• Analysis of sulfur hexafluoride in seawater - NASA/ADS

    Analysis procedures and instrumentation to measure low levels of sulfur hexafluoride in seawater are described. The minimum detectable level for a 500 mL sample is about 3×10-17 mol/L. Concentrations from 1.5 to 300×10-15 mol/L can be measured with approximately 2% precision. The procedure includes a concentration step employing a trap of Porapak-Qin a dry ice/2-propanol bath.

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  • Sulfur hexafluoride - Wikipedia

    Sulfur hexafluoride or sulphur hexafluoride, is an extremely potent and persistent greenhouse gas that is primarily utilized as an electrical insulator and arc suppressant. It is inorganic, colorless, odorless, non-flammable, and non-toxic. SF 6 has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. It is a hypervalent molecule. Typical for a nonpolar gas, SF 6 is poorly soluble in water but quite soluble in nonpolar organic solvents. It has a density of

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  • Modeling and Simulation of Sulfur Hexafluoride (SF

    Key words: Sulfur Hexafluoride, Batch Distillation, Purification, Regular Solution Theory INTRODUCTION Sulfur hexafluoride (gaz sf6) was first prepared by H. Mossian in 1902 and commercial production of sf 6 was initiated by Allied-Signal Inc., U.S.A., in 1948. The basic properties of Sulfr hexafluoride at 25 oC and 1 atm are summarized in Table 1 [Marshall, 1976

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  • Field-Scale Sulfur Hexafluoride Tracer Experiment to

    ture at the research site. Sulfur hexaluoride (Table 1) was chosen as the tracer gas due to its conservative physiochemical properties (Rattray et al., 1995; Maiss et al., 1996). Sulfur hexaluoride is pri - marily anthropogenic and is found in relatively low concentrations in the atmosphere (<10 pptv) and in the UZ under natural condi-tions.

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  • Dating young groundwater with sulfur hexafluoride: Natural

    Sulfur hexafluoride (SF<SUB6</SUB) is primarily of anthropogenic origin but also occurs naturally. The troposphere concentration of SF<SUB6</SUB has increased from a steady state value of 0.054±0.009 to more than 4 parts per trillion volume during the past 40 years. An analytical procedure was developed for measuring concentrations of SF<SUB6</SUB to less than 0.01 fmol/L in water

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  • Simultaneous determination of sulfur hexafluoride and three

    May 01, 2002 · We have developed an analytical technique for the simultaneous measurement of the four trace gases sulfur hexafluoride (SF 6) and the chlorofluorocarbons CCl 2 F 2 (CFC-12), CCl 3 F (CFC-11) and CCl 2 FCClF 2 (CFC-113) in water and air. Water samples are flame sealed into 350-ml glass ampoules which allow storage and sampling in locations where field measurements are not practical.

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  • Measurement of the diffusion coefficient of sulfur

    Abstract. Sulfur hexafluoride has been widely used in field studies and laboratory experiments to develop a relationship between gas transfer and wind speed. The interpretation of the data from such studies requires the diffusion coefficient of SF 6 ( DSulfr hexafluoride ), which has not previously been measured. In this study, DSulfr hexafluoride has been determined in pure water and in 35‰ NaCl over a temperature range of 5–25°C.

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  • Validation of a Method for Assay of Sulfur Hexafluoride in a

    Jun 13, 2017 · Sulfur hexafluoride was extracted from samples using heptane as the solvent. The method was validated in terms of the following parameters: specificity, linearity, correctness, stability, and inter- and intralaboratory precision. A leading role in detecting disease in the population is played by radiation-based methods, among which ultrasound (US) studies occupy a major role in Russia, due to the widespread economic accessibility of the method for all layers of society, the fact that it is

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  • Simultaneous Determination of Chlorofluorocarbons and Sulfur

    Jul 01, 2016 · The optimal conditions were as follows: trap temperature of −70 °C, purge time of 8 min, purge gas pressure of 310 kPa, desorption time of 30 s, desorption temperature of 90 °C. The method was simple and sensitive. The detection limit were 0.02 pmol kg −1 for CFC-12 and 0.03 fmol kg −1 for SF 6.

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  • A Model for Estimating Future Emissions of Sulfur

    Sulfur hexafluoride (Sulfr hexafluoride), perfluoromethane (CF4) and perfluoroethane (C2F6) are strong greenhouse gases with long (gt;1000 year) atmospheric residence times. We derive emission factors for the major anthropogenic sources and project future emissions for 5 regions and the world. Although firms in many industrialized countries are already limiting emissions, without further policy intervention

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  • Process for measuring degradation of sulfur hexafluoride in

    Process for measuring degradation of sulfur hexafluoride in high voltage systems Patent Sauers, Isidor This invention is a method of detecting the presence of toxic and corrosive by-products in high voltage systems produced by electrically induced degradation of SF.sub.6 insulating gas in the presence of certain impurities.

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  • - The SHAPE of the sulfur hexafluoride molecule in three

    - The central SULFUR atom has a share in TWELVE total electrons, not eight! - The SHAPE of the sulfur hexafluoride molecule in three dimensions agrees with the picture of six fluorine atoms each sharing a pair of electrons with a sulfur center. This structure obeys the octet rule. This molecule does NOT obey the octet rule.

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  • CSIRO PUBLISHING | Animal Production Science

    Measurements of enteric methane (CH4) emissions from individual animals have traditionally been made with indirect calorimetry techniques, which are both accurate and reliable. However, the expense and need for animal training and the extent to which calorimetric results can be extrapolated to free-ranging animals have been questioned and stimulated the development of the sulfur hexafluoride

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  • Atmospheric sulfur hexafluoride in-situ measurements at the

    Dec 01, 2014 · We present in-situ measurements of atmospheric sulfur hexafluoride (Sulfr hexafluoride) conducted by an automated gas chromatograph-electron capture detector system and a gas chromatography/mass spectrometry system at a regional background site, Shangdianzi, in China, from June 2009 to May 2011, using the System for Observation of Greenhouse gases in Europe and Asia and Advanced Global Atmospheric Gases Experiment (AGAGE) techniques.

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  • Sulfur hexafluoride | F6S - PubChem

    The amount of sulfur hexafluoride in the atmosphere totaled 589 metric tons. This amount increases by 7% every year. If released to water or soil, it is not expected to bind to soil particles or suspended particles. Sulfur hexafluoride is expected to move through soil. Sulfur hexafluoride is expected to move into air from soils or water surfaces. Sulfur hexafluoride is not expected to be broken down by microorganisms and may not build up in tissues of fish.

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  • GB/T 11023-2018 PDF English. - Chinese Standard

    High-voltage switchgear sulfur hexafluoride gas Seal test method Published on.2018-12-28 2019-07-01 implementation State market supervision and administration China National Standardization Administration issued Content Foreword I 1 range 1 2 Normative references 1 3 Terms and Definitions 1 4 Test item 4 4.1 Overview 4

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  • Analysis of Sulfur Hexafluoride in Air

    The sulfur hexafluoride analysis system is described in Hall et al. (2007) and Hall et al. (2011). Briefly, gas samples are loaded into a fixed-volume, stainless steel sample loop by flushing the loop, and then injected onto a series of packed columns using a multi-port valve.

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  • Comparison of 20% sulfur hexafluoride with air for

    Purpose: To compare the effect of 20% sulfur hexafluoride (SF 6) with that of air on graft detachment rates for intraocular tamponade in Descemet membrane endothelial keratoplasty (DMEK).

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  • Sulfur Hexafluoride and Potassium Bromide as Groundwater

    Sulfur hexafluoride (SF 6) is an established tracer for use in managed aquifer recharge projects. SF 6 exsolves from groundwater when it encounters trapped air according to Henrylaw. This results in its retardation relative to groundwater flow, which can help determine porous media saturation and flow dynamics.

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  • Asia Pacific Sulfur Hexafluoride Market Forecast to 2027

    The sulfur hexafluoride market in APAC is expected to grow from US$ 95. 62 million in 2019 to US$ 147. 28 million by 2027; it is estimated to grow at a CAGR of 5. 5% from 2020 to 2027. Rising

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  • Comparison of Sulfur Hexafluoride (sf 6) and Air Tamponade in

    de: 41 eyes received air tamponade (group 1) and 41 received gaz sf6 tamponade (group 2). Best spectacle-corrected visual acuity, endothelial cell density, and complications including graft detachment and elevated intraocular pressure were compared. Results: The mean follow-up time was 8 ± 4 months in group 1 and 3 ± 2 months in group 2. Mean best spectacle-corrected visual acuity improved from

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  • Measurement of the diffusion coefficient of sulfur

    Author(s): King, D. B; Saltzman, E. S | Abstract: Sulfur hexafluoride has been widely used in field studies and laboratory experiments to develop a relationship between gas transfer and wind speed. The interpretation of the data from such studies requires the diffusion coefficient of insulating gas (D insulating gas), which has not previously been measured. In this study, D sf 6 has been determined in pure water and

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  • high-voltage high voltage switchgear station

    Shandong Taikai High Voltage Switchgear Co., Ltd. Shandong Taikai High Voltage Switchgear Co., Ltd is a professional research and development production of 72.5kV outdoor high voltage Sulfr hexafluoride circuit breakers and more.Phone: +86-538-8519888 Welcome to official website of Shandong Taikai High Voltage Switchgear Co.,Ltd. Get Price

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  • Simultaneous sulfur hexafluoride and nitrogen multiple-breath

    Nov 04, 2019 · 1. ERJ Open Res. 2019 Nov 4;5(4). pii: 00234-2018. doi: 10.1183/23120541.00234-2018. eCollection 2019 Oct. Simultaneous sulfur hexafluoride and nitrogen multiple-breath washout (MBW) to examine inherent differences in MBW outcomes.

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  • China Sulfur Hexafluoride manufacturer, Nitrogen Trifluoride

    Nov 17, 2015 · China Sulfur Hexafluoride supplier, Nitrogen Trifluoride, Carbonyl Fluoride Manufacturers/ Suppliers - Shanghai Wechem Chemical Co., Ltd

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  • Global High Voltage Circuit Breaker Market (2021) to Witness

    According to a new report published by Zeal Insider, titled, “ Global High Voltage Circuit Breaker Market (2018-2025) – Report, History and Forecast 2014-2025, Breakdown Data by Companies, Key Regions, Types and Application “ The report has offered an all-inclusive analysis of the global High Voltage Circuit Breaker market taking into consideration all the crucial aspects like growth

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  • Correlation for the Viscosity of Sulfur Hexafluoride (SF

    Correlation for the Viscosity of Sulfur Hexafluoride (SF 6) from the Triple Point to 1000 K and Pressures to 50 MPa Sergio E. Quin˜ones-Cisnerosa) Instituto de Investigaciones en Materiales, Universidad Nacional Auto´noma de Me´xico, Apdo. Postal 70-360, Me´xico D.F. 04510, Me´xico Marcia L. Huber

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  • Dating young groundwater with sulfur hexafluoride: Natural

    Sulfur hexafluoride (sf6 gas) is primarily of anthropogenic origin but also occurs naturally. The troposphere concentration of Sulfr hexafluoride has increased from a steady state value of 0.054±0.009 to more than 4 parts per trillion volume during the past 40 years.

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  • Sulfur tetrafluoride - Wikipedia

    Sulfur tetrafluoride is the chemical compound with the formula S F 4.It is a colorless corrosive gas that releases dangerous HF upon exposure to water or moisture. Despite these unwelcome characteristics, this compound is a useful reagent for the preparation of organofluorine compounds, some of which are important in the pharmaceutical and specialty chemical industries.

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