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排序方式: 共有249条查询结果,搜索用时 15 毫秒
1.
选取某地330 MW煤粉炉(PC炉)和350 MW循环流化床锅炉(CFB)的燃煤电厂进行汞排放特性的研究。采用30B法和安大略法对两个燃煤电厂的除尘器入口、除尘器出口、脱硫塔出口和湿式电除尘器出口的烟气进行了取样和汞浓度分析,采集了入炉煤和副产物底渣、飞灰及脱硫石膏样品。通过样品中汞含量的分布,探讨了PC炉与CFB锅炉机组现有污染物控制设备对汞的协同脱除作用。结果表明,350 MW CFB电厂除尘器出口烟气平均汞浓度降低至0.43μg/m~3,布袋除尘器对汞的捕获效率达到98.9%,相应的燃烧副产物中飞灰是汞的主要富集对象。对于330 MW PC炉电厂,除尘器入口和除尘器出口烟气汞浓度均高于350 MW CFB电厂,烟气汞浓度从除尘器入口、除尘器出口到脱硫塔出口依次降低,在脱硫塔出口烟气汞浓度降低至0.42μg/m~3,静电除尘器和湿式脱硫塔对烟气汞的捕获效率分别为75.0%和22.4%,相应的产物中飞灰和脱硫石膏中汞都有一定程度的富集。  相似文献   
2.
为了能够对某型号无人机雪橇式减震器的最大静载荷试验进行实时检测和保存数据,设计了一种基于STM32F103ZET6单片机的雪橇式减震器检测设备。设备利用压力传感器和光栅尺分别完成减震器在压缩过程中,对静载荷与压缩距离的采集并转换为数字信号,信号在减震器压缩过程中的特定位置被采集,将采集到的信号通过无线模块上传至上位机;以C#平台开发的上位机作为收集、处理下位机传入的静载荷、压缩距离的信号,最后借助图形用户接口控件实现静载荷、压缩距离的曲线显示,将采集到的数据使用SQL数据库实现保存,以便于操作管理员读取和历史查询。测试结果表明:雪橇式减震器检测装置可以完成对减震器的自动化检测。  相似文献   
3.
基于LCD显示器光谱特性的图像颜色一致性研究   总被引:2,自引:0,他引:2  
为了解决环境光和显示器色温对LCD显示器图像颜色再现有较大影响的问题,提出一种基于LCD显示器光谱特性的图像颜色一致性方法。通过测量在不同环境光和色温下99个行业认可颜色的光谱,总结出不同环境光和色温对LCD显示器图像颜色再现的光谱规律。利用不同环境光下的光谱叠加性及不同色温下的光谱对应规律,实现了不同环境光和色温下的LCD显示器图像颜色一致性,一致性后的图像平均主观评价Z得分为0.50。研究结果表明,该方法能够很好地解决不同环境光和色温下的LCD显示器图像颜色的一致性问题。  相似文献   
4.
冯辉荣 《力学与实践》2012,34(6):46-49,87
考虑实际坡度条件下, 提出了基于压力传感器的汽车重心与安全车速实时监测系统的多元力学模型. 建立了考虑车辆重心高度、路面纵横双向坡度及路面半径等因素的车辆安全车速控制力学模型, 并在三维模型分析的基础上提出监测与报警机理, 可为汽车安全系统提供安全车速与重心计算的多维力学模型, 为研制汽车安全车速实时监测系统提供了必要参数与依据.  相似文献   
5.
During the last 20 years, beamline BL08B has been upgraded step by step from a photon beam‐position monitor (BPM) to a testing beamline and a single‐grating beamline that enables experiments to record X‐ray photo‐emission spectra (XPS) and X‐ray absorption spectra (XAS) for research in solar physics, organic semiconductor materials and spinel oxides, with soft X‐ray photon energies in the range 300–1000 eV. Demands for photon energy to extend to the extreme ultraviolet region for applications in nano‐fabrication and topological thin films are increasing. The basic spherical‐grating monochromator beamline was again upgraded by adding a second grating that delivers photons of energy from 80 to 420 eV. Four end‐stations were designed for experiments with XPS, XAS, interstellar photoprocess systems (IPS) and extreme‐ultraviolet lithography (EUVL) in the scheduled beam time. The data from these experiments show a large count rate in core levels probed and excellent statistics on background normalization in the L‐edge adsorption spectrum.  相似文献   
6.
为了实现漆包机生产的远程监控,设计了一款基于Web的实时漆包机远程监控平台。该平台使用模块化,可扩展的设计方案,采用了Spring MVC的后台Web应用程序框架,基于Modbus协议的数据交互,Ajax方式的网络数据异步提交以及无刷新的图表显示技术。传统的监控平台只能通过以太网在企业内部访问,而该平台可接入互联网,可实现随时随地通过电脑及或者移动终端对生产设备各部分的温度点、电机风机转速、耗电量统计的实时监视,对温度的上下限及电机转速进行远程控制,接收设备状态异常的实时报警,数据存储分析。实验测试表明,该平台的实时性和稳定性均能达到车间生产的要求。  相似文献   
7.
Design and construction of the first prototype ionization chamber for CSNS and Proton Accelerator (PA) beam loss monitor (BLM) system is reported. The low leakage current (<0.1 pA), good plateau (≈800 V) and linearity range up to 200 Roentgen/h axe obtained in the first prototype. All of these give us good experience for further improving the ionization chamber construction.  相似文献   
8.
A cosmic-ray muon telescope has been collecting data since the end of 2014, which was shortly after the telescope was built in the Zhongshan Station of Antarctica. The telescope is the first observation device to be built by Chinese scientists in Antarctica. The pressure change is very strong in Zhongshan station. The count rate of the pressure correction results shows that the large variations in the count rate are likely caused by pressure fluctuations. During the period from 18 June to 22 June 2015, four halo coronal mass ejections(CMEs) were ejected from the Sun. These CMEs initiated a series of Forbush decreases(FD) when they reached the Earth. We conducted a comprehensive study of the intensity fluctuations of galactic cosmic rays recorded during FDs. The intensity fluctuations used in this study were collected by cosmic ray detectors of multiple stations(Zhongshan, McMurdo,South Polar, and Nagoya), and the solar wind measurements were collected by ACE and WIND. The profile of the FD of 22 June demonstrated a four-step decrease. The traditional one-or two-step FD classification method does not adequately explain the FD profile results. The interaction between the faster CME that occurred on 21 June 2015 and the two slow CMEs of the earlier few days should be considered. The cosmic ray intensities of the South Pole,McMurdo, and Zhongshan stations have similar hourly variations, whereas the galactic cosmic rays recorded between polar and non-polar locations are distinct. The FD pre-increase of 22 June 2015 for the Nagoya muon telescope(non-polar location) lags those of the McMurdo and Zhongshan stations(polar locations) by 1 h. The FD onset of22 June 2015 for the Nagoya muon telescope lags those of the polar locations by 1 h.  相似文献   
9.
Previously calibrated passive detectors (CR-39) and an active radon device (Radon Monitor RM3) were used to study seasonal variation of radon-222 concentration levels inside and outside specific locations in Jordan. The study sites were located in an area that used to be an old phosphate mine. We found that the maximum value of radon concentration in air inside the dwellings, as measured by the passive dosimeters, was 1532.9 Bq/m3 during the winter season, and the minimum one was 46.3 Bq/m3 during fall season. While the highest and lowest readings of the active monitor were 892 and 4 Bq/m3 during fall and summer seasons, respectively. The radon concentration in soil ranges from 0.2 kBq/m3 in spring to 37.8 kBq/m3 in fall.  相似文献   
10.
Geothermal waters have been used on a large scale for bathing, drinking and medical purposes, while the consumption of bottled mineral waters is increasing. In this work, radon and radium activity concentrations of thermal and bottled mineral waters, originating from different regions of Hungary, were studied by different radioanalytical methods. It was found that the thermal springs, which supply the world famous baths of Budapest along the right riverside of the Danube, have high 222Rn and 226Ra activity concentration: up to about 100 and 1 kBqm−3, respectively. The radium content of some investigated geothermal waters found in the NE region of the Great Hungarian Plain is even higher: up to several kBqm−3. The 226Ra content of bottled mineral waters, commercially available in Hungary, was determined by gamma-spectrometric method, applying radiochemical separation. The highest value exceeded 2 kBqm−3 in the case of the Apenta mineral water, which is a popular brand in Hungary, as well as in Europe and North America.  相似文献   
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