共查询到20条相似文献,搜索用时 468 毫秒
1.
2.
洁净室日常沉降菌检测的探讨 总被引:1,自引:0,他引:1
讨论洁净室沉降菌检测的影响因素,保证检查的结果能够真实地反映洁净室的微生物情况,掌握洁净室的洁净状况。结论:在适当的设备保障下,对洁净室关键区域和最差区域进行检测,更能够掌握洁净室微生物状态,为药品生产提供环境保障。 相似文献
3.
When micro-organisms are found in nature they are frequently accompanied by other matter including organic and inorganic particles. Also, the organisms are extremely dilute so that to examine them it is necessary to grow them or to concentrate them by some means. The disadvantage of growing them is that a suitable nutrient must be known and time is needed. With the introduction of ferrography it has become possible to separate micro-organisms from other participate material by chemically magnetizing the organisms and recovering them with the Ferrograph. The chemistry of organism magnetization is discussed and examples given. The recovery of five species of bacteria is described. The separations of eukaryotic from prokaryotic cells as well as the separation of white from red blood cells are also demonstrated. 相似文献
4.
Multi-parameter flow cytometry was investigated for the rapid detection of specific serotypes of salmonellas (S. typhimurium and S. montevideo) labelled with fluorescent monoclonal antibodies, both in pure culture and in a typical food matrix (full-fat milk). In all cases, the method was accurate to levels of below 104 target cells per ml for a total assay time of about 30 min. After 6 h non-selective enrichment in the presence of a 10 000-fold excess of competing micro-organisms (Escherichia coli) the corresponding detection limit was about 20 cells ml?1. These results suggest that flow cytometry has significant potential for the detection of pathogenic micro-organisms in the food industry. 相似文献
5.
Scanning electron microscopic observations were made on the micro-organisms of root nodules of Tribulus terrestris L. The results showed that nodules of T. terrestris contained dual infection consisting of Rhizobium sp. and Newmania karachiensis. Based on these observations, T. terrestris should be grouped with nonlegume Parasponia-type bacterial nodules. 相似文献
6.
对液态密封垫片应用技术进行了详细介绍,主要涉及液态密封垫片的特点、不同类型液态密封胶的选择、法兰面的设计要求、液态密封胶的施工工艺等,最后对液态密封胶在发动机上的应用做了简单概述。通过液态对密封胶技术的介绍,为液态密封胶的正确使用提供了指导性意见。 相似文献
7.
8.
探索和研究高效液压传动技术,提高其综合性能是全世界液压界关注的重要课题之,本文从液压泵、管路、电机和油缸等几个方面对液压系统的能量损失和传动效率进行了分析和研究. 相似文献
9.
喷射成形生产中漏包连续移液及其液位控制研究 总被引:1,自引:1,他引:1
研究了喷射成形产业化生产中漏包连续移液和精确液位控制的系统结构、控制流程及控制算法。提出了双中间包交替倾倒的漏包自动连续移液方法,通过设置液位状态位置传感器以及建立相应的控制流程解决了双包切换过程的断流问题,在此基础上提出了各喷射工艺阶段的液位控制策略,采用积分分离PID算法实现漏包液位的精确控制。采用PLC开发的液位控制系统在喷射成形生产中得到很好应用,液位最大超调量为10 mm,稳态误差为±3 mm,最大PID调节时间为20 s。 相似文献
10.
11.
12.
如何降低空气对液压系统的危害 总被引:1,自引:0,他引:1
本文在深入分析空气对液压系统的危害性及其产生机理的基础上,研究了传统的液压系统利用油箱和消泡剂消除空气2种方法的弊病所在,介绍了一种防空气入侵和空气消除的技术与装置,为降低空气对液压系统的危害提供了一种新的途径。 相似文献
13.
14.
15.
提出把磁流变液作为电动机软启动装置的工作介质,介绍了磁流变液的特性,利用磁流变液屈服应力的Bingham塑性模型,分析了用磁流变液实现电动机软启动的原理,推导了磁流变液软启动器传递力矩的计算公式。 相似文献
16.
17.
18.
论述了集中供液系统中使用的金属切削液。通过加强对供液系统的净化以及浓度,pH值等方面的管理,可实现切削液的长寿命,高效益。 相似文献
19.
Application of PCA-based hybrid Taguchi method for correlated multicriteria optimization of submerged arc weld: a case study 总被引:1,自引:1,他引:0
Saurav Datta Goutam Nandi Asish Bandyopadhyay Pradip Kumar Pal 《The International Journal of Advanced Manufacturing Technology》2009,43(3-4):276-286
Fluid dispensing is a method by which fluid materials, such as epoxy, adhesive, and encapsulant, are delivered in a controlled manner in electronics packaging. This paper presents a brief review of past and recent developments in the modeling and control of the time-pressure fluid dispensing process. In particular, the characterization of the fluid flow behavior is addressed by reviewing several promising models from both time-independent and time-dependent perspectives. In the modeling of the time-pressure fluid dispensing process, various approaches for representing the flow rate of fluid dispensed and the profile of fluid formed on target are examined; and the issues involved are identified. In the control of time-pressure dispensing process, a brief review of various control methods is presented along with their limitations. The challenges associated with this control problem are also discussed. This paper is concluded with the recommendations of research in the future. 相似文献