Thermal and Electrical Conductivities of a Three-Dimensional Ideal Anyon Gas with Fractional Exclusion Statistics

The thermal and electrical transport properties of an ideal anyon gas within fractional exclusion statistics are studied. By solving the Boltzmann equation with the relaxation-time approximation, the analytical expressions for the thermal and electrical conductivities of a three-dimensional ideal anyon gas are given. The low-temperature expressions for the two conductivities are obtained by using the Sommerfeld expansion. It is found that the Wiedemann-Franz law should be modified by the higher-order temperature terms, which depend on the statistical parameter g for a charged anyon gas. Neglecting the higher-order terms of temperature, the Wiedemann-Franz law is respected, which gives the Lorenz number. The Lorenz number is a function of the statistical parameter g.     

宽光谱太阳能电池

太阳能电池的光谱响应特性和光电转换效率与光伏材料的微观能带结构及其宏观组装方式密切相关。无论使用哪种光伏材料,普通单结或单层太阳能电池都只能对部分波段的太阳光进行有效利用。宽光谱研究的目标是要使太阳能电池更好地利用太阳光谱所覆盖的全部波段范围的能量,从而提高太阳能电池光电转换效率。本文从化学角度综述了实现宽光谱太阳能电池的基本方法和当前的研究进展,其中包括叠层太阳能电池、中间带太阳能电池、量子点太阳能电池、热光伏太阳能电池、上转换和下转换、分子基柔性太阳能电池等方法。     

氮合金化堆焊合金往复式摩擦磨损行为的研究

在马氏体不锈钢中引入氮，通过铌、钛固氮制备氮合金化堆焊合金. 利用往复式摩擦磨损试验机测试加氮和未加氮两种堆焊合金在不同载荷(5、10和15 N)下的摩擦磨损性能，研究了其摩擦磨损行为. 结果表明:在摩擦磨损过程中，堆焊合金表面承受周期性载荷，摩擦表面出现明显的切削痕和塑性变形，其磨损机制以磨粒磨损和表面疲劳磨损为主. 氮合金化堆焊合金中，碳氮化物沿马氏体基体、晶界弥散析出，起到了明显的细晶强化和弥散强化作用，增强了基体的塑性变形抗力以及抵御磨粒磨损的能力，使磨损表面切削痕数量更少、深度更浅，抗疲劳剥落现象得到明显改善.      

Fluorimetric Method Based on Diazotization-Coupling Reaction for Determination of Clenbuterol

A novel fluorimetric method based on diazotization-coupling reaction (DCR) for the determination of clenbuterol is described. In acidic solution, clenbuterol was first diazotized with sodium nitrite, followed by coupling with bisphenol A to produce an azo-compound in NH₃- NH₄Cl buffer. It has found the diazotized clenbuterol- bisphenol A- NH₃- NH₄Cl (DCBN) system has strong fluorescence efficiency compare with the bisphenol A solution. There is a linear relationship between the increased intensity of the fluorescence emission spectra (λ_ex/λ_em?=?276 nm/306 nm) and the concentration of clenbuterol. The effects of the amount of sodium nitrite, diazo reaction time, the amount of bisphenol A, coupling reaction time and coupling reaction temperature have been examined. Under the optional conditions, clenbuterol can be determined over the concentration range of 0.02 to 2.0 μg mL^?1 with a correlation coefficient of 0.9953. The detection limit is 0.01 μg mL^?1 at a signal-to-noise ratio of 3. The relative standard deviation (RSD) for 11 repetitive determinations of 0.9 μg mL^?1 clenbuterol is 0.22 %. The utility of this method was demonstrated by determining clenbuterol in meat samples.     

非概率可靠指标和可靠度定义的比较研究

首先对几种主要的非概率可靠指标、可靠度进行了整理介绍;然后针对区间和椭球两个基本模型,对非概率可靠指标和可靠度的定义、几何意义以及计算公式进行了系统的比较分析。结果表明:线性情况下,区间可靠指标对结构功能函数具有不唯一性,椭球可靠指标与结构功能函数一一对应。因此,基于均值和离差之比定义的非概率可靠指标不适用于区间模型用来衡量结构的可靠程度。本文还将区间可靠指标与可靠度、椭球可靠指标与可靠度进行了比较,并将非概率可靠度与服从均匀分布、正态分布的概率可靠度以及服从三角形分布的非精确概率可靠度进行了比较,结果表明:区间模型相对于其他模型较为保守,椭球可靠度与概率可靠度和三角形分布下的非精确概率可靠度相接近。     

金属粒子阵列共振的偏振特性

当金属纳米粒子形成规则分布且阵列周期与单粒子的共振波长近似匹配时, 会形成一种特殊的阵列共振, 这种共振比单粒子的局域表面等离子体共振具有更窄的共振线宽和更高的共振强度. 基于修正的长波近似方法, 讨论了矩形阵列的消光截面与阵列因子和单粒子的极化率之间的关系; 并详细研究了在不同偏振的入射光照射下, 阵列因子随着电偶极子方向的改变而产生的变化, 以及这一效应对阵列共振和消光截面所产生的影响. 结果表明, 大型的方阵是偏振无关的; 在矩形阵列中, 沿着阵列两个轴向的相邻粒子之间的耦合形成了阵列因子的两个极值, 并且分别对应了散射截面的最小值.     

Interface property of silicon nitride films grown by inductively coupled plasma chemical vapor deposition and plasma enhanced chemical vapor deposition on In0.82Al0.18As

Au/silicon nitride/In_0.82Al_0.18As metal insulating semiconductor (MIS) capacitors were fabricated and then investigated by capacitance voltage (C–V) test at variable frequencies and temperatures. Two different technologies silicon nitride (SiN_x) films deposited by inductively coupled plasma chemical vapor deposition (“ICPCVD”) and plasma enhanced chemical vapor deposition (“PECVD”) were applied to the MIS capacitors. Fixed charges (N_f), fast (D_it) and slow (N_si) interface states were calculated and analyzed for the different films deposition MIS capacitors. The D_it was calculated to be 4.16 × 10¹³ cm⁻² eV⁻¹ for “ICPCVD” SiN_x MIS capacitors, which was almost the same to that of “PECVD” SiN_x MIS capacitors. The D_it value is obviously higher for the extended wavelength In_xGa_1−xAs (x > 0.53) epitaxial material as a result of lattice mismatch with substrate. Compared to the results of “PECVD” SiN_x MIS capacitors, the N_si was significantly lower and the N_f was slightly lower for “ICPCVD” SiN_x MIS capacitors. X-ray photoelectron spectroscopy (XPS) analysis shows good quality of the “ICPCVD” grown SiN_x. The low temperature deposited SiN_x films grown by “ICPCVD” show better effect on decreasing the dark current of In_xGa_1−xAs photodiodes.     

A sliding mode control for linear fractional systems with input and state delays

In this paper, a sliding mode control design for fractional order systems with input and state time-delay is proposed. First, we consider a fractional order system without delay for which a sliding surface is proposed based on fractional integration of the state. Then, a stabilizing switching controller is derived. Second, a fractional system with state delay is considered. Third, a strategy including a fractional state predictor input delay compensation is developed. The existence of the sliding mode and the stability of the proposed control design are discussed. Numerical examples are given to illustrate the theoretical developments.     

Modeling of the multi-cable supported arch and a novel technique to investigate the natural vibratory characteristics

A fully analytical model of the multi-cable supported arch (MSA) is presented and a parametric study of the structural parameters on the planar natural vibratory characteristics is performed. Unlike the existing models, the structure is modeled with the idea “dividing the whole into parts, assembling the parts to whole” to simulate the stayed cable erection construction of the arch bridge. The global MSA under both the cantilever state and the closed state is divided into a series of chained cable-arch substructures along the span direction, The Hamilton principle is used to build the model of each substructure, in which the cable and arch segment are defined in local and global Cartesians, respectively. By assembling the equations of all substructures through the match conditions and boundary conditions, the global equation is established. Also, the global characteristic equation is determined by the transferring of coefficients vectors of substructures and some coordinate transformations. In each substructure, the interaction between the cable and the arch segment are isolated and the mutual effects are considered in the connected matrix of the coefficients vectors. The unification of the substructures converts to the transferring of the arch segments. This substructure transferring technique (STT), which is compared and verified by the finite element method (FEM), is able to effectively acquire the frequencies and the modes. The results show the sag-to-span ratios and inclined angles of the cables play significant role on the veering phenomenon in some specific intervals. Local and global modes exist simultaneously in the frequency spectrum, the involved resonant zone and veering area is needed to avoid in the parametrical design for structural safety.     

Fractal microstructure of Ag film via plasma discharge as SERS substrates

According to the atmospheric pressure plasma (APP) technology, we propose a rapid synthetic approach of the substrates for enhanced Raman spectroscopy. The plasma is used to modify and etch the surface of silver film, which generates large scale hotspots' aggregation. By switching the discharge polarity and adjusting the film thickness, different surface morphologies are formed due to the oxidation, reactive etch and accumulation of the plasma product in a certain space. Especially under positive corona discharge condition, dense snake-like microstructures are formed by the gradual connection of individual nanoparticles, which are driven by the influence of the electric field on surface diffusion. In addition, the experiments verify that the corresponding enhancement factor (EF) raises at least five orders of magnitude and the treatment time is about 10 min.