纳米银敷料无菌检查方法

依据《中国药典》2005年版二部附录无菌检查法进行试验,建立适合于纳米银敷料的无菌检查方法。采用直接接种法,对14批纳米银敷料进行无菌方法学验证,结果表明使用规格40mL的培养基、每管培养基接种量为1cm×3cm时,纳米银敷料无明显抑菌作用,可按此方法进行无菌检查。     

铝合金薄壁件数控铣削加工变形试验与分析

薄壁工件刚度差,在数控加工过程中在切削力的作用下极易产生加工变形,影响工件加工精度和成本。在THA5656立式加工中心上对铝合金材料LY12CZ方形直侧壁工件变形进行了试验研究,并进行误差分析。通过正交试验,研究薄壁件在铣削精加工过程中各个切削用量情况下工件的变形情况,为提高生产率和进一步控制加工变形和验证加工过程计算机仿真模型提供依据。     

编程实现检测报告成批快速输出

样品检测完成后,要求快速准确出检测报告,如果不能及时出检测报告,将使客户的产品不能按时出口,受到经济损失,而且降低了客户的信用。显然,手动打印检验报告,容易出错,工作量大,满足不了需要,为了解决这一问题,通过编程实现检测报告成批快速输出,既提高了工作效率,又减轻了劳动强度,保证了检测报告数据准确性,检测报告规范和标准,在实际应用中取得了良好的效果。     

自动化仓库的发展现状及展望

自动化仓库,又被称为“立体仓库”,它与自动分拣系统和自动导向车并称为物流技术现代化的三大标志。自动化仓库具有提高空闻利用率及货物管理质量,提高劳动生产率,降低劳动强度等优点。     

基于虚拟仪器技术的汽车离合器综合性能测试系统研究

基于虚拟仪器技术设计了汽车离合器综合性能测试系统。阐述了测试系统的总体结构和工作原理;为了提高检测精度和效率,设计了参数自整定的模糊PID控制器对系统进行控制,并采用卡尔曼滤波方法对信号进行滤波;基于NI公司虚拟仪器技术开发了测试系统软件。经仿真及实际应用验证,测试系统的检测精度和检测效率得到了较大提高,测试结果准确、可靠。     

磁分离水处理装置的研制

为了实现富营养化水体的根治目的,在分析水处理工艺的基础上,结合磁分离技术设计了一种高效率的水处理装置,并且已经获得了国家专利1。在实际试验中验证了该装置的处理效果,经过处理的水体达到国家三类水质标准。     

Using the concept of a measurement system to characterize measurement models used in psychometrics

The philosophy of measurement in the social and behavioral sciences is seen (from without) as typically following the representational viewpoint. However, in practice, this is not the case for the great majority of measures that are developed in this area. The paper surveys several approaches to measurement in the social sciences (i.e., Classical Test Theory, Guttman Scaling, Item Response Theory, Rasch Scaling, and Construct Modeling), as examples of measurement approaches in the area of psychometrics, and uses the foundational concept of a measuring system, as developed by Mari [1], to explicate the logic on which these approaches are based and thus enable a comparison with measurement approaches used by other fields such as engineering and physics. The paper uses the underlying concept of the standard reference set (one of the essential features of Mari’s formalization) to show how the five approaches differ, and also how they are related. The importance of these differences, and the consequences for measurement using those approaches are also explicated and discussed.     

Test bed for power amplifier behavioral characterization and modeling

Traditional test bed of power amplifier (PA) behavioral characterization and modeling based on vector signal analyzer (VSA) and often equipped with specialized software is both expensive and inflexible to modify to suit different scenarios. In this paper, a new test bed based on an oscilloscope or other general purpose data acquisition systems, which works as analog to digital converter (ADC) with a proper (radio frequency) RF bandwidth and maximum sampling rate, is proposed. The common impairments, e.g. transmitter IQ imbalances, channel delay, frequency offset, and carrier phase offset, are all well compensated. The accurately recovered envelopes of the PA’s input and output signals are used for a PA behavioral characterization and modeling. Furthermore, Relative envelope error (REE) parameter is proposed to evaluate the accuracy of envelope recovery. The experiment shows a very accurate RF signal envelope recovery, and a good performance of PA behavioral modeling.     

Extreme Pressure Lubrication and Wear. The Chemical Reactivity and the Extreme Pressure Action of Two Aliphatic Disulfides

Reaction rates were studied for the action of di-tert-octyl disulfide and di-n-cetyl disulfide in white oil on iron powder over the temperature range 165–250 C. The data were fitted to the Arrhenius equation, and the tertiary disulfide was found to be 1500 times as reactive as the normal disulfide. White oil solutions of the two disulfides were subjected to the Falex test and to the four-ball extreme-pressure test, and the tertiary disulfide was found to be the more effective lubricant additive in these tests. Wear studies were carried out with a pin and disk apparatus under conditions which approximated the above bench tests as regards specimen material, rubbing speed and pressure. The complex nature of the course of wear made it difficult to compare the two disulfides quantitatively. It was found that the tertiary disulfide was 2 to 20 times as efficacious as the normal disulfide in reducing the terminal steady-state wear rate. By treating the additive action of the disulfides as a competition between the rate of metallic adhesion and the rate of chemical reaction with iron, it is possible to reconcile the wide discrepancy between the relative chemical reactivity and the relative additive action of the two disulfides in a quantitative fashion.     

Tribological Investigation of the Polymer-Based Lubrication System Using a Laboratory Reciprocating Bench Test

Flooded oil lubrication systems are commonly utilized for many manufacturing processes. However, there is an increasing concern with the flooded lubrication systems due to their biological and environmental impact as well as their maintenance and disposal cost. Polymer-based material, a sponge-like solid lubricant allowing the oil to weep out while in use, provides a promising alternative environmentally benign lubrication solution to satisfy the lubrication requirements for some manufacturing processes. In addition, it can minimize contamination of the coolant system, reduce waste processing and disposal costs, and alleviate the in-plant safety hazard from oil leakage on floor surfaces.

The goal of this study is to develop and improve the current lubrication system by applying a polymer-based near-dry lubrication system in order to replace the oil-flooded transfer line lubrication systems currently in production use. Using a laboratory reciprocating bench test based on the design of experiments, this study characterized the tribological performance of the polymer-based lubrication system under a variety of operating conditions, identified the main factor that impacts the tribological performance of the polymer-based lubrication system, and developed a model to predict the wear loss of the polymer-based lubricant plate. These results provide the guidelines for possible applications of the polymer-based lubrication system used in the manufacturing process.