加速器质谱测量129I方法的改进

在筑波大学的12UD串列加速器上开发了一套改进的129I加速器质谱(AMS)测量方法,包括在120°磁铁后安装了一副自行设计制作有静电偏转板,有效改善了对127I束流和129I计数的测量;采用97MoO2分子导航束稳定加速器端电压,加速器的端电压能稳定在几天内不超过0.1%,结合二次剥离,取得了满意的测量效果.用该方法测得AgI试剂样品的本底水平为7.83×10-13.对129I/127I比值范围为(4.92～0.28)×10-10的一系列样品的测量不确定度在7%以下,准确度较前有所提高.     

Development of –1 MV DC Filter and High‐Voltage DC Measurement Systems for ITER NBI

This paper presents the development results of a ?1 MV dc filter and dc measurement systems for an ITER (International Thermonuclear Experimental Reactor) neutral beam injector (NBI) system. High accuracy of 0.5% and fast responsivity of 3.3 μs, ?3 dB are required for the dc measurement systems: both dc voltage dividers and DCCTs. Circuit design and thermal flow design were carried out to clarify and minimize their effects on the accuracy and responsivity. The validity of the established design was demonstrated by the actual‐product tests; temperature rise of each components fell below the allowable value; inner components of dc filter withstood dc ?1.2 MV; each voltage divider accurately measured the voltage during the dc ?1.2 MV withstand voltage test; the voltage dividers and the DCCTs were adequate to the requirements of responsivity (3.3 μs, ?3 dB).     

PARTICIPATORY ACTION RESEARCH FOR ENVIRONMENTAL HEALTH: ENCOUNTERING FREIRE IN THE URBAN BARRIO

ABSTRACT: The community‐based approach to health research and intervention is a model of inquiry rooted in Freire's participatory action research (PAR). We need to show, in concept and practice, what it is about PAR that may be well suited for the types of health issues we encounter in inner‐city environments. What type of learning results, how does this respond to particular health issues in the urban context, and what are the particular challenges faced in translating Freire's model into today's urban setting? To investigate these questions, we describe a recent PAR project in Southeast Los Angeles, California—an area known to some as “Asthmatown.” One salient finding of the research is that PAR allows the integration of complex and multiple forms of knowledge, and this is a necessary response to the complex and multiplex nature of cumulative impacts. There are challenges to translating the model to the urban setting, however, such as the difficulties of participation in today's urban milieu. The research leads to some lessons for practitioners, such as the need to build “constant” elements into PAR projects. Lastly, we reflect on implications of this model for institutional reform.     

一种推拉式防火门

分析我国规范对推拉式防火门的限制,介绍其他国家的规范要求.介绍一种新型的推拉式防火门,能克服悬挂砝码、电动驱动方式的缺陷,采用机械方式驱动滑轮.钟摆式悬吊系统所需开启力较小,可防止受挤压时的滑轨变形,可靠性较高.减速制动装置可以避免失速造成夹伤人员.关闭时引拉装置将门扇推向边框,防烟性能强.该门占地少、避免门扇对楼梯内人员的二次伤害,适用于竖井分隔和有无障碍要求的场所.     

Current Superimposition Variable Flux Reluctance Motor

This paper proposes a novel variable flux reluctance motor without dc‐field coils. The stator of this motor has only armature coils. The proposed motor can control the torque‐speed characteristics by increasing or decreasing the field voltage that is superimposed on the armature currents. In this paper, the operational principle of the motor is described, and the N–T characteristics are computed by finite element analysis under vector control. In addition, the N–T characteristics are compared with a conventional variable flux reluctance machine with armature and dc‐field coils.     

皇家经典

这是一个年轻的团队, 这是一股有理想有追求的新生力量. 我们坚信,细节决定成败.     

Viscous Sol and Gel Formation from Process Whey Protein Below 25°C

The viscosity of process whey protein (PWP; whey protein preheated under salt-free conditions) solution increased and led to gel formation with incubation at ambient or lower temperature by NaCl addition. Viscosity of PWP solution (70 mg/mL, 38.3 sec^-1, 40 min incubation) either with NaCl up to 120 mM or without NaCl decreased with increasing temperature, viscosity gave straight lines in an Andrade plot below 25°C, whereas viscosity of PWP solution with NaCl sharply increased with increase in temperature above 25°C. This suggested that association of the aggregates of PWP molecules occurred above 25°C by addition of NaCl, and that network formation by such aggregates might cause gelation.