连续输出20WAlGaAs／GaAs量子阱激光二极管线列阵

采用ＭＯＣＶＤ实现了ＡｌＧａＡｓ／ＧａＡｓ量子阱结构，获得了连续输出２０Ｗ激光二极管线列阵，线列阵长度１．０ｃｍ，激射波长８０８±４ｎｍ。     

A three-dimensional non-epitaxial atomistic growth model for thin-film deposition: effect of surface mobility

The effect of the atomic mobility on a film surface has been studied by using a three-dimensional atomistic thin-film deposition model which simulates three-dimensional thin-film images, surface profiles and cross-sectional area pictures. In addition, quantitative results of surface RMS roughness, average film thickness, atomic coordination number and its distribution, and solid fraction of the deposited thin films, were obtained from the simulations. When the film surface mobility increased from 0.3 to 3.0, RMS roughness decreased from 6.5 to 1.1, solid fraction increased from 0.27 to 0.56 and average film thickness decreased from 40 to 28, due to the reduction of the voids within the film. The full-width half magnitude of the atomic coordination distribution became narrower indicating the increased degree of crystallization. With increase in surface mobility crossing the boundary to 1.5, the film evolved from a porous or loose columnar structure with voids, to a densely packed fibrous grain structure which can be categorized by the zone structure models.     

Overcharging: keeping both feet on the ground and going a step forward

The intrinsic value of animals and their place in human society influence veterinary practice. The role-responsibility of the veterinarian is under pressure of practical circumstances, client requests and constraints of breeding and management systems. A reflection on human needs as related to the intrinsic value and welfare of animals, is required inside and outside the profession. It is in the interest of life to think and act out of total ecological concepts. In order to be better prepared to deal with ethical problems in practice, students should receive adequate training. The assumed value-free research and the need for outside financial support are a hindrance for research projects that aim at sustainability of human and animal life. It is concluded that the profession needs a philosophy about her objectives.     

Retroviral display of antibody fragments; interdomain spacing strongly influences vector infectivity

Five different single-chain antibody fragments (scFv) against human cell-surface antigens were displayed on murine ecotropic retroviral vectors by fusing them to the Moloney SU envelope glycoprotein. The spacing between the scFv and the SU glycoprotein was varied by fusing the scFv to residue +7 or to residue +1 of Moloney SU and by inserting linker sequences of different lengths between the domains. All of the chimeric envelopes were efficiently incorporated into vector particles and could bind to human cells through their displayed antibody fragments, but did not infect them. The spacing between the scFvs and the SU glycoproteins had no significant effect on the efficiency of envelope expression or viral incorporation and did not affect the binding properties of the chimeric envelopes, nor did it influence the efficiency of targeted gene delivery to human cells by scFv-displaying vectors. However, on murine fibroblasts the infectivity of vectors incorporating the chimeric envelopes was strongly influenced by the length of the interdomain spacer. The titers were very low when the single-chain antibodies were fused through a tripeptide linker to SU residue +7 and were greatly enhanced (up to 10(5)-fold) when they were fused to SU residue +1 through a heptapeptide linker. These results point to the importance of steric interactions between the domains of chimeric envelope glycoproteins and may have implications for retroviral vector design for human gene therapy.     

GaN的MOVPE生长和m－i－n型蓝光LED的试制

利用自行研制的常压ＭＯＶＰＥ设备和全部国产ＭＯ源，采用低温生长缓冲层技术，在蓝宝石（α－Ａｌ２Ｏ３）衬底上获得了高质量的ＧａＮ外延层。未掺杂的ＧａＮ外延层的室温电子迁移率已达１１４ｃｍ２／Ｖ．ｓ，载流于浓度为２×１０１８。７７Ｋ光致发光谱近带边发射峰波长为３６５ｎｍ，其线宽为４ＤｍｅＶ。Ｘ射线双晶衍射回摆曲线的线宽为３６０ａｒｃｓｅｃ。用Ｚｎ掺杂生长了绝缘的ｉ－ＧａＮ层。在此基础上研制了ｍ－ｉ－ｎ型ＧａＮ的ＬＥＤ，并在室温正向偏压下发出波长为４５５ｎｍ的蓝光。     

Independent modulation of horse airway smooth muscle by epithelium and prostanoids

The effects of epithelial removal and cyclooxygenase inhibition on contractions induced by exogenous acetylcholine (ACh) and electrical field stimulation (EFS) were evaluated in horse tracheal strips and bronchial rings. Epithelial removal potentiated the response to ACh but had no influence on the response to EFS. The effect of epithelial removal was not altered by pretreating the tissues with meclofenamate, a cyclooxygenase inhibitor. In trachealis strips, meclofenamate augmented contractions induced by EFS but not by ACh. In bronchial rings, meclofenamate augmented EFS-induced contraction to a greater extent than ACh-induced contraction. These effects of meclofenamate were epithelium-independent. We conclude that horse airway epithelium produces a relaxant factor that is not a prostanoid. Endogenous prostanoids originating from non-epithelial sites inhibit only cholinergic nerves in the trachea but both parasympathetic nerves and smooth muscle in the bronchi.     

用硫磺盖帽电探针测定工业炸药爆轰压力

文中介绍了利用硫磺盖帽电探针测定工业炸药爆轰压力的方法，并对煤炭工业常的４类１１个品种炸药的爆轰压力进行了实际测量。     

排列互比法用于超精测角的研究

作者分析了我互比法现行的两种数据处理方法的缺点，提出了应用最小二乘法原理推导出合理的数据处理方法。本文还首次从理论上阐明了排列互比法测量结果中出现一次谐波系统误差的原因，提出了减少和消除这一些系统误差的方法，并给实验验证。     

Fe－Cu包埋团簇的制备及其微观结构的研究

基于溅射－气体－聚集（ＳＧＡ）形成团簇的原理，提出了蒸发－气体－聚集（ＥＧＡ）共沉积方法，并在方华膜载网上成功地制备了Ｆｅ－Ｃｕ纳米磁性包理团簇样品。ＴＥＭ／ＥＤ分析表明，样品中Ｆｅ团簇被Ｃｕ原子所包裹，形成了以Ｆｅ团簇为芯，Ｃｕ膜为壳的良好的芯－壳式包埋结构。当衬底温度由２５℃变化到２００℃时，样品形貌由弥散状过渡到集团状，直至形成大的块状；其结构也相应的由Ｆｅ－Ｃｕ多晶共存变化为一种不规则的单晶形态。