A Simple Method for the Growth of Very Smooth and Ultra-Thin GaSb Films on GaAs (111) Substrate by MOCVD

We present a simple thermal treatment with the antimony source for the metal–organic chemical vapor deposition of thin GaSb films on GaAs (111) substrates for the first time. The properties of the as-grown GaSb films are systematically analyzed by scanning electron microscopy, atomic force microscopy, x-ray diffraction, photo-luminescence (PL) and Hall measurement. It is found that the as-grown GaSb films by the proposed method can be as thin as 35 nm and have a very smooth surface with the root mean square roughness as small as 0.777 nm. Meanwhile, the grown GaSb films also have high crystalline quality, of which the full width at half maximum of the rocking-curve is as small as 218 arcsec. Moreover, the good optical quality of the GaSb films has been demonstrated by the low-temperature PL. This work provides a simple and feasible buffer-free strategy for the growth of high-quality GaSb films directly on GaAs substrates and the strategy may also be applicable to the growth on other substrates and the hetero-growth of other materials.     

JMAWR: joint optimization of monitoring trail allocation and wavelength routing with limited monitoring resources

In all-optical networks, monitoring trail (m-trail) has long been proposed as an effective way for link failure localization. Previous works tried to minimize the number of used m-trails for localizing network-wide single link failures, and they all supposed that the monitoring resources were enough. However, failures are rare events and the traffic demand is increasing rapidly. The dedicated wavelengths for m-trails cannot be used to transmit data traffic, and some traffic demand may not be served during the peak period. Considering the operators prefer to serve customers’ demand as much as possible, if the resources allocated for m-trails are limited, more traffic will be carried. In this paper, we focus on the scenario where there are not enough resources for allocating m-trails. In this scenario, as only part of single link failures can be unambiguously localized, we aim to monitor the most valuable links, which carry more traffic demand, and minimize the maximum number of used wavelengths for traffic demand on the links which cannot be unambiguously localized. As we can also control the wavelength routing for traffic demand, we try to jointly optimize the m-trail allocation and wavelength routing. We first formulate this joint optimization problem as a mathematical model and present concrete analyses on this model. According to these analyses, a joint m-trail allocation and wavelength routing (JMAWR) heuristic algorithm is proposed based on graph-constrained group testing. Simulation results show that JMAWR outperforms the state-of-the-art m-trail allocation algorithm by up to 88.46% improvement in terms of maximum number of used wavelengths for traffic demand on links which cannot be unambiguously localized.     

Highly Efficient Three Primary Color Organic Single‐Crystal Light‐Emitting Devices with Balanced Carrier Injection and Transport

Organic single crystals have a great potential in the field of organic optoelectronics because of their advantages of high carrier mobility and high thermal stability. However, the application of the organic single crystals in light‐emitting devices (OLEDs) has been limited by single‐layered structure with unbalanced carrier injection and transport. Here, fabrication of a multilayered‐structure crystal‐based OLED constitutes a major step toward balanced carrier injection and transport by introducing an anodic buffer layer and electron transport layer into the device structure. Three primary color single‐crystal‐based OLEDs based on the multilayered structure and molecular doping exhibit a maximum luminance and current efficiency of 820 cd cm^?2 and 0.9 cd A^?1, respectively, which are the highest performance to date for organic single‐crystal‐based OLEDs. This work paves the way toward high‐performance organic optoelectronic devices based on the organic single crystals.     

观测距离及视角对红外热辐射检测的影响研究

观测距离和视角是影响红外热辐射检测精度的两个关键参量.为评估观测距离和视角对红外热像仪测温精度的影响,实验测量了不同观测距离和视角条件下的温度,并对测量的实验结果进行了分析.结果表明随着目标的观测距离和视角的增大,红外热像仪的测温精度均出现一定程度降低,通过对实验数据进行拟合补偿了距离和视角造成的误差.     

Role of zinc in regulating the testicular function. Part 1. Effect of dietary zinc deficiency on serum levels of gonadotropins, prolactin and testosterone in male albino rats

Hypogonadism is a major manifestation of zinc deficiency in both humans and animals. In this study, we try to elucidate the main role of zinc in regulating the testicular function. Ninety male weanling albino rats were divided into three groups: control, zinc-deficient (ZD), and zinc-supplemented (ZS) groups. Six rats from each group were sacrificed every two weeks over a total period of ten weeks. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL) and testosterone (T) were estimated by radioimmunoassay technique. Serum zinc concentrations were also determined. Data revealed that serum zinc concentrations were significantly low in ZD group compared to both control and ZS groups. Normal FSH and LH but low PRL and T levels were demonstrated in sera of ZD group compared to both control and ZS groups. We came to the following conclusions: zinc deficiency has no effect on the pituitary gonadotropin output. Zinc deficiency affects the testicular function either directly through its effect on the testicular steroidogenesis and/or indirectly through its effect on the pituitary synthesis and/or secretion of PRL.     

高速针梳机用于加工绢纺老工艺绵条的探索

通过单机试验和两条工艺流程的对比表明,采用DJ432——DJ432——DJ442的工艺流程,比较适合于老工艺;认为只要对DJ型高速针梳机作适当改进,完全可以取代CZ型条机加工老工艺绵条,成为新、老工艺均能适用的通用机型。     

一个改进的N元自适应模式识别系统开发工具

N元自适应模式识别系统开发工具NIRSS是一个通用开发工具.它可以对多种N元自适应模式识别系统模型的体系结构和应用对象进行试验研究.本文针对该系统的不足,提出采用修改编译模式并利用EMS技术扩大存贮容量的方法,使其具有处理高维数模式数据(如图像)的能力.实验证明,改进工作是成功且有意义的.     

波导系统模式的分析与鉴别

介绍了现有各种模式分析的方法,比较了它们各自的特点,认为模式耦合鉴别方法具有实时性与动态性的优点,尤其适合高功率微波系统应用。     

A system for the exposure of small laboratory animals to a 25-mT60-Hz alternating or traveling magnetic field

A versatile exposure system which can be used to investigate the effects of a 60-Hz alternating magnetic field or traveling magnetic field on small laboratory animals is described. Special attention was given to the design of the electric circuit to simplify the supply requirements and to keep the overall current to a minimum. A magnetic field having a flux density up to 30 mT (300 G) can be generated, and a traveling magnetic field is obtained by reconnecting the coils to a three-phase supply. The total magnetic field due to the currents in the three coils used in the exposure system is analyzed. A computer program was written to evaluate the magnetic field in the region where the animals are located. The difference observed between measured and computed values is attributed to the representation of the multiturn, multilayer coils by equivalent single-turn coils     

基于WiMAX技术的宽带WMAN及其应用

随着计算机和无线通信技术的迅猛发展,尤其是考虑到用户对高速业务、终端移动与漫游的强烈需求,信息网络的基础设施正在快速向无线联接、无缝覆盖的目标迈进。其中,蜂窝移动通信系统和无线局域网(WLAN,Wireless Local Area Networks)的极大成功,促使人们将目光转向传统的城域网领域;而伴随着骨干网向IP宽带化的发展和用户数据业务的快速增长,