金属光电效应逸出功简要分析

大学物理教材中对光电效应下的定义不准确,对光电子是否有最大初动能存在两派观点,通过对金属逸出功的分析,表明光电子存在最大初动能。     

基于虚拟仪器的计算机控制步进电机系统的设计

在扫描探针显微镜系统中,本文采用基于虚拟仪器的计算机控制步进电机,控制它的正转、反转及启动和停止,从而实现样品与探针的自动逼近。利用计算机通过I/O接口来直接产生各种方波信号,采用L abV IEW编程完成控制算法,以此来实现步进电机运动,提高了逼近系统的自动化性能和控制精度。     

插件技术在安全扫描系统中的应用

针对安全扫描系统软件升级难的问题,提出了采用插件技术构建分布式网络安全扫描系统的方法,将漏洞以插件方式实现,通过更新漏洞插件来更新扫描系统,及时发现安全漏洞;并阐述了运用插件技术来构建分布式网络安全扫描系统的过程.     

鸭绿江茴鱼鳃的扫描电镜观察

用扫描电镜对鸭绿江茴鱼（Thymallus arcticus yaluensis）鳃的表面结构特征进行了详细的观察.结果表明：鳃耙、鳃弓、鳃丝及鳃小片细胞都有不同形状的隆嵴和刻纹等结构;鳃耙上有两种刺状骨质突起;鳃弓上有大小不同的空洞;鳃小片的上皮细胞表面凸凹不平;鳃丝上皮细胞隆起和刻纹较为发达,这些形态结构是与它的生理功能及生活习性密切相关的.     

基于P-范分布下的三维激光点位误差分布检验

目前,在对三维激光点位误差模型进行推导的过程中,都是假设三维激光点位误差是服从正态分布的,而由于三维激光点位误差源与传统测量仪器中的误差源不同,同时外界环境对激光点位误差的影响也不相同,因此,不能直接断定点位误差服从正态分布,需要对其理论分析及数据统计分析验证。针对三维激光点位误差分布状况,本文对激光点位误差模型进行了推导,并通过大量数据统计分析验证了激光点位误差服从的分布状况。     

企业集中式网络漏洞扫描模式的研究与应用

本文对网络漏洞扫描方法进行深入研究,以某大型国企的安全管理方式,研究并建立了一体化集中式漏洞扫描模式。通过硬件平台部署、软件平台研发,成功实现了模型的应用。本文对具有异地分支机构的企业,在其内部信息网络的安全漏洞管理方面具有一定的借鉴作用。     

Chinese archaeological artefacts: Microstructure and corrosion behaviour of high-leaded bronzes

Metallographic features of ancient bronze artefacts often hide peculiar micro-chemical processes and corrosion behaviours, which are worth to be studied as they can provide conservators and archaeologists with valuable tools and information. It is widely documented that Chinese bronzes were cast and the way to adjust their properties was to change the alloy composition. In particular, addition of lead, which is insoluble in the bronze matrix, results in the formation of inclusions or globules, which undergo oxidation processes leading to their conversion into corrosion products. The mechanisms through which this occurs were still poorly investigated. The present work was conducted to further study the corrosion behaviour of high-leaded bronze, especially focusing on the behaviour of lead globules. To this aim, a collection of Chinese archaeological bronzes, showing intermediate steps of degradation, were selected and investigated. The use of combined microscopy-based, molecular and elemental, analytical techniques allowed the characterization as well as the precise location of corrosion products, thus enabling us to propose a degradation pathway basing on thermodynamic data provided by Pourbaix diagram. The achieved results will be useful for researchers involved in these kinds of studies to better interpret data obtained.     

也谈图式与阅读能力的培养

本文通过分析阅读教学中的设问及其与图式的关系,探讨这些图式对阅读四大技能——略读、寻读、细读和批评性阅读的培养所起的作用,然后提出如何利用和完善这些图式来提高阅读理解能力。     

Microstructure of ferrospheres in fly ashes: SEM, EDX and ESEM analysis

Ferrospheres in fly ashes from a coal-fired power plant were extracted by a magnetic separation technique and their microstructure was studied by scanning electron microscopy （SEM）, energy dispersive X-ray analysis （EDX） and environmental scanning electron microscopy （ESEM）. Ferrospheres in fly ashes show significant iron enrichment compared to their respective fly ashes. Iron oxides in ferrospheres mainly occur as minerals magnetite （Fe3O4） and hematite （α-Fe2O3）, which are derived mainly from the decomposition and oxidation of iron-bearing minerals in coal during combustion. EDX data indicate that ferrospheres also contain Si, S, Al and Ca resulting from quartz, mullite, anhydrite and amorphous materials. A large percentage of ferrospheres are commonly 5-50 μm in size. The microstructure of ferrospheres includes smooth, polygonal, dendritic, granular and molten drop characteristics. SEM coupled with EDX provided fast and accurate results of the microstructure and chemical composition of ferrospheres, and helped us to assess environmental issues related to the disposal and utilization of fly ashes.     

Bubble counter based on photoelectric technique for leakage detection of cryogenic valves

In order to overcome the inconvenience of manual bubble counting, a bubble counter based on photoelectric technique aiming for automatically detecting and measuring minute gas leakage of cryogenic valves is proposed. Experiments have been conducted on a self-built apparatus, testing the performance with different gas inlet strategies （bottom gas-inlet strategy and side gas-inlet strategy） and the influence of gas pipe length （0, 1, 2, 4, 6, 8, 10 m） and leakage rate （around 10, 20, 30, 40 bubbles/min） on first bubble time and bubble rate. A buffer of 110 cm^3 is inserted between leakage source and gas pipe to simulate the downstream cavum adjacent to the valve clack. Based on analyzing the experimental data, experiential parameters have also been summarized to guide leakage detection and measurement for engineering applications. A practical system has already been successfully applied in a cryogenic testing apparatus for cryogenic valves.