Bi-Sb-Te基热电薄膜温差电池离子束溅射制备与表征

本文采用离子束溅射Bi/Te和Sb/Te二元复合靶,直接制备n型Bi₂Te₃热电薄膜和p型Sb₂Te₃热电薄膜.在退火时间同为1 h的条件下,对所制备的Bi₂Te₃薄膜和Sb₂Te₃薄膜进行不同温度的退火处理,并对其热电性能进行表征.结果表明,在退火温度为150 ℃时,制备的n型Bi₂Te₃关键词： 薄膜温差电池 2Te₃薄膜')" href="#">Sb₂Te₃薄膜 2Te₃薄膜')" href="#">Bi₂Te₃薄膜 离子束溅射     

垂直入射几何条件下氦原子(e,2e)反应的理论研究

用BBK模型和修正后的BBK模型在电子垂直入射几何条件下对氦原子的三重微分散射截面进行了理论计算,并把计算结果与实验测量结果进行比较,对截面的结构进行了分析,并对交换效应进行了系统的研究. 关键词： DS3C模型 中间峰 屏蔽效应 交换效应     

一种改进的无链表3DSPITH算法用于高光谱图像压缩

 针对大孔径静态干涉成像光谱仪(LASIS)的成像特点,提出了一种基于三维非对称等长树小波变换的无链表SPITH算法结合ROI的图像压缩方案。首先,对干涉高光谱图像进行三维非对称等长树离散小波变换。其次,采用ROI方法对主要的光谱系数进行保护。最后,采用改进的三维无链表SPITH算法,编码干涉高光谱图像的小波变换域。实验结果表明,该方法在8∶1压缩比下,获得大于40 dB的平均峰值信噪比,同时有效地保护了光谱信息。     

Alteration of skin light-scattering and absorption properties by application of sunscreen nanoparticles: A Monte Carlo study

We report about the results of our investigations on the alteration of optical properties of the superficial layer of human skin at four UV range wavelengths, 310, 318, 360 and 400 nm, by application of 35-200 nm-sized particles of titanium dioxide (TiO₂), silicon (Si) and zinc oxide (ZnO). The theoretical study based on combination of the Mie theory and Monte Carlo simulations reveals the optimal sizes of the nanoparticles minimizing the light transmittance for the considered wavelengths.     

Constitutive theories for nonlocal micropolar continua with implicity and with multiple interactions

In this paper the constitutive theory for nonlocal micropolar continua which was proposed by A. C. Eringen is extended to the cases for nonlocal micropolar continua with implicity and with multiple interactions. Here nonlocal micropolar thermoelastic solids with implicity and with multiple interactions are cited as instances to illustrate the procedure for the establishment of their constitutive theories as well as two relevant theorems concerning the constitutive theories for those solids are given.     

液相沉积法制备光催化活性TiO2薄膜和纳米粉体

采用液相沉积法，在35℃通过向六氟钛酸铵水溶液中添加硼酸和结晶诱导剂锐 铁矿型TiO2纳米晶，沉积出具有光催化活性的Ti02薄膜和纳米粉体．用XRD，AFM， 阶梯仪,UV-vis，BET法对Ti02薄膜和粉体的沉积条件、结构、厚度和性能进行了测 定和表征，并用亚甲兰的降解，评价了TiO2薄膜和纳米粉体的光催化活性．结果表 明，当反应物六氟钛酸铵与硼酸的摩尔比为1：2—1：4时，沉积的粉体和薄膜含有 锐钛矿相Ti02；经300℃热处理的Ti02薄膜和纳米粉体具有最高的光催化活性，它 的光催化活性是未经热处理前的5倍．本文还解释了经300℃热处理的薄膜和纳米粉 体具有最高光催化活性的原因．     

群柱内酯萜二维核磁共振谱的研究

本文研究了群柱内酯萜(Ⅰ)的二维¹H同核COSY、C-H COSY、远距C-H COSY谱,根据这些信息和经验规律归属了(Ⅰ)的¹H及¹³C谱峰,二维远距C-H COSY提供了相隔两、三个键的C-H偶合信息,因此,在很多方面可以代替灵敏度很低的INADEQUATE技术,得到C-C联结的信息。     

Effect of microstructure on thermoelectric properties of CSD-grown Bi2Sr2Co2Oy thin films

Three Bi₂Sr₂Co₂O_y thin films with different microstructures have been prepared by chemical solution deposition on LaAlO₃(001) through varying the annealing temperature. With the decrease in the annealing temperature, both the size and c-axis alignment degree of grains in the film decrease as well, leading to an increase in the film resistivity. In addition, the decrease in the annealing temperature also results in a slight increase in the seebeck coefficient due to the enhanced energy filtering effect of small-grain film. The nanostructured Bi₂Sr₂Co₂O_y film with the average grain size of about 100 nm shows a power factor comparable to that of the films with larger grains. Since the thermal conductivity of the nanostrcutured films can be depressed due to the enhanced phonon scattering by grain boundary, a higher figure of merit is expected in Bi₂Sr₂Co₂O_y thin film with grains in nanometer size.     

Some neutral current effects in an SU(3)×U(1) gauge model

The anomalous magnetic moment of muon is calculated in anSU(3)×U(1) gauge model proposed by Gupta and Mani. We find the contribution due to the intermediate gauge bosons to be of the same order of magnitude as in Weinberg. Salam model. The deep-inelastic structure functions are also analysed in the same model and inequalities for the structure functions are obtained in the light-cone algebra approach.     

Reinvestigation of the second negative (A 2 Π u−X 2 Π g) band system of O 2 +

TheA ² Π _ustate of O₂ ⁺ was earlier established as an inverted state contrary to previous assumptions. The rotational analysis of a few more bands of theA-X system of O₂ ⁺ has now been completed. These studies show that the spin-orbit coupling constantA in theA ² Π _ustate gradually varies with the vibrational quantum numberν and is found to be positive forν⩾6. It has also been observed that the spia-rotation interaction is not negligible in theA ² Π _ustate. The spin splitting constantγ is reported for various vibrational levels of this electronic state.