Radionuclides in deposition in the Ignalina NPP region in 2005

Results of radionuclide activity concentration measurements in deposition and ground-level air conducted at the station of the Institute of Physics situated 3.5 km from the Ignalina Nuclear Power Plant (Ignalina NPP) in 2005 are analyzed. Atmospheric depositional fluxes of ⁷Be, ⁶⁰Co and ¹³⁷Cs are estimated. Radionuclide particle deposition rates are calculated. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model of the global dispersion and deposition is used to explain variations in the ¹³⁷Cs activity concentration in the ground-level air in the Ignalina NPP region in 2005. An increase in the ¹³⁷Cs activity concentration of up to 17.4 μBq m⁻³ on 30 October-5 November is studied. Modelling results show that the Chernobyl NPP Unit 4 Sarcophagus and the radiocaesium resuspension from the Chernobyl NPP accident polluted regions are sources of ¹³⁷Cs to the environment of the Ignalina NPP. Results on solubility in water of aerosols — carriers of ¹³⁷Cs — are discussed.     

Scale-free phenomenon in industries in China

In this paper, we investigate the data of industries in China and find that the frequency distributions of fixed assets and fixed-assets’ investment of industries obey power laws. We show that these power-law modes can be explained by the rules of the Simon Model, rather than the existing investment theories such as the classical investment theory or acceleration principle. Moreover, the mechanism of the investment distribution may be similar to the forest-fire model of self-organizing criticality. By introducing the complex system methods, this research changes the traditional opinion of the investment and gains some meaningful understanding in the dynamics of industries and the economic cycle.     

Absorption in the final state in reactions and decays in the medium

The role of strong absorption of particles in intermediate and final states has been considered. The range of applicability of phenomenological models of absorption has been studied. This model is nonuniversal. Its applicability depends on the type of interaction Hamiltonian and matrix element used. We also demonstrate that the violation of the unitarity condition can produce a qualitative error in the results. The absorption (decay) in the final state does not tend to suppress the total process probability as well as the probability of the channel corresponding to absorption. This is true for the reactions, decays and nˉ conversion in the medium.     

室内声学中散射研究进展

近20年,界面散射研究在声场预测、定量测量和产品研发等方面取得了重要进展,加深了我 们对散射及其作用的认识。人们可以定量地评估、设计和优化散射产品,用更加丰富的手法进行室内 音质设计。     

集成电路微互连结构中的热迁移

高工作电流在集成电路微互连结构中产生大量焦耳热,引起局部区域的温升、形成高温度梯度,金属原子沿着温度梯度反向运动发生热迁移.热迁移是集成电路微互连失效的主要原因之一.阐述了热迁移原理、失效模式及原子迁移方程.综述和分析了在单纯温度场、电场和温度场耦合等不同载荷条件下金属引线和合金焊料的热迁移研究.归纳并提出了集成电路微互连结构热迁移研究亟待解决的问题. 关键词： 集成电路 微互连 热迁移     

On phase-coherence in rescattering in multiphoton ionization and in higher-order harmonic generation

Summary  The recently discovered plateau and rings in high-order multiphoton ionization apparently have their origin in rescattering. Similarly, rescattering is involved in higher-order harmonic generation. Using a simple one-dimensional model, it is shown that the phase-coherence in this rescattering process is of considerable importance. The authors of this paper have agreed to not receive the proofs for correction. This work has been supported by the East-West Program of the Austrian Academy of Sciences and by the Austrian Ministry of Science and Transportation under project no. 45.372/2-IV/6/97. One of us (JZK) acknowledges the support of the Polish Committee of Scientific Research (grant KBN 2 P03B 007 13).     

国内CIDEP研究进展

化学诱导动态电子极化（CIDEP）是检测瞬态顺磁粒子并表征其特征的强有力的手段,对于研究光化学和光物理瞬态过程的微观机理和规律有重要意义. 本文较为详细地总结了4种常见的CIDEP机理,讨论了各种极化谱及相应的极化条件;简要介绍了国内研究小组在CIDEP理论以及在均相溶液和微复相体系中光化学过程的CIDEP研究成果.      

Persistence in random walk in composite media

We consider a class of inhomogeneous media known as composite media that is often encountered in experimental sciences, and investigate the persistence probability of a random walker in such a system. Analytical and numerical results for the crossover time scales are obtained for a composite system with two homogeneous components and three homogeneous components respectively.     

Intermolecular interactions in acetonitrile in a liquid and in a low-temperature argon matrix

IR spectra of acetonitrile embedded in an argon matrix and in a liquid are recorded. IR spectra of specimens obtained with different concentrations of acetonitrile in argon are analyzed. The spectral region of C≡N vibrations of 2200–2300 cm⁻¹ with bands of monomers and possible associates is investigated. Overlap with the band of a hot transition on the low-frequency side is responsible for the pronounced asymmetry of the band ν(C≡N). To whom correspondence should be addressed. St. Petersburg State Institute of Precision Mechanics and Optics (Technical University), 14, Sablinskaya Str., St. Petersburg, 197101, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 627–631, September–October, 1999.     

Frequency-doubling in self-induced waveguides in lithium niobate

Efficient frequency-doubling is experimentally demonstrated in presence of beam self-trapping in congruent lithium niobate crystal. The self-trapping is induced by the generated second harmonic beam via photorefractive effect under an external applied field. The local space charge field distribution, formed by the second harmonic beam, is shown to efficiently trap both wavelengths. The dynamics of self-focusing is studied along with the power evolution of the second harmonic beam. Fast tuning of phase matching conditions in the written waveguide is realized by an externally applied voltage also used for the photorefractive confinement.     

Parametric resonance in neutrino oscillations in matter

Neutrino oscillations in matter can exhibit a specific resonance enhancement — parametric resonance, which is different from the MSW resonance. Oscillations of atmospheric and solar neutrinos inside the earth can undergo parametric enhancement when neutrino trajectories cross the core of the earth. In this paper we review the parametric resonance of neutrino oscillations in matter. In particular, physical interpretation of the effect and the prospects of its experimental observation in oscillations of solar and atmospheric neutrinos in the earth are discussed. On leave from National Research Centre, Kurchatov Institute, Moscow 123182, Russia     

Synergism in electron gas in crossed fields

An electron gas in crossed electric and magnetic fields of arbitrary strength is considered in the framework of nonequilibrium statistical mechanics. It is known that more than one independent frequency existing in a system, which are of comparable magnitude, can generate coherent synergic radiation. In the present system three independent frequencies exist: viz the synchrotron frequency due to the magnetic field, the hopping frequency due to the electric field, and the plasma frequency. It is shown that all these can combine to generate a new synergic coherent radiation. The results also show the possibility of interpreting the quantum nature of Hall conductance as due to density function alone. Besides these, the solution admits the Schubnikov-de Haas oscillation of the electrical conductivity due to change in the fields.     

原位动态电子显微学研究进展

随着电镜内原位技术的不断成熟和发展,透射电子显微镜不再仅仅是材料结构表征的工具,还是实现高精度纳米加工、性能测试等的重要手段。这不但丰富了纳米尺度下开展实验研究的方法,也拓宽了透射电子显微镜的应用范围,为纳米科学与技术的迅速发展提供了新的契机。本文侧重作者所在研究小组的研究工作,以"将纳米实验室建在透射电子显微镜里"的构想为主线,从材料的原位生长、结构加工、性能表征和器件构建等四个方面综述了近年来基于透射电子显微镜的代表性原位实验研究进展。     

沿海和内陆地区多波长光谱气溶胶标高的比较分析

大气气溶胶的光学特性是大气环境、大气辐射、激光大气传输和进行空中目标识别的重要影响因子之一,而光谱气溶胶标高(spectral aerosol scale height, 简称SASH)是反映气溶胶高度分布特征的关键参量;在考虑无云状态下可见和红外波长范围的太阳辐射情况时,不仅仅要考虑总的气溶胶消光的组成,而且还要估计不同空间间隔范围内的有效高度。文章基于大气气溶胶浓度随高度指数衰减的原理,利用前向散射能见度仪和连续光谱的太阳辐射计,并辅以必要的温湿探测设备,同时测量了典型地区大气柱光学特性以及近地面层的大气水平光谱消光系数,建立多波长SASH的计算方法,获得了可见光波段(波长400,440,532,550和690 nm)的大气SASH的变化特征：无论是沿海还是内陆地区,随着波长值的增加,SASH减小;对于东南沿海某地,一般地,冬季SASH要大于夏季的SASH;而对于内陆合肥地区,冬季SASH要小于夏季的SASH。     

The in vitro Test for Pyrogens in Radiopharmaceuticals

The procedure and results of determination of pyrogenic substances in radiopharmaceutical preparations by in vitro method based on the reaction between bacterial endotoxine and Limulus a Amebocyte Lysate (LAL) have been presented in the paper. The advantage of this method as compared to the test in experimental animals performed so far has also been analyzed and proved by the fact that it enables avoidance of introduction of radioactivity in experimental animals and radiation effect on the results obtained for efficiency of investigated preparations. The in vitro method is also quick to perform and requires only small quantities of used radiopharmaceutical preparation.     

Advances in electron emission channeling measurements in semiconductors

This paper reports on recent advances in the application of electron emission channeling to studies of the lattice location of radioactive probe atoms in semiconductors. The introduction of position-sensitive electron detection has resulted in an improvement in the experimental efficiency of this method by two orders of magnitude. Electron emission channeling now is able to carry out detailed lattice location studies, and is especially interesting for cases where conventional ion beam lattice location techniques cannot be applied due to a lack of sensitivity. Characteristic features of electron emission channeling with position-sensitive detection are discussed and illustrated by results on the lattice location of Er in Si and GaAs, and on the lattice sites and stability of implanted transition metals in Si. This revised version was published online in July 2006 with corrections to the Cover Date.     

Noise in porous silicon structures in air and in conditions of gas adsorption

Low-frequency noise, in the range 1–500 Hz, is measured at room temperature in samples of Au/PS/SCS/Al structure with a layer of porous silicon. Numerical values of the Hooge parameter α_H are estimated and the dependence of α_H on the composition of the gaseous environment, where the sample is placed, is determined. Possible reasons of observed high values of α_H for the samples in air and of the increase in α_H in conditions of gas adsorption are discussed. Introducing of carbon oxide in air changes the shape of spectrum.     

Universal scaling in BCS superconductivity in three dimensions in non-s waves

The solutions of a renormalized BCS equation are studied in three space dimensions in s, p and d waves for finite-range separable potentials in the weak to medium coupling region. In the weak-coupling limit, the present BCS model yields a small coherence length and a large critical temperature, , appropriate for some high- materials. The BCS gap, , and specific heat as a function of zero-temperature condensation energy are found to exhibit potential-independent universal scalings. The entropy, specific heat, spin susceptibility and penetration depth as a function of temperature exhibit universal scaling below in p and d waves. Received: 18 July 1997 / Revised: 8 September 1997 / Accepted: 29 September 1997