光子晶体结构GaN基蓝光发光二极管结构及制作方法

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Influence of output waveguide on mode quality factor in semiconductor microlasers with an equilateral triangle resonator

Semiconductor microlasers with an equilateral triangle resonator (ETR) and an output waveguide are proposed and analyzed by the finite-difference time-domain technique and the Pade approximation. The numerical results show that microlasers with an output waveguide still have a high-quality factor (Q factor) and are suitable to realize directional emission. For the ETR with a 0.46-mum-width opening in one of the vertices connected to the output waveguide, we have the Q factor of 1.5x10(3) and 2.5x10(2) for the TM fundamental mode at the wavelength of 1.55 mum, as the side length of the ETR is 5 and 3 mum. The simulated intensity distributions are presented for the fundamental mode in the ETR with a side length of 3 mum and an opening of 0.23 mum. (C) 2000 American Institute of Physics. [S0003-6951(00)01749-6].

基于JSF的网格门户设计与实现

网格门户在推广网格应用中起了重要作用,但网格门户在诸多方面如功能和表现能力等仍有待完善。引入JavaSer-verFaces(JSF)这一新的Web框架,设计和实现了一个网格门户。利用JSF的表现能力提供了一个更为丰富的、集成的、易操作并且可定制的用户接口。并且由于JSF与其它Java技术、底层的网格技术实现无缝的衔接,实现了平台无关的、强大的网格资源管理及动态配置功能,同时使系统具有更强的可扩展性。

小兴安岭红皮云杉生长规律的研究 红皮云杉生长与光的关系及生长力旱——晚期相关

本文研究了小兴安岭红皮云杉天然林中幼苗、幼树的高生长与光照的关系，以红皮云杉幼苗、幼树到四个象限最近上层林木的距离与各自个体树高的比值之和，定义为开敞度，从而定量地分析了开敞度与相对光强和幼苗、幼树近三年高生长的关系。结果表明，开敞度与相对光强之间存在着极显著的线性关系，可用其作为林下幼苗、幼树光照条件的指标；年龄小于13龄的幼苗、幼树的近三年高生长与开敞度关系不显著，而13龄以上的幼苗、幼树的近三年高生长与开敞度之间存在着极显著的线性关系。要使小兴安岭天然林中的红皮云杉幼苗、幼树正常生长，必须使其开敞度保持在1.47以上，即要使红皮云杉幼苗、幼树与上层林木的平均距离大于这些上层林木平均树高的37%。本文在对红皮云杉树干解析资料分析的基础上，研究了红皮杉天然林和人工林生长力的早-晚期相关关系，发现天然林早期各龄阶与60年，人工林早期各龄阶与20年的生长力相关十分明显，树高和材积的总生长量可作为旱期造反的指标，通过早期造反效率的计算，确定天然林和人工林的“可靠选择年龄”分别为15年和4年。

牵拉力对共培养的表皮干细胞及成纤维细胞迁移行为的影响

<正>背景:创面愈合是一个复杂的动态过程,是细胞之间、细胞与细胞外基质及细胞因子间相互影响和协同作用的结果。另外,大量相关研究表明机械应力可以诱导组织细胞增殖,促进创面愈合。因此创面愈合也是一个典型的力学-生物学耦合过程,但力学刺激促进创面愈合的细胞/分子的调控机制目前尚不清楚。皮肤由多种细胞组成,通过牵张皮肤等在体方法难以区分其中某类细胞对外界力学刺激的单独响应以及不

步进电机控制系统的设计及其应用

介绍了基于MSP430F149单片机的步进电机控制系统的设计。在硬件部分,描述了该系统的硬件配置和工作原理;在软件部分,分析了单片机控制程序和步进电机运动的设计过程。该系统具有研制成本低且扩展好的特点,并具有软件功能强、操作使用简便等优点,满足了兰州重离子加速器冷却储存环(HIRFL-CSR)系统中对五相步进电机的各种控制要求。

图书馆统计·读者心理·潜在信息

<正> 图书馆统计、读者心理、潜在信息,看起来似乎是三个孤立的研究问题,可是在图书馆工作中,若能透过现象看本质,会发现它们常有机地联系在一起,而从中找出一些规律性的东西,将能使我们专业图书馆的工作引向深入。近来,通过工作实践,我在中科院沈阳应用生态所图书馆的图书流通部门做了一些粗略的统计:这个馆库存图书主要有中、日、俄、英4个文种。中文:52856册,西文:19314册:

Crystallization kinetics and morphology of nylon 1212

The isothermal and non-isothermal crystallization processes of nylon 1212 were investigated by polarized optical microscopy. The crystal growth rates of nylon 1212 measured in isothermal conditions at temperatures ranged from 182 to 132 degreesC are well comparable with those measured by non-isothermal procedures (cooling rates ranged from 0.5 to 11 degreesC/min). The kinetic data were examined with the Hoffman-Lauritzen nucleation theory on the basis of the obtained values of the thermodynamic parameters of nylon 1212. The classical regime I --> II and regime II --> III transitions occur at the temperatures of 179 and 159 degreesC, respectively. The crystal growth parameters were calculated with (100) plane assumed to be the growth plane. The regime I --> II --> III transition is accompanied by a morphological transition from elliptical-shaped structure to banded spherulite and then non-banded spherulite. The development of morphology during isothermal and non-isothermal processes shows a good agreement.

Preparation, characterization and antifungal properties of 2-(alpha-arylamino phosphonate)-chitosan

In this paper, 20 kinds of different 2-(alpha-arylamino phosphonate)-chitosan (2-alpha-AAPCS) were prepared by different Schiff bases of chitosan (CS) reacted with di-alkyl phosphite in benzene solution. The structures of the derivatives (2-alpha-AAPCS) were characterized by FT-IR spectroscopy and elemental analysis. In addition, the antifungal activities of the derivatives against four kinds of fungi were evaluated in the experiment. The results indicated that all the prepared 2-alpha-AAPCS had a significant inhibiting effect on the investigated fungi when the derivatives concentration ranged from 50 to 500 mu g mL(-1). Furthermore, the antifungal activities of the derivatives increased with increasing the molecular weight and concentration. And the antifungal activities of the derivatives were affected by their dimensional effect and charge density. Besides, the rule and mechanism of the antifungal activities of them were discussed in this paper. (C) 2009 Elsevier B.V. All rights reserved.