首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 203 毫秒
1.
介绍721型分光光度计常见的光源故障、电表故障、仪器不稳定故障,以及故障排除方法。  相似文献   

2.
介绍BT-99型水质分析仪在使用过程中经常出现的故障,分析了故障产生的可能原因,并提出了故障排除方法。  相似文献   

3.
介绍谷物水分测定仪显示故障、调零故障、调不到满刻度及示值不准确故障产生的原因,以及检查步骤和故障排除方法。  相似文献   

4.
介绍ZTGC-900D型气相色谱仪使用过程中出现的几起故障,对故障进行分析、诊断,提出了故障的排除方法。  相似文献   

5.
介绍气相色谱-质谱联用仪的常见故障:与质谱仪调谐相关的故障、与校准和灵敏度相关的故障及与色谱图和质谱图相关的故障,给出了产生故障的可能原因,提出了故障排除的方法。  相似文献   

6.
介绍pHS-3型数字式酸度计常见的故障及故障排除方法。  相似文献   

7.
简要介绍贝克曼离心机触摸键盘失控和控制参数显示混乱两例故障的故障现象、故障分析以及故障排除方法。  相似文献   

8.
介绍VITALAB21型半自动生化分析仪常见故障、故障原因及故障排除方法。  相似文献   

9.
本文将“故障要因图”法应用于电镜真空系统的维修中,作出了H-800型透射电镜真空系统的故障要因图,并依据这一要因图对H-800型电镜真空系统的实际故障进行分析,比较准确地判定了故障部位,指出利用故障要因图分析和查找电镜真空系统故障的部位和原因能取得好的效果。  相似文献   

10.
GC-9790型气相色谱仪氢火焰离子化检测器的燃烧室被高沸点凝集物污染,在直流电场作用下,持续发生电离反应,形成约4000μV的基线噪声。对故障原因和故障产生机理进行了分析,提出了故障排除方法。  相似文献   

11.
The HNMR. spectra of phenalene, phenalenone, of some protonated and alkylated derivatives and the spectra of some substituted phenafulvenes are discussed and very qualitatively correlated with the π-electron distribution in some of these systems.  相似文献   

12.
More than one century ago, Lippmann found that capillary forces can be effectively controlled by external electrostatic forces. As a simple example, by applying a voltage between a conducting liquid droplet and the surface it is sitting on we are able to adjust the wetting angle of the drop. Since Lippmann's findings, electrocapillary phenomena – or electrowetting – have developed into a series of tools for manipulating microdroplets on solid surfaces, or small amounts of liquids in capillaries for microfluidic applications. In this article, we briefly review some recent progress of fundamental understanding of electrowetting and address some still unsolved issues. Specifically, we focus on static and dynamic electrowetting. In static electrowetting, we discuss some basic phenomena found in DC and AC electrowetting, and some theories about the origin of contact angle saturation. In dynamic electrowetting, we introduce some studies about this rather recent area. At last, we address some other capillary phenomena governed by electrostatics and we give an outlook that might stimulate further investigations on electrowetting.  相似文献   

13.
This review addresses recent advances in the field of glassy carbon electrodes film‐modified by acidic functionalities. Attention was posed at the architecture of the functionalizing surface film and at practical applications of the relevant sensors. To facilitate the reading, some summarizing tables were included, each one regarding a certain type of surface modification. A final section is aimed at detailing some remarks emerging from the analysis of the reviewed matter. This allowed highlighting the potentialities of the examined sensors, and evidencing some criticisms about how some of their performances were presented in the relevant papers.  相似文献   

14.
王琳  薛卫东  廖义中 《化学教育》2007,28(10):3-4,7
介绍了纳米材料的一些应用和几种主要纳米材料(如纳米TiO2、碳纳米管、纳米铁粉等)目前已取得的部分生物效应及毒理学的研究结果;讨论了纳米材料对人体和环境带来的潜在影响,及纳米颗粒材料未来的毒性研究重点,并对纳米材料安全性进行了展望。  相似文献   

15.
The quantitative structure-activity relationship (QSAR) of 16 pyrazole compounds was studied by ab initio method at the HF/3-21G level using Guassian03 soft. The optimized structures together with some characteristic and electric parameters of the title compounds were obtained; some stereo-parameters were calculated by HyperChem software. Stepwise multiple regression method was adopted to establish bi-and tri-parametric models between biological activity and some parameters. The lager ΔE and logP,the higher biological activity; and the biological activity would be promoted with the smaller μ,QN and QPYRA. It provided a theory direction to synthesize some compounds with high activity.  相似文献   

16.
The behaviour of Mo and some other elements on Ag MP-1 in alkaline medium was investigated. Equilibrium distribution coefficients, Kd, are presented for Mo on the anion exchangers AG 1-X2, AG 1-X4, AG 1-X8 and AG MP-1, and for some elements on AG MP-1 in alkaline medium. An anion exchange chromatographic separation of Mo from some of these elements is described and some results obtained with this method are reported.  相似文献   

17.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

18.
等离子体引发聚合的机理初探   总被引:5,自引:0,他引:5  
等离子体引发聚合与常规自由基聚合存在许多不同之处。本文从等离子体引发聚合物一些现象,如较强的溶剂效应、极高的单体选择性、主成超高分子量聚合物等方面,系统介绍了等离子体引发聚合的机理研究成果,并提出了自己的看法。  相似文献   

19.
近年来,基于三维图像的人脸识别技术已经取得了很大进展,在约束环境下也能获得很好的识别性能,但仍受限于姿态、表情等因素,需要从算法上改进才能解决其影响。本文分别从基于空域直接匹配、基于局部特征匹配和基于整体特征匹配3个角度出发,对人脸匹配算法以及融合算法进行了研究,列出了部分改进算法的实验结果,并分析了算法有效性的原因,总结了目前面临的三维人脸识别算法难以突破的一些困难及未来的研究趋势。  相似文献   

20.
贾军  赵轶雯  魏寒  沈青 《广州化学》2012,37(3):67-77
综述了微流体技术合成聚合物颗粒的研究进展,包括基于液滴的合成、用流动刻蚀的技术合成及在设备中交替组装成复杂颗粒等合成组装技术,介绍了由此合成的一些不同形状和结构的颗粒及其性能,其中包括具备低密度和特殊表面性能的多孔性颗粒、可以通过加入功能物质制备出的性能优异的复合颗粒、拥有层状结构及多重性能的多功能颗粒、基础的球形颗粒以及通过微流体设备制备的非球形颗粒。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号