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Sample records for combining vapor gases

  1. Flammability characteristics of combustible gases and vapors

    Energy Technology Data Exchange (ETDEWEB)

    Zabetakis, M. G. [Bureau of Mines, Pittsburgh, PA (United States)

    1964-05-01

    This is a summary of the available limit of flammability, autoignition and burning-rate data for more than 200 combustible gases and vapors in air and other oxidants, as well as of empirical rules and graphs that can be used to predict similar data for thousands of other combustibles under a variety of environmental conditions. Spec$c data are presented on the paraffinic, unsaturated, aromatic, and alicyclic hydrocarbons, alcohols, ethers, aldehydes, ketones, and sulfur compounds, and an assortment of fuels, fuel blends, hydraulic fluids, engine oils, and miscellaneous combustible gases and vapors.

  2. Nanoclusters and Microparticles in Gases and Vapors

    CERN Document Server

    Smirnov, Boris M

    2012-01-01

    Research of processes involving Nanoclusters and Microparticleshas been developing fastin many fields of rescent research, in particular in materials science. To stay at the cutting edge of this development, a sound understanding of the processes is needed. In this work, several processes involving small particles are described, such as transport processes in gases, charging of small particles in gases, chemical processes, atom attachment and quenching of excited atomic particles on surfaces, nucleation, coagulation, coalescence and growth processes for particles and aggregates. This work pres

  3. Table of laser lines in gases and vapors

    Energy Technology Data Exchange (ETDEWEB)

    Beck, R; Englisch, W; Guers, K

    1980-01-01

    Numerous applications of lasers require use of specific wavelengths (gas analysis including remote sensing, Raman spectroscopy, optical pumping, laser chemistry and isotope separation). Scientists active in these fields have been compelled to search, in addition to the available, mostly obsolete, laser-line tables, the entire recent literature in order to find suitable laser transitions. Over 6100 laser transitions are presented. An additional list of the lines arranged in order of wavelength should greatly facilitate the search for a laser material that generates a specific wavelength. Further information has also been supplied by listing the pump transition for each of the FIR lines obtained with the optically pumped organic vapors. In addition to the laser lines, the operating conditions under which emission has been achieved are briefly specified at the top of the list for each active medium. The order in which the atomic laser media are listed is based on the periodic system, beginning with the noble gases, continuing with hydrogen and the alkalies to the halogens and the rare earths. The molecular laser media are arranged in order of chemical composition, beginning with the compounds of noble gases (the excimers), then other diatomic molecules, triatomic molecules, and ending with the more complex molecules of organic vapors. (WHK).

  4. Trace water vapor determination in nitrogen and corrosive gases using infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, L.H.; Niemczyk, T.M. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Chemistry; Stallard, B.R.; Garcia, M.J. [Sandia National Labs., Albuquerque, NM (United States)

    1997-06-01

    The generation of particles in gas handling systems as a result of corrosion is a major concern in the microelectronics industry. The corrosion can be caused by the presence of trace quantities of water in corrosive gases such as HCl or HBr. FTIR spectroscopy has been shown to be a method that can be made compatible with corrosive gases and is capable of detecting low ppb levels of water vapor. In this report, the application of FTIR spectroscopy combined with classical least squares multivariate calibration to detect trace H{sub 2}O in N{sub 2}, HCl and HBr is discussed. Chapter 2 discusses the gas handling system and instrumentation required to handle corrosive gases. A method of generating a background spectrum useful to the measurements discussed in this report, as well as in other application areas such as gas phase environmental monitoring, is discussed in Chapter 3. Experimental results obtained with the first system are presented in Chapter 4. Those results made it possible to optimize the design options for the construction of a dedicate system for low ppb water vapor determination. These designs options are discussed in Chapter 5. An FTIR prototype accessory was built. In addition, a commercially available evacuable FTIR system was obtained for evaluation. Test results obtained with both systems are discussed in Chapter 6. Experiments dealing with the interaction between H{sub 2}O-HCl and potential improvements to the detection system are discussed in Chapter 7.

  5. 30 CFR 71.700 - Inhalation hazards; threshold limit values for gases, dust, fumes, mists, and vapors.

    Science.gov (United States)

    2010-07-01

    ... gases, dust, fumes, mists, and vapors. 71.700 Section 71.700 Mineral Resources MINE SAFETY AND HEALTH... limit values for gases, dust, fumes, mists, and vapors. (a) No operator of an underground coal mine and... limit values adopted by the American Conference of Governmental Industrial Hygienists in “Threshold...

  6. Combined rankine and vapor compression cycles

    Science.gov (United States)

    Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

    2005-04-19

    An organic rankine cycle system is combined with a vapor compression cycle system with the turbine generator of the organic rankine cycle generating the power necessary to operate the motor of the refrigerant compressor. The vapor compression cycle is applied with its evaporator cooling the inlet air into a gas turbine, and the organic rankine cycle is applied to receive heat from a gas turbine exhaust to heat its boiler within one embodiment, a common condenser is used for the organic rankine cycle and the vapor compression cycle, with a common refrigerant, R-245a being circulated within both systems. In another embodiment, the turbine driven generator has a common shaft connected to the compressor to thereby eliminate the need for a separate motor to drive the compressor. In another embodiment, an organic rankine cycle system is applied to an internal combustion engine to cool the fluids thereof, and the turbo charged air is cooled first by the organic rankine cycle system and then by an air conditioner prior to passing into the intake of the engine.

  7. Effect of metabolic gases and water vapor, perfluorocarbon emulsions, and nitric oxide on tissue bubbles during decompression sickness.

    Science.gov (United States)

    Randsøe, Thomas

    2016-05-01

    In aviation and diving, fast decrease in ambient pressure, such as during accidental loss of cabin pressure or when a diver decompresses too fast to sea level, may cause nitrogen (N2) bubble formation in blood and tissue resulting in decompression sickness (DCS). Conventional treatment of DCS is oxygen (O2) breathing combined with recompression.  However, bubble kinetic models suggest, that metabolic gases, i.e. O2 and carbon dioxide (CO2), and water vapor contribute significantly to DCS bubble volume and growth at hypobaric altitude exposures. Further, perfluorocarbon emulsions (PFC) and nitric oxide (NO) donors have, on an experimental basis, demonstrated therapeutic properties both as treatment and prophylactic intervention against DCS. The effect was ascribed to solubility of respiratory gases in PFC, plausible NO elicited nuclei demise and/or N2 washout through enhanced blood flow rate. Accordingly, by means of monitoring injected bubbles in exposed adipose tissue or measurements of spinal evoked potentials (SEPs) in anaesthetized rats, the aim of this study was to: 1) evaluate the contribution of metabolic gases and water vapor to bubble volume at different barometrical altitude exposures, 2) clarify the O2 contribution and N2 solubility from bubbles during administration of PFC at normo- and hypobaric conditions and, 3) test the effect of different NO donors on SEPs during DCS upon a hyperbaric air dive and, to study the influence of  NO on tissue bubbles at high altitude exposures. The results support the bubble kinetic models and indicate that metabolic gases and water vapor contribute significantly to bubble volume at 25 kPa (~10,376 m above sea level) and constitute a threshold for bubble stabilization or decay at the interval of 47-36 kPa (~6,036 and ~7,920 m above sea level). The effect of the metabolic gases and water vapor seemed to compromise the therapeutic properties of both PFC and NO at altitude, while PFC significantly increased bubble

  8. Adsorción física de gases y vapores por carbones

    OpenAIRE

    Martín-Martínez, José Miguel

    1990-01-01

    El establecimiento de las características texturales de carbones es esencial para su utilización en procesos industriales. La evaluación de la textura porosa de carbones se suele realizar mediante adsorción de gases y vapores. Por esta razón, en este libro se pretende plantear las principales estrategias más generalmente empleadas para cualificar la superficie y porosidad de carbones.

  9. Sensing and capture of toxic and hazardous gases and vapors by metal-organic frameworks.

    Science.gov (United States)

    Wang, Hao; Lustig, William P; Li, Jing

    2018-03-13

    Toxic and hazardous chemical species are ubiquitous, predominantly emitted by anthropogenic activities, and pose serious risks to human health and the environment. Thus, the sensing and subsequent capture of these chemicals, especially in the gas or vapor phase, are of extreme importance. To this end, metal-organic frameworks have attracted significant interest, as their high porosity and wide tunability make them ideal for both applications. These tailorable framework materials are particularly promising for the specific sensing and capture of targeted chemicals, as they can be designed to fit a diverse range of required conditions. This review will discuss the advantages of metal-organic frameworks in the sensing and capture of harmful gases and vapors, as well as principles and strategies guiding the design of these materials. Recent progress in the luminescent detection of aromatic and aliphatic volatile organic compounds, toxic gases, and chemical warfare agents will be summarized, and the adsorptive removal of fluorocarbons/chlorofluorocarbons, volatile radioactive species, toxic industrial gases and chemical warfare agents will be discussed.

  10. EFECTOS DE LOS GASES PRODUCTO DE LA COMBUSTIÓN EN LOS GENERADORES DE VAPOR

    Directory of Open Access Journals (Sweden)

    Manuel Plá Duporté

    2011-02-01

    Full Text Available En el trabajo se presentan recopilados, los efectos de ensuciamiento y corrosión que provocan en ungenerador de vapor acuotubular los gases productos de la combustión de combustibles líquidos,explicándose los mecanismos mediante los cuales ocurren tanto en las zonas de alta temperaturacomo en las de baja temperatura  This paper presents gathering of the dirty and corrosion effects of flue gas from liquid fuels, also it’sexplained the process by means of which happen in high and low temperature surfaces in steam watergenerator

  11. The cost-effective synthesis of furan- and thienyl-based microporous polyaminals for adsorption of gases and organic vapors.

    Science.gov (United States)

    Li, Guiyang; Zhang, Biao; Yan, Jun; Wang, Zhonggang

    2016-01-21

    This work reveals that furfural and 2-thenaldehyde can readily react with melamine via "one-step" polycondensation to yield hyper-cross-linked sulfur-, nitrogen- and oxygen-rich microporous polyaminals with promising applications in adsorption of gases and toxic organic vapors.

  12. 42 CFR 84.161 - Man test for gases and vapors; Type B and Type BE respirators; test requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type B and Type BE respirators; test requirements. 84.161 Section 84.161 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air...

  13. 42 CFR 84.159 - Man tests for gases and vapors; supplied-air respirators; general performance requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man tests for gases and vapors; supplied-air respirators; general performance requirements. 84.159 Section 84.159 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  14. 42 CFR 84.160 - Man test for gases and vapors; Type A and Type AE respirators; test requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type A and Type AE respirators; test requirements. 84.160 Section 84.160 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air...

  15. Methods for calculation of engineering parameters for gas separation. [vapor pressure and solubility of gases in organic liquids

    Science.gov (United States)

    Lawson, D. D.

    1979-01-01

    A group additivity method is generated which allows estimation, from the structural formulas alone, of the energy of vaporization and the molar volume at 25 C of many nonpolar organic liquids. Using these two parameters and appropriate thermodynamic relations, the vapor pressure of the liquid phase and the solubility of various gases in nonpolar organic liquids are predicted. It is also possible to use the data to evaluate organic and some inorganic liquids for use in gas separation stages or liquids as heat exchange fluids in prospective thermochemical cycles for hydrogen production.

  16. Heterojunctions formed by annealing of GaSe and InSe layered crystals in zinc vapor

    Directory of Open Access Journals (Sweden)

    Kudrynskyi Z. R.

    2012-12-01

    Full Text Available The article presents a method of creating heterojunc¬tions based on semiconductors with different lattice types. Substrates manufactured from GaSe and InSe layered crystals were annealed in Zn vapor. This way, n-ZnSe–p-GaSe and n-ZnSe–p-InSe heterojunctions were obtained. The obtained heterojunctions are photo¬sensitive in near and infrared spectral regions. This method opens up greate possibilities of producing heterostructures with a desired sensitivity band.

  17. Attenuation of concentration fluctuations of water vapor and other trace gases in turbulent tube flow

    Directory of Open Access Journals (Sweden)

    W. J. Massman

    2008-10-01

    Full Text Available Recent studies with closed-path eddy covariance (EC systems have indicated that the attenuation of fluctuations of water vapor concentration is dependent upon ambient relative humidity, presumably due to sorption/desorption of water molecules at the interior surface of the tube. Previous studies of EC-related tube attenuation effects have either not considered this issue at all or have only examined it superficially. Nonetheless, the attenuation of water vapor fluctuations is clearly much greater than might be expected from a passive tracer in turbulent tube flow. This study reexamines the turbulent tube flow issue for both passive and sorbing tracers with the intent of developing a physically-based semi-empirical model that describes the attenuation associated with water vapor fluctuations. Toward this end, we develop a new model of tube flow dynamics (radial profiles of the turbulent diffusivity and tube airstream velocity. We compare our new passive-tracer formulation with previous formulations in a systematic and unified way in order to assess how sensitive the passive-tracer results depend on fundamental modeling assumptions. We extend the passive tracer model to the vapor sorption/desorption case by formulating the model's wall boundary condition in terms of a physically-based semi-empirical model of the sorption/desorption vapor fluxes. Finally we synthesize all modeling and observational results into a single analytical expression that captures the effects of the mean ambient humidity and tube flow (Reynolds number on tube attenuation.

  18. Remediation of soils combining soil vapor extraction and bioremediation: benzene.

    Science.gov (United States)

    Soares, António Alves; Albergaria, José Tomás; Domingues, Valentina Fernandes; Alvim-Ferraz, Maria da Conceição M; Delerue-Matos, Cristina

    2010-08-01

    This work reports the study of the combination of soil vapor extraction (SVE) with bioremediation (BR) to remediate soils contaminated with benzene. Soils contaminated with benzene with different water and natural organic matter contents were studied. The main goals were: (i) evaluate the performance of SVE regarding the remediation time and the process efficiency; (ii) study the combination of both technologies in order to identify the best option capable to achieve the legal clean up goals; and (iii) evaluate the influence of soil water content (SWC) and natural organic matter (NOM) on SVE and BR. The remediation experiments performed in soils contaminated with benzene allowed concluding that: (i) SVE presented (a) efficiencies above 92% for sandy soils and above 78% for humic soils; (b) and remediation times from 2 to 45 h, depending on the soil; (ii) BR showed to be an efficient technology to complement SVE; (iii) (a) SWC showed minimum impact on SVE when high airflow rates were used and led to higher remediation times for lower flow rates; (b) NOM as source of microorganisms and nutrients enhanced BR but hindered the SVE due the limitation on the mass transfer of benzene from the soil to the gas phase. (c) 2010 Elsevier Ltd. All rights reserved.

  19. Triggering and Energetics of a Single Drop Vapor Explosion: The Role of Entrapped Non-Condensable Gases

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, Roberta Concilio [Royal Institute of Technology, Stockholm (Sweden)

    2009-11-15

    The present work pertains to a research program to study Molten Fuel-Coolant Interactions (MFCI), which may occur in a nuclear power plant during a hypothetical severe accident. Dynamics of the hot liquid (melt) droplet and the volatile liquid (coolant) were investigated in the MISTEE (Micro-Interactions in Steam Explosion Experiments) facility by performing well-controlled, externally triggered, single-droplet experiments, using a high-speed visualization system with synchronized digital cinematography and continuous X-ray radiography. The current study is concerned with the MISTEE-NCG test campaign, in which a considerable amount of non-condensable gases (NCG) are present in the film that enfolds the molten droplet. The SHARP images for the MISTEE-NCG tests were analyzed and special attention was given to the morphology (aspect ratio) and dynamics of the air/ vapor bubble, as well as the melt drop preconditioning. Energetics of the vapor explosion (conversion ratio) were also evaluated. The MISTEE.NCG tests showed two main aspects when compared to the MISTEE test series (without entrapped air). First, analysis showed that the melt preconditioning still strongly depends on the coolant subcooling. Second, in respect to the energetics, the tests consistently showed a reduced conversion ratio compared to that of the MISTEE test series

  20. 42 CFR 84.162 - Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air...

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type C respirators, continuous-flow class and Type CE supplied-air respirators; test requirements. 84.162 Section 84.162 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL...

  1. 42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...

  2. Emission from water vapor and absorption from other gases at 5-7.5 μm in Spitzer-IRS Spectra Of Protoplanetary Disks

    Energy Technology Data Exchange (ETDEWEB)

    Sargent, B. A. [Center for Imaging Science and Laboratory for Multiwavelength Astrophysics, Rochester Institute of Technology, 54 Lomb Memorial Drive, Rochester, NY 14623 (United States); Forrest, W.; Watson, Dan M.; Kim, K. H.; Richter, I.; Tayrien, C. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States); D' Alessio, P.; Calvet, N. [Department of Astronomy, The University of Michigan, 500 Church Street, 830 Dennison Building, Ann Arbor, MI 48109 (United States); Furlan, E. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Green, J. [Department of Astronomy, University of Texas, 1 University Station, Austin, TX 78712 (United States); Pontoppidan, K., E-mail: baspci@rit.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2014-09-10

    We present spectra of 13 T Tauri stars in the Taurus-Auriga star-forming region showing emission in Spitzer Space Telescope Infrared Spectrograph 5-7.5 μm spectra from water vapor and absorption from other gases in these stars' protoplanetary disks. Seven stars' spectra show an emission feature at 6.6 μm due to the ν{sub 2} = 1-0 bending mode of water vapor, with the shape of the spectrum suggesting water vapor temperatures >500 K, though some of these spectra also show indications of an absorption band, likely from another molecule. This water vapor emission contrasts with the absorption from warm water vapor seen in the spectrum of the FU Orionis star V1057 Cyg. The other 6 of the 13 stars have spectra showing a strong absorption band, peaking in strength at 5.6-5.7 μm, which for some is consistent with gaseous formaldehyde (H{sub 2}CO) and for others is consistent with gaseous formic acid (HCOOH). There are indications that some of these six stars may also have weak water vapor emission. Modeling of these stars' spectra suggests these gases are present in the inner few AU of their host disks, consistent with recent studies of infrared spectra showing gas in protoplanetary disks.

  3. Combination downflow-upflow vapor-liquid separator

    Energy Technology Data Exchange (ETDEWEB)

    Kidwell, John H. (Uniontown, OH); Prueter, William P. (Alliance, OH); Eaton, Andrew M. (Alliance, OH)

    1987-03-10

    An improved vapor-liquid separator having a vertically disposed conduit for flow of a mixture. A first, second and third plurality of curved arms penetrate and extend within the conduit. A cylindrical member is radially spaced from the conduit forming an annulus therewith and having perforations and a retaining lip at its upper end.

  4. Combination downflow-upflow vapor-liquid separator

    Energy Technology Data Exchange (ETDEWEB)

    Kidwell, J.H.; Prueter, W.P.; Eaton, A.M.

    1987-03-10

    An improved vapor-liquid separator is described having a vertically disposed conduit for flow of a mixture. A first, second and third plurality of curved arms penetrate and extend within the conduit. A cylindrical member is radially spaced from the conduit forming an annulus therewith and having perforations and a retaining lip at its upper end. 11 figs.

  5. Evaluation of a process for the removal of gases contained in geothermal steam through condensation and re-evaporation; Evaluacion de un proceso de remocion de gases contenidos en el vapor geotermico, por medio de la condensacion y de revaporacion

    Energy Technology Data Exchange (ETDEWEB)

    Angulo C, Raul; Lam Rea, Luis; Garmino, Hector; Jimenez, Humberto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1986-12-31

    The Cerro Prieto I Geothermal Field, developed and operated by the Comision Federal de Electricidad (CFE), has currently an installed electric power generation capacity of 180 MW and is at a very advanced stage in the development of Cerro Prieto II and III, which will allow to raise the generation capacity to 620 MW. During the exploitation of a geothermal field, in producing steam with the purpose of generating electricity, brines and waste gases are obtained. The hydrogen sulfide exhaust to the environment implies pollution problems, for this reason processes have been developed for the oxidation of these gases downstream the turbogenerator either in the flow of separated gases in the steam condensation or in the condensate produced. The Instituto de Investigaciones Electricas (IIE) has collaborated with CFE in the evaluation of the environmental impact of this gas and in the development of the processes for its abatement. [Espanol] El campo geotermico de Cerro Prieto I, desarrollado y operado por la Comision Federal de Electricidad (CFE), actualmente tiene una capacidad instalada de generacion de energia electrica de 180 MW, y se encuentra en etapa muy avanzada, el desarrollo de Cerro Prieto II y III, lo que permitira incrementar la capacidad de generacion a 620 MW. Durante la explotacion de un campo geotermico, al producir vapor con el proposito de generar electricidad, se obtienen salmueras y gases de desecho. La descarga de acido sulfhidrico a la atmosfera implica problemas de contaminacion, por esta razon se han desarrollado procesos para la oxidacion de este gas aguas abajo de la turbina generadora, ya sea en la corriente de gases que se separan en la condensacion del vapor o en el condensado producido. El Instituto de Investigaciones Electricas (IIE) ha colaborado con la CFE en la evaluacion del impacto ambiental de este gas y en el desarrollo de sus procesos de abatimiento.

  6. Evaluation of a process for the removal of gases contained in geothermal steam through condensation and re-evaporation; Evaluacion de un proceso de remocion de gases contenidos en el vapor geotermico, por medio de la condensacion y de revaporacion

    Energy Technology Data Exchange (ETDEWEB)

    Angulo C, Raul; Lam Rea, Luis; Garmino, Hector; Jimenez, Humberto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1985-12-31

    The Cerro Prieto I Geothermal Field, developed and operated by the Comision Federal de Electricidad (CFE), has currently an installed electric power generation capacity of 180 MW and is at a very advanced stage in the development of Cerro Prieto II and III, which will allow to raise the generation capacity to 620 MW. During the exploitation of a geothermal field, in producing steam with the purpose of generating electricity, brines and waste gases are obtained. The hydrogen sulfide exhaust to the environment implies pollution problems, for this reason processes have been developed for the oxidation of these gases downstream the turbogenerator either in the flow of separated gases in the steam condensation or in the condensate produced. The Instituto de Investigaciones Electricas (IIE) has collaborated with CFE in the evaluation of the environmental impact of this gas and in the development of the processes for its abatement. [Espanol] El campo geotermico de Cerro Prieto I, desarrollado y operado por la Comision Federal de Electricidad (CFE), actualmente tiene una capacidad instalada de generacion de energia electrica de 180 MW, y se encuentra en etapa muy avanzada, el desarrollo de Cerro Prieto II y III, lo que permitira incrementar la capacidad de generacion a 620 MW. Durante la explotacion de un campo geotermico, al producir vapor con el proposito de generar electricidad, se obtienen salmueras y gases de desecho. La descarga de acido sulfhidrico a la atmosfera implica problemas de contaminacion, por esta razon se han desarrollado procesos para la oxidacion de este gas aguas abajo de la turbina generadora, ya sea en la corriente de gases que se separan en la condensacion del vapor o en el condensado producido. El Instituto de Investigaciones Electricas (IIE) ha colaborado con la CFE en la evaluacion del impacto ambiental de este gas y en el desarrollo de sus procesos de abatimiento.

  7. Effect of ultraviolet illumination and ambient gases on the photoluminescence and electrical properties of nanoporous silicon layer for organic vapor sensor.

    Science.gov (United States)

    Atiwongsangthong, Narin

    2012-08-01

    The purpose of this research, the nanoporous silicon layer were fabricated and investigated the physical properties such as photoluminescence and the electrical properties in order to develop organic vapor sensor by using nanoporous silicon. The Changes in the photoluminescence intensity of nanoporous silicon samples are studied during ultraviolet illumination in various ambient gases such as nitrogen, oxigen and vacuum. In this paper, the nanoporous silicon layer was used as organic vapor adsorption and sensing element. The advantage of this device are simple process compatible in silicon technology and usable in room temperature. The structure of this device consists of nanoporous silicon layer which is formed by anodization of silicon wafer in hydrofluoric acid solution and aluminum electrode which deposited on the top of nanoporous silicon layer by evaporator. The nanoporous silicon sensors were placed in a gas chamber with various organic vapor such as ethanol, methanol and isopropyl alcohol. From studying on electrical characteristics of this device, it is found that the nanoporous silicon layer can detect the different organic vapor. Therefore, the nanoporous silicon is important material for organic vapor sensor and it can develop to other applications about gas sensors in the future.

  8. Combined ground- and satellite-based profiling of temperature and water vapor

    International Nuclear Information System (INIS)

    Stankov, B.B.; Westwater, E.R.; Snider, J.B.; Churnside, J.H.

    1994-01-01

    The fusion or integration of meteorological and radiative data from a range of instrumentation into a representative picture of temperature, water vapor, and clouds over a CART domain will be a challenging task for four-dimensional data assimilation models. In the work reported here, we have summarized work supported by DOE's algorithm development program including combined RASS and TIROS Operational Vertical Sounder (TOVS) temperature sensing, water vapor profiles from dual-channel radiometers, and neural network radiometric temperature retrievals

  9. Analysis regarding steam generator furnace's incident heat, temperature and composition of combustion gases; Analisis de calor incidente, temperatura y composicion de gases de combustion en hornos de generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Diego Marin, Antonio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    In order to obtain more precise evaluations of the combustion process in the furnace of a steam generator a suction pyrometer has been integrated to measure the temperature of the combustion gases; an ellipsoidal radiometer to measure the incident heat by thermal radiation in the water walls; a water cooled probe to determine the particle concentration, as well as a water cooled probe to determine the composition of the combustion gases present. This document clarifies the form of use of these instruments and their engineering specifications, simultaneously presenting an analysis that considers, unlike others, the internal conditions of the furnace to obtain a more precise evaluation of the efficiency that the combustion process presents and bases for the taking of preventive actions in specific zones of the furnace. Thus, the present work exhibits instruments and techniques of analysis to study the phenomena occurring within a steam generator. [Spanish] Con el fin de obtener evaluaciones mas precisas del proceso de combustion en el horno de un generador de vapor, se ha integrado un pirometro de succion para medir la temperatura de los gases de combustion; un radiometro elipsoidal para medir el calor incidente por radiacion termica en las paredes del agua; una sonda enfriada con agua para determinar la concentracion de particulas, asi como una sonda refrigerada con agua para determinar la composicion de los gases de combustion presentes. Este documento aclara la forma de uso de estos instrumentos y sus especificaciones tecnicas, a la vez que presenta un analisis que considera, a diferencia de otros, las condiciones internas del horno para obtener una evaluacion mas precisa sobre la eficiencia del proceso de combustion y bases para la toma de acciones preventivas en zonas especificas del horno. Asi, el presente trabajo exhibe instrumentos y tecnicas de analisis para estudiar los fenomenos que ocurren dentro de un generador de vapor.

  10. Mechanics of gas-vapor bubbles

    NARCIS (Netherlands)

    Hao, Yue; Zhang, Yuhang; Prosperetti, Andrea

    2017-01-01

    Most bubbles contain a mixture of vapor and incondensible gases. While the limit cases of pure vapor and pure gas bubbles are well studied, much less is known about the more realistic case of a mixture. The bubble contents continuously change due to the combined effects of evaporation and

  11. "Super-Fog"--A Combination of Smoke and Water Vapor That Produces Zero Visibility over Roadways

    Science.gov (United States)

    Gary L. Achtemeier

    2002-01-01

    Forest and agricultural burning release chemical compounds and particulate matter into the atmosphere. Although most of this material contributes to visibility reductions through haze and provldes chemical constituents available for reactions with other atmospheric pollutants, there are occasions when smoke is entrapped locally and combines with water vapor to...

  12. Analysis of combined heat and mass transfer of water- Vapor in a ...

    African Journals Online (AJOL)

    In this paper, the combined heat and mass transfer of water-vapor into a cylindrical zeolite adsorber has been numerically simulated The twodimensional heat and mass transfer equations are numerically solved using gPROMS program - a general Process Modeling System {lJ program, inserting the proper initial and ...

  13. Analysis of combined heat and mass transfer of water-vapor in a ...

    African Journals Online (AJOL)

    Jn this paper, the combined heat and mass transfer of water-vapor into a cylindrical zeolite adsorber has been numerically simulated The twodimensional heat and mass transfer equations are numerically solved using gPROMS program - a general Process Modeling System [J] program, inserting the proper initial and ...

  14. Acidity of vapor plume from cooling tower mixed with flue gases emitted from coal-fired power plant.

    Science.gov (United States)

    Hlawiczka, Stanislaw; Korszun, Katarzyna; Fudala, Janina

    2016-06-01

    Acidity of products resulting from the reaction of flue gas components emitted from a coal-fired power plant with water contained in a vapor plume from a wet cooling tower was analyzed in a close vicinity of a power plant (710 m from the stack and 315 m from the cooling tower). Samples of this mixture were collected using a precipitation funnel where components of the mixed plumes were discharged from the atmosphere with the rainfall. To identify situations when the precipitation occurred at the same time as the wind directed the mixed vapor and flue gas plumes above the precipitation funnel, an ultrasound anemometer designed for 3D measurements of the wind field located near the funnel was used. Precipitation samples of extremely high acidity were identified - about 5% of samples collected during 12 months showed the acidity below pH=3 and the lowest recorded pH was 1.4. During the measurement period the value of pH characterizing the background acidity of the precipitation was about 6. The main outcome of this study was to demonstrate a very high, and so far completely underestimated, potential of occurrence of episodes of extremely acid depositions in the immediate vicinity of a coal-fired power plant. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure.

    Science.gov (United States)

    Wang, Jinzhi; Hu, Zhengyi; Xu, Xingkai; Jiang, Xia; Zheng, Binghui; Liu, Xiaoning; Pan, Xubin; Kardol, Paul

    2014-08-01

    Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH3), and greenhouse gases (GHG), including nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N2O, CH4, and CO2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg(-)(1) DM to 274.2, 30.4, and 314.0 mg kg(-1) DM, respectively. Earthworms and amendments significantly decreased N2O and CH4 emissions. Emission of CO2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH3 emission ranged from 3.0 to 8.1 g kg(-1) DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N2O, CH4, and NH3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure

    International Nuclear Information System (INIS)

    Wang, Jinzhi; Hu, Zhengyi; Xu, Xingkai; Jiang, Xia; Zheng, Binghui; Liu, Xiaoning; Pan, Xubin; Kardol, Paul

    2014-01-01

    Highlights: • Earthworms significantly decreased emissions of N 2 O and CH 4 , but had a marginal effect on CO 2 emission. • NH 3 , N 2 O, and CH 4 emissions were significantly reduced by reed straw and zeolite, CO 2 emission was increased by reed straw. • Combined pre-composting and vermicomposting with reed straw and zeolite would be recommended for disposal of duck manure. - Abstract: Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH 3 ), and greenhouse gases (GHG), including nitrous oxide (N 2 O), methane (CH 4 ), and carbon dioxide (CO 2 ). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH 3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH 3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N 2 O, CH 4 , and CO 2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg −1 DM to 274.2, 30.4, and 314.0 mg kg −1 DM, respectively. Earthworms and amendments significantly decreased N 2 O and CH 4 emissions. Emission of CO 2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH 3 emission ranged from 3.0 to 8.1 g kg −1 DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N 2 O, CH 4 , and NH 3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer

  17. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jinzhi [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Hu, Zhengyi, E-mail: zhyhu@ucas.ac.cn [College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Xu, Xingkai [State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 (China); Jiang, Xia; Zheng, Binghui [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); Liu, Xiaoning [College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Pan, Xubin [Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing 100029 (China); Kardol, Paul [Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, S 90183 Umeå (Sweden)

    2014-08-15

    Highlights: • Earthworms significantly decreased emissions of N{sub 2}O and CH{sub 4}, but had a marginal effect on CO{sub 2} emission. • NH{sub 3}, N{sub 2}O, and CH{sub 4} emissions were significantly reduced by reed straw and zeolite, CO{sub 2} emission was increased by reed straw. • Combined pre-composting and vermicomposting with reed straw and zeolite would be recommended for disposal of duck manure. - Abstract: Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH{sub 3}), and greenhouse gases (GHG), including nitrous oxide (N{sub 2}O), methane (CH{sub 4}), and carbon dioxide (CO{sub 2}). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH{sub 3} and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH{sub 3} and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N{sub 2}O, CH{sub 4}, and CO{sub 2} emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg{sup −1} DM to 274.2, 30.4, and 314.0 mg kg{sup −1} DM, respectively. Earthworms and amendments significantly decreased N{sub 2}O and CH{sub 4} emissions. Emission of CO{sub 2} was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH{sub 3} emission ranged from 3.0 to 8.1 g kg{sup −1} DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N{sub 2}O, CH{sub 4}, and NH{sub 3} from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer.

  18. Performance Analysis of Solar Combined Ejector-Vapor Compression Cycle Using Environmental Friendly Refrigerants

    Directory of Open Access Journals (Sweden)

    A. B. Kasaeian

    2013-04-01

    Full Text Available In this study, a new model of a solar combined ejector-vapor compression refrigeration system has been considered. The system is equipped with an internal heat exchanger to enhance the performance of the cycle. The effects of working fluid and operating conditions on the system performance including COP, entrainment ratio (ω, compression ratio (rp and exergy efficiency were investigated. Some working fluids suggested are: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e and R1234ze(z. The results show that R114 and R1234ze(e yield the highest COP and exergy efficiency followed by R123, R245fa, R365mfc, R141b, R152a and R600a. It is noticed that the COP value of the new solar ejector-vapor compression refrigeration cycle is higher than that of the conventional ejector cycle with R1234ze(e for all operating conditions. This paper also demonstrates that R1234ze(e will be a suitable refrigerant in the solar combined ejector-vapor compression refrigeration system, due to its environmental friendly properties and better performance. ABSTRAK: Kajian ini menganalisa model baru sistem penyejukan mampatan gabungan ejektor-wap solar.Sistem ini dilengkapi dengan penukar haba dalaman untuk meningkatkan prestasi kitaran.Kesan bendalir bekerja dan keadaan operasi pada prestasi sistem termasuk COP, nisbah pemerangkapan (ω, nisbah mampatan (rp dan kecekapan eksergi telah disiasat.Beberapa bendalir bekerja yang dicadangkan adalah: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e dan R1234ze(z.Hasil kajian menunjukkan R114 dan R1234ze(e menghasilkan COP dan kecekapan eksergi tertinggi diikuti oleh R123, R245fa, R365mfc, R141b, R152a dan R600a.Didapati nilai COP kitaran penyejukan mampatan bagi ejektor-wap solar baru adalah lebih tinggi daripada kitaran ejektor konvensional dengan R1234ze(e bagi semua keadaan operasi.Kertas kerja ini juga menunjukkan bahawa R1234ze(e boleh menjadi penyejuk yang sesuai dalam sistem penyejukan mampatan gabungan ejektor

  19. Combined production og energy by vapor-gas unit on natural gas in Skopje (Macedonia)

    International Nuclear Information System (INIS)

    Armenski, Slave; Dimitrov, Konstantin; Tashevski, Done

    1998-01-01

    The steam and gas turbine power plant for combine heat (for district heating of Skopje - the capital of Macedonia) and power (connected to the grid) production is analyzed and determined. Two variants of power plants are analyzed: power plant with gas turbine, heat recovery steam generator and a back pressure steam turbine; and power plant with two gas turbines, two heat recovery steam generators (HRSG) and one back pressure steam turbine. The power plant would operate on natural gas as the main fuel source. It will be burnt in the gas turbine as well in the HRSG as an auxiliary fuel.The backup fuel for the gas turbine would be light oil. In normal operation, the HRSG uses the waste heat of the exhaust gases from the gas turbine. During gas turbine shutdowns, the HRSG can continue to generate the maximum steam capacity. The heat for district heating would be produce in HRSG by flue gases from the gas turbine and in the heat exchanger by condensed steam from back pressure turbine. The main parameters of the combined power plant, as: overall energy efficiency, natural gas consumption, natural gas saving are analyzed and determined in comparison with separated production of heat (for district heating) and power (for electrical grid). (Author)

  20. Fabrication and characterization of a cell electrostimulator device combining physical vapor deposition and laser ablation

    Science.gov (United States)

    Aragón, Angel L.; Pérez, Eliseo; Pazos, Antonio; Bao-Varela, Carmen; Nieto, Daniel

    2017-08-01

    In this work we present the process of fabrication and optimization of a prototype of a cell electrostimulator device for medical application combining physical vapor deposition and laser ablation. The fabrication of the first prototype begins with a deposition of a thin layer of 200 nm of aluminium on a borosilicate glass substrate using physical vapor deposition (PVD). In the second stage the geometry design of the electrostimulator is made in a CAD-like software available in a Nd:YVO4 Rofin Power line 20E, operating at the fundamental wavelength of 1064 nm and 20 ns pulse width. Choosing the proper laser parameters the negative of the electrostimulator desing is ablated. After that the glass is assembled between two polycarbonate sheets and a thick sheet of polydimethylsiloxane (PDMS). The PDMS sheet has a round hole in where cells are placed. There is also included a thin soda-lime silicate glass (100 μm) between the electrostimulator and the PMDS to prevent the cells for being in contact with the electric circuit. In order to control the electrical signal applied to the electrostimulator is used a digital I/O device from National Instruments (USB-6501) which provides 5 V at the output monitored by a software programmed in LabVIEW. Finally, the optical and electrical characterization of the cell electrostimulator device is presented.

  1. Gases in molten salts

    CERN Document Server

    Tomkins, RPT

    1991-01-01

    This volume contains tabulated collections and critical evaluations of original data for the solubility of gases in molten salts, gathered from chemical literature through to the end of 1989. Within the volume, material is arranged according to the individual gas. The gases include hydrogen halides, inert gases, oxygen, nitrogen, hydrogen, carbon dioxide, water vapor and halogens. The molten salts consist of single salts, binary mixtures and multicomponent systems. Included also, is a special section on the solubility of gases in molten silicate systems, focussing on slags and fluxes.

  2. Experimental study of arsenic speciation in vapor phase to 500°C: Implications for As transport and fractionation in low-density crustal fluids and volcanic gases.

    OpenAIRE

    Pokrovski , Gleb S.; Zakirov , Ildar V.; Roux , Jacques; Testemale , Denis; Hazemann , Jean-Louis; Y. U. Bychkov , Andrew; V. Golikova , Galina

    2002-01-01

    The stoichiometry and stability of arsenic gaseous complexes were determined in the system As-H2O ± NaCl ± HCl ± H2S at temperatures up to 500°C and pressures up to 600 bar, from both measurements of As(III) and As(V) vapor-liquid and vapor-solid partitioning, and X-ray absorption fine structure (XAFS) spectroscopic study of As(III)-bearing aqueous fluids. Vapor-aqueous solution partitioning for As(III) was measured from 250 to 450°C at the saturated vapor pressure of the system (Psat) with a...

  3. Multi-layer Retrievals of Greenhouse Gases from a Combined Use of GOSAT TANSO-FTS SWIR and TIR

    Science.gov (United States)

    Kikuchi, N.; Kuze, A.; Kataoka, F.; Shiomi, K.; Hashimoto, M.; Suto, H.; Knuteson, R. O.; Iraci, L. T.; Yates, E. L.; Gore, W.; Tanaka, T.; Yokota, T.

    2016-12-01

    The TANSO-FTS sensor onboard GOSAT has three frequency bands in the shortwave infrared (SWIR) and the fourth band in the thermal infrared (TIR). Observations of high-resolution spectra of reflected sunlight in the SWIR are extensively utilized to retrieve column-averaged concentrations of the major greenhouse gases such as carbon dioxide (XCO2) and methane (XCH4). Although global XCO2 and XCH4 distribution retrieved from SWIR data can reduce the uncertainty in the current knowledge about sources and sinks of these gases, information on the vertical profiles would be more useful to constrain the surface flux and also to identify the local emission sources. Based on the degrees of freedom for signal, Kulawik et al. (2016, IWGGMS-12 presentation) shows that 2-layer information on the concentration of CO2 can be extracted from TANSO-FTS SWIR measurements, and the retrieval error is predicted to be about 5 ppm in the lower troposphere. In this study, we present multi-layer retrievals of CO2 and CH4 from a combined use of measurements of TANSO-FTS SWIR and TIR. We selected GOSAT observations at Railroad Valley Playa in Nevada, USA, which is a vicarious calibration site for TANSO-FTS, as we have various ancillary data including atmospheric temperature and humidity taken by a radiosonde, surface temperature, and surface emissivity with a ground based FTS. All of these data are useful especially for retrievals using TIR spectra. Currently, we use the 700-800 cm-1 and 1200-1300 cm-1 TIR windows for CO2 and CH4 retrievals, respectively, in addition to the SWIR bands. We found that by adding TIR windows, 3-layer information can be extracted, and the predicted retrieval error in the CO2 concentration was reduced about 1 ppm in the lower troposphere. We expect that the retrieval error could be further reduced by optimizing TIR windows and by reducing systematic forward model errors.

  4. Control of strain in GaN by a combination of H2 and N2 carrier gases

    International Nuclear Information System (INIS)

    Yamaguchi, Shigeo; Kariya, Michihiko; Kosaki, Masayoshi; Yukawa, Yohei; Nitta, Shugo; Amano, Hiroshi; Akasaki, Isamu

    2001-01-01

    We study the effect of a combination of N 2 and H 2 carrier gases on the residual strain and crystalline properties of GaN, and we propose its application to the improvement of crystalline quality of GaN/Al 0.17 Ga 0.83 N multiple quantum well (MQW) structures. GaN was grown with H 2 or N 2 carrier gas (H 2 - or N 2 - GaN) on an AlN low-temperature-deposited buffer layer. A (0001) sapphire substrate was used. N 2 - GaN was grown on H 2 - GaN. The total thickness was set to be 1.5 μm, and the ratio of N 2 - GaN thickness to the total thickness, x, ranged from 0 to 1. With increasing x, the tensile stress in GaN increased. Photoluminescence intensity at room temperature was much enhanced. Moreover, the crystalline quality of GaN/Al 0.17 Ga 0.83 N MQW was much higher when the MQW was grown with N 2 on H 2 - GaN than when it was grown with H 2 on H 2 - GaN. These results were due to the achievement of control of strain in GaN using a combination of N 2 - GaN and H 2 - GaN. [copyright] 2001 American Institute of Physics

  5. Development of a hybrid refrigerator combining thermoelectric and vapor compression technologies

    International Nuclear Information System (INIS)

    Vian, J.G.; Astrain, D.

    2009-01-01

    A domestic refrigerator with three compartments has been developed: refrigerator compartment, at 4 deg. C (vapor compression cooling system); freezer compartment, at -22 deg. C (vapor compression cooling system); and a new super-conservation compartment, at 0 deg. C (thermoelectric cooling system). The thermoelectric system designed for the super-conservation compartment eliminates the oscillation of its temperature due to the start and stop compressor cycles, obtaining a constant temperature and thus, a better preservation of the food. For the design and optimization of this application, a computational model, based in the numerical method of finite differences, has been developed. This model allows to simulate the complete hybrid refrigerator (vapor compression-thermoelectricity). The accuracy of the model has been experimentally checked, with a maximum error of 1.2 deg. C for temperature values, and 8% for electric power consumption. By simulations with the computational model, the design of the refrigerator has been optimized, obtaining a final prototype highly competitive, by the features on food preservation and power consumption: 1.15 kW h per day (48.1 W) for an ambient temperature of 25 deg. C. According to European rules, this power consumption value means that this new refrigerator could be included on energy efficiency class B.

  6. Industrial gases

    International Nuclear Information System (INIS)

    Hunter, D.; Jackson, D.; Coeyman, M.

    1993-01-01

    Industrial gas companies have fought hard to boost sales and hold margins in the tough economic climate, and investments are well down from their 1989-'91 peak. But 'our industry is still very strong long term' says Alain Joly, CEO of industry leader L'Air Liquide (AL). By 1994, if a European and Japanese recovery follows through on one in the U.S., 'we could see major [investment] commitments starting again,' he says. 'Noncryogenic production technology is lowering the cost of gas-making possible new applications, oxygen is getting plenty of attention in the environmental area, and hydrogen also fits into the environmental thrust,' says Bob Lovett, executive v.p./gases and equipment with Air Products ampersand Chemicals (AP). Through the 1990's, 'Industrial gases could grow even faster than in the past decade,' he says. Virtually a new generation of new gases applications should become reality by the mid-1990s, says John Campbell, of industry consultants J.R. Campbell ampersand Associates (Lexington, MA). Big new oxygen volumes will be required for powder coal injection in blast furnaces-boosting a steel mill's requirement as much as 40% and coal gasification/combined cycle (CGCC). Increased oil refinery hydroprocessing needs promise hydrogen requirements

  7. Ionic liquids. Combination of combustion calorimetry with high-level quantum chemical calculations for deriving vaporization enthalpies.

    Science.gov (United States)

    Emel'yanenko, Vladimir N; Verevkin, Sergey P; Heintz, Andreas; Schick, Christoph

    2008-07-10

    In this work, the molar enthalpies of formation of the ionic liquids [C2MIM][NO3] and [C4MIM][NO3] were measured by means of combustion calorimetry. The molar enthalpy of fusion of [C2MIM][NO3] was measured using differential scanning calorimetry. Ab initio calculations of the enthalpy of formation in the gaseous phase have been performed for the ionic species using the G3MP2 theory. We have used a combination of traditional combustion calorimetry with modern high-level ab initio calculations in order to obtain the molar enthalpies of vaporization of a series of the ionic liquids under study.

  8. Adsorption and reaction mechanism of arsenic vapors over γ-Al2O3 in the simulated flue gas containing acid gases.

    Science.gov (United States)

    Hu, Hongyun; Chen, Dunkui; Liu, Huan; Yang, Yuhan; Cai, Hexun; Shen, Junhao; Yao, Hong

    2017-08-01

    Arsenic emission from fuel combustion and metal smelting flue gas causes serious pollution. Addition of sorbents is a promising way for the arsenic capture from high temperature flue gas. However, it is difficult to remove arsenic from SO 2 /HCl-rich flue gas due to the competitive reaction of the sorbents with arsenic and these acid gases. To solve this problem, arsenic adsorption over γ-Al 2 O 3 was studied in this work to evaluate its adsorption mechanism, resistance to acid gases as well as regeneration behavior. The results show that γ-Al 2 O 3 had good resistance to acid gases and the arsenic adsorption by γ-Al 2 O 3 could be effectively carried out at a wide temperature range between 573 and 1023 K. Nevertheless, adsorption at higher-temperature (like 1173 K) leaded to the decrease of surface area and the rearrangement of crystal structure of γ-Al 2 O 3 , reducing the active sites for arsenic adsorption. The adsorption of arsenic was confirmed to occur at different active sites in γ-Al 2 O 3 by forming various adsorbed species. Increasing temperature facilitated arsenic transformation into more stable chemisorbed As 3+ and As 5+ which were difficult to remove through thermal treatment regeneration. Fortunately, the regeneration of spent γ-Al 2 O 3 could be well performed using NaOH solution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Greenhouse Gases

    Science.gov (United States)

    ... Production of Hydrogen Use of Hydrogen Greenhouse Gases Basics | | Did you know? Without naturally occurring greenhouse gases, the earth would be too cold to support life as we know it. Without the greenhouse effect, ...

  10. Evaluation of Different Gases and Gas Combinations for On-Farm Euthanasia of Pre-Weaned Pigs

    Directory of Open Access Journals (Sweden)

    Nikki Kells

    2018-03-01

    Full Text Available The aim of this research was to evaluate the welfare of pre-weaned piglets euthanised using three different gas treatments: 100% carbon dioxide (CO2, 100% argon (Ar or a mixture of 60% Ar/40% carbon dioxide (Ar/CO2. Two studies (n = 5 piglets/treatment/study were conducted: (1 behavioural and physiological data were collected from conscious piglets during exposure to test gases via immersion in a pre-filled chamber and (2 electrophysiological data were collected from lightly anaesthetised, intubated and mechanically ventilated piglets exposed to the same test gases. Based on the duration of escape attempts and laboured breathing, piglets exposed to 100% CO2 experienced more stress than piglets exposed to 100% Ar prior to loss of consciousness, but there appeared to be no advantage of mixing Ar with CO2 on indices of animal welfare. However, spectral analysis of the electroencephalogram revealed no changes consistent with nociception during exposure to any of the three gas treatments. Based on the behavioural response to gas exposure, all gases tested caused signs of stress prior to piglets losing consciousness and hence alternative methods of euthanasia need to be evaluated.

  11. Evaluation of Different Gases and Gas Combinations for On-Farm Euthanasia of Pre-Weaned Pigs.

    Science.gov (United States)

    Kells, Nikki; Beausoleil, Ngaio; Johnson, Craig; Sutherland, Mhairi

    2018-03-16

    The aim of this research was to evaluate the welfare of pre-weaned piglets euthanised using three different gas treatments: 100% carbon dioxide (CO₂), 100% argon (Ar) or a mixture of 60% Ar/40% carbon dioxide (Ar/CO₂). Two studies (n = 5 piglets/treatment/study) were conducted: (1) behavioural and physiological data were collected from conscious piglets during exposure to test gases via immersion in a pre-filled chamber and (2) electrophysiological data were collected from lightly anaesthetised, intubated and mechanically ventilated piglets exposed to the same test gases. Based on the duration of escape attempts and laboured breathing, piglets exposed to 100% CO₂ experienced more stress than piglets exposed to 100% Ar prior to loss of consciousness, but there appeared to be no advantage of mixing Ar with CO₂ on indices of animal welfare. However, spectral analysis of the electroencephalogram revealed no changes consistent with nociception during exposure to any of the three gas treatments. Based on the behavioural response to gas exposure, all gases tested caused signs of stress prior to piglets losing consciousness and hence alternative methods of euthanasia need to be evaluated.

  12. 40 CFR 796.1950 - Vapor pressure.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) CHEMICAL FATE TESTING GUIDELINES Physical and Chemical Properties § 796.1950 Vapor pressure. (a.... In addition, chemicals that are likely to be gases at ambient temperatures and which have low water... gases until the measured vapor pressure is constant, a process called “degassing.” Impurities more...

  13. Thermodynamic model for predicting equilibrium conditions of clathrate hydrates of noble gases + light hydrocarbons: Combination of Van der Waals–Platteeuw model and sPC-SAFT EoS

    International Nuclear Information System (INIS)

    Abolala, Mostafa; Varaminian, Farshad

    2015-01-01

    Highlights: • Applying sPC-SAFT for phase equilibrium calculations. • Determining Kihara potential parameters for hydrate formers. • Successful usage of the model for systems with hydrate azeotropes. - Abstract: In this communication, equilibrium conditions of clathrate hydrates containing mixtures of noble gases (Argon, Krypton and Xenon) and light hydrocarbons (C 1 –C 3 ), which form structure I and II, are modeled. The thermodynamic model is based on the solid solution theory of Van der Waals–Platteeuw combined with the simplified Perturbed-Chain Statistical Association Fluid Theory equation of state (sPC-SAFT EoS). In dispersion term of sPC-SAFT EoS, the temperature dependent binary interaction parameters (k ij ) are adjusted; taking advantage of the well described (vapor + liquid) phase equilibria. Furthermore, the Kihara potential parameters are optimized based on the P–T data of pure hydrate former. Subsequently, these obtained parameters are used to predict the binary gas hydrate dissociation conditions. The equilibrium conditions of the binary gas hydrates predicted by this model agree well with experimental data (overall AAD P ∼ 2.17)

  14. Electronegative gases

    International Nuclear Information System (INIS)

    Christophorou, L.G.

    1981-01-01

    Recent knowledge on electronegative gases essential for the effective control of the number densities of free electrons in electrically stressed gases is highlighted. This knowledge aided the discovery of new gas dielectrics and the tailoring of gas dielectric mixtures. The role of electron attachment in the choice of unitary gas dielectrics or electronegative components in dielectric gas mixtures, and the role of electron scattering at low energies in the choice of buffer gases for such mixtures is outlined

  15. Combined distiller waste utilisation and combustion gases desulphurisation method. The case study of soda-ash industry

    Energy Technology Data Exchange (ETDEWEB)

    Kasikowski, Tomasz; Buczkowski, Roman; Cichosz, Marcin; Lemanowska, Eliza [Faculty of Chemistry, Nicolas Copernicus University, ul. Gagarina 7, 87-100 Torun (Poland)

    2007-09-15

    In this paper, a concept of technology that can be helpful for lowering the negative influence of the synthetic (based on the Solvay process) soda ash plant on the natural environment is presented. We describe the desulphurisation of combustion gases from the factory's power plant, which is based on their absorption in the overflow of distiller waste. The excess of lime milk, which is added in the process of ammonia regeneration from filter liquor, results in a strong alkalinity of distiller waste. The high pH of distiller waste favours absorption of acidic combustion gases. The laboratory-scale tests showed about 80% efficiency of the desulphurisation process. The suspension samples we obtained consist mainly of CaCO{sub 3}. We suggest using the obtained solid phase as an adsorbent-insert in Fluidised Bed Combustion technology (FBC). Based on raw material prices, production costs, and average sell prices of the product, economic analysis of innovation was executed. Profits from employing the method presented come mainly from reduction of environmental fees. The sensitivity analysis of cost showed that the application of the desulphurisation process causes cost reduction in soda-ash production accounting for EUR 150 thousand per year (excluding depreciation) in Poland, and EUR 11,700 thousand per year (excluding depreciation) in Sweden. It has been found that the latter value is similar to the positive environmental impact of this innovation expressed in monetary units (EUR 10,350 thousand per year, excluding depreciation). (author)

  16. Greenhouse Gases

    Science.gov (United States)

    ... also produced by human activities. Some, such as industrial gases, are exclusively human made. What are the types ... Carbon dioxide (CO2) Methane (CH4) Nitrous oxide (N2O) Industrial gases: Hydrofluorocarbons (HFCs) Perfluorocarbons (PFCs) Sulfur hexafluoride (SF6 Nitrogen ...

  17. Three-dimensional vapor intrusion modeling approach that combines wind and stack effects on indoor, atmospheric, and subsurface domains.

    Science.gov (United States)

    Shirazi, Elham; Pennell, Kelly G

    2017-12-13

    Vapor intrusion (IV) exposure risks are difficult to characterize due to the role of atmospheric, building and subsurface processes. This study presents a three-dimensional VI model that extends the common subsurface fate and transport equations to incorporate wind and stack effects on indoor air pressure, building air exchange rate (AER) and indoor contaminant concentration to improve VI exposure risk estimates. The model incorporates three modeling programs: (1) COMSOL Multiphysics to model subsurface fate and transport processes, (2) CFD0 to model atmospheric air flow around the building, and (3) CONTAM to model indoor air quality. The combined VI model predicts AER values, zonal indoor air pressures and zonal indoor air contaminant concentrations as a function of wind speed, wind direction and outdoor and indoor temperature. Steady state modeling results for a single-story building with a basement demonstrate that wind speed, wind direction and opening locations in a building play important roles in changing the AER, indoor air pressure, and indoor air contaminant concentration. Calculated indoor air pressures ranged from approximately -10 Pa to +4 Pa depending on weather conditions and building characteristics. AER values, mass entry rates and indoor air concentrations vary depending on weather conditions and building characteristics. The presented modeling approach can be used to investigate the relationship between building features, AER, building pressures, soil gas concentrations, indoor air concentrations and VI exposure risks.

  18. SAW Sensors for Chemical Vapors and Gases.

    Science.gov (United States)

    Devkota, Jagannath; Ohodnicki, Paul R; Greve, David W

    2017-04-08

    Surface acoustic wave (SAW) technology provides a sensitive platform for sensing chemicals in gaseous and fluidic states with the inherent advantages of passive and wireless operation. In this review, we provide a general overview on the fundamental aspects and some major advances of Rayleigh wave-based SAW sensors in sensing chemicals in a gaseous phase. In particular, we review the progress in general understanding of the SAW chemical sensing mechanism, optimization of the sensor characteristics, and the development of the sensors operational at different conditions. Based on previous publications, we suggest some appropriate sensing approaches for particular applications and identify new opportunities and needs for additional research in this area moving into the future.

  19. Ignitability and explosibility of gases and vapors

    CERN Document Server

    Ma, Tingguang

    2015-01-01

    The book provides a systematic view on flammability and a collection of solved engineering problems in the fields of dilution and purge, mine gas safety, clean burning safety and gas suppression modeling. For the first time, fundamental principles of energy conservation are used to develop theoretical flammability diagrams and are then explored to understand various safety-related mixing problems. This provides the basis for a fully-analytical solution to any flammability problem. Instead of the traditional view that flammability is a fundamental material property, here flammability is discovered to be a result of the explosibility of air and the ignitability of fuel, or a process property. By exploring the more fundamental concepts of explosibility and ignitability, the safety targets of dilution and purge can be better defined and utilized for guiding safe operations in process safety. This book provides various engineering approaches to mixture flammability, benefiting not only the safety students, but al...

  20. SAW Sensors for Chemical Vapors and Gases

    Science.gov (United States)

    Devkota, Jagannath; Ohodnicki, Paul R.; Greve, David W.

    2017-01-01

    Surface acoustic wave (SAW) technology provides a sensitive platform for sensing chemicals in gaseous and fluidic states with the inherent advantages of passive and wireless operation. In this review, we provide a general overview on the fundamental aspects and some major advances of Rayleigh wave-based SAW sensors in sensing chemicals in a gaseous phase. In particular, we review the progress in general understanding of the SAW chemical sensing mechanism, optimization of the sensor characteristics, and the development of the sensors operational at different conditions. Based on previous publications, we suggest some appropriate sensing approaches for particular applications and identify new opportunities and needs for additional research in this area moving into the future. PMID:28397760

  1. Integrated approach for combining sustainability and safety into a RAM analysis, RAM2S (Reliability, Availability, Maintainability, Sustainability and Safety) towards greenhouse gases emission targets

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga, Tobias V. [Det Norske Veritas (DNV), Hovik, Oslo (Norway)

    2009-07-01

    This paper aims to present an approach to integrate sustainability and safety concerns on top of a typical RAM Analysis to support new enterprises to find alternatives to align themselves to the greenhouse gases emission targets, measured as CO{sub 2} (carbon dioxide) equivalent. This approach can be used to measure the impact of the potential CO{sub 2} equivalent emission levels mainly related to new enterprises with high CO{sub 2} content towards environment and production, as per example, the extraction of oil and gas from the Brazilian Pre-salt layers. In this sense, this integrated approach, combining Sustainability and Safety into a RAM analysis, RAM2S (Reliability, Availability, Maintainability, Sustainability and Safety), can be used to assess the impact of CO{sub 2} 'production' along the entire enterprise life-cycle, including the impact of possible facility shutdown due to emission restrictions limits, as well as due to the occurrence of additional failures modes related to CO{sub 2} corrosion capabilities. Thus, at the end, this integrated approach would allow companies to find out a more cost-effective alternative to adapt their business into the global warming reality, overcoming the inherent threats of greenhouse gases. (author)

  2. Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

    NARCIS (Netherlands)

    Wild, de P.J.; Nyqvist, R.G.; Bruijn, de F.A.; Stobbe, E.R.

    2006-01-01

    Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based(e.g. proton exchange membrane fuel cells (PEMFC) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To preventdetrimental effects on the

  3. Modeling vapor-liquid interfaces with the gradient theory in combination with the CPA equation of state

    DEFF Research Database (Denmark)

    Queimada, Antonio; Miqueu, C; Marrucho, IM

    2005-01-01

    and the correct phase equilibrium of water + hydrocarbon systems already obtained from CPA. In this work, preliminary studies involving the vapor-liquid interfacial tensions of some selected associating and non-associating pure components (water, ethanol, n-butane, n-pentane, n-hexane, n-heptane) are presented...

  4. Irritant gases

    NARCIS (Netherlands)

    Meulenbelt, J

    Acute inhalation injury can result from the use of household cleaning agents (e.g. chlorine, ammonia), industrial or combustion gases (e.g. sulfur dioxide, nitrogen oxides) or bioterrorism. The severity of the injury is to a great extent determined by the circumstances of exposure. If exposure was

  5. Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

    Energy Technology Data Exchange (ETDEWEB)

    De Wild, P.J.; Nyqvist, R.G.; De Bruijn, F.A.; Stobbe, E.R. [ECN Hydrogen and Clean Fossil Fuels, Petten (Netherlands)

    2006-02-15

    Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based (e.g. proton exchange membrane fuel cells (PEMFC)) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To prevent detrimental effects on the (electro)catalysts in fuel cell-based combined heat and power installations (FC-CHP), sulphur removal from the feedstock is mandatory. An experimental bench-marking study of adsorbents has identified several candidates for the removal of sulphur containing odorants at low temperature. Among these adsorbents a new material has been discovered that offers an economically attractive means to remove TetraHydroThiophene (THT), the main European odorant, from natural gas at ambient temperature. The material is environmentally benign, easy to use and possesses good activity (residual sulphur levels below 20 ppbv) and capacity for the common odorant THT in natural gas. When compared to state-of-the-art metal-promoted active carbon the new material has a THT uptake capacity that is up to 10 times larger, depending on temperature and pressure. Promoted versions of the new material have shown potential for the removal of THT at higher temperatures and/or for the removal of other odorants such as mercaptans from natural gas or from LPG.

  6. Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

    Energy Technology Data Exchange (ETDEWEB)

    de Wild, P.J.; Nyqvist, R.G.; de Bruijn, F.A.; Stobbe, E.R. [Energy Research Centre of The Netherlands ECN, P.O. Box 1, 1755 ZG Petten (Netherlands)

    2006-09-22

    Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based (e.g. proton exchange membrane fuel cells (PEMFC) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To prevent detrimental effects on the (electro)catalysts in fuel cell-based combined heat and power installations (FC-CHP), sulphur removal from the feedstock is mandatory. An experimental bench-marking study of adsorbents has identified several candidates for the removal of sulphur containing odorants at low temperature. Among these adsorbents a new material has been discovered that offers an economically attractive means to remove TetraHydroThiophene (THT), the main European odorant, from natural gas at ambient temperature. The material is environmentally benign, easy to use and possesses good activity (residual sulphur levels below 20ppbv) and capacity for the common odorant THT in natural gas. When compared to state-of-the-art metal-promoted active carbon the new material has a THT uptake capacity that is up to 10 times larger, depending on temperature and pressure. Promoted versions of the new material have shown potential for the removal of THT at higher temperatures and/or for the removal of other odorants such as mercaptans from natural gas or from LPG. (author)

  7. Noble Gases

    Science.gov (United States)

    Podosek, F. A.

    2003-12-01

    The noble gases are the group of elements - helium, neon, argon, krypton, xenon - in the rightmost column of the periodic table of the elements, those which have "filled" outermost shells of electrons (two for helium, eight for the others). This configuration of electrons results in a neutral atom that has relatively low electron affinity and relatively high ionization energy. In consequence, in most natural circumstances these elements do not form chemical compounds, whence they are called "noble." Similarly, much more so than other elements in most circumstances, they partition strongly into a gas phase (as monatomic gas), so that they are called the "noble gases" (also, "inert gases"). (It should be noted, of course, that there is a sixth noble gas, radon, but all isotopes of radon are radioactive, with maximum half-life a few days, so that radon occurs in nature only because of recent production in the U-Th decay chains. The factors that govern the distribution of radon isotopes are thus quite different from those for the five gases cited. There are interesting stories about radon, but they are very different from those about the first five noble gases, and are thus outside the scope of this chapter.)In the nuclear fires in which the elements are forged, the creation and destruction of a given nuclear species depends on its nuclear properties, not on whether it will have a filled outermost shell when things cool off and nuclei begin to gather electrons. The numerology of nuclear physics is different from that of chemistry, so that in the cosmos at large there is nothing systematically special about the abundances of the noble gases as compared to other elements. We live in a very nonrepresentative part of the cosmos, however. As is discussed elsewhere in this volume, the outstanding generalization about the geo-/cosmochemistry of the terrestrial planets is that at some point thermodynamic conditions dictated phase separation of solids from gases, and that the

  8. Combined cycle simulator with gas turbine and steam turbine with one vaporization stage; Simulador de ciclo combinado con turbina de gas y de vapor con un nivel de vaporizacion

    Energy Technology Data Exchange (ETDEWEB)

    Del Valle Cardenas, B.; Lugo Leyte, R. [Universidad Autonoma Metropolitana, Depto de Ingenieria de Procesos e Hidraulica, Mexico, D. F. (Mexico); Toledo Velazquez, Miguel; Tolentino Eslava, G. [Seccion de Estudios de Posgrado e Investigacion, Laboratorio de Ingenieria Termica e Hidraulica Aplicada, ESIME-IPN-COFFA, Mexico, D. F. (Mexico)

    1998-12-31

    This paper shows the thermal analysis of a combined cycle with gas and steam turbines with one vaporization stage. The analysis is performed through a computer program, which allows the simulation of cycles with different operational conditions, obtaining this way a series of results that permits to know the way these cycles behave in effecting temperature and pressure changes; besides of being an excellent tool in thermodynamics for the user. The simulators were performed in Borland C++ and Builder C++ Versions 4.5 and 2.0 respectively, creating in this way a friendly ambient for the user. This tool offers the opportunity to all its users the ability to simulate combined cycles in a fast and easy way in order to obtain a wider understanding of its thermodynamic behavior. [Espanol] En el presente trabajo se muestra el analisis termico de un ciclo combinado con turbinas de gas y de vapor con un nivel de vaporizacion. El analisis se realiza a traves de un programa de computo, el cual permite simular los ciclos con diferentes condiciones de operacion, obteniendo con esto una serie de resultados que permiten conocer la forma en que trabajan estos ciclos al realizar cambios en temperaturas y presiones; ademas de que es una excelente herramienta para el usuario en termodinamica. Los simuladores fueron realizados en Borland C++ y Builder C++ Versiones 4.5 y 2.0 respectivamente, creandose asi un ambiente amigable para el usuario. Esta herramienta brinda la oportunidad a todos los usuarios de poder simular ciclos combinados de una manera rapida y sencilla con el fin de obtener una comprension mas amplia de su comportamiento termodinamico.

  9. Combined cycle simulator with gas turbine and steam turbine with one vaporization stage; Simulador de ciclo combinado con turbina de gas y de vapor con un nivel de vaporizacion

    Energy Technology Data Exchange (ETDEWEB)

    Del Valle Cardenas, B; Lugo Leyte, R [Universidad Autonoma Metropolitana, Depto de Ingenieria de Procesos e Hidraulica, Mexico, D. F. (Mexico); Toledo Velazquez, Miguel; Tolentino Eslava, G [Seccion de Estudios de Posgrado e Investigacion, Laboratorio de Ingenieria Termica e Hidraulica Aplicada, ESIME-IPN-COFFA, Mexico, D. F. (Mexico)

    1999-12-31

    This paper shows the thermal analysis of a combined cycle with gas and steam turbines with one vaporization stage. The analysis is performed through a computer program, which allows the simulation of cycles with different operational conditions, obtaining this way a series of results that permits to know the way these cycles behave in effecting temperature and pressure changes; besides of being an excellent tool in thermodynamics for the user. The simulators were performed in Borland C++ and Builder C++ Versions 4.5 and 2.0 respectively, creating in this way a friendly ambient for the user. This tool offers the opportunity to all its users the ability to simulate combined cycles in a fast and easy way in order to obtain a wider understanding of its thermodynamic behavior. [Espanol] En el presente trabajo se muestra el analisis termico de un ciclo combinado con turbinas de gas y de vapor con un nivel de vaporizacion. El analisis se realiza a traves de un programa de computo, el cual permite simular los ciclos con diferentes condiciones de operacion, obteniendo con esto una serie de resultados que permiten conocer la forma en que trabajan estos ciclos al realizar cambios en temperaturas y presiones; ademas de que es una excelente herramienta para el usuario en termodinamica. Los simuladores fueron realizados en Borland C++ y Builder C++ Versiones 4.5 y 2.0 respectivamente, creandose asi un ambiente amigable para el usuario. Esta herramienta brinda la oportunidad a todos los usuarios de poder simular ciclos combinados de una manera rapida y sencilla con el fin de obtener una comprension mas amplia de su comportamiento termodinamico.

  10. Investigations into electrical discharges in gases

    CERN Document Server

    Klyarfel'D, B N

    2013-01-01

    Investigations into Electrical Discharges in Gases is a compilation of scientific articles that covers the advances in the investigation of the fundamental processes occurring in electrical discharges in gases and vapors. The book details the different aspects of the whole life cycle of an arc, which include the initiation of a discharge, its transition into an arc, the lateral spread of the arc column, and the recovery of electric strength after extinction of an arc. The text also discusses the methods for the dynamic measurement of vapor density in the vicinity of electrical discharges, alon

  11. Fuel gases

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    This paper gives a brief presentation of the context, perspectives of production, specificities, and the conditions required for the development of NGV (Natural Gas for Vehicle) and LPG-f (Liquefied Petroleum Gas fuel) alternative fuels. After an historical presentation of 80 years of LPG evolution in vehicle fuels, a first part describes the economical and environmental advantages of gaseous alternative fuels (cleaner combustion, longer engines life, reduced noise pollution, greater natural gas reserves, lower political-economical petroleum dependence..). The second part gives a comparative cost and environmental evaluation between the available alternative fuels: bio-fuels, electric power and fuel gases, taking into account the processes and constraints involved in the production of these fuels. (J.S.)

  12. Photoacoustic absorption spectra of atmospheric gases near 7603 cm-1

    International Nuclear Information System (INIS)

    Lawton, S.A.; Bragg, S.L.

    1984-01-01

    Absorption spectra of carbon monoxide, water vapor, memane, and ammonia are presented as part of an effort to determine absolute absorption cross sections for some atmospheric gases at the iodine laser wavelength

  13. Performance analysis of a combined organic Rankine cycle and vapor compression cycle for power and refrigeration cogeneration

    International Nuclear Information System (INIS)

    Kim, Kyoung Hoon; Perez-Blanco, Horacio

    2015-01-01

    A thermodynamic analysis of cogeneration of power and refrigeration activated by low-grade sensible energy is presented in this work. An organic Rankine cycle (ORC) for power production and a vapor compression cycle (VCC) for refrigeration using the same working fluid are linked in the analysis, including the limiting case of cold production without net electricity production. We investigate the effects of key parameters on system performance such as net power production, refrigeration, and thermal and exergy efficiencies. Characteristic indexes proportional to the cost of heat exchangers or of turbines, such as total number of transfer units (NTU tot ), size parameter (SP) and isentropic volumetric flow ratio (VFR) are also examined. Three important system parameters are selected, namely turbine inlet temperature, turbine inlet pressure, and the flow division ratio. The analysis is conducted for several different working fluids. For a few special cases, isobutane is used for a sensitivity analysis due to its relatively high efficiencies. Our results show that the system has the potential to effectively use low grade thermal sources. System performance depends both on the adopted parameters and working fluid. - Highlights: • Waste heat utilization can reduce emissions of carbon dioxide. • The ORC/VCC cycle can deliver power and/or refrigeration using waste heat. • Efficiencies and size parameters are used for cycle evaluation. • The cycle performance is studied for eight suitable refrigerants. Isobutane is used for a sensitivity analysis. • The work shows that the isobutene cycle is quite promising.

  14. Exergy analysis of a combined vapor power cycle and boiler flue gas driven double effect water–LiBr absorption refrigeration system

    International Nuclear Information System (INIS)

    Talukdar, K.; Gogoi, T.K.

    2016-01-01

    Highlights: • A combined vapor power and double effect water–LiBr absorption refrigeration system is proposed. • The flue gas of the power cycle boiler is the heat source for the double effect refrigeration system. • Energy and exergy analyses are performed to evaluate performance of the combined system. • Effect of high pressure generator temperature on combined system performance is highlighted. • Comparison is provided with a single effect absorption system integrated combined system. - Abstract: A combined vapor power cycle (PC) and double effect water–LiBr absorption refrigeration system (ARS) is proposed in this study. The boiler leaving flue gas of the PC is the heat source for the high pressure generator (HPG) of the double effect ARS. Exergy analysis of the proposed system is performed to show the performance variation of both the topping PC and the bottoming ARS with changing HPG temperature from 120 °C to 150 °C. Further the performance of double effect ARS integrated combined power and cooling system is compared with a similar system integrated with a single effect ARS. HPG temperature of the double effect ARS and generator temperature of the single effect ARS are considered as 120 °C and 80 °C respectively. Results show that the power and efficiency of the topping PC decreases with HPG temperature due to reduction in steam generation rate in the boiler. COP and exergy efficiency of the double effect ARS also reduces with increasing HPG temperature. The irreversible losses in the PC components decrease while the total irreversibility of the combined power and cooling system increases with HPG temperature due to increase in exergy loss with the HPG leaving flue gas and irreversibility of the ARS components. PC performance does not vary much due to replacement of the double effect ARS with the single effect ARS, however higher COP and exergy efficiency of the double effect system are achieved with much lower irreversible losses in the

  15. Efficiency of utilization of heat of moisture from exhaust gases of heat HRSG of CCGT

    Directory of Open Access Journals (Sweden)

    Galashov Nikolay

    2017-01-01

    Full Text Available The paper discusses the technology of utilizing the heat of exhaust gas moisture from heat recovery steam gases (HRSG of combined-cycle gas turbine (CCGT. Particular attention focused on the influence of the excess air factor on the trapping of the moisture of the exhaust gases, as in the HRSG of the CCGT its value varies over a wider range than in the steam boilers of the TPP. For the research, has been developed a mathematical model that allows to determine the volumes of combustion products and the amount of water vapor produced according to a given composition of the burned gas and determine the amount of moisture that will be obtained as a result of condensation at a given temperature of the flue gases at the outlet of the condensation heat exchanger (CHE. To calculate the efficiency of the HRSG taking into account the heat of condensation of moisture in the CHE an equation is derived.

  16. Selection of the optimal combination of water vapor absorption lines for detection of temperature in combustion zones of mixing supersonic gas flows by diode laser absorption spectrometry

    International Nuclear Information System (INIS)

    Mironenko, V.R.; Kuritsyn, Yu.A.; Bolshov, M.A.; Liger, V.V.

    2017-01-01

    Determination of a gas medium temperature by diode laser absorption spectrometry (DLAS) is based on the measurement of integral intensities of the absorption lines of a test molecule (generally water vapor molecule). In case of local thermodynamic equilibrium temperature is inferred from the ratio of the integral intensities of two lines with different low energy levels. For the total gas pressure above 1 atm the absorption lines are broadened and one cannot find isolated well resolved water vapor absorption lines within relatively narrow spectral interval of fast diode laser (DL) tuning range (about 3 cm"−"1). For diagnostics of a gas object in the case of high temperature and pressure DLAS technique can be realized with two diode lasers working in different spectral regions with strong absorption lines. In such situation the criteria of the optimal line selection differs significantly from the case of narrow lines. These criteria are discussed in our work. The software for selection the optimal spectral regions using the HITRAN-2012 and HITEMP data bases is developed. The program selects spectral regions of DL tuning, minimizing the error of temperature determination δT/T, basing on the attainable experimental error of line intensity measurement δS. Two combinations of optimal spectral regions were selected – (1.392 & 1.343 μm) and (1.392 & 1.339 μm). Different algorithms of experimental data processing are discussed.

  17. Method and apparatus for removing radioactive gases from a nuclear reactor

    International Nuclear Information System (INIS)

    Frumerman, R.; Brown, W.W.

    1975-01-01

    A description is given of a method for removing radioactive gases from a nuclear reactor including the steps of draining coolant from a nuclear reactor to a level just below the coolant inlet and outlet nozzles to form a vapor space and then charging the space with an inert gas, circulating coolant through the reactor to assist the release of radioactive gases from the coolant into the vapor space, withdrawing the radioactive gases from the vapor space by a vacuum pump which then condenses and separates water from gases carried forward by the vacuum pump, discharging the water to a storage tank and supplying the separated gases to a gas compressor which pumps the gases to gas decay tanks. After the gases in the decay tanks lose their radioactive characteristics, the gases may be discharged to the atmosphere or returned to the reactor for further use

  18. Trace metal analysis in arctic aerosols by an inductively coupled plasma-time of flight-mass spectrometer combined with an inductively heated vaporizer

    International Nuclear Information System (INIS)

    Luedke, Christian; Skole, Jochen; Taubner, Kerstin; Kriews, Michael

    2005-01-01

    Two newly developed instruments were combined to analyze the trace metal content in size separated arctic aerosols during the measurement campaign ASTAR 2004 (Arctic Study of Tropospheric Aerosols, Clouds and Radiation 2004) at Spitsbergen in May-June 2004. The aim of this extensive aerosol measurement campaign was to obtain a database for model-calculations of arctic aerosol, which play an important role in the global climate change. The ASTAR project was centered on two aircraft measurement campaigns, scheduled from 2004 to 2005, addressing both aerosol and cloud measurements, combined with ground-based and satellite observations. In the present paper one example for the analysis of ground-based aerosol particles is described. The sampling of aerosol particles was performed in a well-known manner by impaction of the particles on cleaned graphite targets. By means of a cascade impactor eight size classes between 0.35 and 16.6 μm aerodynamic diameters were separated. To analyze the metal content in the aerosol particles the targets were rapidly heated up to 2700 deg. C in an inductively heated vaporizer system (IHVS). An argon flow transports the vaporized sample material into the inductively coupled plasma (ICP) used as ionization source for the time of flight-mass spectrometer (TOF-MS). The simultaneous extraction of the ions from the plasma, as realized in the TOF instrument, allows to obtain the full mass spectrum of the sample during the vaporization pulse without any limitation in the number of elements detected. With optimized experimental parameters the element content in arctic aerosol particles was determined in a mass range between 7 Li and 209 Bi. Comparing the size distribution of the elemental content of the aerosol particles, two different meteorological situations were verified. For calibration acidified reference solutions were placed on the cleaned target inside the IHVS. The limits of detection (LOD) for the element mass on the target range

  19. GREENHOUSE GASES AND MEANS OF PREVENTION

    Directory of Open Access Journals (Sweden)

    Dušica Stojanović

    2013-09-01

    Full Text Available The greenhouse effect can be defined as the consequence of increased heating of the Earth's surface, as well as the lower atmosphere by carbon dioxide, water vapor, and other trace amounts gases. It is well-known that human industrial activities have released large amounts of greenhouse gases in the atmosphere, about 900 billion tons of carbon dioxide, and it is estimated that up to 450 billion are still in the atmosphere. In comparison to greenhouse gases water vapor is one of the greatest contributors to the greenhouse effect on Earth. Many projects, as does the PURGE project, have tendences to build on the already conducted research and to quantify the positive and negative impacts on health and wellbeing of the population with greenhouse gas reduction strategies that are curently being implemented and should be increasingly applied in various sectors and urban areas, having offices in Europe, China and India.

  20. Management of prostate enlargement with acute urinary retention: Diode laser vaporization in combination with bipolar transurethral resection of the prostate

    Directory of Open Access Journals (Sweden)

    Kai-Yi Tzou

    2016-03-01

    Conclusion: DV + bTURP is comparable with monopolar TURP for relieving acute urinary retention in men with BPE in terms of complications and functional outcomes. The combined technique can provide better intraoperative hemostasis and shorter catheterization time, with no significant postoperative irritative symptoms.

  1. Transport processes in ionized gases

    International Nuclear Information System (INIS)

    Kremer, G.M.

    1997-01-01

    Based on kinetic theory of gases and on the combined of Chapman-Enskog and Grad, the laws of Ohm, Fourier and Navier-Stokes are derived for a non-relativistic fully ionized gas. Moreover, the combined method is applied to the BGK model of the relativistic Boltzmann equation and the Ohm's law is derived for a relativistic fully ionized gas. (author)

  2. Exergy based parametric analysis of a combined reheat regenerative thermal power plant and water–LiBr vapor absorption refrigeration system

    International Nuclear Information System (INIS)

    Gogoi, T.K.; Talukdar, K.

    2014-01-01

    Highlights: • Exergy analysis of a combined power–absorption cooling system is provided. • Exergetic efficiency of the power cycle and absorption cooling system are calculated. • Irreversibility in each component and total system irreversibility are calculated. • Effect of operating parameters on exergetic performance and irreversibility is analyzed. • Optimum operating parameters are identified based on energy and exergy based results. - Abstract: In this paper, exergy analysis of a combined reheat regenerative steam turbine (ST) based power cycle and water–LiBr vapor absorption refrigeration system (VARS) is presented. Exergetic efficiency of the power cycle and VARS, energy utilization factor (EUF) of the combined system (CS) and irreversibility in each system component are calculated. The effect of fuel flow rate, boiler pressure, cooling capacity and VARS components’ temperature on performance, component and total system irreversibility is analyzed. The second law based results indicate optimum performance at 150 bar boiler pressure and VARS generator, condenser, evaporator and absorber temperature of 80 °C, 37.5 °C, 15 °C and 35 °C respectively. The present exergy based results conform well to the first law based results obtained in a previous analysis done on the same combined system. Irreversibility distribution among various power cycle components shows the highest irreversibility in the cooling tower. Irreversibility of the exhaust flue gas leaving the boiler and the boiler are the next major contributors. Among the VARS components, exergy destruction in the generator is the highest followed by irreversibility contribution of the absorber, condenser and the evaporator

  3. Progress report of FY 1999 activities: The application of Kalman filtering to derive water vapor profiles from combined ground-based sensors: Raman lidar, microwave radiometers, GPS, and radiosondes

    International Nuclear Information System (INIS)

    Edgeworth R. Westwater; Yong Han

    1999-01-01

    Previously, the proposers have delivered to ARM a documented algorithm, that is now applied operationally, and which derives water vapor profiles from combined remote sensor measurements of water vapor radiometers, cloud-base ceilometers, and radio acoustic sounding systems (RASS). With the expanded deployment of a Raman lidar at the CART Central Facility, high quality, high vertical-resolution, water vapor profiles will be provided during nighttime clear conditions, and during clear daytime conditions, to somewhat lower altitudes. The object of this effort is to use Kalman Filtering, previously applied to the combination of nighttime Raman lidar and microwave radiometer data, to derive high-quality water vapor profiles, during non-precipitating conditions, from data routinely available at the CART site. Input data to the algorithm would include: Raman lidar data, highly quality-controlled data of integrated moisture from microwave radiometers and GPS, RASS, and radiosondes. While analyzing data obtained during the Water Vapor Intensive Operating Period'97 at the SGP CART site in central Oklahoma, several questions arose about the calibration of the ARM microwave radiometers (MWR). A large portion of this years effort was a thorough analysis of the many factors that are important for the calibration of this instrument through the tip calibration method and the development of algorithms to correct this procedure. An open literature publication describing this analysis has been accepted

  4. COMBINED THEORETICAL AND EXPERIMENTAL INVESTIGATION OF MECHANISMS AND KINETICS OF VAPOR-PHASE MERCURY UPTAKE BY CARBONACEOUS SURFACES; ANNUAL

    International Nuclear Information System (INIS)

    Radisav D. Vidic; Eric V. Borguet; Karl J. Johnson

    2000-01-01

    The overall goal of this research program is to gain fundamental understanding of the important chemistry and physics involved in mercury adsorption on carbonaceous surfaces. This knowledge will then be used to optimize adsorption processes and operating conditions to maximize the uptake of mercury within the required contact time. An additional long-term benefit of this research is the basic understanding of the Hg adsorption process, which may facilitate the design of new adsorbents for more efficient and cost-effective removal of Hg from a variety of effluent streams. Molecular modeling of the adsorption of Hg on carbonaceous surfaces will greatly increase the insight into the physics of the adsorption process and combined with in situ rate measurements of mercury adsorption and desorption (conventional and pulsed laser) on graphite using linear and nonlinear optical probes with real time optical resolution have the potential to provide fundamental insight into the process of mercury uptake by carbonaceous surfaces. Besides accurate assessment of key parameters influencing adsorption equilibrium, fundamental understanding of the kinetics of mercury adsorption, desorption, and diffusion will be developed in this study. These key physical and chemical processes postulated through molecular modeling efforts and verified by in situ measurements will be utilized to select (or develop) promising sorbents for mercury control, which will be tested under dynamic conditions using simulated flue gas

  5. Chemically assisted release of transition metals in graphite vaporizers for atomic spectrometry

    International Nuclear Information System (INIS)

    Katskov, Dmitri; Darangwa, Nicholas; Grotti, Marco

    2006-01-01

    The processes associated with the vaporization of microgram samples and modifiers in a graphite tube ET AAS were investigated by the example of transition metals. The vapor absorption spectra and vaporization behavior of μg-amounts Cd, Zn, Cu, Ag, Au, Ni, Co, Fe, Mn and Cr were studied using the UV spectrometer with CCD detector, coupled with a continuum radiation source. The pyrocoated, Ta or W lined tubes, with Ar or He as internal gases, and filter furnace were employed in the comparative experiments. It was found that the kinetics of atomic vapor release changed depending on the specific metal-substrate-gas combination; fast vaporization at the beginning was followed by slower 'tailing.' The absorption continuum, overlapped by black body radiation at longer wavelengths, accompanied the fast vaporization mode for all metals, except Cd and Zn. The highest intensity of the continuum was observed in the pyrocoated tube with Ar. For Cu and Ag the molecular bands overlapped the absorption continuum; the continuum and bands were suppressed in the filter furnace. It is concluded that the exothermal interaction of sample vapor with the material of the tube causes the energy evolution in the gas phase. The emitted heat is dispersed near the tube wall in the protective gas and partially transferred back to the surface of the sample, thus facilitating the vaporization. The increased vapor flow causes over-saturation and gas-phase condensation in the absorption volume at some distance from the wall, where the gas temperature is not affected by the reaction. The condensation is accompanied by the release of phase transition energy via black body radiation and atomic emission. The particles of condensate and molecular clusters cause the scattering of light and molecular absorption; slow decomposition of the products of the sample vapor-substrate reaction produces the 'tailing' of atomic absorption signal. The interaction of graphite with metal vapor or oxygen, formed in the

  6. Effectiveness of air vapor barriers combined with ventilated crawlspaces in decreasing residential exposure to radon daughters to radon daughters: preliminary report

    International Nuclear Information System (INIS)

    Sterling, T.D.; Arundel, A.; McIntyre, D.; Sterling, E.; Sterling, T.D.

    1986-01-01

    Radon gas is present in many homes. Concentrations may be increased in airtight, energy-efficient structures. This is especially true in cold climates where energy conservation is an important factor leading to the widespread application of sealing and tightening techniques both in older renovated homes and new construction. To reduce radon concentrations, it may be effective to ventilate crawlspaces and prevent infiltration of radon gas into the house by means of an air/vapor barrier. The authors report first results of comparing radon levels in homes with and without ventilated crawlspaces and air/vapor barriers. Radon emissions were measured in a tightly sealed home with ventilated crawlspaces and an air/vapor barrier and in two homes without such vapor barriers and ventilated crawlspaces, but differing in ventilation. Preliminary results suggest that use of ventilated crawlspaces and bottomside vapor barriers may reduce indoor radon levels by approximately 60%. 15 references, 1 table

  7. Trace gases and other potential perturbations to global climate

    International Nuclear Information System (INIS)

    Wang, W.; Wuebbles, D.J.; Washington, W.M.; Isaacs, R.G.; Molnar, G.

    1986-01-01

    We review the various natural and anthropogenic factors that may affect the climate. The purpose is to summarize our understanding of these factors and their potential future climatic effects so that CO 2 -induced climate change can be viewed in a proper context. The factors we discuss include trace gases, anthropogenic and volcanic aerosols, variation of solar constant, change of surface characteristics, and releases of waste heat. We discuss the origins of the various natural and anthropogenic perturbations, the physical and chemical processes and their interactions, model sensitivity calculations, and model projections of their potential future climatic effects. The discussions center on trace gases because of their potentially large climatic effects. It appears that the increases of atmospheric trace gases of other kinds in addition to CO 2 could have important climatic effects. The model calculations suggest that the combined effect of these other trace gases, and the associated change of atmospheric ozone and water vapor distributions, could potentially warm the climate by an amount comparable in magnitude to the effect of doubling the CO 2 . Aerosols of anthropogenic origins may have substantial effects on regional climate, while the volcanic aerosols may have an effect on large-scale climate for up to a few years after injection. Changes of surface characteristics and releases of waste heat may also have substantial effects on the regional climate, but these effects are most likely to be small when compared with the effect of CO 2 increase. Changes of solar constant could have an effect on the global scale, but the time scale is much longer. There is much more that needs to be learned with regard to the above mentioned natural and anthropogenic factors that may affect the climate. A brief summary of those needs is presented

  8. Progress report of FY 1997 activities: The application of Kalman filtering to derive water vapor profiles from combined ground-based sensors: Raman lidar, microwave radiometers, GPS, and radiosondes

    International Nuclear Information System (INIS)

    Edgeworth R. Westwater; Yong Han

    1997-01-01

    Previously, the proposers have delivered to ARM a documented algorithm, that is now applied operationally, and which derives water vapor profiles from combined remote sensor measurements of water vapor radiometers, cloud-base ceilometers, and radio acoustic sounding systems (RASS). With the expanded deployment of a Raman lidar at the CART Central Facility, high quality, high vertical-resolution, water vapor profiles will be provided during nighttime clear conditions, and during clear daytime conditions, to somewhat lower altitudes. The object of this proposal was to use Kalman Filtering, previously applied to the combination of nighttime Raman lidar and microwave radiometer data, to derive high-quality water vapor profiles, during non-precipitating conditions, from data routinely available at the CART site. Input data to the algorithm would include: Raman lidar data, highly quality-controlled data of integrated moisture from microwave radiometers and GPS, RASS, and radiosondes. The algorithm will include recently-developed quality control procedures for radiometers. The focus of this years activities has been on the intercomparison of data obtained during an intensive operating period at the SGP CART site in central Oklahoma

  9. Combined in-situ and ex-situ bioremediation of petroleum hydrocarbon contaminated soils by closed-loop soil vapor extraction and air injection

    International Nuclear Information System (INIS)

    Hu, S.S.; Buckler, M.J.

    1993-01-01

    Treatment and restoration of petroleum hydrocarbon contaminated soils at a bulk petroleum above-ground storage tank (AST) site in Michigan is being conducted through in-situ and ex-situ closed-loop soil vapor extraction (SVE), soil vapor treatment, and treated air injection (AI) processes. The soil vapor extraction process applies a vacuum through the petroleum hydrocarbon affected soils in the ex-situ bio-remediation pile (bio-pile) and along the perimeter of excavated area (in-situ area) to remove the volatile or light petroleum hydrocarbons. This process also draws ambient air into the ex-situ bio-pile and in-situ vadose zone soil along the perimeter of excavated area to enhance biodegradation of light and heavy petroleum hydrocarbons in the soil. The extracted soil vapor is treated using a custom-designed air bio-remediation filter (bio-filter) to degrade the petroleum hydrocarbon compounds in the soil vapor extraction air streams. The treated air is then injected into a flush grade soil bed in the backfill area to perform final polishing of the air stream, and to form a closed-loop air flow with the soil vapor extraction perforated pipes along the perimeter of the excavated area

  10. Development of Natural Gas Fired Combined Cycle Plant for Tri-Generation of Power, Cooling and Clean Water Using Waste Heat Recovery: Techno-Economic Analysis

    OpenAIRE

    Mohan, Gowtham; Dahal, Sujata; Kumar, Uday; Martin, Andrew; Kayal, Hamid

    2014-01-01

    Tri-generation is one of the most efficient ways for maximizing the utilization of available energy. Utilization of waste heat (flue gases) liberated by the Al-Hamra gas turbine power plant is analyzed in this research work for simultaneous production of: (a) electricity by combining steam rankine cycle using heat recovery steam generator (HRSG); (b) clean water by air gap membrane distillation (AGMD) plant; and (c) cooling by single stage vapor absorption chiller (VAC). The flue gases liber...

  11. Ellipsometry-based combination of isothermal sorption-desorption measurement and temperature programmed desorption technique: A probe for interaction of thin polymer films with solvent vapor

    Science.gov (United States)

    Efremov, Mikhail Yu.; Nealey, Paul F.

    2018-05-01

    An environmental chamber equipped with an in situ spectroscopic ellipsometer, programmatic vapor pressure control, and variable temperature substrate holder has been designed for studying polymer coating behavior during an exposure to a solvent vapor and also for probing the residual solvent in the film afterwards. Both sorption-desorption cycle at a constant temperature and temperature programmed desorption (TPD) of the residual solvent manifest themselves as a change of the film thickness. Monitoring of ellipsometric angles of the coating allows us to determine the thickness as a function of the vapor pressure or sample temperature. The solvent vapor pressure is precisely regulated by a computer-controlled pneumatics. TPD spectra are recorded during heating of the film in an oil-free vacuum. The vapor pressure control system is described in detail. The system has been tested on 6-170 nm thick polystyrene, poly(methyl methacrylate), and poly(2-vinyl pyridine) films deposited on silicon substrates. Liquid toluene, water, ethanol, isopropanol, cyclohexane, 1,2-dichloroethane, and chlorobenzene were used to create a vapor atmosphere. Typical sorption-desorption and TPD curves are shown. The instrument achieves sub-monolayer sensitivity for adsorption studies on flat surfaces. Polymer-solvent vapor systems with strong interaction demonstrate characteristic absorption-desorption hysteresis spanning from vacuum to the glass transition pressure. Features on the TPD curves can be classified as either glass transition related film contraction or low temperature broad contraction peak. Typical absorption-desorption and TPD dependencies recorded for the 6 nm thick polystyrene film demonstrate the possibility to apply the presented technique for probing size effects in extremely thin coatings.

  12. Fault diagnosis in the steam turbo-generator of a Combined Cycle Power Plant; Diagnostico de fallas en el turbogenerador a vapor de una central de generacion de ciclo combinado

    Energy Technology Data Exchange (ETDEWEB)

    Flores Abad, Angel

    2006-12-15

    Due to the physical nature of its components, technological processes are vulnerable to faults. These faults affect the accurate behavior of the system, causing a performance reduction, even great economical losses and in the worst case environmental and human disasters. The opportune detection of the presence of faults helps to take corrective actions and as a consequence to reduce the potential damage that faults cause. To achieve the fault detection task, technological processes have supervisory systems to monitor the process variables and provide an alarm when a variable reached a given threshold. This method has the drawback that a single fault could cause many system alarms, which difficult the fault isolation. In addition it is based on hardware redundancy; it means the use of repeated devices to do the same work. Combined cycle power plants (CCPP) are large scale systems with a high degree of fault susceptibility. Due to strict conditions in which they operate and the great number of elements they contain, including sensors and actuators. Nowadays this kind of power plants tends to dominate the electric generation market by means of fossil fuels, because they are the most efficient, profitable, with flexible operation and with less environmental impact. In the CCPP, the steam turbine (ST) is a fundamental component, since it represents the process gain, in the way that it allows the generation of additional electric energy by taking advantage of the exhaust gases of the gas turbines. In case of the ST fails, the global efficiency of the process is reduced even in a 40%. In this work a model based fault diagnosis system was developed, according to the FDI (Fault Detection and Isolation) methodology of the control theory, with the capability of detecting and isolating faults in the sensors and actuators of the ST of a CCPP. The developed system is based on the analytical redundancy which allows optimizing the hardware redundancy and getting a reduction of the

  13. Oil vaporizer

    Energy Technology Data Exchange (ETDEWEB)

    Dumontier, F

    1904-03-31

    An oil burner particularly applicable to heavy oils, composed essentially of one or more gasification chambers, heated by the flame from the burners, to which the combustible gases are fed by the collectors suitably fixed on the chambers, all parts of the apparatus and especially the gasification chambers being easily demountable to permit cleaning, and all arranged in such a manner as to avoid fouling by reducing or localizing the deposition of solid deposits in the coking chamber.

  14. [Gases in vitreoretinal surgery].

    Science.gov (United States)

    Janco, L; Vida, R; Bartos, M; Villémová, K; Izák, M

    2012-02-01

    To evaluate the importance and benefits of using gases in vitreoretinal surgery. The gases represent a wide group of substances used in eye surgery for more than 100 years. The role of intraocular gases in vitreoretinal surgery is irreplaceable. Their use is still considered to be the "gold standard". An important step in eye surgery was the introduction of expanding gases--sulfur hexafluoride and perfluorocarbons into routine clinical practice. The most common indications for the use of intraocular gases are: retinal detachment, idiopathic macular hole, complications of vitreoretinal surgery and others. The introduction of intraocular gases into routine clinical practice, along with other modern surgical techniques resulted in significant improvement of postoperative outcomes in a wide range of eye diseases. Understanding the principles of intraocular gases use brings the benefits to the patient and physician as well. Due to their physical and chemical properties they pose far the best and most appropriate variant of intraocular tamponade. Gases also bring some disadvantages, such as difficulties in detailed fundus examination, visual acuity testing, ultrasonographic examination, difficulties in application of intravitreal drugs or reduced possibility of retina laser treatment. The gases significantly change optical system properties of the eye. The use of gases in vitreoretinal surgery has significantly increased success rate of retinal detachment surgery, complicated posterior segment cases, trauma, surgery of the macula and other diseases.

  15. Mobile vapor recovery and vapor scavenging unit

    International Nuclear Information System (INIS)

    Stokes, C.A.; Steppe, D.E.

    1991-01-01

    This patent describes a mobile anti- pollution apparatus, for the recovery of hydrocarbon emissions. It comprises a mobile platform upon which is mounted a vapor recovery unit for recovering vapors including light hydrocarbons, the vapor recovery unit having an inlet and an outlet end, the inlet end adapted for coupling to an external source of hydrocarbon vapor emissions to recover a portion of the vapors including light hydrocarbons emitted therefrom, and the outlet end adapted for connection to a means for conveying unrecovered vapors to a vapor scavenging unit, the vapor scavenging unit comprising an internal combustion engine adapted for utilizing light hydrocarbon in the unrecovered vapors exiting from the vapor recovery unit as supplemental fuel

  16. A Micro-Preconcentrator Combined Olfactory Sensing System with a Micromechanical Cantilever Sensor for Detecting 2,4-Dinitrotoluene Gas Vapor

    Directory of Open Access Journals (Sweden)

    Myung-Sic Chae

    2015-07-01

    Full Text Available Preventing unexpected explosive attacks and tracing explosion-related molecules require the development of highly sensitive gas-vapor detection systems. For that purpose, a micromechanical cantilever-based olfactory sensing system including a sample preconcentrator was developed to detect 2,4-dinitrotoluene (2,4-DNT, which is a well-known by-product of the explosive molecule trinitrotoluene (TNT and exists in concentrations on the order of parts per billion in the atmosphere at room temperature. A peptide receptor (His-Pro-Asn-Phe-Ser-Lys-Tyr-Ile-Leu-His-Gln-Arg that has high binding affinity for 2,4-DNT was immobilized on the surface of the cantilever sensors to detect 2,4-DNT vapor for highly selective detection. A micro-preconcentrator (µPC was developed using Tenax-TA adsorbent to produce higher concentrations of 2,4-DNT molecules. The preconcentration was achieved via adsorption and thermal desorption phenomena occurring between target molecules and the adsorbent. The µPC directly integrated with a cantilever sensor and enhanced the sensitivity of the cantilever sensor as a pretreatment tool for the target vapor. The response was rapidly saturated within 5 min and sustained for more than 10 min when the concentrated vapor was introduced. By calculating preconcentration factor values, we verified that the cantilever sensor provides up to an eightfold improvement in sensing performance.

  17. Extraction with supercritical gases

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, G M; Wilke, G; Stahl, E

    1980-01-01

    The contents of this book derives from a symposium on the 5th and 6th of June 1978 in the ''Haus der Technik'' in Essen. Contributions were made to separation with supercritical gases, fluid extraction of hops, spices and tobacco, physicochemical principles of extraction, phase equilibria and critical curves of binary ammonia-hydrocarbon mixtures, a quick method for the microanalytical evaluation of the dissolving power of supercritical gases, chromatography with supercritical fluids, the separation of nonvolatile substances by means of compressed gases in countercurrent processes, large-scale industrial plant for extraction with supercritical gases, development and design of plant for high-pressure extraction of natural products.

  18. Handbook of purified gases

    CERN Document Server

    Schoen, Helmut

    2015-01-01

    Technical gases are used in almost every field of industry, science and medicine and also as a means of control by government authorities and institutions and are regarded as indispensable means of assistance. In this complete handbook of purified gases the physical foundations of purified gases and mixtures as well as their manufacturing, purification, analysis, storage, handling and transport are presented in a comprehensive way. This important reference work is accompanied with a large number of Data Sheets dedicated to the most important purified gases.  

  19. Numerical analyses of the effect of a biphasic thermosyphon vapor channel sizes on the heat transfer intensity when heat removing from a power transformer of combined heat and power station

    Directory of Open Access Journals (Sweden)

    Nurpeiis Atlant

    2017-01-01

    Full Text Available Numerical analyses of the effect of a biphasic thermosyphon vapor channel sizes on the heat transfer intensity was conducted when heat removing from an oil tank of a power transformer of combined heat and power station (CHP. The power transformer cooling system by the closed biphasic thermosyphon was proposed. The mathematical modeling of heat transfer and phase transitions of coolant in the thermosyphon was performed. The problem of heat transfer is formulated in dimensionless variables “velocity vorticity vector – current function – temperature” and solved by finite difference method. As a result of numerical simulation it is found that an increase in the vapor channel length from 0.15m to 1m leads to increasing the temperature difference by 3.5 K.

  20. Analytical methods for toxic gases from thermal degradation of polymers

    Science.gov (United States)

    Hsu, M.-T. S.

    1977-01-01

    Toxic gases evolved from the thermal oxidative degradation of synthetic or natural polymers in small laboratory chambers or in large scale fire tests are measured by several different analytical methods. Gas detector tubes are used for fast on-site detection of suspect toxic gases. The infrared spectroscopic method is an excellent qualitative and quantitative analysis for some toxic gases. Permanent gases such as carbon monoxide, carbon dioxide, methane and ethylene, can be quantitatively determined by gas chromatography. Highly toxic and corrosive gases such as nitrogen oxides, hydrogen cyanide, hydrogen fluoride, hydrogen chloride and sulfur dioxide should be passed into a scrubbing solution for subsequent analysis by either specific ion electrodes or spectrophotometric methods. Low-concentration toxic organic vapors can be concentrated in a cold trap and then analyzed by gas chromatography and mass spectrometry. The limitations of different methods are discussed.

  1. Petroleum Vapor Intrusion

    Science.gov (United States)

    One type of vapor intrusion is PVI, in which vapors from petroleum hydrocarbons such as gasoline, diesel, or jet fuel enter a building. Intrusion of contaminant vapors into indoor spaces is of concern.

  2. Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lara-Castells, María Pilar de, E-mail: Pilar.deLara.Castells@csic.es; Bartolomei, Massimiliano [Instituto de Física Fundamental (C.S.I.C.), Serrano 123, E-28006 Madrid (Spain); Mitrushchenkov, Alexander O. [Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée (France); Stoll, Hermann [Institut für Theoretische Chemie, Universität Stuttgart, D-70550 Stuttgart (Germany)

    2015-11-21

    The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = {sup 3}He, {sup 4}He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6–7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the

  3. Vapor and gas sampling of single-shell tank 241-B-102 using the in situ vapor sampling system

    International Nuclear Information System (INIS)

    Lockrem, L.L.

    1997-01-01

    The Vapor Issue Resolution Program tasked the Vapor Team (the team) to collect representative headspace samples from Hanford Site single-shell tank (SST) 241-B-102. This document presents sampling data resulting from the April 18, 1996 sampling of SST 241-B-102. Analytical results will be presented in a separate report issued by Pacific Northwest National Laboratory (PNNL), which supplied and analyzed the sampling media. The team, consisting of Sampling and Mobile Laboratories (SML) and Special Analytical Studies (SAS) personnel, used the vapor sampling system (VSS) to collect representative samples of the air, gases, and vapors from the headspace of SST 241-B-102 with sorbent traps and SUMMA canisters

  4. Assessment of a new method for the analysis of decomposition gases of polymers by a combining thermogravimetric solid-phase extraction and thermal desorption gas chromatography mass spectrometry.

    Science.gov (United States)

    Duemichen, E; Braun, U; Senz, R; Fabian, G; Sturm, H

    2014-08-08

    For analysis of the gaseous thermal decomposition products of polymers, the common techniques are thermogravimetry, combined with Fourier transformed infrared spectroscopy (TGA-FTIR) and mass spectrometry (TGA-MS). These methods offer a simple approach to the decomposition mechanism, especially for small decomposition molecules. Complex spectra of gaseous mixtures are very often hard to identify because of overlapping signals. In this paper a new method is described to adsorb the decomposition products during controlled conditions in TGA on solid-phase extraction (SPE) material: twisters. Subsequently the twisters were analysed with thermal desorption gas chromatography mass spectrometry (TDS-GC-MS), which allows the decomposition products to be separated and identified using an MS library. The thermoplastics polyamide 66 (PA 66) and polybutylene terephthalate (PBT) were used as example polymers. The influence of the sample mass and of the purge gas flow during the decomposition process was investigated in TGA. The advantages and limitations of the method were presented in comparison to the common analysis techniques, TGA-FTIR and TGA-MS. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. The role of moisture on combustion of pyrolysis gases in wildland fires

    Science.gov (United States)

    Selina C. Ferguson; Ambarish Dahale; Babak Shotorban; S. Mahalingam; David R. Weise

    2013-01-01

    The role of water vapor, originated from the moisture content in vegetation, on the combustion process was investigated via simulating an opposed diffusion flame and a laminar premixed flame with pyrolysis gases as the fuel and air as the oxidizer. The fuel was mixed with water vapor, and the simulation was repeated for various water mole fractions. In both of the...

  6. FTIR analysis of flue gases - combined in-situ and dry extractive gas sampling; Kombination av in-situ och kallextraktiv roekgasmaetning med FTIR

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Christer; Soederbom, J [Vattenfall Utveckling AB, Aelvkarleby (Sweden)

    1996-10-01

    Fourier Transform Infra Red (FTIR) spectroscopy is a promising and versatile technique for gas analysis which lately has moved from the laboratory to industrial applications such as emission monitoring of combustion plants. This has been made possible by recent developments of spectrometers and software. The single most important advantage of the FTIR is its capability to simultaneously analyse virtually all gas species of interest in flue gas applications. The project has studied the feasibility of using the technique as a multi-component emission monitoring system. A specific aim was to evaluate different implementations of the technique to flue gas analysis: in-situ, hot/dry and cold extraction or combinations of these. The goal was to demonstrate a system in which gas components that normally require hot extraction (NH{sub 3}, HCl, H{sub 2}O) could instead be measured in-situ. In this way potential sampling artefacts e.g. for ammonia monitoring, can be avoided. The remaining gas components are measured using cold extraction and thereby minimizing interference from water. The latter advantage can be crucial for the accuracy of e.g. NO{sub x} measurements. Prior to the project start in-situ monitoring using FTIR was, a to a large extent, an untried method. The fact that broad band IR radiation can not be guided through optical fibres, presented a major technical obstacle. An `in-situ probe` was developed to serve the purpose. The probe is equipped with a gold plated mirror at the end and is mounted on the support structure of the FTIR-spectrometer. The arrangement proved to be a robust solution without being unnecessary complex or cumbersome to use. 10 refs, 45 figs, 10 tabs

  7. Recondensation phenomena of a hot two-phase fluid in the presence of non condensable gases

    International Nuclear Information System (INIS)

    Berthoud, G.

    1983-09-01

    The condensation rates obtained during the expansion of a large hot bubble containing non condensable gases in its cold liquid is studied. The failure of theories derived from the Nusselt model for liquid metals led to use the kinetic theory of condensation. The additionnal resistance due to the presence of non condensable gases is expressed by the vapor diffusion through the layer of gases which accumulates at the interface. This model is then used to interprete experiments [fr

  8. Kinetic theory of gases

    CERN Document Server

    Kauzmann, Walter

    2012-01-01

    Monograph and text supplement for first-year students of physical chemistry focuses chiefly on the molecular basis of important thermodynamic properties of gases, including pressure, temperature, and thermal energy. 1966 edition.

  9. AC BREAKDOWN IN GASES

    Science.gov (United States)

    electron- emission (multipactor) region, and (3) the low-frequency region. The breakdown mechanism in each of these regions is explained. An extensive bibliography on AC breakdown in gases is included.

  10. Reale Gase, tiefe Temperaturen

    Science.gov (United States)

    Heintze, Joachim

    Wir werden uns in diesem Kapitel zunächst mit der van der Waals'schen Zustandsgleichung befassen. In dieser Gleichung wird versucht, die Abweichungen, die reale Gase vom Verhalten idealer Gase zeigen, durch physikalisch motivierte Korrekturterme zu berücksichtigen. Es zeigt sich, dass die van derWaals-Gleichung geeignet ist, nicht nur die Gasphase, sondern auch die Phänomene bei der Verflüssigung von Gasen und den kritischen Punkt zu beschreiben.

  11. Gases in uranium exploration

    International Nuclear Information System (INIS)

    Wright, R.J.; Pacer, J.C.

    1981-01-01

    Interest continues to grow in the use of helium and radon detection as a uranium exploration tool because, in many instances, these radiogenic gases are the only indicators of deeply buried mineralization. The origin of these gases, their migration in the ground, the type of samples and measurement techniques are discussed. Case histories of comparative tests conducted on known uranium deposits at three geologically diverse sites in the United States of America are also presented. (author)

  12. Transport properties of fission product vapors

    International Nuclear Information System (INIS)

    Im, K.H.; Ahluwalia, R.K.

    1983-07-01

    Kinetic theory of gases is used to calculate the transport properties of fission product vapors in a steam and hydrogen environment. Provided in tabular form is diffusivity of steam and hydrogen, viscosity and thermal conductivity of the gaseous mixture, and diffusivity of cesium iodide, cesium hydroxide, diatomic tellurium and tellurium dioxide. These transport properties are required in determining the thermal-hydraulics of and fission product transport in light water reactors

  13. An exposure system for measuring nasal and lung uptake of vapors in rats

    Energy Technology Data Exchange (ETDEWEB)

    Dahl, A.R.; Brookins, L.K.; Gerde, P. [National Inst. for Working Life, Solna (Sweden)

    1995-12-01

    Inhaled gases and vapors often produce biological damage in the nasal cavity and lower respiratory tract. The specific site within the respirator tract at which a gas or vapor is absorbed strongly influences the tissues at risk to potential toxic effects; to predict or to explain tissue or cell specific toxicity of inhaled gases or vapors, the sites at which they are absorbed must be known. The purpose of the work reported here was to develop a system for determining nose and lung absorption of vapors in rats, an animal commonly used in inhalation toxicity studies. In summary, the exposure system described allows us to measure in the rate: (1) nasal absorption and desorption of vapors; (2) net lung uptake of vapors; and (3) the effects of changed breathing parameters on vapor uptake.

  14. METEOROLOGICAL INFLUENCES ON VAPOR INCIDENTS IN THE 200 EAST and 200 WEST TANK FARMS FROM CY2001 THRU CY2004

    International Nuclear Information System (INIS)

    FAUROTE, J.M.

    2004-01-01

    Investigation into the meteorological influences on vapor incidents in the tank farms to determine what, if any, meteorological influences contribute to the reporting of odors, smells, vapors, and other gases. Weather phenomena, specifically barometric pressure, and wind velocity and direction can potentially cause or exacerbate a vapor release within the farm systems

  15. Production of gaseous or vaporous fuels from solid carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    1951-05-16

    A process for the production of gaseous or vaporous fuels from solid carbonaceous materials consists of subjecting the materials in separate zones to at least three successive thermal treatments at least two of which are carried out at different temperature levels. The materials being maintained in zones in the form of beds of finely divided particles fluidized by the passage of gases or vapors upwardly there-through, and recovering product vapors or gases overhead. The total hot gaseous or vaporous effluent and entrained solids from one of the zones is passed directly without separation to another of the zones situated closely adjacent to and vertically above the first named zone in the same vessel, and the heat required in at least one of the thermal treatment zones is supplied at least in part as the sensible heat of residual solids transferred from a thermal treatment zone operated at a higher temperature.

  16. Molecular model for solubility of gases in flexible polymers

    DEFF Research Database (Denmark)

    Neergaard, Jesper; Hassager, Ole; Szabo, Peter

    1999-01-01

    We propose a model for a priori prediction of the solubility of gases in flexible polymers. The model is based on the concept of ideal solubility of gases in liquids. According to this concept, the mole fraction of gases in liquids is given by Raoult's law with the total pressure and the vapor...... pressure of the gas, where the latter may have to be extrapolated. However, instead of considering each polymer molecule as a rigid structure, we estimate the effective number of degrees of freedom from an equivalent freely jointed bead-rod model for the flexible polymer. In this model, we associate...... the length of the rods with the molecular weight corresponding to a Kuhn step. The model provides a tool for crude estimation of the gas solubility on the basis of only the monomer unit of the polymer and properties of the gas. A comparison with the solubility data for several gases in poly...

  17. Experiences of marijuana-vaporizer users.

    Science.gov (United States)

    Malouff, John M; Rooke, Sally E; Copeland, Jan

    2014-01-01

    Using a marijuana vaporizer may have potential harm-reduction advantages on smoking marijuana, in that the user does not inhale smoke. Little research has been published on use of vaporizers. In the first study of individuals using a vaporizer on their own initiative, 96 adults anonymously answered questions about their experiences with a vaporizer and their use of marijuana with tobacco. Users identified 4 advantages to using a vaporizer over smoking marijuana: perceived health benefits, better taste, no smoke smell, and more effect from the same amount of marijuana. Users identified 2 disadvantages: inconvenience of setup and cleaning and the time it takes to get the device operating for each use. Only 2 individuals combined tobacco in the vaporizer mix, whereas 15 combined tobacco with marijuana when they smoked marijuana. Almost all participants intended to continue using a vaporizer. Vaporizers seem to have appeal to marijuana users, who perceive them as having harm-reduction and other benefits. Vaporizers are worthy of experimental research evaluating health-related effects of using them.

  18. Ciclo combinado Diesel-Vapor como repotenciación de una central termoeléctrica: caso de estudio; Combined Cycle Diesel-Steam as Power Plant Repowering: study case

    Directory of Open Access Journals (Sweden)

    Alberto Eduardo Calvo González

    2015-04-01

    Full Text Available La necesidad imperiosa de cubrir el déficit de generación eléctrica ampliando el potencial de generación con motores diesel a fuel oíl, cuya instalación requiere de muy poco tiempo, es una solución adecuada. La idea de aprovechar los nodos del sistema electro energético, como son las subestaciones y las centrales eléctricas, para instalar los grupos electrógenos es una solución apropiada. Pero en el caso de una central termoeléctrica, al montar estas instalaciones de forma independiente, no se aprovechan las posibilidades que la combinación de procesos ofrece como la disminución del consumo de combustible, y de la contaminación ambiental por unidad de energía producida. El presente trabajo explora la posibilidad de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor. Se demuestra la conveniencia de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor, aprovechando la sinergia que se logra por la combinación de los procesos térmicos.  The pressing need of covering generation deficit to satisfy the demand in the shorter possible time, by enlarging the generation potential with fuel oil fueled diesel motors, it’s an appropriate solution. The idea of taking advantage of electric grid existent nodes facilities to place the generating electricity diesel motors is a non-unwise solution. But in the case of the node of steam power station place these motors in an independent way, don't take advantage of the possibilities that the processes combination offers, as the combined cycle diesel vapor for example. The work presented herein explored and showed the possibility of installing the electric diesel plants as a repowering the existing steam power plant by combined cycle diesel-steam taking advantage of the synergy achieved by thermal processes combination.

  19. Ciclo combinado Diesel-Vapor como repotenciación de una central termoeléctrica: caso de estudio; Combined Cycle Diesel-Steam as Power Plant Repowering: study case

    Directory of Open Access Journals (Sweden)

    Alberto Eduardo Calvo González

    2014-06-01

    Full Text Available La necesidad imperiosa de cubrir el déficit de generación eléctrica ampliando el potencial de generación con motores diesel a fuel oíl, cuya instalación requiere de muy poco tiempo, es una solución adecuada. La idea de aprovechar los nodos del sistema electro energético, como son las subestaciones y las centrales eléctricas, para instalar los grupos electrógenos es una solución apropiada. Pero en el caso de una central termoeléctrica, al montar estas instalaciones de forma independiente, no se aprovechan las posibilidades que la combinación de procesos ofrece como la disminución del consumo de combustible, y de la contaminación ambiental por unidad de energía producida. El presente trabajo explora la posibilidad de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor. Se demuestra la conveniencia de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor, aprovechando la sinergia que se logra por la combinación de los procesos térmicos. The pressing need of covering generation deficit to satisfy the demand in the shorter possible time, by enlarging the generation potential with fuel oil fueled diesel motors, it’s an appropriate solution. The idea of taking advantage of electric grid existent nodes facilities to place the generating electricity diesel motors is a non-unwise solution. But in the case of the node of steam power station place these motors in an independent way, don't take advantage of the possibilities that the processes combination offers, as the combined cycle diesel vapor for example. The work presented herein explored and showed the possibility of installing the electric diesel plants as a repowering the existing steam power plant by combined cycle diesel-steam taking advantage of the synergy achieved by thermal processes combination.

  20. SIMULACIÓN HORARIA DE UN SISTEMA DE REFRIGERACIÓN COMBINADO EYECTOR-COMPRESIÓN DE VAPOR ASISTIDO POR ENERGÍA SOLAR Y GAS NATURAL HOURLY SIMULATION OF A COMBINED EJECTOR-VAPOR COMPRESSION REFRIGERATION SYSTEM ASSISTED BY SOLAR ENERGY AND NATURAL GAS

    Directory of Open Access Journals (Sweden)

    Humberto Vidal

    2009-04-01

    double stage ejector cooling cycle assisted by solar energy system appears as an attractive solution to this problem. The first stage is performed by a mechanical compression cycle with R-134a as the working fluid, while the second stage is performed by a thermally driven ejector cycle with R-141b. Flat plate collectors and an auxiliary energy burner provide heat to the ejector cycle. This paper describes the hourly simulation of a combined ejector-vapor compression refrigeration system assisted by solar energy and natural gas. The combined solar refrigeration system is modeled using the TRNSYS-EES simulation tool and the typical meteorological year data containing the weather data of Florianópolis Brazil. The results obtained from the computational simulation performed in this system show that the combined ejector-vapor compression cooling cycle is more advantageous than the simple ejector cooling cycle. Finally, the computational model developed in this paper might be used to perform a thermo-economical optimization of the system in future works.

  1. Melting temperature, vapor density, and vapor pressure of molybdenum pentafluoride

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Jr, R F; Douglas, T B [National Bureau of Standards, Washington, D.C. (USA). Inst. for Materials Research

    1977-12-01

    A sample of MoF/sub 5/ was prepared by reaction of MoF/sub 6/(g) and Mo(c). Melting curves of temperature against time established the melting temperature at zero impurity to be 318.85 K, the enthalpy of fusion to be 6.1 kJ mol/sup -1/ (+ - 5 per cent), and the cryoscopic impurity of the sample to be 0.15 mole per cent. In the presence of MoF/sub 6/(g) which was added to suppress disproportionation, the vapor density of MoF/sub 5/ over the liquid was measured by the transpiration method at 343, 363, and 383 K, the total MoF/sub 5/ that evaporated being determined by permanganate titration. The total vapor pressure of MoF/sub 5/ oligomers over the liquid was measured by a simple static method at 373 and 392 K, while melting temperatures were taken alternately to monitor possible contamination of the sample. Although the vapor pressures were adjusted for disproportionation, solution of MoF/sub 6/ in MoF/sub 5/ (1), and wall adsorption of MoF/sub 6/ their percentage uncertainty is probably several times that of the vapor densities. A combination of the two properties indicates the average extent of association of the saturated vapor to be near 2, which is the value for the dimer species (MoF/sub 5/)/sub 2/.

  2. Vapor characterization of Tank 241-C-103

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Story, M.S.

    1994-06-01

    The Westinghouse Hanford Company Tank Vapor Issue Resolution Program has developed, in cooperation with Northwest Instrument Systems, Inc., Oak Ridge National Laboratory, Oregon Graduate Institute of Science and Technology, Pacific Northwest Laboratory, and Sandia National Laboratory, the equipment and expertise to characterize gases and vapors in the high-level radioactive waste storage tanks at the Hanford Site in south central Washington State. This capability has been demonstrated by the characterization of the tank 241-C-103 headspace. This tank headspace is the first, and for many reasons is expected to be the most problematic, that will be characterized (Osborne 1992). Results from the most recent and comprehensive sampling event, sample job 7B, are presented for the purpose of providing scientific bases for resolution of vapor issues associated with tank 241-C-103. This report is based on the work of Clauss et al. 1994, Jenkins et al. 1994, Ligotke et al. 1994, Mahon et al. 1994, and Rasmussen and Einfeld 1994. No attempt has been made in this report to evaluate the implications of the data presented, such as the potential impact of headspace gases and vapors to tank farm workers health. That and other issues will be addressed elsewhere. Key to the resolution of worker health issues is the quantitation of compounds of toxicological concern. The Toxicology Review Panel, a panel of Pacific Northwest Laboratory experts in various areas, of toxicology, has chosen 19 previously identified compounds as being of potential toxicological concern. During sample job 7B, the sampling and analytical methodology was validated for this preliminary list of compounds of toxicological concern. Validation was performed according to guidance provided by the Tank Vapor Conference Committee, a group of analytical chemists from academic institutions and national laboratories assembled and commissioned by the Tank Vapor Issue Resolution Program

  3. Vapor characterization of Tank 241-C-103

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Westinghouse Hanford Co., Richland, WA (United States); Story, M.S. [Northwest Instrument Systems, Inc. Richland, WA (United States)

    1994-06-01

    The Westinghouse Hanford Company Tank Vapor Issue Resolution Program has developed, in cooperation with Northwest Instrument Systems, Inc., Oak Ridge National Laboratory, Oregon Graduate Institute of Science and Technology, Pacific Northwest Laboratory, and Sandia National Laboratory, the equipment and expertise to characterize gases and vapors in the high-level radioactive waste storage tanks at the Hanford Site in south central Washington State. This capability has been demonstrated by the characterization of the tank 241-C-103 headspace. This tank headspace is the first, and for many reasons is expected to be the most problematic, that will be characterized (Osborne 1992). Results from the most recent and comprehensive sampling event, sample job 7B, are presented for the purpose of providing scientific bases for resolution of vapor issues associated with tank 241-C-103. This report is based on the work of Clauss et al. 1994, Jenkins et al. 1994, Ligotke et al. 1994, Mahon et al. 1994, and Rasmussen and Einfeld 1994. No attempt has been made in this report to evaluate the implications of the data presented, such as the potential impact of headspace gases and vapors to tank farm workers health. That and other issues will be addressed elsewhere. Key to the resolution of worker health issues is the quantitation of compounds of toxicological concern. The Toxicology Review Panel, a panel of Pacific Northwest Laboratory experts in various areas, of toxicology, has chosen 19 previously identified compounds as being of potential toxicological concern. During sample job 7B, the sampling and analytical methodology was validated for this preliminary list of compounds of toxicological concern. Validation was performed according to guidance provided by the Tank Vapor Conference Committee, a group of analytical chemists from academic institutions and national laboratories assembled and commissioned by the Tank Vapor Issue Resolution Program.

  4. Curiosities of arithmetic gases

    International Nuclear Information System (INIS)

    Bakas, I.; Bowick, M.J.

    1991-01-01

    Statistical mechanical systems with an exponential density of states are considered. The arithmetic analog of parafermions of arbitrary order is constructed and a formula for boson-parafermion equivalence is obtained using properties of the Riemann zeta function. Interactions (nontrivial mixing) among arithmetic gases using the concept of twisted convolutions are also introduced. Examples of exactly solvable models are discussed in detail

  5. Strongly interacting Fermi gases

    Directory of Open Access Journals (Sweden)

    Bakr W.

    2013-08-01

    Full Text Available Strongly interacting gases of ultracold fermions have become an amazingly rich test-bed for many-body theories of fermionic matter. Here we present our recent experiments on these systems. Firstly, we discuss high-precision measurements on the thermodynamics of a strongly interacting Fermi gas across the superfluid transition. The onset of superfluidity is directly observed in the compressibility, the chemical potential, the entropy, and the heat capacity. Our measurements provide benchmarks for current many-body theories on strongly interacting fermions. Secondly, we have studied the evolution of fermion pairing from three to two dimensions in these gases, relating to the physics of layered superconductors. In the presence of p-wave interactions, Fermi gases are predicted to display toplogical superfluidity carrying Majorana edge states. Two possible avenues in this direction are discussed, our creation and direct observation of spin-orbit coupling in Fermi gases and the creation of fermionic molecules of 23Na 40K that will feature strong dipolar interactions in their absolute ground state.

  6. Radiation effects in gases

    International Nuclear Information System (INIS)

    Leonhardt, J.W.

    1985-01-01

    Problems in the studies of radiation effects in gases are discussed. By means of ionization- excitation- and electron-capture yields various applications are characterized: ionization detectors, X-ray detectors, radionuclide battery, and radiation-induced chemical gas-phase reactions. Some new results of basic research in respect to the SO 2 oxidation are discussed. (author)

  7. The greenhouse effect gases

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the greenhouse effect gases. It presents the greenhouses effect as a key component of the climate system, the impacts of the human activity, the foreseeable consequences of global warming, the Kyoto protocol and Total commitment in the domain. (A.L.B.)

  8. Noble gases as cardioprotectants - translatability and mechanism

    NARCIS (Netherlands)

    Smit, Kirsten F.; Weber, Nina C.; Hollmann, Markus W.; Preckel, Benedikt

    2015-01-01

    Several noble gases, although classified as inert substances, exert a tissue-protective effect in different experimental models when applied before organ ischaemia as an early or late preconditioning stimulus, after ischaemia as a post-conditioning stimulus or when given in combination before,

  9. Non-chromatographic speciation analysis of mercury by flow injection on-line preconcentration in combination with chemical vapor generation atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wu Hong [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); Department of Chemistry, Xuzhou Normal University, Xuzhou 221116 (China); Jin Yan [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); Han Weiying [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); Miao, Qiang [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); Bi Shuping [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China)]. E-mail: bisp@nju.edu.cn

    2006-07-15

    A novel non-chromatographic approach for direct speciation of mercury, based on the selective retention inorganic mercury and methylmercury on the inner wall of a knotted reactor by using ammonium diethyl dithiophosphate and dithizone as complexing agents respectively, was developed for flow injection on-line sorption preconcentration coupled with chemical vapor generation non-dispersive atomic fluorescence spectrometry. With the sample pH kept at 2.0, the preconcentration of inorganic mercury on the inner walls of the knotted reactor was carried out based on the exclusive retention of Hg-DDP complex in the presence of methylmercury via on-line merging the sample solution with ammonium diethyl dithiophosphate solution, and selective preconcentration methylmercury was achieved with dithizone instead of ammonium diethyl dithiophosphate. A 15% (v/v) HCl was introduced to elute the retained mercury species and merge with KBH{sub 4} solution for atomic fluorescence spectrometry detection. Under the optimal experimental conditions, the sample throughputs of inorganic mercury and methylmercury were 30 and 20 h{sup -1} with the enhancement factors of 13 and 24. The detection limits were found to be 3.6 ng l{sup -1} for Hg{sup 2+} and 2.0 ng l{sup -1} for CH{sub 3}Hg{sup +}. The precisions (RSD) for the 11 replicate measurements of each 0.2 {mu}g l{sup -1} of Hg{sup 2+} and CH{sub 3}Hg{sup +} were 2.2% and 2.8%, respectively. The developed method was validated by the analysis of certified reference materials (simulated natural water, rice flour and pork) and by recovery measurements on spiked samples, and was applied to the determination of inorganic mercury and methylmercury in biological and environmental water samples.

  10. Non-chromatographic speciation analysis of mercury by flow injection on-line preconcentration in combination with chemical vapor generation atomic fluorescence spectrometry

    International Nuclear Information System (INIS)

    Wu Hong; Jin Yan; Han Weiying; Miao, Qiang; Bi Shuping

    2006-01-01

    A novel non-chromatographic approach for direct speciation of mercury, based on the selective retention inorganic mercury and methylmercury on the inner wall of a knotted reactor by using ammonium diethyl dithiophosphate and dithizone as complexing agents respectively, was developed for flow injection on-line sorption preconcentration coupled with chemical vapor generation non-dispersive atomic fluorescence spectrometry. With the sample pH kept at 2.0, the preconcentration of inorganic mercury on the inner walls of the knotted reactor was carried out based on the exclusive retention of Hg-DDP complex in the presence of methylmercury via on-line merging the sample solution with ammonium diethyl dithiophosphate solution, and selective preconcentration methylmercury was achieved with dithizone instead of ammonium diethyl dithiophosphate. A 15% (v/v) HCl was introduced to elute the retained mercury species and merge with KBH 4 solution for atomic fluorescence spectrometry detection. Under the optimal experimental conditions, the sample throughputs of inorganic mercury and methylmercury were 30 and 20 h -1 with the enhancement factors of 13 and 24. The detection limits were found to be 3.6 ng l -1 for Hg 2+ and 2.0 ng l -1 for CH 3 Hg + . The precisions (RSD) for the 11 replicate measurements of each 0.2 μg l -1 of Hg 2+ and CH 3 Hg + were 2.2% and 2.8%, respectively. The developed method was validated by the analysis of certified reference materials (simulated natural water, rice flour and pork) and by recovery measurements on spiked samples, and was applied to the determination of inorganic mercury and methylmercury in biological and environmental water samples

  11. Influence of absorption by environmental water vapor on radiation transfer in wildland fires

    Science.gov (United States)

    D. Frankman; B. W. Webb; B. W. Butler

    2008-01-01

    The attenuation of radiation transfer from wildland flames to fuel by environmental water vapor is investigated. Emission is tracked from points on an idealized flame to locations along the fuel bed while accounting for absorption by environmental water vapor in the intervening medium. The Spectral Line Weighted-sum-of-gray-gases approach was employed for treating the...

  12. Process of radioactive waste gases

    International Nuclear Information System (INIS)

    Queiser, H.; Schwarz, H.; Schroter, H.J.

    1975-01-01

    A method is described in which the radiation level of waste gases from nuclear power plants containing both activation and fission gases is controlled at or below limits permitted by applicable standards by passing such gases, prior to release to the atmosphere, through an adsorptive delay path including a body of activated carbon having the relation to the throughput and character of such gases. (U.S.)

  13. Robust velocity and load control of a steam turbine in a combined cycle thermoelectric power station; Control robusto de velocidad y carga de una turbina de vapor en una central termoelectrica de ciclo combinado

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Archundia, Enrique

    1998-12-31

    of the computation, the programming languages and the numerical methods allow to develop mathematical models that simulate in an approximate manner the processes to control, as it is the case of the combined cycle thermoelectric power station and in this way making the evaluation of algorithms of modern control possible. In chapter I a functional description of the steam turbine process is given. Since this belongs to a combined cycle thermoelectric power station, it is begun with the description of this power station, later to emphasize the subsystem of the steam turbine and emphasize each one of the elements that comprise this last one. [Espanol] Este trabajo de investigacion esta orientado a disenar, desarrollar y validar un algoritmo de control moderno, que permita la obtencion de mejores desempenos en el control de velocidad de una turbina de vapor perteneciente a una central termoelectrica de ciclo combinado, en todo el intervalo de operacion, asi como la obtencion de mejores desempenos en el control de la cantidad de megawatts generados por la misma cuando esta acoplada a un generador electrico, comparando el desempeno con el obtenido mediante el controlador convencional existente. Los cambios en la referencia de velocidad o carga, son a solicitud del operador y se dan siempre en forma de rampa, indicando la rapidez con la que se desea efectuar el cambio de valor en la referencia. Esta es la razon por la cual el objetivo principal del control a disenar es realizar un buen seguimiento a referencias del tipo rampa. En el subsistema de la turbina de vapor existente el inconveniente de que las valvulas que regulan el flujo de vapor hacia la turbina, presentan un acoplamiento con la valvula del bypass que permite derivar el flujo de vapor hacia el condensador principal sin tener que pasar por la turbina. Es por esto que se propone un control multivariable que contemple la interaccion que se presenta entre las valvulas antes mencionadas, partiendo de un diseno

  14. Bose-Einstein condensation of atomic gases

    International Nuclear Information System (INIS)

    Anglin, J. R.; Ketterle, W.

    2003-01-01

    The early experiments on Bose-Einstein condensation in dilute atomic gases accomplished three longstanding goals. First, cooling of neutral atoms into their motional state, thus subjecting them to ultimate control, limited only by Heisenberg uncertainty relation. Second, creation of a coherent sample of atoms, in which all occupy the same quantum states, and the realization of atom lasers - devices that output coherent matter waves. And third, creation of gaseous quantum fluid, with properties that are different from the quantum liquids helium-3 and helium-4. The field of Bose-Einstein condensation of atomic gases has continued to progress rapidly, driven by the combination of new experimental techniques and theoretical advances. The family of quantum degenerate gases has grown, and now includes metastable and fermionic atoms. condensates have become an ultralow-temperature laboratory for atom optics, collisional physics and many-body physics, encompassing phonons, superfluidity, quantized vortices, Josephson junctions and quantum phase transitions. (author)

  15. Fuel gases in Algeria

    International Nuclear Information System (INIS)

    Arachiche, B.; Elandaloussi, H.

    1996-01-01

    For a country like Algeria, fuel gases represent an important economical challenge. To answer the increasing energy demand in the transportation sector, the use of fuel gases allows to preserve the petroleum reserves and to create specific industrial structures devoted to LPG-f (liquefied petroleum gas-fuel) and NGV (natural gas for vehicles). This paper presents the energy policy of Algeria, its reserves, production, and exportations of hydrocarbons and the internal rational use of energy sources according to its economic and environmental policy and to its internal needs. The energy consumption of Algeria in the transportation sector represents 2/3 of the petroleum products consumed in the internal market and follows a rapid increase necessary to the socio-economic development of the country. The Algerian experience in fuel gases is analysed according to the results of two successive experimentation periods for the development of NGV before and after 1994, and the resulting transportation and distribution network is described. The development of LPG-f has followed also an experimental phase for the preparation of regulation texts and a first statement of the vehicles conversion to LPG-f is drawn with its perspectives of development according to future market and prices evolutions. (J.S.)

  16. The chemical vapor deposition of zirconium carbide onto ceramic substrates

    International Nuclear Information System (INIS)

    Glass A, John Jr.; Palmisiano, Nick Jr.; Welsh R, Edward

    1999-01-01

    Zirconium carbide is an attractive ceramic material due to its unique properties such as high melting point, good thermal conductivity, and chemical resistance. The controlled preparation of zirconium carbide films of superstoichiometric, stoichiometric, and substoichiometric compositions has been achieved utilizing zirconium tetrachloride and methane precursor gases in an atmospheric pressure high temperature chemical vapor deposition system

  17. Effect of adding Te to layered GaSe crystals to increase the van der Waals bonding force

    Science.gov (United States)

    Tanabe, Tadao; Zhao, Shu; Sato, Yohei; Oyama, Yutaka

    2017-10-01

    The interplanar binding strength of layered GaSe1-xTex crystals was directly measured using a tensile testing machine. The GaSe1-xTex crystals were grown by a low temperature liquid phase solution method under a controlled Se vapor pressure. The stoichiometry-controlled GaSe1-xTex crystal has the ɛ-polytype structure of GaSe, where the Te atoms are substituted for some of the Se atoms in the GaSe crystal. The effect of adding Te on the bonding strength between the GaSe layers was determined from direct measurements of the van der Waals bonding energy. The bonding energy was increased from 0.023 × 106 N/m2 for GaSe to 0.16 × 106 N/m2 for GaSe1-xTex (x = 0.106).

  18. Method of start-up operation of a liquefaction and distillation apparatus for processing waste gases containing radioactive rare gases

    International Nuclear Information System (INIS)

    Ota, Masakazu; Tani, Akira; Hashimoto, Hiroshi; An, Bunzai; Kanazawa, Toshio.

    1975-01-01

    Object: To enable reduction of cooling time, simplification of maintenance, and release of cooling gas outside system. Structure: In starting of the liquefaction and distillation apparatus, liquid nitrogen is introduced into the tower bottom of a rectification tower from a liquid nitrogen tank through a liquid nitrogen supply line to vaporize the liquid nitrogen with help of heat entered from outside and a heater. The vaporized nitrogen gas moves up while cooling the interior of the rectification tower and is guided by a vacuum pump from the top of tower toward the purifying gas line and low temperature heat exchanger and disharging into atmosphere. When the interior of the apparatus is sufficiently cooled in a manner as described above, the liquid nitrogen supply line is closed, the liquid nitrogen is fed to a condenser, and the waste gases containing the radioactive rare gases from the raw exhaust supply line are introduced into the rectification tower for entry of normal operation. (Kamimura, M.)

  19. Comparative study of the vapor analytes of trinitrotoluene (TNT)

    Science.gov (United States)

    Edge, Cindy C.; Gibb, Julie; Dugan, Regina E.

    1998-12-01

    Trinitrotoluene (TNT) is a high explosive used in most antipersonnel and antitank landmines. The Institute for Biological Detection Systems (IBDS) has developed a quantitative vapor delivery system, termed olfactometer, for conducting canine olfactory research. The research is conducted utilizing dynamic conditions, therefore, it is imperative to evaluate the headspace of TNT to ensure consistency with the dynamic generation of vapor. This study quantified the vapor headspace of military- grade TNT utilizing two different vapor generated methodologies, static and dynamic, reflecting differences between field and laboratory environments. Static vapor collection, which closely mimics conditions found during field detection, is defined as vapor collected in an open-air environment at ambient temperature. Dynamic vapor collection incorporates trapping of gases from a high flow vapor generation cell used during olfactometer operation. Analysis of samples collected by the two methodologies was performed by gas chromatography/mass spectrometry and the results provided information with regard to the constituents detected. However, constituent concentration did vary between the sampling methods. This study provides essential information regarding the vapor constituents associated with the TNT sampled using different sampling methods. These differences may be important in determining the detection signature dogs use to recognize TNT.

  20. Emissions of exhaust gases and health of the person

    Science.gov (United States)

    Germanova, Tatiana; Kernozhitskaya, Anna

    2017-10-01

    The auto-road complex brings the considerable contribution to pollution and adverse change of environment. Influence of exhaust gases of cars is at the bottom of occurrence and developments of various forms of diseases. Every townsman feels the negative influence rendered by motor transport on himself. The modern city dweller is so accustomed to the smell of exhaust gases that he does not even notice it at all, continues to breathe a poisonous mixture, while neither the car nor the road can be isolated from the habitats of people. The higher the population density, the higher the need for motor transport. The health effects of emissions of exhaust gases and vapors, including regulated and unregulated pollutants, are discussed in this article.

  1. New Regenerative Cycle for Vapor Compression Refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Mark J. Bergander

    2005-08-29

    The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and

  2. On Classical Ideal Gases

    Directory of Open Access Journals (Sweden)

    Laurent Chusseau

    2013-02-01

    Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.

  3. Removing radioactive noble gases from nuclear process off-gases

    International Nuclear Information System (INIS)

    Lofredo, A.

    1977-01-01

    A system is claimed for separating, concentrating and storing radioactive krypton and xenon in the off-gases from a boiling water reactor, wherein adsorption and cryogenic distillation are both efficiently used for rapid and positive separation and removal of the radioactive noble gases, and for limiting such gases in circulation in the system to low inventory at all times, and wherein the system is self-regulating to eliminate operator options or attention

  4. Fuel vapor pressure (FVAPRS)

    International Nuclear Information System (INIS)

    Mason, R.E.

    1979-04-01

    A subcode (FVAPRS) is described which calculates fuel vapor pressure. This subcode was developed as part of the fuel rod behavior modeling task performed at EG and G Idaho, Inc. The fuel vapor pressure subcode (FVAPRS), is presented and a discussion of literature data, steady state and transient fuel vapor pressure equations and estimates of the standard error of estimate to be expected with the FVAPRS subcode are included

  5. Application of Evaporative Cooling for the Condensation of Water Vapors from a Flue Gas Waste Heat Boilers CCP

    Directory of Open Access Journals (Sweden)

    Galashov Nikolay

    2016-01-01

    Full Text Available The object of the study are boilers that burn organic fuel and the recovery boilers (RB of the combined cycle plant (CCP, which are al-so working on the products of the combustion of hydrocarbon fuels. The purpose of research is to find technologies that increase efficiency of the thermal power plant (TPP and technologies that reduce the environmental impact on the environment by burning fossil fuels. The paper deals with the technology of the boilers burning hydrocarbon fuel with condensation of water vapor from the exhaust flue gases. Considered the problems caused by using of this technology. Research shows that the main problem of this technology in the boilers is the lack of reliable methods of calculation of heat exchangers, condensers. Particular attention is paid to the application of this technology in the recovery boilers combined-cycle plants, which are currently gaining increasing use in the generation of electricity from the combustion of gas in power plants. It is shown that the application of technology of condensation of water vapor in RB CCP, the temperature decreases of exhaust gases from 100 to 40 °С, allows increasing the effi-ciency of the RB with 86.2 % to 99.5 %, i.e. at 12.3 %, and increase the ef-ficiency of the CCP at 2.8 %.

  6. Origins of geothermal gases at Yellowstone

    Science.gov (United States)

    Lowenstern, Jacob B.; Bergfeld, Deborah; Evans, William C.; Hunt, Andrew G.

    2015-01-01

    Gas emissions at the Yellowstone Plateau Volcanic Field (YPVF) reflect open-system mixing of gas species originating from diverse rock types, magmas, and crustal fluids, all combined in varying proportions at different thermal areas. Gases are not necessarily in chemical equilibrium with the waters through which they vent, especially in acid sulfate terrain where bubbles stream through stagnant acid water. Gases in adjacent thermal areas often can be differentiated by isotopic and gas ratios, and cannot be tied to one another solely by shallow processes such as boiling-induced fractionation of a parent liquid. Instead, they inherit unique gas ratios (e.g., CH4/He) from the dominant rock reservoirs where they originate, some of which underlie the Quaternary volcanic rocks. Steam/gas ratios (essentially H2O/CO2) of Yellowstone fumaroles correlate with Ar/He and N2/CO2, strongly suggesting that H2O/CO2 is controlled by addition of steam boiled from water rich in atmospheric gases. Moreover, H2O/CO2 varies systematically with geographic location, such that boiling is more enhanced in some areas than others. The δ13C and 3He/CO2 of gases reflect a dominant mantle origin for CO2 in Yellowstone gas. The mantle signature is most evident at Mud Volcano, which hosts gases with the lowest H2O/CO2, lowest CH4 concentrations and highest He isotope ratios (~16Ra), consistent with either a young subsurface intrusion or less input of crustal and meteoric gas than any other location at Yellowstone. Across the YPVF, He isotope ratios (3He/4He) inversely vary with He concentrations, and reflect varied amounts of long- stored, radiogenic He added to the magmatic endmember within the crust. Similarly, addition of CH4 from organic-rich sediments is common in the eastern thermal areas at Yellowstone. Overall, Yellowstone gases reflect addition of deep, high-temperature magmatic gas (CO2-rich), lower-temperatures crustal gases (4He- and CH4-bearing), and those gases (N2, Ne, Ar) added

  7. Paschen's law studies in cold gases

    OpenAIRE

    Massarczyk, R.; Chu, P.; Elliott, S. R.; Rielage, K.; Dugger, C.; Xu, W.

    2016-01-01

    The break-through voltage over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. The breakthrough behavior of the fill gas in colder environments was tested as well. A significant shift of the curve relative to the results at room temperature was observed. The results can be explained by combining Paschen's law and the ideal gas law.

  8. Paschen's law studies in cold gases

    Science.gov (United States)

    Massarczyk, R.; Chu, P.; Dugger, C.; Elliott, S. R.; Rielage, K.; Xu, W.

    2017-06-01

    The break-through voltage behavior over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. At lower temperatures, a significant shift of the curve relative to the results at room temperature was observed. This behavior can be explained by combining Paschen's law and the ideal gas law.

  9. Paschen's law studies in cold gases

    International Nuclear Information System (INIS)

    Massarczyk, R.; Chu, P.; Elliott, S.R.; Rielage, K.; Xu, W.; Dugger, C.

    2017-01-01

    The break-through voltage behavior over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. At lower temperatures, a significant shift of the curve relative to the results at room temperature was observed. This behavior can be explained by combining Paschen's law and the ideal gas law.

  10. Selective noble gases monitoring

    International Nuclear Information System (INIS)

    Janecka, S.; Jancik, O.; Kapisovsky, V.; Kubik, I.; Sevecka, S.

    1995-01-01

    The monitoring of leak releases from ventilation stack of NPP requires a system by several orders more sensitive then currently used radiometer Kalina, designed to cover the range up to a design-based accident. To reach this goal a noble gases monitor with a germanium detector (MPVG) has been developed. It enables nuclide selective monitoring of current value of volume activity of particular nuclides in ventilation stack and daily releases of noble gases (balancing). MPVG can be viewed as a system build of three levels of subsystem: measuring level; control level; presentation level. Measuring level consists of gamma-spectroscopy system and operational parameters monitoring unit (flow rate, temperature, humidity). Control level provides communication between presentation and measuring level, acquisition of operational parameters and power supply. The presentation level of MPVG enables: 1) the measured data storage in predetermined time intervals; 2) the presentation of measured and evaluated values of radiation characteristics. The monitored radionuclides - default set: argon-41, krypton-85m, krypton-87, krypton-88, krypton-89, xenon-131m, xenon-133, xenon-133m, xenon-135, xenon-135m, xenon-137 and xenon-138. The values of volume activities observed at maximum releases have been approximately ten times higher. In that case in balancing some other nuclides exceed corresponding detection limits: 88 Kr(67; 22) Bq/m 3 ; 85m Kr(17; 7) Bq/m 3 ; 135m Xe(7.1; 0.5) Bq/m 3 ; 138 Xe(5.9; 0.9) Bq/m 3 . (J.K.)

  11. Selective noble gases monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Janecka, S; Jancik, O; Kapisovsky, V; Kubik, I; Sevecka, S [Nuclear Power Plants Research Institute, a.s., Trnava (Slovakia)

    1996-12-31

    The monitoring of leak releases from ventilation stack of NPP requires a system by several orders more sensitive then currently used radiometer Kalina, designed to cover the range up to a design-based accident. To reach this goal a noble gases monitor with a germanium detector (MPVG) has been developed. It enables nuclide selective monitoring of current value of volume activity of particular nuclides in ventilation stack and daily releases of noble gases (balancing). MPVG can be viewed as a system build of three levels of subsystem: measuring level; control level; presentation level. Measuring level consists of gamma-spectroscopy system and operational parameters monitoring unit (flow rate, temperature, humidity). Control level provides communication between presentation and measuring level, acquisition of operational parameters and power supply. The presentation level of MPVG enables: 1) the measured data storage in predetermined time intervals; 2) the presentation of measured and evaluated values of radiation characteristics. The monitored radionuclides - default set: argon-41, krypton-85m, krypton-87, krypton-88, krypton-89, xenon-131m, xenon-133, xenon-133m, xenon-135, xenon-135m, xenon-137 and xenon-138. The values of volume activities observed at maximum releases have been approximately ten times higher. In that case in balancing some other nuclides exceed corresponding detection limits: {sup 88}Kr(67; 22) Bq/m{sup 3}; {sup 85m}Kr(17; 7) Bq/m{sup 3}; {sup 135m}Xe(7.1; 0.5) Bq/m{sup 3}; {sup 138}Xe(5.9; 0.9) Bq/m{sup 3}. (J.K.).

  12. High-quality nonpolar a-plane GaN epitaxial films grown on r-plane sapphire substrates by the combination of pulsed laser deposition and metal–organic chemical vapor deposition

    Science.gov (United States)

    Yang, Weijia; Zhang, Zichen; Wang, Wenliang; Zheng, Yulin; Wang, Haiyan; Li, Guoqiang

    2018-05-01

    High-quality a-plane GaN epitaxial films have been grown on r-plane sapphire substrates by the combination of pulsed laser deposition (PLD) and metal–organic chemical vapor deposition (MOCVD). PLD is employed to epitaxial growth of a-plane GaN templates on r-plane sapphire substrates, and then MOCVD is used. The nonpolar a-plane GaN epitaxial films with relatively small thickness (2.9 µm) show high quality, with the full-width at half-maximum values of GaN(11\\bar{2}0) along [1\\bar{1}00] direction and GaN(10\\bar{1}1) of 0.11 and 0.30°, and a root-mean-square surface roughness of 1.7 nm. This result is equivalent to the quality of the films grown by MOCVD with a thickness of 10 µm. This work provides a new and effective approach for achieving high-quality nonpolar a-plane GaN epitaxial films on r-plane sapphire substrates.

  13. Physical model for vaporization

    OpenAIRE

    Garai, Jozsef

    2006-01-01

    Based on two assumptions, the surface layer is flexible, and the internal energy of the latent heat of vaporization is completely utilized by the atoms for overcoming on the surface resistance of the liquid, the enthalpy of vaporization was calculated for 45 elements. The theoretical values were tested against experiments with positive result.

  14. Petroleum Vapor - Field Technical

    Science.gov (United States)

    The screening approach being developed by EPA OUST to evaluate petroleum vapor intrusion (PVI) requires information that has not be routinely collected in the past at vapor intrusion sites. What is the best way to collect this data? What are the relevant data quality issues and ...

  15. Overview of the physical-chemical properties of the noble gases

    International Nuclear Information System (INIS)

    McKinley, C.

    1973-01-01

    This paper lists the concentrations of noble gases in the atmosphere and the relative abundance of the stable isotopes. Selected physical properties are tabulated; solubilities of noble gases in water and other liquids, and liquid-vapor equilibria data for binary systems containing a noble gas are presented. Adsorption data are tabulated for illustrative conventional adsorbents and are also presented by a Polanyi correlation. Clathration, biochemical effects, and chemical reactivity are highlighted. Analytical procedures are briefly described. Other relatively non-reactive gases present in the atmosphere in trace quantities are mentioned: methane, carbon tetrafluoride, and sulfur hexafluoride.

  16. A theoretical study of the growth of large sodium vapor bubbles in liquid sodium, including the effect of noncondensables and of vapor convection

    International Nuclear Information System (INIS)

    Casadei, F.; Donne, M.D.

    1983-01-01

    The study of the dynamics of the expansion of large bubbles of hot sodium vapor in a pool of liquid sodium plays an important role in understanding the effects of a hypothetical core disruptive accident. A model of the growth of the bubble in the pool is described. The equations of the motion of the liquid and of the nonsteady heat diffusion problem are solved together with the continuity and energy equations for the vapor phase. The first set of calculations has been performed with constant evaporation and condensation coefficients. In the second set, however, due account has been taken of the effect on condensation of noncondensable fission gases and vapor convection. Due to the very high calculated vapor velocities, noncondensable gases have little effect on the condensation rate, and the percentage amount of condensed sodium is considerably higher than previously calculated by other authors

  17. Process for scavenging hydrogen sulfide from hydrocarbon gases

    International Nuclear Information System (INIS)

    Fox, I.

    1981-01-01

    A process for scavenging hydrogen sulfide from hydrocarbon gases utilizes iron oxide particles of unique chemical and physical properties. These particles have large surface area, and are comprised substantially of amorphous Fe 2 O 3 containing a crystalline phase of Fe 2 O 3 , Fe 3 O 4 and combinations thereof. In scavenging hydrogen sulfide, the iron oxide particles are suspended in a liquid which enters into intimate mixing contact with hydrocarbon gases; the hydrogen sulfide is reacted at an exceptional rate and only acid-stable reaction products are formed. Thereafter, the sweetened hydrocarbon gases are collected

  18. Piezoelectric trace vapor calibrator

    International Nuclear Information System (INIS)

    Verkouteren, R. Michael; Gillen, Greg; Taylor, David W.

    2006-01-01

    The design and performance of a vapor generator for calibration and testing of trace chemical sensors are described. The device utilizes piezoelectric ink-jet nozzles to dispense and vaporize precisely known amounts of analyte solutions as monodisperse droplets onto a hot ceramic surface, where the generated vapors are mixed with air before exiting the device. Injected droplets are monitored by microscope with strobed illumination, and the reproducibility of droplet volumes is optimized by adjustment of piezoelectric wave form parameters. Complete vaporization of the droplets occurs only across a 10 deg. C window within the transition boiling regime of the solvent, and the minimum and maximum rates of trace analyte that may be injected and evaporated are determined by thermodynamic principles and empirical observations of droplet formation and stability. By varying solution concentrations, droplet injection rates, air flow, and the number of active nozzles, the system is designed to deliver--on demand--continuous vapor concentrations across more than six orders of magnitude (nominally 290 fg/l to 1.05 μg/l). Vapor pulses containing femtogram to microgram quantities of analyte may also be generated. Calibrated ranges of three explosive vapors at ng/l levels were generated by the device and directly measured by ion mobility spectrometry (IMS). These data demonstrate expected linear trends within the limited working range of the IMS detector and also exhibit subtle nonlinear behavior from the IMS measurement process

  19. Improvements to vapor generators

    International Nuclear Information System (INIS)

    Keller, Arthur; Monroe, Neil.

    1976-01-01

    A supporting system is proposed for vapor generators of the 'supported' type. Said supporting system is intended to compensate the disparities of thermal expansion due to the differences in the vertical dimensions of the tubes in the walls of the combustion chamber and their collectors compared to that of the balloon tanks and the connecting tube clusters of vaporization, the first one being longer than the second ones. Said system makes it possible to build said combustion chamber higher than the balloon tanks and the tube clusters of vaporization. The capacity of steam production is thus enhanced [fr

  20. Techniques for the generation and monitoring of vapors

    International Nuclear Information System (INIS)

    Nelson, G.O.

    1981-01-01

    Controlled test atmospheres can be produced using a variety of techniques. Gases are usually generated by using flow dilution methods while vapors are produced by using solvent injection and vaporization, saturation, permeation and diffusion techniques. The resulting gas mixtures can be monitored and measured using flame ionization, photoionization, electrochemical and infrared analytical systems. An ideal system for the production of controlled test atmospheres would not only be able to generate controlled test atmospheres, but also monitor all pertinent environmental parameters, such as temperature, humidity, and air flow

  1. Some approximations for the wet and dry removal of particles and gases from the atmosphere

    Science.gov (United States)

    W. G. N. Slinn

    1976-01-01

    Semi-empirical formulae are presented which can be used to estimate precipitation scavenging and dry deposition of particles and gases. The precipitation scavenging formulae are appropriate both for in- and below-cloud scavenging and comparisons with data indicate the importance of accounting for aerosol particle growth by water vapor condensation and attachment of the...

  2. Canonical partition functions: ideal quantum gases, interacting classical gases, and interacting quantum gases

    Science.gov (United States)

    Zhou, Chi-Chun; Dai, Wu-Sheng

    2018-02-01

    In statistical mechanics, for a system with a fixed number of particles, e.g. a finite-size system, strictly speaking, the thermodynamic quantity needs to be calculated in the canonical ensemble. Nevertheless, the calculation of the canonical partition function is difficult. In this paper, based on the mathematical theory of the symmetric function, we suggest a method for the calculation of the canonical partition function of ideal quantum gases, including ideal Bose, Fermi, and Gentile gases. Moreover, we express the canonical partition functions of interacting classical and quantum gases given by the classical and quantum cluster expansion methods in terms of the Bell polynomial in mathematics. The virial coefficients of ideal Bose, Fermi, and Gentile gases are calculated from the exact canonical partition function. The virial coefficients of interacting classical and quantum gases are calculated from the canonical partition function by using the expansion of the Bell polynomial, rather than calculated from the grand canonical potential.

  3. Microwave assisted chemical vapor infiltration

    International Nuclear Information System (INIS)

    Devlin, D.J.; Currier, R.P.; Barbero, R.S.; Espinoza, B.F.; Elliott, N.

    1991-01-01

    A microwave assisted process for production of continuous fiber reinforced ceramic matrix composites is described. A simple apparatus combining a chemical vapor infiltration reactor with a conventional 700 W multimode oven is described. Microwave induced inverted thermal gradients are exploited with the ultimate goal of reducing processing times on complex shapes. Thermal gradients in stacks of SiC (Nicalon) cloths have been measured using optical thermometry. Initial results on the ''inside out'' deposition of SiC via decomposition of methyltrichlorosilane in hydrogen are presented. Several key processing issues are identified and discussed. 5 refs

  4. Gasoline Reid Vapor Pressure

    Science.gov (United States)

    EPA regulates the vapor pressure of gasoline sold at retail stations during the summer ozone season to reduce evaporative emissions from gasoline that contribute to ground-level ozone and diminish the effects of ozone-related health problems.

  5. Economic Hazardous Gases Management for SOX Removal from Flue Gases

    International Nuclear Information System (INIS)

    Isaack, S.L.; Mohi, M.A.; Mohamed, S.T.

    1995-01-01

    Hazardous gases emerging from industries accumulate as pollutants in air and falls as acid rains resulting also in water and soil pollution. To minimize environmental pollution, the present process is suggested in order to desulfurize flue gases resulting from burning fuel oil in a 100/MWh steam power plant. The process makes use of the cheap Ca C O 3 powder as the alkaline material to sequistre the sulphur oxide gases. The resulting sulphur compounds, namely calcium sulphate and gypsum have a great market demand as reducing and sulphiting agents in paper industry and as an important building material. About 44000 ton of gypsum could be produced yearly when treating flue gases resulting from a 100 MWh unit burning fuel oil. Feasibility study shows that a great return on investment could be achieved when applying the process. 1 fig

  6. Avalanches in insulating gases

    International Nuclear Information System (INIS)

    Verhaart, H.F.A.

    1982-01-01

    Avalanches of charged particles in gases are often studied with the ''electrical method'', the measurement of the waveform of the current in the external circuit. In this thesis a substantial improvement of the time resolution of the measuring setup, to be used for the electrical method, is reported. The avalanche is started by an N 2 -laser with a pulse duration of only 0.6 ns. With this laser it is possible to release a high number of primary electrons (some 10 8 ) which makes it possible to obtain sizeable signals, even at low E/p values. With the setup it is possible to analyze current waveforms with a time resolution down to 1.4 ns, determined by both the laser and the measuring system. Furthermore it is possible to distinguish between the current caused by the electrons and the current caused by the ions in the avalanche and to monitor these currents simultaneously. Avalanche currents are measured in N 2 , CO 2 , O 2 , H 2 O, air of varying humidity, SF 6 and SF 6 /N 2 mixtures. Depending on the nature of the gas and the experimental conditions, processes as diffusion, ionization, attachment, detachment, conversion and secondary emission are observed. Values of parameters with which these processes can be described, are derived from an analysis of the current waveforms. For this analysis already published theories and new theories described in this thesis are used. The drift velocity of both the electrons and the ions could be easily determined from measured avalanche currents. Special attention is paid to avalanches in air becasue of the practical importance of air insulation. (Auth.)

  7. Noble gases solubility in water

    International Nuclear Information System (INIS)

    Crovetto, Rosa; Fernandez Prini, Roberto.

    1980-07-01

    The available experimental data of solubility of noble gases in water for temperatures smaller than 330 0 C have been critically surveyed. Due to the unique structure of the solvent, the solubility of noble gases in water decreases with temperature passing through a temperature of minimum solubility which is different for each gas, and then increases at higher temperatures. As aresult of the analysis of the experimental data and of the features of the solute-solvent interaction, a generalized equation is proposed which enables thecalculation of Henry's coefficient at different temperatures for all noble gases. (author) [es

  8. R-22 vapor explosions

    International Nuclear Information System (INIS)

    Anderson, R.P.; Armstrong, D.R.

    1977-01-01

    Previous experimental and theoretical studies of R-22 vapor explosions are reviewed. Results from two experimental investigations of vapor explosions in a medium scale R-22/water system are reported. Measurements following the drop of an unrestrained mass of R-22 into a water tank demonstrated the existence of two types of interaction behavior. Release of a constrained mass of R-22 beneath the surface of a water tank improved the visual resolution of the system thus allowing identification of two interaction mechansims: at low water temperatures, R-22/water contact would produce immediate violent boiling; at high water temperatures a vapor film formed around its R-22 as it was released, explosions were generated by a surface wave which initiated at a single location and propagated along the vapor film as a shock wave. A new vapor explosion model is proposed, it suggests explosions are the result of a sequence of three independent steps: an initial mixing phase, a trigger and growth phase, and a mature phase where a propagating shock wave accelerates the two liquids into a collapsing vapor layer causing a high velocity impact which finely fragments and intermixes the two liquids

  9. Nanostructure Engineered Chemical Sensors for Hazardous Gas and Vapor Detection

    Science.gov (United States)

    Li, Jing; Lu, Yijiang

    2005-01-01

    A nanosensor technology has been developed using nanostructures, such as single walled carbon nanotubes (SWNTs) and metal oxides nanowires or nanobelts, on a pair of interdigitated electrodes (IDE) processed with a silicon based microfabrication and micromachining technique. The IDE fingers were fabricated using thin film metallization techniques. Both in-situ growth of nanostructure materials and casting of the nanostructure dispersions were used to make chemical sensing devices. These sensors have been exposed to hazardous gases and vapors, such as acetone, benzene, chlorine, and ammonia in the concentration range of ppm to ppb at room temperature. The electronic molecular sensing in our sensor platform can be understood by electron modulation between the nanostructure engineered device and gas molecules. As a result of the electron modulation, the conductance of nanodevice will change. Due to the large surface area, low surface energy barrier and high thermal and mechanical stability, nanostructured chemical sensors potentially can offer higher sensitivity, lower power consumption and better robustness than the state-of-the-art systems, which make them more attractive for defense and space applications. Combined with MEMS technology, light weight and compact size sensors can be made in wafer scale with low cost.

  10. Quotation systems for greenhouse gases

    International Nuclear Information System (INIS)

    Trong, Maj Dang

    2000-01-01

    The article surveys recommendations from a Norwegian committee for implementing at a national level, the Kyoto protocol aims for reducing the total emissions of greenhouse gases from the industrial countries through quotation systems

  11. Physical Vapor Deposition of Thin Films

    Science.gov (United States)

    Mahan, John E.

    2000-01-01

    A unified treatment of the theories, data, and technologies underlying physical vapor deposition methods With electronic, optical, and magnetic coating technologies increasingly dominating manufacturing in the high-tech industries, there is a growing need for expertise in physical vapor deposition of thin films. This important new work provides researchers and engineers in this field with the information they need to tackle thin film processes in the real world. Presenting a cohesive, thoroughly developed treatment of both fundamental and applied topics, Physical Vapor Deposition of Thin Films incorporates many critical results from across the literature as it imparts a working knowledge of a variety of present-day techniques. Numerous worked examples, extensive references, and more than 100 illustrations and photographs accompany coverage of: * Thermal evaporation, sputtering, and pulsed laser deposition techniques * Key theories and phenomena, including the kinetic theory of gases, adsorption and condensation, high-vacuum pumping dynamics, and sputtering discharges * Trends in sputter yield data and a new simplified collisional model of sputter yield for pure element targets * Quantitative models for film deposition rate, thickness profiles, and thermalization of the sputtered beam

  12. Electrospun Polymer Fiber Lasers for Applications in Vapor Sensing

    DEFF Research Database (Denmark)

    Krämmer, Sarah; Laye, Fabrice; Friedrich, Felix

    2017-01-01

    of the narrow lasing modes upon uptake of alcohol vapors (model vapors are methanol and ethanol) serves as sensor signal. Thus, the high sensitivity related to the spectral line shifts of cavity-based transducers can be combined with the fiber's large surface to volume ratio. The resulting optical sensors...

  13. Process for gasifying fuels with the recovery of rich gases

    Energy Technology Data Exchange (ETDEWEB)

    Jahns, F

    1921-04-10

    A process for gasifying fuels with recovery of water-free, rich-in-tar gases in a ring-gas-producer characterized by hot-gas-stream arising from the gasification bed of a fresh chamber in the known way is divided. One part is conducted through an old chamber, the other part is led first during the drying through the fresh fuel and with the received water-vapor also through the old chamber and then during the carbonization with the carbonization products is led to the carbonization-gas conduit.

  14. Greenhouse gases and global warming

    International Nuclear Information System (INIS)

    1995-01-01

    From previous articles we have learned about the complexities of our environment, its atmosphere and its climate system. we have also learned that climate change and, therefore global warm and cool periods are naturally occurring phenomena. Moreover, all scientific evidence suggests that global warming, are likely to occur again naturally in the future. However, we have not yet considered the role of the rates of climate change in affecting the biosphere. It appears that how quickly the climate changes may be more important than the change itself. In light of this concern, let us now consider the possibility that, is due to human activity. We may over the next century experience global warming at rates and magnitudes unparalleled in recent geologic history. The following questions are answered; What can we learn from past climates? What do we know about global climates over the past 100 years? What causes temperature change? What are the greenhouse gases? How much have concentration of greenhouse gases increased in recent years? Why are increases in concentrations of greenhouse of concern? What is the e nhanced greenhouse effect ? How can human activity impact the global climate? What are some reasons for increased concentrations of greenhouse gases? What are fossil fuel and how do they transform into greenhouse gases? Who are the biggest emitters of greenhouse gases? Why are canada per capita emissions of greenhouse gases relatively high? (Author)

  15. A Geochemical Approach for Monitoring a CO2 Pilot Site: Rousse, France. A Major gases, CO2-Carbon Isotopes and Noble Gases Combined Approach Une méthode géochimique pour la surveillance d’un site pilote de stockage de CO2 : Rousse, France. Approche combinant les gaz majeurs, l’isotopie du carbone du CO2 et les gaz rares

    Directory of Open Access Journals (Sweden)

    Garcia B.

    2012-02-01

    Full Text Available This paper presents the geochemical characterization of various gas end-members involved in a depleted gas field CO2 storage pilot (Rousse, France. In this pilot, CO2 is produced by oxycombustion from natural gas transformed into fuel gas at the Lacq plant, and transported in a pipeline 30 km away to the depleted gas reservoir of Rousse. Gases produced at Rousse before CO2 injection, the Lacq fuel gas and the CO2 resulting from the oxy-fuel combustion were sampled, together with gases from a –45 m monitoring well and from soils in the vicinity of the Rousse structure. For all samples, the bulk gas composition, the carbon isotopic compositions and the abundance and isotopic signatures of the noble gases were determined. The bulk gas compositions of the Rousse natural gas are comparable to the Lacq fuel gas with methane as the main compound with residual C2-C5 and CO2. Soil gases are typical mixtures of air with biogenic CO2 (up to 9-10%, while the monitoring well gases display typical air compositions with no excess CO2 The Rousse gas and the Lacq fuel gas have δ13CCH4 values of –41.0‰ and –43.0‰ respectively. The injected CO2 out of the oxycombustion chamber has a δ13CCO2 of –40.0‰, whereas δ13CCO2 value for soils samples is comprised between –15 and –25‰. The Rousse natural gas and the Lacq fuel gas are both characterized by a high He enrichment, and depletion in Ne, Ar and Kr compared to the air values. The oxyfuel combustion process provides a CO2 with the He enrichment of the Lacq fuel gas, and a Ne, Ar and Kr composition reflecting that of the oxygen produced at the Air Separation Unit (ASU. Indeed, Ne is depleted relatively to the air, while Kr is enriched up to tenfold, which results from the cryogenic separation of the air noble gases within the ASU. Soil samples noble gas compositions are equivalent to that of the air. In the light of these results, the compositions of the various end-members involved in this CO2

  16. Tank vapor characterization project - headspace vapor characterization of Hanford Waste Tank 241-C-107: Second comparison study results from samples collected on 3/26/96

    International Nuclear Information System (INIS)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of waste storage tank 241-C-107 (Tank C-107) at the Hanford Site in Washington State. The results described in this report is the second in a series comparing vapor sampling of the tank headspace using the Vapor Sampling System (VSS) and In Situ Vapor Sampling (ISVS) system without high efficiency particulate air (HEPA) prefiltration. The results include air concentrations of water (H 2 O) and ammonia (NH 3 ), permanent gases, total non-methane organic compounds (TO-12), and individual organic analytes collected in SUMMA trademark canisters and on triple sorbent traps (TSTs). Samples were collected by Westinghouse Hanford Company (WHC) and analyzed by Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volume measurements provided by WHC

  17. Tank vapor characterization project. Headspace vapor characterization of Hanford waste tank 241-BY-108: Second comparison study results from samples collected on 3/28/96

    International Nuclear Information System (INIS)

    Thomas, B.L.; Pool, K.H.; Evans, J.C.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of waste storage tank 241-BY-108 (Tank BY-108) at the Hanford Site in Washington State. The results described in this report is the second in a series comparing vapor sampling of the tank headspace using the Vapor Sampling System (VSS) and In Situ Vapor Sampling (ISVS) system without high efficiency particulate air (HEPA) prefiltration. The results include air concentrations of water (H 2 O) and ammonia (NH 3 ), permanent gases, total non-methane organic compounds (TO-12), and individual organic analytes collected in SUMMA trademark canisters and on triple sorbent traps (TSTs). Samples were collected by Westinghouse Hanford Company (WHC) and analyzed by Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volume measurements provided by WHC

  18. Tank Vapor Characterization Project: Annual status report for FY 1996

    International Nuclear Information System (INIS)

    Silvers, K.L.; Fruchter, J.S.; Huckaby, J.L.; Almeida, T.L.; Evans, J.C. Jr.; Pool, K.H.; Simonen, C.A.; Thornton, B.M.

    1997-01-01

    In Fiscal Year 1996, staff at the Vapor Analytical Laboratory at Pacific Northwest National Laboratory performed work in support of characterizing the vapor composition of the headspaces of radioactive waste tanks at the Hanford Site. Work performed included support for technical issues and sampling methodologies, upgrades for analytical equipment, analytical method development, preparation of unexposed samples, analyses of tank headspaces samples, preparation of data reports, and operation of the tank vapor database. Progress made in FY 1996 included completion and issuance of 50 analytical data reports. A sampling system comparison study was initiated and completed during the fiscal year. The comparison study involved the vapor sampling system (VSS), a truck-based system, and the in situ vapor sampling system (ISVS), a cart-based system. Samples collected during the study were characterized for inorganic, permanent gases, total non-methane organic compounds and organic speciation by SUMMA trademark and TST methods. The study showed comparable sampling results between the systems resulting in the program switching from the VSS to the less expensive ISVS methodology in late May 1996. A temporal study was initiated in January 1996 in order to understand the influences seasonal temperatures changes have on the vapors in the headspace of Hanford waste tanks. A holding time study was initiated in the fourth quarter of FY 1996. Samples were collected from tank S-102 and rushed to the laboratory for time zero analysis. Additional samples will be analyzed at 1, 2, 4, 8, 16, and 32 weeks

  19. Vapor pressures and enthalpies of vaporization of azides

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Emel'yanenko, Vladimir N.; Algarra, Manuel; Manuel Lopez-Romero, J.; Aguiar, Fabio; Enrique Rodriguez-Borges, J.; Esteves da Silva, Joaquim C.G.

    2011-01-01

    Highlights: → We prepared and measured vapor pressures and vaporization enthalpies of 7 azides. → We examined consistency of new and available in the literature data. → Data for geminal azides and azido-alkanes selected for thermochemical calculations. - Abstract: Vapor pressures of some azides have been determined by the transpiration method. The molar enthalpies of vaporization Δ l g H m of these compounds were derived from the temperature dependencies of vapor pressures. The measured data sets were successfully checked for internal consistency by comparison with vaporization enthalpies of similarly structured compounds.

  20. The vapor pressure and enthalpy of vaporization of M-xylene

    Energy Technology Data Exchange (ETDEWEB)

    Rothenberg, S J; Seiler, F A; Bechtold, W E; Eidson, A F

    1988-12-01

    We measured the vapor pressure of m-xylene over the temperature range 273 to 293 deg K with a single-sided capacitance manometer. The enthalpy of vaporization was 42.2 {+-} 0.1 (SE) kj/ g{center_dot}mol. Combining our own data with previously published data, we recommend using the values 42.0, 40.6, and 39.1 ({+-} 0.1) (SE) kjg{center_dot}mol for the enthalpy of vaporization of m-xylene at 300, 340, and 380 deg. K, respectively, and a value for the change in heat capacity on vaporization ({delta}Cpdeg.) of 35 {+-} 3 (SE) J/g{center_dot}mol{center_dot}K over the temperature range studied. (author)

  1. The vapor pressure and enthalpy of vaporization of M-xylene

    International Nuclear Information System (INIS)

    Rothenberg, S.J.; Seiler, F.A.; Bechtold, W.E.; Eidson, A.F.

    1988-01-01

    We measured the vapor pressure of m-xylene over the temperature range 273 to 293 deg K with a single-sided capacitance manometer. The enthalpy of vaporization was 42.2 ± 0.1 (SE) kj/ g·mol. Combining our own data with previously published data, we recommend using the values 42.0, 40.6, and 39.1 (± 0.1) (SE) kjg·mol for the enthalpy of vaporization of m-xylene at 300, 340, and 380 deg. K, respectively, and a value for the change in heat capacity on vaporization (ΔCpdeg.) of 35 ± 3 (SE) J/g·mol·K over the temperature range studied. (author)

  2. Radioactive gases monitor system: tritium, radon, noble gases

    International Nuclear Information System (INIS)

    Egey, J.Z.; Matatagui, E.

    2015-01-01

    A system for monitoring the radioactive gases tritium, radon and noble gases is described. We present the description of the sensor and the associated electronics that have been developed to monitor the presence of radioactive gases in air or other gaseous effluents. The system has a high sensitivity and a wide range of operation. The sensor is an ionization chamber, featuring the internal circulation of the gas to monitor and the associated electronics has a resolution better than 10 E-15A (fA). It allows the detection of the individual pulses that are produced during the alpha decay of radon and its daughter elements. The measurement system is made up of a commercial data acquisition system connected to a computer. The acquired data is presented on a graphical display and it is stored for later processing and analysis. We have a system that is of simple construction and versatile. Here we present the experimental results. (authors) [es

  3. METEOROLOGICAL INFLUENCES ON VAPOR INCIDENTS IN THE 200 EAST and 200 WEST TANK FARMS FROM CY1995 TO CY2004

    International Nuclear Information System (INIS)

    HOCKING, M.J.

    2005-01-01

    Revised for a more comprehensive overview of vapor incidents reported at the Hanford Tank Farms. Investigation into the meteorological influences on vapor incidents in the tank farm to determine what, if any, meteorological influences contribute to the reporting of odors, smells, vapors, and other gases. Weather phenomena, specifically barometric pressure, and wind velocity and direction can potentially cause or exacerbate a vapor release within the farm systems. The purpose of this document is to gather and evaluate the meteorological and weather information for the Tank Farms Shift Log Vapor Incident entries and determine what, if any, meteorological influences contribute to the reporting of odors, smells, vapors, and other gases such as propane. A part of the evaluation will be determining which of the incidents are related to actual ''intrusive'' work, and which are ''transient.'' Transient vapor incidents are herein defined as those vapors encountered during walkdowns, surveys, or other activities that did not require working directly with the tanks, pits, transfer lines, etc. Another part of the investigation will involve determining if there are barometric pressures or other weather related phenomena that might cause or contribute vapors being released when there are no ''intrusive'' activities. A final purpose is to evaluate whether there is any correlation between the 242-A Evaporator operations and Vapor Incidents entered on the Shift Log

  4. METEOROLOGICAL INFLUENCES ON VAPOR INCIDENTS IN THE 200 EAST & 200 WEST TANK FARMS FROM CY1995 TO CY2004

    Energy Technology Data Exchange (ETDEWEB)

    HOCKING, M.J.

    2005-01-31

    Revised for a more comprehensive overview of vapor incidents reported at the Hanford Tank Farms. Investigation into the meteorological influences on vapor incidents in the tank farm to determine what, if any, meteorological influences contribute to the reporting of odors, smells, vapors, and other gases. Weather phenomena, specifically barometric pressure, and wind velocity and direction can potentially cause or exacerbate a vapor release within the farm systems. The purpose of this document is to gather and evaluate the meteorological and weather information for the Tank Farms Shift Log Vapor Incident entries and determine what, if any, meteorological influences contribute to the reporting of odors, smells, vapors, and other gases such as propane. A part of the evaluation will be determining which of the incidents are related to actual ''intrusive'' work, and which are ''transient.'' Transient vapor incidents are herein defined as those vapors encountered during walkdowns, surveys, or other activities that did not require working directly with the tanks, pits, transfer lines, etc. Another part of the investigation will involve determining if there are barometric pressures or other weather related phenomena that might cause or contribute vapors being released when there are no ''intrusive'' activities. A final purpose is to evaluate whether there is any correlation between the 242-A Evaporator operations and Vapor Incidents entered on the Shift Log.

  5. Gases and carbon in metals

    International Nuclear Information System (INIS)

    Jehn, H.; Fromm, E.; Hoerz, G.

    1978-01-01

    This issue is part of a series of data on 'gases and carbon in metals'. The present survey includes results from papers dealing with gases and carbon in actinides and recommends critically selected data for each element. Firstly data od binary systems are presented, starting with hydrogen and followed by carbon, nitrogen, oxygen, and rare gases. Within one metal-metalloid system the data are listed under topics such as solubility limit, dissociation pressure of compunds, vapour pressure of volatile oxides, thermodynamic data, diffusion, transport parameters (effective valence, heat of transport), permeation of gases through metals, gas adsorption and gas desorption kinetics, compound formation, precipitation kinetics, and property changes. Following the data on binary systems, the data of ternary systems are presented, beginning with systems which contain one metal and two gases or one gas and carbon and continuing with systems with two metals and one gas or carbon. Within a ternary system the topics are arranged in the same way as in binary systems. (HB) [de

  6. Numerical modelling of multiphase liquid-vapor-gas flows with interfaces and cavitation

    Science.gov (United States)

    Pelanti, Marica

    2017-11-01

    We are interested in the simulation of multiphase flows where the dynamical appearance of vapor cavities and evaporation fronts in a liquid is coupled to the dynamics of a third non-condensable gaseous phase. We describe these flows by a single-velocity three-phase compressible flow model composed of the phasic mass and total energy equations, the volume fraction equations, and the mixture momentum equation. The model includes stiff mechanical and thermal relaxation source terms for all the phases, and chemical relaxation terms to describe mass transfer between the liquid and vapor phases of the species that may undergo transition. The flow equations are solved by a mixture-energy-consistent finite volume wave propagation scheme, combined with simple and robust procedures for the treatment of the stiff relaxation terms. An analytical study of the characteristic wave speeds of the hierarchy of relaxed models associated to the parent model system is also presented. We show several numerical experiments, including two-dimensional simulations of underwater explosive phenomena where highly pressurized gases trigger cavitation processes close to a rigid surface or to a free surface. This work was supported by the French Government Grant DGA N. 2012.60.0011.00.470.75.01, and partially by the Norwegian Grant RCN N. 234126/E30.

  7. Nozzle flow calculation for real gases

    International Nuclear Information System (INIS)

    Bier, K.; Ehrler, F.; Hartz, U.; Kissau, G.

    1977-01-01

    The flow of CHF 2 Cl vapor (refrigerant R 22) through a Laval nozzle of annular geometry has been investigated in the region near the saturation line with stagnation pressures up to 85 per cent of the critical pressure. Static pressure profiles measured along the nozzle axis were found in good agreement with profiles calculated for one-dimensional isentropic flow of the real gas the thermal properties of which were derived from an equation of state proposed previously by Rombusch. Minor deviations between measured and calculated static pressure curves occur in the supersonic part of the mozzle, especially when supersaturated states of the vapour are passed. These deviations can be attributed to uncertainties in the calculation of the enthalpy and to a small influence of the static pressure probe. An additional investigation was concerned with an approximate calculation of the nozzle flow of real gases. In this approximation the well known relations of ideal gas dynamics are applied, the ratio of specific heats for the ideal gas being replaced, however, by a suitably adapted isentropic exponent, which can be determined e.g. from measured values of the Laval pressure or of the mass flow. For pressure ratios p/po between 1 and approximately 0.1, corresponding to Mach numbers up to approximately 2.2, all the interesting properties of the investigated flow of CHF 2 Cl vapour are approximated within a few per cent. (orig.) [de

  8. Desulphurization of exhaust gases in chemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Asperger, K.; Wischnewski, W.

    1981-01-01

    The sulfur content of exhaust gases can be reduced by: desulphurization of fuels; modification of processes; or treatment of resultant gases. In this paper a few selected examples from the chemical industry in the German Democratic Republic are presented. Using modified processes and treating the resultant gases, the sulphuric content of exhaust gases is effectively reduced. Methods to reduce the sulfur content of exhaust gases are described in the field of production of: sulphuric acid; viscose; fertilizers; and paraffin.

  9. Electron thermalization in rare gases and their mixtures

    International Nuclear Information System (INIS)

    Bronic, I.K.; Kimura, M.

    1996-01-01

    The time evolution and temperature dependence of electron energy distribution functions (EDFs) are studied in pure rare gases (He, Ne, Ar, Kr, Xe) as well as in their mixtures by using solutions of the Boltzmann equation. A clear difference between the gases having the Ramsauer endash Townsend (RT) minimum in the momentum-transfer cross section, (RT gases: Ar, Kr, and Xe), and those without the RT minimum (non-RT gases: He and Ne) is pointed out. The influence of the position and the depth of the RT minimum on the EDF and time evolution is studied for three different initial electron energies. A formula proposed for describing thermalization time in a mixture is tested on (i) a non-RT endash non-RT gas mixture, (ii) a RT endash non-RT mixture and (iii) a RT endash RT gas mixture. The linear combination of the reciprocal thermalization times in gas mixture with the component concentrations as weighting factors is found to be valid for gases with a similar energy dependence of the momentum-transfer cross section, σ m , and also for all rare-gas binary mixtures if the initial electron energy is sufficiently below the RT minimum. Conspicuous deviations from the linear relationship are observed in mixtures of gases whose energy dependence of σ m (or the stopping cross section) are different, and theoretical rationales for these findings are provided. copyright 1996 American Institute of Physics

  10. Vaporization of irradiated droplets

    International Nuclear Information System (INIS)

    Armstrong, R.L.; O'Rourke, P.J.; Zardecki, A.

    1986-01-01

    The vaporization of a spherically symmetric liquid droplet subject to a high-intensity laser flux is investigated on the basis of a hydrodynamic description of the system composed of the vapor and ambient gas. In the limit of the convective vaporization, the boundary conditions at the fluid--gas interface are formulated by using the notion of a Knudsen layer in which translational equilibrium is established. This leads to approximate jump conditions at the interface. For homogeneous energy deposition, the hydrodynamic equations are solved numerically with the aid of the CON1D computer code (''CON1D: A computer program for calculating spherically symmetric droplet combustion,'' Los Alamos National Laboratory Report No. LA-10269-MS, December, 1984), based on the implict continuous--fluid Eulerian (ICE) [J. Comput. Phys. 8, 197 (1971)] and arbitrary Lagrangian--Eulerian (ALE) [J. Comput. Phys. 14, 1227 (1974)] numerical mehtods. The solutions exhibit the existence of two shock waves propagating in opposite directions with respect to the contact discontinuity surface that separates the ambient gas and vapor

  11. Vapor liquid fraction determination

    International Nuclear Information System (INIS)

    1980-01-01

    This invention describes a method of measuring liquid and vapor fractions in a non-homogeneous fluid flowing through an elongate conduit, such as may be required with boiling water, non-boiling turbulent flows, fluidized bed experiments, water-gas mixing analysis, and nuclear plant cooling. (UK)

  12. Heat of vaporization spectrometer

    International Nuclear Information System (INIS)

    Edwards, D. Jr.

    1978-01-01

    Multilayer desorption measurements of various substances adsorbed on a stainless steel substrate are found to exhibit desorption profiles consistent with a zeroth order desorption model. The singleness of the desorption transients together with their narrow peak widths makes the technique ideally suited for a heat of vaporization spectrometer for either substance analysis or identification

  13. Enthalpy of Vaporization and Vapor Pressures: An Inexpensive Apparatus

    Science.gov (United States)

    Battino, Rubin; Dolson, David A.; Hall, Michael A.; Letcher, Trevor M.

    2007-01-01

    A simple and inexpensive method to determine the enthalpy of vaporization of liquids by measuring vapor pressure as a function of temperature is described. The vapor pressures measured with the stopcock cell were higher than the literature values and those measured with the sidearm rubber septum cell were both higher and lower than literature…

  14. Process for separating radioactive gases

    International Nuclear Information System (INIS)

    Kimura, Shigeru; Awada, Yoshihisa.

    1976-01-01

    Object: To efficiently and safely separate and recover raw gases such as krypton which requires radioactive attenuation by a long term storage. Structure: A mixture of krypton and xenon is separated by liquefaction from raw gases at a first distillation column, using latent heat of liquid nitrogen. The krypton and xenon mixture separated by liquefaction at the first distillation column is separated into krypton and xenon, by controlling operation pressure of a second distillation column at about 3 - 5 atm., using sensible heat of low temperature nitrogen gas discharged from a top of the first distillation column and a condenser. (Aizawa, K.)

  15. The ideal gases of tachyons

    International Nuclear Information System (INIS)

    Mrowczynski, St.

    1984-01-01

    The formalism of statistical mechanics of particles slower than light has been considered from the point of view of the application of this formalism for the description of tachyons. Properties of ideal gases of tachyons have been discussed in detail. After finding general formulae for quantum, Bose and Fermi gases the classical limit has been considered. It has been shown that Bose-Einstein condensation occurs. The tachyon gas of bosons violates the third principle of thermodynamics. Degenerated Fermi gas has been considered and in this case the entropy vanishes at zero temperature. Difficulties of formulating covariant statistical mechanics have been discussed

  16. A microscope for Fermi gases

    International Nuclear Information System (INIS)

    Omran, Ahmed

    2016-01-01

    This thesis reports on a novel quantum gas microscope to investigate many-body systems of fermionic atoms in optical lattices. Single-site resolved imaging of ultracold lattice gases has enabled powerful studies of bosonic quantum many-body systems. The extension of this capability to Fermi gases offers new prospects to studying complex phenomena of strongly correlated systems, for which numerical simulations are often out of reach. Using standard techniques of laser cooling, optical trapping, and evaporative cooling, ultracold Fermi gases of 6 Li are prepared and loaded into a large-scale 2D optical lattice of flexible geometry. The atomic distribution is frozen using a second, short-scaled lattice, where we perform Raman sideband cooling to induce fluorescence on each atom while maintaining its position. Together with high-resolution imaging, the fluorescence signals allow for reconstructing the initial atom distribution with single-site sensitivity and high fidelity. Magnetically driven evaporative cooling in the plane allows for producing degenerate Fermi gases with almost unity filling in the initial lattice, allowing for the first microscopic studies of ultracold gases with clear signatures of Fermi statistics. By preparing an ensemble of spin-polarised Fermi gases, we detect a flattening of the density profile towards the centre of the cloud, which is a characteristic of a band-insulating state. In one set of experiments, we demonstrate that losses of atom pairs on a single lattice site due to light-assisted collisions are circumvented. The oversampling of the second lattice allows for deterministic separation of the atom pairs into different sites. Compressing a high-density sample in a trap before loading into the lattice leads to many double occupancies of atoms populating different bands, which we can image with no evidence for pairwise losses. We therefore gain direct access to the true number statistics on each lattice site. Using this feature, we can

  17. Uranium vapor generator: pulsed hollow cathode lamp

    International Nuclear Information System (INIS)

    Carleer, M.; Gagne, J.; Leblanc, B.; Demers, Y.; Mongeau, B.

    1979-01-01

    The production of uranium vapors has been studied in the 5 L 0 6 ground state using a pulsed hollow cathode lamp. The evolution of the 238 U ( 5 L 0 6 ) concentration with time has been studied with Xe and Ar as buffer gases. A density of 2.7 x 10 13 atoms cm -3 was obtained with Xe as a buffer gas. In addition, those measurements, obtained from the absorption of a laser beam tuned to the 5758.143 A ( 5 L 0 6 -17,361 7 L 6 ) transition, allowed the determination of the transition probability A=2.1 x 10 5 sec -1 and of the branching ratio BR=0.08 for this transition

  18. Hazardous industrial gases identified using a novel polymer/MWNT composite resistance sensor array

    International Nuclear Information System (INIS)

    Yuana, C.L.; Chang, C.P.; Song, Y.

    2011-01-01

    Highlights: → In this work, a silicon wafer microelectrode substrate for a resistance sensor was fabricated using the semiconductor manufacturing process. → This work developed polymer-functionalized MWNT sensor plat forms for the detection of vapors from chemical agents at different temperatures. → Applied PCA to determine the performance of as-fabricated films for exposure to three chemical agents. - Abstract: Hazardous industrial chemical gases pose a significant threat to the environment and human life. Therefore, there is an urgent need to develop a reliable sensor for identifying these hazardous gases. In this work, a silicon wafer microelectrode substrate for a resistance sensor was fabricated using the semiconductor manufacturing process. Conductive carbon nanotubes were then mixed with six different polymers with different chemical adsorption properties to produce a composite thin film for the fabrication of a chemical sensor array. This array was then utilized to identify three hazardous gases at different temperatures. Experimental results for six polymers for chemical gases, such as tetrahydrofuran (THF), chloroform (CHCl 3 ) and methanol (MeOH) at different temperatures, indicate that the variation in sensitivity resistance increased when the sensing temperature increased. The poly(ethylene adipate)/MWNT sensing film had high sensitivity, excellent selectivity, and good reproducibility in detecting all chemical agent vapors. Additionally, this study utilized a bar chart and statistical methods in principal component analysis to identify gases with the polymer/MWNT sensor.

  19. Stratospheric aerosols and precursor gases

    Science.gov (United States)

    1982-01-01

    Measurements were made of the aerosol size, height and geographical distribution, their composition and optical properties, and their temporal variation with season and following large volcanic eruptions. Sulfur-bearing gases were measured in situ in the stratosphere, and studied of the chemical and physical processes which control gas-to-particle conversion were carried out in the laboratory.

  20. Permeability of cork to gases.

    Science.gov (United States)

    Faria, David P; Fonseca, Ana L; Pereira, Helen; Teodoro, Orlando M N D

    2011-04-27

    The permeability of gases through uncompressed cork was investigated. More than 100 samples were assessed from different plank qualities to provide a picture of the permeability distribution. A novel technique based on a mass spectrometer leak detector was used to directly measure the helium flow through the central area of small disks 10 mm in diameter and 2 mm thick. The permeability for nitrogen, oxygen, and other gases was measured by the pressure rise technique. Boiled and nonboiled cork samples from different sections were evaluated. An asymmetric frequency distribution ranging 3 orders of magnitude (roughly from 1 to 1000 μmol/(cm·atm·day)) for selected samples without macroscopic defects was found, having a peak below 100 μmol/(cm·atm·day). Correlation was found between density and permeability: higher density samples tend to show lower permeability. However, boiled cork showed a mean lower permeability despite having a lower density. The transport mechanism of gases through cork was also examined. Calculations suggest that gases permeate uncompressed cork mainly through small channels between cells under a molecular flow regime. The diameter of such channels was estimated to be in the range of 100 nm, in agreement with the plasmodesmata size in the cork cell walls.

  1. Vapor pressure and enthalpy of vaporization of linear aliphatic alkanediamines

    International Nuclear Information System (INIS)

    Pozdeev, Vasiliy A.; Verevkin, Sergey P.

    2011-01-01

    Highlights: → We measured vapor pressure of diamines H 2 N-(CH 2 ) n -NH 2 with n = 3 to 12. → Vaporization enthalpies at 298 K were derived. → We examined consistency of new and available in the literature data. → Enthalpies of vaporization show linear dependence on numbers n. → Enthalpies of vaporization correlate linearly with Kovat's indices. - Abstract: Vapor pressures and the molar enthalpies of vaporization of the linear aliphatic alkanediamines H 2 N-(CH 2 ) n -NH 2 with n = (3 to 12) have been determined using the transpiration method. A linear correlation of enthalpies of vaporization (at T = 298.15 K) of the alkanediamines with the number n and with the Kovat's indices has been found, proving the internal consistency of the measured data.

  2. Permeation, diffusion and dissolution of hydrogen isotopes, methane and inert gases through/in a tetrafluoroethylene film

    International Nuclear Information System (INIS)

    Matsuyama, M.; Miyake, H.; Ashida, K.; Watanabe, K.

    1982-01-01

    Tetrafluoroethylene (TFE) is widely used for conventional tritium handling systems such as vacuum seals, tubing and so on. We measured the permeation of the three hydrogen isotopes, methane and the inert gases through a TFE film at room temperature by means of the time-lag method in order to establish the physicochemical properties which determine the solubility and diffusivity of those gases. It was found that the diffusion constant of the inert gases changed exponentially with the heat of vaporization and the solubility was an exponential function of the Lennard-Jones force constant of the gases. On the other hand, hydrogen isotopes and methane deviated from these relations. It is concluded that chemical interactions between the solute and the solvent play an important role for the dissolution and the diffusion of these gases in TFE. (orig.)

  3. Influence of radiation absorption by environmental water vapor on radiation transfer in wildland fires

    Science.gov (United States)

    David Frankman; Brent W. Webb; Bret W. Butler

    2007-01-01

    Thermal radiation emission from a simulated black flame surface to a fuel bed is analyzed by a ray-tracing technique, tracking emission from points along the flame to locations along the fuel bed while accounting for absorption by environmental water vapor in the intervening medium. The Spectral Line Weighted-sum-of-gray-gases approach was adopted for treating the...

  4. Progress toward resolution of vapor problems associated with tank 241-C-103

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Babad, H.; Story, M.S.

    1994-02-01

    Noxious and flammable gases and vapors associated with high-level radioactive waste storage tank 241-C-103 at the Hanford Site are discussed. Focus is on the Westinghouse Hanford Company strategy to characterize the tank headspace. The sampling and analysis methodology is described. Sampling limitations, devices, and equipment are discussed. Results to date are given

  5. Monitoring tropospheric water vapor changes using radiosonde data

    International Nuclear Information System (INIS)

    Elliott, W.P.; Smith, M.E.; Angell, J.K.

    1990-01-01

    Significant increases in the water vapor content of the troposphere are expected to accompany temperature increases due to rising concentrations of the greenhouse gases. Thus it is important to follow changes in water vapor over time. There are a number of difficulties in developing a homogeneous data set, however, because of changes in radiosonde instrumentation and reporting practices. The authors report here on preliminary attempts to establish indices of water vapor which can be monitored. The precipitable water between the surface and 500 mb is the first candidate. They describe their method for calculating this quantity from radiosonde data for a network very similar to the network Angell uses for detecting temperature trends. Preliminary results suggest that the noise level is low enough to detect trends in water vapor at the individual stations. While a slight increase in global water vapor is hinted at in the data, and the data suggest there may have been a net transfer of water from the Southern Hemisphere to the Northern Hemisphere, these conclusions are tentative. The authors also discuss the future course of this investigation

  6. PREVENTION AND CONTROL OF DIMETHYLAMINE VAPORS EMISSION: HERBICIDE PRODUCTION PLANT

    Directory of Open Access Journals (Sweden)

    Zorana Arsenijević

    2008-11-01

    Full Text Available The widely used herbicide, dimethylamine salt of 2,4-dichlorophenoxy acetic acid (2,4-D-DMA, is usually prepared by mixing a dimethylamine (DMA aqueous solution with a solid 2,4-dichlorophenoxy acetic acid (2,4-D. The vapors of the both, reactants and products, are potentially hazardous for the environment. The contribution of DMA vapors in overall pollution from this process is most significant, concerning vapor pressures data of these pollutants. Therefore, the control of the air pollution in the manufacture and handling of methylamines is very important. Within this paper, the optimal air pollution control system in preparation of 2,4-D-DMA was developed for the pesticides manufacturing industry. This study employed the simple pollution prevention concept to reduce the emission of DMA vapors at the source. The investigations were performed on the pilot plant scale. To reduce the emission of DMA vapors, the effluent gases from the herbicide preparation zone were passed through the packed bed scrubber (water - scrubbing medium, and the catalytic reactor in sequence. The end result is a substantially improved air quality in the working area, as well as in the urbanized areas located near the chemical plant.

  7. Airborne DOAS retrievals of methane, carbon dioxide, and water vapor concentrations at high spatial resolution: application to AVIRIS-NG

    Directory of Open Access Journals (Sweden)

    A. K. Thorpe

    2017-10-01

    Full Text Available At local scales, emissions of methane and carbon dioxide are highly uncertain. Localized sources of both trace gases can create strong local gradients in its columnar abundance, which can be discerned using absorption spectroscopy at high spatial resolution. In a previous study, more than 250 methane plumes were observed in the San Juan Basin near Four Corners during April 2015 using the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG and a linearized matched filter. For the first time, we apply the iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS method to AVIRIS-NG data and generate gas concentration maps for methane, carbon dioxide, and water vapor plumes. This demonstrates a comprehensive greenhouse gas monitoring capability that targets methane and carbon dioxide, the two dominant anthropogenic climate-forcing agents. Water vapor results indicate the ability of these retrievals to distinguish between methane and water vapor despite spectral interference in the shortwave infrared. We focus on selected cases from anthropogenic and natural sources, including emissions from mine ventilation shafts, a gas processing plant, tank, pipeline leak, and natural seep. In addition, carbon dioxide emissions were mapped from the flue-gas stacks of two coal-fired power plants and a water vapor plume was observed from the combined sources of cooling towers and cooling ponds. Observed plumes were consistent with known and suspected emission sources verified by the true color AVIRIS-NG scenes and higher-resolution Google Earth imagery. Real-time detection and geolocation of methane plumes by AVIRIS-NG provided unambiguous identification of individual emission source locations and communication to a ground team for rapid follow-up. This permitted verification of a number of methane emission sources using a thermal camera, including a tank and buried natural gas pipeline.

  8. Airborne DOAS retrievals of methane, carbon dioxide, and water vapor concentrations at high spatial resolution: application to AVIRIS-NG

    Science.gov (United States)

    Thorpe, Andrew K.; Frankenberg, Christian; Thompson, David R.; Duren, Riley M.; Aubrey, Andrew D.; Bue, Brian D.; Green, Robert O.; Gerilowski, Konstantin; Krings, Thomas; Borchardt, Jakob; Kort, Eric A.; Sweeney, Colm; Conley, Stephen; Roberts, Dar A.; Dennison, Philip E.

    2017-10-01

    At local scales, emissions of methane and carbon dioxide are highly uncertain. Localized sources of both trace gases can create strong local gradients in its columnar abundance, which can be discerned using absorption spectroscopy at high spatial resolution. In a previous study, more than 250 methane plumes were observed in the San Juan Basin near Four Corners during April 2015 using the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) and a linearized matched filter. For the first time, we apply the iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS) method to AVIRIS-NG data and generate gas concentration maps for methane, carbon dioxide, and water vapor plumes. This demonstrates a comprehensive greenhouse gas monitoring capability that targets methane and carbon dioxide, the two dominant anthropogenic climate-forcing agents. Water vapor results indicate the ability of these retrievals to distinguish between methane and water vapor despite spectral interference in the shortwave infrared. We focus on selected cases from anthropogenic and natural sources, including emissions from mine ventilation shafts, a gas processing plant, tank, pipeline leak, and natural seep. In addition, carbon dioxide emissions were mapped from the flue-gas stacks of two coal-fired power plants and a water vapor plume was observed from the combined sources of cooling towers and cooling ponds. Observed plumes were consistent with known and suspected emission sources verified by the true color AVIRIS-NG scenes and higher-resolution Google Earth imagery. Real-time detection and geolocation of methane plumes by AVIRIS-NG provided unambiguous identification of individual emission source locations and communication to a ground team for rapid follow-up. This permitted verification of a number of methane emission sources using a thermal camera, including a tank and buried natural gas pipeline.

  9. Constrained Vapor Bubble Experiment

    Science.gov (United States)

    Gokhale, Shripad; Plawsky, Joel; Wayner, Peter C., Jr.; Zheng, Ling; Wang, Ying-Xi

    2002-11-01

    Microgravity experiments on the Constrained Vapor Bubble Heat Exchanger, CVB, are being developed for the International Space Station. In particular, we present results of a precursory experimental and theoretical study of the vertical Constrained Vapor Bubble in the Earth's environment. A novel non-isothermal experimental setup was designed and built to study the transport processes in an ethanol/quartz vertical CVB system. Temperature profiles were measured using an in situ PC (personal computer)-based LabView data acquisition system via thermocouples. Film thickness profiles were measured using interferometry. A theoretical model was developed to predict the curvature profile of the stable film in the evaporator. The concept of the total amount of evaporation, which can be obtained directly by integrating the experimental temperature profile, was introduced. Experimentally measured curvature profiles are in good agreement with modeling results. For microgravity conditions, an analytical expression, which reveals an inherent relation between temperature and curvature profiles, was derived.

  10. Investigations on the influence of NO/sub 2/ and SO/sub 2/ as well as a combination of the two gases on the production of precipitating antibodies in guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Antweiler, K; Kompch, K H; Brockhaus, A

    1975-01-01

    The influence of nitrogen dioxide and sulfur dioxide, or a combination of the two, on the production pf precipitating antibodies was studied in guinea pigs. The gas concentration was 10 mg/cu m. Continuous exposure began 3 days before sensitization and lasted up to the testing date. Sensitization was done subcutaneously and intramuscularly with fresh chicken albumen plus complete Freund's adjuvant. Production of precipitating antibodies was tested by the double diffusion method of Ouchterlony. Total protein content was measured and an immunoelectrophoretic separation of the protein fractions was performed with polyvalent anti-guinea pig serum. The statistical evaluation of the results yielded no support for an interaction of NO/sub 2/ and SO/sub 2/, or their combination, in the concentration used on the formation of precipitating bodies.

  11. PHASE BEHAVIOR OF LIGHT GASES IN HYDROCARBON AND AQUEOUS SOLVENTS

    Energy Technology Data Exchange (ETDEWEB)

    KHALED A.M. GASEM; ROBERT L. ROBINSON, JR.

    1998-08-31

    Under previous support from the Department of Energy, an experimental facility has been established and operated to measure valuable vapor-liquid equilibrium data for systems of interest in the production and processing of coal fluids. To facilitate the development and testing of models for prediction of the phase behavior for such systems, we have acquired substantial amounts of data on the equilibrium phase compositions for binary mixtures of heavy hydrocarbon solvents with a variety of supercritical solutes, including hydrogen, methane, ethane, carbon monoxide, and carbon dioxide. The present project focuses on measuring the phase behavior of light gases and water in Fischer-Tropsch (F-T) type solvents at conditions encountered in indirect liquefaction processes and evaluating and developing theoretically-based correlating frameworks to predict the phase behavior of such systems. Specific goals of the proposed work include (a) developing a state-of-the-art experimental facility to permit highly accurate measurements of equilibrium phase compositions (solubilities) of challenging F-T systems, (b) measuring these properties for systematically-selected binary, ternary and molten F-T wax mixtures to provide critically needed input data for correlation development, (c) developing and testing models suitable for describing the phase behavior of such mixtures, and (d) presenting the modeling results in generalized, practical formats suitable for use in process engineering calculations. During the present period, the Park-Gasem-Robinson (PGR) equation of state (EOS) has been modified to improve its volumetric and equilibrium predictions. Specifically, the attractive term of the PGR equation was modified to enhance the flexibility of the model, and a new expression was developed for the temperature dependence of the attractive term in this segment-segment interaction model. The predictive capability of the modified PGR EOS for vapor pressure, and saturated liquid and

  12. Vapor condensation device

    International Nuclear Information System (INIS)

    Sakurai, Manabu; Hirayama, Fumio; Kurosawa, Setsumi; Yoshikawa, Jun; Hosaka, Seiichi.

    1992-01-01

    The present invention enables to separate and remove 14 C as CO 3 - ions without condensation in a vapor condensation can of a nuclear facility. That is, the vapor condensation device of the nuclear facility comprises (1) a spray pipe for spraying an acidic aqueous solution to the evaporation surface of an evaporation section, (2) a spray pump for sending the acidic aqueous solution to the spray pipe, (3) a tank for storing the acidic aqueous solution, (4) a pH sensor for detecting pH of the evaporation section, (5) a pH control section for controlling the spray pump, depending on the result of the detection of the pH sensor. With such a constitution, the pH of liquid wastes on the vaporization surface is controlled to 7 by spraying an aqueous solution of dilute sulfuric acid to the evaporation surface, thereby enabling to increase the transfer rate of 14 C to condensates to 60 to 70%. If 14 C is separated and removed as a CO 2 gas from the evaporation surface, the pH of the liquid wastes returns to the alkaline range of 9 to 10 and the liquid wastes are returned to a heating section. The amount of spraying the aqueous solution of dilute sulfuric acid can be controlled till the pH is reduced to 5. (I.S.)

  13. The vapor pressures of explosives

    Energy Technology Data Exchange (ETDEWEB)

    Ewing, Robert G.; Waltman, Melanie J.; Atkinson, David A.; Grate, Jay W.; Hotchkiss, Peter

    2013-01-05

    The vapor pressures of many explosive compounds are extremely low and thus determining accurate values proves difficult. Many researchers, using a variety of methods, have measured and reported the vapor pressures of explosives compounds at single temperatures, or as a function of temperature using vapor pressure equations. There are large variations in reported vapor pressures for many of these compounds, and some errors exist within individual papers. This article provides a review of explosive vapor pressures and describes the methods used to determine them. We have compiled primary vapor pressure relationships traceable to the original citations and include the temperature ranges for which they have been determined. Corrected values are reported as needed and described in the text. In addition, after critically examining the available data, we calculate and tabulate vapor pressures at 25 °C.

  14. 75 FR 14081 - Mandatory Reporting of Greenhouse Gases: Minor Harmonizing Changes to the General Provisions

    Science.gov (United States)

    2010-03-24

    ... (subpart NN): (A) All fractionators. (B) All local natural gas distribution companies. Industrial greenhouse gas suppliers (subpart OO): (A) All producers of industrial greenhouse gases. (B) Importers of industrial greenhouse gases with annual bulk imports of N2O, fluorinated GHG, and CO2 that in combination are...

  15. VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

    Energy Technology Data Exchange (ETDEWEB)

    Eric M. Suuberg; Vahur Oja

    1997-07-01

    This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

  16. Greenhouse effect of trace gases, 1970-1980

    Science.gov (United States)

    Lacis, A.; Hansen, J.; Lee, P.; Lebedeff, S.; Mitchell, T.

    1981-01-01

    Increased abundances were measured for several trace atmospheric gases in the decade 1970-1980. The equilibrium greenhouse warming for the measured increments of CH4, chlorofluorocarbons and N2O is between 50% and 100% of the equilibrium warming for the measured increase of atmospheric CO2 during the same 10 years. The combined warming of CO2 and trace gases should exceed natural global temperature variability in the 1980's and cause the global mean temperature to rise above the maximum of the late 1930's.

  17. Soliton Gases and Generalized Hydrodynamics

    Science.gov (United States)

    Doyon, Benjamin; Yoshimura, Takato; Caux, Jean-Sébastien

    2018-01-01

    We show that the equations of generalized hydrodynamics (GHD), a hydrodynamic theory for integrable quantum systems at the Euler scale, emerge in full generality in a family of classical gases, which generalize the gas of hard rods. In this family, the particles, upon colliding, jump forward or backward by a distance that depends on their velocities, reminiscent of classical soliton scattering. This provides a "molecular dynamics" for GHD: a numerical solver which is efficient, flexible, and which applies to the presence of external force fields. GHD also describes the hydrodynamics of classical soliton gases. We identify the GHD of any quantum model with that of the gas of its solitonlike wave packets, thus providing a remarkable quantum-classical equivalence. The theory is directly applicable, for instance, to integrable quantum chains and to the Lieb-Liniger model realized in cold-atom experiments.

  18. Noble Gases in Lakes and Ground Waters

    OpenAIRE

    Kipfer, Rolf; Aeschbach-Hertig, Werner; Peeters, Frank; Stute, Marvin

    2002-01-01

    In contrast to most other fields of noble gas geochemistry that mostly regard atmospheric noble gases as 'contamination,' air-derived noble gases make up the far largest and hence most important contribution to the noble gas abundance in meteoric waters, such as lakes and ground waters. Atmospheric noble gases enter the meteoric water cycle by gas partitioning during air / water exchange with the atmosphere. In lakes and oceans noble gases are exchanged with the free atmosphere at the surface...

  19. Centrifugal separation of mixture gases

    International Nuclear Information System (INIS)

    Zhou, M.S.; Chen, W.N.; Yin, Y.T.

    2008-01-01

    An attempt for single centrifugal separation of mixtures with different molecular formula was presented in this paper. The mixtures of SF 6 and CCl 3 F, and SF 6 and CCl 4 were chosen as the processing gases, which were prepared in three mass ratios, 0.5, 0.8 and 0.2, respectively. The separating characteristics such as the overall separation factors and the variation of cuts were studied. (author)

  20. The method of determination of mercury adsorption from flue gases

    Directory of Open Access Journals (Sweden)

    Budzyń Stanisław

    2017-01-01

    Full Text Available For several recent years Faculty of Energy and Fuels of the AGH University of Science and Technology in Krakow conduct intensive studies on the occurrence of mercury contained in thermal and coking coals, as well as on the possible reduction of fossil-fuel mercury emissions. This research focuses, among others, on application of sorbents for removal of mercury from flue gases. In this paper we present the methodology for testing mercury adsorption using various types of sorbents, in laboratory conditions. Our model assumes burning a coal sample, with a specific mercury content, in a strictly determined time period and temperature conditions, oxygen or air flow rates, and the flow of flue gases through sorbent in a specific temperature. It was developed for particular projects concerning the possibilities of applying different sorbents to remove mercury from flue gases. Test stand itself is composed of a vertical pipe furnace inside which a quartz tube was mounted for sample burning purposes. At the furnace outlet, there is a heated glass vessel with a sorbent sample through which flue gases are passing. Furnace allows burning at a defined temperature. The exhaust gas flow path is heated to prevent condensation of the mercury vapor prior to contact with a sorbent. The sorbent container is positioned in the heating element, with controlled and stabilized temperature, which allows for testing mercury sorption in various temperatures. Determination of mercury content is determined before (coal and sorbent, as well as after the process (sorbent and ash. The mercury balance is calculated based on the Hg content determination results. This testing method allows to study sorbent efficiency, depending on sorption temperature, sorbent grain size, and flue-gas rates.

  1. Landfill gases and some effects on vegetation

    Science.gov (United States)

    Franklin B. Flower; Ida A. Leone; Edward F. Gilman; John J. Arthur

    1977-01-01

    Gases moving from refuse landfills through soil were studied in New Jersey. The gases, products of anaerobic decomposition of organic matter in the refuse, caused injury and death of peach trees, ornamentals, and commercial farm crops, and create possible hazards to life and property because of the entrance of combustible gases into residences. Remedial measures are...

  2. Reactions on carbonaceous materials with hydrogenating gases

    Energy Technology Data Exchange (ETDEWEB)

    Pier, M; Simon, W; Kronig, W

    1933-02-08

    A process is given for the production of valuable hydrocarbons by treatment of distillable carbonaceous materials with added hydrogenating gases under pressure in contact with catalysts. The process comprises adding to the initial materials before or during the said treatment organic sulphonic acids together with metals of groups 4 to 8 of the periodic system or compounds thereof, or free organic carboxylic acids which when inorganic salts are simultaneously present do not combine therewith to form complex ansolvo acids, or acid salts of strong acids or acid salts of heavy metals, lithium, magnesium, and aluminum, with the exception of aluminum hydrosilicates, or inorganic oxygen containing acids of sulfur or nitrogen or the anhydrides of said inorganic oxygen-containing acids.

  3. Vapor pressures and vapor compositions in equilibrium with hypostoichiometric plutonium dioxide at high temperatures

    International Nuclear Information System (INIS)

    Green, D.W.; Fink, J.K.; Leibowitz, L.

    1982-01-01

    Vapor pressures and vapor compositions have been calculated for 1500 less than or equal to T less than or equal to 4000 0 K. Thermodynamic functions for the condensed phase and for each of the gaseous species were combined with an oxygen-potential model extended into the liquid region to obtain the partial pressures of O 2 , O, Pu, PuO and PuO 2 . The calculated oxygen pressures increase very rapidly as stoichiometry is approached. At least part of this increase is a consequence of the exclusion of Pu 6 + from the oxygen-potential model. No reliable method was found to estimate the importance of this ion. As a result of large oxygen potentials at high temperatures, extremely high total pressures that produced unreasonably high vapor densities were calculated. The highest temperature was therefore limited to 400 K, and the range of oxygen-to-metal ratios was limited to 1.994 to 1.70. These calculations show that vapor in equilibrium with hypostoichiometric plutonium dioxide is poorly approximated as PuO 2 for most of the temperture and composition range of interest. The vapor is much more oxygen-rich than the condensed phase. Implications for the (U,Pu)O/sub 2-x/ system are discussed

  4. Adsorption of Dissolved Gases (CH4, CO2, H2, Noble Gases) by Water-Saturated Smectite Clay Minerals

    Science.gov (United States)

    Bourg, I. C.; Gadikota, G.; Dazas, B.

    2016-12-01

    Adsorption of dissolved gases by water-saturated clay minerals plays important roles in a range of fields. For example, gas adsorption in on clay minerals may significantly impact the formation of CH4 hydrates in fine-grained sediments, the behavior of CH4 in shale, CO2 leakage across caprocks of geologic CO2 sequestration sites, H2 leakage across engineered clay barriers of high-level radioactive waste repositories, and noble gas geochemistry reconstructions of hydrocarbon migration in the subsurface. Despite its importance, the adsorption of gases on clay minerals remains poorly understood. For example, some studies have suggested that clay surfaces promote the formation of CH4 hydrates, whereas others indicate that clay surfaces inhibit the formation of CH4 hydrates. Here, we present molecular dynamics (MD) simulations of the adsorption of a range of gases (CH4, CO2, H2, noble gases) on clay mineral surfaces. Our results indicate that the affinity of dissolved gases for clay mineral surfaces has a non-monotone dependence on the hydrated radius of the gas molecules. This non-monotone dependence arises from a combination of two effects: the polar nature of certain gas molecules (in particular, CO2) and the templating of interfacial water structure by the clay basal surface, which results in the presence of interfacial water "cages" of optimal size for intermediate-size gas molecules (such as Ne or Ar).

  5. Method for the generation of variable density metal vapors which bypasses the liquidus phase

    Science.gov (United States)

    Kunnmann, Walter; Larese, John Z.

    2001-01-01

    The present invention provides a method for producing a metal vapor that includes the steps of combining a metal and graphite in a vessel to form a mixture; heating the mixture to a first temperature in an argon gas atmosphere to form a metal carbide; maintaining the first temperature for a period of time; heating the metal carbide to a second temperature to form a metal vapor; withdrawing the metal vapor and the argon gas from the vessel; and separating the metal vapor from the argon gas. Metal vapors made using this method can be used to produce uniform powders of the metal oxide that have narrow size distribution and high purity.

  6. A study on vapor explosions

    International Nuclear Information System (INIS)

    Takagi, N.; Shoji, M.

    1979-01-01

    An experimental study was carried out for vapor explosions of molten tin falling in water. For various initial metal temperatures and subcooling of water, transient pressure of the explosions, relative frequency of the explosions and the position where the explosions occur were measured in detail. The influence of ambient pressure was also investigated. From the results, it was concluded that the vapor explosion is closely related to the collapse of a vapor film around the molten metal. (author)

  7. Distribution of gases in the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois

    Science.gov (United States)

    Striegl, Robert G.

    1988-01-01

    The unsaturated zone is a medium that provides pneumatic communication for the movement of gases from wastes buried in landfills to the atmosphere, biota, and groundwater. Gases in unsaturated glacial and eolian deposits near a waste-disposal trench at the low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois, were identified, and the spatial and temporal distributions of the partial pressures of those gases were determined for the period January 1984 through January 1986. Methods for the collection and analyses of the gases are described, as are geologic and hydrologic characteristics of the unsaturated zone that affect gas transport. The identified gases, which are of natural and of waste origin, include nitrogen, oxygen, and argon, carbon dioxide, methane, propane, butane, tritiated water vapor, 14carbon dioxide, and 222 radon. Concentrations of methane and 14carbon dioxide originated at the waste, as shown by partial-pressure gradients of the gases; 14carbon dioxide partial pressures exceeded natural background partial pressures by factors greater than 1 million at some locations. Variations in partial pressures of oxygen and carbon dioxide were seasonal among piezometers because of increased root and soil-microbe respiration during summer. Variations in methane and 14carbon dioxide partial pressures were apparently related to discrete releases from waste sources at unpredictable intervals of time. No greater than background partial pressures for tritiated water vapor or 222 radon were measured. (USGS)

  8. Nuclear system vaporization

    International Nuclear Information System (INIS)

    Bougault, R.; Brou, R.; Colin, J.; Cussol, D.; Durand, D.; Le Brun, C.; Lecolley, J.F.; Lopez, O.; Louvel, M.; Nakagawa, T.; Peter, J.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Yuasa-Nakagawa, K.; Wieloch, A.

    1998-01-01

    A particular case of the hot nuclei de-excitation is the total nuclear dislocation into light particles (n, p, d, t, 3 He and α). Such events were first observed at bombarding energies lower than 100 MeV/nucleon due to high detection performances of the INDRA multidetector. The light system Ar + Ni was studied at several bombarding energies ranging from 32 to 95 MeV/nucleon. The events associated to a total vaporization of the system occur above the energy threshold of ∼ 50 MeV/nucleon. A study of the form of these events shows that we have essentially two sources. The excitation energy of these sources may be determined by means of the kinematic properties of their de-excitation products. A preliminary study results in excitation energy values of the order 10 - 14 MeV/nucleon. The theoretical calculation based on a statistical model modified to take into account high excitation energies and excited levels in the lightest nuclei predicts that the vaporization of the two partner nuclei in the Ar + Ni system takes place when the excitation energy exceeds 12 MeV/nucleon what is qualitatively in agreement with the values deduced from calorimetric analysis

  9. Textbook Forum. Thermodynamics of "Mixing" of Ideal Gases: A Persistent Pitfall.

    Science.gov (United States)

    Meyer, Edwin F.

    1987-01-01

    Discusses some of the misconceptions commonly held suggesting that mixing ideal gases causes an increase in entropy. Argues that the combining processes and resulting total pressure have absolutely nothing to do with the mixing itself. (TW)

  10. Vaporization of fault water during seismic slip

    Science.gov (United States)

    Chen, Jianye; Niemeijer, André R.; Fokker, Peter A.

    2017-06-01

    Laboratory and numerical studies, as well as field observations, indicate that phase transitions of pore water might be an important process in large earthquakes. We present a model of the thermo-hydro-chemo-mechanical processes, including a two-phase mixture model to incorporate the phase transitions of pore water, occurring during fast slip (i.e., a natural earthquake) in order to investigate the effects of vaporization on the coseismic slip. Using parameters from typical natural faults, our modeling shows that vaporization can indeed occur at the shallow depths of an earthquake, irrespective of the wide variability of the parameters involved (sliding velocity, friction coefficient, gouge permeability and porosity, and shear-induced dilatancy). Due to the fast kinetics, water vaporization can cause a rapid slip weakening even when the hydrological conditions of the fault zone are not favorable for thermal pressurization, e.g., when permeability is high. At the same time, the latent heat associated with the phase transition causes the temperature rise in the slip zone to be buffered. Our parametric analyses reveal that the amount of frictional work is the principal factor controlling the onset and activity of vaporization and that it can easily be achieved in earthquakes. Our study shows that coseismic pore fluid vaporization might have played important roles at shallow depths of large earthquakes by enhancing slip weakening and buffering the temperature rise. The combined effects may provide an alternative explanation for the fact that low-temperature anomalies were measured in the slip zones at shallow depths of large earthquakes.

  11. The fabrication of vertically aligned and periodically distributed carbon nanotube bundles and periodically porous carbon nanotube films through a combination of laser interference ablation and metal-catalyzed chemical vapor deposition.

    Science.gov (United States)

    Yuan, Dajun; Lin, Wei; Guo, Rui; Wong, C P; Das, Suman

    2012-06-01

    Scalable fabrication of carbon nanotube (CNT) bundles is essential to future advances in several applications. Here, we report on the development of a simple, two-step method for fabricating vertically aligned and periodically distributed CNT bundles and periodically porous CNT films at the sub-micron scale. The method involves laser interference ablation (LIA) of an iron film followed by CNT growth via iron-catalyzed chemical vapor deposition. CNT bundles with square widths ranging from 0.5 to 1.5 µm in width, and 50-200 µm in length, are grown atop the patterned catalyst over areas spanning 8 cm(2). The CNT bundles exhibit a high degree of control over square width, orientation, uniformity, and periodicity. This simple scalable method of producing well-placed and oriented CNT bundles demonstrates a high application potential for wafer-scale integration of CNT structures into various device applications, including IC interconnects, field emitters, sensors, batteries, and optoelectronics, etc.

  12. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford waste tank 241-S-101: Results from samples collected on 06/06/96

    International Nuclear Information System (INIS)

    Thomas, B.L.; Evans, J.C.; Pool, K.H.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-S-101. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained. Analyte concentrations were based on analytical results and sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed

  13. Deflagration explosion of an unconfined fuel vapor cloud

    International Nuclear Information System (INIS)

    Taki, S.; Ogawa, Y.

    1981-01-01

    In the reported study, explosions are produced by injecting a small amount of liquefied petroleum gas (LPG) into air. The ignition and subsequent evolution of the explosion of the unconfined vapor cloud are observed by the simultaneous use of direct photographs and pressure recording. The intensity of the compression waves generated by unconfined combustion are modeled on the basis of the solution of the conservation equations for the flow associated with a spherically symmetric expanding piston. The obtained results are compared with the measurements. It is pointed out that the development of unconfined fuel vapor cloud explosions can be divided into two stages, including a deflagration propagating in premixed gases, which is followed by a diffusion flame promoted by buoyancy and convection. The experimental result from the pressure measurement is found to be quantitatively consistent with the result obtained from the spherical piston model

  14. Greenhouse Gases and Animal Agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, J. (ed.) [Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido (Japan); Young, B.A. (ed.) [The University of Queensland, Gatton, Queensland 4343 (Australia)

    2002-07-01

    Reports from interdisciplinary areas including microbiology, biochemistry, animal nutrition, agricultural engineering and economics are integrated in this proceedings. The major theme of this book is environmental preservation by controlling release of undesirable greenhouse gases to realize the sustainable development of animal agriculture. Technology exists for the effective collection of methane generated from anaerobic fermentation of animal effluent and its use as a biomass energy source. Fossil fuel consumption can be reduced and there can be increased use of locally available energy sources. In addition, promoting environmentally-conscious agriculture which does not rely on the chemical fertilizer can be realized by effective use of animal manure and compost products.

  15. Mechanics of liquids and gases

    CERN Document Server

    Loitsyanskii, L G; Jones, W P

    1966-01-01

    Mechanics of Liquids and Gases, Second Edition is a 10-chapter text that covers significant revisions concerning the dynamics of an ideal gas, a viscous liquid and a viscous gas.After an expanded introduction to the fundamental properties and methods of the mechanics of fluids, this edition goes on dealing with the kinetics and general questions of dynamics. The next chapters describe the one-dimensional pipe flow of a gas with friction, the elementary theory of the shock tube; Riemann's theory of the wave propagation of finite intensity, and the theory of plane subsonic and supersonic flows.

  16. Dew point of gases with low sulfuric acid content

    Energy Technology Data Exchange (ETDEWEB)

    Fieg, J.

    1981-07-01

    Discusses control of air pollution caused by sulfur compounds in solid fuels during combustion. Excessive amount of oxygen during combustion leads to formation of sulfur trioxide. Sulfur trioxide reacts with water vapor and forms sulfuric acid. Chemical reactions which lead to formation of sulfuric acid are described. Conditions for sulfuric acid condensation are analyzed. Several methods for determining dew point of flue gases with low sulfuric acid content are reviewed: methods based on determination of electric conductivity of condensed sulfuric acid (Francis, Cheney, Kiyoure), method based on determination of sulfuric acid concentration in the gaseous phase and in the liquid phase after cooling (Lee, Lisle and Sensenbaugh, Ross and Goksoyr). (26 refs.) (In Polish)

  17. Modeling vapor liquid equilibrium of ionic liquids + gas binary systems at high pressure with cubic equations of state

    Directory of Open Access Journals (Sweden)

    A. C. D. Freitas

    2013-03-01

    Full Text Available Ionic liquids (IL have been described as novel environmentally benign solvents because of their remarkable characteristics. Numerous applications of these solvents continue to grow at an exponential rate. In this work, high pressure vapor liquid equilibria for 17 different IL + gas binary systems were modeled at different temperatures with Peng-Robinson (PR and Soave-Redlich-Kwong (SRK equations of state, combined with the van der Waals mixing rule with two binary interaction parameters (vdW-2. The experimental data were taken from the literature. The optimum binary interaction parameters were estimated by minimization of an objective function based on the average absolute relative deviation of liquid and vapor phases, using the modified Simplex algorithm. The solubilities of all gases studied in this work decrease as the temperature increases and increase with increasing pressure. The correlated results were highly satisfactory, with average absolute relative deviations of 2.10% and 2.25% for PR-vdW-2 and SRK-vdW-2, respectively.

  18. Unmanned Aerial Systems for Monitoring Trace Tropospheric Gases

    Directory of Open Access Journals (Sweden)

    Travis J. Schuyler

    2017-10-01

    Full Text Available The emission of greenhouse gases (GHGs has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes <100 m above ground level that can achieve spatiotemporal resolution on the order of meters and seconds. Unmanned aerial systems (UASs can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces the most relevant classes of UASs available and evaluates their suitability to operate three kinds of detectors for atmospheric trace gases. The three subsets of UASs discussed are: (1 micro aerial vehicles (MAVs; (2 vertical take-off and landing (VTOL; and, (3 low-altitude short endurance (LASE systems. The trace gas detectors evaluated are first the vertical cavity surface emitting laser (VCSEL, which is an infrared laser-absorption technique; second two types of metal-oxide semiconductor sensors; and, third a modified catalytic type sensor. UASs with wingspans under 3 m that can carry up to 5 kg a few hundred meters high for at least 30 min provide the best cost and convenience compromise for sensors deployment. Future efforts should be focused on the calibration and validation of lightweight analytical systems mounted on UASs for quantifying trace atmospheric gases. In conclusion, UASs offer new and exciting opportunities to study atmospheric composition and its effect on weather patterns and climate change.

  19. Thermodynamics of the vaporization of uranium tetrabromide

    International Nuclear Information System (INIS)

    Singh, Z.; Prasad, R.; Venugopal, P.V.; Roy, K.N.; Sood, D.D.

    1981-01-01

    Vapour pressures of solid and liquid uranium tetrabromide have been measured in the temperature range of 696 to 805 K and 805 to 1003 K respectively by transpiration and evaporation-temperature techniques. The vapour pressures obtained by the two techniques are in good agreement and have been combined to give the reported vapour-pressure equations for solid and liquid uranium tetrabromide. The melting temperature, the normal boiling temperature, the standard enthalpy of vaporization ΔH 0 (vap, 298.15 K), and the standard entropy of vaporization ΔS 0 (vap, 298.15 K) are reported. The enthalpy of fusion ΔH 0 (fus, 802 K) is also reported. The thermodynamic quantities from the present study are compared with those in the literature and critically analysed. (author)

  20. Chemical vapor composites (CVC)

    International Nuclear Information System (INIS)

    Reagan, P.

    1993-01-01

    The Chemical Vapor Composite, CVC trademark , process fabricates composite material by simply mixing particles (powders and or fibers) with CVD reactants which are transported and co-deposited on a hot substrate. A key feature of the CVC process is the control provided by varing the density, geometry (aspect ratio) and composition of the entrained particles in the matrix material, during deposition. The process can fabricate composite components to net shape (± 0.013 mm) on a machined substrate in a single step. The microstructure of the deposit is described and several examples of different types of particles in the matrix are illustrated. Mechanical properties of SiC composite material fabricated with SiC powder and fiber will be presented. Several examples of low cost ceramic composite products will be shown. (orig.)

  1. Iron bromide vapor laser

    Science.gov (United States)

    Sukhanov, V. B.; Shiyanov, D. V.; Trigub, M. V.; Dimaki, V. A.; Evtushenko, G. S.

    2016-03-01

    We have studied the characteristics of a pulsed gas-discharge laser on iron bromide vapor generating radiation with a wavelength of 452.9 nm at a pulse repetition frequency (PRF) of 5-30 kHz. The maximum output power amounted to 10 mW at a PRF within 5-15 kHz for a voltage of 20-25 kV applied to electrodes of the discharge tube. Addition of HBr to the medium produced leveling of the radial profile of emission. Initial weak lasing at a wavelength of 868.9 nm was observed for the first time, which ceased with buildup of the main 452.9-nm line.

  2. Vapor-droplet flow equations

    International Nuclear Information System (INIS)

    Crowe, C.T.

    1975-01-01

    General features of a vapor-droplet flow are discussed and the equations expressing the conservation of mass, momentum, and energy for the vapor, liquid, and mixture using the control volume approach are derived. The phenomenological laws describing the exchange of mass, momentum, and energy between phases are also reviewed. The results have application to development of water-dominated geothermal resources

  3. Toward high value sensing: monolayer-protected metal nanoparticles in multivariable gas and vapor sensors.

    Science.gov (United States)

    Potyrailo, Radislav A

    2017-08-29

    For detection of gases and vapors in complex backgrounds, "classic" analytical instruments are an unavoidable alternative to existing sensors. Recently a new generation of sensors, known as multivariable sensors, emerged with a fundamentally different perspective for sensing to eliminate limitations of existing sensors. In multivariable sensors, a sensing material is designed to have diverse responses to different gases and vapors and is coupled to a multivariable transducer that provides independent outputs to recognize these diverse responses. Data analytics tools provide rejection of interferences and multi-analyte quantitation. This review critically analyses advances of multivariable sensors based on ligand-functionalized metal nanoparticles also known as monolayer-protected nanoparticles (MPNs). These MPN sensing materials distinctively stand out from other sensing materials for multivariable sensors due to their diversity of gas- and vapor-response mechanisms as provided by organic and biological ligands, applicability of these sensing materials for broad classes of gas-phase compounds such as condensable vapors and non-condensable gases, and for several principles of signal transduction in multivariable sensors that result in non-resonant and resonant electrical sensors as well as material- and structure-based photonic sensors. Such features should allow MPN multivariable sensors to be an attractive high value addition to existing analytical instrumentation.

  4. Phase structure of strongly correlated Fermi gases

    International Nuclear Information System (INIS)

    Roscher, Dietrich

    2015-01-01

    Strongly correlated fermionic many-body systems are ubiquitous in nature. Their theoretical description poses challenging problems which are further complicated when imbalances in, e.g., the particle numbers of the involved species or their masses are introduced. In this thesis, a number of different approaches is developed and applied in order to obtain predictions for physical observables of such systems that mutually support and confirm each other. In a first step, analytically well-founded mean-field analyses are carried through. One- and three-dimensional ultracold Fermi gases with spin and mass imbalance as well as Gross-Neveu and NJL-type relativistic models at finite baryon chemical potential are investigated with respect to their analytic properties in general and the occurrence of spontaneous breaking of translational invariance in particular. Based on these studies, further methods are devised or adapted allowing for investigations also beyond the mean-field approximation. Lattice Monte Carlo simulations with imaginary imbalance parameters are employed to surmount the infamous sign problem and compute the equation of state of the respective unitary Fermi gases. Moreover, in-medium two-body analyses are used to confirm and explain the characteristics of inhomogeneously ordered phases. Finally, functional RG methods are applied to the unitary Fermi gas with spin and mass imbalance. Besides quantitatively competitive predictions for critical temperatures for the superfluid state, strong hints on the stability of inhomogeneous phases with respect to order parameter fluctuations in the regime of large mass imbalance are obtained. Combining the findings from these different theoretical studies suggests the possibility to find such phases in experiments presently in preparation.

  5. Vapor pressure and enthalpy of vaporization of aliphatic propanediamines

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Chernyak, Yury

    2012-01-01

    Highlights: ► We measured vapor pressure of four aliphatic 1,3-diamines. ► Vaporization enthalpies at 298 K were derived. ► We examined consistency of new and available data in the literature. ► A group-contribution method for prediction was developed. - Abstract: Vapor pressures of four aliphatic propanediamines including N-methyl-1,3-propanediamine (MPDA), N,N-dimethyl-1,3-propanediamine (DMPDA), N,N-diethyl-1,3-propanediamine (DEPDA) and N,N,N′,N′-tetramethyl-1,3-propanediamine (4MPDA) were measured using the transpiration method. The vapor pressures developed in this work and reported in the literature were used to derive molar enthalpy of vaporization values at the reference temperature 298.15 K. An internal consistency check of the enthalpy of vaporization was performed for the aliphatic propanediamines studied in this work. A group-contribution method was developed for the validation and prediction vaporization enthalpies of amines and diamines.

  6. Using in situ bioventing to minimize soil vapor extraction costs

    International Nuclear Information System (INIS)

    Downey, D.C.; Frishmuth, R.A.; Archabal, S.R.; Pluhar, C.J.; Blystone, P.G.; Miller, R.N.

    1995-01-01

    Gasoline-contaminated soils may be difficult to remediate with bioventing because high concentrations of gasoline vapors become mobile when air is injected into the soil. Because outward vapor migration is often unacceptable on small commercial sites, soil vapor extraction (SVE) or innovative bioventing techniques are required to control vapors and to increase soil gas oxygen levels to stimulate hydrocarbon biodegradation. Combinations of SVE, off-gas treatment, and bioventing have been used to reduce the costs normally associated with remediation of gasoline-contaminated sites. At Site 1, low rates of pulsed air injection were used to provide oxygen while minimizing vapor migration. At Site 2, a period of high-rate SVE and off-gas treatment was followed by long-term air injection. Site 3 used an innovative approach that combined regenerative resin for ex situ vapor treatment with in situ bioventing to reduce the overall cost of site remediation. At each of these Air Force sites, bioventing provided cost savings when compared to more traditional SVE methods

  7. Water-pirotube boiler: influence of its design in fabrication cost. Calderas de vapor pirotubulares: influencia del diseo en el coste de fabricacion

    Energy Technology Data Exchange (ETDEWEB)

    Latre Durso, F.

    1993-01-01

    Design of water-tube boiler and its cost is analyzed. Adequated combination of gases velocity, size of tubes, gases temperature, geometric configuration, etc will give a best product with quality prize relation. (Author)

  8. A Citizen's Guide to Vapor Intrusion Mitigation

    Science.gov (United States)

    This guide describes how vapor intrusion is the movement of chemical vapors from contaminated soil and groundwater into nearby buildings.Vapors primarily enter through openings in the building foundation or basement walls.

  9. Vapor pressure measured with inflatable plastic bag

    Science.gov (United States)

    1965-01-01

    Deflated plastic bag in a vacuum chamber measures initial low vapor pressures of materials. The bag captures the test sample vapors and visual observation of the vapor-inflated bag under increasing external pressures yields pertinent data.

  10. Solvent vapor annealing of an insoluble molecular semiconductor

    KAUST Repository

    Amassian, Aram

    2010-01-01

    Solvent vapor annealing has been proposed as a low-cost, highly versatile, and room-temperature alternative to thermal annealing of organic semiconductors and devices. In this article, we investigate the solvent vapor annealing process of a model insoluble molecular semiconductor thin film - pentacene on SiO 2 exposed to acetone vapor - using a combination of optical reflectance and two-dimensional grazing incidence X-ray diffraction measurements performed in situ, during processing. These measurements provide valuable and new insight into the solvent vapor annealing process; they demonstrate that solvent molecules interact mainly with the surface of the film to induce a solid-solid transition without noticeable swelling, dissolving or melting of the molecular material. © 2010 The Royal Society of Chemistry.

  11. Comparison of vapor sampling system (VSS) and in situ vapor sampling (ISVS) methods on Tanks C-107, BY-108, and S-102

    International Nuclear Information System (INIS)

    Huckaby, J.L.; Edwards, J.A.; Evans, J.C.

    1996-05-01

    The objective of this report is to evaluate the equivalency of two methods used to sample nonradioactive gases and vapors in the Hanford Site high-level waste tank headspaces. In addition to the comparison of the two sampling methods, the effects of an in-line fine particle filter on sampling results are also examined to determine whether results are adversely affected by its presence. This report discusses data from a January 1996 sampling

  12. A novel approach to scavenging anesthetic gases in rodent surgery.

    Science.gov (United States)

    Nesbitt, Jeffrey C; Krageschmidt, Dale A; Blanco, Michael C

    2013-01-01

    Laboratory animal procedures using gas anesthetics may amass elevated waste gas concentrations in operating rooms if controls are not implemented for capturing and removing the vapors. Area sampling using an infrared analyzer indicated isoflurane concentrations likely to exceed occupational exposure guidelines. Our study showed environmental concentrations of oxygen as high as 40% and isoflurane concentrations >100 ppm when no controls or merely passive controls were utilized. These extraneous isoflurane emissions were determined to be originating from the pre-procedural induction process as well as the gas delivery nose cone. A novel waste gas collection cylinder was designed to enclose the gas delivery nose cone and animal head during the administration of anesthetic gases. The vented cylinder utilized a house vacuum to remove the waste anesthetic gases from the surgical field. A commercially available induction chamber designed to be actively and externally exhausted was used to lower concentrations during the induction process. With implementation of local exhaust ventilation controls, waste anesthetic gas concentrations decreased to below recommended occupational exposure levels. In vitro (sham) testing compared favorably to in vivo measurements validating the reduction capability of active ventilation during rodent anesthetic administration. In vivo isoflurane reductions for the induction chamber emissions, the operating room, and the surgeon's breathing zone were 95%, 60%, and 53%, respectively. The same measurements for an in vitro procedure were 98%, 84%, and 87%, respectively.

  13. Experimental studies concerning the drying of voloxidizer off-gases

    International Nuclear Information System (INIS)

    Holland, W.D.; Shah, A.H.; Kaiser, A.F.; McGee, J.C.

    1981-07-01

    The results of an experimental program conducted to aid in the design of a tritium retention system to remove tritiated water from voloxidizer off-gases are presented. The retention system is expected to be a fixed-bed adsorption unit using a commercially available desiccant, such as molecular sieves, to dry the off-gases. The presence of iodine in the off-gas stream somewhat complicates the drying process since some iodine will be retained in the drying bed along with the tritiated water. The present work represents a follow-up to a study in which a small-scale (2-in.-diam by 30-in.-long) packed column of Linde Molecular Sieves (LMS) type 3A was repeatedly loaded and regenerated using a non-radioactive simulated voloxidizer off-gas containing water and iodine vapor. Both water and iodine loadings were measured and the regeneration characteristics of the bed were observed. The following studies were carried out: (1) testing of other desiccants showed LMS type 3A to be superior because of its high water loading and low iodine retention; (2) development of a column-mounted moisture detector; (3) adsorption isotherms; (4) iodine analysis using a commercial oxidant monitor; (5) tests on cartridge-type beds - a series of tests were conducted using three small drying beds connected in series. One further finding of this study was the importance of the clay binder (used in pelletized molecular sieves) in obtaining satisfactory or acceptably low iodine retention

  14. Throat gases against the CO2

    International Nuclear Information System (INIS)

    Michaut, C.

    2006-01-01

    The steel production needs carbon consumption and generates carbon dioxide, the main greenhouse gases. It represents about 6 % of the greenhouse gases emissions in the world. That is why the steel industry began last year a research program, Ideogaz, to reduce its CO 2 releases. The first results on the throat gases recovery seems very promising: it uses 25 % less of carbon. The author presents the program and the main technical aspects of the method. (A.L.B.)

  15. Optical Lattice Gases of Interacting Fermions

    Science.gov (United States)

    2015-12-02

    interacting Fermi gases has topological properties similar to the conventional chiral p- wave state. These include a non-zero Chern number and the...interacting cold gases with broad impacts on the interfaces with condensed matter and particle physics . Applications and experiments of some of the physics ...AFRL-AFOSR-VA-TR-2016-0016 Optical Lattice Gases of Interacting Fermions Wensheng Vincent Liu UNIVERSITY OF PITTSBURGH Final Report 12/02/2015

  16. Phase-equilibria for design of coal-gasification processes: dew points of hot gases containing condensible tars. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Prausnitz, J.M.

    1980-05-01

    This research is concerned with the fundamental physical chemistry and thermodynamics of condensation of tars (dew points) from the vapor phase at advanced temperatures and pressures. Fundamental quantitative understanding of dew points is important for rational design of heat exchangers to recover sensible heat from hot, tar-containing gases that are produced in coal gasification. This report includes essentially six contributions toward establishing the desired understanding: (1) Characterization of Coal Tars for Dew-Point Calculations; (2) Fugacity Coefficients for Dew-Point Calculations in Coal-Gasification Process Design; (3) Vapor Pressures of High-Molecular-Weight Hydrocarbons; (4) Estimation of Vapor Pressures of High-Boiling Fractions in Liquefied Fossil Fuels Containing Heteroatoms Nitrogen or Sulfur; and (5) Vapor Pressures of Heavy Liquid Hydrocarbons by a Group-Contribution Method.

  17. A 3-D radiation model for non-grey gases

    International Nuclear Information System (INIS)

    Selcuk, Nevin; Doner, Nimeti

    2009-01-01

    A three-dimensional radiation code based on method of lines (MOL) solution of discrete ordinates method (DOM) coupled with spectral line-based weighted sum of grey gases (SLW) model for radiative heat transfer in non-grey absorbing-emitting media for use in conjunction with a computational fluid dynamics (CFD) code based on the same approach was developed. The code was applied to three test problems: two containing isothermal homogenous/non-homogenous water vapor and one non-isothermal water vapor/carbon dioxide mixture. Predictive accuracy of the code was evaluated by benchmarking its steady-state predictions against accurate results, calculated by ray tracing method with statistical narrow band model, available in the literature. Comparative testing with solutions of other methods is also provided. Comparisons reveal that MOL solution of DOM with SLW model provides accurate solutions for radiative heat fluxes and source terms and can be used with confidence in conjunction with CFD codes based on MOL

  18. Origin and Evolution of Reactive and Noble Gases Dissolved in Matrix Pore Water

    Energy Technology Data Exchange (ETDEWEB)

    Eichinger, F. [Hydroisotop GmbH, Schweitenkirchen (Germany); Rock-Water Interaction, Institute of Geological Sciences, University of Bern, Bern (Switzerland); Waber, H. N. [Rock-Water Interaction, Institute of Geological Sciences, University of Bern, Bern (Switzerland); Smellie, J. A.T. [Conterra AB, Stockholm (Sweden)

    2013-07-15

    Reactive and noble gases dissolved in matrix pore water of low permeable crystalline bedrock were successfully extracted and characterized for the first time based on drillcore samples from the Olkiluoto investigation site (SW Finland). Interaction between matrix pore water and fracture groundwater occurs predominately by diffusion. Changes in the chemical and isotopic composition of gases dissolved in fracture groundwater are transmitted and preserved in the pore water. Absolute concentrations, their ratios and the stable carbon isotope signature of hydrocarbon gases dissolved in pore water give valuable indications about the evolution of these gases in the nearby flowing fracture groundwaters. Inert noble gases dissolved in matrix pore water and their isotopes combined with their in situ production and accumulation rates deliver information about the residence time of pore water. (author)

  19. Unconventional gases: a North-American energy revolution not without consequences for Europe

    International Nuclear Information System (INIS)

    2011-01-01

    This paper gives a definition of the different existing unconventional gases (coal-bed methane, tight gases, shale gases), and outlines that, although these gases as well as the techniques to extract them have been well known for a long time, it is the combination of two of these techniques (hydraulic fracturing or fracking, and horizontal drilling) which enables the current technological development and the exploitation of these gases. It also outlines that the current situation in terms of natural resources favours such a development. It evokes projects in the United States, China, India, Europe, and more particularly in France, stressing that environmental issues and population density in Europe are obstacles to perform these drillings. The author questions the production cost issue and explains how these developments, notably in the USA, may change completely the world energetic landscape, and therefore entail a review of the European energy agenda. He explores the possible consequences of a durable decrease of gas prices

  20. Erosion of volatile elemental condensed gases by keV electron and light-ion bombardment

    International Nuclear Information System (INIS)

    Schou, J.

    1991-11-01

    Erosion of the most volatile elemental gases by keV electron and light-ion bombardment has been studied at the experimental setup at Risoe. The present work includes frozen neon, argon, krypton, nitrogen, oxygen and three hydrogen isotopes, deuterium, hydrogen deuteride and hydrogen. The yield of these condensed gases has been measured as a function of film thickness and primary energy for almost all combinations of primary particles (1-3 keV electrons, 5-10 keV hydrogen- and helium ions) and ices. These and other existing results show that there are substantial common features for the sputtering of frozen elemental gases. Within the two groups, the solid rare gases and the solid molecular gases, the similarity is striking. The hydrogenic solids deviate in some respects from the other elements. The processes that liberate kinetic energy for the particle ejection in sputtering are characteristic of the specific gas. (au) 3 tabs., 12 ills., 159 refs

  1. Noble gases in nuclear medicine

    International Nuclear Information System (INIS)

    Calderon, M.; Burdine, J.A.

    1973-01-01

    Radioactive noble gases have made a significant contribution to diagnostic nuclear medicine. In the area of regional assessment of pulmonary function, 133 Xe has had its greatest clinical impact. Following a breath of 133 Xe gas, pulmonary ventilation can be measured using a scintillation camera or other appropriate radiation detector. If 133 Xe dissolved in saline is injected intravenously, both pulmonary capillary perfusion and ventilation can be measured since 90 percent of the highly insoluble xenon escapes into the alveoli during the first passage through the lungs. Radionuclide pulmonary function tests provide the first qualitative means of assessing lung ventilation and blood flow on a regional basis, and have recently been extended to include quantification of various parameters of lung function by means of a small computer interfaced to the scintillation camera. 133 Xe is also used in the measurement of organ blood flow following injection into a vessel leading into an organ such as the brain, heart kidneys, or muscles

  2. The vaporization enthalpies and vapor pressures of fatty acid methyl esters C18, C21 to C23, and C25 to C29 by correlation - gas chromatography

    International Nuclear Information System (INIS)

    Chickos, James S.; Zhao Hui; Nichols, Gary

    2004-01-01

    Vapor pressures and vaporization enthalpies for methyl heptadecanoate and methyl heneicosanoate to methyl octacosanoate exclusive of methyl tricosanoate are evaluated as a function of temperature over the temperature range T = 298.15-450 K by correlation gas chromatography. The results are generated by an extrapolative process using literature values for methyl tetradecanoate to methyl eicosanoate as standards. Relationships for calculating vapor pressures of the title compounds from T = 298.15 to 450 K are provided. Experimental fusion enthalpies are also reported for the methyl esters from methyl hexadecanoate to methyl octacosanoate excluding methyl tridecanoate. Vaporization enthalpies and fusion enthalpies adjusted for temperature to T = 298.15 K are combined to provide sublimation enthalpies. The results are compared to available literature values. A rationale for the linear relationship observed between enthalpies of vaporization and enthalpies of transfer from solution to the vapor is also provided

  3. Energy efficiency and greenhouse gases

    International Nuclear Information System (INIS)

    Hamburg, A.; Martins, A.; Pesur, A.; Roos, I.

    1996-01-01

    Estonia's energy balance for 1990 - 1994 is characterized by the dramatic changes in the economy after regaining independence in 1991. In 1990 - 1993, primary energy supply decreased about 1.9 times. The reasons were a sharp decrease in exports of electric energy and industrial products, a steep increase in fuel prices and the transition from the planned to a market-oriented economy. Over the same period, the total amount of emitted greenhouse gases decreased about 45%. In 1993, the decrease in energy production and consumption stopped, and in 1994, a moderate increase occurred (about 6%), which is a proof stabilizing economy. Oil shale power engineering will remain the prevailing energy resource for the next 20 - 25 years. After stabilization, the use of oil shale will rise in Estonia's economy. Oil shale combustion in power plants will be the greatest source of greenhouse gases emissions in near future. The main problem is to decrease the share of CO 2 emissions from the decomposition of carbonate part of oil shale. This can be done by separating limestone particles from oil shale before its burning by use of circulating fluidized bed combustion technology. Higher efficiency of oil shale power plants facilitates the reduction of CO 2 emissions per generated MWh electricity considerably. The prognoses for the future development of power engineering depend essentially on the environmental requirements. Under the highly restricted development scenario, which includes strict limitations to emissions (CO 2 , SO 2 , thermal waste) and a severe penalty system, the competitiveness of nuclear power will increase. The conceptual steps taken by the Estonian energy management should be in compliance with those of neighboring countries, including the development programs of the other Baltic states

  4. Passive vapor extraction feasibility study

    International Nuclear Information System (INIS)

    Rohay, V.J.

    1994-01-01

    Demonstration of a passive vapor extraction remediation system is planned for sites in the 200 West Area used in the past for the disposal of waste liquids containing carbon tetrachloride. The passive vapor extraction units will consist of a 4-in.-diameter pipe, a check valve, a canister filled with granular activated carbon, and a wind turbine. The check valve will prevent inflow of air that otherwise would dilute the soil gas and make its subsequent extraction less efficient. The granular activated carbon is used to adsorb the carbon tetrachloride from the air. The wind turbine enhances extraction rates on windy days. Passive vapor extraction units will be designed and operated to meet all applicable or relevant and appropriate requirements. Based on a cost analysis, passive vapor extraction was found to be a cost-effective method for remediation of soils containing lower concentrations of volatile contaminants. Passive vapor extraction used on wells that average 10-stdft 3 /min air flow rates was found to be more cost effective than active vapor extraction for concentrations below 500 parts per million by volume (ppm) of carbon tetrachloride. For wells that average 5-stdft 3 /min air flow rates, passive vapor extraction is more cost effective below 100 ppm

  5. The lithium vapor box divertor

    International Nuclear Information System (INIS)

    Goldston, R J; Schwartz, J; Myers, R

    2016-01-01

    It has long been recognized that volumetric dissipation of the plasma heat flux from a fusion power system is preferable to its localized impingement on a material surface. Volumetric dissipation mitigates both the anticipated very high heat flux and intense particle-induced damage due to sputtering. Recent projections to a tokamak demonstration power plant suggest an immense upstream parallel heat flux, of order 20 GW m −2 , implying that fully detached operation may be a requirement for the success of fusion power. Building on pioneering work on the use of lithium by Nagayama et al and by Ono et al as well as earlier work on the gas box divertor by Watkins and Rebut, we present here a concept for a lithium vapor box divertor, in which lithium vapor extracts momentum and energy from a fusion-power-plant divertor plasma, using fully volumetric processes. At the high powers and pressures that are projected this requires a high density of lithium vapor, which must be isolated from the main plasma in order to avoid lithium build-up on the chamber walls or in the plasma. Isolation is achieved through a powerful multi-box differential pumping scheme available only for condensable vapors. The preliminary box-wise calculations are encouraging, but much more work is required to demonstrate the practical viability of this scheme, taking into account at least 2D plasma and vapor flows within and between the vapor boxes and out of the vapor boxes to the main plasma. (paper)

  6. Probing the interaction of noble gases with pristine and nitrogen-doped graphene through Raman spectroscopy

    Science.gov (United States)

    Cunha, Renato; Perea-López, Néstor; Elías, Ana Laura; Fujisawa, Kazunori; Carozo, Victor; Feng, Simin; Lv, Ruitao; dos Santos, Maria Cristina; Terrones, Mauricio; Araujo, Paulo T.

    2018-05-01

    The interactions of adsorbates with graphene have received increasing attention due to its importance in the development of applications involving graphene-based coatings. Here, we present a study of the adsorption of noble gases on pristine and nitrogen-doped graphene. Single-layer graphene samples were synthesized by chemical vapor deposition (CVD) and transferred to transmission electron microscopy (TEM) grids. Several noble gases were allowed to adsorb on the suspended graphene substrate at very low temperatures. Raman spectra show distinct frequency blue shifts in both the 2D and G bands, which are induced by gas adsorption onto high quality single layer graphene (1LG). These shifts, which we associate with compressive biaxial strain in the graphene layers induced by the noble gases, are negligible for nitrogen-doped graphene. Additionally, a thermal depinning transition, which is related to the desorption of a noble gas layer from the graphene surface at low temperatures (ranging from 20 to 35 K), was also observed at different transition temperatures for different noble gases. These transition temperatures were found to be 25 K for argon and 35 K for xenon. Moreover, we were able to obtain values for the compressive biaxial strain in graphene induced by the adsorbed layer of noble gases, using Raman spectroscopy. Ab initio calculations confirmed the correlation between the noble gas-induced strain and the changes in the Raman features observed.

  7. Health assessment of gasoline and fuel oxygenate vapors: Neurotoxicity evaluation

    OpenAIRE

    O?Callaghan, James P.; Daughtrey, Wayne C.; Clark, Charles R.; Schreiner, Ceinwen A.; White, Russell

    2014-01-01

    Sprague?Dawley rats were exposed via inhalation to vapor condensates of either gasoline or gasoline combined with various fuel oxygenates to assess potential neurotoxicity of evaporative emissions. Test articles included vapor condensates prepared from ?baseline gasoline? (BGVC), or gasoline combined with methyl tertiary butyl ether (G/MTBE), ethyl t-butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), ethanol (G/EtOH), or t-butyl alcohol (G/TBA). Target concentrati...

  8. Polybenzimidazole-based mixed membranes with exceptional high water vapor permeability and selectivity

    KAUST Repository

    Akhtar, Faheem Hassan

    2017-09-13

    Polybenzimidazole (PBI), a thermal and chemically stable polymer, is commonly used to fabricate membranes for applications like hydrogen recovery at temperatures of more than 300 °C, fuel cells working in a highly acidic environment, and nanofiltration in aggressive solvents. This report shows for the first time use of PBI dense membranes for water vapor/gas separation applications. They showed an excellent selectivity and high water vapor permeability. Incorporation of inorganic hydrophilic titanium-based nano-fillers into the PBI matrix further increased the water vapor permeability and water vapor/N2 selectivity. The most selective mixed matrix membrane with 0.5 wt% loading of TiO2 nanotubes yielded a water vapor permeability of 6.8×104 Barrer and a H2O/N2 selectivity of 3.9×106. The most permeable membrane with 1 wt% loading of carboxylated TiO2 nanoparticles had a 7.1×104 Barrer water vapor permeability and a H2O/N2 selectivity of 3.1×106. The performance of these membranes in terms of water vapor transport and selectivity is among the highest reported ones. The remarkable ability of PBI to efficiently permeate water versus other gases opens the possibility to fabricate membranes for dehumidification of streams in harsh environments. This includes the removal of water from high temperature reaction mixtures to shift the equilibrium towards products.

  9. Polybenzimidazole-based mixed membranes with exceptional high water vapor permeability and selectivity

    KAUST Repository

    Akhtar, Faheem Hassan; Kumar, Mahendra; Villalobos, Luis Francisco; Shevate, Rahul; Vovusha, Hakkim; Schwingenschlö gl, Udo; Peinemann, Klaus-Viktor

    2017-01-01

    Polybenzimidazole (PBI), a thermal and chemically stable polymer, is commonly used to fabricate membranes for applications like hydrogen recovery at temperatures of more than 300 °C, fuel cells working in a highly acidic environment, and nanofiltration in aggressive solvents. This report shows for the first time use of PBI dense membranes for water vapor/gas separation applications. They showed an excellent selectivity and high water vapor permeability. Incorporation of inorganic hydrophilic titanium-based nano-fillers into the PBI matrix further increased the water vapor permeability and water vapor/N2 selectivity. The most selective mixed matrix membrane with 0.5 wt% loading of TiO2 nanotubes yielded a water vapor permeability of 6.8×104 Barrer and a H2O/N2 selectivity of 3.9×106. The most permeable membrane with 1 wt% loading of carboxylated TiO2 nanoparticles had a 7.1×104 Barrer water vapor permeability and a H2O/N2 selectivity of 3.1×106. The performance of these membranes in terms of water vapor transport and selectivity is among the highest reported ones. The remarkable ability of PBI to efficiently permeate water versus other gases opens the possibility to fabricate membranes for dehumidification of streams in harsh environments. This includes the removal of water from high temperature reaction mixtures to shift the equilibrium towards products.

  10. Dimers in nucleating vapors

    Science.gov (United States)

    Lushnikov, A. A.; Kulmala, M.

    1998-09-01

    The dimer stage of nucleation may affect considerably the rate of the nucleation process at high supersaturation of the nucleating vapor. Assuming that the dimer formation limits the nucleation rate, the kinetics of the particle formation-growth process is studied starting with the definition of dimers as bound states of two associating molecules. The partition function of dimer states is calculated by summing the Boltzmann factor over all classical bound states, and the equilibrium population of dimers is found for two types of intermolecular forces: the Lennard-Jones (LJ) and rectangular well+hard core (RW) potentials. The principle of detailed balance is used for calculating the evaporation rate of dimers. The kinetics of the particle formation-growth process is then investigated under the assumption that the trimers are stable with respect to evaporation and that the condensation rate is a power function of the particle mass. If the power exponent λ=n/(n+1) (n is a non-negative integer), the kinetics of the process is described by a finite set of moments of particle mass distribution. When the characteristic time of the particle formation by nucleation is much shorter than that of the condensational growth, n+2 universal functions of a nondimensional time define the kinetic process. These functions are calculated for λ=2/3 (gas-to-particle conversion in the free molecular regime) and λ=1/2 (formation of islands on surfaces).

  11. The influence of water vapor on atmospheric exchange measurements with an ICOS* based Laser absorption analyzer

    Science.gov (United States)

    Bunk, Rüdiger; Quan, Zhi; Wandel, Matthias; Yi, Zhigang; Bozem, Heiko; Kesselmeier, Jürgen

    2014-05-01

    Carbonyl sulfide and carbon monoxide are both atmospheric trace gases of high interest. Recent advances in the field of spectroscopy have enabled instruments that measure the concentration of the above and other trace gases very fast and with good precision. Increasing the effective path length by reflecting the light between two mirrors in a cavity, these instruments reach impressive sensitivities. Often it is possible to measure the concentration of more than one trace gas at the same time. The OCS/CO2 Analyzer by LGR (Los Gatos Research, Inc.) measures the concentration of water vapor [H2O], carbonyl sulfide [COS], carbon dioxide [CO2] and carbon monoxide [CO] simultaneously. For that the cavity is saturated with light, than the attenuation of light is measured as in standard absorption spectroscopy. The instrument proved to be very fast with good precision and to be able to detect even very low concentrations, especially for COS (as low as 30ppt in the case of COS). However, we observed a rather strong cross sensitivity to water vapor. Altering the water vapor content of the sampled air with two different methods led to a change in the perceived concentration of COS, CO and CO2. This proved especially problematic for enclosure (cuvette) measurements, where the concentrations of one of the above species in an empty cuvette are compared to the concentration of another cuvette containing a plant whose exchange of trace gases with the atmosphere is of interest. There, the plants transpiration leads to a large difference in water vapor content between the cuvettes and that in turn produces artifacts in the concentration differences between the cuvettes for the other above mentioned trace gases. For CO, simultaneous measurement with a UV-Emission Analyzer (AL 5002, Aerolaser) and the COS/CO Analyzer showed good agreement of perceived concentrations as long as the sample gas was dry and an increasing difference in perceived concentration when the sample gas was

  12. Effect of sweep gas chemistry on vaporization of Li4SiO4

    International Nuclear Information System (INIS)

    Yamawaki, M.; Yamaguchi, K.

    1995-01-01

    Gas/solid equilibria in the system Li 4 SiO 4 -D 2 -D 2 O were studied by means of Knudsen effusion mass spectrometry. A Knudsen effusion mass spectrometer was modified to enable studies of reactions of hydrogen and/or water vapor with ceramic breeder materials. A gas inlet system was constructed to allow the introduction of gases into a platinum Knudsen cell, from which the equilibrated gaseous reaction products effuse. From the experimental results, it has been deduced that the equilibrium constants of vaporization reactions differ correspondingly to the nonstoichiometry of lithium orthosilicate. ((orig.))

  13. Quality and Control of Water Vapor Winds

    Science.gov (United States)

    Jedlovec, Gary J.; Atkinson, Robert J.

    1996-01-01

    Water vapor imagery from the geostationary satellites such as GOES, Meteosat, and GMS provides synoptic views of dynamical events on a continual basis. Because the imagery represents a non-linear combination of mid- and upper-tropospheric thermodynamic parameters (three-dimensional variations in temperature and humidity), video loops of these image products provide enlightening views of regional flow fields, the movement of tropical and extratropical storm systems, the transfer of moisture between hemispheres and from the tropics to the mid- latitudes, and the dominance of high pressure systems over particular regions of the Earth. Despite the obvious larger scale features, the water vapor imagery contains significant image variability down to the single 8 km GOES pixel. These features can be quantitatively identified and tracked from one time to the next using various image processing techniques. Merrill et al. (1991), Hayden and Schmidt (1992), and Laurent (1993) have documented the operational procedures and capabilities of NOAA and ESOC to produce cloud and water vapor winds. These techniques employ standard correlation and template matching approaches to wind tracking and use qualitative and quantitative procedures to eliminate bad wind vectors from the wind data set. Techniques have also been developed to improve the quality of the operational winds though robust editing procedures (Hayden and Veldon 1991). These quality and control approaches have limitations, are often subjective, and constrain wind variability to be consistent with model derived wind fields. This paper describes research focused on the refinement of objective quality and control parameters for water vapor wind vector data sets. New quality and control measures are developed and employed to provide a more robust wind data set for climate analysis, data assimilation studies, as well as operational weather forecasting. The parameters are applicable to cloud-tracked winds as well with minor

  14. Neurophysiological Assessment of Auditory, Peripheral Nerve, Somatosensory, and Visual System Function After Developmental Exposure to Gasoline, E15 and E85 Vapors

    Science.gov (United States)

    The use of gasolines blended with a range of ethanol concentrations may result in inhalation of vapors containing a variable combination of ethanol with other volatile gasoline constituents. The possibility of exposure and potential interactions between vapor constituents suggest...

  15. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Tank 241-S-107: Results from samples collected on 06/18/96

    International Nuclear Information System (INIS)

    Pool, K.H.; Evans, J.C.; Thomas, B.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-S-107 (Tank S-107) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National. Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, on sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices

  16. Assessment of the MELCOR 1.8.6 condensation heat transfer model under the presence of noncondensable gases

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Ji Min; Lee, Dong Hun; Jeong, Jae Jun [Pusan National University, Busan (Korea, Republic of)

    2016-05-15

    Condensation heat transfer under the presence of noncondensable gases (NCGs) is an important issue in nuclear safety because the presence of even a small quantity of NC gases in the vapor largely reduces the condensation rate. The extensive assessment of the condensation model of the safety analysis codes has been also performed. When NCGs are present, the condensation phenomenon is largely reduced by accumulated NCGs near the condensing surface. Since the total pressure remains constant, the partial pressure of vapor at the liquid-vapor interface is lower than that in the bulk mixture, providing the driving force for vapor diffusion towards the liquid-vapor interface. The main objective of the present study is the assessment of the condensation heat transfer model of the severe accident code MELCOR 1.8.6 under the presence of NCGs. In this study, the condensation heat transfer model of the MELCOR 1.8.6 is assessed using various experiments which have 4 different types of geometry. Through the comparison of the results, it was shown that the MELCOR code generally under-predicts the condensation heat transfer except the condensation on outer surface of vertical pipes and improvement is needed for other geometries.

  17. 40 CFR 89.312 - Analytical gases.

    Science.gov (United States)

    2010-07-01

    ... determined to calibration gas tolerances by chromatographic analysis of total hydrocarbons plus impurities or.... (2) Mixtures of gases having the following chemical compositions shall be available: (i) C3H8 and... check gases shall contain propane with 350 ppmC ±75 ppmC hydrocarbon. The three oxygen interference...

  18. Greenhouse Gases Concentrations in the Atmosphere Along ...

    African Journals Online (AJOL)

    This study investigated effect of vehicular emission on greenhouse gases concentrations along selected roads of different traffic densities in Abeokuta, Ogun State, Nigeria. Nine roads comprised highway, commercial and residential were selected. Greenhouse Gases (GHGs) were determined from both sides of the roads by ...

  19. Specific heats of degenerate ideal gases

    OpenAIRE

    Caruso, Francisco; Oguri, Vitor; Silveira, Felipe

    2017-01-01

    From arguments based on Heisenberg's uncertainty principle and Pauli's exclusion principle, the molar specific heats of degenerate ideal gases at low temperatures are estimated, giving rise to values consistent with the Nerst-Planck Principle (third law of Thermodynamics). The Bose-Einstein condensation phenomenon based on the behavior of specific heat of massive and non-relativistic boson gases is also presented.

  20. Method for storing radioactive rare gases

    International Nuclear Information System (INIS)

    Watabe, Atsushi; Nagao, Hiroyuki; Takiguchi, Yukio; Kanazawa, Toshio; Soya, Masataka.

    1975-01-01

    Object: To safely and securely store radioactive rare gases for a long period of time. Structure: The waste gases produced in nuclear power plant are cooled by a cooler and then introduced into a low temperature adsorbing device so that the gases are adsorbed by adsorbents, and then discharged into atmosphere through the purifying gas discharge line. When the radioactive rare gases reach a level of saturation in the amount of adsorption, they are heated and extracted by a suction pump and heated by a heater. The gases are then introduced into an oxygen-impurity removing device and the purified rare gases containing no oxygen and impurities are cooled by a cooler and fed into a gas holder. When the amount of radioactive rare gases stored within the gas holder reaches a given level, they are compressed and sealed by a compressure into a storing cylinder and residual gases in the piping are sucked and recovered into the gas holder, after which the cylinder is removed and stored in a fixed room. (Kamimura, M.)

  1. Tubing For Sampling Hydrazine Vapor

    Science.gov (United States)

    Travis, Josh; Taffe, Patricia S.; Rose-Pehrsson, Susan L.; Wyatt, Jeffrey R.

    1993-01-01

    Report evaluates flexible tubing used for transporting such hypergolic vapors as those of hydrazines for quantitative analysis. Describes experiments in which variety of tubing materials, chosen for their known compatibility with hydrazine, flexibility, and resistance to heat.

  2. Vapor trap for liquid metal

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T

    1968-05-22

    In a pipe system which transfers liquid metal, inert gas (cover gas) is packed above the surface of the liquid metal to prevent oxidization of the liquid. If the metal vapor is contained in such cover gas, the circulating system of the cover gas is blocked due to condensation of liquid metal inside the system. The present invention relates to an improvement in vapor trap to remove the metal vapor from the cover gas. The trap consists of a cylindrical outer body, an inlet nozzle which is deeply inserted inside the outer body and has a number of holes to inject the cove gas into the body, metal mesh or steel wool which covers the exterior of the nozzle and on which the condensation of the metal gas takes place, and a heater wire hich is wound around the nozzle to prevent condensation of the metal vapor at the inner peripheral side of the mesh.

  3. Method of contacting solids and gases

    Energy Technology Data Exchange (ETDEWEB)

    1942-08-06

    A continuous method is described for contacting solids and gases. The process involves passing a confined stream of gases through an extended path including a treating zone and imposing a pressure on the stream of gases at least sufficient to overcome the resistence of said path to the flow of said gases. A solid in finely divided form is then introduced into said stream of gases, maintaining a vertical column of finely divided solid in fluidized state of a height which will produce a pressure at the column bottom at least equal to the gas pressure at the point of entry of the solids into the stream. The solids then pass from the bottom of the column into the stream.

  4. Theoretical investigation of output features of a diode-pumped rubidium vapor laser

    Science.gov (United States)

    Wang, You; Cai, He; Zhang, Wei; Xue, Liangping; Wang, Hongyuan; Han, Juhong

    2014-02-01

    In the recent years, diode-pumped alkali lasers (DPALs) have been paid many attentions because of their excellent performances. In fact, the characteristics of a DPAL strongly depend on the physical features of buffer gases. In this report, we selected a diode-pumped rubidium vapor laser (DPRVL), which is an important type among three common DPALs, to investigate how the characteristics of a DPRVL are affected by different conditions. The results signify that the population ratio of two excitation energy-levels are close to that corresponding to thermal equilibrium as the pressure of buffer gases and the temperature of a vapor cell become higher. It has been found that quenching of the upper levels cannot be simply ignored especially for the case of weak pump. The conclusions are thought to be helpful for the configuration design of an end-pumped DPAL.

  5. Kinetic Theory of Granular Gases

    Energy Technology Data Exchange (ETDEWEB)

    Trizac, Emmanuel [Center of Theoretical Biological Physics, UC San Diego, La Jolla, CA 92093-0374 (United States); Laboratoire de Physique Theorique et Modeles Statistiques, Campus Universitaire, 91405 Orsay (France)

    2005-11-25

    Granular gases are composed of macroscopic bodies kept in motion by an external energy source such as a violent shaking. The behaviour of such systems is quantitatively different from that of ordinary molecular gases: due to the size of the constituents, external fields have a stronger effect on the dynamics and, more importantly, the kinetic energy of the gas is no longer a conserved quantity. The key role of the inelasticity of collisions has been correctly appreciated for about fifteen years, and the ensuing consequences in terms of phase behaviour or transport properties studied in an increasing and now vast body of literature. The purpose of this book is to help the newcomer to the field in acquiring the essential theoretical tools together with some numerical techniques. As emphasized by the authors-who were among the pioneers in the domain- the content could be covered in a one semester course for advanced undergraduates, or it could be incorporated in a more general course dealing with the statistical mechanics of dissipative systems. The book is self-contained, clear, and avoids mathematical complications. In order to elucidate the main physical ideas, heuristic points of views are sometimes preferred to a more rigorous route that would lead to a longer discussion. The 28 chapters are short; they offer exercises and worked examples, solved at the end of the book. Each part is supplemented with a relevant foreword and a useful summary including take-home messages. The editorial work is of good quality, with very few typographical errors. In spite of the title, kinetic theory stricto sensu is not the crux of the matter covered. The authors discuss the consequences of the molecular chaos assumption both at the individual particle level and in terms of collective behaviour. The first part of the book addresses the mechanics of grain collisions. It is emphasized that considering the coefficient of restitution {epsilon} -a central quantity governing the

  6. Kinetic Theory of Granular Gases

    International Nuclear Information System (INIS)

    Trizac, Emmanuel

    2005-01-01

    Granular gases are composed of macroscopic bodies kept in motion by an external energy source such as a violent shaking. The behaviour of such systems is quantitatively different from that of ordinary molecular gases: due to the size of the constituents, external fields have a stronger effect on the dynamics and, more importantly, the kinetic energy of the gas is no longer a conserved quantity. The key role of the inelasticity of collisions has been correctly appreciated for about fifteen years, and the ensuing consequences in terms of phase behaviour or transport properties studied in an increasing and now vast body of literature. The purpose of this book is to help the newcomer to the field in acquiring the essential theoretical tools together with some numerical techniques. As emphasized by the authors-who were among the pioneers in the domain- the content could be covered in a one semester course for advanced undergraduates, or it could be incorporated in a more general course dealing with the statistical mechanics of dissipative systems. The book is self-contained, clear, and avoids mathematical complications. In order to elucidate the main physical ideas, heuristic points of views are sometimes preferred to a more rigorous route that would lead to a longer discussion. The 28 chapters are short; they offer exercises and worked examples, solved at the end of the book. Each part is supplemented with a relevant foreword and a useful summary including take-home messages. The editorial work is of good quality, with very few typographical errors. In spite of the title, kinetic theory stricto sensu is not the crux of the matter covered. The authors discuss the consequences of the molecular chaos assumption both at the individual particle level and in terms of collective behaviour. The first part of the book addresses the mechanics of grain collisions. It is emphasized that considering the coefficient of restitution ε -a central quantity governing the inelasticity of

  7. The storage of greenhouse gases

    International Nuclear Information System (INIS)

    Herzog, H.; Kaarstad, O.; Eliasson, B

    2000-01-01

    Since 1850, that is to say the beginning of the industrial era,the concentration of carbon dioxide in the atmosphere has risen from 280 ppm to 370 ppm, this increase is mainly due to the combustion of fossil fuels. Today fossil fuels represent 85% of all the energy used in the world. Fearing progressive climatic changes, more and more governments become aware of the necessity of reducing the emission of greenhouse gases. A more efficient use of energy and the promoting of renewable energies and of the nuclear energy are the most evident solutions but they appear to be insufficient. A third solution is the storage of carbon dioxide in geological layers. This technique has been put into use since 1996 in Norway. An off-shore natural gas platform injects carbon dioxide in a geological reservoir situated 1000 meters below the ocean bed. The injection of CO 2 could be used in oil fields in order to facilitate the extraction of petroleum. Far more large and efficient reservoirs would be the oceans, they already hold up 40000 10 9 tons of dissolved CO 2 . Even if the double of the carbon dioxide accumulated in the atmosphere since 1850 were injected, the concentration of carbon in sea waters would rise by less than 2%. The safety of CO 2 storage and the impact on the environment of ocean injection sites are being studied. (A.C.)

  8. Greenhouse gases and emissions trading

    International Nuclear Information System (INIS)

    LeBlanc, A.; Dudek, D.J.

    1993-01-01

    Global cooperation is essential in cutting greenhouse-gas emissions, say Alice LeBlanc and Daniel J. Dudek of the Environmental Defense in New York City. The first step, they continue, is agreement among nations on an overall global limit for all greenhouse gases, followed by an allocation of the global limit among nations. The agreements must contain effective reporting and monitoring systems and enforcement provisions, they add. The Framework Convention on Climate Change, signed by most nations of the world in Brazil in 1992, provides the foundation for such an agreement, LeBlanc and Dudek note. open-quotes International emissions trading is a way to lower costs and expand reduction options for the benefit of all,close quotes they contend. Under such an arrangement, an international agency would assign allowances, stated in tons of carbon dioxide. Countries would be free to buy and sell allowances, but no country could exceed, in a given year, the total allowances it holds. By emitting less than its allowed amount, a country would accumulate more allowances, which it could sell. The authors claim such a system would offer benefits to the world economy by saving billions of dollars in pollution-reduction costs while still achieving emission limits established in an international agreement

  9. Development of a personal multi-pollutant exposure sampler for particulate matter and criteria gases

    Energy Technology Data Exchange (ETDEWEB)

    Chang, I.T.; Sarnat, J.; Wolfson, J.M.; Rojas-Bracho, L.; Suh, H.H.; Koutrakis, P. [Harvard Univ., Boston, MA (United States). School of Public Health

    1999-12-01

    A novel personal sampler is reported which allows simultaneous measurement of PM{sub 2,5}, and PM{sub 10}, ozone, nitrogen dioxide, and sulfur dioxide. This method combines previously used samplers for personal mass measurement with passive samplers for criteria gases and uses a single pump. Preliminarily results are reported for laboratory chamber tests and field comparisons with reference methods for both mass and criteria gases. These results demonstrate the suitability of this sampler of exposure assessment studies. (authors)

  10. Yang—Yang thermodynamics of one-dimensional Bose gases with anisotropic transversal confinement

    International Nuclear Information System (INIS)

    Hao Ya-Jiang; Yin Xiang-Guo

    2011-01-01

    By combining the thermodynamic Bethe ansatz and local density approximation, we investigate the Yang—Yang thermodynamics of interacting one-dimensional Bose gases with anisotropic transversal confinement. It is shown that with the increase of anisotropic parameter at low temperature, the Bose atoms are distributed over a wider region, while at high temperature the density distribution is not affected obviously. Both the temperature and transversal confinement can strengthen the local pressure of the Bose gases. (general)

  11. Beneficial Effects of Environmental Gases: Health Prospective

    International Nuclear Information System (INIS)

    Hussein, A.Z.; IBrahim, M.S.; Zakaria, Kh.M.

    2009-01-01

    Radioactive radon gas is widely considered to be a health hazard by environmental agencies in the United States and in Europe. Yet despite the warnings of these agencies, thousands of people annually expose themselves to radon for therapeutic purposes, in facilities ranging from rustic old mines, to upscale spas and clinics. The inert natural radioactive gas radon has been used since the beginning of the century in the treatment of rheumatic diseases. In many places in the world, radon is used for therapeutic purposes for various diseases. Radon inhalation is applied in a thermal gallery with atmospheric radon concentrations up to 100 kBq/m3, elevated temperature up to 41 EC , and humidity close to 100%, or in the form of radon baths where Rn is emanated from water with high natural Rn activity. Frequently, a combination of both treatment procedures is applied. Evidence from empirical experience and from clinical observational studies suggests that radon has analgesic, anti inflammatory and immune-stimulating effects. Ozone is one of nature's most powerful oxidants. It increases the effectiveness of the antioxidant enzyme system, which scavenge excess free radicals in the body. It is used in water purification and sewage treatment and is now being applied medically to treat many diseases from wounds and colitis to cancer, stroke and AIDS. According to the dosage and concentration range, medical ozone is a pharmaceutical agent that exerts specific properties and a well-defined range of efficacy. This paper describes the medical application of environmental gases: radon and ozone

  12. Joint Effect of Particle Charge and Adsorbable Foreign Gases on Vapor Condensation on Fine Aerosol Particles

    Czech Academy of Sciences Publication Activity Database

    Levdansky, V.V.; Smolík, Jiří; Moravec, Pavel

    2008-01-01

    Roč. 35, č. 10 (2008), s. 1246-1248 ISSN 0735-1933 R&D Projects: GA AV ČR(CZ) IAA400720804 Institutional research plan: CEZ:AV0Z40720504 Keywords : charged particle * adsorption * condensation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.332, year: 2008

  13. Study of electrophysical processes during spontaneous combustion of gases and vapors of organic substances

    Energy Technology Data Exchange (ETDEWEB)

    Fialkov, B.S.; Shebeko, Yu.N.; Muravlev, V.K.; Il' in, A.B.

    Combustion of organic substances is accompanied by non-equilibrium ionization, the greatest degree of ionization being in the high temperature zone of the flame, although notable concentrations of ions have been observed in the earlier, low temperature stages of combustion. Since this phenomenon has been studied for only a small number of compounds, a study was undertaken of the electrophysical phenomena taking place during spontaneous combustion of a large variety of compounds, viz., ethanol, acetone, benzene, diethylamine, pentane, diethyl ether, A-72 gasoline, dibromotetrafluoroethane, dichloromethane, and three mixtures of ethanol with 1,2-dibromotetrafluoroethane. Relationships of temperature to passive sonde potential and conductivity current during the induction period were determined. The effective activation energy for the conductivity current-temperature relationship was found to be 230 kilojoules per mole, which agrees with that determined for the induction period in the spontaneous combustion of acetylene-air mixtures in shock waves. 14 references, 3 figures.

  14. 29 CFR 1926.55 - Gases, vapors, fumes, dusts, and mists.

    Science.gov (United States)

    2010-07-01

    ... Limit calculated from the formula 250 (k) %SiO2+5 Cristobalite Amorphous, including natural diatomaceous...) 50 (or 15 mg/m3 whichever is the smaller) of total dust SiO2 [Inert or Nuisance Dusts includes... 94 X Ferbam 14484-64-1 Total dust — 15 — Ferrovanadium dust 12604-58-9 — 1 — Fibrous Glass Total dust...

  15. 41 CFR 50-204.50 - Gases, vapors, fumes, dusts, and mists.

    Science.gov (United States)

    2010-07-01

    ... Soapstone 20 Talc 20 Portland cement 50 Graphite (natural) 15 Coat dust (respirable fraction less than 5% Si...-selector with the following characteristics: Aerodynamic diameter (unit density sphere) Percent passing...

  16. Treating distillable carbonaceous materials with hydrocarbon gases, etc

    Energy Technology Data Exchange (ETDEWEB)

    1935-12-04

    A process is described for the treatment of distillable carbonaceous materials with hydrogen gases in the presence of hydrogen halides to recover valuable hydrocarbon products, characterized by the stable halide forming the treating medium for the hot-test gasesous product of this treatment with hydrogen gases in combination with an alkaline metal or alkaline earth, able to be decomposed by an inorganic acid soluble in water, capable of driving off hydrogen halide from their salts and also with salts of ammonia of the mentioned inorganic acids, the halide being converted into halide of ammonia and halogen, and the ammonia halide or hydrogen halide being returned to the process alone or together with the feed of carbonaceous materials with which it began.

  17. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, I.; Huppert, M.; Wörner, H. J., E-mail: hwoerner@ethz.ch [Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich (Switzerland); Brown, M. A. [Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, 8093 Zurich (Switzerland); Bokhoven, J. A. van [Institute for Chemical and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich (Switzerland); Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232 Villigen (Switzerland)

    2015-12-15

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup.

  18. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

    International Nuclear Information System (INIS)

    Jordan, I.; Huppert, M.; Wörner, H. J.; Brown, M. A.; Bokhoven, J. A. van

    2015-01-01

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup

  19. Photoelectron spectrometer for attosecond spectroscopy of liquids and gases

    Science.gov (United States)

    Jordan, I.; Huppert, M.; Brown, M. A.; van Bokhoven, J. A.; Wörner, H. J.

    2015-12-01

    A new apparatus for attosecond time-resolved photoelectron spectroscopy of liquids and gases is described. It combines a liquid microjet source with a magnetic-bottle photoelectron spectrometer and an actively stabilized attosecond beamline. The photoelectron spectrometer permits venting and pumping of the interaction chamber without affecting the low pressure in the flight tube. This pressure separation has been realized through a sliding skimmer plate, which effectively seals the flight tube in its closed position and functions as a differential pumping stage in its open position. A high-harmonic photon spectrometer, attached to the photoelectron spectrometer, exit port is used to acquire photon spectra for calibration purposes. Attosecond pulse trains have been used to record photoelectron spectra of noble gases, water in the gas and liquid states as well as solvated species. RABBIT scans demonstrate the attosecond resolution of this setup.

  20. Measurement of droplet vaporization rate enhancement caused by acoustic disturbances

    Science.gov (United States)

    Anderson, T. J.; Winter, M.

    1992-10-01

    Advanced laser diagnostics are being applied to quantify droplet vaporization enhancement in the presence of acoustic fields which can lead to instability in liquid-fueled rockets. While models have been developed to describe the interactions between subcritical droplet vaporization and acoustic fields in the surrounding gases, they have not been verified experimentally. In the super critical environment of a rocket engine combustor, little is understood about how the injected fluid is distributed. Experiments in these areas have been limited because of the lack of diagnostic techniques capable of providing quantitative results. Recently, however, extremely accurate vaporization rate measurements have been performed on droplets in a subcritical environment using morphology-dependent resonances (MDR's) in which fluorescence from an individual droplet provides information about its diameter. Initial measurements on methanol droplets behind a pressure pulse with a pressure ratio of 1.2 indicated that the evaporation rate in the first few microsec after wave passage was extremely high. Subsequent measurements have been made to validate these results using MDR's acquired from similarly-sized droplets using a pulse with a 1.1 pressure ratio. A baseline measurement was also made using a non evaporative fluid under similar Weber and Reynolds number conditions. The MDR technique employed for these measurements is explained and the facilities are described. The evaporation measurement results are shown and the rates observed from different droplet materials and different wave strengths are compared.

  1. Improved method for removing metal vapor from gas streams

    International Nuclear Information System (INIS)

    Ahluwalia, R.K.; Im, K.H.

    1994-01-01

    This invention relates to a process for gas cleanup to remove one or more metallic contaminants present as vapor. More particularly, the invention relates to a gas cleanup process using mass transfer to control the saturation levels such that essentially no particulates are formed, and the vapor condenses on the gas passage surfaces. It addresses the need to cleanup an inert gas contaminated with cadmium which may escape from the electrochemical processing of Integral Fast Reactor (IFR) fuel in a hot cell. The IFR is a complete, self-contained, sodium-cooled, pool-type fast reactor fueled with a metallic alloy of uranium, plutonium and zirconium, and is equipped with a close-coupled fuel cycle. Tests with a model have shown that removal of cadmium from argon gas is in the order of 99.99%. The invention could also apply to the industrial cleanup of air or other gases contaminated with zinc, lead, or mercury. In addition, the invention has application in the cleanup of other gas systems contaminated with metal vapors which may be toxic or unhealthy

  2. Lithium vapor/aerosol studies. Interim summary report

    International Nuclear Information System (INIS)

    Whitlow, G.A.; Bauerle, J.E.; Down, M.G.; Wilson, W.L.

    1979-04-01

    The temperature/cover gas pressure regime, in which detectable lithium aerosol is formed in a static system has been mapped for argon and helium cover gases using a portable He--Ne laser device. At 538 0 C (1000 0 F), lithium aerosol particles were observed over the range 0.5 to 20 torr and 2 to 10 torr for argon and helium respectively. The experimental conditions in this study were more conducive to aerosol formation than in a fusion reactor. In the real reactor system, very high intensity mechanical and thermal disturbances will be made to the liquid lithium. These disturbances, particularly transient increases in lithium vapor pressure appear to be capable of producing high concentrations of optically-dense aerosol. A more detailed study is, therefore, proposed using the basic information generated in these preliminary experiments, as a starting point. Areas recommended include the kinetics of aerosol formation and the occurrence of supersaturated vapor during rapid vapor pressure transients, and also the effect of lithium agitation (falls, jets, splashing, etc.) on aerosol formation

  3. Enhanced bulk heterojunction devices prepared by thermal and solvent vapor annealing processes

    Science.gov (United States)

    Forrest, Stephen R.; Thompson, Mark E.; Wei, Guodan; Wang, Siyi

    2017-09-19

    A method of preparing a bulk heterojunction organic photovoltaic cell through combinations of thermal and solvent vapor annealing are described. Bulk heterojunction films may prepared by known methods such as spin coating, and then exposed to one or more vaporized solvents and thermally annealed in an effort to enhance the crystalline nature of the photoactive materials.

  4. Gas Separation Using Organic-Vapor-Resistent Membranes In Conjunctin With Organic-Vapor-Selective Membranes

    Science.gov (United States)

    Baker, Richard W.; Pinnau, Ingo; He, Zhenjie; Da Costa, Andre R.; Daniels, Ramin; Amo, Karl D.; Wijmans, Johannes G.

    2003-06-03

    A process for treating a gas mixture containing at least an organic compound gas or vapor and a second gas, such as natural gas, refinery off-gas or air. The process uses two sequential membrane separation steps, one using membrane selective for the organic compound over the second gas, the other selective for the second gas over the organic vapor. The second-gas-selective membranes use a selective layer made from a polymer having repeating units of a fluorinated polymer, and demonstrate good resistance to plasticization by the organic components in the gas mixture under treatment, and good recovery after exposure to liquid aromatic hydrocarbons. The membrane steps can be combined in either order.

  5. Vapor pressures and vapor compositions in equilibrium with hypostoichiometric uranium-plutonium dioxide at high temperatures

    International Nuclear Information System (INIS)

    Green, D.W.; Fink, J.K.; Leibowitz, L.

    1982-01-01

    Vapor pressures and vapor compositions in equilibrium with a hypostoichiometric uranium-plutonium dioxide condensed phase (U/sub 1-y/Pu/sub y/)O/sub 2-x/, as functions of T, x, and y, have been calculated for 0.0 less than or equal to x less than or equal to 0.1, 0.0 less than or equal to y less than or equal to 0.3, and for the temperature range 2500 less than or equal to T less than or equal to 6000 K. The range of compositions and temperatures was limited to the region of interest to reactor safety analysis. Thermodynamic functions for the condensed phase and for each of the gaseous species were combined with an oxygen potential model to obtain partial pressures of O, O 2 , Pu, PuO, PuO 2 , U, UO, UO 2 , and UO 3 as functions of T, x, and y

  6. Stability limit of liquid water in metastable equilibrium with subsaturated vapors.

    Science.gov (United States)

    Wheeler, Tobias D; Stroock, Abraham D

    2009-07-07

    A pure liquid can reach metastable equilibrium with its subsaturated vapor across an appropriate membrane. This situation is analogous to osmotic equilibrium: the reduced chemical potential of the dilute phase (the subsaturated vapor) is compensated by a difference in pressure between the phases. To equilibrate with subsaturated vapor, the liquid phase assumes a pressure that is lower than its standard vapor pressure, such that the liquid phase is metastable with respect to the vapor phase. For sufficiently subsaturated vapors, the liquid phase can even assume negative pressures. The appropriate membrane for this metastable equilibrium must provide the necessary mechanical support to sustain the difference in pressure between the two phases, limit nonhomogeneous mechanisms of cavitation, and resist the entry of the dilutant (gases) into the pure phase (liquid). In this article, we present a study of the limit of stability of liquid water--the degree of subsaturation at which the liquid cavitates--in this metastable state within microscale voids embedded in hydrogel membranes. We refer to these structures as vapor-coupled voids (VCVs). In these VCVs, we observed that liquid water cavitated when placed in equilibrium with vapors of activity aw,vapairhumiditynucleation theory or molecular simulations (Pcav=-140 to -180 MPa). To determine the cause of the disparity between the observed and predicted stability limit, we examine experimentally the likelihood of several nonhomogeneous mechanisms of nucleation: (i) heterogeneous nucleation caused by hydrophobic patches on void walls, (ii) nucleation caused by the presence of dissolved solute, (iii) nucleation caused by the presence of pre-existing vapor nuclei, and (iv) invasion of air through the hydrogel membrane into the voids. We conclude that, of these possibilities, (i) and (ii) cannot be discounted, whereas (iii) and (iv) are unlikely to play a role in determining the stability limit.

  7. Greenhouse gases study in Amazonia

    International Nuclear Information System (INIS)

    D'Amelio, Monica Tais Siqueira

    2006-01-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO 2 sources. The Amazon forest is a significant source of N 2 O by soil process, and CH 4 by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO 2 , CH 4 , CO, H 2 , N 2 O and SF 6 have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO 2 flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO 2 flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H 2 gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO 2 sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that, in the 2004 and 2005 wet seasons and 2004 dry season comparison it was

  8. Dipolar quantum gases of erbium

    International Nuclear Information System (INIS)

    Frisch, A.

    2014-01-01

    Since the preparation of the first Bose-Einstein condensate about two decades ago and the first degenerate Fermi gas following four years later a plethora of fascinating quantum phenomena have been explored. The vast majority of experiments focused on quantum degenerate atomic gases with short-range contact interaction between particles. Atomic species with large magnetic dipole moments, such as chromium, dysprosium, and erbium, offer unique possibilities to investigate phenomena arising from dipolar interaction. This kind of interaction is not only long-range but also anisotropic in character and imprints qualitatively novel features on the system. Prominent examples are the d-wave collapse of a dipolar Bose-Einstein condensate of chromium atoms realized by the group in Stuttgart, the spin magnetization and demagnetization dynamics observed by groups in Stuttgart, Paris, and Stanford, and the deformation of the Fermi surface observed by our group in Innsbruck. This thesis reports on the creation and study of the first Bose-Einstein condensate and degenerate Fermi gas of erbium atoms. Erbium belongs to the lanthanide group of elements and has a large magnetic moment of seven Bohr magneton. In particular, this thesis describes the experimental apparatus and the sequence for producing a dipolar quantum gas. There is an emphasis on the production of the narrow-line magneto-optical trap of erbium since this represents a very efficient and robust laser-cooling scheme that greatly simplifies the experimental procedure. After describing the experimental setup this thesis focuses on several fundamental questions related to the dipolar character of erbium and to its lanthanide nature. A first set of studies centers on the scattering properties of ultracold erbium atoms, including the elastic and the inelastic cross section and the spectrum of Feshbach resonances. Specifically, we observe that identical dipolar fermions do collide and rethermalize even at low temperatures

  9. Thermodynamics of ultracold Fermi gases

    International Nuclear Information System (INIS)

    Nascimbene, Sylvain

    2010-01-01

    Complex Hamiltonians from condensed matter, such as the Fermi-Hubbard model, can be experimentally studied using ultracold gases. This thesis describes a new method for determining the equation of state of an ultracold gas, making the comparison with many-body theories straightforward. It is based on the measurement of the local pressure inside a trapped gas from the analysis of its in situ image. We first apply this method to the study of a Fermi gas with resonant interactions, a weakly-interacting 7 Li gas acting as a thermometer. Surprisingly, none of the existing many-body theories of the unitary gas accounts for the equation of state deduced from our study over its full range. The virial expansion extracted from the high-temperature data agrees with the resolution of the three-body problem. At low temperature, we observe, contrary to some previous studies, that the normal phase behaves as a Fermi liquid. Finally we obtain the critical temperature for superfluidity from a clear signature on the equation of state. We also measure the pressure of the ground state as a function of spin imbalance and interaction strength - measure directly relevant to describe the crust of neutron stars. Our data validate Monte-Carlo simulations and quantify the Lee-Huang-Yang corrections to mean-field interactions in low-density fermionic or bosonic superfluids. We show that, in most cases, the partially polarized normal phase can be described as a Fermi liquid of polarons. The polaron effective mass extracted from the equation of state is in agreement with a study of collective modes. (author)

  10. Rare gases in Samoan xenoliths

    Science.gov (United States)

    Poreda, R. J.; Farley, K. A.

    1992-09-01

    The rare gas isotopic compositions of residual harzburgite xenoliths from Savai'i (SAV locality) and an unnamed seamount south of the Samoan chain (PPT locality) provide important constraints on the rare gas evolution of the mantle and atmosphere. Despite heterogeneous trace element compositions, the rare gas characteristics of the xenoliths from each of the two localities are strikingly similar. SAV and PPT xenoliths have 3He/ 4He ratios of11.1 ± 0.5 R A and21.6 ± 1 R A, respectively; this range is comparable to the 3He/ 4He ratios in Samoan lavas and clearly demonstrates that they have trapped gases from a relatively undegassed reservoir. The neon results are not consistent with mixing between MORB and a plume source with an atmospheric signature. Rather, the neon isotopes reflect either a variably degassed mantle (with a relative order of degassing of Loihi Honda et al. that the 20Ne/ 22Ne ratio in the mantle more closely resembles the solar ratio than the atmospheric one. 40Ar/ 36Ar ratios in the least contaminated samples range from 4,000 to 12,000 with the highest values in the 22 RA PPT xenoliths. There is no evidence for atmospheric 40Ar/ 36Ar ratios in the mantle source of these samples, which indicates that the lower mantle may have 40Ar/ 36Ar ratios in excess of 5,000. Xenon isotopic anomalies in 129Xe and 136Xe are as high as 6%, or about half of the maximum MORB excess and are consistent with the less degassed nature of the Samoan mantle source. These results contradict previous suggestions that the high 3He/ 4He mantle has a near-atmospheric heavy rare gas isotopic composition.

  11. Synthesis of single walled carbon nanotubes by dual laser vaporization

    CSIR Research Space (South Africa)

    Moodley, MK

    2006-07-01

    Full Text Available Single walled carbon nanotubes were synthesized by the laser vaporization of graphite composite targets in a tube furnace. Two pulsed Nd:Yag lasers operating at fundamental (1064 nm) and 2 nd harmonic (532 nm) were combined, focused and evaporated...

  12. Investigating the Impact of Acetone Vapor Smoothing on the Strength and Elongation of Printed ABS Parts

    Science.gov (United States)

    Gao, Harry; Kaweesa, Dorcas V.; Moore, Jacob; Meisel, Nicholas A.

    2017-03-01

    Acetone vapor smoothing is a chemical treatment that "melts" the surface of additively manufactured acrylonitrile butadiene styrene parts. The process fuses layers together and allows them to reform when vapor is removed, resulting in a smooth surface finish. Although commonly used to improve aesthetics, recent work has begun to investigate the effects of vapor smoothing on part strength. Nevertheless, most of this work has failed to take into account the anisotropic nature of printed parts. Prior research has shown that vapor smoothing reduces strength under best-case loading conditions, when the tensile load is parallel with the direction of the layers. In this article, the authors hypothesize that vapor smoothing may increase strength under nonoptimal loading conditions as a result of increased cohesion between layers and a reduction in stress concentrations. They use a design of experiments approach to identify the combined impact of printing and vapor smoothing parameters on part material properties.

  13. Metal temperature monitoring in corrosive gases at high temperature and high thermal flows; Monitoreo de temperaturas de metal en gases corrosivos a alta temperatura y altos flujos termicos

    Energy Technology Data Exchange (ETDEWEB)

    Huerta Espino, Mario; Martinez Flores, Marco Antonio; Martinez Villafane, Alberto; Porcayo Calderon, Jesus; Gomez Guzman, Roberto; Reyes Cervantes, Fernando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    The direct measurement of metal temperatures during operation in superheater, reheater, and water wall tubes in zones exposed to high thermal flows is of great interest for the operation and analysis of the correct functioning of a steam generator. The operation temperature measurement of these zones differs very much of the monitored temperature in headers in the dead chamber, since the temperature measured in this zone is the steam temperature that does not reflect the one detected in the gas zone. For this reason, the thermocouples implant in gas zones will detect the real metal temperature and the incidence that some operation variables might have on it (Martinez et al., (1990). [Espanol] La medicion directa de temperaturas de metal durante operacion en tubos de sobrecalentador, recalentador y pared de agua en zonas expuestas a altos flujos termicos es de gran interes para la operacion y analisis del buen funcionamiento de un generador de vapor. La medicion de la temperatura de operacion de estas zonas, difiere mucho de la temperatura monitoreada en cabezales en zona de camara muerta, ya que la temperatura registrada en esta zona es la de vapor que no es un reflejo de la detectada en zona de gases. Por esta razon, la implantacion de termopares en zona de gases detectara la temperatura de metal real y la incidencia que algunas variables de operacion tengan sobre esta (Martinez et al., 1990).

  14. Metal temperature monitoring in corrosive gases at high temperature and high thermal flows; Monitoreo de temperaturas de metal en gases corrosivos a alta temperatura y altos flujos termicos

    Energy Technology Data Exchange (ETDEWEB)

    Huerta Espino, Mario; Martinez Flores, Marco Antonio; Martinez Villafane, Alberto; Porcayo Calderon, Jesus; Gomez Guzman, Roberto; Reyes Cervantes, Fernando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1991-12-31

    The direct measurement of metal temperatures during operation in superheater, reheater, and water wall tubes in zones exposed to high thermal flows is of great interest for the operation and analysis of the correct functioning of a steam generator. The operation temperature measurement of these zones differs very much of the monitored temperature in headers in the dead chamber, since the temperature measured in this zone is the steam temperature that does not reflect the one detected in the gas zone. For this reason, the thermocouples implant in gas zones will detect the real metal temperature and the incidence that some operation variables might have on it (Martinez et al., (1990). [Espanol] La medicion directa de temperaturas de metal durante operacion en tubos de sobrecalentador, recalentador y pared de agua en zonas expuestas a altos flujos termicos es de gran interes para la operacion y analisis del buen funcionamiento de un generador de vapor. La medicion de la temperatura de operacion de estas zonas, difiere mucho de la temperatura monitoreada en cabezales en zona de camara muerta, ya que la temperatura registrada en esta zona es la de vapor que no es un reflejo de la detectada en zona de gases. Por esta razon, la implantacion de termopares en zona de gases detectara la temperatura de metal real y la incidencia que algunas variables de operacion tengan sobre esta (Martinez et al., 1990).

  15. Trends of total water vapor column above the Arctic from satellites observations

    Science.gov (United States)

    Alraddawi, Dunya; Sarkissian, Alain; Keckhut, Philippe; Bock, Olivier; Claud, Chantal; Irbah, Abdenour

    2016-04-01

    Atmospheric water vapor (H2O) is the most important natural (as opposed to man-made) greenhouse gas, accounting for about two-thirds of the natural greenhouse effect. Despite this importance, its role in climate and its reaction to climate change are still difficult to assess. Many details of the hydrological cycle are poorly understood, such as the process of cloud formation and the transport and release of latent heat contained in the water vapor. In contrast to other important greenhouse gases like carbon dioxide (CO2) and methane, water vapor has a much higher temporal and spatial variability. Total precipitable water (TPW) or the total column of water vapor (TCWV) is the amount of liquid water that would result if all the water vapor in the atmospheric column of unit area were condensed. TCWV distribution contains valuable information on the vigor of the hydrological processes and moisture transport in the atmosphere. Measurement of TPW can be obtained based on atmospheric water vapor absorption or emission of radiation in the spectral range from UV to MW. TRENDS were found over the terrestrial Arctic by means of TCWV retrievals (using Moderate Resolution Imaging Spectro-radiometer (MODIS) near-infrared (2001-2015) records). More detailed approach was made for comparisons with ground based instruments over Sodankyla - Finland (TCWV from: SCIAMACHY 2003-2011, GOME-2A 2007-2011, SAOZ 2003-2011, GPS 2003-2011, MODIS 2003-2011)

  16. Influence of the gray gases number in the weighted sum of gray gases model on the radiative heat exchange calculation inside pulverized coal-fired furnaces

    Directory of Open Access Journals (Sweden)

    Crnomarković Nenad Đ.

    2016-01-01

    Full Text Available The influence of the number of gray gases in the weighted sum in the gray gases model on the calculation of the radiative heat transfer is discussed in the paper. A computer code which solved the set of equations of the mathematical model describing the reactive two-phase turbulent flow with radiative heat exchange and with thermal equilibrium between phases inside the pulverized coal-fired furnace was used. Gas-phase radiative properties were determined by the simple gray gas model and two combinations of the weighted sum of the gray gases models: one gray gas plus a clear gas and two gray gases plus a clear gas. Investigation was carried out for two values of the total extinction coefficient of the dispersed phase, for the clean furnace walls and furnace walls covered by an ash layer deposit, and for three levels of the approximation accuracy of the weighting coefficients. The influence of the number of gray gases was analyzed through the relative differences of the wall fluxes, wall temperatures, medium temperatures, and heat transfer rate through all furnace walls. The investigation showed that there were conditions of the numerical investigations for which the relative differences of the variables describing the radiative heat exchange decrease with the increase in the number of gray gases. The results of this investigation show that if the weighted sum of the gray gases model is used, the complexity of the computer code and calculation time can be reduced by optimizing the number of gray gases. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in-house developed software tools

  17. Vapor plume oscillation mechanisms in transient keyhole during tandem dual beam fiber laser welding

    Science.gov (United States)

    Chen, Xin; Zhang, Xiaosi; Pang, Shengyong; Hu, Renzhi; Xiao, Jianzhong

    2018-01-01

    Vapor plume oscillations are common physical phenomena that have an important influence on the welding process in dual beam laser welding. However, until now, the oscillation mechanisms of vapor plumes remain unclear. This is primarily because mesoscale vapor plume dynamics inside a millimeter-scale, invisible, and time-dependent keyhole are difficult to quantitatively observe. In this paper, based on a developed three-dimensional (3D) comprehensive model, the vapor plume evolutions in a dynamical keyhole are directly simulated in tandem dual beam, short-wavelength laser welding. Combined with the vapor plume behaviors outside the keyhole observed by high-speed imaging, the vapor plume oscillations in dynamical keyholes at different inter-beam distances are the first, to our knowledge, to be quantitatively analyzed. It is found that vapor plume oscillations outside the keyhole mainly result from vapor plume instabilities inside the keyhole. The ejection velocity at the keyhole opening and dynamical behaviors outside the keyhole of a vapor plume both violently oscillate with the same order of magnitude of high frequency (several kHz). Furthermore, the ejection speed at the keyhole opening and ejection area outside the keyhole both decrease as the beam distance increases, while the degree of vapor plume instability first decreases and then increases with increasing beam distance from 0.6 to 1.0 mm. Moreover, the oscillation mechanisms of a vapor plume inside the dynamical keyhole irradiated by dual laser beams are investigated by thoroughly analyzing the vapor plume occurrence and flow process. The vapor plume oscillations in the dynamical keyhole are found to mainly result from violent local evaporations and severe keyhole geometry variations. In short, the quantitative method and these findings can serve as a reference for further understanding of the physical mechanisms in dual beam laser welding and of processing optimizations in industrial applications.

  18. Techniques for the measurement of trace moisture in high-purity electronic specialty gases

    International Nuclear Information System (INIS)

    Funke, Hans H.; Grissom, Brad L.; McGrew, Clark E.; Raynor, Mark W.

    2003-01-01

    The control of water vapor (moisture) contamination in process gases is critical to the successful manufacture of semiconductor devices. As specified moisture levels have become more stringent, there is a growing demand for more sensitive analytical methods. Instrumental methods currently being used or in development for measuring trace moisture at ppbv levels include Fourier transform infrared spectroscopy, tunable diode laser absorption spectroscopy, cavity ringdown spectroscopy, intracavity laser spectroscopy, electron impact ionization mass spectrometry, and atmospheric pressure ionization mass spectrometry. In addition, sensor-based technologies such as oscillating quartz crystal microbalances, and chilled mirror-, capacitor-, and electrolytic-based hygrometers operate in this regime. These approaches are presented and reviewed. As the success of each trace moisture method is dependent on the degree to which the different process gases interfere with the measurement process, important process gas applications of the techniques are highlighted. Advantages and disadvantages as well as future developments and trends are also presented

  19. Molecular simulation of water removal from simple gases with zeolite NaA.

    Science.gov (United States)

    Csányi, Eva; Ható, Zoltán; Kristóf, Tamás

    2012-06-01

    Water vapor removal from some simple gases using zeolite NaA was studied by molecular simulation. The equilibrium adsorption properties of H(2)O, CO, H(2), CH(4) and their mixtures in dehydrated zeolite NaA were computed by grand canonical Monte Carlo simulations. The simulations employed Lennard-Jones + Coulomb type effective pair potential models, which are suitable for the reproduction of thermodynamic properties of pure substances. Based on the comparison of the simulation results with experimental data for single-component adsorption at different temperatures and pressures, a modified interaction potential model for the zeolite is proposed. In the adsorption simulations with mixtures presented here, zeolite exhibits extremely high selectivity of water to the investigated weakly polar/non-polar gases demonstrating the excellent dehydration ability of zeolite NaA in engineering applications.

  20. Vesicles in Apollo 15 Green Glasses: The Nature of Ancient Lunar Gases

    Science.gov (United States)

    Thomas-Keprta, K. L.; Clemett, S. J.; Berger, E. L.; Rahman, Z.; McKay, D. S.; Gibson, E. K.; Wentworth, S. J.

    2014-01-01

    Detailed studies of Apollo 15 green glass and related beads have shown they were formed in gas-rich fire fountains.. As the magmatic fluid became super-saturated in volatile gas, bubbles or vesicles formed within the magma. These exsolved gases became trapped within vesicles as the glasses were ejected from the fire-fountain and subsequently quenched. One of the keys to understanding formation processes on the ancient moon includes determining the composition of volatile species and elements, including metals, dissolved in magmatic gases. Here we report the nature of mineral phases spatially associated with vesicles in a green glass bead from Apollo sample 15411,42. The phases reflect the composition of the cooling/degassing magmatic vapors and fluids present at the time of bead formation approx, 3 Ga ago

  1. Spectroscopic Diagnostics of Barrier Discharge Plasmas in Mixtures of Zinc Diiodide with Inert Gases

    International Nuclear Information System (INIS)

    Guivan, N.N.; Malinin, A.N.

    2005-01-01

    The spectral characteristics of the emission of gas discharge atmospheric pressure plasmas in mixtures of zinc diiodide vapor with inert gases (He, Ne, Ar, Kr, and Xe) are investigated. The formation of a gas discharge plasma and the excitation of the components of a working mixture were performed in a high-frequency (with a repetition frequency of sinusoidal voltage pulses of 100 kHz) barrier discharge. The gas discharge emission was analyzed in the spectral range 200-900 nm with a resolution of 0.05 nm. Emission bands of ZnI(B-X) exciplex molecules and I* 2 excimer molecules, lines of inert gases, and emission bands of XeI* exciplex molecules (in Xe-containing mixtures) were revealed. It is ascertained that the strongest emission of ZnI* molecules is observed in ZnI 2 /He(Ne) mixtures. The regularities in the spectral characteristics of the gas discharge plasma emission are considered

  2. Anaesthetic gases: environmental impact and alternatives

    African Journals Online (AJOL)

    Little consideration has been given to the environmental impact of anaesthetic gas .... our practice to select gases with a lower environmental impact is also ... is used as raw material for new anaesthetics. ... none in the pipeline.1. Conclusion.

  3. Voluntary reporting of greenhouse gases, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  4. Granular Gases: Probing the Boundaries of Hydrodynamics

    International Nuclear Information System (INIS)

    Goldhirsch, I.

    1999-01-01

    The dissipative nature of the particle interactions in granular systems renders granular gases mesoscopic and bearing some similarities to regular gases in the ''continuum transition regime'' where shear rates and/or thermal gradients are very large). The following properties of granular gases support the above claim: (i). Mean free times are of the same order as macroscopic time scales (inverse shear rates); (ii). Mean free paths can be macroscopic and comparable to the system's dimensions; (iii). Typical flows are supersonic; (iv). Shear rates are typically ''large''; (v). Stress fields are scale (resolution) dependent; (vi). Burnett and super-Burnett corrections to both the constitutive relations and the boundary conditions are of importance; (vii). Single particle distribution functions can be far from Gaussian. It is concluded that while hydrodynamic descriptions of granular gases are relevant, they are probing the boundaries of applicability of hydrodynamics and perhaps slightly beyond

  5. Greenhouse gases - observed tendencies contra scenarios

    International Nuclear Information System (INIS)

    Groenaas, Sigbjoern

    2006-01-01

    The article presents a study of the increase in greenhouse gases and concludes that it will be necessary to substantially reduce the CO2 concentrations in the atmosphere in order to avoid serious climatic changes

  6. Climate Change, Greenhouse Gases and Aerosols

    Indian Academy of Sciences (India)

    user

    their radiative properties are similar to the glass used in a green- house. Greenhouse gases in the Earth's atmosphere absorb 90% of the radiation emitted .... and wind speed and direction in each box is calculated using the physical laws gov-.

  7. Roadside management strategies to reduce greenhouse gases.

    Science.gov (United States)

    2010-06-01

    Californias Global Warming Solutions Act of 2006 (AB 32), Sustainable Communities and Climate Protection Act : (SB 375), and Executive Order S-14-08 direct Caltrans to develop actions to reduce greenhouse gases (GHGs). Air : pollution reduction is...

  8. Thermal Oxidation of Tail Gases from the Production of Oil-furnace Carbon Black

    Directory of Open Access Journals (Sweden)

    Bosak, Z.

    2009-01-01

    Full Text Available This paper describes the production technology of oil-furnace carbon black, as well as the selected solution for preventing the emissions of this process from contaminating the environment.The products of industrial oil-furnace carbon black production are different grades of carbon black and process tail gases. The qualitative composition of these tail gases during the production of oil-furnace carbon black are: carbon(IV oxide, carbon(II oxide, hydrogen, methane, hydrogen sulfide, nitrogen, oxygen, and water vapor.The quantitative composition and lower caloric value of process tail gases change depending on the type of feedstock used in the production, as well as the type of process. The lower caloric value of process tail gases is relatively small with values ranging between 1500 and 2300 kJ m–3.In the conventional production of oil-furnace carbon black, process tail gases purified from carbon black dust are freely released into the atmosphere untreated. In this manner, the process tail gases pollute the air in the town of Kutina, because their quantitative values are much higher than the prescribed emissions limits for hydrogen sulfide and carbon(II oxide. A logical solution for the prevention of such air pollution is combustion of the process tail gases, i. e. their thermal oxidation. For this purpose, a specially designed flare system has been developed. Consuming minimum amounts of natural gas needed for oxidation, the flare system is designed to combust low caloric process tail gases with 99 % efficiency. Thus, the toxic and flammable components of the tail gases (hydrogen sulfide, hydrogen, carbon(II oxide, methane and other trace hydrocarbons would be transformed into environmentally acceptable components (sulfur(IV oxide, water, carbon(IV oxide and nitrogen(IV oxide, which are in compliance with the emissions limit values prescribed by law.Proper operation of this flare system in the production of oil-furnace carbon black would solve

  9. Water vapor as a perspective coolant for fast reactors

    International Nuclear Information System (INIS)

    Kalafati, D.D.; Petrov, S.I.

    1978-01-01

    Based on analysis of foreign projects of nuclear power plants with steam-cooled fast reactors, it is shown that low breeding ratio and large doubling time were caused by using nickel alloys, high vapor pressure and small volume heat release. The possibility is shown of obtaining doubling time in the necessary limits of T 2 =10-12 years when the above reasons for steam-cooled reactors are eliminated. Favourable combination of thermophysical and thermodynamic properties of water vapor makes it perspective coolant for power fast reactors

  10. Gases for an SSC muon detector

    International Nuclear Information System (INIS)

    Christophorou, L.G.; Datskos, P.G.; Carter, J.G.; Tennessee Univ., Knoxville, TN

    1990-01-01

    Recent measurements of electron drift velocities as a function of the density-reduced electric field E/N are reported for a number of unitary gases and the mixtures CO 2 /CH 4 and NH 3 /CF 4 /Ar. Calculated values of the mean electron energy as a function of E/N are also reported for unitary gases and mixtures of CO 2 /CH 4 . 7 refs., 5 figs

  11. Flux Jacobian Matrices For Equilibrium Real Gases

    Science.gov (United States)

    Vinokur, Marcel

    1990-01-01

    Improved formulation includes generalized Roe average and extension to three dimensions. Flux Jacobian matrices derived for use in numerical solutions of conservation-law differential equations of inviscid flows of ideal gases extended to real gases. Real-gas formulation of these matrices retains simplifying assumptions of thermodynamic and chemical equilibrium, but adds effects of vibrational excitation, dissociation, and ionization of gas molecules via general equation of state.

  12. Pseudogap phenomena in ultracold atomic Fermi gases

    OpenAIRE

    Chen, Qijin; Wang, Jibiao

    2014-01-01

    The pairing and superfluid phenomena in a two-component ultracold atomic Fermi gas is an analogue of Cooper pairing and superconductivity in an electron system, in particular, the high $T_c$ superconductors. Owing to the various tunable parameters that have been made accessible experimentally in recent years, atomic Fermi gases can be explored as a prototype or quantum simulator of superconductors. It is hoped that, utilizing such an analogy, the study of atomic Fermi gases may shed light to ...

  13. Liquid-vapor equilibrium and interfacial properties of square wells in two dimensions

    Science.gov (United States)

    Armas-Pérez, Julio C.; Quintana-H, Jacqueline; Chapela, Gustavo A.

    2013-01-01

    Liquid-vapor coexistence and interfacial properties of square wells in two dimensions are calculated. Orthobaric densities, vapor pressures, surface tensions, and interfacial thicknesses are reported. Results are presented for a series of potential widths λ* = 1.4, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5, where λ* is given in units of the hard core diameter σ. Critical and triple points are explored. No critical point was found for λ* Armas-Pérez et al. [unpublished] as a hexatic phase transition. It is located at reduced temperatures T* = 0.47 and 0.35 for λ* = 1.4 and 1.5, respectively. Properties such as the surface tension, vapor pressure, and interfacial thickness do not present any discontinuity at these points. This amorphous solid branch does not follow the corresponding state principle, which is only applied to liquids and gases.

  14. A Review on Graphene-Based Gas/Vapor Sensors with Unique Properties and Potential Applications

    Institute of Scientific and Technical Information of China (English)

    Tao Wang; Da Huang; Zhi Yang; Shusheng Xu; Guili He; Xiaolin Li; Nantao Hu; Guilin Yin; Dannong He; Liying Zhang

    2016-01-01

    Graphene-based gas/vapor sensors have attracted much attention in recent years due to their variety of structures, unique sensing performances, room-temperature working conditions, and tremendous application prospects, etc.Herein, we summarize recent advantages in graphene preparation, sensor construction, and sensing properties of various graphene-based gas/vapor sensors, such as NH3, NO2, H2, CO, SO2, H2S, as well as vapor of volatile organic compounds.The detection mechanisms pertaining to various gases are also discussed. In conclusion part, some existing problems which may hinder the sensor applications are presented. Several possible methods to solve these problems are proposed, for example, conceived solutions, hybrid nanostructures, multiple sensor arrays, and new recognition algorithm.

  15. Modeling of a diode-pumped thin-disk cesium vapor laser

    Science.gov (United States)

    An, Guofei; Cai, He; Liu, Xiaoxu; Han, Juhong; Zhang, Wei; Wang, Hongyuan; Wang, You

    2018-03-01

    A diode pumped alkali laser (DPAL) provides a significant potential for construction of high-powered lasers. Until now, a series of models have been established to analyze the kinetic process and most of them are based on the end-pumped alkali laser system in which the vapor cell are usually cylindrical and cuboid. In this paper, a mathematic model is constructed to investigate the kinetic processes of a diode pumped thin-disk cesium vapor laser, in which the cesium vapor and the buffer gases are beforehand filled in a sealed glass cell with a thin-disk structure. We systemically study the influences of the cell temperature and cell thickness on the output features of a thin-disk DPAL. Further, we study the thin-disk DPAL with the W-shaped resonator and multiple-disk configuration. To the best of our knowledge, there have not been any similar reports so far.

  16. Characterization of a clock based on coherent population trapping in a thermal cesium vapor. Main effects that may affect its mid- and long-term frequency stability

    International Nuclear Information System (INIS)

    Kozlova, Olga

    2013-01-01

    This thesis describes a Cs - buffer gas vapor cell atomic clock based on coherent population trapping (CPT), and the main frequency shifts affecting its mid- and long-term stability. The developed atomic clock based on CPT uses two original techniques: a so-called double-Λ scheme for the CPT-resonance excitation and a temporal Ramsey interrogation technique, which produce a high contrast and narrow resonances with reduced light shift dependence. Generally, the mid and long term stability of the vapor cell atomic clock is limited by the collisional shift induced by alkali-buffer gas collisions and the light shift (or the effects depending on the laser intensity). We report on the study of the collisional shift of Cs clock frequency in the presence of Ne, N 2 or Ar buffer gas, and its temperature dependence. The coefficient values of this dependence for these three buffer gases were revealed (some of them for the first time), allowing us to realise a cell with optimal combination of buffer gases to cancel the temperature dependence around the working temperature. Following the study of the signal amplitude and the coherence relaxation rate the optimal values for such parameters as interrogation cycle, magnetic field, cell temperature, pressure of the buffer gas mixture, etc. were found for the chosen cell. The investigation on the light shift and the effects depending on the laser intensity allowed us to determine the most sensitive parameters (laser intensity ratio, temperature) and to implement the required stabilizations in order to better control them. Finally, the mid- and long-term clock frequency stability was improved by a factor 40, reaching 2.5 10 -14 at 1 hour. (author)

  17. Recent Experimental Advances to Determine (noble) Gases in Waters

    Science.gov (United States)

    Kipfer, R.; Brennwald, M. S.; Huxol, S.; Mächler, L.; Maden, C.; Vogel, N.; Tomonaga, Y.

    2013-12-01

    In aquatic systems noble gases, radon, and bio-geochemically conservative transient trace gases (SF6, CFCs) are frequently applied to determine water residence times and to reconstruct past environmental and climatic conditions. Recent experimental breakthroughs now enable ● to apply the well-established concepts of terrestrial noble gas geochemistry in waters to the minute water amounts stored in sediment pore space and in fluid inclusions (A), ● to determine gas exchange processes on the bio-geochemical relevant time scales of minutes - hours (B), and ● to separate diffusive and advective gas transport in soil air (C). A. Noble-gas analysis in water samples (transport in the pore space and identifying the origin of bio- and geogenic fluids in (un) consolidated sediments [1]. Advanced techniques that combine crushing and sieving speleothem samples in ultra-high-vacuum to a specific grain size allow to separate air and water-bearing fluid inclusions and thus enables noble-gas-based reconstruction of environmental conditions from water masses as small as 1mg [2]. B. The coupling of noble gas analysis with approaches of gas chromatography permits combined analysis of noble gases and other gases species (e.g., SF6, CFCs, O2, N2) from a single water sample. The new method substantially improves ground water dating by SF6 and CFCs as excess air is quantified from the same sample and hence can adequately be corrected for [3]. Portable membrane-inlet mass spectrometers enable the quasi-continuous and real-time analysis of noble gases and other dissolved gases directly in the field, allowing, for instance, quantification of O2 turnover rates on small time scales [4]. C. New technical developments perfect 222Rn analysis in water by the synchronous the determination of the short-lived 220Rn. The combined 220,222Rn analysis sheds light on the emanation behaviour of radon by identifying soil water content to be the crucial control of 220Rn occurrence in the environment

  18. Method of controlling a distillatory coulumn in a liquefaction and distillation device for radioactive rare gases

    International Nuclear Information System (INIS)

    Kimura, Shigeru; Awata, Yoshihisa.

    1975-01-01

    Object: To automatically and securely perform controlling purity of column bottom liquid, which is most difficult in the liquefaction and distillation device. Structure: In a liquefaction and distillation device for liquefying and separating rare gas krypton in fuel reprocessing gases, a difference in temperature between the column bottom liquid (column top) and the distillation portion is detected so as to maintain temperature in the distillation portion of the distilling column constant, and the vaporization amount of column bottom liquid is varied with the difference in temperature to control purity of the column bottom liquid. (Kamimura, M.)

  19. Analysis of electron interactions in dielectric gases

    International Nuclear Information System (INIS)

    Olivet, Aurelio; Duque, Daniel; Vega, Lourdes F.

    2007-01-01

    We present and discuss results concerning electron interactions processes of dielectric gases and their relationship with the macroscopic behavior of these gases, in particular, with their dielectric strength. Such analysis is based on calculating energies of reactions for molecular ionization, dissociative ionization, parent negative ion formation, and dissociative electron attachment processes. We hypothesize that the estimation of the required energy for a reduced number of processes that take place in electrically stressed gases could be related to the gas' capability to manage the electron flow during an electrical discharge. All calculations were done with semiempirical quantum chemistry methods, including an initial optimization of molecular geometry and heat of formation of the dielectric gases and all of species that appear during electron interaction reactions. The performance of semiempirical methods Austin model 1 and Parametric model 3 (PM3) was compared for several compounds, PM3 being superior in most cases. Calculations performed for a sample of nine dielectric gases show that electron attachment and detachment processes occur in different energy bands that do not overlap for any value of the dielectric strength. We have also analyzed the relationship between dielectric strength and two physical properties: electron affinity and ionization energy. Calculations performed for 43 dielectric gases show no clear correlation between them, although certain guidelines for the qualitative estimation of dielectric strength can still be assessed

  20. Gases and carbon in metals. Pt. 14

    International Nuclear Information System (INIS)

    Jehn, H.; Speck, H.; Hehn, W.; Fromm, E.; Hoerz, G.

    1981-01-01

    This issue is part of a series of data on 'Gases and Carbon in Metals' which supplements the data compilation in the book 'Gase und Kohlenstoff in Metallen' (Gases and Carbon in Metals), edited by E. Fromm and E. Gebhardt, Springer-Verlag, Berlin 1976. The present survey includes results from papers published after the copy deadline and recommends critically selected data. Furthermore, it comprises a bibliography of relevant literature. For each element, firstly data on binary systems are presented, starting with hydrogen and followed by carbon, nitrogen, oxygen, and rare gases. Within one metal-metalloid system the data are listed under topics such as solubility, solubility limit, dissociation pressure of compounds, vapour pressure of volatile oxides, thermodynamic data, diffusion, transport parameters (effective valence, heat of transport), permeation of gases through metals, gas absorption and gas desorption kinetics, compound formation kinetics, precipitation kinetics, and property changes. Following the data on binary systems, the data of ternary systems are presented, beginning with systems which contain one metal and two gases or one gas and carbon and continuing with systems with two metals and one gas or carbon. (orig./GE)

  1. Thermal plasma chemical vapor deposition

    International Nuclear Information System (INIS)

    Heberlein, J.; Pfender, E.

    1993-01-01

    Thermal plasmas, with temperatures up to and even exceeding 10 4 K, are capable of producing high density vapor phase precursors for the deposition of relatively thick films. Although this technology is still in its infancy, it will fill the void between the relatively slow deposition processes such as physical vapor deposition and the high rate thermal spray deposition processes. In this chapter, the present state-of-the-art of this field is reviewed with emphasis on the various types of reactors proposed for this emerging technology. Only applications which attracted particular attention, namely diamond and high T c superconducting film deposition, are discussed in greater detail. (orig.)

  2. High-accuracy continuous airborne measurements of greenhouse gases (CO2 and CH4) during BARCA

    Science.gov (United States)

    Chen, H.; Winderlich, J.; Gerbig, C.; Hoefer, A.; Rella, C. W.; Crosson, E. R.; van Pelt, A. D.; Steinbach, J.; Kolle, O.; Beck, V.; Daube, B. C.; Gottlieb, E. W.; Chow, V. Y.; Santoni, G. W.; Wofsy, S. C.

    2009-12-01

    High-accuracy continuous measurements of greenhouse gases (CO2 and CH4) during the BARCA (Balanço Atmosférico Regional de Carbono na Amazônia) phase B campaign in Brazil in May 2009 were accomplished using a newly available analyzer based on the cavity ring-down spectroscopy (CRDS) technique. This analyzer was flown without a drying system or any in-flight calibration gases. Water vapor corrections associated with dilution and pressure-broadening effects for CO2 and CH4 were derived from laboratory experiments employing measurements of water vapor by the CRDS analyzer. Before the campaign, the stability of the analyzer was assessed by laboratory tests under simulated flight conditions. During the campaign, a comparison of CO2 measurements between the CRDS analyzer and a nondispersive infrared (NDIR) analyzer on board the same aircraft showed a mean difference of 0.22±0.09 ppm for all flights over the Amazon rain forest. At the end of the campaign, CO2 concentrations of the synthetic calibration gases used by the NDIR analyzer were determined by the CRDS analyzer. After correcting for the isotope and the pressure-broadening effects that resulted from changes of the composition of synthetic vs. ambient air, and applying those concentrations as calibrated values of the calibration gases to reprocess the CO2 measurements made by the NDIR, the mean difference between the CRDS and the NDIR during BARCA was reduced to 0.05±0.09 ppm, with the mean standard deviation of 0.23±0.05 ppm. The results clearly show that the CRDS is sufficiently stable to be used in flight without drying the air or calibrating in flight and the water corrections are fully adequate for high-accuracy continuous airborne measurements of CO2 and CH4.

  3. Quantum statistics of dense gases and nonideal plasmas

    CERN Document Server

    Ebeling, Werner; Filinov, Vladimir

    2017-01-01

    The aim of this book is the pedagogical exploration of the basic principles of quantum-statistical thermodynamics as applied to various states of matter – ranging from rare gases to astrophysical matter with high-energy density. The reader will learn in this work that thermodynamics and quantum statistics are still the concepts on which even the most advanced research is operating - despite of a flood of modern concepts, classical entities like temperature, pressure, energy and entropy are shown to remain fundamental. The physics of gases, plasmas and high-energy density matter is still a growing field and even though solids and liquids dominate our daily life, more than 99 percent of the visible Universe is in the state of gases and plasmas and the overwhelming part of matter exists at extreme conditions connected with very large energy densities, such as in the interior of stars. This text, combining material from lectures and advanced seminars given by the authors over many decades, is a must-have intr...

  4. Trajectory mapping of middle atmospheric water vapor by a mini network of NDACC instruments

    Directory of Open Access Journals (Sweden)

    M. Lainer

    2015-08-01

    Full Text Available The important task to observe the global coverage of middle atmospheric trace gases like water vapor or ozone usually is accomplished by satellites. Climate and atmospheric studies rely upon the knowledge of trace gas distributions throughout the stratosphere and mesosphere. Many of these gases are currently measured from satellites, but it is not clear whether this capability will be maintained in the future. This could lead to a significant knowledge gap of the state of the atmosphere. We explore the possibilities of mapping middle atmospheric water vapor in the Northern Hemisphere by using Lagrangian trajectory calculations and water vapor profile data from a small network of five ground-based microwave radiometers. Four of them are operated within the frame of NDACC (Network for the Detection of Atmospheric Composition Change. Keeping in mind that the instruments are based on different hardware and calibration setups, a height-dependent bias of the retrieved water vapor profiles has to be expected among the microwave radiometers. In order to correct and harmonize the different data sets, the Microwave Limb Sounder (MLS on the Aura satellite is used to serve as a kind of traveling standard. A domain-averaging TM (trajectory mapping method is applied which simplifies the subsequent validation of the quality of the trajectory-mapped water vapor distribution towards direct satellite observations. Trajectories are calculated forwards and backwards in time for up to 10 days using 6 hourly meteorological wind analysis fields. Overall, a total of four case studies of trajectory mapping in different meteorological regimes are discussed. One of the case studies takes place during a major sudden stratospheric warming (SSW accompanied by the polar vortex breakdown; a second takes place after the reformation of stable circulation system. TM cases close to the fall equinox and June solstice event from the year 2012 complete the study, showing the high

  5. Waste Tank Vapor Project: Tank vapor database development

    International Nuclear Information System (INIS)

    Seesing, P.R.; Birn, M.B.; Manke, K.L.

    1994-09-01

    The objective of the Tank Vapor Database (TVD) Development task in FY 1994 was to create a database to store, retrieve, and analyze data collected from the vapor phase of Hanford waste tanks. The data needed to be accessible over the Hanford Local Area Network to users at both Westinghouse Hanford Company (WHC) and Pacific Northwest Laboratory (PNL). The data were restricted to results published in cleared reports from the laboratories analyzing vapor samples. Emphasis was placed on ease of access and flexibility of data formatting and reporting mechanisms. Because of time and budget constraints, a Rapid Application Development strategy was adopted by the database development team. An extensive data modeling exercise was conducted to determine the scope of information contained in the database. a A SUN Sparcstation 1000 was procured as the database file server. A multi-user relational database management system, Sybase reg-sign, was chosen to provide the basic data storage and retrieval capabilities. Two packages were chosen for the user interface to the database: DataPrism reg-sign and Business Objects trademark. A prototype database was constructed to provide the Waste Tank Vapor Project's Toxicology task with summarized and detailed information presented at Vapor Conference 4 by WHC, PNL, Oak Ridge National Laboratory, and Oregon Graduate Institute. The prototype was used to develop a list of reported compounds, and the range of values for compounds reported by the analytical laboratories using different sample containers and analysis methodologies. The prototype allowed a panel of toxicology experts to identify carcinogens and compounds whose concentrations were within the reach of regulatory limits. The database and user documentation was made available for general access in September 1994

  6. Geostationary Satellite Observation of Precipitable Water Vapor Using an Empirical Orthogonal Function (EOF based Reconstruction Technique over Eastern China

    Directory of Open Access Journals (Sweden)

    Man Sing Wong

    2015-05-01

    Full Text Available Water vapor, as one of the most important greenhouse gases, is crucial for both climate and atmospheric studies. Considering the high spatial and temporal variations of water vapor, a timely and accurate retrieval of precipitable water vapor (PWV is urgently needed, but has long been constrained by data availability. Our study derived the vertically integrated precipitable water vapor over eastern China using Multi-functional Transport Satellite (MTSAT data, which is in geostationary orbit with high temporal resolution. The missing pixels caused by cloud contamination were reconstructed using an Empirical Orthogonal Function (EOF decomposition method over both spatial and temporal dimensions. GPS meteorology data were used to validate the retrieval and the reconstructed results. The diurnal variation of PWV over eastern China was analyzed using harmonic analysis, which indicates that the reconstructed PWV data can depict the diurnal cycle of PWV caused by evapotranspiration and local thermal circulation.

  7. Estimated vapor pressure for WTP process streams

    Energy Technology Data Exchange (ETDEWEB)

    Pike, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Poirier, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-01-01

    Design assumptions during the vacuum refill phase of the Pulsed Jet Mixers (PJMs) in the Hanford Waste Treatment and Immobilization Plant (WTP) equate the vapor pressure of all process streams to that of water when calculating the temperature at which the vacuum refill is reduced or eliminated. WTP design authority asked the authors to assess this assumption by performing calculations on proposed feed slurries to calculate the vapor pressure as a function of temperature. The vapor pressure was estimated for each WTP waste group. The vapor pressure suppression caused by dissolved solids is much greater than the increase caused by organic components such that the vapor pressure for all of the waste group compositions is less than that of pure water. The vapor pressure for each group at 145°F ranges from 81% to 98% of the vapor pressure of water. If desired, the PJM could be operated at higher temperatures for waste groups with high dissolved solids that suppress vapor pressure. The SO4 group with the highest vapor pressure suppression could be operated up to 153°F before reaching the same vapor pressure of water at 145°F. However, most groups would reach equivalent vapor pressure at 147 to 148°F. If any of these waste streams are diluted, the vapor pressure can exceed the vapor pressure of water at mass dilution ratios greater than 10, but the overall effect is less than 0.5%.

  8. Vapor generation methods for explosives detection research

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Ewing, Robert G.; Atkinson, David A.

    2012-12-01

    The generation of calibrated vapor samples of explosives compounds remains a challenge due to the low vapor pressures of the explosives, adsorption of explosives on container and tubing walls, and the requirement to manage (typically) multiple temperature zones as the vapor is generated, diluted, and delivered. Methods that have been described to generate vapors can be classified as continuous or pulsed flow vapor generators. Vapor sources for continuous flow generators are typically explosives compounds supported on a solid support, or compounds contained in a permeation or diffusion device. Sources are held at elevated isothermal temperatures. Similar sources can be used for pulsed vapor generators; however, pulsed systems may also use injection of solutions onto heated surfaces with generation of both solvent and explosives vapors, transient peaks from a gas chromatograph, or vapors generated by s programmed thermal desorption. This article reviews vapor generator approaches with emphasis on the method of generating the vapors and on practical aspects of vapor dilution and handling. In addition, a gas chromatographic system with two ovens that is configurable with up to four heating ropes is proposed that could serve as a single integrated platform for explosives vapor generation and device testing. Issues related to standards, calibration, and safety are also discussed.

  9. Microstructure of vapor deposited coatings on curved substrates

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G., E-mail: haydn@virginia.edu [Department of Materials Science and Engineering, University of Virginia, 395 McCormick Rd., P.O. Box 400745, Charlottesville, Virginia 22904 (United States)

    2015-09-15

    Thermal barrier coating systems consisting of a metallic bond coat and ceramic over layer are widely used to extend the life of gas turbine engine components. They are applied using either high-vacuum physical vapor deposition techniques in which vapor atoms rarely experience scattering collisions during propagation to a substrate, or by gas jet assisted (low-vacuum) vapor deposition techniques that utilize scattering from streamlines to enable non-line-of-sight deposition. Both approaches require substrate motion to coat a substrate of complex shape. Here, direct simulation Monte Carlo and kinetic Monte Carlo simulation methods are combined to simulate the deposition of a nickel coating over the concave and convex surfaces of a model airfoil, and the simulation results are compared with those from experimental depositions. The simulation method successfully predicted variations in coating thickness, columnar growth angle, and porosity during both stationary and substrate rotated deposition. It was then used to investigate a wide range of vapor deposition conditions spanning high-vacuum physical vapor deposition to low-vacuum gas jet assisted vapor deposition. The average coating thickness was found to increase initially with gas pressure reaching a maximum at a chamber pressure of 8–10 Pa, but the best coating thickness uniformity was achieved under high vacuum deposition conditions. However, high vacuum conditions increased the variation in the coatings pore volume fraction over the surface of the airfoil. The simulation approach was combined with an optimization algorithm and used to investigate novel deposition concepts to tailor the local coating thickness.

  10. Microstructure of vapor deposited coatings on curved substrates

    International Nuclear Information System (INIS)

    Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G.

    2015-01-01

    Thermal barrier coating systems consisting of a metallic bond coat and ceramic over layer are widely used to extend the life of gas turbine engine components. They are applied using either high-vacuum physical vapor deposition techniques in which vapor atoms rarely experience scattering collisions during propagation to a substrate, or by gas jet assisted (low-vacuum) vapor deposition techniques that utilize scattering from streamlines to enable non-line-of-sight deposition. Both approaches require substrate motion to coat a substrate of complex shape. Here, direct simulation Monte Carlo and kinetic Monte Carlo simulation methods are combined to simulate the deposition of a nickel coating over the concave and convex surfaces of a model airfoil, and the simulation results are compared with those from experimental depositions. The simulation method successfully predicted variations in coating thickness, columnar growth angle, and porosity during both stationary and substrate rotated deposition. It was then used to investigate a wide range of vapor deposition conditions spanning high-vacuum physical vapor deposition to low-vacuum gas jet assisted vapor deposition. The average coating thickness was found to increase initially with gas pressure reaching a maximum at a chamber pressure of 8–10 Pa, but the best coating thickness uniformity was achieved under high vacuum deposition conditions. However, high vacuum conditions increased the variation in the coatings pore volume fraction over the surface of the airfoil. The simulation approach was combined with an optimization algorithm and used to investigate novel deposition concepts to tailor the local coating thickness

  11. Vapor generating unit blowdown arrangement

    International Nuclear Information System (INIS)

    McDonald, B.N.

    1978-01-01

    A vapor generating unit having a U-shaped tube bundle is provided with an orificed downcomer shroud and a fluid flow distribution plate between the lower hot and cold leg regions to promote fluid entrained sediment deposition in proximity to an apertured blowdown pipe

  12. Kovacs-Like Memory Effect in Driven Granular Gases

    Science.gov (United States)

    Prados, A.; Trizac, E.

    2014-05-01

    While memory effects have been reported for dense enough disordered systems such as glasses, we show here by a combination of analytical and simulation techniques that they are also intrinsic to the dynamics of dilute granular gases. By means of a certain driving protocol, we prepare the gas in a state where the granular temperature T coincides with its long time limit. However, T does not subsequently remain constant but exhibits a nonmonotonic evolution before reaching its nonequilibrium steady value. The corresponding so-called Kovacs hump displays a normal behavior for weak dissipation (as observed in molecular systems) but is reversed under strong dissipation, where it, thus, becomes anomalous.

  13. Process of producing carbonaceous materials; reaction with hydrogen gases

    Energy Technology Data Exchange (ETDEWEB)

    1933-01-13

    A process is described for the production of valuable hydrocarbons by treating distillable carbonaceous materials together with hydrogen gases, under pressure and in contact with catalysts, the process consisting in adding to the original materials, first or during treatment, organic sulfonic acids together with metals from the fourth or eighth groups of the periodic system or a combination of these, or organic carbosilicic acids or inorganic acids containing oxides of sulfur or nitrogen or the anhydrides of these inorganic acids or variation of these compounds.

  14. Processes to remove acid forming gases from exhaust gases

    Science.gov (United States)

    Chang, S.G.

    1994-09-20

    The present invention relates to a process for reducing the concentration of NO in a gas, which process comprises: (A) contacting a gas sample containing NO with a gaseous oxidizing agent to oxidize the NO to NO[sub 2]; (B) contacting the gas sample of step (A) comprising NO[sub 2] with an aqueous reagent of bisulfite/sulfite and a compound selected from urea, sulfamic acid, hydrazinium ion, hydrazoic acid, nitroaniline, sulfanilamide, sulfanilic acid, mercaptopropanoic acid, mercaptosuccinic acid, cysteine or combinations thereof at between about 0 and 100 C at a pH of between about 1 and 7 for between about 0.01 and 60 sec; and (C) optionally contacting the reaction product of step (A) with conventional chemical reagents to reduce the concentrations of the organic products of the reaction in step (B) to environmentally acceptable levels. Urea or sulfamic acid are preferred, especially sulfamic acid, and step (C) is not necessary or performed. 16 figs.

  15. Calculation of thermodynamic properties of sodium and potassium vapors on the base of semiempirical state equation. Group integrals and virial coefficients

    International Nuclear Information System (INIS)

    Reva, T.D.; Semenov, A.M.

    1984-01-01

    Statistically significant estimations of the second, third and fourth group integrals of sodium and potassium vapors were obtained in the framework of the initial atom method on the basis of semiempirical equation of state derived by the authors. Possibility is duscussed of estimating dimer, trimer and tetramer concentrations from these data with account of unideality of vapors. High rate of convergence of density and pressure group expansion is demonstrated. Virial coefficients were calculated. It is shown that virial expansions of thermodynamic functions diverge at elevated densities of the gases under study. The estimations of senior virial coefficients of sodium and potassium vapors available in literature were proved to be faulty

  16. Graphene by one-step chemical vapor deposition from ferrocene vapors: Properties and electrochemical evaluation

    Science.gov (United States)

    Pilatos, George; Perdikaki, Anna V.; Sapalidis, Andreas; Pappas, George S.; Giannakopoulou, Tatiana; Tsoutsou, Dimitra; Xenogiannopoulou, Evangelia; Boukos, Nikos; Dimoulas, Athanasios; Trapalis, Christos; Kanellopoulos, Nick K.; Karanikolos, Georgios N.

    2016-02-01

    Growth of few-layer graphene using ferrocene as precursor by chemical vapor deposition is reported. The growth did not involve any additional carbon or catalyst source or external hydrocarbon gases. Parametric investigation was performed using different conditions, namely, varying growth temperature from 600 to1000 °C, and growth duration from 5 min to 3 h, as well as using fast quenching or gradual cooling after the thermal treatment, in order to examine the effect on the quality of the produced graphene. The growth took place on silicon wafers and resulted, under optimal conditions, in formation of graphene with 2-3 layers and high graphitic quality, as evidenced by Raman spectroscopy, with characteristic full width at half maximum of the 2D band of 49.46 cm-1, and I2D/IG and ID/IG intensity ratios of 1.15 and 0.26, respectively. Atomic force microscopy and X-ray photoelectron spectroscopy were employed to further evaluate graphene characteristics and enlighten growth mechanism. Electrochemical evaluation of the developed material was performed using cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge measurements.

  17. Noble gas studies in vapor-growth diamonds: Comparison with shock-produced diamonds and the origin of diamonds in ureilites

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Junichi; Fukunaga, Kazuya; Ito, Keisuke (Kobe Univ. (Japan))

    1991-07-01

    The authors synthesized vapor-trowth diamonds by two kinds of Chemical Vapor Deposition (CVD) using microwave (MWCVD) and hot filament (HFCVD) ionization of gases, and examined elemental abundances and isotopic compositions of the noble gases trapped in the diamonds. It is remarkable that strong differences existed in the noble gas concentrations in the two kinds of CVD diamonds: large amounts of noble gases were trapped in the MWCVD diamonds, but not in the HFCVD diamonds. The heavy noble gases (Ar to Xe) in the MWCVD diamonds were highly fractionated compared with those in the ambient atmosphere, and are in good agreement with the calculated fractionation patterns for plasma at an electron temperature of 7,000-9,000 K. These results strongly suggest that the trapping mechanism of noble gases in CVD diamonds is ion implantation during diamond growth. The degrees of fractionation of heavy noble gases were also in good agreement with those in ureilites. The vapor-growth hypothesis is discussed in comparison with the impact-shock hypothesis as a better model for the origin of diamonds in ureilites. The diamond (and graphite, amorphous carbon, too) may have been deposited on early condensates such as Re, Ir, W, etc. This model explains the chemical features of vein material in ureilites; the refractory siderophile elements are enriched in carbon and noble gases and low in normal siderophiles. The vapor-growth model is also compatible with the oxygen isotopic data of ureilites which suggests that nebular processes are primarily responsible for the composition of ureilites.

  18. Hanford soil partitioning and vapor extraction study

    International Nuclear Information System (INIS)

    Yonge, D.; Hossain, A.; Cameron, R.; Ford, H.; Storey, C.

    1996-07-01

    This report describes the testing and results of laboratory experiments conducted to assist the carbon tetrachloride soil vapor extraction project operating in the 200 West Area of the Hanford Site in Richland, Washington. Vapor-phase adsorption and desorption testing was performed using carbon tetrachloride and Hanford Site soils to estimate vapor-soil partitioning and reasonably achievable carbon tetrachloride soil concentrations during active vapor extractions efforts at the 200 West Area. (CCl 4 is used in Pu recovery from aqueous streams.)

  19. Vapor Pressure Data Analysis and Statistics

    Science.gov (United States)

    2016-12-01

    near 8, 2000, and 200, respectively. The A (or a) value is directly related to vapor pressure and will be greater for high vapor pressure materials...1, (10) where n is the number of data points, Yi is the natural logarithm of the i th experimental vapor pressure value, and Xi is the...VAPOR PRESSURE DATA ANALYSIS AND STATISTICS ECBC-TR-1422 Ann Brozena RESEARCH AND TECHNOLOGY DIRECTORATE

  20. Shale gases, a windfall for France?

    International Nuclear Information System (INIS)

    Tonnac, Alain de; Perves, Jean-Pierre

    2013-11-01

    After having recalled the definition and origin of shale gases, the different non conventional gases and their exploitation techniques (hydraulic fracturing and horizontal drilling) this report examines whether these gases are an opportunity for France. Some characteristics and data of the fossil and gas markets are presented and commented: world primary energy consumption, proved reserves of non conventional gases and their locations, European regions which may possess reserves of shale gases and coal-bed methane, origins of gas imports in France. The second part addresses shale gas deposits and their exploitation: discussion of the influence of the various rock parameters, evolution of production. The third part discusses the exploitation techniques and specific drilling tools. The issue of exploitation safety and security is addressed as well as the associated controversies: about the pollution of underground waters, about the fact that deep drillings result in pollution, about the risks associated with hydraulic fracturing and injections of chemical products, about the hold on ground and site degradation, about water consumption, about pollution due to gas pipeline leakage, about seismic risk, about noise drawbacks, about risks for health, about exploration and production authorization and license, and about air pollution and climate. The last part addresses the French situation and its future: status of the energy bill, recommendations made by a previous government, cancellation of authorizations, etc. Other information are provided in appendix about non conventional hydrocarbons, about shale gas exploitation in the USA, and about the Lacq gas

  1. Reconciling Gases With Glasses: Magma Degassing, Overturn and Mixing at Kilauea Volcano, Hawai`i

    Science.gov (United States)

    Edmonds, M.; Gerlach, T. M.

    2006-12-01

    Our understanding of the volatile budget at Kilauea Volcano is based on measurements of the abundance of volatile elements in volcanic glasses and gases. Observations of volcanic gases gave rise to a fundamental model describing volatile fractionation between the summit and rift zone during the current eruption [Gerlach and Graeber, 1985]. Other workers' analysis of glasses from the Puna Ridge, Kilauea Iki and Pu`u `O`o indicate that magma degassing, drain-back, mixing and assimilation are important processes at Kilauea Volcano. Volcanic gases have not illustrated these kinds of processes clearly in the past, owing to infrequent and poorly resolved data. New, detailed studies of volcanic gas emissions have refined our understanding of volatile degassing and magma budgets at Kilauea Volcano. Open Path Fourier Transform Infra-Red spectroscopy measurements carried out during 2004-2005 allow retrieval of the relative abundances of the major volatile species H2O, CO2 and SO2, which together make up >99 vol% of the magmatic vapor phase. The proportions of these gases vary over time and space and can be used to infer magma transport, ascent, degassing, overturn and mixing and gas segregation processes within the plumbing system of Kilauea Volcano. Gases from Pu`u `O`o in 2004-2005 display a range in composition. A trend relates molar C/S to the total H2O content of the gases over time and space; total H2O ranges from 60-98 mol %, while molar C/S ranges from 50. The range in volcanic gas composition over time and space is caused by magma degassing, overturn and mixing of partially degassed magma with fresh primary magma beneath Pu`u `O`o. Measurements of the mean rate of magma degassing (from SO2 emissions) and mean lava effusion rate (from geophysical measurements of lava tube flux) suggest that a larger volume (DRE) of magma is degassing than is being erupted, on average. This analysis suggests that magma storage in the Rift Zone might be important during eruptions as

  2. Defect analysis in low temperature atomic layer deposited Al{sub 2}O{sub 3} and physical vapor deposited SiO barrier films and combination of both to achieve high quality moisture barriers

    Energy Technology Data Exchange (ETDEWEB)

    Maindron, Tony, E-mail: tony.maindron@cea.fr; Jullien, Tony; André, Agathe [Université Grenoble-Alpes, CEA, LETI, MINATEC Campus, 17 rue des Martyrs, F-38054 Grenoble Cedex 9 (France)

    2016-05-15

    low defect growth rate of 0.032/cm{sup 2}/h (t > τ) have been measured. At the end of the storage test (2003 h), the defect density remains very low, i.e., only 50/cm{sup 2}. On the other hand, the device with the single PVD-deposited SiO barrier layer shows no significant lag time (τ ∼ 0), and the number of defects grows linearly from initial time with a high occurrence rate of 0.517/cm{sup 2}/h. This is coherent with the pinhole-full nature of fresh, PVD-deposited, SiO films. At intermediate times, a second regime shows a lower defect occurrence rate of 0.062/cm{sup 2}/h. At a longer time span (t > 1200 h), the SiO barrier begins to degrade, and a localized crystallization onto the oxide surface, giving rise to new defects (occurrence rate 0.461/cm{sup 2}/h), could be observed. At the end of the test (2003 h), single SiO films show a very high defect density of 600/cm{sup 2}. Interestingly, the SiO surface in the Al{sub 2}O{sub 3}/SiO device does not appeared crystallized at a high time span, suggesting that the crystallization observed on the SiO surface in the AlQ{sub 3}/SiO device rather originates into the AlQ{sub 3} layer, due to high humidity ingress on the organic layer through SiO pinholes. This has been confirmed by atomic force microscopy surface imaging of the AlQ{sub 3}/SiO surface showing a central hole in the crystallization zone with a 60 nm depth, deeper than SiO thickness (25 nm). Using the organic AlQ{sub 3} sensor, the different observations made in this work give a quantitative comparison of defects' occurrence and growth in ALD-deposited versus PVD-deposited oxide films, as well as in their combination PVD/ALD and ALD/PVD.

  3. Accounting for the Effect of Noncondensing Gases on Interphasic Heat and Mass Transfer in the Two-Fluid Model Used in the KORSAR Code

    Science.gov (United States)

    Yudov, Yu. V.

    2018-03-01

    A model is presented of the interphasic heat and mass transfer in the presence of noncondensable gases for the KORSAR/GP design code. This code was developed by FGUP NITI and the special design bureau OKB Gidropress. It was certified by Rostekhnadzor in 2009 for numerical substantiation of the safety of reactor installations with VVER reactors. The model is based on the assumption that there are three types of interphasic heat and mass transfer of the vapor component: vapor condensation or evaporation on the interphase under any thermodynamic conditions of the phases, pool boiling of the liquid superheated above the saturation temperature at the total pressure, and spontaneous condensation in the volume of gas phase supercooled below the saturation temperature at the vapor partial pressure. Condensation and evaporation on the interphase continuously occur in a two-phase flow and control the time response of the interphase heat and mass transfer. Boiling and spontaneous condensation take place only at the metastable condition of the phases and run at a quite high speed. The procedure used for calculating condensation and evaporation on the interphase accounts for the combined diffusion and thermal resistance of mass transfer in all regimes of the two-phase flow. The proposed approach accounts for, in a natural manner, a decrease in the rate of steam condensation (or generation) in the presence of noncondensing components in the gas phase due to a decrease (or increase) in the interphase temperature relative to the saturation temperature at the vapor partial pressure. The model of the interphase heat transfer also accounts for the processes of dissolution or release of noncondensing components in or from the liquid. The gas concentration at the interphase and on the saturation curve is calculated by the Henry law. The mass transfer coefficient in gas dissolution is based on the heat and mass transfer analogy. Results are presented of the verification of the

  4. Turbomolecular Pumps for Holding Gases in Open Containers

    Science.gov (United States)

    Keller, John W.; Lorenz, John E.

    2010-01-01

    Proposed special-purpose turbomolecular pumps denoted turbotraps would be designed, along with mating open containers, to prevent the escape of relatively slowly (thermal) moving gas molecules from the containers while allowing atoms moving at much greater speeds to pass through. In the original intended applications, the containers would be electron-attachment cells, and the contained gases would be vapors of alkali metal atoms moving at thermal speeds that would be of the order of a fraction of 300 meters per second. These cells would be parts of apparatuses used to measure fluxes of neutral atoms incident at kinetic energies in the approximate range of 10 eV to 10 keV (corresponding to typical speeds of the order of 40,000 m/s and higher). The incident energetic neutral atoms would pass through the cells, wherein charge-exchange reactions with the alkali metal atoms would convert the neutral atoms to negative ions, which, in turn, could then be analyzed by use of conventional charged-particle optics.

  5. Estimating enthalpy of vaporization from vapor pressure using Trouton's rule.

    Science.gov (United States)

    MacLeod, Matthew; Scheringer, Martin; Hungerbühler, Konrad

    2007-04-15

    The enthalpy of vaporization of liquids and subcooled liquids at 298 K (delta H(VAP)) is an important parameter in environmental fate assessments that consider spatial and temporal variability in environmental conditions. It has been shown that delta H(VAP)P for non-hydrogen-bonding substances can be estimated from vapor pressure at 298 K (P(L)) using an empirically derived linear relationship. Here, we demonstrate that the relationship between delta H(VAP)and PL is consistent with Trouton's rule and the ClausiusClapeyron equation under the assumption that delta H(VAP) is linearly dependent on temperature between 298 K and the boiling point temperature. Our interpretation based on Trouton's rule substantiates the empirical relationship between delta H(VAP) degree and P(L) degrees for non-hydrogen-bonding chemicals with subcooled liquid vapor pressures ranging over 15 orders of magnitude. We apply the relationship between delta H(VAP) degrees and P(L) degrees to evaluate data reported in literature reviews for several important classes of semivolatile environmental contaminants, including polycyclic aromatic hydrocarbons, chlorobenzenes, polychlorinated biphenyls and polychlorinated dibenzo-dioxins and -furans and illustrate the temperature dependence of results from a multimedia model presented as a partitioning map. The uncertainty associated with estimating delta H(VAP)degrees from P(L) degrees using this relationship is acceptable for most environmental fate modeling of non-hydrogen-bonding semivolatile organic chemicals.

  6. Density Fluctuations in Uniform Quantum Gases

    International Nuclear Information System (INIS)

    Bosse, J.; Pathak, K. N.; Singh, G. S.

    2011-01-01

    Analytical expressions are given for the static structure factor S(k) and the pair correlation function g(r) for uniform ideal Bose-Einstein and Fermi-Dirac gases for all temperatures. In the vicinity of Bose Einstein condensation (BEC) temperature, g(r) becomes long ranged and remains so in the condensed phase. In the dilute gas limit, g(r) of bosons and fermions do not coincide with Maxwell-Boltzmann gas but exhibit bunching and anti-bunching effect respectively. The width of these functions depends on the temperature and is scaled as √(inverse atomic mass). Our numerical results provide the precise quantitative values of suppression/increase (antibunching and bunching) of the density fluctuations at small distances in ideal quantum gases in qualitative agreement with the experimental observation for almost non-trapped dilute gases.

  7. Method of processing radioactive rare gase

    International Nuclear Information System (INIS)

    Tagusagawa, Atsushi; Tuda, Kazuaki.

    1988-01-01

    Purpose: To obtain a safety processing method without using mechanical pumps or pressure-proof containers and, accordingly, with no risk for the leakage of radioactive rare gas. Method: A container filled with zeolige is inserted with a cover being opened into an autoclave. Meanwhile, krypton-containing gases are supplied to an adsorption tower filled with adsorbents, cooled, adsorbed and then heated to desorb adsorbed krypton. The krypton-containing gases are introduced due to the pressure difference to the autoclave thereby causing krypton to adsorb at ambient temperature to zeolite. Then, the inside of the autoclave is heated to desorb krypton and adsorbed moistures from zeolite and the pressure is elevated. After sending the gases under pressure to the adsorption tower, the zeolite-filled container is taken out from the autoclave, tightly closed and then transferred to a predetermined site. (Takahashi, M.)

  8. Dark lump excitations in superfluid Fermi gases

    Science.gov (United States)

    Xu, Yan-Xia; Duan, Wen-Shan

    2012-11-01

    We study the linear and nonlinear properties of two-dimensional matter-wave pulses in disk-shaped superfluid Fermi gases. A Kadomtsev—Petviashvili I (KPI) solitary wave has been realized for superfluid Fermi gases in the limited cases of Bardeen—Cooper—Schrieffer (BCS) regime, Bose—Einstein condensate (BEC) regime, and unitarity regime. One-lump solution as well as one-line soliton solutions for the KPI equation are obtained, and two-line soliton solutions with the same amplitude are also studied in the limited cases. The dependence of the lump propagating velocity and the sound speed of two-dimensional superfluid Fermi gases on the interaction parameter are investigated for the limited cases of BEC and unitarity.

  9. Dark lump excitations in superfluid Fermi gases

    International Nuclear Information System (INIS)

    Xu Yan-Xia; Duan Wen-Shan

    2012-01-01

    We study the linear and nonlinear properties of two-dimensional matter-wave pulses in disk-shaped superfluid Fermi gases. A Kadomtsev—Petviashvili I (KPI) solitary wave has been realized for superfluid Fermi gases in the limited cases of Bardeen—Cooper—Schrieffer (BCS) regime, Bose—Einstein condensate (BEC) regime, and unitarity regime. One-lump solution as well as one-line soliton solutions for the KPI equation are obtained, and two-line soliton solutions with the same amplitude are also studied in the limited cases. The dependence of the lump propagating velocity and the sound speed of two-dimensional superfluid Fermi gases on the interaction parameter are investigated for the limited cases of BEC and unitarity

  10. Anesthetic gases and global warming: Potentials, prevention and future of anesthesia.

    Science.gov (United States)

    Gadani, Hina; Vyas, Arun

    2011-01-01

    Global warming refers to an average increase in the earth's temperature, which in turn causes changes in climate. A warmer earth may lead to changes in rainfall patterns, a rise in sea level, and a wide range of impacts on plants, wildlife, and humans. Greenhouse gases make the earth warmer by trapping energy inside the atmosphere. Greenhouse gases are any gas that absorbs infrared radiation in the atmosphere and include: water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), halogenated fluorocarbons (HCFCs), ozone (O3), perfluorinated carbons (PFCs), and hydrofluorocarbons (HFCs). Hazardous chemicals enter the air we breathe as a result of dozens of activities carried out during a typical day at a healthcare facility like processing lab samples, burning fossil fuels etc. We sometimes forget that anesthetic agents are also greenhouse gases (GHGs). Anesthetic agents used today are volatile halogenated ethers and the common carrier gas nitrous oxide known to be aggressive GHGs. With less than 5% of the total delivered halogenated anesthetic being metabolized by the patient, the vast majority of the anesthetic is routinely vented to the atmosphere through the operating room scavenging system. The global warming potential (GWP) of a halogenated anesthetic is up to 2,000 times greater than CO2. Global warming potentials are used to compare the strength of different GHGs to trap heat in the atmosphere relative to that of CO2. Here we discuss about the GWP of anesthetic gases, preventive measures to decrease the global warming effects of anesthetic gases and Xenon, a newer anesthetic gas for the future of anesthesia.

  11. Tank vapor sampling and analysis data package for tank 241-C-106 waste retrieval sluicing system process test phase III

    Energy Technology Data Exchange (ETDEWEB)

    LOCKREM, L.L.

    1999-08-13

    This data package presents sampling data and analytical results from the March 28, 1999, vapor sampling of Hanford Site single-shell tank 241-C-106 during active sluicing. Samples were obtained from the 296-C-006 ventilation system stack and ambient air at several locations. Characterization Project Operations (CPO) was responsible for the collection of all SUMMATM canister samples. The Special Analytical Support (SAS) vapor team was responsible for the collection of all triple sorbent trap (TST), sorbent tube train (STT), polyurethane foam (PUF), and particulate filter samples collected at the 296-C-006 stack. The SAS vapor team used the non-electrical vapor sampling (NEVS) system to collect samples of the air, gases, and vapors from the 296-C-006 stack. The SAS vapor team collected and analyzed these samples for Lockheed Martin Hanford Corporation (LMHC) and Tank Waste Remediation System (TWRS) in accordance with the sampling and analytical requirements specified in the Waste Retrieval Sluicing System Vapor Sampling and Analysis Plan (SAP) for Evaluation of Organic Emissions, Process Test Phase III, HNF-4212, Rev. 0-A, (LMHC, 1999). All samples were stored in a secured Radioactive Materials Area (RMA) until the samples were radiologically released and received by SAS for analysis. The Waste Sampling and Characterization Facility (WSCF) performed the radiological analyses. The samples were received on April 5, 1999.

  12. Use of zeolites for the removal of volatile sulfur compounds from industrial waste gases and from natural gases

    Energy Technology Data Exchange (ETDEWEB)

    Dudzik,; Z,; Bilska, M

    1974-12-01

    The use of zeolites for the removal of sulfur dioxide from industrial waste gases and for the removal of hydrogen sulfide and volatile mercaptans from the natural gas or synthetic gas manufactured from coal is discussed. The effectiveness and cost of zeolite methods are superior to that of other methods. The best sorption properties with respect to sulfur dioxide are observed in faujasites and erionites. The molecular sieve 13X (a sodium form of low-silicon faujasite) is the most effective sorbent of hydrogen sulfide, produced commercially on a large scale. This zeolite is also a very effective catalyst for simultaneous oxygenation of hydrogen sulfide. The reaction with oxygen can begin at temperatures as low as -80/sup 0/C. The effectiveness of zeolite reactors is enhanced by the presence of oxygen in the gas being purified, and is hindered by the presence of water or water vapor. The extraordinary catalytic activity of sodium faujasites is due to free donors, and sulfur and oxygen ion donors at their surface. A zeolite reactor is also economical.

  13. Gases and vacua handbook of vacuum physics

    CERN Document Server

    Beck, A H

    2013-01-01

    Handbook of Vacuum Physics, Volume 1: Gases and Vacua presents three major topics, which are the fourth to sixth parts of this volume. These topics are the remarks on units of physical quantities; kinetic theory of gases and gaseous flow; and theory of vacuum diffusion pumps. The first topic aims to present concisely the significance of units of physical quantities, catering the need and interest of those who take measurements and make calculations in different fields of vacuum sciences. The technique and applications of this particular topic are also provided. The second main topic focuses sp

  14. Measuring Viscosities of Gases at Atmospheric Pressure

    Science.gov (United States)

    Singh, Jag J.; Mall, Gerald H.; Hoshang, Chegini

    1987-01-01

    Variant of general capillary method for measuring viscosities of unknown gases based on use of thermal mass-flowmeter section for direct measurement of pressure drops. In technique, flowmeter serves dual role, providing data for determining volume flow rates and serving as well-characterized capillary-tube section for measurement of differential pressures across it. New method simple, sensitive, and adaptable for absolute or relative viscosity measurements of low-pressure gases. Suited for very complex hydrocarbon mixtures where limitations of classical theory and compositional errors make theoretical calculations less reliable.

  15. Itinerant Ferromagnetism in Ultracold Fermi Gases

    DEFF Research Database (Denmark)

    Heiselberg, Henning

    2012-01-01

    Itinerant ferromagnetism in cold Fermi gases with repulsive interactions is studied applying the Jastrow-Slater approximation generalized to finite polarization and temperature. For two components at zero temperature a second order transition is found at akF ≃ 0.90 compatible with QMC. Thermodyna......Itinerant ferromagnetism in cold Fermi gases with repulsive interactions is studied applying the Jastrow-Slater approximation generalized to finite polarization and temperature. For two components at zero temperature a second order transition is found at akF ≃ 0.90 compatible with QMC...

  16. Indoor air pollution caused by geothermal gases

    International Nuclear Information System (INIS)

    Durand, Michael

    2006-01-01

    This paper discusses the little-known but potentially serious indoor air quality problems that may occur where buildings are constructed on geothermal ground. The main problems are related to seepage of carbon dioxide, hydrogen sulphide, radon and other gases from soil cavities directly into indoor air through perforations in the structure. These gases present a health hazard, and hydrogen sulphide, which is particularly corrosive, may cause problems electrical and electronic systems. Counter-measures are not always effective, so developments in such areas should only be undertaken with a clear understanding of site-specific issues and their possible solutions. (author)

  17. Ultracold Dipolar Gases in Optical Lattices

    OpenAIRE

    Trefzger, C.; Menotti, C.; Capogrosso-Sansone, B.; Lewenstein, M.

    2011-01-01

    This tutorial is a theoretical work, in which we study the physics of ultra-cold dipolar bosonic gases in optical lattices. Such gases consist of bosonic atoms or molecules that interact via dipolar forces, and that are cooled below the quantum degeneracy temperature, typically in the nK range. When such a degenerate quantum gas is loaded into an optical lattice produced by standing waves of laser light, new kinds of physical phenomena occur. These systems realize then extended Hubbard-type m...

  18. Portable device for generation of ultra-pure water vapor feeds

    Science.gov (United States)

    Velin, P.; Stenman, U.; Skoglundh, M.; Carlsson, P.-A.

    2017-11-01

    A portable device for the generation of co-feeds of water vapor has been designed, constructed, and evaluated for flexible use as an add-on component to laboratory chemical reactors. The vapor is formed by catalytic oxidation of hydrogen, which benefits the formation of well-controlled minute concentrations of ultra-pure water. Analysis of the effluent stream by on-line mass spectrometry and Fourier transform infrared spectroscopy confirms that water vapor can be, with high precision, generated both rapidly and steadily over extended periods in the range of 100 ppm to 3 vol. % (limited by safety considerations) using a total flow of 100 to 1500 ml/min at normal temperature and pressure. Further, the device has been used complementary to a commercial water evaporator and mixing system to span water concentrations up to 12 vol. %. Finally, an operando diffuse reflective infrared Fourier transform spectroscopic measurement of palladium catalysed methane oxidation in the absence and presence of up to 1.0 vol. % water has been carried out to demonstrate the applicability of the device for co-feeding well-controlled low concentrations of water vapor to a common type of spectroscopic experiment. The possibilities of creating isotopically labeled water vapor as well as using tracer gases for dynamic experiments are discussed.

  19. Vapor deposition of tantalum and tantalum compounds

    International Nuclear Information System (INIS)

    Trkula, M.

    1996-01-01

    Tantalum, and many of its compounds, can be deposited as coatings with techniques ranging from pure, thermal chemical vapor deposition to pure physical vapor deposition. This review concentrates on chemical vapor deposition techniques. The paper takes a historical approach. The authors review classical, metal halide-based techniques and current techniques for tantalum chemical vapor deposition. The advantages and limitations of the techniques will be compared. The need for new lower temperature processes and hence new precursor chemicals will be examined and explained. In the last section, they add some speculation as to possible new, low-temperature precursors for tantalum chemical vapor deposition

  20. What Good is Raman Water Vapor Lidar?

    Science.gov (United States)

    Whitman, David

    2011-01-01

    Raman lidar has been used to quantify water vapor in the atmosphere for various scientific studies including mesoscale meteorology and satellite validation. Now the international networks of NDACC and GRUAN have interest in using Raman water vapor lidar for detecting trends in atmospheric water vapor concentrations. What are the data needs for addressing these very different measurement challenges. We will review briefly the scientific needs for water vapor accuracy for each of these three applications and attempt to translate that into performance specifications for Raman lidar in an effort to address the question in the title of "What good is Raman water vapor Iidar."

  1. High temperature vapors science and technology

    CERN Document Server

    Hastie, John

    2012-01-01

    High Temperature Vapors: Science and Technology focuses on the relationship of the basic science of high-temperature vapors to some areas of discernible practical importance in modern science and technology. The major high-temperature problem areas selected for discussion include chemical vapor transport and deposition; the vapor phase aspects of corrosion, combustion, and energy systems; and extraterrestrial high-temperature species. This book is comprised of seven chapters and begins with an introduction to the nature of the high-temperature vapor state, the scope and literature of high-temp

  2. Importance Profiles for Water Vapor

    Science.gov (United States)

    Mapes, Brian; Chandra, Arunchandra S.; Kuang, Zhiming; Zuidema, Paquita

    2017-11-01

    Motivated by the scientific desire to align observations with quantities of physical interest, we survey how scalar importance functions depend on vertically resolved water vapor. Definitions of importance begin from familiar examples of water mass I m and TOA clear-sky outgoing longwave flux I OLR, in order to establish notation and illustrate graphically how the sensitivity profile or "kernel" depends on whether specific humidity S, relative humidity R, or ln( R) are used as measures of vapor. Then, new results on the sensitivity of convective activity I con to vapor (with implied knock-on effects such as weather prediction skill) are presented. In radiative-convective equilibrium, organized (line-like) convection is much more sensitive to moisture than scattered isotropic convection, but it exists in a drier mean state. The lesson for natural convection may be that organized convection is less susceptible to dryness and can survive and propagate into regions unfavorable for disorganized convection. This counterintuitive interpretive conclusion, with respect to the narrow numerical result behind it, highlights the importance of clarity about what is held constant at what values in sensitivity or susceptibility kernels. Finally, the sensitivities of observable radiance signals I sig for passive remote sensing are considered. While the accuracy of R in the lower free troposphere is crucial for the physical importance scalars, this layer is unfortunately the most difficult to isolate with passive remote sensing: In high emissivity channels, water vapor signals come from too high in the atmosphere (for satellites) or too low (for surface radiometers), while low emissivity channels have poor altitude discrimination and (in the case of satellites) are contaminated by surface emissions. For these reasons, active ranging (LiDAR) is the preferred observing strategy.

  3. Vapor Pressure of Antimony Triiodide

    Science.gov (United States)

    2017-12-07

    unlimited. iii Contents List of Figures iv 1. Introduction 1 2. Vapor Pressure 1 3. Experiment 3 4. Discussion and Measurements 5 5...SbI3 as a function of temperature ......................... 6 Approved for public release; distribution is unlimited. 1 1. Introduction ...single-crystal thin films of n-type (Bi,Sb)2(Te,Se)3 materials presents new doping challenges because it is a nonequilibrium process. (Bi,Sb)2(Te,Se)3

  4. Sodium vapor charge exchange cell

    International Nuclear Information System (INIS)

    Hiddleston, H.R.; Fasolo, J.A.; Minette, D.C.; Chrien, R.E.; Frederick, J.A.

    1976-01-01

    An operational sequential charge-exchange ion source yielding a 50 MeV H - current of approximately 8 mA is planned for use with the Argonne 500 MeV booster synchrotron. We report on the progress for development of a sodium vapor charge-exchange cell as part of that planned effort. Design, fabrication, and operating results to date are presented and discussed. (author)

  5. Assessment of water vapor content from MIVIS TIR data

    Directory of Open Access Journals (Sweden)

    V. Tramutoli

    2006-06-01

    Full Text Available The main objective of land remotely sensed images is to derive biological, chemical and physical parameters by inverting sample sets of spectral data. For the above aim hyperspectral scanners on airborne platform are a powerful remote sensing instrument for both research and environmental applications because of their spectral resolution and the high operability of the platform. Fine spectral information by MIVIS (airborne hyperspectral scanner operating in 102 channels ranging from VIS to TIR allows researchers to characterize atmospheric parameters and their effects on measured data which produce undesirable features on surface spectral signatures. These effects can be estimated (and remotely sensed radiances corrected if atmospheric spectral transmittance is known at each image pixel. Usually ground-based punctual observations (atmospheric sounding balloons, sun photometers, etc. are used to estimate the main physical parameters (like water vapor and temperature profiles which permit us to estimate atmospheric spectral transmittance by using suitable radiative transfer model and a specific (often too strong assumption which enable atmospheric properties measured only in very few points to be extended to the whole image. Several atmospheric gases produce observable absorption features, but only water vapor strongly varies in time and space. In this work the authors customize a self-sufficient «split-window technique» to derive (at each image pixel atmospheric total columnar water vapor content (TWVC using only MIVIS data collected by the fourth MIVIS spectrometer (Thermal Infrared band. MIVIS radiances have been simulated by means of MODTRAN4 radiative transfer code and the coefficients of linear regression to estimate TWVC from «split-windows» MIVIS radiances, based on 450 atmospheric water vapor profiles obtained by radiosonde data provided by NOAANESDIS. The method has been applied to produce maps describing the spatial variability of

  6. Development of Natural Gas Fired Combined Cycle Plant for Tri-Generation of Power, Cooling and Clean Water Using Waste Heat Recovery: Techno-Economic Analysis

    Directory of Open Access Journals (Sweden)

    Gowtham Mohan

    2014-10-01

    Full Text Available Tri-generation is one of the most efficient ways for maximizing the utilization of available energy. Utilization of waste heat (flue gases liberated by the Al-Hamra gas turbine power plant is analyzed in this research work for simultaneous production of: (a electricity by combining steam rankine cycle using heat recovery steam generator (HRSG; (b clean water by air gap membrane distillation (AGMD plant; and (c cooling by single stage vapor absorption chiller (VAC. The flue gases liberated from the gas turbine power cycle is the prime source of energy for the tri-generation system. The heat recovered from condenser of steam cycle and excess heat available at the flue gases are utilized to drive cooling and desalination cycles which are optimized based on the cooling energy demands of the villas. Economic and environmental benefits of the tri-generation system in terms of cost savings and reduction in carbon emissions were analyzed. Energy efficiency of about 82%–85% is achieved by the tri-generation system compared to 50%–52% for combined cycles. Normalized carbon dioxide emission per MW·h is reduced by 51.5% by implementation of waste heat recovery tri-generation system. The tri-generation system has a payback period of 1.38 years with cumulative net present value of $66 million over the project life time.

  7. Low concentration volatile organic pollutants removal in combined adsorber-desorber-catalytic reactor system

    Directory of Open Access Journals (Sweden)

    Arsenijević Zorana

    2008-01-01

    Full Text Available The removal of volatile organic compounds (VOCs from numerous emission sources is of crucial importance due to more rigorous demands on air quality. Different technologies can be used to treat the VOCs from effluent gases: absorption, physical adsorption, open flame combustion, thermal and catalytic incineration. Their appropriateness for the specific process depends on several factors such as efficiency, energy consumption, secondary pollution, capital investments etc. The distinctive features of the catalytic combustion are high efficiency and selectivity toward be­nign products, low energy consumption and absence of secondary polluti­on. The supported noble catalysts are widely used for catalytic incineration due to their low ignition temperatures and high thermal and chemical stability. In our combined system adsorption and desorption are applied in the spouted bed with draft tube (SBDT unit. The annular zone, loaded with sorbent, was divided in adsorption and desorption section. Draft tube enabled sorbent recirculation between sections. Combustion of desorbed gases to CO2 and water vapor are realized in additive catalytic reactor. This integrated device provided low concentrations VOCs removal with reduced energy consumption. Experiments were conducted on a pilot unit of 220 m3/h nominal capacity. The sorbent was activated carbon, type K81/B - Trayal Corporation, Krusevac. A sphere shaped commercial Pt/Al2O3 catalyst with "egg-shell" macro-distribution was used for the investigation of xylene deep oxidation. Within this paper the investigations of removal of xylene vapors, a typical pollutant in production of liquid pesticides, in combined adsorber/desorber/catalytic reactor system is presented.

  8. Fate of Gases generated from Nuclear Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasulu, M.; Francis, A. J. [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of); Francis, A. J. [Brookhaven National Laboratory, New York (United States)

    2013-05-15

    The backfill materials such as cement, bentonite or crushed rock are used as engineered barriers against groundwater infiltration and radionuclide transport. Gas generation from radioactive wastes is attributed to radiolysis, corrosion of metals, and degradation of organic materials. Corrosion of steel drums and biodegradation of organic materials in L/ILW can generate gas which causes pressure build up and has the potential to compromise the integrity of waste containers and release the radionuclides and other contaminants into the environment. Performance assessment therefore requires a detailed understanding of the source and fate of gas generation and transport within the disposal system. Here we review the sources and fate of various type of gases generated from nuclear wastes and repositories. Studies on modeling of the fate and transport of repository gases primarily deal with hydrogen and CO{sub 2}. Although hydrogen and carbon dioxide are the major gases of concern, microbial transformations of these gases in the subterranean environments could be significant. Metabolism of hydrogen along with the carbon dioxide results in the formation of methane, low molecular weight organic compounds and cell biomass and thus could affect the total inventory in a repository environment. Modeling studies should take into consideration of both the gas generation and consumption processes over the long-term.

  9. Electron-Atom Collisions in Gases

    Science.gov (United States)

    Kraftmakher, Yaakov

    2013-01-01

    Electron-atom collisions in gases are an aspect of atomic physics. Three experiments in this field employing a thyratron are described: (i) the Ramsauer-Townsend effect, (ii) the excitation and ionization potentials of xenon and (iii) the ion-electron recombination after interrupting the electric discharge.

  10. Acid dew point measurement in flue gases

    Energy Technology Data Exchange (ETDEWEB)

    Struschka, M.; Baumbach, G.

    1986-06-01

    The operation of modern boiler plants requires the continuous measurement of the acid dew point in flue gases. An existing measuring instrument was modified in such a way that it can determine acid dew points reliably, reproduceably and continuously. The authors present the mechanisms of the dew point formation, the dew point measuring principle, the modification and the operational results.

  11. Properties and Bibliography of GaSe

    Science.gov (United States)

    1994-02-01

    Musaev, A. E. Bakhyshev, N. M. Gasanly and L. G. Musaeva . (1975). "Anisotropy of the optical constants of GaS and GaSe near the absorption edge." Sov...Phys. Semiconductors. 9 94-95 Russian ref.: Fiz. Tekh. Poluprovodn. 9 142-145 (January 1975). Akhundov, G. A., L. G. Musaeva and M. D. Khomutova

  12. Mitigation of greenhouse gases from agriculture

    DEFF Research Database (Denmark)

    Schils, R.L.M.; Ellis, J. L.; de Klein, C. A. M.

    2013-01-01

    Models are widely used to simulate the emission of greenhouse gases (GHG). They help to identify knowledge gaps, estimate total emissions for inventories, develop mitigation options and policies, raise awareness and encourage adoption. These models vary in scale, scope and methodological approach...

  13. Toxicity of pyrolysis gases from polyether sulfone

    Science.gov (United States)

    Hilado, C. J.; Olcomendy, E. M.

    1979-01-01

    A sample of polyether sulfone was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Animal response times were relatively short at pyrolysis temperatures of 600 to 800 C, with death occurring within 6 min. The principal toxicant appeared to be a compound other than carbon monoxide.

  14. Anaesthetic gases: environmental impact and alternatives ...

    African Journals Online (AJOL)

    Anaesthetic gases: environmental impact and alternatives. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... to be small when compared to gaseous emissions from industrial and agricultural sources, the actual percentage contribution to climate change is small. ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  15. Cold quantum gases with resonant interactions

    NARCIS (Netherlands)

    Marcelis, B.

    2008-01-01

    We study ultracold gases of alkali-metal atoms in the quantum degenerate regime. The interatomic interactions in these type of systems can be tuned using resonances induced by magnetic or electric fields. The tunability of the interactions, together with the possibility of confining the atoms with

  16. Teacher's Guide for Balloons and Gases.

    Science.gov (United States)

    Griffith, Joe H.; And Others

    This guide was developed to provide children with an opportunity to prepare and collect several common gases and to discover and work with some of their properties. The guide is divided into five major sections: (1) introduction, (2) materials, (3) activities, (4) balloons aloft, and (5) an appendix. The introduction provides information…

  17. Prediction of friction coefficients for gases

    Science.gov (United States)

    Taylor, M. F.

    1969-01-01

    Empirical relations are used for correlating laminar and turbulent friction coefficients for gases, with large variations in the physical properties, flowing through smooth tubes. These relations have been used to correlate friction coefficients for hydrogen, helium, nitrogen, carbon dioxide and air.

  18. Plant for removing radioactive rare gases

    International Nuclear Information System (INIS)

    An, Buzai; Kanazawa, Toshio

    1977-01-01

    The outline of the pilot plant to remove and recover radioactive rare gases generated from nuclear power plants, reprocessing installations for nuclear fuel, nuclear research installations, etc. is described below. Among the studies of various processes such as liquefaction and distillation, absorption into solvents, active carbon adsorption, diaphragm method, etc., the liquefaction and distillation process by rectification at low temperature has been positively developed. It is in the stage of practical application for removing rare gases in waste gases from reprocessing and nuclear power plants. This is the process with high safety and excellent rare gas removing capability. Further research and development have been also made for selective adsorption and desorption method at low temperature which is very efficient as there is no release of long life nuclides such as Krypton-85. Rare gases recovered by the above mentioned removal systems must be stored safely for a long time as their half lives are long and specific radioactivities are high. The study has been made continuously on the storage methods including adsorption in cylinders and remotely automatically sealing storing system. (Kobatake, H.)

  19. Ab initio calculation of the interaction potentials of helium, neon, and methane as well as theoretical studies on their thermophysical properties and those of water vapor

    International Nuclear Information System (INIS)

    Hellmann, Robert

    2009-01-01

    Thermophysical properties of the pure gases helium, neon, methane and water vapor were calculated for low densities over wide temperature ranges. Statistical thermodynamics was used for the determination of the pressure virial coefficients. The kinetic theory of gases was utilized for the calculation of the transport and relaxation properties. So far kinetic theory was limited to linear molecules and has now been extended to molecules of arbitrary geometry to enable calculations on methane and water vapor. The interaction potentials, which are needed for all computations, were determined for helium, neon and methane from the supermolecular approach using quantum chemical ab initio methods. For water the interaction potentials were taken from the literature. The calculated values of the thermophysical properties for the four gases show very good agreement with the best experimental data. At very low and very high temperatures the theoretical values are more accurate than experimental data. (orig.)

  20. Cryogenic system for collecting noble gases from boiling water reactor off-gas

    International Nuclear Information System (INIS)

    Schmauch, G.E.

    1973-01-01

    In boiling water reactors, noncondensible gases are expelled from the main condenser. This off-gas stream is composed largely of radiolytic hydrogen and oxygen, air in-leakage, and traces of fission product krypton and xenon. In the Air Products' treatment system, the stoichiometric hydrogen and oxygen are reacted to form water in a catalytic recombiner. The design of the catalytic recombiner is an extension of industrial gas technology developed for purification of argon and helium. The off-gas after the recombiner is processed by cryogenic air-separation technology. The gas is compressed, passed into a reversing heat exchanger where water vapor and carbon dioxide are frozen out, further cooled, and expanded into a distillation column where refrigeration is provided by addition of liquid nitrogen. More than 99.99 percent of the krypton and essentially 100 percent of the xenon entering the column are accumulated in the column bottoms. Every three to six months, the noble-gas concentrate accumulated in the column bottom is removed as liquid, vaporized, diluted with steam, mixed with hydrogen in slight excess of oxygen content, and fed to a small recombiner where all the oxygen reacts to form water. The resulting gas stream, containing from 20 to 40 percent noble gases, is compressed into small storage cylinders for indefinite retention or for decay of all fission gases except krypton-85, followed by subsequent release under controlled conditions and favorable meteorology. This treatment system is based on proven technology that is practiced throughout the industrial gas industry. Only the presence of radioactive materials in the process stream and the application in a nuclear power plant environment are new. Adaptations to meet these new conditions can be made without sacrificing performance, reliability, or safety

  1. High Temperature Corrosion of Silicon Carbide and Silicon Nitride in Water Vapor

    Science.gov (United States)

    Opila, E. J.; Robinson, Raymond C.; Cuy, Michael D.; Gray, Hugh R. (Technical Monitor)

    2002-01-01

    Silicon carbide (SiC) and silicon nitride (Si3N4) are proposed for applications in high temperature combustion environments containing water vapor. Both SiC and Si3N4 react with water vapor to form a silica (SiO2) scale. It is therefore important to understand the durability of SiC, Si3N4 and SiO2 in water vapor. Thermogravimetric analyses, furnace exposures and burner rig results were obtained for these materials in water vapor at temperatures between 1100 and 1450 C and water vapor partial pressures ranging from 0.1 to 3.1 atm. First, the oxidation of SiC and Si3N4 in water vapor is considered. The parabolic kinetic rate law, rate dependence on water vapor partial pressure, and oxidation mechanism are discussed. Second, the volatilization of silica to form Si(OH)4(g) is examined. Mass spectrometric results, the linear kinetic rate law and a volatilization model based on diffusion through a gas boundary layer are discussed. Finally, the combined oxidation and volatilization reactions, which occur when SiC or Si3N4 are exposed in a water vapor-containing environment, are presented. Both experimental evidence and a model for the paralinear kinetic rate law are shown for these simultaneous oxidation and volatilization reactions.

  2. The Effect of High Temperature Annealing on the Grain Characteristics of a Thin Chemical Vapor Deposition Silicon Carbide Layer.

    Energy Technology Data Exchange (ETDEWEB)

    Isabella J van Rooyen; Philippus M van Rooyen; Mary Lou Dunzik-Gougar

    2013-08-01

    The unique combination of thermo-mechanical and physiochemical properties of silicon carbide (SiC) provides interest and opportunity for its use in nuclear applications. One of the applications of SiC is as a very thin layer in the TRi-ISOtropic (TRISO) coated fuel particles for high temperature gas reactors (HTGRs). This SiC layer, produced by chemical vapor deposition (CVD), is designed to withstand the pressures of fission and transmutation product gases in a high temperature, radiation environment. Various researchers have demonstrated that macroscopic properties can be affected by changes in the distribution of grain boundary plane orientations and misorientations [1 - 3]. Additionally, various researchers have attributed the release behavior of Ag through the SiC layer as a grain boundary diffusion phenomenon [4 - 6]; further highlighting the importance of understanding the actual grain characteristics of the SiC layer. Both historic HTGR fission product release studies and recent experiments at Idaho National Laboratory (INL) [7] have shown that the release of Ag-110m is strongly temperature dependent. Although the maximum normal operating fuel temperature of a HTGR design is in the range of 1000-1250°C, the temperature may reach 1600°C under postulated accident conditions. The aim of this specific study is therefore to determine the magnitude of temperature dependence on SiC grain characteristics, expanding upon initial studies by Van Rooyen et al, [8; 9].

  3. Tunable Rare Earth fcu-MOF Platform: Access to Adsorption Kinetics Driven Gas/Vapor Separations via Pore Size Contraction

    KAUST Repository

    Xue, Dongxu; Belmabkhout, Youssef; Shekhah, Osama; Jiang, Hao; Adil, Karim; Cairns, Amy J; Eddaoudi, Mohamed

    2015-01-01

    Reticular chemistry approach was successfully employed to deliberately construct new rare-earth (RE, i.e. Eu3+, Tb3+ and Y3+) fcu metal‒organic frameworks (MOFs) with restricted window apertures. Controlled and selective access to the resultant contracted fcu-MOF pores permits the achievement of the requisite sorbate cut-off ideal for selective adsorption kinetics separation and/or molecular sieving of gases and vapors. Predetermined reaction conditions that permitted the formation in-situ of the 12-connected RE hexanuclear molecular building block (MBB) and the establishment of the RE-fcu-MOF plat-form, especially in the presence of 2-fluorobenzoic acid (2-FBA) as a modulator and a structure directing agent, were used to synthesize isostructural RE-1,4-NDC-fcu-MOFs based on a relatively bulkier 2-connected bridging ligand, namely 1,4-naphthalenedicarboxylate (1,4-NDC). The subsequent RE-1,4-NDC-fcu-MOF structural features, contracted windows/pores and high concentration of open metal sites combined with exceptional hydrothermal and chemical stabilities, yielded nota-ble gas/solvent separation properties, driven mostly by adsorption kinetics as exemplified in this work for n-butane/methane, butanol/methanol and butanol/water pair systems.

  4. Tunable Rare Earth fcu-MOF Platform: Access to Adsorption Kinetics Driven Gas/Vapor Separations via Pore Size Contraction

    KAUST Repository

    Xue, Dongxu

    2015-03-31

    Reticular chemistry approach was successfully employed to deliberately construct new rare-earth (RE, i.e. Eu3+, Tb3+ and Y3+) fcu metal‒organic frameworks (MOFs) with restricted window apertures. Controlled and selective access to the resultant contracted fcu-MOF pores permits the achievement of the requisite sorbate cut-off ideal for selective adsorption kinetics separation and/or molecular sieving of gases and vapors. Predetermined reaction conditions that permitted the formation in-situ of the 12-connected RE hexanuclear molecular building block (MBB) and the establishment of the RE-fcu-MOF plat-form, especially in the presence of 2-fluorobenzoic acid (2-FBA) as a modulator and a structure directing agent, were used to synthesize isostructural RE-1,4-NDC-fcu-MOFs based on a relatively bulkier 2-connected bridging ligand, namely 1,4-naphthalenedicarboxylate (1,4-NDC). The subsequent RE-1,4-NDC-fcu-MOF structural features, contracted windows/pores and high concentration of open metal sites combined with exceptional hydrothermal and chemical stabilities, yielded nota-ble gas/solvent separation properties, driven mostly by adsorption kinetics as exemplified in this work for n-butane/methane, butanol/methanol and butanol/water pair systems.

  5. Tunable Rare Earth fcu-MOF Platform: Access to Adsorption Kinetics Driven Gas/Vapor Separations via Pore Size Contraction.

    Science.gov (United States)

    Xue, Dong-Xu; Belmabkhout, Youssef; Shekhah, Osama; Jiang, Hao; Adil, Karim; Cairns, Amy J; Eddaoudi, Mohamed

    2015-04-22

    Reticular chemistry approach was successfully employed to deliberately construct new rare-earth (RE, i.e., Eu(3+), Tb(3+), and Y(3+)) fcu metal-organic frameworks (MOFs) with restricted window apertures. Controlled and selective access to the resultant contracted fcu-MOF pores permits the achievement of the requisite sorbate cutoff, ideal for selective adsorption kinetics based separation and/or molecular sieving of gases and vapors. Predetermined reaction conditions that permitted the formation in situ of the 12-connected RE hexanuclear molecular building block (MBB) and the establishment of the first RE-fcu-MOF platform, especially in the presence of 2-fluorobenzoic acid (2-FBA) as a modulator and a structure directing agent, were used to synthesize isostructural RE-1,4-NDC-fcu-MOFs based on a relatively bulkier 2-connected bridging ligand, namely 1,4-naphthalenedicarboxylate (1,4-NDC). The subsequent RE-1,4-NDC-fcu-MOF structural features, contracted windows/pores and high concentration of open metal sites combined with exceptional hydrothermal and chemical stabilities, yielded notable gas/solvent separation properties, driven mostly by adsorption kinetics as exemplified in this work for n-butane/methane, butanol/methanol, and butanol/water pair systems.

  6. Prediction of oxy-coal combustion through an optimized weighted sum of gray gases model

    International Nuclear Information System (INIS)

    Kangwanpongpan, Tanin; Corrêa da Silva, Rodrigo; Krautz, Hans Joachim

    2012-01-01

    Oxy-fuel combustion is considered as one of promising options for carbon dioxide capture in future coal power plants. Currently models available in CFD codes fail to predict accurately the radiative heat transfer in oxy-fuel cases due to higher pressure of carbon dioxide and water vapor. This paper concerns numerical investigation applying three band formulations aiming an accurate prediction of radiative properties. The radiative heat transfer is calculated by discrete ordinate method coupled with a weighted sum of gray gases model. The first case relates to the domain-based approach using air-fired parameters. In the last two cases, the optimized parameters of 3 and 4 gray gases fitted to oxy-fired conditions are implemented through a non-gray gases approach. Results applying these set of parameters are evaluated through a comparison with experimental data. Discrepancies between the predicted and measured velocity and O 2 concentration are found mainly close to the burner due to shortcomings of the turbulence model and inaccurate thermochemical closure. The gas flame temperatures are better predicted by the optimized parameters for oxy-fuel conditions, which are considerably lower than the values calculated by the air-fired parameters. Similar trends are observed when the radiative heat fluxes at the lateral wall are compared.

  7. Purification of burned gases of domestic wastes; Moderna purificacion de gases quemados de las basuras domesticas

    Energy Technology Data Exchange (ETDEWEB)

    Gottschalk, J.; Buttman, P.; Johansson, T.

    1997-09-01

    The author presents the technology to reduce the emission from the burned gases purification of domestic wastes combustion. The technology was demonstrated in Hobec, Denmark, and developed in Germany. (Author)

  8. The Origin and Time Dependence of the Amount and Composition of Non-Constituent Gases Present in Crystal Growth Systems

    Science.gov (United States)

    Palosz, Witold

    1998-01-01

    Presence of different, non-constituent gases may be a critical factor in crystal growth systems. In Physical Vapor Transport processes the cras(es) can be used intentionally (to prevent excessively high, unstable growth conditions), or can evolve unintentionally during the course of the process (which may lead to undesired reduction in the -rowth rate). In melt growth, particularly under low gravity conditions (reduced hydrostatic pressure) the gas present in the system may contribute to formation of voids in the growing crystals and even to a separation of the crystal and the liquid phase [1]. On the other hand, some amount of gas may facilitate 'contactless' crystal growth particularly under reduced gravity conditions [2 - 6]. Different non-constituent gases may be present in growth ampoules, and their amount and composition may change during the crystallization process. Some gases can appear even in empty ampoules sealed originally under high vacuum: they may diffuse in from the outside, and/or desorb from the ampoule walls. Residual gases can also be generated by the source materials: even very high purity commercial elements and compounds may contain trace amounts of impurities, particularly oxides. The oxides may have low volatilities themselves but their reaction with other species, particularly carbon and hydrogen, may produce volatile compounds like water or carbon oxides. The non-constituent gases, either added initially to the system or evolved during the material processing, may diffuse out of the ampoule during the course of the experiment. Gases present outside (e.g. as a protective atmosphere or thermal conductor) may diffuse into the ampoule. In either case the growth conditions and the quality of the crystals may be affected. The problem is of a particular importance in sealed systems where the amount of the gases cannot be directly controlled. Therefore a reasonable knowledge and understanding of the origin, composition, magnitude, and change with

  9. Overview of chemical vapor infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Besmann, T.M.; Stinton, D.P.; Lowden, R.A.

    1993-06-01

    Chemical vapor infiltration (CVI) is developing into a commercially important method for the fabrication of continuous filament ceramic composites. Current efforts are focused on the development of an improved understanding of the various processes in CVI and its modeling. New approaches to CVI are being explored, including pressure pulse infiltration and microwave heating. Material development is also proceeding with emphasis on improving the oxidation resistance of the interfacial layer between the fiber and matrix. This paper briefly reviews these subjects, indicating the current state of the science and technology.

  10. Efficiency of utilization of heat of moisture from exhaust gases of heat HRSG of CCGT

    OpenAIRE

    Galashov Nikolay; Tsibulskiy Svyatoslav; Mel’nikov Denis; Kiselev Alexandr; Gabdullina Al’bina

    2017-01-01

    The paper discusses the technology of utilizing the heat of exhaust gas moisture from heat recovery steam gases (HRSG) of combined-cycle gas turbine (CCGT). Particular attention focused on the influence of the excess air factor on the trapping of the moisture of the exhaust gases, as in the HRSG of the CCGT its value varies over a wider range than in the steam boilers of the TPP. For the research, has been developed a mathematical model that allows to determine the volumes of combustion produ...

  11. A Lithium Vapor Box Divertor Similarity Experiment

    Science.gov (United States)

    Cohen, Robert A.; Emdee, Eric D.; Goldston, Robert J.; Jaworski, Michael A.; Schwartz, Jacob A.

    2017-10-01

    A lithium vapor box divertor offers an alternate means of managing the extreme power density of divertor plasmas by leveraging gaseous lithium to volumetrically extract power. The vapor box divertor is a baffled slot with liquid lithium coated walls held at temperatures which increase toward the divertor floor. The resulting vapor pressure differential drives gaseous lithium from hotter chambers into cooler ones, where the lithium condenses and returns. A similarity experiment was devised to investigate the advantages offered by a vapor box divertor design. We discuss the design, construction, and early findings of the vapor box divertor experiment including vapor can construction, power transfer calculations, joint integrity tests, and thermocouple data logging. Heat redistribution of an incident plasma-based heat flux from a typical linear plasma device is also presented. This work supported by DOE Contract No. DE-AC02-09CH11466 and The Princeton Environmental Institute.

  12. Thermogravimetric measurements of liquid vapor pressure

    International Nuclear Information System (INIS)

    Rong Yunhong; Gregson, Christopher M.; Parker, Alan

    2012-01-01

    Highlights: ► Rapid determination of vapor pressure by TGA. ► Demonstration of limitations of currently available approaches in literature. ► New model for vapor pressure assessment of small size samples in TGA. ► New model accounts for vapor diffusion and sample geometry and measures vapor pressure normally within 10%. - Abstract: A method was developed using thermo-gravimetric analysis (TGA) to determine the vapor pressure of volatile liquids. This is achieved by measuring the rate of evaporation (mass loss) of a pure liquid contained within a cylindrical pan. The influence of factors like sample geometry and vapor diffusion on evaporation rate are discussed. The measurement can be performed across a wide range of temperature yielding reasonable results up to 10 kPa. This approach may be useful as a rapid and automatable method for measuring the volatility of flavor and fragrance raw materials.

  13. Scanning Raman lidar for tropospheric water vapor profiling and GPS path delay correction

    Science.gov (United States)

    Tarniewicz, Jerome; Bock, Olivier; Pelon, Jacques R.; Thom, Christian

    2002-01-01

    The design of a ground based and transportable combined Raman elastic-backscatter lidar for the remote sensing of lower tropospheric water vapor and nitrogen concentration is described. This lidar is intended to be used for an external calibration of the wet path delay of GPS signals. A description of the method used to derive water vapor and nitrogen profiles in the lower troposphere is given. The instrument has been tested during the ESCOMPTE campaign in June 2001 and first measurements are presented.

  14. EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

    Science.gov (United States)

    The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

  15. 75 FR 57669 - Mandatory Reporting of Greenhouse Gases

    Science.gov (United States)

    2010-09-22

    ... Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This action amends the Final Mandatory Reporting of Greenhouse Gases Rule to require reporters... Numbers GHG greenhouse gas GHGRP Greenhouse Gas Reporting Program HCFC hydrochlorofluorocarbon HFC...

  16. Geodesics in thermodynamic state spaces of quantum gases

    International Nuclear Information System (INIS)

    Oshima, H.; Obata, T.; Hara, H.

    2002-01-01

    The geodesics for ideal quantum gases are numerically studied. We show that 30 ideal quantum state is connected to an ideal classical state by geodesics and that the bundle of geodesics for Bose gases have a tendency of convergence

  17. Nonequilibrium steady states of ideal bosonic and fermionic quantum gases.

    Science.gov (United States)

    Vorberg, Daniel; Wustmann, Waltraut; Schomerus, Henning; Ketzmerick, Roland; Eckardt, André

    2015-12-01

    We investigate nonequilibrium steady states of driven-dissipative ideal quantum gases of both bosons and fermions. We focus on systems of sharp particle number that are driven out of equilibrium either by the coupling to several heat baths of different temperature or by time-periodic driving in combination with the coupling to a heat bath. Within the framework of (Floquet-)Born-Markov theory, several analytical and numerical methods are described in detail. This includes a mean-field theory in terms of occupation numbers, an augmented mean-field theory taking into account also nontrivial two-particle correlations, and quantum-jump-type Monte Carlo simulations. For the case of the ideal Fermi gas, these methods are applied to simple lattice models and the possibility of achieving exotic states via bath engineering is pointed out. The largest part of this work is devoted to bosonic quantum gases and the phenomenon of Bose selection, a nonequilibrium generalization of Bose condensation, where multiple single-particle states are selected to acquire a large occupation [Phys. Rev. Lett. 111, 240405 (2013)]. In this context, among others, we provide a theory for transitions where the set of selected states changes, describe an efficient algorithm for finding the set of selected states, investigate beyond-mean-field effects, and identify the dominant mechanisms for heat transport in the Bose-selected state.

  18. Impacts of acid gases on mercury oxidation across SCR catalyst

    International Nuclear Information System (INIS)

    Zhuang, Ye; Laumb, Jason; Liggett, Richard; Holmes, Mike; Pavlish, John

    2007-01-01

    A series of bench-scale experiments were completed to evaluate acid gases of HCl, SO 2 , and SO 3 on mercury oxidation across a commercial selective catalytic reduction (SCR) catalyst. The SCR catalyst was placed in a simulated flue gas stream containing O 2 , CO 2 , H 2 O, NO, NO 2 , and NH 3 , and N 2 . HCl, SO 2 , and SO 3 were added to the gas stream either separately or in combination to investigate their interactions with mercury over the SCR catalyst. The compositions of the simulated flue gas represent a medium-sulfur and low- to medium-chlorine coal that could represent either bituminous or subbituminous. The experimental data indicated that 5-50 ppm HCl in flue gas enhanced mercury oxidation within the SCR catalyst, possibly because of the reactive chlorine species formed through catalytic reactions. An addition of 5 ppm HCl in the simulated flue gas resulted in mercury oxidation of 45% across the SCR compared to only 4% mercury oxidation when 1 ppm HCl is in the flue gas. As HCl concentration increased to 50 ppm, 63% of Hg oxidation was reached. SO 2 and SO 3 showed a mitigating effect on mercury chlorination to some degree, depending on the concentrations of SO 2 and SO 3 , by competing against HCl for SCR adsorption sites. High levels of acid gases of HCl (50 ppm), SO 2 (2000 ppm), and SO 3 (50 ppm) in the flue gas deteriorate mercury adsorption on the SCR catalyst. (author)

  19. Nonequilibrium steady states of ideal bosonic and fermionic quantum gases

    Science.gov (United States)

    Vorberg, Daniel; Wustmann, Waltraut; Schomerus, Henning; Ketzmerick, Roland; Eckardt, André

    2015-12-01

    We investigate nonequilibrium steady states of driven-dissipative ideal quantum gases of both bosons and fermions. We focus on systems of sharp particle number that are driven out of equilibrium either by the coupling to several heat baths of different temperature or by time-periodic driving in combination with the coupling to a heat bath. Within the framework of (Floquet-)Born-Markov theory, several analytical and numerical methods are described in detail. This includes a mean-field theory in terms of occupation numbers, an augmented mean-field theory taking into account also nontrivial two-particle correlations, and quantum-jump-type Monte Carlo simulations. For the case of the ideal Fermi gas, these methods are applied to simple lattice models and the possibility of achieving exotic states via bath engineering is pointed out. The largest part of this work is devoted to bosonic quantum gases and the phenomenon of Bose selection, a nonequilibrium generalization of Bose condensation, where multiple single-particle states are selected to acquire a large occupation [Phys. Rev. Lett. 111, 240405 (2013), 10.1103/PhysRevLett.111.240405]. In this context, among others, we provide a theory for transitions where the set of selected states changes, describe an efficient algorithm for finding the set of selected states, investigate beyond-mean-field effects, and identify the dominant mechanisms for heat transport in the Bose-selected state.

  20. Non-equilibrium dynamics of one-dimensional Bose gases

    International Nuclear Information System (INIS)

    Langen, T.

    2013-01-01

    Understanding the non-equilibrium dynamics of isolated quantum many-body systems is an open problem on vastly different energy, length, and time scales. Examples range from the dynamics of the early universe and heavy-ion collisions to the subtle coherence and transport properties in condensed matter physics. However, realizations of such quantum many-body systems, which are both well isolated from the environment and accessible to experimental study are scarce. This thesis presents a series of experiments with ultracold one-dimensional Bose gases. These gases combine a nearly perfect isolation from the environment with many well-established methods to manipulate and probe their quantum states. This makes them an ideal model system to explore the physics of quantum many body systems out of equilibrium. In the experiments, a well-defined non-equilibrium state is created by splitting a single one-dimensional gas coherently into two parts. The relaxation of this state is probed using matter-wave interferometry. The Observations reveal the emergence of a prethermalized steady state which differs strongly from thermal equilibrium. Such thermal-like states had previously been predicted for a large variety of systems, but never been observed directly. Studying the relaxation process in further detail shows that the thermal correlations of the prethermalized state emerge locally in their final form and propagate through the system in a light-cone-like evolution. This provides first experimental evidence for the local relaxation conjecture, which links relaxation processes in quantum many-body systems to the propagation of correlations. Furthermore, engineering the initial state of the evolution demonstrates that the prethermalized state is described by a generalized Gibbs ensemble, an observation which substantiates the importance of this ensemble as an extension of standard statistical mechanics. Finally, an experiment is presented, where pairs of gases with an atom

  1. Ion vapor deposition and its application

    International Nuclear Information System (INIS)

    Bollinger, H.; Schulze, D.; Wilberg, R.

    1981-01-01

    Proceeding from the fundamentals of ion vapor deposition the characteristic properties of ion-plated coatings are briefly discussed. Examples are presented of successful applications of ion-plated coatings such as coatings with special electrical and dielectric properties, coatings for corrosion prevention, and coatings for improving the surface properties. It is concluded that ion vapor deposition is an advantageous procedure in addition to vapor deposition. (author)

  2. [Atomic Vapor Laser Isotope Separation (AVLIS) program

    International Nuclear Information System (INIS)

    1992-01-01

    This report summarizes work performed for the Atomic Vapor Laser Isotope Separation (AVLIS) program from January through July, 1992. Each of the tasks assigned during this period is described, and results are presented. Section I details work on sensitivity matrices for the UDS relay telescope. These matrices show which combination of mirror motions may be performed in order to effect certain changes in beam parameters. In Section II, an analysis is given of transmission through a clipping aperture on the launch telescope deformable mirror. Observed large transmission losses could not be simulated in the analysis. An EXCEL spreadsheet program designed for in situ analysis of UDS optical systems is described in Section III. This spreadsheet permits analysis of changes in beam first-order characteristics due to changes in any optical system parameter, simple optimization to predict mirror motions needed to effect a combination of changes in beam parameters, and plotting of a variety of first-order data. Optical systems may be assembled directly from OSSD data. A CODE V nonsequential model of the UDS optical system is described in Section IV. This uses OSSD data to build the UDS model; mirror coordinates may thus be verified. Section V summarizes observations of relay telescope performance. Possible procedures which allow more accurate assessment of relay telescope performance are given

  3. Effect of cooling the recirculated exhaust gases on diesel engine emissions

    International Nuclear Information System (INIS)

    Abu-Hamdeh, Nidal H.

    2003-01-01

    Although combustion is essential in most energy generation processes, it is one of the major causes of air pollution. Spiral fin exhaust pipes were designed to study the effect of cooling the recirculated exhaust gases (EGR) of Diesel engines on the chemical composition of the exhaust gases and the reduction in the percentages of pollutant emissions. The gases examined in this study were oxides of nitrogen (NO x ), carbon dioxide (CO 2 ) and carbon monoxide (CO). In addition, O 2 concentration in the exhaust was measured. The two designs adopted in this study were exhaust pipes with solid and hollow fins around them. The first type uses air flow around the fins to cool the exhaust gases. The second type consists of hollow fins around the exhaust pipe to allow cooling water to flow in the hollow passage. Different combinations and arrangements of the solid and hollow fins exhaust pipes were used. It was found that decreasing the temperature of the EGR resulted in reductions in the oxides of nitrogen (NO x ) and carbon dioxide (CO 2 ) but increased the carbon monoxide (CO) in the exhaust gases. In addition, the oxygen (O 2 ) concentration in the exhaust was decreased. As a general trend, the percentages of reduction in the NO x gas concentrations were lower than the percentages of increase in the CO emissions as a result of cooling the EGR of a Diesel engine by a heat exchanger. Using water as a cooling medium decreased the exhaust gases temperature and the amount of pollutants more than did air as a cooling medium. In a separate series of tests, increasing the cooled EGR ratios decreased the exhaust NO x but increased the particulate matter concentrations in the exhaust gases

  4. Effect of cooling the recirculated exhaust gases on diesel engine emissions

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Hamdeh, Nidal H. [Jordan Univ. of Science and Technology, Irbid (Jordan)

    2003-11-01

    Although combustion is essential in most energy generation processes, it is one of the major causes of air pollution. Spiral fin exhaust pipes were designed to study the effect of cooling the recirculated exhaust gases (EGR) of Diesel engines on the chemical composition of the exhaust gases and the reduction in the percentages of pollutant emissions. The gases examined in this study were oxides of nitrogen (NO{sub x}), carbon dioxide (CO{sub 2}) and carbon monoxide (CO). In addition, O{sub 2} concentration in the exhaust was measured. The two designs adopted in this study were exhaust pipes with solid and hollow fins around them. The first type uses air flow around the fins to cool the exhaust gases. The second type consists of hollow fins around the exhaust pipe to allow cooling water to flow in the hollow passage. Different combinations and arrangements of the solid and hollow fins exhaust pipes were used. It was found that decreasing the temperature of the EGR resulted in reductions in the oxides of nitrogen (NO{sub x}) and carbon dioxide (CO{sub 2}) but increased the carbon monoxide (CO) in the exhaust gases. In addition, the oxygen (O{sub 2}) concentration in the exhaust was decreased. As a general trend, the percentages of reduction in the NO{sub x} gas concentrations were lower than the percentages of increase in the CO emissions as a result of cooling the EGR of a Diesel engine by a heat exchanger. Using water as a cooling medium decreased the exhaust gases temperature and the amount of pollutants more than did air as a cooling medium. In a separate series of tests, increasing the cooled EGR ratios decreased the exhaust NO{sub x} but increased the particulate matter concentrations in the exhaust gases. (Author)

  5. Radiolytic generation of gases in reactors

    International Nuclear Information System (INIS)

    Ramshesh, V.; Venkateswarlu, K.S.

    1988-01-01

    Water or heavy water is used in different circuits in a reactor. Their most common use is as a moderator and/or as a coolant. Light water is used at other places such as in end shield, calandria vault etc., In the process they are exposed to intense ionizing radiation and undergo radiolytic degradation. The molecular produts of radiolysis are hydrogen, hydrogen peroxide and oxygen. As is commonly known if hydrogen is formed beyond a certain level, in the presence of oxygen it may lead to combustion or even explosion. Thus one should comprehend the basic principles of radiolysis and see whether the concentration of these gases under various conditions can be worked out. This report attempts to analyse in depth the radiolytic generation of gases in reactor systems. (author). 3 tabs

  6. Simulation of diffusion in concentrated lattice gases

    International Nuclear Information System (INIS)

    Kehr, K.W.

    1986-01-01

    Recently the diffusion of particles in lattice gases was studied extensively by theoretical methods and numerical simulations. This paper reviews work on collective and, in particular, on tracer diffusion. The diffusion of tagged particles is characterized by a correlation factor whose behavior as a function of concentration is now well understood. Also the detailed kinetics of the tracer transitions was investigated. A special case is the one-dimensional lattice gas where the tracer diffusion coefficient vanishes. An interesting extension is the case of tagged atoms with a different transition rate. This model allows to study various physical situations, including impurity diffusion, percolation, and diffusion in partially blocked lattices. Finally some recent work on diffusion in lattice gases under the influence of a drift field will be reported. (author)

  7. Functional renormalization and ultracold quantum gases

    International Nuclear Information System (INIS)

    Floerchinger, Stefan

    2010-01-01

    Modern techniques from quantum field theory are applied in this work to the description of ultracold quantum gases. This leads to a unified description of many phenomena including superfluidity for bosons and fermions, classical and quantum phase transitions, different dimensions, thermodynamic properties and few-body phenomena as bound state formation or the Efimov effect. The non-perturbative treatment with renormalization group flow equations can account for all known limiting cases by solving one single equation. It improves previous results quantitatively and brings qualitatively new insights. As an example, new quantum phase transitions are found for fermions with three spin states. Ultracold atomic gases can be seen as an interesting model for features of high energy physics and for condensed matter theory. The research reported in this thesis helps to solve the difficult complexity problem in modern theoretical physics. (orig.)

  8. Properties of quantum self-gravitating gases

    International Nuclear Information System (INIS)

    Rumyantseva, E.N.

    1981-01-01

    Ways of development of the quantum field theory in the general relativity theory are under consideration. A direction, where consideration of quantum fields in strong nonstatic gravitational fields leads to such effects as particle production, is found out. Authors managed to explain properties of quantum self-gravitating gases on the base of an expansion the fugacity in power series for bose- and fermi gases. Expressions for fluctuations in statistical models of the Fridmann universe are presented. The spectrum density of relict neutrinos in Fridmann models is calculated. A characteristic low boundary of the neutrino energy spectrum constitutes 1 MeV. A number of neutrinos with such energies practically is equal to zero. A great number of neutrinos has energies 0 . It is precisely these neurinos, which are responsible for the closed state of the universe according to the built up model

  9. Detecting Friedel oscillations in ultracold Fermi gases

    Science.gov (United States)

    Riechers, Keno; Hueck, Klaus; Luick, Niclas; Lompe, Thomas; Moritz, Henning

    2017-09-01

    Investigating Friedel oscillations in ultracold gases would complement the studies performed on solid state samples with scanning-tunneling microscopes. In atomic quantum gases interactions and external potentials can be tuned freely and the inherently slower dynamics allow to access non-equilibrium dynamics following a potential or interaction quench. Here, we examine how Friedel oscillations can be observed in current ultracold gas experiments under realistic conditions. To this aim we numerically calculate the amplitude of the Friedel oscillations which are induced by a potential barrier in a 1D Fermi gas and compare it to the expected atomic and photonic shot noise in a density measurement. We find that to detect Friedel oscillations the signal from several thousand one-dimensional systems has to be averaged. However, as up to 100 parallel one-dimensional systems can be prepared in a single run with present experiments, averaging over about 100 images is sufficient.

  10. Two-Dimensional Homogeneous Fermi Gases

    Science.gov (United States)

    Hueck, Klaus; Luick, Niclas; Sobirey, Lennart; Siegl, Jonas; Lompe, Thomas; Moritz, Henning

    2018-02-01

    We report on the experimental realization of homogeneous two-dimensional (2D) Fermi gases trapped in a box potential. In contrast to harmonically trapped gases, these homogeneous 2D systems are ideally suited to probe local as well as nonlocal properties of strongly interacting many-body systems. As a first benchmark experiment, we use a local probe to measure the density of a noninteracting 2D Fermi gas as a function of the chemical potential and find excellent agreement with the corresponding equation of state. We then perform matter wave focusing to extract the momentum distribution of the system and directly observe Pauli blocking in a near unity occupation of momentum states. Finally, we measure the momentum distribution of an interacting homogeneous 2D gas in the crossover between attractively interacting fermions and bosonic dimers.

  11. Comparing greenhouse gases for policy purposes

    International Nuclear Information System (INIS)

    Schmalensee, R.

    1993-01-01

    In order to derive optimal policies for greenhouse gas emissions control, the discounted marginal damages of emissions from different gases must be compared. The greenhouse warming potential (GWP) index, which is most often used to compare greenhouse gases, is not based on such a damage comparison. This essay presents assumptions under which ratios of gas-specific discounted marginal damages reduce to ratios of discounted marginal contributions to radiative forcing, where the discount rate is the difference between the discount rate relevant to climate-related damages and the rate of growth of marginal climate-related damages over time. If there are important gas-specific costs or benefits not tied to radiative forcing, however, such as direct effects of carbon dioxide on plant growth, there is in general no shortcut around explicit comparison of discounted net marginal damages. 16 refs

  12. Oxygen partial pressure sensor for gases

    International Nuclear Information System (INIS)

    Barbero, J.A.; Azcona, M.A.; Orce, A.

    1997-01-01

    Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10 -6 -1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs

  13. Oxygen partial pressure sensor for gases

    Energy Technology Data Exchange (ETDEWEB)

    Barbero, J.A.; Azcona, M.A.; Orce, A. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    1997-10-01

    Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10{sup -6}-1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs.

  14. Method for enhancing microbial utilization rates of gases using perfluorocarbons

    Science.gov (United States)

    Turick, C.E.

    1997-06-10

    A method of enhancing the bacterial reduction of industrial gases using perfluorocarbons (PFCs) is disclosed. Because perfluorocarbons (PFCs) allow for a much greater solubility of gases than water does, PFCs have the potential to deliver gases in higher concentrations to microorganisms when used as an additive to microbial growth media thereby increasing the rate of the industrial gas conversion to economically viable chemicals and gases. 3 figs.

  15. Monofilament Vaporization Propulsion (MVP) System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Monofilament Vaporization Propulsion (MVP) is a new propulsion technology targeted at secondary payload applications. It does not compromise on performance while...

  16. Oxidation of trichloroethylene, toluene, and ethanol vapors by a partially saturated permeable reactive barrier

    Science.gov (United States)

    Mahmoodlu, Mojtaba G.; Hassanizadeh, S. Majid; Hartog, Niels; Raoof, Amir

    2014-08-01

    The mitigation of volatile organic compound (VOC) vapors in the unsaturated zone largely relies on the active removal of vapor by ventilation. In this study we considered an alternative method involving the use of solid potassium permanganate to create a horizontal permeable reactive barrier for oxidizing VOC vapors. Column experiments were carried out to investigate the oxidation of trichloroethylene (TCE), toluene, and ethanol vapors using a partially saturated mixture of potassium permanganate and sand grains. Results showed a significant removal of VOC vapors due to the oxidation. We found that water saturation has a major effect on the removal capacity of the permeable reactive layer. We observed a high removal efficiency and reactivity of potassium permanganate for all target compounds at the highest water saturation (Sw = 0.6). A change in pH within the reactive layer reduced oxidation rate of VOCs. The use of carbonate minerals increased the reactivity of potassium permanganate during the oxidation of TCE vapor by buffering the pH. Reactive transport of VOC vapors diffusing through the permeable reactive layer was modeled, including the pH effect on the oxidation rates. The model accurately described the observed breakthrough curve of TCE and toluene vapors in the headspace of the column. However, miscibility of ethanol in water in combination with produced water during oxidation made the modeling results less accurate for ethanol. A linear relationship was found between total oxidized mass of VOC vapors per unit volume of permeable reactive layer and initial water saturation. This behavior indicates that pH changes control the overall reactivity and longevity of the permeable reactive layer during oxidation of VOCs. The results suggest that field application of a horizontal permeable reactive barrier can be a viable technology against upward migration of VOC vapors through the unsaturated zone.

  17. Vapor pressures and thermophysical properties of selected hexenols and recommended vapor pressure for hexan-1-ol

    Czech Academy of Sciences Publication Activity Database

    Štejfa, V.; Fulem, Michal; Růžička, K.; Matějka, P.

    2015-01-01

    Roč. 402, Sep (2015), 18-29 ISSN 0378-3812 Institutional support: RVO:68378271 Keywords : alcohols * vapor pressure * heat capacity * ideal - gas thermodynamic properties * vaporization enthalpy Subject RIV: BJ - Thermodynamics Impact factor: 1.846, year: 2015

  18. Role of buffer gases in optoacoustic spectroscopy

    International Nuclear Information System (INIS)

    Thomas III, L.J.; Kelly, M.J.; Amer, N.M.

    1978-01-01

    The dependence of an acoustically resonant optoacoustic signal on the molecular weight and thermodynamic and transport properpties of the buffer gas is reported. Our results show that careful selection of such gases can significantly increase the sensitivity and flexibility of optoacoustic spectroscopy. We also demonstrate that such thermodynamic quantities as γ (equivalentC/sub p//C/sub v/) and sound velocity can now be measured readily and accurately. Other potential applications are suggested

  19. Splitting of inviscid fluxes for real gases

    Science.gov (United States)

    Liou, Meng-Sing; Van Leer, Bram; Shuen, Jian-Shun

    1990-01-01

    Flux-vector and flux-difference splittings for the inviscid terms of the compressible flow equations are derived under the assumption of a general equation of state for a real gas in equilibrium. No necessary assumptions, approximations for auxiliary quantities are introduced. The formulas derived include several particular cases known for ideal gases and readily apply to curvilinear coordinates. Applications of the formulas in a TVD algorithm to one-dimensional shock-tube and nozzle problems show their quality and robustness.

  20. The Osher scheme for real gases

    Science.gov (United States)

    Suresh, Ambady; Liou, Meng-Sing

    1990-01-01

    An extension of Osher's approximate Riemann solver to include gases with an arbitrary equation of state is presented. By a judicious choice of thermodynamic variables, the Riemann invariats are reduced to quadratures which are then approximated numerically. The extension is rigorous and does not involve any further assumptions or approximations over the ideal gas case. Numerical results are presented to demonstrate the feasibility and accuracy of the proposed method.

  1. Effect of Greenhouse Gases Dissolved in Seawater.

    Science.gov (United States)

    Matsunaga, Shigeki

    2015-12-30

    A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region.

  2. The effects of spin in gases

    International Nuclear Information System (INIS)

    Laloee, F.; Freed, J.H.

    1988-01-01

    Low-density gases, in which atoms are separated by large distances, have long provided an enjoyable playground for physicists. One might suppose the pleasure of the playground would by now have been exhausted by the very simplicity of low-density gases. Recent work by a number of investigators including the author shows that this is not the case low-density gases continue to serve up a rich variety of phenomena as well as counterintuitive surprises. In particular, the macroscopic properties of a gas composed of individual hydrogen or helium atoms can under special circumstances by changed dramatically by quantum-mechanical effects. According to quantum theory, the nucleus of an atom behaves in a way similar to a rotating top, which has angular momentum about its axis of rotation; that is, the nucleus has spin, known more precisely as spin angular momentum. If the atoms of a gas are spin-polarized, so that their nuclei all have their spins pointing in the same direction, the viscosity of the gas can be changed enormously and so can its ability to conduct heat. Quantum-mechanical correlations among the nuclei called spin waves, which up to now had been observed only in certain liquids and solids such as magnets, can also arise. The changes are large enough for one to say the quantum-mechanical effects have caused the gas to take on entirely new properties. In a certain sense it is amazing to think that polarizing the nuclear spins can have any effect on the macroscopic properties of the gas, since the nuclear spins are son weakly coupled to the outside world. Yet the observations are in full agreement with with theory. Moreover, because spin-polarized gases are still fairly simple systems, they can be understood in terms fundamental principles, something that is still not possible to do in the case of liquids and solids

  3. How to wrap up radioactive gases

    Energy Technology Data Exchange (ETDEWEB)

    Keller, C

    1982-04-01

    Operating nuclear power stations produces not only solid waste. Not so well known - but they should by no means be ignored - are the radioactive gases released during fission which somehow have to be retained and 'packaged'. Gas cylinders, such as those used for oxygen or compressed air, are unsuitable for this purpose. Ingenious chemical tricks have been thought up to press the gas - especially crypton-85 - into plastic material in which it remains captured right down to its molecular structure.

  4. Glass Membrane For Controlled Diffusion Of Gases

    Science.gov (United States)

    Shelby, James E.; Kenyon, Brian E.

    2001-05-15

    A glass structure for controlled permeability of gases includes a glass vessel. The glass vessel has walls and a hollow center for receiving a gas. The glass vessel contains a metal oxide dopant formed with at least one metal selected from the group consisting of transition metals and rare earth metals for controlling diffusion of the gas through the walls of the glass vessel. The vessel releases the gas through its walls upon exposure to a radiation source.

  5. Numerical investigation of a novel burner to combust anode exhaust gases of SOFC stacks

    Directory of Open Access Journals (Sweden)

    Pianko-Oprych Paulina

    2017-09-01

    Full Text Available The aim of the present study was a numerical investigation of the efficiency of the combustion process of a novel concept burner under different operating conditions. The design of the burner was a part of the development process of a complete SOFC based system and a challenging combination of technical requirements to be fulfilled. A Computational Fluid Dynamics model of a non-premixed burner was used to simulate combustion of exhaust gases from the anode region of Solid Oxide Fuel Cell stacks. The species concentrations of the exhaust gases were compared with experimental data and a satisfactory agreement of the conversion of hydrocarbons was obtained. This validates the numerical methodology and also proves applicability of the developed approach that quantitatively characterized the interaction between the exhaust gases and burner geometry for proper combustion modelling. Thus, the proposed CFD approach can be safely used for further numerical optimisation of the burner design.

  6. Agreements on emission of greenhouse gases

    International Nuclear Information System (INIS)

    Aulstad, Johan Greger

    2001-01-01

    Agreements on emission of greenhouse gases is one of the instruments used by Norwegian authorities to meet their obligations with respect to the Climate Convention and the Kyoto Protocol. This book discusses the legal issues raised by these agreements. A main topic is how the industrial emissions conform to the Pollution Act. Does the Pollution Act apply to these emissions? What is the impact of the sanction rules in this act on the emissions? The book also deals with the following general questions that arise in connection with the application of public authority: (1) Can the administration grant concessions and permits in the form of agreements? (2) What commitments can be imposed on a private party by the administration by agreement? (3) Should the procedures set down in the Pollution Act and in the Public Administration Act be followed fully when the pollution authorities make agreements? Is the opportunity of the administration to reverse more restricted when they make agreements than when they make one-sided decisions? Although this discussion primarily deals with the emission of greenhouse gases, the reasoning and conclusions are relevant in many other types of agreements in which the public administration is one of the parties. The agreement that regulates the emissions of greenhouse gases from the Norwegian aluminium industry is described in a special section. The book also gives a brief account of how agreements are used in the Danish climate policy

  7. Diffusion coefficients gases, dissolved in fluid of NPPs circulation contours

    International Nuclear Information System (INIS)

    Piontkovskij, A.I.

    2000-01-01

    In article is brought analysis of diverse gases diffusion coefficients computation methods, dissolved in liquid. On the basis of this analysis and treatment of being equalizations for concrete gases and certain parameters offers universal diffusion coefficients determination dependence for diverse gases in wide range of parameters, circulation contours typical for work NPP

  8. 30 CFR 75.322 - Harmful quantities of noxious gases.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Harmful quantities of noxious gases. 75.322... quantities of noxious gases. Concentrations of noxious or poisonous gases, other than carbon dioxide, shall... Governmental Industrial Hygienists in “Threshold Limit Values for Substance in Workroom Air” (1972). Detectors...

  9. 76 FR 73885 - Mandatory Reporting of Greenhouse Gases

    Science.gov (United States)

    2011-11-29

    ... Mandatory Reporting of Greenhouse Gases; Final Rule #0;#0;Federal Register / Vol. 76, No. 229 / Tuesday... 98 [EPA-HQ-OAR-2011-0147; FRL-9493-9] RIN 2060-AQ85 Mandatory Reporting of Greenhouse Gases AGENCY... the Mandatory Reporting of Greenhouse Gases Rule to correct certain technical and editorial errors...

  10. 76 FR 47391 - Mandatory Reporting of Greenhouse Gases

    Science.gov (United States)

    2011-08-04

    ... Mandatory Reporting of Greenhouse Gases; Proposed Rule #0;#0;Federal Register / Vol. 76, No. 150 / Thursday...-HQ-OAR-2011-0147; FRL-9443-1] RIN 2060-AQ85 Mandatory Reporting of Greenhouse Gases AGENCY... provisions in the Mandatory Reporting of Greenhouse Gases Rule to correct certain technical and editorial...

  11. Thermodynamics of Quantum Gases for the Entire Range of Temperature

    Science.gov (United States)

    Biswas, Shyamal; Jana, Debnarayan

    2012-01-01

    We have analytically explored the thermodynamics of free Bose and Fermi gases for the entire range of temperature, and have extended the same for harmonically trapped cases. We have obtained approximate chemical potentials for the quantum gases in closed forms of temperature so that the thermodynamic properties of the quantum gases become…

  12. Headspace vapor characterization of Hanford waste Tank 241-C-201: Results from samples collected on 06/19/96

    International Nuclear Information System (INIS)

    Thomas, B.L.; Evans, J.C.; Pool, K.H.; Olsen, K.B.; Fruchter, J.S.; Silvers, K.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-C-201 (Tank C-201) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, on sample volumes provided by WHC. A summary, of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in a table. Detailed descriptions of the analytical results appear in the appendices

  13. Development of an instrument to measure the concentration of noncondensable gases in geothermal discharges. Final report, October 1, 1978-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Blair, C.K.; Harrison, R.F.

    1980-01-01

    Reported herein is a summary of a project to design, construct, and test a device which will continuously measure the vapor phase concentration of noncendensable gases in saturated steam/water geothermal discharges. Descriptions of the design, operating procedures, measurement accuracy, and limitations of the device are included. Also presented are results of laboratory testing and of field demonstration of the instrument. Recommendations for further refinement and development of the apparatus are discussed.

  14. Polarization (ellipsometric) measurements of liquid condensate deposition and evaporation rates and dew points in flowing salt/ash-containing combustion gases

    Science.gov (United States)

    Seshadri, K.; Rosner, D. E.

    1985-01-01

    An application of an optical polarization technique in a combustion environment is demonstrated by following, in real-time, growth rates of boric oxide condensate on heated platinum ribbons exposed to seeded propane-air combustion gases. The results obtained agree with the results of earlier interference measurements and also with theoretical chemical vapor deposition predictions. In comparison with the interference method, the polarization technique places less stringent requirements on surface quality, which may justify the added optical components needed for such measurements.

  15. Process for the preparation of fiber-reinforced ceramic composites by chemical vapor deposition

    Science.gov (United States)

    Lackey, Jr., Walter J.; Caputo, Anthony J.

    1986-01-01

    A chemical vapor deposition (CVD) process for preparing fiber-reinforced ceramic composites. A specially designed apparatus provides a steep thermal gradient across the thickness of a fibrous preform. A flow of gaseous ceramic matrix material is directed into the fibrous preform at the cold surface. The deposition of the matrix occurs progressively from the hot surface of the fibrous preform toward the cold surface. Such deposition prevents the surface of the fibrous preform from becoming plugged. As a result thereof, the flow of reactant matrix gases into the uninfiltrated (undeposited) portion of the fibrous preform occurs throughout the deposition process. The progressive and continuous deposition of ceramic matrix within the fibrous preform provides for a significant reduction in process time over known chemical vapor deposition processes.

  16. The impact of vaporized nanoemulsions on ultrasound-mediated ablation.

    Science.gov (United States)

    Zhang, Peng; Kopechek, Jonathan A; Porter, Tyrone M

    2013-01-01

    The clinical feasibility of using high-intensity focused ultrasound (HIFU) for ablation of solid tumors is limited by the high acoustic pressures and long treatment times required. The presence of microbubbles during sonication can increase the absorption of acoustic energy and accelerate heating. However, formation of microbubbles within the tumor tissue remains a challenge. Phase-shift nanoemulsions (PSNE) have been developed as a means for producing microbubbles within tumors. PSNE are emulsions of submicron-sized, lipid-coated, and liquid perfluorocarbon droplets that can be vaporized into microbubbles using short (5 MPa) acoustic pulses. In this study, the impact of vaporized phase-shift nanoemulsions on the time and acoustic power required for HIFU-mediated thermal lesion formation was investigated in vitro. PSNE containing dodecafluoropentane were produced with narrow size distributions and mean diameters below 200 nm using a combination of sonication and extrusion. PSNE was dispersed in albumin-containing polyacrylamide gel phantoms for experimental tests. Albumin denatures and becomes opaque at temperatures above 58°C, enabling visual detection of lesions formed from denatured albumin. PSNE were vaporized using a 30-cycle, 3.2-MHz, at an acoustic power of 6.4 W (free-field intensity of 4,586 W/cm(2)) pulse from a single-element, focused high-power transducer. The vaporization pulse was immediately followed by a 15-s continuous wave, 3.2-MHz signal to induce ultrasound-mediated heating. Control experiments were conducted using an identical procedure without the vaporization pulse. Lesion formation was detected by acquiring video frames during sonication and post-processing the images for analysis. Broadband emissions from inertial cavitation (IC) were passively detected with a focused, 2-MHz transducer. Temperature measurements were acquired using a needle thermocouple. Bubbles formed at the HIFU focus via PSNE vaporization enhanced HIFU-mediated heating

  17. Fabrication of single-phase ε-GaSe films on Si(100) substrate by metal organic chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chia-Chen; Zeng, Jia-Xian; Lan, Shan-Ming [Department of Electronic Engineering, College of Electrical Engineering and Computer Science, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Uen, Wu-Yih, E-mail: uenwuyih@ms37.hinet.net [Department of Electronic Engineering, College of Electrical Engineering and Computer Science, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Liao, Sen-Mao [Department of Electronic Engineering, College of Electrical Engineering and Computer Science, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Yang, Tsun-Neng; Ma, Wei-Yang [Institute of Nuclear Energy Research, P.O. Box 3-11, Lungtan 32500, Taiwan (China); Chang, Kuo-Jen [Chung-Shan Institute of Science and Technology, No.15, Shi Qi Zi, Gaoping Village, Longtan Township, Taoyuan County, Taiwan (China)

    2013-09-02

    Single-phase ε-gallium selenide (GaSe) films were fabricated on Si(100) substrate by metal organic chemical vapor deposition using dual-source precursors: triethylgallium (TEG) and hydrogen selenide (H{sub 2}Se) with the flow ratio of [H{sub 2}Se]/[TEG] being maintained at 1.2. In particular, an arsine (AsH{sub 3}) flow was introduced to the Si substrate before the film deposition to induce an arsenic (As)-passivation effect on the substrate. The crystalline structure of GaSe films prepared was analyzed using X-ray diffraction and the surface morphology of them was characterized by scanning electron microscopy. It was found that the film quality could be improved by the As-passivation effect. The optical properties of the films were studied by temperature dependent photoluminescence (PL) measurements. PL spectra obtained with different distributions and intensities favored for resolving the superior material quality of the films produced on the substrate with As-passivation compared to those produced on the substrate without As-passivation. The former was dominated by the excitonic emissions for the whole temperature range of 20–300 K examined, while the latter was initially dominated by the defect-related emission at 1.907 eV for a low-temperature range ≦ 80 K and then became dominated by the weak excitonic emission band instead. The ε modification of GaSe films prepared was further recognized by the Raman scattering measurements conducted at room temperature. - Highlights: • Gallium selenide (GaSe) layered structures are fabricated on Si(100) substrate. • Metal–organic chemical vapor deposition is used for film fabrication. • Arsenic-passivation effects of Si substrate on the GaSe film quality are analyzed. • Photoluminescence measurements of GaSe polycrystals are reported.

  18. Enthalpy of vaporization and vapor pressure of whiskey lactone and menthalactone by correlation gas chromatography

    International Nuclear Information System (INIS)

    Simmons, Daniel; Chickos, James

    2017-01-01

    Highlights: • The vapor pressure and vaporization enthalpies of cis and trans-whiskey lactone have been evaluated. • Enthalpies of vaporization and vapor pressures of (+)-isomintlactone and (−)-mintlactone were also evaluated. • The sublimation enthalpy and corresponding vapor pressure of (+) -isomintlactone at T = 298.15 K is estimated. - Abstract: Enthalpies of vaporization at T = 298.15 K of cis and trans-whiskey lactone have been evaluated by correlation gas chromatography to be (68.4 ± 1.7) kJ·mol −1 and (67.5 ± 1.7) kJ·mol −1 , respectively. The enthalpies of vaporization of isomintlactone and mintlactone also evaluated by correlation gas chromatography have been found to have vaporization enthalpies of (74.2 ± 1.8) kJ·mol −1 and (73.2 ± 1.8) kJ·mol −1 respectively. The vapor pressures for cis and trans-whiskey lactone at T = 298.15 K have been evaluated as (1.5 ± 0.09) Pa and (2.0 ± 0.1) Pa using vapor pressures of a series of lactones as standards. Vapor pressures for isomintlactone and mintlactone were evaluated as (0.26 ± 0.012) Pa and (0.33 ± 0.02) Pa, respectively. Fusion and sublimation enthalpies for (+)-isomintlactone as well as the vapor pressure of the solid have been estimated.

  19. Results of vapor space monitoring of flammable gas Watch List tanks

    International Nuclear Information System (INIS)

    Wilkins, N.E.

    1997-01-01

    This report documents the measurement of headspace gas concentrations and monitoring results from the Hanford tanks that have continuous flammable gas monitoring. The systems used to monitor the tanks are Standard Hydrogen Monitoring Systems. Further characterization of the tank off-gases was done with Gas Characterization Systems and vapor grab samples. The background concentrations of all tanks are below the action level of 6250 ppm. Other information which can be derived from the measurements (such as generation rate, release rate, and ventilation rate) is also discussed

  20. Process for carbonizing, distilling, and vaporizing of coal from any source

    Energy Technology Data Exchange (ETDEWEB)

    Limberg, T

    1916-10-15

    A process is described for carbonizing, distilling, and vaporizing coal from any source, especially of humid and bituminous coals as well as bituminous shale and peat for recovering an especially light tar with a large aliphatic hydrocarbon content that is characterized in that it is exposed to internal heating under vacuum at a temperature below dull-red heat. The distillation products of the material are washed away by the heating gases for the whole length of the furnace and are removed immediately and carried into separate condensers.

  1. Results of Vapor Space Monitoring of Flammable Gas Watch List Tanks

    Energy Technology Data Exchange (ETDEWEB)

    MCCAIN, D.J.

    2000-09-27

    This report documents the measurement of headspace gas concentrations and monitoring results from the Hanford tanks that have continuous flammable gas monitoring. The systems used to monitor the tanks are Standard Hydrogen Monitoring Systems. Further characterization of the tank off-gases was done with Gas Characterization systems and vapor grab samples. The background concentrations of all tanks are below the action level of 6250 ppm. Other information which can be derived from the measurements (such as generation rate, released rate, and ventilation rate) is also discussed.

  2. Data Quality Issues Associated with the Presence of Chlorinated Hydrocarbons in Tank Vapor Samples

    International Nuclear Information System (INIS)

    Evans, John C.; Huckaby, James L.

    2006-01-01

    Characterization data for the gases and vapors in the Hanford Site high-level radioactive waste tank headspaces are compiled and available via the TWINS interface (TWINS 2006). A recent re-examination of selected data from TWINS has shown a number of anomalies with respect to compounds that are (1) not expected to be present in the tank based on operational knowledge and (2) not found consistently in the same tank by alternative analysis methods or repeat sampling. Numerous results for two chemicals in particular, cis- and trans-1,2-dichloropropane, are determined here to be suspect based on evidence that they were laboratory contaminants

  3. A kinetic and equilibrium analysis of silicon carbide chemical vapor deposition on monofilaments

    Science.gov (United States)

    Gokoglu, S. A.; Kuczmarski, M. A.

    1993-01-01

    Chemical kinetics of atmospheric pressure silicon carbide (SiC) chemical vapor deposition (CVD) from dilute silane and propane source gases in hydrogen is numerically analyzed in a cylindrical upflow reactor designed for CVD on monofilaments. The chemical composition of the SiC deposit is assessed both from the calculated total fluxes of carbon and silicon and from chemical equilibrium considerations for the prevailing temperatures and species concentrations at and along the filament surface. The effects of gas and surface chemistry on the evolution of major gas phase species are considered in the analysis.

  4. Control of Self Burning in Coal, Piles by Detection of the generated gases; Control de autoencendidos en Parvas de Carbon por Deteccion de los Gases Producidos

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    The purpose of this Research Project is to find the most appropriate method for immediate and remote detection of the phenomena that take place in Thermic Power Plant coal piles, due to the piling up of great quantities of this fuel and its large surface area. These phenomena are: Slow self-oxidation of the coal, producing loss of its calorific power, with its consequent financial loss. Self-combustion of the coal caused when the gases produced by self-oxidation and temperature conditions combine, and they reach a critical point (that of ignition). One of the most recent and novel methods for detection is the Formation of images of Gases, based on the use of laser turned into the vibration wavelengths of the molecules in the gases. This technique, coupled with Thermography, would give as a spatial map of thus distribution and temperatures of gave. It is necessary, in order to extend the use of this equipment to Thermic Power Plant coal piles, to accurately determine which different gases are emanated as well as the minimum concentration of each one of these and the temperature distribution in space. (Author)

  5. Radiation and combined heat transfer in channels

    International Nuclear Information System (INIS)

    Tamonis, M.

    1986-01-01

    This book presents numerical methods of calculation of radiative and combined heat transfer in channel flows of radiating as well as nonradiating media. Results obtained in calculations for flow conditions of combustion products from organic fuel products are given and methods used in determining the spectral optical properties of molecular gases are analyzed. The book presents applications of heat transfer in solving problems. Topic covered are as follows: optical properties of molecular gases; transfer equations for combined heat transfer; experimental technique; convective heat transfer in heated gas flows; radiative heat transfer in gaseous media; combined heat transfer; and radiative and combined heat transfer in applied problems

  6. A low aspect ratio electrothermal gun for metal plasma vapor discharge and ceramic nanopowder production

    International Nuclear Information System (INIS)

    Kim, Kyoung Jin; Peterson, Dennis R.

    2008-01-01

    Traditionally, the electrothermal gun design has the bore of a large aspect ratio: however, a low aspect ratio design with a shorter bore length has been employed for efficient production of metal plasma vapors and synthesis of nanomaterials. In a comparison of the arc resistance-current relationship, a low aspect ratio design is found to exhibit distinctively different characteristics compared to a high aspect ratio design, and this trend is explained by the scaling law of plasma properties including theory of plasma electrical conductivity. A one-dimensional isothermal model has been applied to the present experiments to confirm the scaling laws, and it was found that the present modification of the electrothermal gun is able to produce fully ionized metal plasma vapor, while the plasma vapor produced in a conventional design is partially ionized. Also, by reacting metal plasma vapors with the controlled gases in the reaction chamber, nanoscale materials such as aluminum oxide, aluminum nitride, and titanium oxide were synthesized successfully

  7. Optical Sensor for Diverse Organic Vapors at ppm Concentration Ranges

    Directory of Open Access Journals (Sweden)

    Dora M. Paolucci

    2011-03-01

    Full Text Available A broadly responsive optical organic vapor sensor is described that responds to low concentrations of organic vapors without significant interference from water vapor. Responses to several classes of organic vapors are highlighted, and trends within classes are presented. The relationship between molecular properties (vapor pressure, boiling point, polarizability, and refractive index and sensor response are discussed.

  8. Wave speeds in the macroscopic extended model for ultrarelativistic gases

    Energy Technology Data Exchange (ETDEWEB)

    Borghero, F., E-mail: borghero@unica.it [Dip. Matematica e Informatica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy); Demontis, F., E-mail: fdemontis@unica.it [Dip. Matematica, Università di Cagliari, Viale Merello 92, 09123 Cagliari (Italy); Pennisi, S., E-mail: spennisi@unica.it [Dip. Matematica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy)

    2013-11-15

    Equations determining wave speeds for a model of ultrarelativistic gases are investigated. This model is already present in literature; it deals with an arbitrary number of moments and it was proposed in the context of exact macroscopic approaches in Extended Thermodynamics. We find these results: the whole system for the determination of the wave speeds can be divided into independent subsystems which are expressed by linear combinations, through scalar coefficients, of tensors all of the same order; some wave speeds, but not all of them, are expressed by square roots of rational numbers; finally, we prove that these wave speeds for the macroscopic model are the same of those furnished by the kinetic model.

  9. Thermoelectric transport and Peltier cooling of cold atomic gases

    Science.gov (United States)

    Grenier, Charles; Kollath, Corinna; Georges, Antoine

    2016-12-01

    This brief review presents the emerging field of mesoscopic physics with cold atoms, with an emphasis on thermal and 'thermoelectric' transport, i.e. coupled transport of particles and entropy. We review in particular the comparison between theoretically predicted and experimentally observed thermoelectric effects in such systems. We also show how combining well-designed transport properties and evaporative cooling leads to an equivalent of the Peltier effect with cold atoms, which can be used as a new cooling procedure with improved cooling power and efficiency compared to the evaporative cooling currently used in atomic gases. This could lead to a new generation of experiments probing strong correlation effects of ultracold fermionic atoms at low temperatures.

  10. Characterization of the TIP4P-Ew water model: vapor pressure and boiling point.

    Science.gov (United States)

    Horn, Hans W; Swope, William C; Pitera, Jed W

    2005-11-15

    The liquid-vapor-phase equilibrium properties of the previously developed TIP4P-Ew water model have been studied using thermodynamic integration free-energy simulation techniques in the temperature range of 274-400 K. We stress that free-energy results from simulations need to be corrected in order to be compared to the experiment. This is due to the fact that the thermodynamic end states accessible through simulations correspond to fictitious substances (classical rigid liquids and classical rigid ideal gases) while experiments operate on real substances (liquids and real gases, with quantum effects). After applying analytical corrections the vapor pressure curve obtained from simulated free-energy changes is in excellent agreement with the experimental vapor pressure curve. The boiling point of TIP4P-Ew water under ambient pressure is found to be at 370.3+/-1.9 K, about 7 K higher than the boiling point of TIP4P water (363.7+/-5.1 K; from simulations that employ finite range treatment of electrostatic and Lennard-Jones interactions). This is in contrast to the approximately +15 K by which the temperature of the density maximum and the melting temperature of TIP4P-Ew are shifted relative to TIP4P, indicating that the temperature range over which the liquid phase of TIP4P-Ew is stable is narrower than that of TIP4P and resembles more that of real water. The quality of the vapor pressure results highlights the success of TIP4P-Ew in describing the energetic and entropic aspects of intermolecular interactions in liquid water.

  11. Vaporization and thermodynamics of forsterite-rich olivine and some implications for silicate atmospheres of hot rocky exoplanets

    Science.gov (United States)

    Costa, Gustavo C. C.; Jacobson, Nathan S.; Fegley, Bruce, Jr.

    2017-06-01

    We describe an experimental and theoretical study of olivine [Mg2SiO4 (Fo)-Fe2SiO4 (Fa)] vaporization. The vaporization behavior and thermodynamic properties of a fosterite-rich olivine (Fo95Fa5) have been explored by high-temperature Knudsen effusion mass spectrometry (KEMS) from 1750 to 2250 K. The gases observed (in order of decreasing partial pressure) are Fe, SiO, Mg, O2 and O. We measured the solidus temperature (∼2050 K), partial pressures of individual gases, the total vapor pressure, and thermodynamic activities and partial molar enthalpies of MgO, 'FeO', and SiO2 for the Fo95Fa5 olivine. The results are compared to other measurements and models of the olivine system. Our experimental data show olivine vaporizes incongruently. We discuss this system both as a psuedo-binary of Fo-Fa and a psuedo-ternary of MgO-'FeO'-SiO2. Iron/magnesium molar ratios in the sample before (∼0.05) and after (∼0.04) vaporization are consistent with the small positive deviations from ideality of fayalite (γ ∼ 1.17) in olivine of the composition studied (e.g., Nafziger and Muan, 1967). Our data for olivine + melt confirm prior theoretical models predicting fractional vaporization of Fe relative to Mg from molten silicates (Fegley and Cameron, 1987; Schaefer and Fegley, 2009; Ito et al., 2015). If loss of silicate atmospheres occurs from hot rocky exoplanets with magma oceans the residual planet may be enriched in magnesium relative to iron.

  12. KFeSbTe3: A quaternary chalcogenide aerogel for preferential adsorption of polarizable hydrocarbons and gases

    KAUST Repository

    Ahmed, Ejaz

    2015-01-01

    The first telluride-based quaternary aerogel KFeSbTe3 is synthesized by a sol-gel metathesis reaction between Fe(OAc)2 and K3SbTe3 in dimethyl formamide. The aerogel has an exceptionally large surface area 652 m2 g-1 which is amongst the highest reported for chalcogenide-based aerogels. This predominantly mesoporous material shows preferential adsorption for toluene vapors over cyclohexane or cyclopentane and CO2 over CH4 or H2. The remarkably high adsorption capacity for toluene (9.31 mmol g-1) and high selectivity for gases (CO2/H2: 121 and CO2/CH4: 75) suggest a potential use of such materials in adsorption-based separation processes for the effective purification of hydrocarbons and gases. © The Royal Society of Chemistry 2015.

  13. Vapor-phase biofiltration: Laboratory and field experience

    International Nuclear Information System (INIS)

    Evans, P.J.; Bourbonais, K.A.; Peterson, L.E.; Lee, J.H.; Laakso, G.L.

    1995-01-01

    Application of vapor-phase bioreactors (VPBs) to petroleum hydrocarbons is complicated by the different mass transfer characteristics of aliphatics and aromatics. Laboratory- and pilot-scale VPB studies were conducted to evaluate treatment of soil vapor extraction (SVE) off-gas. A mixture of compost, perlite, and activated carbon was the selected medium based on pressure drop, microbial colonization, and adsorption properties. Two different pilot-scale reactors were built with a difference of 70:1 in scale. The smaller VPB's maximum effective elimination capacity (EC) was determined to be 7.2 g m -3 h -1 ; the larger unit's EC was 70% to 80% of this value. Low EC values may be attributable to a combination of mass-transfer and kinetic limitations

  14. Kinetic theory of nonideal gases and nonideal plasmas

    CERN Document Server

    Klimontovich, Yu L

    2013-01-01

    Kinetic Theory of Nonideal Gases and Nonideal Plasmas presents the fundamental aspects of the kinetic theory of gases and plasmas. The book consists of three parts, which attempts to present some of the ideas, methods and applications in the study of the kinetic processes in nonideal gases and plasmas. The first part focuses on the classical kinetic theory of nonideal gases. The second part discusses the classical kinetic theory of fully ionized plasmas. The last part is devoted to the quantum kinetic theory of nonideal gases and plasmas. A concluding chapter is included, which presents a shor

  15. Measurement of alkali-vapor emission from pressurized fluidized-bed combustion of Illinois coals

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.H.D.; Teats, F.G.; Swift, W.M. (Argonne National Lab., IL (United States)); Banerjee, D.D. (Illinois Clean Coal Inst., Carterville, IL (United States))

    1993-01-01

    Two Illinois Herrin No. 6 coals and one Illinois Springfield No. 5 coal were separately combusted in a laboratory-scale (15-cm dia) pressurized fluidized-bed combustor (PFBC) combined with an alkali sorber. These coals were combusted in a fluidized bed of Tymochtee dolomite at temperatures ranging from 910 to 950[degree]C and a system pressure of 9.2 atm absolute. Alkali-vapor emission (Na and K) in the PFBC flue gas was determined by the analytical activated-bauxite sorber bed technique developed at Argonne National Laboratory. The test results showed that sodium is the major alkali-vapor species present in the PFBC flue gas, and that the level of sodium-vapor emission increases linearly with both Na and Cl contents in the coals. This suggests that the sodium-vapor emission results from direct vaporization of NaCl present in the coals. The measured alkali-vapor concentration (Na + K), 67 to 190 ppbW, is more than 2.5 times greater than the allowable alkali limit of 24 ppb for an industrial gas turbine. Combusting these coals in a PFBC for power generation may require developing a method to control alkali vapors.

  16. Measurement of alkali-vapor emission from pressurized fluidized-bed combustion of Illinois coals

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.H.D.; Teats, F.G.; Swift, W.M. [Argonne National Lab., IL (United States); Banerjee, D.D. [Illinois Clean Coal Inst., Carterville, IL (United States)

    1993-04-01

    Two Illinois Herrin No. 6 coals and one Illinois Springfield No. 5 coal were separately combusted in a laboratory-scale (15-cm dia) pressurized fluidized-bed combustor (PFBC) combined with an alkali sorber. These coals were combusted in a fluidized bed of Tymochtee dolomite at temperatures ranging from 910 to 950{degree}C and a system pressure of 9.2 atm absolute. Alkali-vapor emission (Na and K) in the PFBC flue gas was determined by the analytical activated-bauxite sorber bed technique developed at Argonne National Laboratory. The test results showed that sodium is the major alkali-vapor species present in the PFBC flue gas, and that the level of sodium-vapor emission increases linearly with both Na and Cl contents in the coals. This suggests that the sodium-vapor emission results from direct vaporization of NaCl present in the coals. The measured alkali-vapor concentration (Na + K), 67 to 190 ppbW, is more than 2.5 times greater than the allowable alkali limit of 24 ppb for an industrial gas turbine. Combusting these coals in a PFBC for power generation may require developing a method to control alkali vapors.

  17. Methods of forming and using porous structures for energy efficient separation of light gases by capillary condensation

    Science.gov (United States)

    Calamur, Narasimhan; Carrera, Martin E.; Devlin, David J.; Archuleta, Tom

    2000-01-01

    The present invention relates to an improved method and apparatus for separating one or more condensable compounds from a mixture of two or more gases of differing volatilities by capillary fractionation in a membrane-type apparatus, and a method of forming porous structures therefor. More particularly, the invention includes methods of forming and using an apparatus consisting, at least in part, of a porous structure having capillary-type passages extending between a plurality of small openings on the first side and larger openings on a second side of the structure, the passages being adapted to permit a condensed liquid to flow therethrough substantially by capillary forces, whereby vapors from the mixture are condensed, at least in part, and substantially in and adjacent to the openings on the first side, and are caused to flow in a condensed liquid state, substantially in the absence of vapor, from the openings on the first side to the openings on the second side.

  18. Atomic vapor laser isotope separation

    International Nuclear Information System (INIS)

    Stern, R.C.; Paisner, J.A.

    1985-01-01

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements

  19. SOIL VAPOR EXTRACTION TECHNOLOGY: REFERENCE HANDBOOK

    Science.gov (United States)

    Soil vapor extraction (SVE) systems are being used in Increasing numbers because of the many advantages these systems hold over other soil treatment technologies. SVE systems appear to be simple in design and operation, yet the fundamentals governing subsurface vapor transport ar...

  20. Vapor Pressures of Several Commercially Used Alkanolamines

    NARCIS (Netherlands)

    Klepacova, Katarina; Huttenhuis, Patrick J. G.; Derks, Peter W. J.; Versteeg, Geert F.; Klepáčová, Katarína

    For the design of acid gas treating processes, vapor-liquid equilibrium (VLE) data must be available of the solvents to be applied. In this study the vapor pressures of seven frequently industrially used alkanolamines (diethanolamine, N-methylethanolamine, N,N-dimethylethanolamine,

  1. Recommended Vapor Pressure of Solid Naphthalen

    Czech Academy of Sciences Publication Activity Database

    Růžička, K.; Fulem, Michal; Růžička, V.

    2005-01-01

    Roč. 50, - (2005), s. 1956-1970 ISSN 0021-9568 Institutional research plan: CEZ:AV0Z10100521 Keywords : solid naphthalene * vapor pressure * enthalpy of vaporization * enthalpy of fusion Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.610, year: 2005

  2. Effect of granosan vapors on mitosis

    Energy Technology Data Exchange (ETDEWEB)

    Lishenko, N P; Lishenko, I D

    1974-01-01

    Experiments were performed to determine the effects of granosan on the germination of vetch seeds. Vetch seeds were stored from 4-6 days in ethyl mercuric chloride vapors. Results indicated that the vapors caused a sharp decrease in germination and caused chromosomal aberrations during the anaphase.

  3. Condensation of vapor bubble in subcooled pool

    Science.gov (United States)

    Horiuchi, K.; Koiwa, Y.; Kaneko, T.; Ueno, I.

    2017-02-01

    We focus on condensation process of vapor bubble exposed to a pooled liquid of subcooled conditions. Two different geometries are employed in the present research; one is the evaporation on the heated surface, that is, subcooled pool boiling, and the other the injection of vapor into the subcooled pool. The test fluid is water, and all series of the experiments are conducted under the atmospheric pressure condition. The degree of subcooling is ranged from 10 to 40 K. Through the boiling experiment, unique phenomenon known as microbubble emission boiling (MEB) is introduced; this phenomenon realizes heat flux about 10 times higher than the critical heat flux. Condensation of the vapor bubble is the key phenomenon to supply ambient cold liquid to the heated surface. In order to understand the condensing process in the MEB, we prepare vapor in the vapor generator instead of the evaporation on the heated surface, and inject the vapor to expose the vapor bubble to the subcooled liquid. Special attention is paid to the dynamics of the vapor bubble detected by the high-speed video camera, and on the enhancement of the heat transfer due to the variation of interface area driven by the condensation.

  4. Risk assessment of metal vapor arcing

    Science.gov (United States)

    Hill, Monika C. (Inventor); Leidecker, Henning W. (Inventor)

    2009-01-01

    A method for assessing metal vapor arcing risk for a component is provided. The method comprises acquiring a current variable value associated with an operation of the component; comparing the current variable value with a threshold value for the variable; evaluating compared variable data to determine the metal vapor arcing risk in the component; and generating a risk assessment status for the component.

  5. Treatment and separation of radioactive fission products tritium, rare gases and iodine in nuclear fuel reprocessing plants

    Energy Technology Data Exchange (ETDEWEB)

    Schnez, H.

    1975-07-15

    Rare gases must be separated from the process off-gases of the head-end of the Purex and Thorex processes. To achieve high decontamination factors, the quantity of off-gas should be kept as low as possible. For rare gas separation, there are two possible methods of routing the off-gas: (a) the open flushing gas circuit, in which the purified off-gas (generally air) is passed off via the stack and (b) the closed circuit in which the off-gas (nitrogen or rare gases) is recycled to the dissolver after purification. Tritium must not be entrained into the second extraction cycle or be emitted with off-gases in the form of water vapor (HTO) or HT, but must remain completely in the aqueous phase. Most of the process water is recycled, as a result of which the tritium becomes concentrated in it. This tritiated water is then subjected to tritium rectification at a suitable point in the process. Iodine is very difficult to isolate to a small number of process stages. Present aim is to release the iodine in the dissolver stage into the off-gas, so as to prevent it being entrained into the extraction part. By the injection of hot nitrogen or water vapor into the dissolver or into iodine-containing condensates, all of the iodine is passed into the gaseous phase. Scrubbers can also be used together with iodine-containing condensates to adjust the scrubbing solution. Capital cost of separation plants account for 1 to 10 percent of the total cost of the reprocessing installation, and even more if a sophisticated tritium separation system is required. (DLC)

  6. A research program on radiative, chemical, and dynamical feedback progresses influencing the carbon dioxide and trace gases climate effects

    International Nuclear Information System (INIS)

    1989-07-01

    This report summarizes the up-to-date progress. The program includes two tasks: atmospheric radiation and climatic effects and their objective is to link quantitatively the radiation forcing changes and the climate responses caused by increasing greenhouse gases. Here, the objective and approach are described. We investigate the combined atmospheric radiation characteristics of the greenhouse gases (H 2 O, CO 2 , CH 4 , N 2 O, CFCs, and O 3 ), aerosols and clouds. Since the climatic effect of increasing atmospheric greenhouse gases is initiated by perturabtion to the longwave thermal radiation, it is critical to understand better the radiation characteristics of the greenhouse gases and their relationship to radiatively-important aerosols and clouds; the latter reflect solar radiation (a cooling of the surface) and provide a greenhouse effect (a warming to the surface). Therefore, aerosol and cloud particles are an integral part of the radiation field in the atmosphere. 9 refs

  7. Building blocks for ionic liquids: Vapor pressures and vaporization enthalpies of 1-(n-alkyl)-imidazoles

    International Nuclear Information System (INIS)

    Emel'yanenko, Vladimir N.; Portnova, Svetlana V.; Verevkin, Sergey P.; Skrzypczak, Andrzej; Schubert, Thomas

    2011-01-01

    Highlights: → We measured vapor pressures of the 1-(n-alkyl)-imidazoles by transpiration method. → Variations on the alkyl chain length n were C 3 , C 5 -C 7 , and C 9 -C 10 . → Enthalpies of vaporization were derived from (p, T) dependencies. → Enthalpies of vaporization at 298.15 K were linear dependent on the chain length. - Abstract: Vapor pressures of the linear 1-(n-alkyl)-imidazoles with the alkyl chain C 3 , C 5 -C 7 , and C 9 -C 10 have been measured by the transpiration method. The molar enthalpies of vaporization Δ l g H m of these compounds were derived from the temperature dependencies of vapor pressures. A linear correlation of enthalpies of vaporization Δ l g H m (298.15 K) of the 1-(n-alkyl)-imidazoles with the chain length has been found.

  8. Detecting and Identifying Industrial Gases by a Method Based on Olfactory Machine at Different Concentrations

    Directory of Open Access Journals (Sweden)

    Yunlong Sun

    2018-01-01

    Full Text Available Gas sensors have been widely reported for industrial gas detection and monitoring. However, the rapid detection and identification of industrial gases are still a challenge. In this work, we measure four typical industrial gases including CO2, CH4, NH3, and volatile organic compounds (VOCs based on electronic nose (EN at different concentrations. To solve the problem of effective classification and identification of different industrial gases, we propose an algorithm based on the selective local linear embedding (SLLE to reduce the dimensionality and extract the features of high-dimensional data. Combining the Euclidean distance (ED formula with the proposed algorithm, we can achieve better classification and identification of four kinds of gases. We compared the classification and recognition results of classical principal component analysis (PCA, linear discriminate analysis (LDA, and PCA + LDA algorithms with the proposed SLLE algorithm after selecting the original data and performing feature extraction. The experimental results show that the recognition accuracy rate of the SLLE reaches 91.36%, which is better than the other three algorithms. In addition, the SLLE algorithm provides more efficient and accurate responses to high-dimensional industrial gas data. It can be used in real-time industrial gas detection and monitoring combined with gas sensor networks.

  9. Irradiation technologies used for combustion gases and diluted sulfurous gases decontamination

    International Nuclear Information System (INIS)

    Villanueva Z, Loreto

    1998-01-01

    A brief description of irradiation technology used for ambient decontamination is presented here. The system is adequate fort gas and liquid effluents and solid wastes. In particular, the characteristics and applications of the irradiation done with an electron beam to gas effluent is described, mainly to clean combustion gases and other industrial gases containing sulfur and nitrogen oxides, S O x and N O x , respectively. This technology permits the remove of these contaminants and the acquisition of a solid byproduct, an ammonia sulfate-nitrate, apt for fertilizer applications. (author)

  10. Diffusive retention of atmospheric gases in chert

    Science.gov (United States)

    Pettitt, E.; Cherniak, D. J.; Watson, E. B.; Schaller, M. F.

    2016-12-01

    Throughout Earth's history, the volatile contents (N2, CO2, Ar) of both deep and shallow terrestrial reservoirs has been dynamic. Volatiles are important chemical constituents because they play a significant role in regulating Earth's climate, mediating the evolution of complex life, and controlling the properties of minerals and rocks. Estimating levels of atmospheric volatiles in the deep geological past requires interrogation of materials that have acquired and retained a chemical memory from that time. Cherts have the potential to trap atmospheric components during formation and later release those gases for analysis in the laboratory. However, cherts have been underexploited in this regard, partly because their ability to retain a record of volatile components has not been adequately evaluated. Before cherts can be reliably used as indicators of past levels of major atmospheric gases, it is crucial that we understand the diffusive retentiveness of these cryptocrystalline silica phases. As the first step toward quantifying the diffusivity and solubility of carbon dioxide and nitrogen in chert, we have performed 1-atmosphere diffusive-uptake experiments at temperatures up to 450°C. Depth profiles of in-diffusing gases are measured by nuclear reaction analysis (NRA) to help us understand the molecular-scale transport of volatiles and thus the validity of using chert-bound volatiles to record information about Earth history. Data collected to date suggest that at least some cherts are ideal storage containers and can retain volatiles for a geologically long time. In addition to these diffusion experiments, preliminary online-crush fast-scan measurements using a quadrupole mass spectrometer indicate that atmospheric volatiles are released upon crushing various chert samples. By coupling such volatile-release measurements made by mass spectrometry with diffusion experiments, we are uniquely able to address the storage and fidelity of volatiles bound in crustal

  11. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Tank 241-TY-102: Results from samples collected on 04/12/96

    International Nuclear Information System (INIS)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-TY-102 (Tank TY-102) at the Hanford Site in Washington State. The results described in this report were obtained to'characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes, and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices

  12. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Tank 241-B-105: Results from samples collected on 07/30/96

    International Nuclear Information System (INIS)

    Pool, K.H.; Evans, J.C.; Thomas, B.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-B-105 (Tank B-105) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices

  13. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Waste Tank 241-S-103: Results from samples collected on 06/12/96

    International Nuclear Information System (INIS)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-S-103 (Tank S-103) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices

  14. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Waste Tank 241-C-204: Results from samples collected on 07/02/96

    International Nuclear Information System (INIS)

    Thomas, B.L.; Evans, J.C.; Pool, K.H.

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-C-204 (Tank C-204) at the Hanford Site in Washington State. The results described in this report were obtained to characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. The three highest concentration analytes detected in SUMMA trademark canister and triple sorbent trap samples are also listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices

  15. A differential absorption technique to estimate atmospheric total water vapor amounts

    Science.gov (United States)

    Frouin, Robert; Middleton, Elizabeth

    1990-01-01

    Vertically integrated water-vapor amounts can be remotely determined by measuring the solar radiance reflected by the earth's surface with satellites or aircraft-based instruments. The technique is based on the method by Fowle (1912, 1913) and utilizes the 0.940-micron water-vapor band to retrieve total-water-vapor data that is independent of surface reflectance properties and other atmospheric constituents. A channel combination is proposed to provide more accurate results, the SE-590 spectrometer is used to verify the data, and the effects of atmospheric photon backscattering is examined. The spectrometer and radiosonde data confirm the accuracy of using a narrow and a wide channel centered on the same wavelength to determine water vapor amounts. The technique is suitable for cloudless conditions and can contribute to atmospheric corrections of land-surface parameters.

  16. Thermodynamic functions and vapor pressures of uranium and plutonium oxides at high temperatures

    International Nuclear Information System (INIS)

    Green, D.W.; Reedy, G.T.; Leibowitz, L.

    1977-01-01

    The total energy release in a hypothetical reactor accident is sensitive to the total vapor pressure of the fuel. Thermodynamic functions which are accurate at high temperature can be calculated with the methods of statistical mechanics provided that needed spectroscopic data are available. This method of obtaining high-temperature vapor pressures should be greatly superior to the extrapolation of experimental vapor pressure measurements beyond the temperature range studied. Spectroscopic data needed for these calculations are obtained from infrared spectroscopy of matrix-isolated uranium and plutonium oxides. These data allow the assignments of the observed spectra to specific molecular species as well as the calculation of anharmonicities for monoxides, bond angles for dioxides, and molecular geometries for trioxides. These data are then employed, in combination with data on rotational and electronic molecular energy levels, to determine thermodynamic functions that are suitable for the calculation of high-temperature vapor pressures

  17. Method for detecting trace impurities in gases

    Science.gov (United States)

    Freund, S.M.; Maier, W.B. II; Holland, R.F.; Beattie, W.H.

    A technique for considerably improving the sensitivity and specificity of infrared spectrometry as applied to quantitative determination of trace impurities in various carrier or solvent gases is presented. A gas to be examined for impurities is liquefied and infrared absorption spectra of the liquid are obtained. Spectral simplification and number densities of impurities in the optical path are substantially higher than are obtainable in similar gas-phase analyses. Carbon dioxide impurity (approx. 2 ppM) present in commercial Xe and ppM levels of Freon 12 and vinyl chloride added to liquefied air are used to illustrate the method.

  18. Positron scattering from noble gases future prospects

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A C L; Caradonna, P; Makochekanwa, C; Slaughter, D S; Sullivan, J P; Buckman, S J [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, Australian National University, Canberra, ACT (Australia); Mitroy, J, E-mail: acj107@rsphysse.anu.edu.a [Faculty of Education Health and Science, Charles Darwin University, NT (Australia)

    2009-11-01

    Recent results for positron scattering from noble gases over an energy range from 0.5 to 60eV are presented. Measurements include the grand total ({sigma}{sub GT}), Ps formation ({sigma}{sub Ps}) and Grand total - Ps formation (({sigma}{sub GT}-P{sub s}) cross sections. Some preliminary DCS results will also be presented. Work on a formulation of modified effective range theory (MERT) is being undertaken to determine the value of the scattering length which may be useful for identifying a bound state. Plans for experiments on metal atoms will be outlined.

  19. Characteristic of combustion of Colombian gases

    International Nuclear Information System (INIS)

    Gil B, Edison; Maya, Ruben; Andres, Amel A.

    1996-01-01

    The variety of gas locations in the country, makes that the gas that will be distributed by the net of present gas pipeline a very different composition, what bears to that these they behave in a different way during its use. In this work the main characteristics of the combustion are calculated for the Colombian gases, basically the properties of the combustion and the characteristics of the smoke, as basic information for the design and operation of the gas teams and their certification. These properties were calculated with the special help software for combustion developed by the authors

  20. Effect of Greenhouse Gases Dissolved in Seawater

    Directory of Open Access Journals (Sweden)

    Shigeki Matsunaga

    2015-12-01

    Full Text Available A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region.