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Application of a Self-developed Proton Transfer Reaction-Mass Spectrometer to on-line monitoring Trace Volatile Organic Compounds in Ambient Air

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Chemical Research in Chinese Universities 2016年第4期32卷 565-569页

作者： KANG Meng ZOU Xue LU Yan WANG Hongmei SHEN Chengyin JIANG Haihe CHU Yannan Center of Medical Physics and Technology Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 P R. China Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 P. R. China

Real-time and on-line monitoring volatile organic compounds（VOCs） are valuable for real-time evalua- ting air quality and monitoring the key source of pollution. A self-developed proton transfer reaction-mass spectro- meter（PTR-MS） was constructed and applied to on-line monitoring trace VOCs in ambient air in Hefei, China. With the help of a self-developed catalytic converter, the background signal of the instrument was detected and the stability of the instrument was evaluated. The relative standard deviation of signal at m/z 21 was only 0.74% and the detection limit of PTR-MS was 97 part per trillion（97x 10-12, volume ratio）. As a case of the air monitoring in Hefei, the am- bient air at Dongpu reservoir spot was on-line monitored for 13 d with our self-developed PTR-MS. Meanwhile, a solid-phase micro-extraction（SPME） technique coupled to gas chromatography-mass spectrometry/mass spectrometry （GC-MS/MS） was also used for the off-line detection of the air. The results show that our self-developed PTR-MS can be used for the on-line and long-term monitoring of VOCs in air at part per trillion level, and the change trend of VOCs concentration monitored with PTR-MS was consistent with that detected with the conventional SPME-GC-MS. This self-developed PTR-MS can fully satisfy the requirements of air quality monitoring and real-time monitoring of the key pollution sources.

关键词： Proton transfer reaction-mass spectrometry Volatile organic compound(VOC) on-line monitoring

on-line monitoring method for electrode invalidation during spot welding of zinc coated steel

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On-line monitoring method for electrode invalidation during ...

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Dong-Sheng Mei1 a Dong-Qing Li1b Zhong-Dian Zhang1c Ling Lan1 1. State key laboratory of advanced welding production technology harbin institute of technology 150001 china

In the process of spot welding of zinc coated steel, because of the existence of zinc coat, the electrode invalidation is accelerated greatly, the electrode invalidation causes unacceptable welding quality. A collecting system is developed with a C8051F020 microcomputer as the controlling core, the whole variety trend of such parameters as welding current, supply voltage and dynamic resistance etc are obtained through the comprehensive processing towards the data collected. An on-line monitoring method is given through the relationship between electrode wear and welding parameters, which is valuable for the industrial production.

关键词： dynamic resistance on-line monitoring electrode invalidation

on-line monitoring System of Ultra-high-frequency PD in Transformer Based on Virtual Instrument

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On-line Monitoring System of Ultra-high-frequency PD in Tran...

2007 8th International Conference on Electronic Measurement & Instruments（ICEMI’2007）

作者： Liu Yunpeng 1 2 Wang Juan 1 Lv Fangcheng 1 Jiang Qingyun 3 (1. North China Electric Power University Baoding 071003 China) (2. Wuhan High Voltage Research Institute of SGCC Hongshan District Wuhan 430074 China) (3. Xiamen Extrahigh Voltage Company Xiamen 361012 China)

An on-line monitoring system of ultra-high-frequency （UHF） PD was investigated for transformers in this paper. Based on envelope detection technique, the measure principle of UHF PD signals was analyzed, and the hardware of this system was developed. The software of this system, consisting of data acquisition data storage signal display and graph analysis, was constructed using National Instruments’ Measurement Studio software. The PD of five discharge models was measured. Experimental results show that this system has wider band width, stronger ability of interference suppression, and higher stability, and can be useful for on-line monitoring of UHF PD in transformers.

关键词： transformer partial discharge(PD) ultra-high-frequency(UHF) on-line monitoring Virtual Instrument

Design of on-line monitoring System for UHVDC Earth Electrode

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Journal of Power and Energy Engineering 2016年第2期4卷 13-18页

作者： Pinghao Ni Wei Wang Peng Wei School of Electrical Engineering Beijing Jiaotong University Beijing China Ningxia Electric Power Maintenance Company Ningxia China

At present the detecting of ultra high voltage direct current (UHVDC) earth electrode frequently uses manual inspection. This method can't get the real-time operational data of the earth electrodes, and meanwhile, the labor cost is very high. In order to satisfy the security needs of UHVDC, this paper designs an on-line monitoring system for UHVDC earth electrode. By 3G wireless communication-technologies, the system can monitor remotely many kinds of data such as the value of the grounding current, water level of the observation well, soil temperature and humidity near the earth electrode, the micro-climate around the earth electrode site, video data, etc. Through analyzing the datum, the system has broad prospect on fault detection and life evaluation of the UHVDC earth electrode.

关键词： UHVDC Earth Electrode on-line monitoring 3G

Analysis and Application of the Synthetic Relative Measuring Method in on-line monitoring for Capacitive Equipment in Power Systems

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Journal of Electronic Science and Technology 2011年第3期9卷 270-277页

作者： Qing Guo Li-Jun Qin Hua-Wei Jin Department of Electricaland Electronic Engineering North China Electric Power UniversityBeijing 102206 China

On-line measurement for dielectric loss angle can effectively monitor the insulation condition of capacitive equipment in power systems. Synthetic relative measuring methods not only markedly overcome the shortcomings of traditional absolute measuring methods but also greatly improve the accuracy of dielectric loss angle measurement. However, synthetic relative measuring methods based on two or three pieces of capacitive equipment do not have the characteristic of generality. In this paper, a principle of synthetic relative measuring method is presented. The example of application for synthetic relative methods based on three and four pieces of capacitive equipment running in the same phase is taken to present the failure judgment matrices for N pieces of equipment. According to these matrices, the fault condition of N pieces of capacitive equipment can be watched, which is more general. Then some problems needing to be concerned along with two diagnostic methods used in diagnostic system are introduced. Finally, two programmable flow charts for the two methods are given and corresponding examples demonstrate their feasibility in practice.

关键词： Index Terms-Capacitive equipment dielectric loss angle on-line monitoring synthetic relative measuring method failure judgment matrix.

Design of Na-K Alloy Differential Pressure Sensor with on-line monitoring Function

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International Journal of Plant Engineering and Management 2018年第3期23卷 129-133页

作者： WU Linghui XU Dong The 49th Research Institute China Electronics Technology Group Corporation

Because the melting point of the alkalis is very high and the metal activity is strong, the common pressure sensor can＇t be used to measure pressure of liquid metal. In this paper, a differential transformer differential pressure sensor for measuring liquid alkalis pressure is designed, the working principle and specific design plan of the sensor are introduced, the standard current signal （ 4 -20 mA） or digital communication RS485 can be output according to the needs, and the functions of remote monitoring and data optimization can be realized through the LAN interface.

关键词： bellows differential pressure sensor spring mechanism high temperature on-line monitoring

on-line monitoring of Cutting Tool Fracture & Wear

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Journal of Beijing Institute of Technology 1992年第2期1卷 139-150页

作者：王信义肖定国宋新民北京理工大学机械工程系北京100081

A technique of detecting cutting tool fracture and ultimate wear by si- multaneously monitoring both the spindle motor current and cutting process related acoustic emission(AE)in the cutting process is *** technique can detect breakage of drills having diameter over 0.8mm,turning cutter crack of area over 0.2mm,and the ultimate *** principle,system construction,experimental method and result of the technique are *** ratio of success in detection approaches 96% or higher.

关键词： on-line monitoring acoustic emission/tool fracture motor current

New Method for Inking-up on-line monitoring with Ultrasonic Sensor

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New Method for Inking-up On-line Monitoring with Ultrasonic ...

2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies

作者： Jiwen Lu Erhu Zhang Yajun Chen Department of Information Science Xi’an University of Technology Xi’an 710048 China

＜正＞In the procedure of printing progress epically for multicolor printing, better ink controlling is very necessary and important to obtain high printing quality products and presswork and it is very crucial to monitor the ink on-line in the printing procedure. Automatic printing inking-up has become one important research topic in the field of printing industrial production and automatic control. This paper presents a method for monitoring and controlling the printing ink in the press ink fountain automatically using one controlled system based on ultrasonic sensor. Firstly, physical properties and the installation location of the ultrasonic sensor is explained and analyzed and one monitoring system consists of ultrasonic emitter, ultrasonic acceptor, voltage-magnified circuit, detecting circuit and alarming circuit is designed;then an improved on-line monitoring method is put forward and a system which can give alarm to add the printing ink while the ink in the ink fountain reaches the minimum position is developed. Lastly, the quantity of ink in the ink fountain can be displayed on-line and the new system using on-line monitoring method can realize the automation of inking-up in printing process. Experimental results in our laboratory show that this on-line monitor method can improve the automatic degree of most presses in our country, which will bring great economical and commercial benefits to our country’s printing industry.

关键词： on-line monitoring ultrasonic sensor automatic control inking-up printing industry

Design and Implementation of Water Quality on-line monitoring System Based on Combination of Multiple Data Transmission

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Design and Implementation of Water Quality On-line Monitorin...

2014 International Conference on Green Materials and Environmental Engineering (GMEE2014)

作者： Jin-dong Yu He Huang Guang-rong Chen GuangDong Construction Vocational Technology Institute

ISBN: (纸本)9783038353201

Water quality on-line monitoring is the necessary means to control water environment pollution and provide effective data for the research of water ecological restoration. Using free wireless communicating module of Zig Bee we realized transmitting data from sensors on the river bank to the data storage center. Based on serial ports of micro-controller a protocol converter circuit was designed. With program the Modbus RTU protocol data packet on RS-485 bus was converted into Zig Bee communication protocol and then transmitted to the Internet. Supplemented by GSM the reliability of data was enhanced. Water quality online monitoring system based on multiple data communication provides browse of real-time river water quality through the Internet network, which is fast and convenient to be exported for research.

关键词： on-line monitoring Data transmission Modbus RTU protocol ZigBee network B/S