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Field observation of air-sea CO_(2) and H2O flux using the eddy covariance method based on 100 Hz gas analyzer in the Bohai and Yellow Seas
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作者 Tan Yu Yuhan Xia +8 位作者 Zhengli Qiu Bangyi Tao Yan Bai Xianqiang He Bing Chen Mingxing Li Yu Wang Qilan Zhang Chao Liang 《Acta Oceanologica Sinica》 2025年第7期161-176,共16页
Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The ... Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The observations were corrected by employing wild point rejection,linear detrending,delay correction,coordinate rotation,time matching,and Webb,Pearman,and Leuning(WPL)correction.The results of spectral analysis and a turbulence development adequacy data quality check showed that the overall observation data quality was good.The air-sea water vapor and CO_(2) flux results showed that the observation duration affected both the air-sea flux intensity and direction at different observation frequencies.At shorter observation durations,the air-sea flux values measured at 100 Hz were smaller than the 20 Hz measurements and had opposite directions.In addition,the WPL correction reduced the overall air-sea flux and partially minimized the effect of observation frequency on the air-sea flux intensity.These results showed that high-frequency observations showed more turbulence variations than low-frequency observations.This conclusion could promote an understanding of small-scale turbulence variations. 展开更多
关键词 eddy correlation method 100 Hz gas analyzer TDLAS air-sea flux observation frequency
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Measurement of Carbon Dioxide and Sulfur Dioxide in Soil Gases as a Guide to Mineral Exploration under Exotic Overburden
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作者 WAN Wei FAN Huihu +3 位作者 CHU Kelei CHENG Zhizhong WANG Mingqi ZUO Libo 《Acta Geologica Sinica(English Edition)》 2025年第5期1494-1508,共15页
Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetra... Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetrability and vertical migration.The previous rapid gas analyzer cannot determine low concentrations of soil gases because of inadequate sensitivity,therefore,it is necessary to develop a more sensitive analytical technique.In this paper,the pilot studies on CO_(2) and SO_(2) geochemical measurements were performed at the Zhuxi W-(Cu)deposit,Jiapigou gold ore-concentrated area,and Tukuzbay gold deposit.This study employed rapid gas analyzer based on Infrared Absorption Spectroscopy and Electrochemical Analysis,which can detect low concentrations of CO_(2) and SO_(2) and greatly improve the reliability of test data.The results show that CO_(2) and SO_(2) show clear anomalies over deeply concealed ore bodies and faults,demonstrating that CO_(2) and SO_(2) anomalies can reveal indicative information about concealed mineralization and faults.Moreover,CO_(2) and SO_(2) anomalies can identify mineralization information exceeding 1,000 m in depth,suggesting that this method has large detection depth.Therefore,CO_(2) and SO_(2) geochemical measurement method is a feasible tool to discern deeply concealed mineralization and faults,and can provide a new idea in prospecting for concealed ore deposits in covered areas. 展开更多
关键词 gas measurement concealed deposit carbon dioxide sulfur dioxide rapid gas analyzer
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Enhanced Ion Sampling Techniques for In-situ Neutral Gas and Low-energy Ions Exploration of Main-belt Comet
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作者 WANG Xinyue ZHANG Aibing +4 位作者 SU Bin DU Dan KONG Linggao TIAN Zheng ZHENG Xiangzhi 《空间科学学报》 北大核心 2025年第3期749-760,共12页
One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object... One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water. 展开更多
关键词 neutral gas low energy ions sampling techniques ion sampling techniques investigate space environment main belt comet gas ion analyzer gia situ measurement
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Surface Modification of Polyethylene Terephthalate(PET) Fiber by Roll-to-Roll Treatment in Atmospheric Ar/O_2 Dielectric Barrier Discharge(DBD) Plasma 被引量:2
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作者 李嘉灵 林捷 +3 位作者 刁颖 胡倩倩 张菁 徐金洲 《Journal of Donghua University(English Edition)》 EI CAS 2011年第1期88-92,共5页
In this work,polyethylene terephthalate(PET) fibers were continuously treated by atmospheric dielectric barrier discharge(DBD) in Ar mixed O2 plasma,and the discharge was characterized by electrical function and optic... In this work,polyethylene terephthalate(PET) fibers were continuously treated by atmospheric dielectric barrier discharge(DBD) in Ar mixed O2 plasma,and the discharge was characterized by electrical function and optical diagnostics.It is found that the interfacial adhesion strength between treated PET fiber and resorcinol formaldehyde latex(RFL)(little)-rubber was improved(about 50%) by the measurement of interfacial shear strength(IFSS) and peel test.The wettability was improved rapidly in the initial treatment time.It is considered that oxidation chemical reaction as the major role of PET fiber surface modification is ahead of the physical etching effect.The high density of atomic oxygen in the plasma by optical emission spectroscopy supports the purpose.According to the scanning electron micrograph(SEM) image in the work,the longer treatment time obviously caused physical etching effect,which shall be less responsible for the improvement of the wettability. 展开更多
关键词 atmospheric pressure plasma polyethylene terephthalate(PET) fiber interfacial shear strength(IFSS) adhesion strength gas analyzer
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A Re-examination of Density Effects in Eddy Covariance Measurements of CO_2 Fluxes 被引量:1
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作者 Heping LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第1期9-16,共8页
Corrections of density effects resulting from air-parcel expansion/compression are important in interpreting eddy covariance fluxes of water vapor and CO2 when open-path systems are used. To account for these effects,... Corrections of density effects resulting from air-parcel expansion/compression are important in interpreting eddy covariance fluxes of water vapor and CO2 when open-path systems are used. To account for these effects, mean vertical velocity and perturbation of the density of dry air are two critical parameters in treating those physical processes responsible for density variations. Based on various underlying assumptions, different studies have obtained different formulas for the mean vertical velocity and perturbation of the density of dry air, leading to a number of approaches to correct density effects. In this study, we re-examine physical processes related to different assumptions that are made to formulate the density effects. Specifically, we re-examine the assumptions of a zero dry air flux and a zero moist air flux in the surface layer, used for treating density variations, and their implications for correcting density effects. It is found that physical processes in relation to the assumption of a zero dry air flux account for the influence of dry air expansion/compression on density variations. Meanwhile, physical processes in relation to the assumption of a zero moist air flux account for the influence of moist air expansion/compression on density variations. In this study, we also re-examine mixing ratio issues. Our results indicate that the assumption of a zero dry air flux favors the use of the mixing ratio relative to dry air, while the assumption of a zero moist air flux favors the use of the mixing ratio relative to the total moist air. Additionally, we compare different formula for the mean vertical velocity, generated by air-parcel expansion/compression, and for density effect corrections using eddy covariance data measured over three boreal ecosystems. 展开更多
关键词 eddy covariance flux of CO2 flux correction density effects air-parcel expansion/compression open-path CO2/H2O infrared gas analyzer
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Correlation between GEM Premier 3000 and Vitros5.1+5600, SYSMEX XN-9000 in Detecting Electrolytes and Red Blood Cell Volume
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作者 Weihua Xue Shunling Li 《Journal of Biomedical Science and Engineering》 2022年第1期44-50,共7页
Objective: To explore the consistency and relevance of the results of the bedside rapid blood gas analyzer GEM premier 3000, the Vitros5.1+5600 biochemical immunoassay analyzer and the SYSMEX XN-9000 automatic blood c... Objective: To explore the consistency and relevance of the results of the bedside rapid blood gas analyzer GEM premier 3000, the Vitros5.1+5600 biochemical immunoassay analyzer and the SYSMEX XN-9000 automatic blood cell analyzer in the central laboratory detecting serum potassium (K<sup>+</sup>), serumsodium (Na<sup>+</sup>), blood glucose (Glu), hemoglobin (Hb) and red blood cell volume (Hct). And to provide a reference for the accurate interpretation of the bedside blood gas analysis report. Method: Usually, ICU patients will be taken arterial blood gas, biochemical and blood samples through the arterial indwelling needle;at the same time patients’ potassium, serum sodium, blood glucose, hemoglobin and red blood cell volume will be detected. This study implemented paired t-test and correlation regression analysis on each group of data, and used the analysis quality requirements (allowable total error) of CLIA’88 proficiency testing program as the criteria for clinical acceptance. Results: The paired t-test showed that the serum potassium, serum sodium and blood glucose detected by GEM premier 3000 and Vitros5.1+5600 were significantly different;and the hemoglobin and red blood cell volume detected by GEM premier 3000 and SYSMEX XN-9000 were significantly different (P < 0.05). The Pearson correlation coefficients (r) of hemoglobin, red blood cell volume and red blood cell volume were 0.860, 0.886, 0.924, 0.841 and 0.856, respectively, and the above test items all had good correlations (P < 0.05). The average (SE) of the paired differences of K<sup>+</sup>, Na<sup>+</sup>, Glu, Hb and Hct detected by the two sets of instruments is less than the allowable error of CLIA’88, and the SE of blood Na<sup>+</sup> and Hb is less than half of the allowable error of CLIA’88. Conclusion: The test results of GEM premier 3000, the central laboratory Vitros5.1+5600 and SYSMEX XN-9000 have good correlation, but the consistency is not good. The test results of GEM premier 3000 cannot replace the central laboratory. 展开更多
关键词 Blood gas analyzer Serum Potassium Serum Sodium Blood Glucose HEMOGLOBIN Red Blood Cell Volume Central Laboratory
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A new method to measure the concentration of argon-xenon gas mixture
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作者 Jiajun Li Mengyun Guan +1 位作者 Youyu Gan Peng Zhang 《Radiation Detection Technology and Methods》 CSCD 2021年第2期280-283,共4页
RGAs are widely used in molec Background RGAs are widely used in molecular component examination,impurity analysis,leak detection and test of vacuum system performance.However,RGAs have different sensitivities to diff... RGAs are widely used in molec Background RGAs are widely used in molecular component examination,impurity analysis,leak detection and test of vacuum system performance.However,RGAs have different sensitivities to different gases,and the sensitivities can change quickly and depend on so many parameters,which make its ability severely limited.Methods In thiswork we established a newpractical method to precisely measure noble gas ratio of argon-xenon gasmixture.Gaseous argon and xenon were controlled,respectively,by two mass flow controller(MFC).A variable leak valve(VLV)was used to introduce the gas mixture sample into the RGA measurement chamber.Gas mixtures with xenon concentration from 200ppm to 20000ppm(by mass)were introduced and tested by RGA.Results The time stability of RGA-measurement system was optimized to 2.1%.A good linearity of MFC-RGA response was achieved,verifying the reliability of RGA in measuring noble gas mixture with component concentration down to several hundred ppm level.Conclusions Since the approach we used in our experiment is gas-species independent,we believe that it can be popularized to other gas species when properly applied. 展开更多
关键词 Residual gas analyzers gas mixture Variable leak valve Noble gas
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