface: surface charge redistribution

The discontinuity in the lattice periodic potential at surfaces often leads to the creation of new electronic surface states. We developed a photoemission based Fermi surface tomography whose surface sensitivity allowed us to quantify the charge redistribution on the Be(0001) surface. The volume enclosed by the bulklike Fermi surface is significantly reduced at the surface, consistent with the charge transfer to the two surface states as estimated from the area within their two-dimensional Fermi contours. This result represents the first quantification of the charge redistribution on a natural surface termination.     

HNO二聚体蓝移氢键的理论研究

利用分子轨道从头算理论和密度泛函理论结合不同理论基组对于N-H…O蓝移氢键进行了详细的研究.利用标准方法和均衡校正方法对二聚体进行了几何优化,振动频率和相互作用能的计算.拓扑学和自然键轨道理论对于蓝移氢键的本质进行分析.自然键轨道(NBO)分析表明,σ*(N-H)轨道上电子密度降低是电子密度重排效应的结果.分子内电子重排、轨道再杂化和电子受体内部结构重组共同作用结果导致了N-H的振动频率大幅蓝移现象的出现.