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排序方式: 共有26条查询结果,搜索用时 15 毫秒
1.
 介绍一种储存环束流位置监测系统的标定装置。这套标定装置是为NSRL二期工程储存环注入段真空盒改造而研制的。系统的标定精度达±0.01mm。该装置已用于新增注入段真空管的束流位置探测器的定标,获得了探头定标值,并根据其拟合和计算结果对注入段真空管进行了筛选,被选中的真空管已装入储存环注入段。  相似文献   
2.
杨国成 《光子学报》1995,24(6):556-559
味精精制过程中的谷氨酸钠溶液浓度需控制在一定的范围。本文报道一种可用于在线监测谷氨酸钠浓度的双光束激光旋光差动式检测法,并对该方法的可行性进行了初步的实验研究。实测结果表明本方法有较好的实用性。  相似文献   
3.
HL-2A is the first divertor tokamak in China. The vacuum system is one of the important parts of the HL-2A tokamak, which has to be work well during the physics campaign in 2004. As the tokamak machine is separated from the operation staff during discharges, to guarantee the safe and reliable operation of the vacuum system, it is necessary to watch the vacuum system outside the machine hall with an automatic monitoring system. The paper describes the design and manufacture of the monitoring system.  相似文献   
4.
采用紫外-可见吸收光谱法现场监测了苯胺电化学聚合时的动力学降解过程,简单、直观地显示了阳极电位、酸度和苯胺浓度对降解过程的影响,结果表明,阳极电位越正、酸度越强、苯胺浓度越大,聚苯胺的降解速度越快。该方法得到的结果与聚苯胺膜在空白溶液中采用循环伏安法研究其降解动力学时得到的结果类似。  相似文献   
5.
大型边坡监测系统数据庞大,项目及测点繁多。传统的数据库管理系统很难直观地查询分析监测数据。作者用在Window 系统下面向对象的程序设计语言VisualBasic和面向对象的数据库管理开发系统Access 开发了具有可视化查询分析特征的监测信息分析管理系统。本文以五强溪水电站左岸船闸边坡为例,介绍了系统的设计和程序功能。  相似文献   
6.
A new application of intact cell MALDI-TOF MS (ICM-MS) methodology is described for monitoring the production of viral proteins and viral like particles using the baculovirus/insect cells expression system. Various MALDI matrices, cell preparation methods, cell/matrix volume ratio and MALDI target application procedures were tested in order to obtain the highest intensity and reproducibility of intact insect cell spectra. The web interface, SPECLUST (http://bioinfo.thep.lu.se/speclust.html), was used to construct dendograms based on MALDI-TOF MS data for evaluation of fingerprint changes.We demonstrate that insect cell mass spectrum fingerprints are characteristic of each viral protein/particle production. Their changes along the time for each production experiment correlate with the intracellular viral protein content determined by Western blot.This work shows that this simple, fast and low cost assay, which requires low sample volume, is a powerful analytical tool that complements the most common analytical methods used for monitoring bioprocesses and has potential application in the biotechnological industry namely, in the production of recombinant proteins.  相似文献   
7.
藻类水华爆发已成为影响内陆水体生态环境的重要因素。遥感能够提供实时的大范围观测,在水华监测中起到越来越重要的作用。遥感植被指数已广泛应用于藻类水华监测中,通过对研究区植被指数图像进行阈值分割,能够反映不同子区域内的藻类爆发程度;然而阈值分割法的结果只能反映某一时间点(图像获取时)的藻类爆发状况,无法表征长时间内藻类的变化。相比于单个时间点的植被指数,植被指数时间谱(时谱)包含藻类的物候信息,能够更加全面准确地反映藻类的长时间变化。目前,植被指数时间谱还尚未应用到水华相关研究中。选取2001年—2013年太湖区域的MODIS NDVI数据,构建年度NDVI时谱数据,利用(support vector machine, SVM)方法对每年的太湖蓝藻水华爆发强度进行分类,将太湖重度、中度和轻度蓝藻水华爆发的区域以及水生植物的区域提取出来,得到其空间分布和面积;并从2007年的时谱数据中抽取了8个时间点的NDVI图像,利用传统阈值分割法提取太湖重度、中度和轻度蓝藻水华爆发的区域,将结果与2007年时谱数据分类的结果进行对比。结果表明:所提出的方法能够更加全面准确地对太湖蓝藻爆发强度进行分类,通过NDVI时谱曲线提供的丰富物候信息可准确区分蓝藻与水生植被区域。本研究有望为准确掌握和预测藻类水华的爆发趋势及强度提供有效手段。  相似文献   
8.
Abstract

Todays progress in chemical and allied industries as well as the product development leading to such progress depend upon the successful mastering of environmental and safety and health problems. There is a challenging need for the identification and quantification of hazardous substances in the air and water at concentrations in the ppm, ppb and often ppt range or below that value. A continuous surveillance is best achieved by automated monitor devices, responding to specific chemicals of choice. In our Department of Analytical Research we have been developing surveillance monitor systems for several years and we accumulated experience in the field of ambient air and waste water control. Our instrumental concept was to construct an easily controlled mobile instrument, distinguished by its high sensitivity and specificity for trace and ultratrace substances, and its versatility and sturdiness in field measurements. The monitor systems represent integrated analysis systems in which standardization and calibration procedures, trace enrichment steps and gas chromatographic separations are linked together on-line thus permitting a continuous, automated operation. Conventional as well as unconventional detectors, such as a mass spectrometer may be coupled with the separation step, The monitor systems are designed to perform survey analyses at a rate of one to ten analyses per hour on the hour and may be equipped with an acoustic or optical warning device, indicating the moment when a specific substance surpasses a certain critical concentration limit. The paper describes three types of instrument designs, distinguished by their degree of sophistication, i.e. the detection limit on one side and the different media in which it operates on the other  相似文献   
9.
全宇 《应用声学》2017,25(7):94-97
近年来,全球互联网技术飞速发展,网络技术广泛应用于各个领域。随着网络技术的快速发展,我国各大高校开设计算机实验室,在高校范围内搭建的小型局域网中引入监控系统,辅助高校实验室的日常使用管理工作。传统的监控系统在小型局域网中存在数据资源交互消耗大、数据传输延迟高、视频数据储存空间利用率低等问题,给计算机实验室的日常管理带来不便。针对上述问题,提出小型局域网下高校计算机实验室监控系统设计。对数据交互过程中资源消耗大的问题,采用双协议传输单元进行资源交互算法的改进;对传统监控系统存在的数据传输延迟问题,采用数据阵列重组模组进行数据内部优化处理;采用ViodTM视频压缩单元,对监控视频进行算法核心压缩处理,从问题产生根源进行解决。通过实验证明,提出的小型局域网下高校计算机实验室监控系统设计,具有资源占用小、传输速度快、视频存储率高等特点。  相似文献   
10.
Oxidative burst is the rapid and transient production of large amounts of reactive oxygen species, including superoxide anion, hydrogen peroxide (H2O2), and hydroxyl radical. A rapid and simple technique was employed for in vivo detection of oxidative burst in oilseed rape (Brassica napus L.) leaves, using a modified electrode. Platinum (Pt) micro-particles were dispersed on a Pt electrode, coated with a poly (o-phenylenediamine) film. This exhibited high sensitivity, selectivity and stability in H2O2 detection. Amperometry was used to obtain satisfactory linear relationships between reductive current intensities and H2O2 concentrations at −0.1 V potential in different electrolytes. This electrode was used in vivo to detect oxidative burst in oilseed rape following fungal infection. Oxidative bursts induced by infection of the fungal pathogen Sclerotinia sclerotiorum (Lib.) de Bary exhibited notably different mechanisms between a susceptible and a resistant glucose oxidase-transgenic genotype.  相似文献   
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