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Intra-Cavity Absorption Sensors for gas detection Using Wavelength Sweep Technique

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Journal of Electronic Science and Technology of China 2008年第4期6卷 369-372页

作者： Kun Liu Wen-Cai Jing Gang-Ding Peng Jian-Zhong Zhang Yan Wang Tie-Gen Liu Da-Gong Jia Hong-Xia Zhang Yi-Mo Zhang College of Precision Instrument and Optoelectronics Engineering and the Key Laboratory of Optoeleetronics Information and TechnicalScience Ministry of Education of China Tianjin University Tianjin300072 China School of ElectricalEngineering and Telecommunications University of New South WalesSydney NSW 2052 Australia. Department of Physics Harbin EngineeringUniversity Harbin 150001 China. Tianjin Key Laboratory of Biomedical detection ＆Instruments Tianjin University Tianjin 300072 China.

Wavelength sweep technique （WST） is introduced into intra-cavity fiber laser （ICFL） for low concentration gas detection. The limitation induced by noise can be eliminated using this method, and the performance of the system is improved. The sensitivity of the system is reduced to less than 300 ppm. With WST, sweeping characteristic of the ICFL can be described according to known gas absorption spectra.

关键词： gas detection optical fiber laser,spectrum analysis wavelength measurement.

In-Line gas detection System

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In-Line Gas Detection System

MOF/Polymer-Integrated Multi-Hotspot Mid-Infrared Nanoantennas for Sensitive detection of CO_(2) gas

2010年全国职教通信与信息技术学术年会

作者： Yajing SONG1 Shuping WANG1 Hui WANG2 1Information Engineering Department Shandong Water Polytechnic Rizhao China 2Substations the Design Department Shandong Taikai Transformer Co.Ltd.Tai’an China

This issue developed a gas-line monitoring system,the system consists of upper and lower machine composed of two *** by the computer monitoring software and communication interface component,lower machine by the portable gas detector and communication *** software is implemented on the attendance of Members of gas detection,and the gas concentration and temperature monitoring and alarm,lower machine mainly to complete the gas concentration,temperature,test,and pass the data communication sub-station.

关键词： gas detection communicate microcomputer Visual Basic

来源： cnki会议评论

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cnki会议

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Nano-Micro Letters 2022年第12期14卷 352-372页

作者： Hong Zhou Zhihao Ren Cheng Xu Liangge Xu Chengkuo Lee Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Center for Intelligent Sensors and MEMS(CISM) National University of SingaporeSingapore 117608Singapore NUS Suzhou Research Institute(NUSRI) Suzhou 215123People’s Republic of China

Metal-organic frameworks(MOFs)have been extensively used for gas sorption,storage and separation owing to ultrahigh porosity,exceptional thermal stability,and wide structural ***,when it comes to ultra-low concentration gas detection,technical bottlenecks of MOFs appear due to the poor adsorption capacity at ppm-/ppblevel concentration and the limited sensitivity for signal ***,we present hybrid MOF-polymer physi-chemisorption mechanisms integrated with infrared(IR)nanoantennas for highly selective and ultrasensitive CO_(2) *** improve the adsorption capacity for trace amounts of gas molecules,MOFs are decorated with amino groups to introduce the chemisorption while maintaining the structural integrity for ***,leveraging all major optimization methods,a multi-hotspot strategy is proposed to improve the sensitivity of nanoantennas by enhancing the near field and engineering the radiative and absorptive *** a benefit,we demonstrate the competitive advantages of our strategy against the state-of-the-art miniaturized IR CO_(2) sensors,including low detection limit,high sensitivity(0.18%/ppm),excellent reversibility(variation within 2%),and high selectivity(against C_(2)H_(5)OH,CH_(3)OH,N_(2)).This work provides valuable insights into the integration of advanced porous materials and nanophotonic devices,which can be further adopted in ultra-low concentration gas monitoring in industry and environmental applications.

关键词： Metal-organic framework gas detection Mid-infrared nanoantennas Multi-hotspot Loss engineering

A risk-based methodology for the optimal placement of hazardous gas detectors

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1078-1086页

作者： Kang Cen Ting Yao Qingsheng Wang Shengyong Xiong School of Civil Engineering and Architecture Southwest Petroleum University Chengdu 610500 China Department of Fire Protection & Safety and Department of Chemical Engineering Oklahoma State University Stillwater OK 74078 USA Wanzhou Branch Plant of Chongqing General Natural gas Purification Plant Southwest Oil & Gasfield Company PetroChina Wanzhou Chongqing 404001 China

Hazardous gas detection systems play an important role in preventing catastrophic gas-related accidents in process industries. Even though effective detection technology currently exists for hazardous gas releases and a majority of process installations have a large number of sensitive detectors in place, the actual operating performance of gas detection systems still does not meet the expected requirements. In this paper, a riskbased methodology is proposed to optimize the placement of hazardous gas detectors. The methodology includes three main steps, namely, the establishment of representative leak scenarios, computational fluid dynamics(CFD)-based gas dispersion modeling, and the establishment of an optimized solution. Based on the combination of gas leak probability and joint distribution probability of wind velocity and wind direction, a quantitative filtering approach is presented to select representative leak scenarios from all potential scenarios. The commercial code ANSYS-FLUENT is used to estimate the consequence of hazardous gas dispersions under various leak and environmental conditions. A stochastic mixed-integer linear programming formulation with the objective of minimizing the total leak risk across all representative leak scenarios is proposed, and the greedy dropping heuristic algorithm(GDHA) is used to solve the optimization model. Finally, a practical application of the methodology is performed to validate its effectiveness for the optimal design of a gas detector system in a high-sulfur natural gas purification plant in Chongqing, China. The results show that an appropriate number of gas detectors with optimal cost-effectiveness can be obtained, and the total leak risk across all potential scenarios can be substantially reduced. This methodology provides an effective approach to guide the optimal placement of pointtype gas detection systems involved with either single or mixed gas releases.

关键词： Leak scenario Leak risk gas detection Detector placement Mixed-integer linear programming

Broad gain,continuous-wave operation of InP-based quantum cascade laser atλ~11.8μm

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Chinese Physics B 2021年第12期30卷 413-417页

作者： Huan Wang Jin-Chuan Zhang Feng-Min Cheng Zeng-Hui Gu Ning Zhuo Shen-Qiang Zhai Feng-Qi Liu Jun-Qi Liu Shu-Man Liu Zhan-Guo Wang Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Academy of Quantum Information Sciences Beijing 100193China

We demonstrate a broad gain,continuous-wave(CW)operation InP-based quantum cascade laser(QCL)emitting at 11.8μm with a modified dual-upper-state(DAU)and diagonal transition active region design.A 3 mm cavity length,16.5μm average ridge wide QCL with high-reflection(HR)coatings demonstrates a maximum peak power of 1.07 W at 283 K and CW output power of 60 m W at 293 *** device also shows a broad and dual-frequency lasing spectrum in pulsed mode and a maximum average power of 258.6 mW at 283 ***,the full width at half maximum(FWHM)of the electroluminescent spectrum measured at subthreshold current is 2.37μm,which indicates a broad gain spectrum of the *** tuning range of 1.38μm is obtained by a grating-coupled external cavity(EC)Littrow configuration,which is beneficial for gas detection.

关键词： dual-upper-state(DAU) quantum cascade lasers external cavity gas detection

The development and application of dual-comb spectroscopy in analytical chemistry

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Chinese Chemical Letters 2023年第1期34卷 39-44页

作者： Ziheng Wei Xinyi Ren Ming Yan Hulie Zeng Department of Pharmaceutical Analysis School of PharmacyFudan UniversityShanghai 201203China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China

Analytical chemistry plays an important role in the qualitive and quantitative analysis for molecules in the various circumstances,especially for the high-resolution *** dual-comb spectroscopy(DCS)technology with the characteristics of high resolution,high sensitivity and instantaneous sampling exhibited a great potential in high-resolution in-situ spectral methods and has been active in the fields of spatial ranging,air composition analysis,reaction monitoring and so *** this review,we will summarize the principle of DCS according to the different wavelength coverage and overview the applications of DCS in analytical chemistry.

关键词： Dual-comb spectroscopy Infrared spectrum Raman spectrum Spectral analysis gas detection

Preparation of homogeneous porous Zn-CoOx and its response to alcohols under relative low operating temperature

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Chinese Chemical Letters 2020年第8期31卷 2059-2062页

作者： Xiao Zhang Yaohua Xu Hao Liu Wenrui Zhao Anjie Ming Feng Wei State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China GRIM AT Engineering Institute Co. Ltd.Beijing 101407China

A homogeneous porous Co3 O4-ZnO nanomaterial(Zn-CoOx)was successfully fabricated by precipitationannealing *** as-prepared Zn-CoOx exhibited good response,reliable reversibility and good selectivity towards alcohols,which attributed to the porous structure and p-n heterojunction formed between Co3 O4 and *** particular,the different Fermi levels of Co3 O4 and ZnO leaded to a further increase the depth of the space charge layer,which improved the gas sensitivity of the material from 10%to 480%.Besides,the continuous CO3 O4 leaded to a relatively lower operating temperature and resista *** material preparation method and bimetallic oxides could be widely used in the research and development of metal oxide gas sensitive materials and sensors.

关键词： Co3O4 ZnO P-N heterojunction Alcohol gas detection

Potential of eNose Technology for Monitoring Biological CO_(2) Conversion Processes

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Transactions of Tianjin University 2024年第5期30卷 381-394页

作者： Muhammad Awais Syed Muhammad Zaigham Abbas Naqvi Sami Ullah Khan MIjaz Khan Sherzod Abdullaev Junfeng Wu Wei Zhang Jiandong Hu Department of Electrical Engineering Henan Agricultural UniversityZhengzhou 450002China Henan International Joint Laboratory of Laser Technology in Agriculture Sciences Zhengzhou 450002China State Key Laboratory of Wheat and Maize Crop Science Zhengzhou 450002China Department of Mathematics Namal UniversityTalagang RoadMianwali 42250Pakistan Department of Mechanical Engineering Prince Mohammad Bin Fahd University31952 Al-KhobarKingdom of Saudi Arabia Faculty of Chemical Engineering New Uzbekistan UniversityTashkentUzbekistan Scientific and Innovation Department Tashkent State Pedagogical UniversityTashkentUzbekistan

Electronic nose(eNose) is a modern bioelectronic sensor for monitoring biological processes that convert CO_(2) into valueadded products, such as products formed during photosynthesis and microbial fermentation. eNose technology uses an array of sensors to detect and quantify gases, including CO_(2), in the air. This study briefly introduces the concept of eNose technology and potential applications thereof in monitoring CO_(2) conversion processes. It also provides background information on biological CO_(2) conversion processes. Furthermore, the working principles of eNose technology vis-à-vis gas detection are discussed along with its advantages and limitations versus traditional monitoring methods. This study also provides case studies that have used this technology for monitoring biological CO_(2) conversion processes. eNose-predicted measurements were observed to be completely aligned with biological parameters for R~2 values of 0.864, 0.808, 0.802, and 0.948. We test eNose technology in a variety of biological settings, such as algae farms or bioreactors, to determine its effectiveness in monitoring CO_(2) conversion processes. We also explore the potential benefits of employing this technology vis-à-vis monitoring biological CO_(2) conversion processes, such as increased reaction efficiency and reduced costs versus traditional monitoring methods. Moreover, future directions and challenges of using this technology in CO_(2) capture and conversion have been discussed. Overall, we believe this study would contribute to developing new and innovative methods for monitoring biological CO_(2) conversion processes and mitigating climate change.

关键词： Electronic nose(eNose) CO_(2) conversion Biological monitoring gas detection Bioelectronic nose

Recent Progress of Fiber Sensing Technologies in Tianjin University

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Photonic Sensors 2011年第1期1卷 90-96页

作者： Tiegen LIU Kun LIU Junfeng JIANG Enbang LI Hongxia ZHANG Dagong JIA Yimo ZHANG Key Laboratory of Opto-electronics Information and Technical Science College of Precision Instrument&Opto-electronics EngineeringTianjin UniversityTianjin 300072China

The up to date progress of fiber sensing technologies in Tianjin University are proposed in this ***-optic temperature sensor based on the interference of selective higher-order modes in circular optical fiber is *** demodulation for extrinsic Fabry-Perot interferometer(EFPI)and fiber Bragg grating(FBG)sensors is realized based on white light *** concentration detection is realized based on intra-cavity fiber laser *** maintaining fiber(PMF)is used for distributed position or displacement *** on the before work and results,we gained National Basic Research Program of China on optical fiber sensing technology and will develop further investigation in this area.

关键词： Fiber sensing high temperature parallel demodulation gas detection distributed sensing