SYNTHESIS AND PROPERTIES OF ANILING ANILING AND 0-AMINOBENZENESULFONIC ACID COPOLYMER*

Poly(aniline- co-o-aminobenzenesulfonic acid) (PAOABSA) as a water soluble conducting polymerwas synthesized by chemical polymerization. The productivity and the room-temperature conductivity of thecopolymer were measured as a function of the reaction conditions, such as reaction temperature, the ratio ofoxidant to monomer and the degree of sulfonation defined as the ratio of sulfur to nitrogen atoms(S/N). Themain results obtained are summarized as follows : (1) lower reaction temperature (at about 0℃) is favorablefor the enhancement of the room-temperature conductivity of the copolymer; (2) higher content of oxidant isunfavorable for increasing the room-temperature conductivity of the copolymer; (3) both productivity androom-temperature conductivity of the copolymer decrease with increase of the degree of sulfonation whichwas always lower than 0.5 even an excess of o-aminobenzenesulfonic acid was added, probably because thereactivity ratio of aniline (γ=2.99± 0.05) is much higher than that of o-aminobenzenesulfonic acid (γ_2 = 0.06±0.02) estimated by using Fineman-Ross method and least square method.     

Electroweak tests with τ leptons at LEP

We report on two sensitive tests of lepton universality carried out by the 4 LEP experiments at the Z⁰ pole. From measurements of the τ polarization in e⁺ e^?→τ ⁺ τ ^?, the ratios of the vector and axial vector coupling constants of the electron and the tau lepton to the weak neutral current are obtained to beg _{v e} /g _{a e} =0.066±0.015 andg _{V τ} /g _{A τ} =0.070±0.009 respectively. From measurement of the τ lifetime and the τ leptonic branching ratios, the ratio of the coupling constants describing weak leptonic decays of the τ and the μ is measured to beG _τ /G _μ =0.996±0.008.     

Standard<Emphasis Type="Italic">SU</Emphasis>(5) supergravity grand unification model and predictions

A review is given of the StandardSU(5) supergravity model. This model has passed an important check regarding unification of the electro-weak and the strong couplings using high precision LEP data. It is shown that for a significant domain of the parameter space the model also satisfies constraints on the SUSY spectrum from CDF and LEP, as well as proton stability and cosmological relic density constraints.     

水稻三系及其杂种F1的核组蛋白研究

本文提取了杂交水稻COryza Sativa L.)的三系及其F,代的组蛋白，采用聚丙烯酞胺凝胶电泳及SDS-聚丙烯酞胺凝胶电泳进行分析，并与小牛胸腺组蛋白进行了比较.水稻和小牛胸腺的H,,H‘在两种凝胶电泳中都显示了相同的泳动率.水稻H:. , H:、比小牛胸腺中的相应组份在两种凝胶电泳中皆显示较低的泳动率，具较大的分子量.在我们的研究范围中，H,表现出种的特异性，而且杂种F:的H,含量高于亲本，这提供了一种从分子遗传学角度来研究杂种优势的可能性.     

基于PXI总线的阵列探测器数据获取系统

描述了一种适用于阵列探测器的数据获取系统。系统基于PXI总线, 采用标准NIM插件作为前端电子学。系统软件采用C/C++语言编写, 在线分析通过调用ROOT类库实现, 系统运行在Linux操作系统下。多次测试结果表明, 系统稳定可靠, 单个ADC通道可以处理的最大事例率为40 kHz。A data acquisition system for array detectors is described. The system is based on PXI bus with standard NIM modules used as front\|end electronics. The system software is written in C/C++ language with its online analysis modules realized by ROOT class library. Several runs of the system under Linux show that it is reliable and is capable of handling event rates up to 40 k events/s for 1 ADC channel.     

Physics with large extra dimensions

The recent understanding of string theory opens the possibility that the string scale can be as low as a few TeV. The apparent weakness of gravitational interactions can then be accounted by the existence of large internal dimensions, in the sub-millimeter region. Furthermore, our world must be confined to live on a brane transverse to these large dimensions, with which it interacts only gravitationally. In my lecture, I describe briefly this scenario which gives a new theoretical framework for solving the gauge hierarchy problem and the unification of all interactions. I also discuss a minimal embedding of the standard model, gauge coupling unification and proton stability. On leave from: Centre de Physique Théorique, Ecole Polytechnique, 91128 Palaiseau, Cedex, France.     

Simulation and design of a bandpass filter on metasubstrates

This work presents an analysis of the microstrip bandpass filter on metamaterial substrates. The filter is composed of two ring resonators with quarter-wavelength side-coupled sections. The filter input is provided, as well as the output port, using a quarter-wavelength side-coupled microstrip line section. Simulations by finite element method have been carried out to verify the effect of the metamaterial substrate properties on the filter performance, and to compare these results to those obtained considering isotropic substrate.     

Line width analysis of a tunable optical filter based on free-space optics

The line width of a tunable optical filter based on free-space optics was analyzed. The relationship between the line width and the Gaussian beam waist was theoretically derived and experimentally verified. The experimental results meet the theoretical analysis well, which is beneficial for the design of a tunable optical filter based on free-space optics.     

Mathematical modelling and numerical simulation of the morphological development of neurons

Background

The morphological development of neurons is a very complex process involving both genetic and environmental components. Mathematical modelling and numerical simulation are valuable tools in helping us unravel particular aspects of how individual neurons grow their characteristic morphologies and eventually form appropriate networks with each other.

Methods

A variety of mathematical models that consider (1) neurite initiation (2) neurite elongation (3) axon pathfinding, and (4) neurite branching and dendritic shape formation are reviewed. The different mathematical techniques employed are also described.

Results

Some comparison of modelling results with experimental data is made. A critique of different modelling techniques is given, leading to a proposal for a unified modelling environment for models of neuronal development.

Conclusion

A unified mathematical and numerical simulation framework should lead to an expansion of work on models of neuronal development, as has occurred with compartmental models of neuronal electrical activity.

     

Thermodynamic non-additivity in disordered systems with extended phase space

Non-additivity effects in coupled dynamic-stochastic systems are investigated. It is shown that there is a mapping of the replica approach to disordered systems with finite replica indexn on Tsallis non-extensive statistics, if the average thermodynamic entropy of the dynamic subsystem differs from the information entropy for the probability distribution in the stochastic subsystem. The entropic indexq is determined by the entropy difference ΔS. In the case of incomplete information, the entropic indexq=1−n is shown to be related to the degree of lost information.