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Sample records for gas condensation technique

  1. Off gas condenser performance modelling

    International Nuclear Information System (INIS)

    Cains, P.W.; Hills, K.M.; Waring, S.; Pratchett, A.G.

    1989-12-01

    A suite of three programmes has been developed to model the ruthenium decontamination performance of a vitrification plant off-gas condenser. The stages of the model are: condensation of water vapour, NO x absorption in the condensate, RuO 4 absorption in the condensate. Juxtaposition of these stages gives a package that may be run on an IBM-compatible desktop PC. Experimental work indicates that the criterion [HNO 2 ] > 10 [RuO 4 ] used to determine RuO 4 destruction in solution is probably realistic under condenser conditions. Vapour pressures of RuO 4 over aqueous solutions at 70 o -90 o C are slightly lower than the values given by extrapolating the ln K p vs. T -1 relation derived from lower temperature data. (author)

  2. Determination of Reasons of Obstruction in the Condensate Stabilizer System of Namconson Gas Treatment Terminal by Radioisotope Techniques

    International Nuclear Information System (INIS)

    Bui Quang Tri; Nguyen Huu Quang; Dang Nguyen The Duy; Tran Tri Hai; Tran Thanh Minh

    2008-01-01

    The Condensate Stabilizer System of Namconson Gas Treatment Terminal was designed with operational flow rate of 60 m 3 /h but for unknown reason it ran efficiently below 20 m 3 /h. The Radiotracer in combination with Gamma Scan was used to investigate in understanding the reasons. The results showed the build up at the bottom of Trap out Tray which caused obstruction of condensate flow in the outlet of Trap out Tray. As a results the feed flow rate to Reboiler from Trap out Tray lowered into 1/3 and the remaining 2/3 by passing the Reboiler by overflow to the Sump. (author)

  3. Gas manufacture, processes for: condensers

    Energy Technology Data Exchange (ETDEWEB)

    Young, W

    1876-11-29

    In the production of illuminating gas from coal, shale, hydrocarbon oil, or other substance used in the production of gas, the volatile products inside the retort are agitated by means of moving pistons or jets of compressed gas, steam, or vapor in order to decompose them into permanent gases, and in some cases to increase the volume of gas by the decomposition of the injected gas, etc. or by blending or carburetting this gas with the decomposition products of the volatile matters. To separate the condensible hydrocarbons from the crude gas it is passed through heated narrow tortuous passages or is caused to impinge on surfaces. If the crude gases are cold these surfaces are heated and vice versa.

  4. Investigation into the determination of trimethylarsine in natural gas and its partitioning into gas and condensate phases using (cryotrapping)/gas chromatography coupled to inductively coupled plasma mass spectrometry and liquid/solid sorption techniques

    International Nuclear Information System (INIS)

    Krupp, E.M.; Johnson, C.; Rechsteiner, C.; Moir, M.; Leong, D.; Feldmann, J.

    2007-01-01

    Speciation of trialkylated arsenic compunds in natural gas, pressurized and stable condensate samples from the same gas well was performed using (Cryotrapping) Gas Chromatography-Inductively Coupled Plasma Mass Spectrometry. The major species in all phases investigated was found to be trimethylarsine with a highest concentration of 17.8 ng/L (As) in the gas phase and 33.2 μg/L (As) in the stable condensate phase. The highest amount of trimethylarsine (121 μg/L (As)) was found in the pressurized condensate, along with trace amounts of non-identified higher alkylated arsines. Volatile arsenic species in natural gas and its related products cause concern with regards to environment, safety, occupational health and gas processing. Therefore, interest lies in a fast and simple field method for the determination of volatile arsenicals. Here, we use simple liquid and solid sorption techniques, namely absorption in silver nitrate solution and adsorption on silver nitrate impregnated silica gel tubes followed by total arsenic determination as a promising tool for field monitoring of volatile arsenicals in natural gas and gas condensates. Preliminary results obtained for the sorption-based methods show that around 70% of the arsenic is determined with these methods in comparison to volatile arsenic determination using GC-ICP-MS. Furthermore, an inter-laboratory- and inter-method comparison was performed using silver nitrate impregnated silica tubes on 14 different gas samples with concentrations varying from below 1 to 1000 μg As/m 3 natural gas. The results obtained from the two laboratories differ in a range of 10 to 60%, but agree within the order of magnitude, which is satisfactory for our purposes

  5. Study of flue gas condensers with reference to corrosion risks, biofuel quality, techniques and choice of material; Kartlaeggning av roekgaskondenseringsanlaeggningar med avseende paa korrosionsrisker, biobraenslekvaliteter, teknik och materialval

    Energy Technology Data Exchange (ETDEWEB)

    Stenqvist, Per-Aake

    2012-02-15

    Corrosion in flue gas appliances installed in small and medium sized biomass fired boiler plants has become a problem in an increasing number of sites around Sweden. A trend seems to be that the problems are greater in those plants that use so called terminal chips than those that utilize more homogeneous fuels. In pace with the increasing number of biomass power plants in the country, the demand for cheaper fuel is increased. Through the increasing number of fuel terminals the market is provided even with biofuel mixes in the form of traditional wood chips mixed with bark, forest residue, sawdust, willow, returned wood, etc. Both users and suppliers of boiler and flue gas systems, and fuel suppliers have currently no clear rules or guidelines for relationships between different chemical properties of fuels, technologies, operating data and material. In this report has experience in the form of questionnaires completed by field visits, interviews of operational personnel and literature studies been compiled from a number of plants using different types of flue gas condensers for increased energy output from various types of bio fuels. The purpose of this assignment is to survey the flue gas condensation plant in biomass fired boiler plants for the presence of corrosion damage made in relation to the use of technologies and fuel qualities. A milestone is that the report will be able to be used to support the selection of materials and appropriate techniques for both new facilities and for the repair and improvement of existing ones. Another objective is to compile existing experience and assessment criteria which are reported in the literature. This report describes some typical construction techniques, whenever applicable harmful images and links to various substances present in fuels, ash and condensate

  6. Sn and Cu oxide nanoparticles deposited on TiO{sub 2} nanoflower 3D substrates by Inert Gas Condensation technique

    Energy Technology Data Exchange (ETDEWEB)

    Kusior, A., E-mail: akusior@agh.edu.pl [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Kollbek, K. [Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Kowalski, K. [Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Borysiewicz, M. [Institute of Electron Technology, al. Lotnikow 32/46, 02-668 Warszawa (Poland); Wojciechowski, T. [Institute of Physics Polish Academy of Science, al. Lotnikow 32/46, 02-668 Warszawa (Poland); Adamczyk, A.; Trenczek-Zajac, A.; Radecka, M. [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland); Zakrzewska, K. [Faculty of Computer Science, Electronics and Telecommunications, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland)

    2016-09-01

    Graphical abstract: - Highlights: • Inert Gas Condensation method yields non-agglomerated nanoparticles. • The growth of nanoparticles is controllable at the level of deposition. • Electrical conductivity increases with respect to pure nanostructured TiO{sub 2}. - Abstract: Sn and Cu oxide nanoparticles were deposited by Inert Gas Condensation (IGC) technique combined with dc magnetron sputtering onto nanoflower TiO{sub 2} 3D substrates obtained in the oxidation process of Ti-foil in 30% H{sub 2}O{sub 2}. Sputtering parameters such as insertion length and Ar/He flow rates were optimized taking into account the nanostructure morphology. Comparative studies with hydrothermal method were carried out. Surface properties of the synthesized nanomaterials were studied by Scanning Electron Microscopy, SEM, Atomic Force Microscopy, AFM, and X-ray Photoelectron Spectroscopy, XPS. X-ray diffraction, XRD and Raman spectroscopy were performed in order to determine phase composition. Impedance spectroscopy demonstrated the influence of nanoparticles on the electrical conductivity.

  7. Applications of UT results to confirm defects findings by utilization of relevant metallurgical investigations techniques on gas/condensate pipeline working in wet sour gas environment

    Science.gov (United States)

    El-Azhari, O. A.; Gajam, S. Y.

    2015-03-01

    The gas/condensate pipe line under investigation is a 12 inch diameter, 48 km ASTM, A106 steel pipeline, carrying hydrocarbons containing wet CO2 and H2S.The pipe line had exploded in a region 100m distance from its terminal; after 24 years of service. Hydrogen induced cracking (HIC) and sour gas corrosion were expected due to the presence of wet H2S in the gas analysis. In other areas of pipe line ultrasonic testing was performed to determine whether the pipeline can be re-operated. The results have shown presence of internal planner defects, this was attributed to the existence of either laminations, type II inclusions or some service defects such as HIC and step wise cracking (SWC).Metallurgical investigations were conducted on fractured samples as per NACE standard (TM-0284-84). The obtained results had shown macroscopic cracks in the form of SWC, microstructure of steel had MnS inclusions. Crack sensitivity analyses were calculated and the microhardness testing was conducted. These results had confirmed that the line material was suffering from sour gas deteriorations. This paper correlates the field UT inspection findings with those methods investigated in the laboratory. Based on the results obtained a new HIC resistance material pipeline needs to be selected.

  8. Millstone 3 condensate dissolved gas monitoring

    International Nuclear Information System (INIS)

    Burns, T.F.; Grondahl, E.E.; Snyder, D.T.

    1988-01-01

    Condensate dissolved oxygen problems at Millstone Point Unit 3 (MP3) were investigated using the Dissolved Gas Monitoring System developed by Radiological and Chemical Technology, Inc. under EPRI sponsorship. Argon was injected into the turbine exhaust basket tips to perform a dissolved gas transport analysis and determine steam jet air ejector gas removal efficiency. The operating configuration of the steam jet air ejector system was varied to determine the effect on gas removal efficiency. Following circulating water chlorination, the gas removal efficiency was determined to evaluate the effect of condenser tube fouling on steam jet air ejector performance

  9. Using helical compressors for coke gas condensation

    Energy Technology Data Exchange (ETDEWEB)

    Privalov, V E; Rezunenko, Yu I; Lelyanov, N V; Zarnitzkii, G Eh; Gordienko, A A; Derebenko, I F; Venzhega, A G; Leonov, N P; Gorokhov, N N

    1982-08-01

    Coke oven gas compression is discussed. Presently used multilevel piston compressors are criticized. The paper recommends using helical machines which combine advantages of using volume condensing compressors and compact high-efficiency centrifugal machines. Two kinds of helical compressors are evaluated: dry and oil-filled; their productivities and coke oven gas chemical composition are analyzed. Experiments using helical compressors were undertaken at the Yasinovskii plant. Flowsheet of the installation is shown. Performance results are given in a table. For all operating conditions content of insolubles in oil compounds is found to be lower than the acceptable value (0.08%). Compressor productivity measurements with variable manifold pressure are evaluated. Figures obtained show that efficient condensation of raw coke oven gas is possible. Increasing oil-filled compressor productivity is recommended by decreasing amount of oil injected and simultaneously increasing rotation speed. The dry helical compressor with water seal is found to be most promising for raw coke oven gas condensation. (10 refs.)

  10. Effect on non-condensable gas on steam injector

    International Nuclear Information System (INIS)

    Kawamoto, Y.; Abe, Y.; Iwaki, C.; Narabayashi, T.; Mori, M.; Ohmori, S.

    2004-01-01

    Next-generation reactor systems have been under development aiming at simplified system and improvement of safety and credibility. A steam injector has a function of a passive pump without large motor or turbo-machinery, and has been investigated as one of the most important component of the next-generation reactor. Its performance as a pump depends on direct contact condensation phenomena between a supersonic steam and a sub-cooled water jet. Although non-condensable gases are well known for reducing heat transfer, the effect of the non-condensable gas on the condensation of supersonic steam on high-speed water jet has not been cleared. The present paper presents an experimental study of condensation of supersonic steam around turbulent water jet with model steam injector made by transparent plastic. The experimental apparatus is described. The visual observation was carried out by using high-speed camera. The non-condensable gas effect on the pump performance and flow characteristics are clarified by the image processing technique for the jet shape and gas-liquid interface behavior. (authors)

  11. Problems in operation of gas-oil condensate fields

    Energy Technology Data Exchange (ETDEWEB)

    Zheltov, Yu V; Martos, V N

    1966-12-01

    This is a review of various methods used to deplete gas-oil condensate reservoirs. Four depletion techniques are discussed: (1) natural depletion without injection of fluids into the reservoir; (2) depletion accompanied by gas cycling; (3) depletion in which the gas cap is separated from the oil by water injected into the reservoir, a method in which each part of the reservoir is produced essentially independently of the other; and (4) depletion in which reservoir temperature is raised above the cricondentherm point by in-situ combustion, so that gas and oil form a single phase. This method is prospective, and has not been tried in the field. Advantages and disadvantages of each method are discussed. It is concluded that a gas condensate reservoir can be depleted most economically only if some secondary energy is added. (13 refs.)

  12. Drilling of gas and condensed gas wells

    Energy Technology Data Exchange (ETDEWEB)

    Geranin, M P; Chao, P L; Lomonosov, V V

    1981-01-01

    Cementing of boreholes drilled into underground gas fields and the requirements imposed on the grouting mortar are reviewed. Results are set forth from a study of the insulation capacity of cementing mortar used to increase the quality of reinforcements of boreholes at PKhG. Data are presented on the properties of different grouting mortars for boreholes at PKhG, including those that may be used at low temperatures. Information is also provided on the use of light mortar containing a CaCl/sub 2/ additive, grouting mortar with furfuryl alcohol added, and expanding grouting mortars.

  13. Development of gas and gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    In the study of gas reservoir development, the first year topics are restricted on reservoir characterization. There are two types of reservoir characterization. One is the reservoir formation characterization and the other is the reservoir fluid characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. The results of conditional simulation has higher confidence level than the unconditional simulation because conditional simulation considers the sample location as well as distance correlation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. From the liquid volume fraction with pressure drop, the phase behavior of reservoir fluid can be estimated. The calculation results of fluid recombination, constant composition expansion, and constant volume depletion are matched very well with the experimental data. In swelling test of the reservoir fluid with lean gas, the accuracy of dew point pressure forecast depends on the component characterization. (author). 28 figs., 10 tabs.

  14. The Effect of Capillary Number on a Condensate Blockage in Gas Condensate Reservoirs

    OpenAIRE

    Saifon DAUNGKAEW; Alain C GRINGARTEN

    2004-01-01

    In the petroleum industry, gas condensate reservoirs are becoming more common as exploration targets. However, there is a lack of knowledge of the reservoir behaviour mainly due to its complexity in the near wellbore region, where two phases, i.e. reservoir gas and condensate coexist when the wellbore pressure drops below the dew point pressure. The condensation process causes a reduction of the gas productivity (1). It has been reported in the literature that there is an increasing gas mobil...

  15. Boiling, condensation, and gas-liquid flow

    International Nuclear Information System (INIS)

    Whalley, P.B.

    1987-01-01

    Heat transfer phenomena involving boiling and condensation are an important aspect of engineering in the power and process industries. This book, aimed at advanced first-degree and graduate students in mechanical and chemical engineering, deals with these phenomena in detail. The first part of the book describes gas-liquid two-phase flow, as a necessary preliminary to the later discussion of heat transfer and change of phase. A detailed section on calculation methods shows how theory can be put to practical use, and there are also descriptions of some of the equipment and plant used in the process and power industries

  16. Gas condensate reservoir performance : part 1 : fluid characterization

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, F.B.; Bennion, D.B. [Hycal Energy Research Laboratories Ltd., Calgary, AB (Canada); Andersen, G. [ChevronTexaco, Calgary, AB (Canada)

    2006-07-01

    Phase behaviour in gas condensate reservoirs is sensitive to changes in pressure and temperature, which can lead to significant errors in fluid characterization. The challenging task of characterizing in situ fluids in gas condensate reservoirs was discussed with reference to the errors that occur as a result of the complex coupling between phase behavior and geology. This paper presented techniques for reservoir sampling and characterization and proposed methods for minimizing errors. Errors are often made in the classification of dew point systems because engineering criteria does not accurately represent the phase behavior of the reservoir. For example, the fluid of a certain condensate yield may be categorized as a wet gas rather than a retrograde condensate fluid. It was noted that the liquid yield does not dictate whether the fluid is condensate or wet gas, but rather where the reservoir temperature is situated in the pressure temperature phase loop. In order to proceed with a viable field development plan and optimization, the reservoir fluid must be understood. Given that gas productivity decreases with liquid drop out in the near wellbore region, capillary pressure plays a significant role in retrograde reservoirs. It was noted that well understood parameters will lead to a better assessment of the amount of hydrocarbon in place, the rate at which the resource can be produced and optimization strategies as the reservoir matures. It was concluded that multi-rate sampling is the best method to use in sampling fluids since the liquid yield changes as a function of rate. Although bottom-hole sampling in gas condensate reservoirs may be problematic, it should always be performed to address any concerns for liquid-solid separation. Produced fluids typically reveal a specific signature that informs the operator of in situ properties. This paper presented examples that pertain to wet versus retrograde condensate behavior and the presence of an oil zone. The

  17. Modeling the Phase Composition of Gas Condensate in Pipelines

    Science.gov (United States)

    Dudin, S. M.; Zemenkov, Yu D.; Shabarov, A. B.

    2016-10-01

    Gas condensate fields demonstrate a number of thermodynamic characteristics to be considered when they are developed, as well as when gas condensate is transported and processed. A complicated phase behavior of the gas condensate system, as well as the dependence of the extracted raw materials on the phase state of the deposit other conditions being equal, is a key aspect. Therefore, when designing gas condensate lines the crucial task is to select the most appropriate methods of calculating thermophysical properties and phase equilibrium of the transported gas condensate. The paper describes a physical-mathematical model of a gas-liquid flow in the gas condensate line. It was developed based on balance equations of conservation of mass, impulse and energy of the transported medium within the framework of a quasi-1D approach. Constitutive relationships are given separately, and practical recommendations on how to apply the research results are provided as well.

  18. Gas condensate--raw material for producing liquid paraffin hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Aliyeva, R.B.; Alikishi-Zade, G.Yu.; Kuliyev, A.M.; Leonidov, A.N.; Pereverzev, A.N.

    1980-01-01

    The problem of efficient utilization of gas condensates as raw material for removal of a valuable product, liquid paraffins, is examined. A classification of gas condensates is given which is used as raw material for removing these hydrocarbons: gas condensate with high content of n-alkanes (25-40 mass percent), with average content (18-25 mass percent), with low content (12-18 mass percent), light weight fractions compositions, which do not contain fractions up to 200/sup 0/, and also, content ofless than 12% n-alkanes. Gas condensate I-III groups are 30% of the total reserve of gas condensate. Liquid paraffins hydrocarbons, produced from fractions of diesel fuel, which has been removed from Shatlyk gas condensate under conditions which simulate virtual processes of caramide deparaffinization meet all requirements without additional refining.

  19. Liquid oil production from shale gas condensate reservoirs

    Science.gov (United States)

    Sheng, James J.

    2018-04-03

    A process of producing liquid oil from shale gas condensate reservoirs and, more particularly, to increase liquid oil production by huff-n-puff in shale gas condensate reservoirs. The process includes performing a huff-n-puff gas injection mode and flowing the bottom-hole pressure lower than the dew point pressure.

  20. Importance of water Influx and waterflooding in Gas condensate reservoir

    OpenAIRE

    Ali, Faizan

    2014-01-01

    The possibility of losing valuable liquid and lower gas well deliverability have made gas condensate reservoirs very important and extra emphasizes are made to optimize hydrocarbon recovery from a gas condensate reservoir. Methods like methanol treatments, wettability alteration and hydraulic fracturing are done to restore the well deliverability by removing or by passing the condensate blockage region. The above mentioned methods are applied in the near wellbore region and only improve the w...

  1. Possibility of removing condensate and scattered oil from gas-condensate field during bed flooding

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, N.A.; Yagubov, M.S.

    1984-01-01

    The problem is set of evaluating the possible removal from the bed of scattered oil and condensate during flooding of the bed. For this purpose, an experimental study was made of the displacement by water from the porous medium of the oil and condensate saturating it. The obtained experimental results permit evaluation of the possible removal from the gas-condensate bed of scattered oil and condensate during flooding of the bed.

  2. Transport diphasique de gaz et de condensat. Aspects techniques et économiques Technical and Economic Aspects of Two-Phase Pipelining of Gas and Condensate

    Directory of Open Access Journals (Sweden)

    Bourgeois T.

    2006-11-01

    Full Text Available L'évacuation diphasique de la production d'un gisement de gaz à condensat présente des avantages importants, en particulier sur le plan économique. Les caractéristiques des écoulements diphasiques sont exposées, avec les conséquences principales sur la définition d'un schéma d'exploitation. Une comparaison économique est ensuite présentée, pour illustrer la réduction des investissements qui peut être apportée par l'évacuation diphasique de la production. Enfin, les recherches françaises sur les écoulements diphasiques dans les conduites pétrolières sont brièvement décrites, ainsi qu'un exemple de calcul sur une conduite de gaz à condensat en exploitation diphasique. The two-phase pipelining of a wet gas field production presents many advantages, especially from an economic point of view. The characteristics of two-phase flow are described, together with their main consequences on the operational scheme. Then an economic comparison is made to illustrate the reduction in investment costs that can by achieved with two-phase pipelining. Research in France on two-phase flow in gas and condensate pipelines is briefly described, and an example is given of the designing of a wet-gas pipeline currently being operated in the two-phase mode.

  3. Condensed Rotational Separation to upgrade sour gas

    NARCIS (Netherlands)

    Brouwers, J.J.H.; Kemenade, van H.P.

    2010-01-01

    A steadily increasing amount of newly located natural gas fields is severely contaminated with CO2 and/or H2S. Percentages of 30 % CO2/H2S or even larger are not uncommon. Fields with such high degrees of contaminant can not be economically exploited by conventional techniques based on amine

  4. Mn nanoparticles produced by inert gas condensation

    International Nuclear Information System (INIS)

    Ward, M B; Brydson, R; Cochrane, R F

    2006-01-01

    The results from experiments using the inert gas condensation method to produce nanoparticles of manganese are presented. Structural and compositional data have been collected through electron diffraction, EDX (energy dispersive X-ray) and EELS (electron energy loss spectroscopy). Both Mn 3 O 4 and pure Mn particles have been produced. Moisture in untreated helium gas causes the particles to oxidize, whereas running the helium through a liquid nitrogen trap removes the moisture and produces β-Mn particles in a metastable state. The particle sizes and the size distribution have been determined. Particle sizes range from 2nm to above 100 nm, however the majority of particles lie in the range below 20 nm with a modal particle size of 6 nm. As well as the modal particle size of 6 nm, there is another peak in the frequency curve at 16 nm that represents another group particles that lie in the range 12 to 20 nm. The smaller particles are single crystals, but the larger particles appear to have a dense region around their edge with a less dense centre. Determination of their exact nature is ongoing

  5. Mathematical simulation of the process of condensing natural gas

    OpenAIRE

    Tastandieva G.M.

    2015-01-01

    Presents a two-dimensional unsteady model of heat transfer in terms of condensation of natural gas at low temperatures. Performed calculations of the process heat and mass transfer of liquefied natural gas (LNG) storage tanks of cylindrical shape. The influence of model parameters on the nature of heat transfer. Defined temperature regimes eliminate evaporation by cooling liquefied natural gas. The obtained dependence of the mass flow rate of vapor condensation gas temperature. Identified the...

  6. Conditions for maximum isolation of stable condensate during separation in gas-condensate systems

    Energy Technology Data Exchange (ETDEWEB)

    Trivus, N.A.; Belkina, N.A.

    1969-02-01

    A thermodynamic analysis is made of the gas-liquid separation process in order to determine the relationship between conditions of maximum stable condensate separation and physico-chemical nature and composition of condensate. The analysis was made by considering the multicomponent gas-condensate fluid produced from Zyrya field as a ternary system, composed of methane, an intermediate component (propane and butane) and a heavy residue, C/sub 6+/. Composition of 5 ternary systems was calculated for a wide variation in separator conditions. At each separator pressure there is maximum condensate production at a certain temperature. This occurs because solubility of condensate components changes with temperature. Results of all calculations are shown graphically. The graphs show conditions of maximum stable condensate separation.

  7. The shear viscosity of a trapped Bose-condensed gas

    International Nuclear Information System (INIS)

    Shahzamanian, M.A.; Yavary, H.

    2006-01-01

    By obtaining Kubo formula type and using nonequilibrium Green's functions, we calculate the shear viscosity of a trapped Bose-condensed gas below and above the Bose-Einstein condensation temperature (T BEC ). The contributions of the interactions between condensate and noncondensate atoms and between noncondensate atoms take into account to the viscous relaxation time, by evaluating second order self-energies in Beliaev approximation

  8. Sensitivity analysis and economic optimization studies of inverted five-spot gas cycling in gas condensate reservoir

    OpenAIRE

    Shams Bilal; Yao Jun; Zhang Kai; Zhang Lei

    2017-01-01

    Gas condensate reservoirs usually exhibit complex flow behaviors because of propagation response of pressure drop from the wellbore into the reservoir. When reservoir pressure drops below the dew point in two phase flow of gas and condensate, the accumulation of large condensate amount occurs in the gas condensate reservoirs. Usually, the saturation of condensate accumulation in volumetric gas condensate reservoirs is lower than the critical condensate saturation that causes trapping of large...

  9. Condensation of an ideal gas obeying non-Abelian statistics.

    Science.gov (United States)

    Mirza, Behrouz; Mohammadzadeh, Hosein

    2011-09-01

    We consider the thermodynamic geometry of an ideal non-Abelian gas. We show that, for a certain value of the fractional parameter and at the relevant maximum value of fugacity, the thermodynamic curvature has a singular point. This indicates a condensation such as Bose-Einstein condensation for non-Abelian statistics and we work out the phase transition temperature in various dimensions.

  10. Mathematical simulation of the process of condensing natural gas

    Science.gov (United States)

    Tastandieva, G. M.

    2015-01-01

    Presents a two-dimensional unsteady model of heat transfer in terms of condensation of natural gas at low temperatures. Performed calculations of the process heat and mass transfer of liquefied natural gas (LNG) storage tanks of cylindrical shape. The influence of model parameters on the nature of heat transfer. Defined temperature regimes eliminate evaporation by cooling liquefied natural gas. The obtained dependence of the mass flow rate of vapor condensation gas temperature. Identified the possibility of regulating the process of "cooling down" liquefied natural gas in terms of its partial evaporation with low cost energy.

  11. Mathematical simulation of the process of condensing natural gas

    Directory of Open Access Journals (Sweden)

    Tastandieva G.M.

    2015-01-01

    Full Text Available Presents a two-dimensional unsteady model of heat transfer in terms of condensation of natural gas at low temperatures. Performed calculations of the process heat and mass transfer of liquefied natural gas (LNG storage tanks of cylindrical shape. The influence of model parameters on the nature of heat transfer. Defined temperature regimes eliminate evaporation by cooling liquefied natural gas. The obtained dependence of the mass flow rate of vapor condensation gas temperature. Identified the possibility of regulating the process of “cooling down” liquefied natural gas in terms of its partial evaporation with low cost energy.

  12. Hysteresis phenomenon during operation of gas condensate fields

    Energy Technology Data Exchange (ETDEWEB)

    Sadykh-Zade, E S; Karakashev, V K; Ismailov, D Kh

    1966-01-01

    Hysteresis behavior of gas-condensate mixtures was studied with a PVT apparatus. The study was conducted at 26 and 80/sup 0/C, with recombined samples having gas factors of 3,000, 6,500, and 10,000 cu meters per ton. Pressure on samples was decreased or increased at rates of 0.2; 0.1; 0.05; and 0.025 atm per sec. Composition of gas- condensate is given. It is reported that different amounts of liquid were produced by condensation and evaporation processes, i.e., results depended on whether pressure was being increased or decreased. It is suggested that the effect of hysteresis should be considered in operation of gas-condensate fields.

  13. Compositional simulations of producing oil-gas ratio behaviour in low permeable gas condensate reservoir

    OpenAIRE

    Gundersen, Pål Lee

    2013-01-01

    Master's thesis in Petroleum engineering Gas condensate flow behaviour below the dew point in low permeable formations can make accurate fluid sampling a difficult challenge. The objective of this study was to investigate the producing oil-gas ratio behaviour in the infinite-acting period for a low permeable gas condensate reservoir. Compositional isothermal flow simulations were performed using a single-layer, radial and two-dimensional, gas condensate reservoir model with low permeabili...

  14. Evaporation and condensation heat transfer with a noncondensable gas present

    International Nuclear Information System (INIS)

    Murase, M.; Kataoka, Y.; Fujii, T.

    1993-01-01

    To evaluate the system pressure of an external water wall type containment vessel, which is one of the passive systems for containment cooling, the evaporation and condensation behavior under a noncondensable gas presence has been experimentally examined. In the system, steam evaporated from the suppression pool surface into the wetwell, filled with noncondensable gas, and condensed on the containment vessel wall. The system pressure was the sum of the noncondensable gas pressure and saturated steam pressure in the wetwell. The wetwell temperature was, however, lower than the suppression pool temperature and depended on the thermal resistance on the suppression pool surface. The evaporation and condensation heat transfer coefficients in the presence of air as noncondensable gas were measured and expressed by functions of steam/air mass ratio. The evaporation heat transfer coefficients were one order higher than the condensation heat transfer coefficients because the local noncondensable gas pressure was much lower on the evaporating pool surface than on the condensing liquid surface. Using logal properties of the heat transfer surfaces, there was a similar trend between evaporation and condensation even with a noncondensable gas present. (orig.)

  15. Disposal of aqueous condensate from high efficiency gas boilers

    Energy Technology Data Exchange (ETDEWEB)

    Hardwick, G J; Pattison, J R

    1984-01-01

    If highly efficient gas-fired condensing heating appliances are installed in Britain, the aqueous condensate produced can be conveniently run into existing sewage drains. The part of the drainage system that is most vulnerable to corrosion from the mildly acid condensate is that portion adjacent to the domestic premises. The tests described indicate that this is not at risk and the only precaution that might be considered necessary is to avoid running the condensate over galvanized drain covers in order to prevent unsightly staining. Water authorities in Britain and detailed studies in the US and Holland confirm that the condensate - after dilution by domestic waste, sewage, and rainwater - would be harmless to municipal sewage systems and would not, either in volume or chemical composition, affect the working of existing sewage treatment plants.

  16. Sensitivity analysis and economic optimization studies of inverted five-spot gas cycling in gas condensate reservoir

    Directory of Open Access Journals (Sweden)

    Shams Bilal

    2017-08-01

    Full Text Available Gas condensate reservoirs usually exhibit complex flow behaviors because of propagation response of pressure drop from the wellbore into the reservoir. When reservoir pressure drops below the dew point in two phase flow of gas and condensate, the accumulation of large condensate amount occurs in the gas condensate reservoirs. Usually, the saturation of condensate accumulation in volumetric gas condensate reservoirs is lower than the critical condensate saturation that causes trapping of large amount of condensate in reservoir pores. Trapped condensate often is lost due to condensate accumulation-condensate blockage courtesy of high molecular weight, heavy condensate residue. Recovering lost condensate most economically and optimally has always been a challenging goal. Thus, gas cycling is applied to alleviate such a drastic loss in resources.

  17. Evaporation and Condensation Flows of a Vapor-Gas Mixture from or onto the Condensed Phase with an Internal Structure

    National Research Council Canada - National Science Library

    Onishi, Yoshimoto; Yamada, Ken

    2005-01-01

    Transient motions of a vapor-gas mixture due to the evaporation and condensation processes from or onto the plane condensed phase, with a temperature field as its internal structure, have been studied...

  18. On the Bose-Einstein condensation of an ideal gas

    International Nuclear Information System (INIS)

    Landau, L.J.; Wilde, I.F.

    1979-01-01

    A mathematically precise treatment is given of the well-known Bose-Einstein condensation of an ideal gas in the grand canonical ensemble at fixed density. The method works equally well for any of the standard boundary conditions and it is shown that the finite volume activity converges and that in three dimensions condensation occurs for Dirichlet, Neumann, periodic, and repulsive walls. (orig.) 891 HJ/orig. 892 CKA

  19. Holographic techniques for condensed matter systems

    International Nuclear Information System (INIS)

    Herzog, Chistopher

    2009-01-01

    Full text. Gauge/gravity duality, a concept which emerged from string theory, holds promise for revealing the secrets of certain strongly interacting real world condensed matter systems. Historically, string theorists presented their subject as a promising framework for a quantum theory of gravity. More recently, the AdS/CFT correspondence and gauge/gravity dualities have emerged as powerful tools for using what we already know about gravity to investigate the properties of strongly interacting field theories. In this colloquium, I will survey recent developments where black holes are used to calculate the thermodynamic and transport properties of quantum critical systems, superconductors, superfluids, and fermions at unitarity. (author)

  20. Synthesis and morphology of iron-iron oxide core-shell nanoparticles produced by high pressure gas condensation

    NARCIS (Netherlands)

    Xing, Lijuan; ten Brink, Gert H.; Chen, Bin; Schmidt, Franz P.; Haberfehlner, Georg; Hofer, Ferdinand; Kooi, Bart J.; Palasantzas, Georgios

    2016-01-01

    Core-shell structured Fe nanoparticles (NPs) produced by high pressure magnetron sputtering gas condensation were studied using transmission electron microscopy (TEM) techniques, electron diffraction, electron energy-loss spectroscopy (EELS), tomographic reconstruction, and Wulff shape construction

  1. Study on biological dosimetry of premature chromosome condensation technique

    International Nuclear Information System (INIS)

    Jiang Bo

    2005-01-01

    The premature chromosome condensation technique has been applied for biological dosimetry purpose. Premature chromo-some condensation was induced by incubating unstimulated human peripheral blood lymphocytes in the presence of okadaic acid or calyculin A (a phosphatase inhibitor) which eliminated the need for fusion with mitotic cells. It is now possible to examine the early damage induced by radiation. It is simple, exact when it combines with fluorecence in situ hybridization. (authors)

  2. Stepwise Bose-Einstein Condensation in a Spinor Gas.

    Science.gov (United States)

    Frapolli, C; Zibold, T; Invernizzi, A; Jiménez-García, K; Dalibard, J; Gerbier, F

    2017-08-04

    We observe multistep condensation of sodium atoms with spin F=1, where the different Zeeman components m_{F}=0,±1 condense sequentially as the temperature decreases. The precise sequence changes drastically depending on the magnetization m_{z} and on the quadratic Zeeman energy q (QZE) in an applied magnetic field. For large QZE, the overall structure of the phase diagram is the same as for an ideal spin-1 gas, although the precise locations of the phase boundaries are significantly shifted by interactions. For small QZE, antiferromagnetic interactions qualitatively change the phase diagram with respect to the ideal case, leading, for instance, to condensation in m_{F}=±1, a phenomenon that cannot occur for an ideal gas with q>0.

  3. Flue gas condensing with heat pump; Roekgaskondensering med vaermepump

    Energy Technology Data Exchange (ETDEWEB)

    Axby, Fredrik; Pettersson, Camilla [Carl Bro Energikonsult AB, Malmoe (Sweden)

    2004-11-01

    Flue gas condensing is often both a technically and economically efficient method to increase the thermal efficiency in a plant using fuels with high moisture and/or high hydrogen content. The temperature of the return water in district heating systems in Sweden is normally 50 deg C, which gives quite high efficiency for a flue gas condenser. The flue gas after the flue gas condenser still contains energy that to some extent can be recovered by a combustion air humidifier or a heat pump. The object of this project is to technically and economically analyse flue gas condensing with heat pump. The aim is that plant owners get basic data to evaluate if a coupling between a flue gas condenser and a heat pump could be of interest for their plant. With a heat pump the district heating water can be 'sub cooled' to increase the heat recover in the flue gas condenser and thereby increase the total efficiency. The project is set up as a case study of three different plants that represent different types of technologies and sizes; Aabyverket in Oerebro, Amagerforbraending in Copenhagen and Staffanstorp district heating central. In this report a system with a partial flow through the condenser of the heat pump is studied. For each plant one case with the smallest heat pump and a total optimization regarding total efficiency and cost for investment has been calculated. In addition to the optimizations sensitivity analyzes has been done of the following parameters: Moisture in fuel; Type of heat pump; Temperature of the return water in the district heating system; and, Size of plant. The calculations shows that the total efficiency increases with about 6 % by the installation of the heat pump at a temperature of the return water in the district heating system of 50 deg C at Aabyverket. The cost for production of heat is just below 210 kr/MWh and the straight time for pay-off is 5,4 years at 250 kr/MWh in heat credit and at 300 kr/MWh in basic price for electricity. The

  4. Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Edward Levy; Harun Bilirgen; John DuPoint

    2011-03-31

    Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: (1) An expanded data base on water and acid condensation characteristics of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing high-moisture, low rank coals. (2) Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. (3) Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. (4) Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. (5) Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. (6) Condensed flue gas water treatment needs and costs. (7) Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. (8) Results of cost-benefit studies of condensing heat exchangers.

  5. Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Edward; Bilirgen, Harun; DuPont, John

    2011-03-31

    Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: • An expanded data base on water and acid condensation characteristics of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing highmoisture, low rank coals. • Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. • Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. • Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. • Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. • Condensed flue gas water treatment needs and costs. • Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. • Results of cost-benefit studies of condensing heat exchangers.

  6. Sensitivity analysis and economic optimization studies of inverted five-spot gas cycling in gas condensate reservoir

    Science.gov (United States)

    Shams, Bilal; Yao, Jun; Zhang, Kai; Zhang, Lei

    2017-08-01

    Gas condensate reservoirs usually exhibit complex flow behaviors because of propagation response of pressure drop from the wellbore into the reservoir. When reservoir pressure drops below the dew point in two phase flow of gas and condensate, the accumulation of large condensate amount occurs in the gas condensate reservoirs. Usually, the saturation of condensate accumulation in volumetric gas condensate reservoirs is lower than the critical condensate saturation that causes trapping of large amount of condensate in reservoir pores. Trapped condensate often is lost due to condensate accumulation-condensate blockage courtesy of high molecular weight, heavy condensate residue. Recovering lost condensate most economically and optimally has always been a challenging goal. Thus, gas cycling is applied to alleviate such a drastic loss in resources. In gas injection, the flooding pattern, injection timing and injection duration are key parameters to study an efficient EOR scenario in order to recover lost condensate. This work contains sensitivity analysis on different parameters to generate an accurate investigation about the effects on performance of different injection scenarios in homogeneous gas condensate system. In this paper, starting time of gas cycling and injection period are the parameters used to influence condensate recovery of a five-spot well pattern which has an injection pressure constraint of 3000 psi and production wells are constraint at 500 psi min. BHP. Starting injection times of 1 month, 4 months and 9 months after natural depletion areapplied in the first study. The second study is conducted by varying injection duration. Three durations are selected: 100 days, 400 days and 900 days. In miscible gas injection, miscibility and vaporization of condensate by injected gas is more efficient mechanism for condensate recovery. From this study, it is proven that the application of gas cycling on five-spot well pattern greatly enhances condensate recovery

  7. Gas adsorption and capillary condensation in nanoporous alumina films

    Energy Technology Data Exchange (ETDEWEB)

    Casanova, Felix; Chiang, Casey E; Li, Chang-Peng; Roshchin, Igor V; Schuller, Ivan K [Physics Department, University of California-San Diego, La Jolla, CA 92093 (United States); Ruminski, Anne M; Sailor, Michael J [Department of Chemistry and Biochemistry, University of California-San Diego, La Jolla, CA 92093 (United States)], E-mail: casanova@physics.ucsd.edu

    2008-08-06

    Gas adsorption and capillary condensation of organic vapors are studied by optical interferometry, using anodized nanoporous alumina films with controlled geometry (cylindrical pores with diameters in the range of 10-60 nm). The optical response of the film is optimized with respect to the geometric parameters of the pores, for potential performance as a gas sensor device. The average thickness of the adsorbed film at low relative pressures is not affected by the pore size. Capillary evaporation of the liquid from the nanopores occurs at the liquid-vapor equilibrium described by the classical Kelvin equation with a hemispherical meniscus. Due to the almost complete wetting, we can quantitatively describe the condensation for isopropanol using the Cohan model with a cylindrical meniscus in the Kelvin equation. This model describes the observed hysteresis and allows us to use the adsorption branch of the isotherm to calculate the pore size distribution of the sample in good agreement with independent structural measurements. The condensation for toluene lacks reproducibility due to incomplete surface wetting. This exemplifies the relevant role of the fluid-solid (van der Waals) interactions in the hysteretic behavior of capillary condensation.

  8. Gas adsorption and capillary condensation in nanoporous alumina films

    International Nuclear Information System (INIS)

    Casanova, Felix; Chiang, Casey E; Li, Chang-Peng; Roshchin, Igor V; Schuller, Ivan K; Ruminski, Anne M; Sailor, Michael J

    2008-01-01

    Gas adsorption and capillary condensation of organic vapors are studied by optical interferometry, using anodized nanoporous alumina films with controlled geometry (cylindrical pores with diameters in the range of 10-60 nm). The optical response of the film is optimized with respect to the geometric parameters of the pores, for potential performance as a gas sensor device. The average thickness of the adsorbed film at low relative pressures is not affected by the pore size. Capillary evaporation of the liquid from the nanopores occurs at the liquid-vapor equilibrium described by the classical Kelvin equation with a hemispherical meniscus. Due to the almost complete wetting, we can quantitatively describe the condensation for isopropanol using the Cohan model with a cylindrical meniscus in the Kelvin equation. This model describes the observed hysteresis and allows us to use the adsorption branch of the isotherm to calculate the pore size distribution of the sample in good agreement with independent structural measurements. The condensation for toluene lacks reproducibility due to incomplete surface wetting. This exemplifies the relevant role of the fluid-solid (van der Waals) interactions in the hysteretic behavior of capillary condensation

  9. Gas adsorption and capillary condensation in nanoporous alumina films.

    Science.gov (United States)

    Casanova, Fèlix; Chiang, Casey E; Li, Chang-Peng; Roshchin, Igor V; Ruminski, Anne M; Sailor, Michael J; Schuller, Ivan K

    2008-08-06

    Gas adsorption and capillary condensation of organic vapors are studied by optical interferometry, using anodized nanoporous alumina films with controlled geometry (cylindrical pores with diameters in the range of 10-60 nm). The optical response of the film is optimized with respect to the geometric parameters of the pores, for potential performance as a gas sensor device. The average thickness of the adsorbed film at low relative pressures is not affected by the pore size. Capillary evaporation of the liquid from the nanopores occurs at the liquid-vapor equilibrium described by the classical Kelvin equation with a hemispherical meniscus. Due to the almost complete wetting, we can quantitatively describe the condensation for isopropanol using the Cohan model with a cylindrical meniscus in the Kelvin equation. This model describes the observed hysteresis and allows us to use the adsorption branch of the isotherm to calculate the pore size distribution of the sample in good agreement with independent structural measurements. The condensation for toluene lacks reproducibility due to incomplete surface wetting. This exemplifies the relevant role of the fluid-solid (van der Waals) interactions in the hysteretic behavior of capillary condensation.

  10. The effect of non-condensable gas on direct contact condensation of steam/air mixture

    International Nuclear Information System (INIS)

    Lee, H. C.; Park, S. K.; Kim, M. H.

    1998-01-01

    To investigate the effects of noncondensable gas on the direct contact film condensation of vapor mixture, a series of experiments has been carried out. The rectangular duct inclined 87.deg. to the horizontal plane was used for this experiment. The average heat transfer coefficient of the steam-air mixture was obtained at the atmospheric pressure with four main parameters, air-mass fraction, vapor velocity, film Reynolds number,and the degree of water film subcooling having an influence on the condensation heat transfer coefficient. With the analysis on 88 cases of experiments, a correlation of the average Nusselt number for direct contact film condensation of steam-air mixture at a vertical wall proposed as functions of film Reynolds number, mixture Reynolds number, air mass fraction, and Jacob number. The average heat transfer coefficient for steam-air mixture condensation decreased significantly while air mass fraction increases with the same inlet mixture velocity and inlet film temperature. The average heat transfer coefficients also decreased with the degree of film subcooling increasing and were scarcely affected by film Reynolds number below the mixture Reynolds number about 30,000

  11. Numerical modeling of condensation from vapor-gas mixtures for forced down flow inside a tube

    International Nuclear Information System (INIS)

    Yuann, R.Y.; Schrock, V.E.; Chen, Xiang, M.

    1995-01-01

    Laminar film condensation is the dominant heat transfer mode inside tubes. In the present paper direct numerical simulation of the detailed transport process within the steam-gas core flow and in the condensate film is carried out. The problem was posed as an axisymmetric two dimensional (r, z) gas phase inside an annular condensate film flow with an assumed smooth interface. The fundamental conservation equations were written for mass, momentum, species concentration and energy in the gaseous phase with effective diffusion parameters characterizing the turbulent region. The low Reynolds number two equation κ-ε model was employed to determine the eddy diffusion coefficients. The liquid film was described by similar formulation without the gas species equation. An empirical correlation was employed to correct for the effect of film waviness on the interfacial shear. A computer code named COAPIT (Condensation Analysis Program Inside Tube) was developed to implement numerical solution of the fundamental equations. The equations were solved by a marching technique working downstream from the entrance of the condensing section. COAPIT was benchmarked against experimental data and overall reasonable agreement was found for the key parameters such as heat transfer coefficient and tube inner wall temperature. The predicted axial development of radial profiles of velocity, composition and temperature and occurrence of metastable vapor add insight to the physical phenomena

  12. Numerical modeling of condensation from vapor-gas mixtures for forced down flow inside a tube

    Energy Technology Data Exchange (ETDEWEB)

    Yuann, R Y [Taiwan Power Company, Taipei (Taiwan, Province of China); Schrock, V E [Univ. of California, Berkeley, CA (United States); Chen, Xiang

    1995-09-01

    Laminar film condensation is the dominant heat transfer mode inside tubes. In the present paper direct numerical simulation of the detailed transport process within the steam-gas core flow and in the condensate film is carried out. The problem was posed as an axisymmetric two dimensional (r, z) gas phase inside an annular condensate film flow with an assumed smooth interface. The fundamental conservation equations were written for mass, momentum, species concentration and energy in the gaseous phase with effective diffusion parameters characterizing the turbulent region. The low Reynolds number two equation {kappa}-{epsilon} model was employed to determine the eddy diffusion coefficients. The liquid film was described by similar formulation without the gas species equation. An empirical correlation was employed to correct for the effect of film waviness on the interfacial shear. A computer code named COAPIT (Condensation Analysis Program Inside Tube) was developed to implement numerical solution of the fundamental equations. The equations were solved by a marching technique working downstream from the entrance of the condensing section. COAPIT was benchmarked against experimental data and overall reasonable agreement was found for the key parameters such as heat transfer coefficient and tube inner wall temperature. The predicted axial development of radial profiles of velocity, composition and temperature and occurrence of metastable vapor add insight to the physical phenomena.

  13. Bose-Einstein condensation in the relativistic ideal Bose gas.

    Science.gov (United States)

    Grether, M; de Llano, M; Baker, George A

    2007-11-16

    The Bose-Einstein condensation (BEC) critical temperature in a relativistic ideal Bose gas of identical bosons, with and without the antibosons expected to be pair-produced abundantly at sufficiently hot temperatures, is exactly calculated for all boson number densities, all boson point rest masses, and all temperatures. The Helmholtz free energy at the critical BEC temperature is lower with antibosons, thus implying that omitting antibosons always leads to the computation of a metastable state.

  14. Bose-Einstein Condensation in the Relativistic Ideal Bose Gas

    International Nuclear Information System (INIS)

    Grether, M.; Llano, M. de; Baker, George A. Jr.

    2007-01-01

    The Bose-Einstein condensation (BEC) critical temperature in a relativistic ideal Bose gas of identical bosons, with and without the antibosons expected to be pair-produced abundantly at sufficiently hot temperatures, is exactly calculated for all boson number densities, all boson point rest masses, and all temperatures. The Helmholtz free energy at the critical BEC temperature is lower with antibosons, thus implying that omitting antibosons always leads to the computation of a metastable state

  15. A case study to optimum selection of deliquification method for gas condensate well design: South Pars gas field

    Directory of Open Access Journals (Sweden)

    Ehsan Khamehchi

    2016-06-01

    Today, the most effective liquid-removal devices are pumping, the combination of liquid-diverter with gas lift and velocity string. Considering mentioned complexities, the most efficient method of liquid removal is different from one well to the others. This paper discusses a multi-criteria decision making (MCDM strategy for ranking these methods based on ELECTRE and TOPSIS techniques in a gas condensate reservoir. The most efficient model in this case, regarding its high efficiency and level of reliability is continuous gas lift. These procedures can be extended to other cases easily by changing the comparison matrix and user defined weights.

  16. Constructing a unique two-phase compressibility factor model for lean gas condensates

    Energy Technology Data Exchange (ETDEWEB)

    Moayyedi, Mahmood; Gharesheikhlou, Aliashghar [Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Azamifard, Arash; Mosaferi, Emadoddin [Amirkabir University of Technology (AUT), Tehran (Iran, Islamic Republic of)

    2015-02-15

    Generating a reliable experimental model for two-phase compressibility factor in lean gas condensate reservoirs has always been demanding, but it was neglected due to lack of required experimental data. This study presents the main results of constructing the first two-phase compressibility factor model that is completely valid for Iranian lean gas condensate reservoirs. Based on a wide range of experimental data bank for Iranian lean gas condensate reservoirs, a unique two-phase compressibility factor model was generated using design of experiments (DOE) method and neural network technique (ANN). Using DOE, a swift cubic response surface model was generated for two-phase compressibility factor as a function of some selected fluid parameters for lean gas condensate fluids. The proposed DOE and ANN models were finally validated using four new independent data series. The results showed that there is a good agreement between experimental data and the proposed models. In the end, a detailed comparison was made between the results of proposed models.

  17. Constructing a unique two-phase compressibility factor model for lean gas condensates

    International Nuclear Information System (INIS)

    Moayyedi, Mahmood; Gharesheikhlou, Aliashghar; Azamifard, Arash; Mosaferi, Emadoddin

    2015-01-01

    Generating a reliable experimental model for two-phase compressibility factor in lean gas condensate reservoirs has always been demanding, but it was neglected due to lack of required experimental data. This study presents the main results of constructing the first two-phase compressibility factor model that is completely valid for Iranian lean gas condensate reservoirs. Based on a wide range of experimental data bank for Iranian lean gas condensate reservoirs, a unique two-phase compressibility factor model was generated using design of experiments (DOE) method and neural network technique (ANN). Using DOE, a swift cubic response surface model was generated for two-phase compressibility factor as a function of some selected fluid parameters for lean gas condensate fluids. The proposed DOE and ANN models were finally validated using four new independent data series. The results showed that there is a good agreement between experimental data and the proposed models. In the end, a detailed comparison was made between the results of proposed models

  18. Field synergy characteristics in condensation heat transfer with non-condensable gas over a horizontal tube

    Directory of Open Access Journals (Sweden)

    Junxia Zhang

    2017-05-01

    Full Text Available Field synergy characteristics in condensation heat transfer with non-condensable gas (NCG over a horizontal tube were numerically simulated. Consequently, synergy angles between velocity and pressure or temperature gradient fields, gas film layer thickness, and induced velocity and shear stress on gas–liquid interface were obtained. Results show that synergy angles between velocity and temperature gradient fields are within 73.2°–88.7° and ascend slightly with the increment in mainstream velocity and that the synergy is poor. However, the synergy angle between velocity and pressure gradient fields decreases intensively with the increase in mainstream velocity at θ ≤ 30°, thereby improving the pressure loss. As NCG mass fraction increases, the gas film layer thickness enlarges and the induced velocity and shear stress on gas–liquid interface decreases. The synergy angles between velocity and temperature gradient fields increase, and the synergy angles between velocity and pressure gradient fields change at θ = 70°, decrease at θ 70°. When the horizontal tube circumference angle increases, the synergy angles between velocity and temperature or pressure gradient fields decrease, the synergy between velocity and pressure fields enhances, and the synergy between velocity and temperature fields degrades.

  19. Optimization of fracture length in gas/condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, J.; Sharma, M.M.; Pope, G.A. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Texas Univ., Austin, TX (United States)

    2006-07-01

    A common practice that improves the productivity of gas-condensate reservoirs is hydraulic fracturing. Two important variables that determine the effectiveness of hydraulic fractures are fracture length and fracture conductivity. Although there are no simple guidelines for the optimization of fracture length and the factors that affect it, it is preferable to have an optimum fracture length for a given proppant volume in order to maximize productivity. An optimization study was presented in which fracture length was estimated at wells where productivity was maximized. An analytical expression that takes into account non-Darcy flow and condensate banking was derived. This paper also reviewed the hydraulic fracturing process and discussed previous simulation studies that investigated the effects of well spacing and fracture length on well productivity in low permeability gas reservoirs. The compositional simulation study and results and discussion were also presented. The analytical expression for optimum fracture length, analytical expression with condensate dropout, and equations for the optimum fracture length with non-Darcy flow in the fracture were included in an appendix. The Computer Modeling Group's GEM simulator, an equation-of-state compositional simulator, was used in this study. It was concluded that for cases with non-Darcy flow, the optimum fracture lengths are lower than those obtained with Darcy flow. 18 refs., 5 tabs., 22 figs., 1 appendix.

  20. Condensers

    International Nuclear Information System (INIS)

    Andrieux, M.B.

    1984-01-01

    Characteristics of the condenser cooling waters of various French 900 MW nuclear power plants. Design and description of various types of condensers: condensers feeded directly with river water, condensers feeded by cooling towers, condensers feeded with sea water of brackish water. Presentation of the main problems encountered with the brass bundles (ammoniacal corrosion, erosion of the peripheral tubes, vibrations of the tubes), with the titanium bundles, with the tubular plates, the tubes-tubular plates assemblies, the coatings of the condenser water chamber (sea water), the vapor by-pass and with the air inlet. Analysis of the in service performances such as condensation pressure, oxygen content and availability [fr

  1. Condensation in gas transmission pipelines. Phase behavior of mixtures of hydrogen with natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Schouten, J.A.; Michels, J.P.J. [Amsterdam Univ. (Netherlands). Van der Waals-Zeeman Inst.; Rosmalen, R.J. van [Energy, Roden (Netherlands)

    2005-05-01

    Several pressure and temperature reductions occur along gas transmission lines. Since the pressure and temperature conditions of the natural gas in the pipeline are often close to the dew point curve, liquid dropout can occur. Injection of hydrogen into the natural gas will change the phase envelope and thus the liquid dropout. This condensation of the heavy hydrocarbons requires continuous operational attention and a positive effect of hydrogen may affect the decision to introduce hydrogen. In this paper we report on calculations of the amount of condensate in a natural gas and in this natural gas mixed with 16.7% hydrogen. These calculations have been performed at conditions prevailing in gas transport lines. The results will be used to discuss the difference in liquid dropout in a natural gas and in a mixture with hydrogen at pressure reduction stations, at crossings under waterways, at side-branching, and at separators in the pipelines. (author)

  2. The pyrolysis of gas condensate at the Shatlyk field

    Energy Technology Data Exchange (ETDEWEB)

    Magaril, R.Z.; Khankuliyev, K.; Kul' zhayev, B.A.; Sergiyenko, S.R.

    1984-01-01

    The continuing growth in industrial demand for lower olefins for the manufacture of polymer materials has necessitated an expansion in the manufacture of ethylene. Gas condensate may serve as a source of ethylene manufacturing. The influence of the contact temperature and time in the pyrolysis of unseparated condensate from the Shatlyk field on the yield of lower olefins was investigated. It was discovered that the total yield of lower olefins (C2-C4) increases with an increase in the pyrolysis temperature, reaching a maximum of 63 to 67 percent by weight at a temperature of 1098 degrees Kelvin and contact time of .5 to .7 seconds, and at 1123 degrees Kelvin and .3 seconds, the maximum ethylene yield (40 percent) was obtained at 1123 degrees Kelvin, and at all previously noted temperatures with a contact time of .9 seconds.

  3. A new algorithm predicts pressure and temperature profiles of gas/gas-condensate transmission pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Mokhatab, Saied [OIEC - Oil Industries' Engineering and Construction Group, Tehran (Iran, Islamic Republic of); Vatani, Ali [University of Tehran (Iran, Islamic Republic of)

    2003-07-01

    The main objective of the present study has been the development of a relatively simple analytical algorithm for predicting flow temperature and pressure profiles along the two-phase, gas/gas-condensate transmission pipelines. Results demonstrate the ability of the method to predict reasonably accurate pressure gradient and temperature gradient profiles under operating conditions. (author)

  4. The smoke ion source: A device for the generation of cluster ions via inert gas condensation

    International Nuclear Information System (INIS)

    McHugh, K.M.; Sarkas, H.W.; Eaton, J.G.; Bowen, K.H.; Westgate, C.R.

    1989-01-01

    We report the development of an ion source for generating intense, continuous beams of both positive and negative cluster ions. This device is the result of the marriage of the inert gas condensation method with techniques for injecting electrons directly into expanding jets. In the preliminary studies described here, we have observed cluster ion size distributions ranging from n=1-400 for Pb n + and Pb n - and from n=12-5700 for Li n - . (orig.)

  5. A CFD study of wave influence on film steam condensation in the presence of non-condensable gas

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xianmao, E-mail: xm-wang11@mails.tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Chang, Huajian, E-mail: changhj@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Corradini, Michael, E-mail: corradini@engr.wisc.edu [Department of Engineering Physics, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, WI 53706 (United States)

    2016-08-15

    Highlights: • A condensation model is incorporated in the ANSYS FLUENT. • Different turbulence models are evaluated for flows over wavy surfaces. • Wavy surfaces with and without moving velocities are used to model the wave. • Various wavy surfaces with different wave heights and wavelengths are selected. • Wave influence on film steam condensation is investigated. - Abstract: Steam condensation plays an important role in removing heat from the containment of a nuclear plant during postulated accidents. However, due to the presence of non-condensable gases such as air and hydrogen in the containment, the condensation rate can decrease dramatically. Under certain conditions, the condensate film on the cold containment walls can affect the overall heat transfer rate. The wavy interface of the condensate film is a factor and is usually believed to enhance the condensation rate, since the waves can both increase the interfacial area and disturb the non-condensable gas boundary layer. However, it is not clear how to properly account for this factor and what is its quantitative influence in experiments. In this work, a CFD approach is applied to study the wave effects on film condensation in the presence of non-condensable gas. Wavy surfaces with and without moving velocities are used to replace the wavy interface of the falling film. A condensation model is incorporated in the ANSYS FLUENT simulation and a realizable k–ε turbulence model is applied. Various wavy surfaces with different wave heights and wavelengths are selected to conduct numerical experiments with a wide range of gas velocities. The results show that the wave structure can enhance condensation rate up to ten percent mainly due to the alteration of local flow structures in the gas phase. The increments of the condensation rate due to the wavy interface can vary with different gas velocities. The investigation shows that a multiplication factor accounts for the wave effects on film

  6. Experimental and Computational Techniques in Soft Condensed Matter Physics

    Science.gov (United States)

    Olafsen, Jeffrey

    2010-09-01

    1. Microscopy of soft materials Eric R. Weeks; 2. Computational methods to study jammed Systems Carl F. Schrek and Corey S. O'Hern; 3. Soft random solids: particulate gels, compressed emulsions and hybrid materials Anthony D. Dinsmore; 4. Langmuir monolayers Michael Dennin; 5. Computer modeling of granular rheology Leonardo E. Silbert; 6. Rheological and microrheological measurements of soft condensed matter John R. de Bruyn and Felix K. Oppong; 7. Particle-based measurement techniques for soft matter Nicholas T. Ouellette; 8. Cellular automata models of granular flow G. William Baxter; 9. Photoelastic materials Brian Utter; 10. Image acquisition and analysis in soft condensed matter Jeffrey S. Olafsen; 11. Structure and patterns in bacterial colonies Nicholas C. Darnton.

  7. Materials in flue gas condensation plants; Materialval vid roekgaskondensering

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, Barbara; Nordling Magnus

    2003-02-01

    This project is the first part of a larger project. In the part reported here, materials for flue gas condensers have been investigated by contact with plant owners and suppliers and by a literature review of reported failures. If it is decided to continue with another part of the project, a number of materials will be long term tested on site. The project is complementary to an earlier project, which investigated the operating experiences from flue gas condensers in biomass fired cogeneration plants. In the project materials (steel and polymeric) suitable for long term testing in existing plants are discussed. It is proposed that testing in the second part of the project is made with material coupons in one plant fired with only biomass and one plant where biomass is co fired with other fuels. In the biomass fired plant a number of steel materials should be tested. In the co fired plant, with its harsher operating conditions, the same steel materials plus a number of polymeric materials should be tested. Materials suitable for testing are summarised in the report.

  8. Synthesis of Fe Nanoparticles Functionalized with Oleic Acid Synthesized by Inert Gas Condensation

    Directory of Open Access Journals (Sweden)

    L. G. Silva

    2014-01-01

    Full Text Available In this work, we study the synthesis of monodispersed Fe nanoparticles (Fe-NPs in situ functionalized with oleic acid. The nanoparticles were self-assembled by inert gas condensation (IGC technique by using magnetron-sputtering process. Structural characterization of Fe-NPs was performed by transmission electron microscopy (TEM. Particle size control was carried out through the following parameters: (i condensation zone length, (ii magnetron power, and (iii gas flow (Ar and He. Typically the nanoparticles generated by IGC showed diameters which ranged from ~0.7 to 20 nm. Mass spectroscopy of Fe-NPs in the deposition system allowed the study of in situ nanoparticle formation, through a quadrupole mass filter (QMF that one can use together with a mass filter. When the deposition system works without quadrupole mass filter, the particle diameter distribution is around +/−20%. When the quadrupole is in line, then the distribution can be reduced to around +/−2%.

  9. Economics of Condensing Gas Furnaces and Water Heaters Potential in Residential Single Family Homes

    OpenAIRE

    Lekov, Alex

    2010-01-01

    Residential space and water heating accounts for over 90percent of total residential primary gas consumption in the United States. Condensing space and water heating equipment are 10-30percent more energy-efficient than conventional space and water heating. Currently, condensing gas furnaces represent 40 percent of shipments and are common in the Northern U.S. market. Meanwhile, manufacturers are planning to develop condensing gas storage water heaters to qualify for Energy Star? certificati...

  10. On the design of residential condensing gas boilers

    Energy Technology Data Exchange (ETDEWEB)

    Naeslund, M.

    1997-02-01

    Two main topics are dealt with in this thesis. Firstly, the performance of condensing boilers with finned tube heat exchangers and premix burners is evaluated. Secondly, ways of avoiding condensate formation in the flue system are evaluated. In the first investigation, a transient heat transfer approach is used to predict performance of different boiler configurations connected to different heating systems. The smallest efficiency difference between heat loads and heating systems is obtained when the heat exchanger gives a small temperature difference between flue gases and return water, the heat transfer coefficient is low and the thermostat hysteresis is large. Taking into account heat exchanger size, the best boiler is one with higher heat transfer per unit area which only causes a small efficiency loss. The total heating cost at part load, including gas and electricity, has a maximum at the lowest simulated heat load. The heat supplied by the circulation heat pump is responsible for this. The second investigation evaluates methods of drying the flue gases. Reheating the flue gases in different ways and water removal in an adsorbent bed are evaluated. Reheating is tested in two specially designed boilers. The necessary reheating is calculated to approximately 100-150 deg C if an uninsulated masonry chimney is used. The tested boilers show that it is possible to design a proper boiler. The losses, stand-by and convective/radiative, must be kept at a minimum in order to obtain a high efficiency. 86 refs, 70 figs, 16 tabs

  11. Control systems for condensing flue-gas coolers related to natural-gas-fired heating plants

    International Nuclear Information System (INIS)

    Krighaar, M.; Paulsen, O.

    1992-01-01

    A theoretical study is made of the enthalpy-efficiency for a water-cooled heat exchanger added to a natural gas-fired boiler. Under varying conditions of both water flow and temperature and flue-gas flow and temperature, both in condensing and non-condensing mode, the efficiency seems to be constant. The result is very useful for comparison between two different working conditions. The efficiency is used to calculate the savings achieved for a district heating plant by using a heat exchanger. The energy economic calculations are also helpful for estimating the most appropriate size of heat exchanger. The annual savings are calculated by means of data regarding heat production, flue gas temperature and water return temperature. The savings achieved by using different connection principles such as bypass, reheating and controlled water temperature are also calculated. (author)

  12. A Simple Approach to Dynamic Material Balance in Gas-Condensate Reservoirs

    Directory of Open Access Journals (Sweden)

    Heidari Sureshjani M.

    2013-02-01

    Full Text Available In traditional material balance calculations, shut-in well pressure data are used to determine average reservoir pressure while recent techniques do not require the well to be shut-in and use instead flowing well pressure-rate data. These methods, which are known as “dynamic” material balance, are developed for single-phase flow (oil or gas in reservoirs. However, utilization of such methods for gas-condensate reservoirs may create significant errors in prediction of average reservoir pressure due to violation of the single-phase assumption in such reservoirs. In a previous work, a method for production data analysis in gas-condensate reservoirs was developed. The method required standard gas production rate, producing gas-oil ratio, flowing well pressure, CVD data and relative permeability curves. This paper presents a new technique which does not need relative permeability curves and flowing well pressure. In this method, the producing oil-gas ratio is interpolated in the vaporized oil in gas phase (Rv versus pressure (p data in the CVD table and the corresponding pressure is located. The parameter pressure/two-phase deviation factor (p/ztp is then evaluated at the determined pressure points and is plotted versus produced moles (np which forms a straight line. The nature of this plot is such that its extrapolation to point where p/ztp = 0 will give initial moles in place. Putting initial pressure/initial two-phase deviation factor (pi/ztp,i (known parameter and estimated initial moles (ni into the material balance equation, average reservoir pressure can be determined. A main assumption behind the method is that the region where both gas and condensate phases are mobile is of negligible size compared to the reservoir. The approach is quite simple and calculations are much easier than the previous work. It provides a practical engineering tool for industry studies as it requires data which are generally available in normal production

  13. Study on condensation of biomass pyrolysis gas by spray bio-oil droplets

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Kun; Cheng, Wen-Long [University of Science and Technology of China (China)], email: wlcheng@ustc.edu.cn; Chen, Jing [Anhui Electric Power Design Institute (China); Shi, Wen-Jing [Anhui Heli Co., Ltd (China)

    2011-07-01

    This is a study of bio-oil generated by fast pyrolysis; a biomass feedstock is heated to pyrolyze at a rapid rate, the gas pyrolyzed is then condensed rapidly. The interesting result is a potential alternative fuel oil. An analysis was made of the effects of the initial pyrolysis gas temperatures, the initial bio-oil droplets temperatures and diameters, and the flow ratio of the gas and the liquid droplets on the heat and mass transfer between the gas and the liquid droplets. A few criterion equations were achieved with respect to the spray condenser. This paper established the gas-liquid phase equilibrium of an aqueous multi-composition system and the spray condensation model coupling heat and mass transfer. Model calculation and analysis showed that: spray condensation can effectively cool the high-temperature pyrolysis gas quickly; with gas liquid flowing, mass transfer rate reduces; and the relationship of gas and liquid flow ratio can achieve good accuracy.

  14. Advanced treatment of flue gas condensate; Avancerad rening av roekgaskondensat

    Energy Technology Data Exchange (ETDEWEB)

    Axby, Fredrik [Carl Bro Energikonsult AB, Malmoe (Sweden); Ekengren, Oesten; Bjurhem, Jan Erik [IVL Swedish Environmental Research Inst. (Sweden)

    2004-11-01

    The aim of the project is to study different techniques to recover water to the process and to reduce emission of ammonia to water and air. Membrane technology (ultra- (UF) and nanofiltration (NF) and reverse osmosis (RO)) and a stripper have been studied for ammonia separation. The use of bio-fuel in energy production is increasing. The off-gases are often condensed to increase energy yield and to decrease emissions to air. Since the concentration of nitrogen (ammonium) is high in condensates from units with SNCR for NO{sub x}-reduction (selective non-catalytic reduction) this water has to be treated further. Another aim of the project is to replace a great part of the tap water used in the process. This can be accomplished with membrane technology. Laboratory tests revealed a certain degree of membrane fouling. However, both NF and RO worked well in the full-scale unit, in spite of problems in the condensate treatment that resulted in tar products in the water. There was no obvious negative effect on these membranes. Analyses of PAH have shown a low base concentration that may lead to fouling after a long time. UF removes most of these PAH and thus protects the following NF- or RO-membranes. NF gave about 3 times higher filtration capacity (flux) than RO for the condensate at 30 bars. This can save a lot of money, since the membrane area can be reduced to a third. High temperature also increases the flux. The results are of high interest but ought to be certified during long run tests. Fouling was low in both NF and RO, and initial flux was retained after cleaning. The reason is probably the good pre-treatment (UF). The concentration could proceed very far, which make it possibly to reuse the concentrate to the system. Simulations of an ammonia stripper showed some parameters to be critical in certain ranges, while others didn't affect the result. Airflow is a critical parameter during stable conditions within the design data. Simulated data were verified

  15. Study of condensate composition during field processing of gas of the Shatlyk field

    Energy Technology Data Exchange (ETDEWEB)

    Kuldzhayev, B.A.; Annamukhamedov, M.B.; Makarov, V.V.; Serbnenko, S.R.; Talalayev, Ye.I.

    1983-01-01

    Studies were made of the composition and properties of condensates from field separators of the East Shatlyk field. The expediency is shown of separate collection of the condensates into a separate container and used for local needs as the diesel fuel. The condensates from the UNTS separators are used as chemical raw material to produce the lowest olephins by pyrolysis of gas-oil fraction and normal paraffins from kerosene-gas-oil part to obtain the protein-vitamin concentrates.

  16. TRACE assessment on local condensation heat transfer in presence of non-condensable gas inside a vertical tube

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Jin; Ahn, Seung Hoon; Kim, Kap; Kim, Hho Jung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2009-07-01

    TRACE assessment was performed to investigate local condensation heat transfer coefficients in the presence of a noncondensable gas inside a vertical tube. The data obtained from pure steam and steam/nitrogen mixture condensation experiments were compared to study the effects of noncondensable nitrogen gas on the annular film condensation phenomena. The condenser tube had a small inner diameter of 13mm (about 1/2-in.) and this experiment had been performed to prove the effectiveness of the a Passive Residual Heat Removal System (PRHRS) of SMART (System-integrated Modular Advanced ReacTor), which is a small modular integral-type pressurized water reactor that is developed for the dual purposes of seawater desalination and small-scaled power generation. In the case of nitrogen presence, TRACE results show the converged results but the prediction is different from experimental data. The candidate reasons can be focused on several models, such as the film thickness calculation, surface area, and condensation heat transfer correlations, etc. In the case of pure steam condensation case, TRACE results shows large oscillations and do not converge. This should be investigated in detail to identify the reason. Until now, the oscillation in thermal hydraulic parameters results from the film thickness calculation and surface area calculation. For future works, the whole sets of the experiment will be assessed and the improvement of TRACE will be performed.

  17. TRACE assessment on local condensation heat transfer in presence of non-condensable gas inside a vertical tube

    International Nuclear Information System (INIS)

    Cho, Yong Jin; Ahn, Seung Hoon; Kim, Kap; Kim, Hho Jung

    2009-01-01

    TRACE assessment was performed to investigate local condensation heat transfer coefficients in the presence of a noncondensable gas inside a vertical tube. The data obtained from pure steam and steam/nitrogen mixture condensation experiments were compared to study the effects of noncondensable nitrogen gas on the annular film condensation phenomena. The condenser tube had a small inner diameter of 13mm (about 1/2-in.) and this experiment had been performed to prove the effectiveness of the a Passive Residual Heat Removal System (PRHRS) of SMART (System-integrated Modular Advanced ReacTor), which is a small modular integral-type pressurized water reactor that is developed for the dual purposes of seawater desalination and small-scaled power generation. In the case of nitrogen presence, TRACE results show the converged results but the prediction is different from experimental data. The candidate reasons can be focused on several models, such as the film thickness calculation, surface area, and condensation heat transfer correlations, etc. In the case of pure steam condensation case, TRACE results shows large oscillations and do not converge. This should be investigated in detail to identify the reason. Until now, the oscillation in thermal hydraulic parameters results from the film thickness calculation and surface area calculation. For future works, the whole sets of the experiment will be assessed and the improvement of TRACE will be performed

  18. Beryllium armour produced by evaporation-condensation technique

    International Nuclear Information System (INIS)

    Anisimov, A.; Frolov, V.; Moszherin, S.; Pepekin, G.; Pirogov, A.; Komarov, V.; Mazul, I.

    1997-01-01

    Beryllium, as armour material for ITER plasma facing components, has a limited erosion lifetime. In order to repair the surface of eroded tiles in-situ, Be-deposition technologies are under consideration. One of them uses the physical vapour deposition of beryllium on copper or beryllium substrate produced by a hot Be-target placed in the vicinity of this substrate. Three different options for using this technology for ITER Be-armour application are considered. The first option is the repair in-situ of eroded Be-tiles. The second option suggests the use of this technology to provide the joining of Be to Cu-substrate. The third option assumes the use of evaporated-condensed beryllium as a bulk tile material bonded to copper substrate by conventional joining (Brazing et al.) techniques. The first results and prospects of these approaches are presented below. (orig.)

  19. Molecular simulation of steady-state evaporation and condensation in the presence of a non-condensable gas

    Science.gov (United States)

    Liang, Zhi; Keblinski, Pawel

    2018-02-01

    Using molecular dynamics simulations, we study evaporation and condensation of fluid Ar in the presence of a non-condensable Ne gas in a nanochannel. The evaporation and condensation are driven by the temperature difference, ΔTL, between the evaporating and condensing liquid surfaces. The steady-state evaporation and condensation fluxes (JMD) are also affected by the Ne concentration, ρNe, and the nanochannel length. We find that across a wide range of ΔTL and ρNe, JMD is in good agreement with the prediction from Stefan's law and from Schrage relationships. Furthermore, for ΔTL less than ˜20% of the absolute average temperature, we find that both steady-state heat and mass fluxes are proportional to ΔTL. This allows us to determine the interfacial resistance to the heat and mass transfer and compare it with the corresponding resistances in the gas phase. In this context, we derive an analytical expression for the effective thermal conductivity of the gas region in the nanochannel and the mass transport interfacial resistance equivalent length, i.e., the length of the nanochannel for which the resistance to the mass flow is the same as the interfacial resistance to the mass flow.

  20. Measurement and calculation of gas compressibility factor for condensate gas and natural gas under pressure up to 116 MPa

    International Nuclear Information System (INIS)

    Yan, Ke-Le; Liu, Huang; Sun, Chang-Yu; Ma, Qing-Lan; Chen, Guang-Jin; Shen, De-Ji; Xiao, Xiang-Jiao; Wang, Hai-Ying

    2013-01-01

    Highlights: • Volumetric properties of two reservoir fluid samples were measured with pressure up to 116 MPa. • Dew point pressures at four temperatures for condensate gas sample are obtained. • Correlations and thermodynamic model for describing gas compressibility factor under high pressure were compared. • The thermodynamic model recommended is most suitable for fluids produced from reservoirs with a wide pressure range. -- Abstract: The volumetric properties of two reservoir fluid samples collected from one condensate gas well and one natural gas well were measured under four groups of temperatures, respectively, with pressure up to 116 MPa. For the two samples examined, the experimental results show that the gas compressibility factor increases with the increase of pressure. But the influence of the temperature is related to the range of the experimental pressure. It approximately decreases with the increase of temperature when the pressure is larger than (45 to 50) MPa, while there is the opposite trend when the pressure is lower than (45 to 50) MPa. The dew point pressure was also determined for the condensate gas sample, which decreases with the increase of temperature. The capabilities of four empirical correlations and a thermodynamic model based on equation of state for describing gas compressibility factor of reservoir fluids under high pressure were investigated. The comparison results show that the thermodynamic model recommended is the most suitable for fluids whatever produced from high-pressure reservoirs or conventional mild-pressure reservoirs

  1. Non-condensible gas fraction predictions using wet and dry bulb temperature measurements

    International Nuclear Information System (INIS)

    Bowman, J.; Griffith, P.

    1983-03-01

    A technique is presented whereby non-condensible gas mass fractions in a closed system can be determined using wet bulb and dry bulb temperature and system pressure measurements. This technique would have application in situations where sampling techniques could not be used. Using an energy balance about the wet bulb wick, and expression is obtained which relates the vapor concentration difference between the wet bulb wick and the free stream to the wet and dry bulb temperature difference and a heat to mass transfer coefficient ratio. This coefficient ratio was examined for forced and natural convection flows. This analysis was verified with forced and natural convection tests over the range of pressure and temperature from 50 to 557 psig and 415 to 576 0 F. All the data could best be fit by the natural convection analysis. This is useful when no information about the flow field is known

  2. Effects of non-condensable gas on the condensation of steam

    International Nuclear Information System (INIS)

    Jackson, J.D.; An, P.; Reinert, A.; Ahmadinejad, M.

    2000-01-01

    The experimental work reported here was undertaken with the aim of extending the database currently available on the condensation of steam in the presence of non-condensable gases and thereby improving the empirical input to thermal-hydraulic codes which might be used for design and safety assessment of advanced water-cooled nuclear reactors. Heat was removed from flowing mixtures of steam and air in a test section by means of a water-cooled condensing plate. The test facility constructed for the study incorporates a degassing unit which supplies water to a boiler. This delivers steam steadily to a mixing chamber where it joins with a flow of preheated air. The mixture of steam and air is supplied to the bottom of a cylindrical test section in which it flows upwards over a double sided condensing plate which can be vertical, inclined or horizontal, The rate at which heat is removed by cooling water flowing through internal passages in the plate can de determined calorimetrically knowing the flow rate of the water and its temperature rise. After commissioning experiments had shown that reliable measurements of condensation heat transfer rate could be made using the test facility, a programme of development work followed in the course of which three different designs of condensing plate were evaluated in turn. The version eventually used in the main programme of experiments which followed was made from copper. However, its surfaces were coated with a thin layer of nickel and then with one of chromium. It was found that such a surface consistently promoted dropwise condensation and showed no signs of deterioration after lengthy periods of use. The rate of heat removal from pure steam and from mixtures of steam and air in varying proportions was measured as a function of plate sub-cooling for a variety of plate orientations. (author)

  3. Deposition of Size-Selected Cu Nanoparticles by Inert Gas Condensation

    Directory of Open Access Journals (Sweden)

    Martínez E

    2009-01-01

    Full Text Available Abstract Nanometer size-selected Cu clusters in the size range of 1–5 nm have been produced by a plasma-gas-condensation-type cluster deposition apparatus, which combines a grow-discharge sputtering with an inert gas condensation technique. With this method, by controlling the experimental conditions, it was possible to produce nanoparticles with a strict control in size. The structure and size of Cu nanoparticles were determined by mass spectroscopy and confirmed by atomic force microscopy (AFM and scanning electron transmission microscopy (STEM measurements. In order to preserve the structural and morphological properties, the energy of cluster impact was controlled; the energy of acceleration of the nanoparticles was in near values at 0.1 ev/atom for being in soft landing regime. From SEM measurements developed in STEM-HAADF mode, we found that nanoparticles are near sized to those values fixed experimentally also confirmed by AFM observations. The results are relevant, since it demonstrates that proper optimization of operation conditions can lead to desired cluster sizes as well as desired cluster size distributions. It was also demonstrated the efficiency of the method to obtain size-selected Cu clusters films, as a random stacking of nanometer-size crystallites assembly. The deposition of size-selected metal clusters represents a novel method of preparing Cu nanostructures, with high potential in optical and catalytic applications.

  4. Use of nuclear explosions to create gas condensate storage in the USSR. LLL Treaty Verification Program

    International Nuclear Information System (INIS)

    Borg, I.Y.

    1982-01-01

    The Soviet Union has described industrial use of nuclear explosions to produce underground hydrocarbon storage. To examples are in the giant Orenburg gas condensate field. There is good reason to believe that three additional cavities were created in bedded salt in the yet to be fully developed giant Astrakhan gas condensate field in the region of the lower Volga. Although contrary to usual western practice, the cavities are believed to be used to store H 2 S-rich, unstable gas condensate prior to processing in the main gas plants located tens of kilometers from the producing fields. Detonations at Orenburg and Astrakhan preceded plant construction. The use of nuclear explosions at several sites to create underground storage of highly corrosive liquid hydrocarbons suggests that the Soviets consider this time and cost effective. The possible benefits from such a plan include degasification and stabilization of the condensate before final processing, providing storage of condensate during periods of abnormally high natural gas production or during periods when condensate but not gas processing facilities are undergoing maintenance. Judging from information provided by Soviet specialists, the individual cavities have a maximum capacity on the order of 50,000 m 3

  5. Bose-Einstein condensation in an ultra-hot gas of pumped magnons.

    Science.gov (United States)

    Serga, Alexander A; Tiberkevich, Vasil S; Sandweg, Christian W; Vasyuchka, Vitaliy I; Bozhko, Dmytro A; Chumak, Andrii V; Neumann, Timo; Obry, Björn; Melkov, Gennadii A; Slavin, Andrei N; Hillebrands, Burkard

    2014-03-11

    Bose-Einstein condensation of quasi-particles such as excitons, polaritons, magnons and photons is a fascinating quantum mechanical phenomenon. Unlike the Bose-Einstein condensation of real particles (like atoms), these processes do not require low temperatures, since the high densities of low-energy quasi-particles needed for the condensate to form can be produced via external pumping. Here we demonstrate that such a pumping can create remarkably high effective temperatures in a narrow spectral region of the lowest energy states in a magnon gas, resulting in strikingly unexpected transitional dynamics of Bose-Einstein magnon condensate: the density of the condensate increases immediately after the external magnon flow is switched off and initially decreases if it is switched on again. This behaviour finds explanation in a nonlinear 'evaporative supercooling' mechanism that couples the low-energy magnons overheated by pumping with all the other thermal magnons, removing the excess heat, and allowing Bose-Einstein condensate formation.

  6. Condensation and dissociation rates for gas phase metal clusters from molecular dynamics trajectory calculations

    Science.gov (United States)

    Yang, Huan; Goudeli, Eirini; Hogan, Christopher J.

    2018-04-01

    In gas phase synthesis systems, clusters form and grow via condensation, in which a monomer binds to an existing cluster. While a hard-sphere equation is frequently used to predict the condensation rate coefficient, this equation neglects the influences of potential interactions and cluster internal energy on the condensation process. Here, we present a collision rate theory-molecular dynamics simulation approach to calculate condensation probabilities and condensation rate coefficients. We use this approach to examine atomic condensation onto 6-56-atom Au and Mg clusters. The probability of condensation depends upon the initial relative velocity (v) between atom and cluster and the initial impact parameter (b). In all cases, there is a well-defined region of b-v space where condensation is highly probable, and outside of which the condensation probability drops to zero. For Au clusters with more than 10 atoms, we find that at gas temperatures in the 300-1200 K range, the condensation rate coefficient exceeds the hard-sphere rate coefficient by a factor of 1.5-2.0. Conversely, for Au clusters with 10 or fewer atoms and for 14- and 28-atom Mg clusters, as cluster equilibration temperature increases, the condensation rate coefficient drops to values below the hard-sphere rate coefficient. Calculations also yield the self-dissociation rate coefficient, which is found to vary considerably with gas temperature. Finally, calculations results reveal that grazing (high b) atom-cluster collisions at elevated velocity (>1000 m s-1) can result in the colliding atom rebounding (bounce) from the cluster surface or binding while another atom dissociates (replacement). The presented method can be applied in developing rate equations to predict material formation and growth rates in vapor phase systems.

  7. Improvement of degradation with non-condensable gas in micro steam injector

    International Nuclear Information System (INIS)

    Saihara, Atsushi; Horiki, Sachiyo; Osakabe, Masahiro; Ohmori, Shuichi

    2007-01-01

    Effect of non-condensable gas on a micro steam injector (MSI) to obtain a vacuum was experimentally studied. When a pure steam was used in the MSI, the high vacuum condition was obtained. However when the mass fraction of air included in the steam was larger than a cartain value, the MSI became unstable and the vacuum condition could not be obtained. It is considered that the malfunction is due to the instability triggered with the uncondensed steam remained at the throat in downstream of the condensing region. The water nozzle was expected to be a key component to mitigate the effect of non-condensable gas. Three kinds of water nozzle whose flow areas were round, star and screw shapes were used in the present experiment. The star-shaped nozzle where the increased surface area could be expected to compensate the degradation of condensation failed to improve the malfunction of MSI with the non-condensable gas. The screw nozzle expected to drive air away outside the condensing surface could mitigate the effect of non-condensable gas. (author)

  8. Market diffusion, technological learning, and cost-benefit dynamics of condensing gas boilers in the Netherlands

    International Nuclear Information System (INIS)

    Weiss, Martin; Dittmar, Lars; Junginger, Martin; Patel, Martin K.; Blok, Kornelis

    2009-01-01

    High costs often prevent the market diffusion of novel and efficient energy technologies. Monitoring cost and price decline for these technologies is thus important in order to establish effective energy policy. Here, we present experience curves and cost-benefit analyses for condensing gas boilers produced and sold in the Netherlands between 1981 and 2006. For the most dominant boiler type on the Dutch market, i.e., condensing gas combi boilers, we identify learning rates of 14±1% for the average price and 16±8% for the additional price relative to non-condensing devices. Economies of scale, competitive sourcing of boiler components, and improvements in boiler assembly are among the main drivers behind the observed price decline. The net present value of condensing gas combi boilers shows an overall increasing trend. Purchasing in 2006 a gas boiler of this type instead of a non-condensing device generates a net present value of 970 EUR (Euro) and realizes CO 2 (carbon dioxide) emission savings at negative costs of -120 EUR per tonne CO 2 . We attribute two-thirds of the improvements in the cost-benefit performance of condensing gas combi boilers to technological learning and one-third to a combination of external effects and governmental policies.

  9. Natural gas and condensate occurrence in salt, specifically in the salt stock Gorleben-Rambow. Literature study

    International Nuclear Information System (INIS)

    Schneider, Ulrich

    2011-01-01

    The study on the natural gas and condensate occurrence in salt, specifically in the salt stock Gorleben-Rambow covers the topics development of salt deposits, salt stocks, crude oil and natural gas, gas and condensate inclusions in evaporite. Experimental data on crude oil borehole studies in Gorleben, natural gas drill holes in the salt stock Rambow, Luechow Z1 - saltstock Wustrow, gas indications, gas occurrences and gas detection are summarized.

  10. Effect of retrograde gas condensate in low permeability natural gas reservoir; Efeito da condensacao retrograda em reservatorios de gas natural com baixa permeabilidade

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Paulo Lee K.C. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica; Ligero, Eliana L.; Schiozer, Denis J. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Engenharia de Petroleo

    2008-07-01

    Most of Brazilian gas fields are low-permeability or tight sandstone reservoirs and some of them should be gas condensate reservoir. In this type of natural gas reservoir, part of the gaseous hydrocarbon mixture is condensate and the liquid hydrocarbon accumulates near the well bore that causes the loss of productivity. The liquid hydrocarbon formation inside the reservoir should be well understood such as the knowledge of the variables that causes the condensate formation and its importance in the natural gas production. This work had as goal to better understanding the effect of condensate accumulation near a producer well. The influence of the porosity and the absolute permeability in the gas production was studied in three distinct gas reservoirs: a dry gas reservoir and two gas condensate reservoirs. The refinement of the simulation grid near the producer well was also investigated. The choice of simulation model was shown to be very important in the simulation of gas condensate reservoirs. The porosity was the little relevance in the gas production and in the liquid hydrocarbon formation; otherwise the permeability was very relevant. (author)

  11. Effect of non-condensable gas on heat transfer in steam turbine condenser and modelling of ejector pump system by controlling the gas extraction rate through extraction tubes

    International Nuclear Information System (INIS)

    Strušnik, Dušan; Golob, Marjan; Avsec, Jurij

    2016-01-01

    Graphical abstract: Control of the amount of the pumped gases through extraction tubes. The connecting locations interconnect the extraction tubes for STC gas pumping. The extraction tubes are fitted with 3 control valves to control the amount of the pumped gas depending on the temperature of the pumped gas. The amount of the pumped gas increases through the extraction tubes, where the pumped gases are cooler and decreases, at the same time, through the extraction tubes, where the pumped gases are warmer. As a result, pumping of a larger amount of NCG is ensured and of a smaller amount of CG, given that the NCG concentration is the highest on the colder places. This way, the total amount of the pumped gases from the STC can be reduced, the SEPS operates more efficiently and consumes less energy for its operation. - Highlights: • Impact of non-condensable gas on heat transfer in a steam turbine condenser. • The ejector system is optimised by selecting a Laval nozzle diameter. • Simulation model of the control of the amount of pumped gases through extraction tubes. • Neural network and fuzzy logic systems used to control gas extraction rate. • Simulation model was designed by using real process data from the thermal power plant. - Abstract: The paper describes the impact of non-condensable gas (NCG) on heat transfer in a steam turbine condenser (STC) and modelling of the steam ejector pump system (SEPS) by controlling the gas extraction rate through extraction tubes. The ideal connection points for the NCG extraction from the STC are identified by analysing the impact of the NCG on the heat transfer and measuring the existing system at a thermal power plant in Slovenia. A simulation model is designed using the Matlab software and Simulink, Neural Net Work, Fuzzy Logic and Curve Fitting Toolboxes, to control gas extraction rate through extraction tubes of the gas pumped from the STC, thus optimising the operation of the steam ejector pump system (SEPS). The

  12. Flue gas condensation in straw fired CHP plants; Roeggaskondensation i halmfyrede kraftvarmeanlaeg

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-06-15

    The high price of straw and a general demand for increased use of straw in power and heat production are expected to result in an increased need for efficient fuel utilization. The use of flue gas condensation in straw fired CHP plants can contribute to a higher exploitation of energy, and at the same time open of the possibility of utilization of wet (cheaper) fuels without energy loss. Furthermore flue gas condensation can contribute to the flue gas cleaning process through removal of HCl and SO{sub 2} as well as in particle cleaning in wet cleaning processes. With starting point in a straw fired CHP plant the technical and economic consequences of installation of a flue gas condensation system are investigated. Fuel exploitation and power/heat production distribution is included in the investigation. (BA)

  13. Performance of casting aluminum-silicon alloy condensing heating exchanger for gas-fired boiler

    Science.gov (United States)

    Cao, Weixue; Liu, Fengguo; You, Xue-yi

    2018-01-01

    Condensing gas boilers are widely used due to their high heat efficiency, which comes from their ability to use the recoverable sensible heat and latent heat in flue gas. The condensed water of the boiler exhaust has strong corrosion effect on the heat exchanger, which restricts the further application of the condensing gas boiler. In recent years, a casting aluminum-silicon alloy (CASA), which boasts good anti-corrosion properties, has been introduced to condensing hot water boilers. In this paper, the heat transfer performance, CO and NOx emission concentrations and CASA corrosion resistance of a heat exchanger are studied by an efficiency bench test of the gas-fired boiler. The experimental results are compared with heat exchangers produced by Honeywell and Beka. The results show that the excess air coefficient has a significant effect on the heat efficiency and CO and NOx emission of the CASA water heater. When the excess air coefficient of the CASA gas boiler is 1.3, the CO and NOx emission concentration of the flue gas satisfies the design requirements, and the heat efficiency of water heater is 90.8%. In addition, with the increase of heat load rate, the heat transfer coefficient of the heat exchanger and the heat efficiency of the water heater are increased. However, when the heat load rate is at 90%, the NOx emission in the exhaust gas is the highest. Furthermore, when the temperature of flue gas is below 57 °C, the condensation of water vapor occurs, and the pH of condensed water is in the 2.5 5.5 range. The study shows that CASA water heater has good corrosion resistance and a high heat efficiency of 88%. Compared with the heat exchangers produced by Honeywell and Beka, there is still much work to do in optimizing and improving the water heater.

  14. The influence of surface-active agents in gas mixture on the intensity of jet condensation

    Science.gov (United States)

    Yezhov, YV; Okhotin, VS

    2017-11-01

    The report presents: the methodology of calculation of contact condensation of steam from the steam-gas mixture into the stream of water, taking into account: the mass flow of steam through the boundary phase, particularly the change in turbulent transport properties near the interface and their connection to the interface perturbations due to the surface tension of the mixture; the method of calculation of the surface tension at the interface water - a mixture of fluorocarbon vapor and water, based on the previously established analytical methods we calculate the surface tension for simple one - component liquid-vapor systems. The obtained analytical relation to calculate the surface tension of the mixture is a function of temperature and volume concentration of the fluorocarbon gas in the mixture and is true for all sizes of gas molecules. On the newly created experimental stand is made verification of experimental studies to determine the surface tension of pure substances: water, steam, C3F8 pair C3F8, produced the first experimental data on surface tension at the water - a mixture of water vapor and fluorocarbon C3F8. The obtained experimental data allow us to refine the values of the two constants used in the calculated model of the surface tension of the mixture. Experimental study of jet condensation was carried out with the flow in the zone of condensation of different gases. The condensation process was monitored by measurement of consumption of water flowing from the nozzle, and the formed condensate. When submitting C3F8, there was a noticeable, intensification condensation process compared with the condensation of pure water vapor. The calculation results are in satisfactory agreement with the experimental data on surface tension of the mixture and steam condensation from steam-gas mixture. Analysis of calculation results shows that the presence of surfactants in the condensation zone affects the partial vapor pressure on the interfacial surface, and

  15. Bose-Einstein condensation of a relativistic Bose gas trapped in a general external potential

    International Nuclear Information System (INIS)

    Su Guozhen; Chen Jincan; Chen Lixuan

    2006-01-01

    Bose-Einstein condensation of an ideal relativistic Bose gas trapped in a generic power-law potential is investigated. The analytical expressions for some important parameters such as the critical temperature, ground-state fraction and heat capacity are derived. The general criteria on the occurrence of Bose-Einstein condensation and the discontinuity of heat capacity at the critical temperature are obtained. The results obtained here present a unified description for the Bose-Einstein condensation of a class of ideal Bose systems so that many important conclusions in the literature are included in this paper

  16. Effect of non-condensation gas on pressure oscillation of submerged steam jet condensation

    International Nuclear Information System (INIS)

    Zhao, Quanbin; Cong, Yuelei; Wang, Yingchun; Chen, Weixiong; Chong, Daotong; Yan, Junjie

    2016-01-01

    Highlights: • Oscillation intensity of steam–air jet increases with rise of water temperature. • Oscillation intensity reduces obviously when air is mixed. • Both first and second dominant frequencies decrease with rise of air mass fraction. • Air has little effect on power of 1st & 2nd frequency bands under low temperature. • The maximum oscillation power occurs under case of A = 1% and T ⩾ 50 °C. - Abstract: The effect of air with low mass fraction on the oscillation intensity and oscillation frequency of a submerged steam jet condensation is investigated under stable condensation region. With air mixing in steam, an obvious dynamic pressure peak appears along the jet direction. The intensity peak increases monotonously with the rise of steam mass flux and water temperature. Peak position moves downstream with the rise of air mass fraction. Moreover, when compared with that of pure steam jet, the oscillation intensity clearly decreases as air is mixed. However, when water temperature is lower than approximately 45 °C, oscillation intensity increases slightly with the rise of air mass fraction, and when water temperature is higher than 55 °C, the oscillation intensity decreases greatly with the rise of air mass fraction. Both the first and second dominant frequencies decrease with rise of air mass fraction. Finally, effect of air mass fractions on the oscillation power of the first and second dominant frequency bands shows similar trends. Under low water temperature, the mixed air has little effect on the oscillation power of both first and second frequency bands. However, when water temperature is high, the oscillation power of both first and second frequency bands appears an obvious peak when air mass fraction is about 1%. With further rise of air mass fraction, the oscillation power decreases gradually.

  17. Waste heat recovery system including a mechanism for collection, detection and removal of non-condensable gas

    Science.gov (United States)

    Ernst, Timothy C.; Zigan, James A.

    2017-06-20

    The disclosure describes a non-condensable gas collection, detection, and removal system for a WHR system that helps to maintain cycle efficiency of the WHR system across the life of an engine system associated with the WHR system. A storage volume is configured to collect non-condensable gas received from the working fluid circuit, and a release valve is configured to selectively release non-condensable gas contained within the storage volume.

  18. Comparative study during condensation of R152 a and R134 a with presence of non-condensable gas inside a vertical tube

    Science.gov (United States)

    Charef, Adil; Feddaoui, M'barek; Najim, Monssif; Meftah, Hicham

    2018-04-01

    A computational study of the liquid film condensation from vapour-gas mixtures of HFC refrigerants inside a vertical tube is performed. The external wall of the tube is subjected to constant temperature. The model uses an implicit finite difference method to solve the governing equations for the liquid film and gas flow together including the boundary and interfacial matching conditions. Parametric computations were realised to examine the effects of inlet Reynolds number, tube length, and inlet temperature of the gas mixtures on the condensation mechanism. A comparative study between the results obtained for studied R152 a and R134 a with presence of non-condensable gas is made. The predicted results indicate that the condensation of R152 a-air corresponds to a higher accumulated condensation m c d and local heat transfer coefficient h T when compared to R134 a-air in the same conditions. Increasing the inlet Reynolds number or the tube length improve the condensation. Additionally, lower non-condensable gas in R152 a - a i r substantially enhances the heat and mass exchanges.

  19. New analytic and computational techniques for finite temperature condensed matter systems

    International Nuclear Information System (INIS)

    Arias, T.A.

    1992-01-01

    By employing a special summation technique we find that the breakdown of the Meissner-Ochsenfeld effect in the three dimensional Bose gas as the applied field passes;through its critical value is an entropy driven weakly first order transition, rather than the second order transition usually ascribed to the system. The transition is second order at the usual Bose condensation temperature T c as well as at T = O, with a line o first order transition connecting these critical points. The first order transitions make the Bose gas resemble familiar superconductors, and a Landau-Ginzburg analysis indicates that the Bose gas is always a type I superconductor. We employ the recently introduce conjugate-gradient methods for minimization of the electronic energy functional to perform an extensive ab initio study of the Σ = 5 tilt [310] grain boundary in germanium. We find that the boundary reliably reconstructs to the tetrahedrally bonded network observed in HREM experiments without the proliferation of false local minima observed in similar twist boundaries. The reduced density of bonds crossing the grain boundary plan leads us to conjecture that the boundary may be a preferred fracture interface. We then combine these conjugate-gradient methods with a new technique for generating trail wavefunctions to produce an efficient ab initio molecular dynamics scheme that is that is at least two orders of magnitude more accurate than previous schemes and thus allows accurate calculation of dynamic correlation functions while maintaining tolerable energy conservation for microcanonical averages of those correlation function over picosecond time scales. We present two advances which greatly enhance the efficiency of our new ab initio molecular dynamics technique. We introduce a class of generalizations of traditional Fermionic energy functionals which allow us to lift the orthonormality constraints on the single particle orbitals and thus speed convergence

  20. Experimental substantiation of combined methods for designing processes for the commercial preparation of gas at gas condensate fields

    Energy Technology Data Exchange (ETDEWEB)

    Gurevich, G R; Karlinskii, E D; Posypkina, T V

    1977-04-01

    An analysis is made of the possibility of using two analytical methods for studying vapor--liquid equilibrium of hydrocarbon mixtures that are used in designing the separation of natural gas and the stabilization of condensate--the Chao and Sider method, which uses computations by equilibrium constants. A combined computational method is proposed for describing a unified process of natural gas separation and condensate stabilization. The method of preparing the original data for the computation of the separation and stabilization processes can be significantly simplified. 10 references, 1 table.

  1. Condensation and critical exponents of an ideal non-Abelian gas

    Science.gov (United States)

    Talaei, Zahra; Mirza, Behrouz; Mohammadzadeh, Hosein

    2017-11-01

    We investigate an ideal gas obeying non-Abelian statistics and derive the expressions for some thermodynamic quantities. It is found that thermodynamic quantities are finite at the condensation point where their derivatives diverge and, near this point, they behave as \\vert T-Tc\\vert^{-ρ} in which Tc denotes the condensation temperature and ρ is a critical exponent. The critical exponents related to the heat capacity and compressibility are obtained by fitting numerical results and others are obtained using the scaling law hypothesis for a three-dimensional non-Abelian ideal gas. This set of critical exponents introduces a new universality class.

  2. Fluid flow behaviour of gas-condensate and near-miscible fluids at the pore scale

    Energy Technology Data Exchange (ETDEWEB)

    Dawe, Richard A. [Department of Chemical Engineering, University of West Indies, St. Augustine (Trinidad and Tobago); Grattoni, Carlos A. [Department of Earth Science and Engineering, Imperial College, London, SW7 2BP (United Kingdom)

    2007-02-15

    Retrograde condensate reservoir behaviour is complex with much of the detailed mechanisms of the multiphase fluid transport and mass transfer between the phases within the porous matrix still speculative. Visual modelling of selected processes occurring at the pore level under known and controlled boundary conditions can give an insight to fluid displacements at the core scale and help the interpretation of production behaviour at reservoir scale. Visualisation of the pore scale two-phase flow mechanisms has been studied experimentally at low interfacial tensions, < 0.5 mN/m, using a partially miscible fluid system in glass visual micro models. As the interfacial tension decreases the balance between fluid-fluid forces (interfacial, spreading and viscous) and fluid-solid interactions (wettability and viscous interactions) changes. Data measurements in the laboratory, particularly relative permeability, will therefore always be difficult especially for condensate fluids just below their dew point. What is certain is that gas production from a gas-condensate leads to condensate dropout when pressure falls below the dew point, either within the wellbore or, more importantly, in the reservoir. This paper illustrates some pore scale physics, particularly interfacial phenomena at low interfacial tension, which has relevance to appreciating the flow of condensate fluids close to their dew point either near the wellbore (which affects well productivity) or deep inside the reservoir (which affects condensate recovery). (author)

  3. EOS simulation and GRNN modeling of the constant volume depletion behavior of gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Elsharkawy, A.M.; Foda, S.G. [Kuwait University, Safat (Kuwait). Petroleum Engineering Dept.

    1998-03-01

    Currently, two approaches are being used to predict the changes in retrograde gas condensate composition and estimate the pressure depletion behavior of gas condensate reservoirs. The first approach uses the equation of states whereas the second uses empirical correlations. Equations of states (EOS) are poor predictive tools for complex hydrocarbon systems. The EOS needs adjustment against phase behavior data of reservoir fluid of known composition. The empirical correlation does not involve numerous numerical computations but their accuracy is limited. This study presents two general regression neural network (GRNN) models. The first model, GRNNM1, is developed to predict dew point pressure and gas compressibility at dew point using initial composition of numerous samples while the second model, GRNNM2, is developed to predict the changes in well stream effluent composition at any stages of pressure depletion. GRNNM2 can also be used to determine the initial reservoir fluid composition using dew point pressure, gas compressibility at dew point, and reservoir temperature. These models are based on analysis of 142 sample of laboratory studies of constant volume depletion (CVD) for gas condensate systems forming a total of 1082 depletion stages. The database represents a wide range of gas condensate systems obtained worldwide. The performance of the GRNN models has been compared to simulation results of the equation of state. The study shows that the proposed general regression neural network models are accurate, valid, and reliable. These models can be used to forecast CVD data needed for many reservoir engineering calculations in case laboratory data is unavailable. The GRNN models save computer time involved in EOS calculations. The study also show that once these models are properly trained they can be used to cut expenses of frequent sampling and laborious experimental CVD tests required for gas condensate reservoirs. 55 refs., 13 figs., 6 tabs.

  4. Condensation heat transfer with noncondensable gas for passive containment cooling of nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Leonardi, Tauna [Schlumberger, 14910 Airline Rd., Rosharon, TX 77583 (United States)]. E-mail: Tleonardi@slb.com; Ishii, Mamoru [School of Nuclear Engineering, Purdue University, West Lafayette, IN 47907 (United States)]. E-mail: Ishii@ecn.purdue.edu

    2006-09-15

    Noncondensable gases that come from the containment and the interaction of cladding and steam during a severe accident deteriorate a passive containment cooling system's performance by degrading the heat transfer capabilities of the condensers in passive containment cooling systems. This work contributes to the area of modeling condensation heat transfer with noncondensable gases in integral facilities. Previously existing correlations and models are for the through-flow of the mixture of steam and the noncondensable gases and this may not be applicable to passive containment cooling systems where there is no clear passage for the steam to escape. This work presents a condensation heat transfer model for the downward cocurrent flow of a steam/air mixture through a condenser tube, taking into account the atypical characteristics of the passive containment cooling system. An empirical model is developed that depends on the inlet conditions, including the mixture Reynolds number and noncondensable gas concentration.

  5. Fluid flow in gas condensate reservoirs. The interplay of forces and their relative strengths

    Energy Technology Data Exchange (ETDEWEB)

    Ursin, Jann-Rune [Stavanger University College, Department of Petroleum Engineering, PO Box 8002, Stavanger, 4068 (Norway)

    2004-02-01

    Natural production from gas condensate reservoirs is characterized by gas condensation and liquid dropout in the reservoir, first in the near wellbore volume, then as a cylindrical shaped region, dynamically developing into the reservoir volume. The effects of liquid condensation are reduced productivity and loss of production. Successful forecast of well productivity and reservoir production depends on detailed understanding of the effect of various forces acting on fluid flow in time and space. The production form gas condensate reservoirs is thus indirectly related to the interplay of fundamental forces, such as the viscosity, the capillary, the gravitational and the inertial force and their relative strengths, demonstrated by various dimensionless numbers. Dimensionless numbers are defined and calculated for all pressure and space coordinates in a test reservoir. Various regions are identified where certain forces are more important than others. Based on reservoir pressure development, liquid condensation and the numerical representation of dimensionless numbers, a conceptual understanding of a varying reservoir permeability has been reached.The material balance, the reservoir fluid flow and the wellbore flow calculations are performed on a cylindrical reservoir model. The ratios between fundamental forces are calculated and dimensionless numbers defined. The interplay of forces, demonstrated by these numbers, are calculated as function of radial dimension and reservoir pressure.

  6. State of the Art Report On Condensation Phenomena Within Tubes in the Presence of Noncondensable Gas

    International Nuclear Information System (INIS)

    Polo, J.

    1998-01-01

    Condensation phenomena play an important role in many industrial applications; in particular; the nuclear industry uses such processes in different systems for both operation and safety aspects. Thus most of the engineering safety features in the current Light Water Reactor (LWR) plants as well as in the new advanced/passive type design are based on the condensation phenomena inside tubes to reduce the system pressure and to remove the decay heat released under accidental conditions. Regarding the new advanced/passive plant designs such a systems must ensure their capabilities under severe accident conditions, that means, under the presence of non-condensable gas an even aerosol particles. The presence of even a small quantity of non condensable gas in liquid-vapour has profound influence on the resistance to heat transfer at the liquid-vapour interface leading to reduce in the heat transfer rate. In consequence, the safety analysis of the Simplified Boiling Water Reactor (SBWR) promoted in increase in the modelling, model development and experimental research on the gas mixtures condensing inside vertical tubes. This report summarises the last models developed as well as the experimental findings on such processes. (Author) 51 refs

  7. Temperature Programmed Desorption of Quench-condensed Krypton and Acetone in Air; Selective Concentration of Ultra-trace Gas Components.

    Science.gov (United States)

    Suzuki, Taku T; Sakaguchi, Isao

    2016-01-01

    Selective concentration of ultra-trace components in air-like gases has an important application in analyzing volatile organic compounds in the gas. In the present study, we examined quench-condensation of the sample gas on a ZnO substrate below 50 K followed by temperature programmed desorption (TPD) (low temperature TPD) as a selective gas concentration technique. We studied two specific gases in the normal air; krypton as an inert gas and acetone as a reactive gas. We evaluated the relationship between the operating condition of low temperature TPD and the lowest detection limit. In the case of krypton, we observed the selective concentration by exposing at 6 K followed by thermal desorption at about 60 K. On the other hand, no selectivity appeared for acetone although trace acetone was successfully concentrated. This is likely due to the solvent effect by a major component in the air, which is suggested to be water. We suggest that pre-condensation to remove the water component may improve the selectivity in the trace acetone analysis by low temperature TPD.

  8. Numerical analyses on the effect of capillary condensation on gas diffusivities in porous media

    Science.gov (United States)

    Yoshimoto, Yuta; Hori, Takuma; Kinefuchi, Ikuya; Takagi, Shu

    2017-11-01

    We investigate the effect of capillary condensation on gas diffusivities in porous media composed of randomly packed spheres with moderate wettability. Lattice density functional theory simulations successfully reproduce realistic adsorption/desorption isotherms and provide fluid density distributions inside the porous media. We find that capillary condensations lead to the occlusion of narrow pores because they preferentially occur at confined spaces surrounded by the solid walls. Consequently, the characteristic lengths of the partially wet structures are larger than those of the corresponding dry structures with the same porosities. Subsequent gas diffusion simulations exploiting the mean-square displacement method indicate that while effective diffusion coefficients significantly decrease in the presence of partially condensed liquids, they are larger than those in the dry structures with the same porosities. Most importantly, we find that the porosity-to-tortuosity ratio, which is a crucial parameter that determines the effective diffusion coefficient, can be reasonably related to the porosity even for the partially wet porous media.

  9. Materials in flue gas condensation plants. Stage 2; Materialval vid roekgaskondensering. Etapp 2

    Energy Technology Data Exchange (ETDEWEB)

    Nordling, Magnus; Bergman, Gunnar; Baeck, Gustaf; Jacobsson, Karin; Pahverk, Helen; Roemhild, Stefanie

    2004-12-01

    The corrosion resistance of some metallic and polymeric materials has been investigated in the flue gas scrubbers/condensers in the power plants at Igelsta using waste wood and Brista using bio fuel in the boilers. The materials were exposed inside the inlet part of the condenser and inside the flue gas duct after the condenser. In Brista, the polymeric materials were also exposed to the hot flue gases inside the duct before the condenser. The temperature of the gases before and after the condenser in Brista was 140 deg C and 50-60 deg C, respectively. In Igelsta, the flue gas temperature after the condenser was 45 deg C. The metallic coupons in the condenser were located in the spray-zone, both in Igelsta and Brista. That was true also for the polymeric material in Brista. In both plants, the wash-solution had a pH of 7-8, a temperature of 30 deg C, and a low content of chloride. The metallic materials investigated were stainless steels of the following grades: 17-12-2.5, 2205, SAF2507 and 254SMO. The major part of the polymeric materials investigated consisted of FRP laminates, which were made with different combinations of resin type of surface veil and type of chopped strand mat (CSM). Laminates with a new type of vinyl ester resin, Atlac E-Nova FW 1045, a new type of a stress-corrosion-resistant glass-fibre called Arcotex, and two types of surface reinforcement of carbon fibre have been compared to laminates of common type. Laminates with a special reinforcement of the type 3-D fabric were also included as well as five polypropylene materials (PP) with varying degree of stabilisation, two glass-flake materials applied on carbon steel and a butyl rubber. The corrosion resistance of the materials was evaluated after seven a months exposure at the different positions in the plants. The stainless steel materials were evaluated with respect to uniform corrosion, pitting and crevice attack. The corrosion resistance of the polymeric materials was evaluated with

  10. Theoretical modeling of steam condensation in the presence of a noncondensable gas in horizontal tubes

    International Nuclear Information System (INIS)

    Lee, Kwon-Yeong; Kim, Moo Hwan; Kim, Moo Hwan

    2008-01-01

    A theoretical model was developed to investigate a steam condensation with a noncondensable gas in a horizontal tube. The heat transfer through the vapor/noncondensable gas mixture boundary layer consists of the sensible heat transfer and the latent heat transfer given up by the condensing vapor, and it must equal that from the condensate film to the tube wall. Therefore, the total heat transfer coefficient is given by the film, condensation and sensible heat transfer coefficients. The film heat transfer coefficients of the upper and lower portions of the tube were calculated separately from Rosson and Meyers (1965) correlation. The heat and mass transfer analogy was used to analyze the steam/noncondensable gas mixture boundary layer. Here, the Nusselt and Sherwood numbers in the gas phase were modified to incorporate the effects of condensate film roughness, suction, and developing flow. The predictions of the theoretical model for the experimental heat transfer coefficients at the top and bottom of the tube were reasonable. The calculated heat transfer coefficients at the top of the tube were higher than those at the bottom of it, as experimental results. As the temperature potential at the top of tube was lower than that at the bottom of it, the heat fluxes at the upper and lower portions of the tube were similar to each other. Generally speaking, however, the model predictions showed a good agreement with experimental data. The new empirical correlation proposed by Lee and Kim (2008) for the vertical tube was applied to the condensation of steam/noncondensable mixture in a horizontal tube. Nusselt theory and Chato correlation were used to calculate the heat transfer coefficients at top and bottom of the horizontal tube, respectively. The predictions of the new empirical correlation were good and very similar with the theoretical model. (author)

  11. Thermodynamic Characterization of Undefined Petroleum Fractions of Gas Condensate using Group Contribution

    Directory of Open Access Journals (Sweden)

    Uribe-Vargas Veronica

    2016-01-01

    Full Text Available A methodology proposed in a previous paper [Carreón-Calderón et al. (2012 Ind. Eng. Chem. Res. 51, 14188-14198] for thermodynamic characterization of undefined petroleum fractions was applied to gas-condensate fluids. Using this methodology, input parameters of cubic equations of state and their mixing rules, critical properties and chemical pseudostructures are determined for undefined fractions by minimizing their Gibbs free energy. The results show the feasibility of applying this approach to gas-condensate fluids without making use of either cubic equations of state or mixing rules with specific adjusted parameters for petroleum fluids. Besides, it is shown that the phase equilibrium envelopes of gas-condensate fluids are highly dependent on the critical properties assigned to the undefined petroleum fractions of such fluid fractions and less dependent on the equation used for modeling gas-condensate fluids as a whole. The Absolute Average Error (AAE considering the best arrangement is 1.79% in predicting the dew point.

  12. Market diffusion, technological learning, and cost-benefit dynamics of condensing gas boilers in the Netherlands

    NARCIS (Netherlands)

    Weiss, M.; Dittmar, L.; Junginger, H.M.; Patel, M.K.; Blok, K.

    2009-01-01

    High costs often prevent the market diffusion of novel and efficient energy technologies. Monitoring cost and price decline for these technologies is thus important in order to establish effective energy policy. Here, we present experience curves and cost-benefit analyses for condensing gas boilers

  13. Experimental phase behavior study of a five-component model gas condensate

    NARCIS (Netherlands)

    Shariati - Sarabi, A.; Straver, E.J.M.; Florusse, L.J.; Peters, C.J.

    2014-01-01

    In this work, the bubble points and dew points of a multicomponent mixture of methane, butane, heptane, decane and tetradecane as a model mixture representative of a gas condensate, have been measured experimentally. Ten samples with approximately the same composition were prepared and their

  14. Removal of fine particles in wet flue gas desulfurization system by heterogeneous condensation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, L.J.; Bao, J.J.; Yan, J.P.; Liu, J.H.; Song, S.J.; Fan, F.X. [Southeast University, Nanjing (China). School of Energy & Environment

    2010-01-01

    A novel process to remove fine particles with high efficiency by heterogeneous condensation in a wet flue gas desulfurization (WFGD) system is presented. A supersaturated vapor phase, necessary for condensational growth of fine particles, was achieved in the SO{sub 2} absorption zone and at the top of the wet FGD scrubber by adding steam in the gas inlet and above the scrubbing liquid inlet of the scrubber, respectively. The condensational grown droplets were then removed by the scrubbing liquid and a high-efficiency demister. The results show that the effectiveness of the WFGD system for removal of fine particles is related to the SO{sub 2} absorbent employed. When using CaCO{sub 3} and NH{sub 3} {center_dot} H{sub 2}O to remove SO{sub 2} from flue gas, the fine particle removal efficiencies are lower than those for Na2CO{sub 3} and water, and the morphology and elemental composition of fine particles are changed. This effect can be attributed to the formation of aerosol particles in the limestone and ammonia-based FGD processes. The performance of the WFGD system for removal of fine particles can be significantly improved for both steam addition cases, for which the removal efficiency increases with increasing amount of added steam. A high liquid to gas ratio is beneficial for efficient removal of fine particles by heterogeneous condensation of water vapor.

  15. Operando Spectroscopy of the Gas-Phase Aldol Condensation of Propanal over Solid Base Catalysts

    NARCIS (Netherlands)

    Hernández-giménez, Ana M.; Ruiz-martínez, Javier; Puértolas, Begoña; Pérez-ramírez, Javier; Bruijnincx, Pieter C. A.; Weckhuysen, Bert M.

    2017-01-01

    The gas-phase aldol condensation of propanal, taken as model for the aldehyde components in bio-oils, has been studied with a combined operando set-up allowing to perform FT-IR & UV–Vis diffuse reflectance spectroscopy (DRS) with on-line mass spectrometry (MS). The selected solid base catalysts, a

  16. Two-step condensation of the ideal Bose gas in highly anisotropic traps

    NARCIS (Netherlands)

    van Druten, N.J.; Ketterle, W.

    1997-01-01

    The ideal Bose gas in a highly anisotropic harmonic potential is studied. It is found that Bose-Einstein condensation occurs in two distinct steps as the temperature is lowered. In the first step the specific heat shows a sharp feature, but the system still occupies many one-dimensional quantum

  17. Outcome of endodontic treatment of teeth filled using lateral condensation versus vertical compaction (Schilder's technique).

    Science.gov (United States)

    Aqrabawi, Jamal A

    2006-02-15

    The purpose of this prospective clinical and radiographic investigation was to assess the treatment results following endodontic therapy of teeth filled with lateral condensation versus teeth filled with vertical compaction of warm gutta-percha. A total of 290 patients were treated using the standardized step-back technique for canal preparation, which were filled with either lateral condensation or vertical compaction in one single session. Five years later, the treatment results were assessed clinically and radiographically and related to the type of the obturation technique using Chi-square analysis. Of the 340 teeth that were reexamined, 160 teeth were filled with lateral condensation, and 180 teeth were filled with vertical condensation. The results showed a significantly higher success rate for the vertical compaction versus the lateral condensation technique of teeth presented with preoperative periapical lesions P<0.04. Regardless of the preoperative periapical status of the teeth, no statistically significant difference was found between the two techniques. The overall success rate of both filling techniques was 80.3%.

  18. The characteristics of operation of the Shatlyk gas condensate deposit

    Energy Technology Data Exchange (ETDEWEB)

    Zatov, G.A.; Friman, Yu.M.; Frumson, Yu.V.; Koshayev, T.K.; Stepanov, N.G.; Tverkovkin, S.M.

    1983-01-01

    Results are correlated of the operation of the Shatlyksk deposit for a 10 year period from the start of its development through 1982. The rates of gas withdrawal from the deposits are analyzed, along with the conditions for manifestation of elastic, water thrust modes, the characteristics of the studied wells and other issues. The results of modeling the advancement of stratum waters are cited. The modeling was performed on a computer (EVM) using a system of two dimensional, two phase filtration.

  19. Mercury removal from natural gas and associated condensates

    Energy Technology Data Exchange (ETDEWEB)

    Hennico, A.; Barthel, Y.; Courty, P. (Institut Francais du Petrole, 31 - Rueil-Malmaison (France). Direction Industrielle)

    1990-01-01

    IFP mercury trapping systems are based on CMG 273, the recently developed Procatalyse product which is the heart of IFP's gas phase and liquid phase mercury removal technology. This material, made of highly macroporous alumina supporting a metal sulfide, presents a very high reactivity towards mecury within a broad range of operating conditions, including those operating in the liquid phase. Characteristics of CMG 273 are presented. (orig.).

  20. The method of predicting the process of condensation of moisture and hydrate formation in the gas pipeline

    OpenAIRE

    Хвостова, Олена Вікторівна

    2014-01-01

    The problem of ensuring the required value of one of the natural gas quality indicators during its transportation to the consumer - moisture content is considered in the paper. The method for predicting possible moisture condensation and hydrate formation processes in gas pipelines considering mixing gas flows with different moisture content was developed.Predicting the moisture condensation and hydrate formation in gas pipelines is an actual task since a timely prevention of these processes ...

  1. Theoretical study on bubble formation and flow condensation in downflow channel with horizontal gas injection

    Science.gov (United States)

    Zhu, Kang; Li, Yanzhong; Wang, Jiaojiao; Ma, Yuan; Wang, Lei; Xie, Fushou

    2018-05-01

    Bubble formation and condensation in liquid pipes occur widely in industrial systems such as cryogenic propellant feeding system. In this paper, an integrated theoretical model is established to give a comprehensive description of the bubble formation, motion and condensation process. The model is validated by numerical simulations and bubble condensation experiments from references, and good agreements are achieved. The bubble departure diameter at the orifice and the flow condensation length in the liquid channel are predicted by the model, and effects of various influencing parameters on bubble behaviors are analyzed. Prediction results indicate that the orifice diameter, the gas feeding rate, and the liquid velocity are the primary influence factors on the bubble departure diameter. The interfacial heat transfer as well as the bubble departure diameter has a direct impact on the bubble flow condensation length, which increases by 2.5 times over a system pressure range of 0.1 0.4 MPa, and decreases by 85% over a liquid subcooling range of 5 30 K. This work could be beneficial to the prediction of bubble formation and flow condensation processes and the design of cryogenic transfer pipes.

  2. A condensation experiment in the accumulated conditions of noncondensable gas in a vertical tube

    International Nuclear Information System (INIS)

    Lee, Kwon Yeong; Kim, Moo Hwan

    2005-01-01

    Full text of publication follows: It has been well known that the presence of noncondensable gases in vapors can greatly inhibit the condensation process. Many analytical and experimental studies were conducted to investigate the effect of noncondensable gases on steam condensation for both stagnant and forced-convective situations either over a plate or outside a horizontal tube. Recently, several researches have been performed for the condensation in the presence of noncondensable gases taken place inside the vertical tube in order to give the information to design the passive containment cooling system (PCCS) in Simplified Boiling Water Reactor (SBWR). Generally, the experimental results showed that the heat transfer coefficient depends on inlet noncondensable gas mass fraction, inlet saturated steam temperature related with system pressure and inlet mixture Reynolds number. This research was performed for the System-integrated Modular Advanced ReacTor-Pilot (SMART-P), in which the remaining heat is removed from the core passively by Passive Residual Heat Removal System (PRHRS) condenser in a period of serious accident. The PRHRS is separated from working fluid loop, and pressurized by a nitrogen gas during the normal operation of SMART-P. But when the PRHRS starts operating, the nitrogen gas acts as a noncondensable gas and affects the heat transfer characteristics of the PRHRS. The experimental conditions of this study were almost similar with those of previous researches except the noncondensable gas was accumulated and remained inside the vertical tube. In the previous researches, the noncondensable gas was flowing with constant flow rate. Because of the condensate inside condenser tube, the accumulation of noncondensable gas could be developed inside the vertical tube. At steady-state condition the local temperatures and system pressure were measured to obtain heat transfer characteristics. This study also gave the information about the distribution of the

  3. Evaluation of non-condensable gas effect during LBLOCA in an OPR1000 Plant

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Seung Hun; Seul, Kwang-Won; Bang, Young-Seok; Lee, Jun Soo [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-05-15

    Gas accumulation in the nuclear power plant may cause diverse safety issues such as water hammer, pump cavitation and inadvertent valve actuation. The Nuclear Regulatory Commission (NRC) has published twenty Information Notices, two Generic Letters, and one NUREG report related to the issue of the gas accumulation. It has been considered that gas accumulation occurred since the beginning of commercial nuclear power plant operation and may occur in the currently operating plants. Gas accumulation in the Emergency Core Cooling System (ECCS) is the condition that did not consider in Accident Analysis of Final Safety Analysis Report or Technical Specification and may finally result in degradation or loss of the safety functions. In this paper, the effect of gas accumulation in the ECCS has been analyzed by modeling non-condensable gas injection during the operation of Safety Injection Tank (SIT) and Low Pressure Safety Injection (LPSI) under the LBLOCA condition. Gas accumulation in the ECCS has been dealt with one of significant safety issues in the operating nuclear power plants. In order to identify the effect of the non-condensable gas in Hanul unit 3 and 4, the sensitivity studies for gas quantity, location or injection time was conducted for high or low pressure condition. At high pressure condition, the injected gas induced the reduced SIT flow rate and the reduced period of SIT injection. The reflood PCT at 5 ft''3 condition was 1150 K which was 49K higher than that at no gas condition. At low pressure condition, the reduced flow rate and the increased reflood PCT were also identified. However, the PCT deviation due to different gas quantity was not large as much as that at high pressure condition. We concluded that it is necessary to evaluate the effect of the accumulated gas with the consideration of plant- specific conditions such as system pressure, accumulated location, gas quantity and injection time.

  4. High-efficiency condenser of steam from a steam-gas mixture

    Science.gov (United States)

    Milman, O. O.; Krylov, V. S.; Ptakhin, A. V.; Kondratev, A. V.; Yankov, G. G.

    2017-12-01

    The design of a module for a high-efficiency condenser of steam with a high content (up to 15%) of noncondensable gases (NCGs) with a nearly constant steam-gas mixture (SGM) velocity during the condensation of steam has been developed. This module provides the possibility to estimate the operational efficiency of six condenser zones during the motion of steam from the inlet to the SGM suction point. Some results of the experimental tests of the pilot high-efficiency condenser module are presented. The dependence of the average heat transfer coefficient k¯ on the volumetric NCG concentration v¯ has been derived. It is shown that the high-efficiency condenser module can provide a moderate decrease in k¯ from 4400-4600 to 2600-2800 W/(m2 K) at v¯ ≈ 0.5-9.0%. The heat transfer coefficient distribution over different module zones at a heat duty close to its nominal value has been obtained. From this distribution, it can be seen that the average heat transfer coefficient decreases to 2600 W/(m2 K) at an NCG concentration v¯ = 7.5%, but the first condenser sections ( 1- 3) retain high values of k¯ at a level of no lower than 3200 W/(m2 K), and the last sections operate less well, having k¯ at a level of 1700 W/(m2 K). The dependence of the average heat transfer coefficient on the water velocity in condenser tubes has been obtained at a nearly nominal duty such that the extrapolation of this dependence to the water velocity of 2 m/s may be expected to give k¯ = 5000 W/(m2 K) for relatively pure steam, but an increase in k¯ at v¯ = 8% will be smaller. The effect of the gas removal device characteristic on the operation of the high-efficiency condenser module is described. The design developed for the steam condenser of a gas-turbine plant with a power of 25 MW, a steam flow rate of 40.2 t/h, and a CO2 concentration of up to 12% with consideration for the results of performed studies is presented.

  5. Recent study of nanomaterials prepared by inert gas condensation ...

    Indian Academy of Sciences (India)

    ITO), ZnO, Al2O3, Ag2O, CdO, CuO, ZnSe:ZnO etc., were prepared by this technique and characterized. Results of some of these materials will be presented in this paper. In solid-state 207Pb NMR on PbF2 a separate signal due to the presence ...

  6. Experimental investigation of condensation and mixing during venting of a steam / non-condensable gas mixture into a pressure suppression pool

    Energy Technology Data Exchange (ETDEWEB)

    De Walsche, C.; Cachard, F. de

    2000-07-01

    Experiments have been performed in the LINX facility to investigate condensation and mixing phenomena in pressure Suppression Pools (SPs), in the context of the European Simplified Boiling Water Reactor (ESBWR) study. As a contribution to the TEPSS project of the 4th European Framework Programme, eight medium-scale, separate-effect tests were carried out in which constant steam/air flow rates were injected below the surface of a two-metre diameter water pool, maintained at constant pressure, through a large downward vent. The vessel pressure was regulated, the pool temperature rising until equilibrium conditions with the incoming gas were reached. The SP temperature distribution was measured, as well as the inlet and outlet gas flow rates, and the overall condensation rate was estimated using mass and heat balances. The test matrix was based on steam mass floret and air mass fraction of the injected gas, the vent immersion depth, and the vessel pressure. Overall, the condensation was shown to be efficient for all tests performed, even for high non-condensable gas concentrations of the injected gas. Thermal stratification above the vent outlet was shown to be moderate. The tests performed allowed a better understanding to be gained of the mechanisms of condensation and mixing in the SP and Wetwell, and results were incorporated into an ORACLE database, to be used for further model development. (authors)

  7. An analysis of the thermodynamic efficiency for exhaust gas recirculation-condensed water recirculation-waste heat recovery condensing boilers (EGR-CWR-WHR CB)

    International Nuclear Information System (INIS)

    Lee, Chang-Eon; Yu, Byeonghun; Lee, Seungro

    2015-01-01

    This study presents fundamental research on the development of a new boiler that is expected to have a higher efficiency and lower emissions than existing boilers. The thermodynamic efficiency of exhaust gas recirculation-condensed water recirculation-waste heat recovery condensing boilers (EGR-CWR-WHR CB) was calculated using thermodynamic analysis and was compared with other boilers. The results show the possibility of obtaining a high efficiency when the temperature of the exhaust gas is controlled within 50–60 °C because water in the exhaust gas is condensed within this temperature range. In addition, the enthalpy emitted by the exhaust gas for the new boiler is smaller because the amount of condensed water is increased by the high dew-point temperature and the low exhaust gas temperature. Thus, the new boiler can obtain a higher efficiency than can older boilers. The efficiency of the EGR-CWR-WHR CB proposed in this study is 93.91%, which is 7.04% higher than that of existing CB that is currently used frequently. - Highlights: • The study presents the development of a new boiler expected to have a high efficiency. • Thermodynamic efficiency of EGR-CWR-WHR condensing boiler was calculated. • Efficiency of EGR-CWR-WHR CB is 93.91%, which is 7.04% higher than existing CB

  8. Gas dynamics, optics and chemistry of an aircraft condensable wake

    Energy Technology Data Exchange (ETDEWEB)

    Grinats, E.S.; Kashevarov, A.V.; Stasenko, A.L. [Central Aerohydrodynamic Inst., Zhukovsky (Russian Federation)

    1997-12-31

    Prediction of the properties of a jet-and-vortex wake from an individual airplane is of great interest as the first step to assessment of the possible global changes in the atmosphere due to the world civil aviation. Several mathematical models of the different regions of an aircraft wake and corresponding numerical results are presented. The axisymmetric exhaust jet was simulated on the base of the well-known k-{epsilon} model of turbulence. Jet chemistry was investigated on the base of kinetic scheme of the gas phase reactions of enriched by including chemisorption by water droplets of several species and by taking into account of the photochemical processes. In the 3D far wake model, the numerical results for distribution of species exhausted by the engines and entrapped by the velocity field of two parallel vortices are shown. (R.P.) 7 refs.

  9. Gas dynamics, optics and chemistry of an aircraft condensable wake

    Energy Technology Data Exchange (ETDEWEB)

    Grinats, E S; Kashevarov, A V; Stasenko, A L [Central Aerohydrodynamic Inst., Zhukovsky (Russian Federation)

    1998-12-31

    Prediction of the properties of a jet-and-vortex wake from an individual airplane is of great interest as the first step to assessment of the possible global changes in the atmosphere due to the world civil aviation. Several mathematical models of the different regions of an aircraft wake and corresponding numerical results are presented. The axisymmetric exhaust jet was simulated on the base of the well-known k-{epsilon} model of turbulence. Jet chemistry was investigated on the base of kinetic scheme of the gas phase reactions of enriched by including chemisorption by water droplets of several species and by taking into account of the photochemical processes. In the 3D far wake model, the numerical results for distribution of species exhausted by the engines and entrapped by the velocity field of two parallel vortices are shown. (R.P.) 7 refs.

  10. Simulation of Flow Behavior of Gas Condensate at Low Interfacial Tension

    DEFF Research Database (Denmark)

    Wang, Peng; Stenby, Erling Halfdan; Pope, Gary A.

    1996-01-01

    A vertical, long-core experiment of natural depletion of a gas condensate that was conducted by Elf Aquitaine is simulated by an equation-of-state (EOS) compositional simulator, UTCOMP. The Peng-Robinson (PR) EOS is used for phase-behavior calculation. Because of low interfactial tension (IFT......) in the measurement, more attention is paid to the influence of IFT on gas/oil flow behavior. Two different types of model are used to compute the relative permeability. Model I is a Corey-type model combined with the capillary number concept. Model II is a modified form of the model proposed by Coats.The simulation...... results indicate that the effect of low IFT on relative permeability can be reasonably described by the two models selected, although the producing gas-oil ratio (GOR) obtained using Model I deviates somewhat from the experimental values in later depletion stages. The condensed liquid can be a mobile...

  11. Flue gas moisture capacity calculation at the outlet of the condensation heat recovery unit

    Directory of Open Access Journals (Sweden)

    Galashov Nikolay

    2017-01-01

    Full Text Available As a result, study equation has been obtained which determine the flue gas moisture capacity at the outlet of the condensation heat recovery unit with an error of less than 1%. It possible to at the temperature of the flue gas below the dew point and the known air-fuel ratio efficient. The equation can be used to calculate plants operating on products of gas combustion without Use of tables and programs for calculating the water-vapor saturation pressure.

  12. Terahertz Active Photonic Crystals for Condensed Gas Sensing

    Directory of Open Access Journals (Sweden)

    Karl Unterrainer

    2011-06-01

    Full Text Available The terahertz (THz spectral region, covering frequencies from 1 to 10 THz, is highly interesting for chemical sensing. The energy of rotational and vibrational transitions of molecules lies within this frequency range. Therefore, chemical fingerprints can be derived, allowing for a simple detection scheme. Here, we present an optical sensor based on active photonic crystals (PhCs, i.e., the pillars are fabricated directly from an active THz quantum-cascade laser medium. The individual pillars are pumped electrically leading to laser emission at cryogenic temperatures. There is no need to couple light into the resonant structure because the PhC itself is used as the light source. An injected gas changes the resonance condition of the PhC and thereby the laser emission frequency. We achieve an experimental frequency shift of 10−3 times the center lasing frequency. The minimum detectable refractive index change is 1.6 × 10−5 RIU.

  13. Hydrogen condensation products of Turkmenistan gas fields as motor fuel components

    Energy Technology Data Exchange (ETDEWEB)

    Kul-dzhaev, B.A.; Sergienko, S.R.; Tsibrova, E.G.

    1985-07-01

    Technical data are provided in tabular form on the composition of hydrocarbon condensation products obtained from various gas fields in Turkmenia, with an analysis of their usefulness as gasoline and diesel fuels. For example, high-paraffin condensates are characterized by low octane numbers (30-50) of the gasoline fraction (150-180/sup 0/C). However, lowering the temperature at the end of distillation to 120-130/sup 0/C increased the octane number to 73, one point higher than required by State Standards for automobile gasoline A-72. The cetane number of diesel fuels in general exceed the State Standards, especially in the case of fractions 150/sup 0/C and 180/sup 0/C of the high-paraffin condensates obtained from the Shatlyk site. Summarized data are presented on the suitability of the products obtained from the different site for the different types of fuels. 4 references.

  14. Effect of disorder on condensation in the lattice gas model on a random graph.

    Science.gov (United States)

    Handford, Thomas P; Dear, Alexander; Pérez-Reche, Francisco J; Taraskin, Sergei N

    2014-07-01

    The lattice gas model of condensation in a heterogeneous pore system, represented by a random graph of cells, is studied using an exact analytical solution. A binary mixture of pore cells with different coordination numbers is shown to exhibit two phase transitions as a function of chemical potential in a certain temperature range. Heterogeneity in interaction strengths is demonstrated to reduce the critical temperature and, for large-enough degreeS of disorder, divides the cells into ones which are either on average occupied or unoccupied. Despite treating the pore space loops in a simplified manner, the random-graph model provides a good description of condensation in porous structures containing loops. This is illustrated by considering capillary condensation in a structural model of mesoporous silica SBA-15.

  15. Study of the mobility activation in ZnSe thin films deposited using inert gas condensation

    Directory of Open Access Journals (Sweden)

    Jeewan Sharma

    2017-12-01

    Full Text Available ZnSe thin films were synthesized on glass substrates using the inert gas condensation technique at substrate temperature ranging from 25 °C to 100 °C. The hexagonal structure and average crystallite size (6.1–8.4 nm were determined from X-ray diffraction data. The transient photoconductivity was investigated using white light of intensity 8450 lx to deduce the effective density of states (Neff in the order of 1.02 × 1010–13.90 × 1010 cm−3, the frequency factor (S in the range 2.5 × 105–24.6 × 105 s−1 and the trap depth (E ranging between 0.37–0.64 eV of these films. The trap depth study revealed three different types of levels with quasi-continuous distribution below the conduction band. An increase in the photoconductivity was observed as a result of the formation of potential barriers (Vb and of the increase of carrier mobility at the crystallite boundaries. The study of the dependence of various mobility activation parameters on the deposition temperature and the crystallite size has provided better understanding of the mobility activation mechanism.

  16. Condensing species from flue gas in Puertollano gasification power plant, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Oriol Font; Xavier Querol; Felica Plana; Pilar Coca; Silvia Burgos; Francisco Garcia Pena [Institute of Earth Sciences ' Jaume Almera' , Barcelona (Spain). Environmental Geology

    2006-10-15

    The occurrence and distribution of trace elements (Pb, Zn, As, Ge, Cd, Tl, Bi, Sn, and also Ni, Fe and V) in condensates arising from coal gasification was investigated through the study of samples physically deposited on the gas cooling system from the Puertollano IGCC 335 MW power plant. These highly metal enriched samples are suitable for a comprehensive evaluation of the mode of occurrence of these elements in IGCC fly ash. Pb, Zn, Ge, and Fe sulfides, Ni-Fe arsenides, Ge and V oxides as well as traces of K chloride and Pb, Zn and Fe sulfates were determined as the major bearing phases for these elements. Three condensation zones were differentiated as function of the condensation temperatures and metal content: 1. Pb zone (520-750{sup o}C), characterized by the dominance of galena (70-90% of the main crystalline phases), and by the condensation of pyrrhotite and nickeline. 2. Ge-Zn-Pb zone (520-470{sup o}C), with sphalerite and wurzite being the dominant crystalline phases (over 40%), and Ge compounds, GeS{sub 2} and GeO{sub 2}, reaching 30% of the bulk condensates. 3. Zn zone (300-400{sup o}C), characterized by the dominance of Zn sulfides (over 85% of the main crystalline phases). The results obtained from these highly metalliferous condensates show similar forms of occurrence for the studied elements to those obtained in the bulk Puertollano IGCC fly ash (by using XAFS spectroscopy), where the contents of these elements are much lower. Furthermore, the sequential condensation of sulfides during coal gasification is similar to that from volcanic fumaroles, and may thus promote a better understanding of volcanic deposits. 23 refs., 7 figs., 5 tabs.

  17. Condensed Fraction of an Atomic Bose Gas Induced by Critical Correlations

    International Nuclear Information System (INIS)

    Smith, Robert P.; Tammuz, Naaman; Campbell, Robert L. D.; Hadzibabic, Zoran; Holzmann, Markus

    2011-01-01

    We study the condensed fraction of a harmonically trapped atomic Bose gas at the critical point predicted by mean-field theory. The nonzero condensed fraction f 0 is induced by critical correlations which increase the transition temperature T c above T c MF . Unlike the T c shift in a trapped gas, f 0 is sensitive only to the critical behavior in the quasiuniform part of the cloud near the trap center. To leading order in the interaction parameter a/λ 0 , where a is the s-wave scattering length and λ 0 the thermal wavelength, we expect a universal scaling f 0 ∝(a/λ 0 ) 4 . We experimentally verify this scaling using a Feshbach resonance to tune a/λ 0 . Further, using the local density approximation, we compare our measurements with the universal result obtained from Monte Carlo simulations for a uniform system, and find excellent quantitative agreement.

  18. Critical behavior of the ideal-gas Bose-Einstein condensation in the Apollonian network.

    Science.gov (United States)

    de Oliveira, I N; dos Santos, T B; de Moura, F A B F; Lyra, M L; Serva, M

    2013-08-01

    We show that the ideal Boson gas displays a finite-temperature Bose-Einstein condensation transition in the complex Apollonian network exhibiting scale-free, small-world, and hierarchical properties. The single-particle tight-binding Hamiltonian with properly rescaled hopping amplitudes has a fractal-like energy spectrum. The energy spectrum is analytically demonstrated to be generated by a nonlinear mapping transformation. A finite-size scaling analysis over several orders of magnitudes of network sizes is shown to provide precise estimates for the exponents characterizing the condensed fraction, correlation size, and specific heat. The critical exponents, as well as the power-law behavior of the density of states at the bottom of the band, are similar to those of the ideal Boson gas in lattices with spectral dimension d(s)=2ln(3)/ln(9/5)~/=3.74.

  19. Integration of gas phase condensed nanoparticles in YBa_2Cu_3O_7_-_δ multilayers

    International Nuclear Information System (INIS)

    Sparing, Maria

    2012-01-01

    The control and targeted variation of nanoparticles properties is a central challenge in research on particle induced defects in YBa_2Cu_3O_7_-_δ. Using a combined Sputter-PLD system with inert gas condensation particle size and density integrated into the YBCO multilayers were varied independently. The cooling process influences the electrical properties of the multilayers. The effect of HfO2 and FePt nanoparticles on the structural and electrical properties was studied.

  20. Water desalting schemes when using heat gas-vapor mixture in front of contact condenser

    OpenAIRE

    Kuznetsova, Svitlana A.

    2016-01-01

    Ukraine is a country with low quality of fresh water; there are regions with its deficiency. One of the possible solutions to this problem is the desalination of the brackish water from surface and groundwater sources by using heat of the mixture before the contact condenser in gas-steam turbine plants. The plants produce electricity and heat energy for the needs of the industrial, agricultural complexes and the population of Kherson, Nikolaev and Odessa regions. The studies were carried out ...

  1. Assessment of MELCOR condensation models with the presence of noncondensable gas in natural convection flow regime

    International Nuclear Information System (INIS)

    Yoon, Dhongik S; Jo, HangJin; Corradini, Michael L

    2017-01-01

    Condensation of steam vapor is an important mode of energy removal from the reactor containment. The presence of noncondensable gas complicates the process and makes it difficult to model. MELCOR, one of the more widely used system codes for containment analyses, uses the heat and mass transfer analogy to model condensation heat transfer. To investigate previously reported nodalization-dependence in natural convection flow regime, MELCOR condensation model as well as other models are studied. The nodalization-dependence issue is resolved by using physical length from the actual geometry rather than node size of each control volume as the characteristic length scale for MELCOR containment analyses. At the transition to turbulent natural convection regime, the McAdams correlation for convective heat transfer produces a better prediction compared to the original MELCOR model. The McAdams correlation is implemented in MELCOR and the prediction is validated against a set of experiments on a scaled AP600 containment. The MELCOR with our implemented model produces improved predictions. For steam molar fractions in the gas mixture greater than about 0.58, the predictions are within the uncertainty margin of the measurements. The simulation results still underestimate the heat transfer from the gas-steam mixture, implying that conservative predictions are provided.

  2. Effect of capillary condensation on gas transport properties in porous media

    Science.gov (United States)

    Yoshimoto, Yuta; Hori, Takuma; Kinefuchi, Ikuya; Takagi, Shu

    2017-10-01

    We investigate the effect of capillary condensation on gas diffusivity in porous media composed of randomly packed spheres with moderate wettability. To simulate capillary phenomena at the pore scale while retaining complex pore networks of the porous media, we employ density functional theory (DFT) for coarse-grained lattice gas models. The lattice DFT simulations reveal that capillary condensations preferentially occur at confined pores surrounded by solid walls, leading to the occlusion of narrow pores. Consequently, the characteristic lengths of the partially wet structures are larger than those of the corresponding dry structures with the same porosities. Subsequent gas diffusion simulations exploiting the mean-square displacement method indicate that while the effective diffusion coefficients significantly decrease in the presence of partially condensed liquids, they are larger than those in the dry structures with the same porosities. Moreover, we find that the ratio of the porosity to the tortuosity factor, which is a crucial parameter that determines an effective diffusion coefficient, can be reasonably related to the porosity even for the partially wet porous media.

  3. Gas Condensates onto a LHC Type Cryogenic Vacuum System Subjected to Electron Cloud

    CERN Multimedia

    Baglin, V

    2004-01-01

    In the Large Hadron Collider (LHC), the gas desorbed via photon stimulated molecular desorption or electron stimulated molecular desorption will be physisorbed onto the beam screen held between 5 and 20 K. Studies of the effects of the electron cloud onto a LHC type cryogenic vacuum chamber have been done with the cold bore experiment (COLDEX) installed in the CERN Super Proton Synchrotron (SPS). Experiments performed with gas condensates such as H2, H2O, CO and CO2 are described. Implications for the LHC design and operation are discussed.

  4. Special features in choosing a development procedure for deep gas condensate fields with small reserves

    Energy Technology Data Exchange (ETDEWEB)

    Rassokhin, G V; Soshnin, N M

    1971-01-01

    In planning the development and production schedule for fields with small gas-condensate reserves, the following factors need to be considered: capital investment per unit of production, value of produced gas, ultimate recovered reserves, geological structure of the field, depth of well, heterogeneity of producing sands, etc. The importance of such factors is discussed and it is shown that for small fields, the parameter of minimum net expense cannot be used as a planning tool. Both geological and economic factors must be included in field development.

  5. A Preliminary Study of Transverse Curvature Effects on Condensation Heat Transfer on Vertical Tube in the Presence of Non-condensable Gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yeon Gun; Kim, Sin [Jeju National Univ., Jeju (Korea, Republic of); Jerng, Dong Wook [Chung Ang Univ., Seoul (Korea, Republic of)

    2013-10-15

    In this study, the effect of the transverse curvature on the condensation HTC on a vertical tube in the presence of air is preliminarily investigated by using the analysis of boundary layer for free convective heat transfer. The results indicate that the heat transfer performance can be enhanced as the outer diameter of condenser tubes is small. To confirm this curvature effect, an experimental program to obtain the condensation heat transfer data for various values of tube diameter is indispensable. Currently, by a joint research project of Jeju National University and Chung-Ang University, a condensation test facility is being designed and constructed to acquire the condensation HTC data as shown in Fig. 3. From a series of experiment on a single vertical tube, the effects of not only the tube diameter but the inclination, the existence of fins and the local velocity of a bulk mixture by natural circulation will be evaluated precisely. An empirical correlation for the condensation heat transfer of a steam-air mixture will also be developed for design optimization and performance evaluation of the PCCS. The Passive Containment Cooling System (PCCS) provides passive means to remove the decay heat and protect the integrity of the containment during severe accidents. Korea, in which all the NPPs employ the concrete containment, may adopt a PCCS using internal condensers. In the event of the loss-of-coolant accident (LOCA), steam released from the reactor coolant system is mixed with air inside the containment and condensed on the outer surface of inclined condenser tubes. It is noted that, among previous theoretical and empirical models for condensation on outer wall in the presence of non-condensable gas, no one took into account the effect of a tube diameter. Though the condensation heat transfer coefficient may vary with transverse curvature of condenser tubes, such a curvature effect has not been reported so far. In this study, a preliminary analysis is conducted

  6. A Preliminary Study of Transverse Curvature Effects on Condensation Heat Transfer on Vertical Tube in the Presence of Non-condensable Gas

    International Nuclear Information System (INIS)

    Lee, Yeon Gun; Kim, Sin; Jerng, Dong Wook

    2013-01-01

    In this study, the effect of the transverse curvature on the condensation HTC on a vertical tube in the presence of air is preliminarily investigated by using the analysis of boundary layer for free convective heat transfer. The results indicate that the heat transfer performance can be enhanced as the outer diameter of condenser tubes is small. To confirm this curvature effect, an experimental program to obtain the condensation heat transfer data for various values of tube diameter is indispensable. Currently, by a joint research project of Jeju National University and Chung-Ang University, a condensation test facility is being designed and constructed to acquire the condensation HTC data as shown in Fig. 3. From a series of experiment on a single vertical tube, the effects of not only the tube diameter but the inclination, the existence of fins and the local velocity of a bulk mixture by natural circulation will be evaluated precisely. An empirical correlation for the condensation heat transfer of a steam-air mixture will also be developed for design optimization and performance evaluation of the PCCS. The Passive Containment Cooling System (PCCS) provides passive means to remove the decay heat and protect the integrity of the containment during severe accidents. Korea, in which all the NPPs employ the concrete containment, may adopt a PCCS using internal condensers. In the event of the loss-of-coolant accident (LOCA), steam released from the reactor coolant system is mixed with air inside the containment and condensed on the outer surface of inclined condenser tubes. It is noted that, among previous theoretical and empirical models for condensation on outer wall in the presence of non-condensable gas, no one took into account the effect of a tube diameter. Though the condensation heat transfer coefficient may vary with transverse curvature of condenser tubes, such a curvature effect has not been reported so far. In this study, a preliminary analysis is conducted

  7. MARS-KS Code Assessment for Condensation Heat Transfer in Horizontal Tube with the Presence of Non-Condensable Gas using Purdue Experiment

    International Nuclear Information System (INIS)

    Jeon, Seong Su; Lee, Byung Chul; Park, Ju Yeop; Seul, Kwang Won

    2011-01-01

    In South Korea, advanced power reactor plus (APR+), as a Korean specific reactor, is currently under development for the export strategy. In order to raise competitiveness of the APR+ in the world market, it is necessary to develop the original technology for the improved technology, economics, and safety features. For this purpose, a passive auxiliary feedwater system (PAFS) was adopted as an improved safety design concept of APR+: and then there have been many efforts to develop the PAFS. According to PAFS design concept, PAFS can completely replace the auxiliary feedwater system. When the design basis accident, in which feedwater is unavailable, occurs, the PAFS can remove the residual heat in the core and then prevent the core damage. In the PAFS with the horizontal type heat exchanger, two-phase natural circulation, condensation heat transfer in tube, boiling heat transfer in pool, natural convection in pool, etc. are considered as very important thermalhydraulic phenomena (see Fig. 1). Compared with the vertical heat exchanger from these phenomena, the major difference of the horizontal heat exchanger is the condensation heat transfer phenomena in the tube side. There have been many efforts to understand the condensation heat transfer with in the presence of NC gas in tube but most researches focused on the condensation heat transfer in vertical tube. Therefore the details of the condensation heat transfer in the presence of NC gas in horizontal condenser tubes are not well understood. In order to develop the safety evaluation system for APR+ PAFS, it is required to evaluate the capability and applicability of the MARS-KS code for modeling the condensation heat transfer in the horizontal tube with NC gas because many heat transfer correlations in MARS-KS are known to have much uncertainty. In particular, there is no reliable model for the condensation phenomena in horizontal tube with NC gas. In order to assess the MARS-KS code results and identify the

  8. Study of flue gas condensing for biofuel fired heat and power plants; Studie av roekgaskondensering foer biobraensleeldade kraftvaermeanlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Axby, Fredrik; Gustafsson, J O; Nystroem, Johan; Johansson, Kent

    2000-11-01

    This report considers questions regarding flue gas condensing plants connected to bio-fuelled heat and power plants. The report consists of two parts, one where nine existing plants are described regarding technical issues and regarding the experience from the different plants. Part two is a theoretical study where heat balance calculations are made to show the technical and economical performance in different plant configurations and operating conditions. Initially the different parts in the flue gas condensing plant are described. Tube, plate and scrubber condensers are described briefly. The different types of humidifiers are also described, rotor, cross-stream plate heat exchanger and scrubber. Nine flue gas-condensing plants have been visited. The plants where chosen considering it should be bio-fuel fired plant primarily heat and power plants. Furthermore we tried to get a good dissemination considering plant configuration, supplier, geographical position, operating situation and plant size. The description of the different plants focuses on the flue gas condenser and the belonging components. The fuel, flue gas and condensate composition is described as well as which materials are used in the different parts of the plant. The experience from operating the plants and the reasons of why they decided to chose the actual condenser supplier are reported.

  9. Effect of carrier gas pressure on condensation in a supersonic nozzle

    International Nuclear Information System (INIS)

    Wyslouzil, B.E.; Wilemski, G.; Beals, M.G.; Frish, M.B.

    1994-01-01

    Supersonic nozzle experiments were performed with a fixed water or ethanol vapor pressure and varying amounts of nitrogen to test the hypothesis that carrier gas pressure affects the onset of condensation. Such an effect might occur if nonisothermal nucleation were important under conditions of excess carrier gas in the atmospheric pressure range, as has been suggested by Ford and Clement [J. Phys. A 22, 4007 (1989)]. Although a small increase was observed in the condensation onset temperature as the stagnation pressure was reduced from 3 to 0.5 atm, these changes cannot be attributed to any nonisothermal effects. The pulsed nozzle experiments also exhibited two interesting anomalies: (1) the density profiles for the water and ethanol mixtures were shifted in opposite directions from the dry N 2 profile; (2) a long transient period was required before the nozzle showed good pulse-to-pulse repeatability for condensible vapor mixtures. To theoretically simulate the observed onset behavior, calculations of nucleation and droplet growth in the nozzle were performed that took into account two principal effects of varying the carrier gas pressure: (1) the change in nozzle shape due to boundary layer effects and (2) the variation in the heat capacity of the flowing gas. Energy transfer limitations were neglected in calculating the nucleation rates. The trend of the calculated results matched that of the experimental results very well. Thus, heat capacity and boundary layer effects are sufficient to explain the experimental onset behavior without invoking energy transfer limited nucleation. The conclusions about the rate of nucleation are consistent with those obtained recently using an expansion cloud chamber, but are at odds with results from thermal diffusion cloud chamber measurements

  10. Gas separation techniques in nuclear facilities

    International Nuclear Information System (INIS)

    Hioki, Hideaki; Morisue, Tetsuo; Ohno, Masayoshi

    1983-01-01

    The literatures concerning the gas separation techniques which are applied to the waste gases generated from nuclear power plants and nuclear fuel reprocessing plants, uranium enrichment and the instrumentation of nuclear facilities are reviewed. The gas permeability and gas separation performance of membranes are discussed in terms of rare gas separation. The investigation into the change of the gas permeability and mechanical properties of membranes with exposure to radiation is reported. The theoretical investigation of the separating cells used for the separation of rare gas and the development of various separating cells are described, and the theoretical and experimental investigations concerning rare gas separation using cascades are described. The application of membrane method to nuclear facilities is explained showing the examples of uranium enrichment, the treatment of waste gases from nuclear reactor buildings and nuclear fuel reprocessing plants, the monitoring of low level β-emitters in stacks, the detection of failed fuels and the detection of water leak in fast breeder reactors. (Yoshitake, I.)

  11. Advances in SAW gas sensors based on the condensate-adsorption effect.

    Science.gov (United States)

    Liu, Jiuling; Wang, Wen; Li, Shunzhou; Liu, Minghua; He, Shitang

    2011-01-01

    A surface-acoustic-wave (SAW) gas sensor with a low detection limit and fast response for volatile organic compounds (VOCs) based on the condensate-adsorption effect detection is developed. In this sensor a gas chromatography (GC) column acts as the separator element and a dual-resonator oscillator acts as the detector element. Regarding the surface effective permittivity method, the response mechanism analysis, which relates the condensate-adsorption effect, is performed, leading to the sensor performance prediction prior to fabrication. New designs of SAW resonators, which act as feedback of the oscillator, are devised in order to decrease the insertion loss and to achieve single-mode control, resulting in superior frequency stability of the oscillator. Based on the new phase modulation approach, excellent short-term frequency stability (±3 Hz/s) is achieved with the SAW oscillator by using the 500 MHz dual-port resonator as feedback element. In a sensor experiment investigating formaldehyde detection, the implemented SAW gas sensor exhibits an excellent threshold detection limit as low as 0.38 pg.

  12. Half-space problem of unsteady evaporation and condensation of polyatomic gas

    Science.gov (United States)

    Inaba, Masashi; Yano, Takeru

    2016-11-01

    On the basis of polyatomic version of the ellipsoidal-statistical Bhatnager-Gross-Krook (ES-BGK) model, we consider time-periodic gas flows in a semi-infinite expanse of an initially equilibrium polyatomic gas (methanol) bounded by its planar condensed phase. The kinetic boundary condition at the vapor-liquid interface is assumed to be the complete condensation condition with periodically time-varying macroscopic variables (temperature, saturated vapor density and velocity of the interface), and the boundary condition at infinity is the local equilibrium distribution function. The time scale of variation of macroscopic variables is assumed to be much larger than the mean free time of gas molecules, and the variations of those from a reference state are assumed to be sufficiently small. We numerically investigate thus formulated time-dependent half-space problem for the polyatomic version of linearized ES-BGK model equation with the finite difference method for the case of the Strouhal number Sh=0.01 and 0.1. It is shown that the amplitude of the mass flux at the interface is the maximum, and the phase difference in time between the mass flux and v∞ - vℓ (v∞: vapor velocity at infinity, vℓ: velocity of the vapor-liquid interface) is the minimum absolute value, when the phase difference in time between the liquid surface temperature (the saturated vapor density) and the velocity of interface is close to zero.

  13. Characterization of the vadose zone above a shallow aquifer contaminated with gas condensate hydrocarbons

    International Nuclear Information System (INIS)

    Sublette, K.; Duncan, K.; Thoma, G.; Todd, T.

    2002-01-01

    A gas production site in the Denver Basin near Ft. Lupton, Colorado has leaked gas condensate hydrocarbons from an underground concrete tank used to store produced water. The leak has contaminated a shallow aquifer. Although the source of pollution has been removed, a plume of hydrocarbon contamination still remains for nearly 46 m from the original source. An extensive monitoring program was conducted in 1993 of the groundwater and saturated sediments. The objective was to determine if intrinsic aerobic or anaerobic bioremediation of hydrocarbons occurred at the site at a rate that would support remediation. Geochemical indicators of hydrogen biodegradation by microorganisms in the saturated zone included oxygen depletion, increased alkalinity, sulfate depletion, methane production and Fe2+ production associated with hydrogen contamination. The presence of sulfate-reducing bacteria and methanogens was also much higher in the contaminated sediments. Degraded hydrocarbon metabolites were found in contaminated groundwater. An extensive characterization of the vadose zone was conducted in which the vadose zone was sample in increments of 15 cm from the surface to the water table at contaminated and non contaminated sites. The samples were tested for individual C3+ hydrocarbons, methane, CO2, total organic carbon, total inorganic carbon, and total petroleum hydrocarbons. The vadose zone consisted of an active and aerobic bioreactor fueled by condensate hydrocarbons transported into the unsaturated zone by evaporation of hydrocarbons at the water table. It was concluded that the unsaturated zone makes an important contribution to the natural attenuation of gas condensate hydrocarbons in the area. 17 refs., 2 tabs., 28 figs

  14. Separation of submicron particles from biofuel combustion with flue gas condensation or wet condensing electrostatic precipitator. Analysis of possibilities; Avskiljning av submikrona partiklar vid biobraenslefoerbraenning med roekgaskondensering eller kondenserande vaata elfilter. Analys av moejligheterna

    Energy Technology Data Exchange (ETDEWEB)

    Roennbaeck, Marie; Gustavsson, Lennart [Swedish National Testing and Research Inst., Boraas (Sweden)

    2006-11-15

    Dust particles in flue gas larger than 1 {mu}m are well separated by conventional techniques, while submicron particles are poorly separated. As the use of biofuels with high ash content is increasing, as well as knowledge about negative health effects from inhalation of submicron particles, the interest for reduction of emissions of submicron particles will probably increase. The aim of this project is to investigate possible techniques for separation of submicron particles during flue gas condensation through modification of conventional technique, or with available techniques not usually used with combustion of biofuels, e.g. a wet electrostatic precipitator. Mechanisms for separation of dust particles are briefly described. Cyclones separates particles larger than about 1 {mu}m. Fabric filters separates all particles sizes, but the efficiency reduces as the size reduces. In flue gas condensers and scrubbers the speed and size of water droplets are important for the reduction efficiency. Dry electrostatic precipitators work for all particle sizes, but with reduced efficiency for sizes between 0.1 and 3 {mu}m. Wet electrostatic precipitators separates submicron particles much better. One reason for this is that the potential between the electrodes can be higher. Among conventional flue gas condensers and scrubbers there are two types that, properly designed, can separate submicron particles, namely 'type venturi scrubbers', i.e. a scrubber where a high flue gas velocity is used to form many, small water droplets by friction forces in a nozzle, and 'type scrubber with nozzles', i.e. a scrubber where nozzles supply droplets to the flue gas. For a scrubber with nozzles, the falling velocity of the droplets must be lower and the size smaller than is common today. Also the wet electrostatic precipitator separates submicron particles with high efficiency. They are used today mainly for problematic particles, e.g. sticky or corrosive ones, or for

  15. Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, Duane J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, William R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-01-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream, LAW Off-Gas Condensate, from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of canistered glass waste forms. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to be within acceptable concentration ranges in the LAW glass. Diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the impact of potential future disposition of this stream in the Hanford tank farms, and investigates auxiliary evaporation to enable another disposition path. Unless an auxiliary evaporator is used, returning the stream to the tank farms would require evaporation in the 242-A evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter

  16. Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    International Nuclear Information System (INIS)

    Adamson, Duane J.; Nash, Charles A.; McCabe, Daniel J.; Crawford, Charles L.; Wilmarth, William R.

    2014-01-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream, LAW Off-Gas Condensate, from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of canistered glass waste forms. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to be within acceptable concentration ranges in the LAW glass. Diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the impact of potential future disposition of this stream in the Hanford tank farms, and investigates auxiliary evaporation to enable another disposition path. Unless an auxiliary evaporator is used, returning the stream to the tank farms would require evaporation in the 242-A evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter

  17. Vortices in atomic Bose-Einstein condensates in the large-gas-parameter region

    International Nuclear Information System (INIS)

    Nilsen, J.K.; Mur-Petit, J.; Guilleumas, M.; Polls, A.; Hjorth-Jensen, M.

    2005-01-01

    In this work we compare the results of the Gross-Pitaevskii and modified Gross-Pitaevskii equations with ab initio variational Monte Carlo calculations for Bose-Einstein condensates of atoms in axially symmetric traps. We examine both the ground state and excited states having a vortex line along the z axis at high values of the gas parameter and demonstrate an excellent agreement between the modified Gross-Pitaevskii and ab initio Monte Carlo methods, both for the ground and vortex states

  18. Assessment of natural hydrocarbon bioremediation at two gas condensate production sites

    International Nuclear Information System (INIS)

    Barker, G.W.; Raterman, K.T.; Fisher, J.B.; Corgan, J.M.; Trent, G.L.; Brown, D.R.; Sublette, K.L.

    1995-01-01

    Condensate liquids are present in soil and groundwater at two gas production sites in the Denver-Julesburg Basin operated by Amoco. These sites have been closely monitored since July 1993 to determine whether intrinsic aerobic or anaerobic bioremediation of hydrocarbons occurs at a sufficient rate and to an adequate endpoint to support a no-intervention decision. Groundwater monitoring and analysis of soil cores strongly suggest that intrinsic bioremediation is occurring at these sites by multiple pathways, including aerobic oxidation, Fe(III) reduction, and sulfate reduction

  19. Two-Step Condensation of the Ideal Bose Gas in Highly Anisotropic Traps

    International Nuclear Information System (INIS)

    van Druten, N.J.; Ketterle, W.

    1997-01-01

    The ideal Bose gas in a highly anisotropic harmonic potential is studied. It is found that Bose-Einstein condensation occurs in two distinct steps as the temperature is lowered. In the first step the specific heat shows a sharp feature, but the system still occupies many one-dimensional quantum states. In the second step, at a significantly lower temperature, the ground state becomes macroscopically occupied. It should be possible to verify these predictions using present-day atom traps. The two-step behavior can occur in a rather general class of anisotropic traps, including the box potential. copyright 1997 The American Physical Society

  20. Characterization of condensed phase nitric acid particles formed in the gas phase

    Institute of Scientific and Technical Information of China (English)

    Long Jia; Yongfu Xu

    2011-01-01

    The formation of nitric acid hydrates has been observed in a chamber during the dark reaction of NO2 with O3 in the presence of air.The size of condensed phase nitric acid was measured to be 40-100 nm and 20-65 nm at relative humidity (RH) ≤ 5% and RH = 67% under our experimental conditions, respectively.The nitric acid particles were collected on the glass fiber membrane and their chemical compositions were analyzed by infrared spectrum.The main components of nitric acid hydrates in particles are HNO3·3H2O and NO3-·xH2O (x≥ 4) at low RH, whereas at high RH HNO3·H2O, HNO3·2H2O, HNO3·3H2O and NO3-·xH2O (x≥ 4) all exist in the condensed phase.At high RH HNO3·xH2O (x ≤ 3) collected on the glass fiber membrane is greatly increased, while NO3-·xH2O (x ≥4) decreased, compared with low RH.To the best of our knowledge, this is the first time to report that condensed phase nitric acid can be generated in the gas phase at room temperature.

  1. Modelling of steam condensation in the primary flow channel of a gas-heated steam generator

    International Nuclear Information System (INIS)

    Kawamura, H.; Meister, G.

    1982-10-01

    A new simulation code has been developed for the analysis of steam ingress accidents in high temperatures reactors which evaluates the heat transfer in a steam generator headed by a mixture of helium and water steam. Special emphasis is laid on the analysis of steam condensation in the primary circuit of the steam generator. The code takes wall and bulk condensation into account. A new method is proposed to describe the entrainment of water droplets in the primary gas flow. Some typical results are given. Steam condensation in the primary channel may have a significant effect on temperature distributions. The effect on the heat transferred by the steam generator, however, is found to be not so prominent as might be expected. The reason is discussed. A simplified code will also be described, which gives results with reasonable accuracy within much shorter execution times. This code may be used as a program module in a program simulating the total primary circuit of a high temperature reactor. (orig.) [de

  2. Effect of non-condensable gas on startup of a loop thermosyphon

    International Nuclear Information System (INIS)

    He, Jiang; Lin, Guiping; Bai, Lizhan; Miao, Jianyin; Zhang, Hongxing; Wang, Lu

    2013-01-01

    Non-condensable gas (NCG) generated inside two-phase heat transfer devices can adversely affect the thermal performance and limit the lifetime of such devices. In this work, experimental investigation of the effect of NCG on the startup of an ammonia-stainless steel loop thermosyphon was conducted. In the experiment, nitrogen was injected into the loop thermosyphon as NCG. The effect of NCG inventory on the startup behavior was investigated by adjusting the injected amount of nitrogen. The experimental results reveal that NCG prolongs the startup time and increases the startup liquid superheat and temperature overshoot; the more NCG exists in the loop thermosyphon, the higher the liquid superheat and temperature overshoot. When NCG is present in the system, boiling usually occurs in the evaporator before startup, but it does not mean the system will start up instantly, which differs from the conditions without NCG. Under all the conditions, increasing the heat load can effectively shorten the startup time but leads to a large temperature overshoot; forced convection cooling of the condenser has almost no effect on shortening the startup time especially for large NCG inventory situations, but it can effectively limit the temperature overshoot. For large NCG inventory situations, the loop thermosyphon can start up at a small heat load (5 W) or even without a heat load when the condenser is cooled by forced convection of ethanol. No failed start-ups occurred during any of the tests. (authors)

  3. Gas scavenging of insoluble vapors: Condensation of methyl salicylate vapor onto evaporating drops of water

    Science.gov (United States)

    Seaver, Mark; Peele, J. R.; Rubel, Glenn O.

    We have observed the evaporation of acoustically levitated water drops at 0 and 32% relative humidity in a moving gas stream which is nearly saturated with methyl salicylate vapor. The initial evaporation rate is characteristic of a pure water drop and gradually slows until the evaporation rate becomes that of pure methyl salicylate. The quantity of condensed methyl salicylate exceeds its Henry's law solubility in water by factors of more than 30-50. This apparent violation of Henry's law agrees with the concentration enhancements in the liquid phase found by glotfelty et al. (1987, Nature235, 602-605) during their field measurements of organophorus pesticides in fog water. Under our conditions, visual evidence demonstrates the presence of two liquid phases, thus invalidating the use of Henry's law. A continuum evaporation-condensation model for an immiscible two-component system which accounts for evaporative self-cooling of the drop correctly predicts the amount of methyl salicylate condensed onto the water drops.

  4. Feasibility study on the guided wave technique for condenser tube in NPP

    International Nuclear Information System (INIS)

    Choi, Sung Nam; Kim, Young Ho; Kim, Hyung Nam; Yoo, Hyun Joo; Hwang, W. G.

    2004-01-01

    The condenser tube is examined by the eddy current test (ECT) method to identify the integrity of the nuclear power plant. Because ECT probe is moved through the tube inside to identify flaws, the ECT probe should be exchanged periodically due to the wear of probe surface in order to remove the noise form the ECT signal. Moreover, it is impossible to examine the tube by ECT method because the ECT probe can not move through the inside due to the deformation such as dent. Recently, the theory of guided wave was established and the equipment applying the theory has been actively developed so as to overcome the limitation of ECT method for the tube inspection of heater exchanger in nuclear power plant. The object of this study is to know the feasibility of applying the guided wave technique to condenser tube in NPP

  5. Mixed convection heat transfer between a steam / non-condensable gas mixture and an inclined finned tube bundle

    Energy Technology Data Exchange (ETDEWEB)

    Cachard, F. de; Lomperski, S.; Monauni, G.R. [Paul Scherrer Inst. (PSI), Villigen (Switzerland). Lab. for Thermal-Hydraulics

    1999-07-01

    An experimental and analytical program was performed at PSI to study the performance of a finned-tube condenser in the presence of non-condensable gases at low gas mass fluxes. The model developed for this application includes mixed convection heat transfer between the vapour/non-condensable mixture and the finned-tubes, heat conduction through the fins and tubes, and evaporative heat transfer inside the tubes. The finned-tubes condenser model has been assessed against data obtained at the PSI LINX facility with two test condensers. For the 62 LINX experiments performed, the model predictions are very good, i.e., less than 10 % standard deviation between experimental and predicted results. (authors)

  6. Coherent Control of Multiphoton Transitions in the Gas and Condensed Phases with Shaped Ultrashort Pulses

    International Nuclear Information System (INIS)

    Dantus, Marcos

    2008-01-01

    Controlling laser-molecule interactions has become an integral part of developing devices and applications in spectroscopy, microscopy, optical switching, micromachining and photochemistry. Coherent control of multiphoton transitions could bring a significant improvement of these methods. In microscopy, multi-photon transitions are used to activate different contrast agents and suppress background fluorescence; coherent control could generate selective probe excitation. In photochemistry, different dissociative states are accessed through two, three, or more photon transitions; coherent control could be used to select the reaction pathway and therefore the yield-specific products. For micromachining and processing a wide variety of materials, femtosecond lasers are now used routinely. Understanding the interactions between the intense femtosecond pulse and the material could lead to technologically important advances. Pulse shaping could then be used to optimize the desired outcome. The scope of our research program is to develop robust and efficient strategies to control nonlinear laser-matter interactions using ultrashort shaped pulses in gas and condensed phases. Our systematic research has led to significant developments in a number of areas relevant to the AMO Physics group at DOE, among them: generation of ultrashort phase shaped pulses, coherent control and manipulation of quantum mechanical states in gas and condensed phases, behavior of isolated molecules under intense laser fields, behavior of condensed phase matter under intense laser field and implications on micromachining with ultrashort pulses, coherent control of nanoparticles their surface plasmon waves and their nonlinear optical behavior, and observation of coherent Coulomb explosion processes at 10 16 W/cm 2 . In all, the research has resulted in 36 publications (five journal covers) and nine invention disclosures, five of which have continued on to patenting

  7. Maximize Liquid Oil Production from Shale Oil and Gas Condensate Reservoirs by Cyclic Gas Injection

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, James [Texas Tech Univ., Lubbock, TX (United States); Li, Lei [Texas Tech Univ., Lubbock, TX (United States); Yu, Yang [Texas Tech Univ., Lubbock, TX (United States); Meng, Xingbang [Texas Tech Univ., Lubbock, TX (United States); Sharma, Sharanya [Texas Tech Univ., Lubbock, TX (United States); Huang, Siyuan [Texas Tech Univ., Lubbock, TX (United States); Shen, Ziqi [Texas Tech Univ., Lubbock, TX (United States); Zhang, Yao [Texas Tech Univ., Lubbock, TX (United States); Wang, Xiukun [Texas Tech Univ., Lubbock, TX (United States); Carey, Bill [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nguyen, Phong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Porter, Mark [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jimenez-Martinez, Joaquin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Viswanathan, Hari [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mody, Fersheed [Apache Corp., Houston, TX (United States); Barnes, Warren [Apache Corp., Houston, TX (United States); Cook, Tim [Apache Corp., Houston, TX (United States); Griffith, Paul [Apache Corp., Houston, TX (United States)

    2017-11-17

    The current technology to produce shale oil reservoirs is the primary depletion using fractured wells (generally horizontal wells). The oil recovery is less than 10%. The prize to enhance oil recovery (EOR) is big. Based on our earlier simulation study, huff-n-puff gas injection has the highest EOR potential. This project was to explore the potential extensively and from broader aspects. The huff-n-puff gas injection was compared with gas flooding, water huff-n-puff and waterflooding. The potential to mitigate liquid blockage was also studied and the gas huff-n-puff method was compared with other solvent methods. Field pilot tests were initiated but terminated owing to the low oil price and the operator’s budget cut. To meet the original project objectives, efforts were made to review existing and relevant field projects in shale and tight reservoirs. The fundamental flow in nanopores was also studied.

  8. NUMERICAL TECHNIQUES TO SOLVE CONDENSATIONAL AND DISSOLUTIONAL GROWTH EQUATIONS WHEN GROWTH IS COUPLED TO REVERSIBLE REACTIONS (R823186)

    Science.gov (United States)

    Noniterative, unconditionally stable numerical techniques for solving condensational anddissolutional growth equations are given. Growth solutions are compared to Gear-code solutions forthree cases when growth is coupled to reversible equilibrium chemistry. In all cases, ...

  9. Mixed convection heat transfer between a steam/non-condensable gas mixture and an inclined finned tube bundle

    Energy Technology Data Exchange (ETDEWEB)

    De Cachard, F.; Lompersky, S.; Monauni, G.R. [Paul Scherrer Institute, Villigen (Switzerland). Thermal Hydraulic Lab.

    1999-07-01

    An experimental and analytical program was performed at PSI (Paul Scherrer Institute) to study the performance of a finned-tube condenser in the presence of non-condensable gases at low gas mass fluxes. The model developed for this application includes mixed convection heat transfer between the vapour/non-condensable mixture and the finned tubes, heat conduction through the fins and tubes, and evaporative heat transfer inside the tubes. On the gas, heat transfer correlations are used, and the condensation rate is calculated using the heat/mass transfer analogy. A combination of various available correlations for forced convection in staggered finned tube bundles is used, together with a correction accounting for superimposed natural convection. For the condensate heat transfer resistance, the beatty and Katz model for gravity driven liquid films on the tubes is used. The fine efficiency is accounted for using classical iterative calculations. Evaporative heat transfer inside the tubes is predicted using the Chen correlation. The finned tube condenser model has been assessed against data obtained at the PSI LINX facility with two test condensers. For the 62 LINX experiments performed, the model predictions are very good, i.e., less then 10% standard deviation between experimental and predicted results.

  10. Investigation of Bose Condensation in Ideal Bose Gas Trapped under Generic Power Law Potential in d Dimension

    Science.gov (United States)

    Mehedi Faruk, Mir; Sazzad Hossain, Md.; Muktadir Rahman, Md.

    2016-02-01

    The changes in characteristics of Bose condensation of ideal Bose gas due to an external generic power law potential U=\\sumi=1dci\\vert xi/ai\\vertni are studied carefully. Detailed calculation of Kim et al. (J. Phys. Condens. Matter 11 (1999) 10269) yielded the hierarchy of condensation transitions with changing fractional dimensionality. In this manuscript, some theorems regarding specific heat at constant volume CV are presented. Careful examination of these theorems reveal the existence of hidden hierarchy of the condensation transition in trapped systems as well.

  11. Flue gas condensation in oxyfuel power plants. Heat- and mass transfer measurements and experimental validation of an efficient condensation concept; Rauchgaskondensation in Oxyfuel-Kraftwerken. Waerme- und Stoffuebergangsmessungen sowie experimentelle Validierung eines effizienten Kondensationskonzepts

    Energy Technology Data Exchange (ETDEWEB)

    Raindl, Markus

    2010-12-06

    Condensation of a steam-inert gas mixture in an Oxyfuel condenser differs significantly from condensation of pure steam: condenser pressure and rest gas content increase dramatically, heat- and mass transfer coefficients are lower and oversaturation of the steam-inert gas mixture yields to fog formation. In the context of this thesis, therefore, at first the optimal ranges of working parameters for Oxyfuel processes calculated. In the following some heat flux measurements were carried out on a horizontal, crossflow pipe to validate various heat- and mass transfer theories. Building on these results a new, efficient condensation concept was developed to reduce fog formation. The final results of the measurements with a laboratory model show great performance regarding fog reduction and condensation efficiency. (orig.)

  12. Azide-based cross-linking of polymers of intrinsic microporosity (PIMs) for condensable gas separation

    KAUST Repository

    Du, Naiying; Dal-Cin, Mauro M D; Pinnau, Ingo; Nicalek, Andrzej; Robertson, Gilles P.; Guiver, Michael D.

    2011-01-01

    Cross-linked polymers of intrinsic microporosity (PIM)s for gas separation membranes, were prepared by a nitrene reaction from a representative PIM in the presence of two different diazide cross-linkers. The reaction temperature was optimized using TGA. The homogenous membranes were cast from THF solutions of different ratios of PIM to azides. The resulting cross-linked structures of the PIMs membranes were formed at 175 °C after 7.5 h and confirmed by TGA, XPS, FT-IR spectroscopy and gel content analysis. These resulting cross-linked polymeric membranes showed excellent gas separation performance and can be used for O 2/N 2 and CO 2/N 2 gas pairs, as well as for condensable gases, such as CO 2/CH 4, propylene/propane separation. Most importantly, and differently from typical gas separation membranes derived from glassy polymers, the crosslinked PIMs showed no obvious CO 2 plasticization up to 20 atm pressure of pure CO 2 and CO 2/CH 4 mixtures. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Azide-based cross-linking of polymers of intrinsic microporosity (PIMs) for condensable gas separation

    KAUST Repository

    Du, Naiying

    2011-03-11

    Cross-linked polymers of intrinsic microporosity (PIM)s for gas separation membranes, were prepared by a nitrene reaction from a representative PIM in the presence of two different diazide cross-linkers. The reaction temperature was optimized using TGA. The homogenous membranes were cast from THF solutions of different ratios of PIM to azides. The resulting cross-linked structures of the PIMs membranes were formed at 175 °C after 7.5 h and confirmed by TGA, XPS, FT-IR spectroscopy and gel content analysis. These resulting cross-linked polymeric membranes showed excellent gas separation performance and can be used for O 2/N 2 and CO 2/N 2 gas pairs, as well as for condensable gases, such as CO 2/CH 4, propylene/propane separation. Most importantly, and differently from typical gas separation membranes derived from glassy polymers, the crosslinked PIMs showed no obvious CO 2 plasticization up to 20 atm pressure of pure CO 2 and CO 2/CH 4 mixtures. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. The Coupling Effect Research of Ash Deposition and Condensation in Low Temperature Flue Gas

    Directory of Open Access Journals (Sweden)

    Lei Ma

    2016-01-01

    Full Text Available Ash deposition is a key factor that deteriorates the heat transfer performance and leads to higher energy consumption of low pressure economizer working in low temperature flue gas. In order to study the ash deposition of heat exchange tubes in low temperature flue gas, two experiments are carried out with different types of heat exchange tubes in different flue gas environments. In this paper, Nusselt Number Nu and fouling factor ε are calculated to describe the heat transfer characteristics so as to study the ash deposition condition. The scanning electron microscope (SEM is used for the analysis of ash samples obtained from the outer wall of heat exchange tubes. The dynamic process of ash deposition is studied under different temperatures of outer wall. The results showed that ash deposition of heat exchanger will achieve a stable state in constant flue gas environment. According to the condition of condensation of acid vapor and water vapor, the process of ash deposition can be distinguished as mere ash deposition, acid-ash coupling deposition, and acid-water-ash coupling deposition.

  15. The stereochemistry of the condensation product of salicylaldehyde and n-butylbarbituric acid by NMR techniques

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Elizabete R.; Villar, J. Daniel Figueroa [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Quimica

    1995-12-31

    Since the discovery of the 5-deazaflavin cofactor (coenzyme F{sub 420}) as a naturally occurring compound, a great attention has been focused on several iso steric flavin analogues. One of the simplest approaches towards the synthesis of oxadeazaflavin, compound which the nitrogen at the N-10 position of 5-deazaflavin is replaced by oxygen, is the direct condensation between barbituric acid and salicylaldehyde. In this paper, the use of some NMR techniques so as to determine the stereochemistry of the preformed isomer has been described and a possible mechanism for this isomerization discussed 12 refs., 2 figs., 1 tab.

  16. The stereochemistry of the condensation product of salicylaldehyde and n-butylbarbituric acid by NMR techniques

    International Nuclear Information System (INIS)

    Cruz, Elizabete R.; Villar, J. Daniel Figueroa

    1995-01-01

    Since the discovery of the 5-deazaflavin cofactor (coenzyme F 420 ) as a naturally occurring compound, a great attention has been focused on several iso steric flavin analogues. One of the simplest approaches towards the synthesis of oxadeazaflavin, compound which the nitrogen at the N-10 position of 5-deazaflavin is replaced by oxygen, is the direct condensation between barbituric acid and salicylaldehyde. In this paper, the use of some NMR techniques so as to determine the stereochemistry of the preformed isomer has been described and a possible mechanism for this isomerization discussed

  17. Colloidal gas-liquid condensation of polystyrene latex particles with intermediate kappa a values (5 to 160, a > kappa(-1)).

    Science.gov (United States)

    Ishikawa, Masamichi; Kitano, Ryota

    2010-02-16

    Polystyrene latex particles showed gas-liquid condensation under the conditions of large particle radius (a > kappa(-1)) and intermediate kappa a, where kappa is the Debye-Hückel parameter and a is the particle radius. The particles were dissolved in deionized water containing ethanol from 0 to 77 vol %, settled to the bottom of the glass plate within 1 h, and then laterally moved toward the center of a cell over a 20 h period in reaching a state of equilibrium condensation. All of the suspensions that were 1 and 3 microm in diameter and 0.01-0.20 vol % in concentration realized similar gas-liquid condensation with clear gas-liquid boundaries. In 50 vol % ethanol solvent, additional ethanol was added to enhance the sedimentation force so as to restrict the particles in a monoparticle layer thickness. The coexistence of gas-liquid-solid (crystalline solid) was microscopically recognized from the periphery to the center of the condensates. A phase diagram of the gas-liquid condensation was created as a function of KCl concentration at a particle diameter of 3 microm, 0.10 vol % concentration, and 50:50 water/ethanol solvent at room temperature. The miscibility gap was observed in the concentration range from 1 to 250 microM. There was an upper limit of salt concentration where the phase separation disappeared, showing nearly critical behavior of macroscopic density fluctuation from 250 microM to 1 mM. These results add new experimental evidence to the existence of colloidal gas-liquid condensation and specify conditions of like-charge attraction between particles.

  18. Laboratory optimization tests of technetium decontamination of Hanford Waste Treatment Plant low activity waste melter off-gas condensate simulant

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M.L. [Savannah River Site (SRS), Aiken, SC (United States); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-11-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable simplified operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste.

  19. Condensing gas boilers for energy efficiency and reduction of CO2 and NOx

    International Nuclear Information System (INIS)

    Stewardson, E.

    1994-01-01

    The objectives of the study are: 1) to demonstrate the effectiveness of condensing gas boiler hot water system in reducing energy costs and pollution; 2) to illustrate the importance of marketing this technology to uninformed end users. The development of condensing boilers in the European Community, the materials used, product designs, key performance measures, and the types of applications suited to these products are outlined. Using calculations from a body of work produced by the Chartered Institute of Building Service Engineers in Britain, it is demonstrated how seasonal efficiency differs from combustion efficiency, and how the added capital cost for these boilers may be recovered within an acceptable commercial pay back period from fuel cost savings. Applying current NO x and CO 2 information from a body of the CE Technical Committees, the author show how these products can reduce pollution levels both from CO 2 and NO x . An example of marketing these products to a largely uninformed end user customer market is cited. 2 refs., 3 tabs., 12 figs. (orig.)

  20. Effect of non-condensable gas on steady-state operation of a loop thermosyphon

    International Nuclear Information System (INIS)

    He, Jiang; Lin, Guiping; Bai, Lizhan; Miao, Jianyin; Zhang, Hongxing; Wang, Lu

    2014-01-01

    Non-condensable gas (NCG) generated inside two-phase heat transfer devices can adversely affect the thermal performance and limit the lifetime of such devices. In this work, extensive experimental investigation of the effect of NCG on the steady-state operation of an ammonia-stainless steel loop thermosyphon was conducted. In the experiments, nitrogen was injected into the loop thermosyphon as NCG, and the thermal performance of the loop thermosyphon was tested at different NCG inventories, heat loads applied to the evaporator and condenser cooling conditions, i.e. natural air cooling or circulating ethanol cooling. Experimental results reveal that NCG elevates the steady-state operating temperature of the evaporator, especially when the loop thermosyphon is operating in the low temperature range; meanwhile, the more NCG exists in the loop thermosyphon, the higher the operating temperature of the evaporator, and the lower the reservoir temperature. In addition, the existence of NCG results in the decrease of the overall thermal conductance of the loop thermosyphon, and the overall thermal conductance under the ethanol cooling condition may be even lower than that under the air cooling condition when the heat load is smaller than a certain value. Finally, the experimental results are theoretically analysed and explained. (authors)

  1. Gas chromatographic determination of residual hydrazine and morpholine in boiler feed water and steam condensates

    International Nuclear Information System (INIS)

    Vatsala, S.; Bansal, V.; Tuli, D.K.; Rai, M.M.; Jain, S.K.; Srivastava, S.P.; Bhatnagar, A.K.

    1994-01-01

    Hydrazine, an oxygen scavenger in boiler water, was derivatised to the corresponding acetone azine and determined at the ng ml -1 level by gas chromatography. Morpholine, a corrosion inhibitor used in steam boilers, was estimated either directly (if >2.0 μg ml -1 ) or by quantitative preconcentration (0.1 ng-2.0 μg ml -1 ). To obtain symmetrical peaks for these amines, the column packing was coated with KOH. Use of a nitrogen-specific detector improved accuracy of estimation of hydrazine and morpholine, giving a RSD of 1.9-3.6%. Chromatographic analysis of these amines in boiler feed water and steam condensate samples collected from boilers servicing a pertroleum refinery is described. Environmental safety regulations calls for monitoring of hydrazine and the methods developed can easily be adapted for this purpose. (orig.)

  2. Aspects of hyperspherical adiabaticity in an atomic-gas Bose-Einstein condensate

    International Nuclear Information System (INIS)

    Kushibe, Daisuke; Mutou, Masaki; Morishita, Toru; Watanabe, Shinichi; Matsuzawa, Michio

    2004-01-01

    Excitation of an atomic-gas Bose-Einstein condensate (BEC) in the zeroth-order ground-state channel is studied with the hyperspherical adiabatic method of Bohn et al. [Bohn et al., Phys. Rev. A 58, 584 (1998)] suitably generalized to accommodate the anisotropic trapping potential. The method exploits the system's size as an adiabatic parameter so that the explicit size dependence is immediately conducive to the virial theorem. The oscillation frequencies associated with the monopole (breathing) and quadrupole modes thus emerge naturally and converge to the well-known Thomas-Fermi limits. Analysis of the single-particle density and the projected excitation wave function shows that the excitation in the single hyperspherical ground-state channel merely represents a progressive increase in occupancy of the first excited single-particle state. The work paves the way for applying the adiabatic picture to other BEC phenomena

  3. Numerical Method based on SIMPLE Algorithm for a Two-Phase Flow with Non-condensable Gas

    International Nuclear Information System (INIS)

    Kim, Jong Tae

    2009-08-01

    In this study, a numerical method based on SIMPLE algorithm for a two-phase flow with non-condensable gas has been developed in order to simulate thermal hydraulics in a containment of a nuclear power plant. As governing equations, it adopts a two-fluid three-field model for the two-phase flows. The three fields include gas, drops, and continuous liquid. The gas field can contains vapor and non-condensable gases such as air and hydrogen. In order to resolve mixing phenomena of gas species, gas transport equations for each species base on the gas mass fractions are solved with gas phase governing equations such as mass, momentum and energy equations. Methods to evaluate the properties of the gas species were implemented in the code. They are constant or polynomial function based a user input and a property library from Chemkin and JANAF table for gas specific heat. Properties for the gas mixture which are dependent on mole fractions of the gas species were evaluated by a mix rule

  4. Preparation of development plan for the gas-condensate pool with the use of a high speed computer (IBM-1620)

    Energy Technology Data Exchange (ETDEWEB)

    Shirkovsky, A I; Kumar, S

    1968-01-01

    The computation of all the technical, technological, and economic figures for a gas supply system by using the High Speed Computer IBM-1620 is presented. The gas supply system consists of a gas-condensate pool (source) and main gas pipeline from the pool to the consumer. All necessary analytical equations for correlating geological, technological, and economic variables have been used. Results of calculations and recommendations for the most profitable variant are given. Effects of geological, technological, and technical factors upon the economic figures are also shown.

  5. OPTIMAL SYSNTHESIS PROCESSES OF LOW-TEMPERATURE CONDENSATION ASSOCIATED OIL GAS PLANT REFRIGERATION SYSTEM

    Directory of Open Access Journals (Sweden)

    O. Ostapenko

    2015-10-01

    Full Text Available Design of modern high-efficient systems is a key priority for the Energy Sector of Ukraine. The cooling technological streams of gas and oil refineries, including air coolers, water cooling and refrigeration systems for specific refrigerants are the objectives of the present study. Improvement of the refrigeration unit with refrigerant separation into fractions is mandatory in order to increase cooling capacity, lowering the boiling point of coolant and increasing the coefficient of target hydrocarbons extraction from the associated gas flow. In this paper it is shown that cooling temperature plays significant role in low-temperature condensation process. Two operation modes for refrigeration unit were proposed: permanent, in which the concentration of the refrigerant mixture does not change and dynamic, in which the concentration of refrigerant mixtures depends on the ambient temperature. Based on the analysis of exergy losses the optimal concentration of refrigerant mixtures propane/ethane for both modes of operation of the refrigeration unit has been determined. On the basis of the conducted pinch-analysis the modification of refrigeration unit with refrigerant separation into fractions was developed. Additional recuperative heat exchangers for utilization heat were added to the scheme. Several important measures to increase the mass flow rate of refrigerant through the second section of the refrigeration centrifugal compressor from 22.5 to 25 kg/s without violating the agreed operational mode of the compressor sections were implemented.

  6. Intrinsic bioremediation of petroleum hydrocarbons in a gas condensate-contaminated aquifer

    International Nuclear Information System (INIS)

    Gieg, L.M.; McInerney; Tanner, R.S.; Harris, S.H. Jr.; Sublette, K.L.; Suflita, J.M.; Kolhatkar, R.V.

    1999-01-01

    A study was designed to determine if the intrinsic bioremediation of gas condensate hydrocarbons represented an important fate process in a shallow aquifer underlying a natural gas production site. For over 4 yr, changes in the groundwater, sediment, and vadose zone chemistry in the contaminated portion of the aquifer were interpreted relative to a background zone. Changes included decreased dissolved oxygen and sulfate levels and increased alkalinity, Fe(II), and methane concentrations in the contaminated groundwater, suggesting that aerobic heterotrophic respiration depleted oxygen reserves leaving anaerobic conditions in the hydrocarbon-impacted subsurface. Dissolved hydrogen levels in the contaminated groundwater indicated that sulfate reduction and methanogenesis were predominant biological processes, corroborating the geochemical findings. Furthermore, 10--1000-fold higher numbers of sulfate reducers and methanogens were enumerated in the contaminated sediment relative to background. Putative metabolites were also detected in the contaminated groundwater, including methylbenzylsuccinic acid, a signature intermediate of anaerobic xylene decay. Laboratory incubations showed that benzene, toluene, ethylbenzene, and each of the xylene isomers were biodegraded under sulfate-reducing conditions as was toluene under methanogenic conditions. These results coupled with a decrease in hydrocarbon concentrations in contaminated sediment confirm that intrinsic bioremediation contributes to the attenuation of hydrocarbons in this aquifer

  7. Steam condenser

    International Nuclear Information System (INIS)

    Masuda, Fujio

    1980-01-01

    Purpose: To enable safe steam condensation by providing steam condensation blades at the end of a pipe. Constitution: When high temperature high pressure steam flows into a vent pipe having an opening under water in a pool or an exhaust pipe or the like for a main steam eacape safety valve, non-condensable gas filled beforehand in the steam exhaust pipe is compressed, and discharged into the water in the pool. The non-condensable gas thus discharged from the steam exhaust pipe is introduced into the interior of the hollow steam condensing blades, is then suitably expanded, and thereafter exhausted from a number of exhaust holes into the water in the pool. In this manner, the non-condensable gas thus discharged is not directly introduced into the water in the pool, but is suitable expanded in the space of the steam condensing blades to suppress extreme over-compression and over-expansion of the gas so as to prevent unstable pressure vibration. (Yoshihara, H.)

  8. Studies of cluster-assembled materials: From gas phase to condensed phase

    Science.gov (United States)

    Gao, Lin

    . After being mass gated in a reflectron equipped time-of-flight mass spectrometer (TOF-MS) and deposited onto TEM grids, the resultant specimens can be loaded onto high-resolution TEM investigation via electron diffraction. In conclusion, soft-landing of mass selected clusters has been shown to be a successful approach to obtain structural information on Zr-Met-Car cluster-assembled materials collected from the gas phase. TEM images indicate the richness of the morphologies associated with these cluster crystals. However, passivation methods are expected to be examined further to overcome the limited stabilities of these novel clusters. From this initial study, it's shown the promising opportunity to study other Met-Cars species and more cluster-based materials. Experimental results of reactions run with a solvothermal synthesis method obtained while searching for new Zr-C cluster assembled materials, are reported. One unexpected product in single crystal form was isolated and tentatively identified by X-ray diffraction to be [Zr6i O(OH)O12·2(Bu)4], with space group P2 1/n and lattice parameters of a = 12.44 A, b = 22.06 A, c = 18.40 A, alpha = 90°, beta = 105°, gamma = 90°, V = 4875 A3 and R 1 = 3.15% for the total observed data (I ≥ 2 sigma I) and oR2 = 2.82%. This novel hexanuclear Zr(IV)-oxo-hydroxide cluster anion may be the first member in polyoxometalates class with metal atoms from the IVB group and having Oh symmetry. Alternatively, it may be the first member in {[(Zr6Z)X 12]X6}m- class with halides replaced by oxo- and hydroxyl groups and with an increased oxidation state of Zr. It is predicted to bear application potentials directed by both families. This work could suggest a direction in which the preparation of Zr-C cluster-assembled materials in a liquid environment may be eventually fulfilled. 1,3-Bis(diethylphosphino)propane (depp) protected small gold clusters are studied via multiple techniques, including Electrospray Ionization Mass Spectrometry

  9. Interstellar silicate analogs for grain-surface reaction experiments: Gas-phase condensation and characterization of the silicate dust grains

    Energy Technology Data Exchange (ETDEWEB)

    Sabri, T.; Jäger, C. [Laboratory Astrophysics Group of the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena Institute of Solid State Physics, Helmholtzweg 3, D-07743 Jena (Germany); Gavilan, L.; Lemaire, J. L.; Vidali, G. [Observatoire de Paris/Université de Cergy-Pontoise, 5 mail Gay Lussac, F-95000 Cergy-Pontoise (France); Mutschke, H. [Laboratory Astrophysics Group of the Astrophysical Institute and University Observatory, Friedrich Schiller University Jena Schillergässchen 3, D-07743 Jena (Germany); Henning, T., E-mail: tolou.sabri@uni-jena.de [Max Planck Institute for Astronomy Königstuhl 17, D-69117 Heidelberg (Germany)

    2014-01-10

    Amorphous, astrophysically relevant silicates were prepared by laser ablation of siliceous targets and subsequent quenching of the evaporated atoms and clusters in a helium/oxygen gas atmosphere. The described gas-phase condensation method can be used to synthesize homogeneous and astrophysically relevant silicates with different compositions ranging from nonstoichiometric magnesium iron silicates to pyroxene- and olivine-type stoichiometry. Analytical tools have been used to characterize the morphology, composition, and spectral properties of the condensates. The nanometer-sized silicate condensates represent a new family of cosmic dust analogs that can generally be used for laboratory studies of cosmic processes related to condensation, processing, and destruction of cosmic dust in different astrophysical environments. The well-characterized silicates comprising amorphous Mg{sub 2}SiO{sub 4} and Fe{sub 2}SiO{sub 4}, as well as the corresponding crystalline silicates forsterite and fayalite, produced by thermal annealing of the amorphous condensates, have been used as real grain surfaces for H{sub 2} formation experiments. A specifically developed ultra-high vacuum apparatus has been used for the investigation of molecule formation experiments. The results of these molecular formation experiments on differently structured Mg{sub 2}SiO{sub 4} and Fe{sub 2}SiO{sub 4} described in this paper will be the topic of the next paper of this series.

  10. An investigation of condensation from steam-gas mixtures flowing downward inside a vertical tube

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, S.Z.; Schrock, V.E.; Peterson, P.F. [Univ. of California, Berkeley, CA (United States)

    1995-09-01

    Previous experiments have been carried out by Vierow, Ogg, Kageyama and Siddique for condensation from steam/gas mixtures in vertical tubes. In each case the data scatter relative to the correlation was large and there was not close agreement among the three investigations. A new apparatus has been designed and built using the lessons learned from the earlier studies. Using the new apparatus, an extensive new data base has been obtained for pure steam, steam-air mixtures and steam-helium mixtures. Three different correlations, one implementing the degradation method initially proposed by Vierow and Schrock, a second diffusion layer theory initially proposed by Peterson, and third mass transfer conductance model are presented in this paper. The correlation using the simple degradation factor method has been shown, with some modification, to give satisfactory engineering accuracy when applied to the new data. However, this method is based on very simplified arguments that do not fully represent the complex physical phenomena involved. Better representation of the data has been found possible using modifications of the more complex and phenomenologically based method which treats the heat transfer conductance of the liquid film in series with the conductance on the vapor-gas side with the latter comprised of mass transfer and sensible heat transfer conductance acting in parallel. The mechanistic models, based on the modified diffusion layer theory or classical mass transfer theory for mass transfer conductance with transpiration successfully correlate the data for the heat transfer of vapor-gas side. Combined with the heat transfer of liquid film model proposed by Blangetti, the overall heat transfer coefficients predicted by the correlations from mechanistic models are in close agreement with experimental values.

  11. Evaluation of the condensation potential of hydrocarbon fluids in the national gas pipeline system; establishing of adequate operational schemes

    International Nuclear Information System (INIS)

    Pineda Gomez, Cesar Augusto; Arenas Mantilla, Oscar Armando; Santos Santos, Nicolas

    2007-01-01

    For transporting industry of natural gas by pipeline systems, it's vital to guarantee the integrity of their lines, in order to decrease operational costs and prevent accidents that may damaging against people's safety, the environment or the infrastructure itself. in this paper it's presented the principal compounds from o technical study about principal net and its distribution branches to municipalities of the National System Transport of Natural Gas pointed by the Colombian Natural Gas Company - ECOGAS, (specifically the Cusiana - Porvenir - La Belleza, La Belleza - Cogua, La Belleza - Vasconia, Vasconia - Neiva and Vasconia - Cali gas lines, (see Figure 1). The principal objective is evaluate the possible condensation of hydrocarbons fluids inside gas lines, due to compositional characteristics of the gas, the different topographical conditions along the gas line route and the actual and future operational conditions to be implemented in the system. The evaluation performed over this gas streams, generates transcendental information in the creation of safe operational limits that minimizing the existence of obstacle problems and damages over pipeline systems and process equipment, due to the presence of liquid hydrocarbons inside these flow lines. This article has been prepared in four sections in order to guarantee easy access to each one of the steps involved in the study. Section one presents the compositional and thermodynamic analysis of feeding gas streams; in section two, its presented the required information for modeling gas lines with definition of the gas pipeline numerical simulation model in stable state; section three presents the sensitivity analysis for gas variation upon loading gas composition at the inlet point of the system, variation of the operational conditions (flow, pressure and gas temperature) and environment temperatures for the different inlet points (branches) with verification of compliance of the Unique Transport Regulation

  12. Secondary ions produced from condensed rare gas targets under highly charged MeV/amu heavy ion bombardment

    International Nuclear Information System (INIS)

    Tawara, H.; Tonuma, T.; Kumagai, H.; Matsuo, T.

    1994-01-01

    Secondary ions produced from condensed rare gas targets are observed under MeV/amu, highly charged, heavy ion impact. The intensities of the observed cluster ions decrease smoothly as the cluster sizes become large but show some discontinuities at particular sizes of cluster ions. This seems to be closely related to the stabilities of cluster ion structures. It is also noted that very few doubly charged or practically no triply/higher charged ions have been observed, in sharp contrast to that of some condensed molecular targets. (orig.)

  13. A thermodynamic approach on vapor-condensation of corrosive salts from flue gas on boiler tubes in waste incinerators

    International Nuclear Information System (INIS)

    Otsuka, Nobuo

    2008-01-01

    Thermodynamic equilibrium calculation was conducted to understand the effects of tube wall temperature, flue gas temperature, and waste chemistry on the type and amount of vapor-condensed 'corrosive' salts from flue gas on superheater and waterwall tubes in waste incinerators. The amount of vapor-condensed compounds from flue gases at 650-950 deg. C on tube walls at 350-850 deg. C was calculated, upon combustion of 100 g waste with 1.6 stoichiometry (in terms of the air-fuel ratio). Flue gas temperature, rather than tube wall temperature, influenced the deposit chemistry of boiler tubes significantly. Chlorine, sulfur, sodium, potassium, and calcium contents in waste affected it as well

  14. Geochemical Study of Natural Bitumen, Condensate and Gas Seeps from Sousse Area, Central Tunisia

    OpenAIRE

    A. Belhaj Mohamed; M. Saidi; N. Boucherb; N. Ourtani; A. Soltani; I. Bouazizi; M. Ben Jrad

    2015-01-01

    Natural hydrocarbon seepage has helped petroleum exploration as a direct indicator of gas and/or oil subsurface accumulations. Surface macro-seeps are generally an indication of a fault in an active Petroleum Seepage System belonging to a Total Petroleum System. This paper describes a case study in which multiple analytical techniques were used to identify and characterize trace petroleum-related hydrocarbons and other volatile organic compounds in groundwater samples col...

  15. Fuzzy logic prediction of dew point pressure of selected Iranian gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Nowroozi, Saeed [Shahid Bahonar Univ. of Kerman (Iran); Iranian Offshore Oil Company (I.O.O.C.) (Iran); Ranjbar, Mohammad; Hashemipour, Hassan; Schaffie, Mahin [Shahid Bahonar Univ. of Kerman (Iran)

    2009-12-15

    The experimental determination of dew point pressure in a window PVT cell is often difficult especially in the case of lean retrograde gas condensate. Besides all statistical, graphical and experimental methods, the fuzzy logic method can be useful and more reliable for estimation of reservoir properties. Fuzzy logic can overcome uncertainty existent in many reservoir properties. Complexity, non-linearity and vagueness are some reservoir parameter characteristics, which can be propagated simply by fuzzy logic. The fuzzy logic dew point pressure modeling system used in this study is a multi input single output (MISO) Mamdani system. The model was developed using experimentally constant volume depletion (CVD) measured samples of some Iranian fields. The performance of the model is compared against the performance of some of the most accurate and general correlations for dew point pressure calculation. Results show that this novel method is more accurate and reliable with an average absolute deviation of 1.33% and 2.68% for developing and checking, respectively. (orig.)

  16. Production of Au clusters by plasma gas condensation and their incorporation in oxide matrixes by sputtering

    Science.gov (United States)

    Figueiredo, N. M.; Serra, R.; Manninen, N. K.; Cavaleiro, A.

    2018-05-01

    Gold clusters were produced by plasma gas condensation method and studied in great detail for the first time. The influence of argon flow, discharge power applied to the Au target and aggregation chamber length on the size distribution and deposition rate of Au clusters was evaluated. Au clusters with sizes between 5 and 65 nm were deposited with varying deposition rates and size dispersion curves. Nanocomposite Au-TiO2 and Au-Al2O3 coatings were then deposited by alternating sputtering. These coatings were hydrophobic and showed strong colorations due to the surface plasmon resonance effect. By simulating the optical properties of the nanocomposites it was possible to identify each individual contribution to the overall surface plasmon resonance signal. These coatings show great potential to be used as high performance localized surface plasmon resonance sensors or as robust self-cleaning decorative protective layers. The hybrid method used for depositing the nanocomposites offers several advantages over co-sputtering or thermal evaporation processes, since a broader range of particle sizes can be obtained (up to tens of nanometers) without the application of any thermal annealing treatments and the properties of clusters and matrix can be controlled separately.

  17. Decoupling damage mechanisms in acid-fractured gas/condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, R.C.; Walters, D.A. [Taurus Reservoir Solutions Ltd., Calgary, AB (Canada); Settari, A. [Calgary Univ., AB (Canada); Rahim, Z.; Ahmed, M.S. [Saudi Aramco, Dhahran (Saudi Arabia)

    2006-07-01

    The Khuff is a gas condensate field located 11,500 feet beneath the producing Ghawar oil field in Saudi Arabia. Wells are mainly acid fracture stimulated following drilling with excellent fracture conductivity and length properties. The wells experience a quick production loss however, after tie-in which eventually stabilizes after two to five months. In order to identify the source of productivity loss, such as near well liquid dropout, fracture conductivity loss, reservoir permeability loss due to increased effective stress, a study of a well in the Khuff field was conducted. The study reviewed basic geomechanical and reservoir properties and identified the mechanisms of production loss. The paper presented the methodology, data and preliminary analysis, relative permeability and results of the history matching. It was concluded that traditional production type curves in cases with changing skin may indicate that transient flow is occurring when boundary effects are felt. In addition, stress dependent fracture conductivity and reservoir permeability can be modeled with simpler pressure dependent functions for relatively low overall loss in reservoir pressure. 30 refs., 25 figs., 1 appendix.

  18. Studies on the characteristics of the separated heat pipe system with non-condensible gas for the use of the passive decay heat removal in reactor systems

    International Nuclear Information System (INIS)

    Hayashi, Takao; Ishi, Takayuki; Hayakawa, Hitoshi; Ohashi, Kazutaka

    1997-01-01

    Experiments on the separated heat pipe system of variable conductance type, which enclose non-condensible gas, have been carried out with intention of applying such system to passive decay heat removal of the modular reactors such as HTR plant. Basic experiments have been carried out on the experimental apparatus consisting of evaporator, vapor transfer tube, condenser tube and return tube which returns the condensed liquid back to the evaporator. Water and methanol were examined as the working fluids and nitrogen gas was enclosed as the non-condensible gas. The behaviors of the system were examined for the parametric changes of the heat input under the various pressures of nitrogen gas initially enclosed, including the case without enclosing N 2 gas for the comparison. The results of the experiments shows very clear features of self control characteristics. The self control mechanism was made clear, that is, in such system in which the condensing area in the condenser expands automatically in accordance with the increase of the heat input to keep the system temperature nearly constant. The working temperature of the system are clearly dependent on the pressure of the non-condensable gas initially enclosed, with higher system working temperature with higher initial gas pressure enclosed. The analyses were done on water and methanol as the working fluids, which show very good agreement with the experimental results. A lot of attractive applications are expected including the self switching feature with minimum heat loss during normal operation with maintaining the sufficient heat removal at accidents. (author)

  19. Developing of two-dimensional model of the corium cooling and behavior with non-condensible gas injection

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Chang Hyun; Cho, Jae Seon; Kim, Ju Youl; Kim, Do Hyoung [Seoul National University, Seoul (Korea, Republic of)

    1997-07-01

    The purpose of this study is to understand the effect of the non-condensible gas injection into the molten corium on the heat transfer and dynamic behavior within the melt when molten core-concrete interaction occurs during the hypothetical severe accident. Corium behavior with gas injection effect is two phase fluid pattern in which droplet has dispersed gas phase in continuous liquid phase of corium. To analyze this behavior, two dimensional governing equation using the governing equation, the computer program is accomplished using the finite difference method and SIMPLER algorithm. And benchmarking calculation is performed for the KfK experiment, which consider the gas injection effect. After this pre-calculation, an analyses is performed with typical corium under severe accidents. It is concluded that the heat transfer within corium increases as the metal components of the corium and gas injection velocity increase. 88 refs., 23 tabs., 35 figs. (author)

  20. Correcting underestimation of optimal fracture length by modeling proppant conductivity variations in hydraulically fractured gas/condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Akram, A.H.; Samad, A. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Schlumberger, Houston, TX (United States)

    2006-07-01

    A study was conducted in which a newly developed numerical simulator was used to forecast the productivity of a hydraulically fractured well in a retrograde gas-condensate sandstone reservoir. The effect of condensate dropout was modeled in both the reservoir and the proppant pack. The type of proppant and the stress applied to it are among the factors that determine proppant conductivity in a single-phase flow. Other factors include the high velocity of gas and the presence of liquid in the proppant pack. It was concluded that apparent proppant permeability in a gas condensate reservoir varies along the length of the hydraulic fracture and depends on the distance from the wellbore. It will increase towards the tip of the fracture where liquid ratio and velocity are lower. Apparent proppant permeability also changes with time. Forecasting is most accurate when these conditions are considered in the simulation. There are 2 problems associated with the use of a constant proppant permeability in a gas condensate reservoir. The first relates to the fact that it is impossible to obtain a correct single number that will mimic the drawdown of the real fracture at a particular rate without going through the process of determining the proppant permeability profile in a numerical simulator. The second problem relates to the fact that constant proppant permeability yields an optimal fracture length that is too short. Analytical modeling does not account for these complexities. It was determined that the only way to accurately simulate the behaviour of a hydraulic fracture in a high rate well, is by advanced numerical modeling that considers varying apparent proppant permeability in terms of time and distance along the fracture length. 10 refs., 2 tabs., 16 figs., 1 appendix.

  1. Non-linear optical techniques and optical properties of condensed molecular systems

    Science.gov (United States)

    Citroni, Margherita

    2013-06-01

    Structure, dynamics, and optical properties of molecular systems can be largely modified by the applied pressure, with remarkable consequences on their chemical stability. Several examples of selective reactions yielding technologically attractive products can be cited, which are particularly efficient when photochemical effects are exploited in conjunction with the structural conditions attained at high density. Non-linear optical techniques are a basic tool to unveil key aspects of the chemical reactivity and dynamic properties of molecules. Their application to high-pressure samples is experimentally challenging, mainly because of the small sample dimensions and of the non-linear effects generated in the anvil materials. In this talk I will present results on the electronic spectra of several aromatic crystals obtained through two-photon induced fluorescence and two-photon excitation profiles measured as a function of pressure (typically up to about 25 GPa), and discuss the relationship between the pressure-induced modifications of the electronic structure and the chemical reactivity at high pressure. I will also present the first successful pump-probe infrared measurement performed as a function of pressure on a condensed molecular system. The system under examination is liquid water, in a sapphire anvil cell, up to 1 GPa along isotherms at 298 and 363 K. These measurements give a new enlightening insight into the dynamical properties of low- and high-density water allowing a definition of the two structures.

  2. Development of a neural fuzzy system for advanced prediction of dew point pressure in gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Nowroozi, Saeed; Hashemipour, Hasan; Schaffie, Mahin [Department of Chemical Engineering, Shahid Bahonar University of Kerman (Iran); ERC, Shahid Bahonar University of Kerman (Iran); Ranjbar, Mohammad [Department of Mining Engineering, Shahid Bahonar University of Kerman (Iran); ERC, Shahid Bahonar University of Kerman (Iran)

    2009-03-15

    Dew point pressure is one of the most critical quantities for characterizing a gas condensate reservoir. So, accurate determination of this property has been the main challenge in reservoir development and management. The experimental determination of dew point pressure in PVT cell is often difficult especially in case of lean retrograde gas condensate. Empirical correlations and some equations of state can be used to calculate reservoir fluid properties. Empirical correlations do not have ability to reliable duplicate the temperature behavior of constant composition fluids. Equations of state have convergence problem and need to be tuned against some experimental data. Complexity, non-linearity and vagueness are some reservoir parameter characteristic which can be propagated simply by intelligent system. With the advantage of fuzzy sets in knowledge representation and the high capacity of neural nets (NNs) in learning knowledge expressed in data, in this paper a neural fuzzy system(NFS) is proposed to predict dew point pressure of gas condensate reservoir. The model was developed using 110 measurements of dew point pressure. The performance of the model is compared against performance of some of the most accurate and general correlations for dew point pressure calculation. From the results of this study, it can be pointed out that this novel method is more accurate and reliable with the mean square error of 0.058%, 0.074% and 0.044% for training, validation and test processes, respectively. (author)

  3. Hydrocarbons in sediments adjacent to a gas and condensate development and production platform in northwestern Australia

    International Nuclear Information System (INIS)

    Fischer, S.J.; Alexander, R.; Kagi, R.I.

    1994-01-01

    In northwestern Australia during the period of 1983 to 1991, 23 wells were drilled from a gas/condensate production platform to the producing formation approximately 3000 m below the sea bed. Low toxicity water-based drilling muds formulated with hydrogenated kerosenes were used, with the resultant formation cuttings being legally discharged into the ocean. To study the fate of hydrocarbons associated with the cuttings, sea-floor samples were collected along two perpendicular transects from the platform. The first extended 10 km in the prevailing direction of the current and the other to 1.2 km. Subsequently, samples have been collected from one of these sites on two occasions, first one year and secondly two years after the initial collection. Samples collected from directly under the platform cuttings chute contained the highest hydrocarbon concentrations, determined gravimetrically, of 75000 mg/kg, decreasing to approximately 40 mg/kg within 800 m in the direction of the prevailing current. Concentrations in the more remote samples were determined by GC and decreased gradually to be barely discernible above background at less than 0.01 mg/kg at 10 km from the platform. This suite of samples provided an excellent opportunity to study the progress of hydrocarbon biodegradation as it occurs in the marine environment. Analysis by GC-FID, GC-MS and GC-FTIR revealed a number of features. For example, the extent of biodegradation and weathering with increasing distance from the platform, and the half life for biodegradation of total hydrocarbons appears to be approximately one year. The hydrocarbon components of the sediments are mainly from the drilling mud with minor contributions from the formation fluids

  4. GASCON and MHDGAS: FORTRAN IV computer codes for calculating gas and condensed-phase compositions in the coal-fired open-cycle MHD system

    Energy Technology Data Exchange (ETDEWEB)

    Blackburn, P E

    1977-12-01

    Fortran IV computer codes have been written to calculate the equilibrium partial pressures of the gaseous phase and the quantity and composition of the condensed phases in the open-cycle MHD system. The codes are based on temperature-dependent equilibrium constants, mass conservation, the mass action law, and assumed ideal solution of compounds in each of two condensed phases. It is assumed that the phases are an oxide-silicate phase and a sulfate-carbonate-hydroxide phase. Calculations are iterated for gas and condensate concentrations while increasing or decreasing the total moles of elements, but keeping mole ratios constant, to achieve the desired total pressure. During iteration the oxygen partial pressure is incrementally changed. The decision to increase or decrease the oxygen pressure in this process depends on comparison of the oxygen content calculated in the gas and condensate phases with the initial amount of oxygen in the ash, coal, seed, and air. This process, together with a normalization step, allows the elements to converge to their initial quantities. Two versions of the computer code have been written. GASCON calculates the equilibrium gas partial pressures and the quantity and composition of the condensed phases in steps of thirteen temperature and pressure combinations in which the condensate is removed after each step, simulating continuous slag removal from the MHD system. MHDGAS retains the condensate for each step, simulating flow of condensate (and gas) through the MHD system.

  5. RADIATION SAFETY JUSTIFICATION FOR THE LONG-TERM STORAGE OF GAS CONDENSATE IN THE UNDERGROUND RESERVOURS FORMED BY THE NUCLEAR EXPLOSION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    I. K. Romanovich

    2010-01-01

    Full Text Available The paper presents approaches to the safety justification of the gas condensate and brine long-term storage in the underground reservoirs formed by the nuclear explosion technology. Gas condensate and brine are the intermediate level liquid radioactive waste containing isotopes: 3Н, 137Cs and 90Sr, in traces - 239Pu, 235U, 241Am.Safety of the gas condensate and brine long-term storage in the underground reservoirs is assessed on the base of the multi-barrier principle implementation, used during radioactive waste disposal. It is shown that the gas condensate and brine long-term storage in the sealed underground reservoirs formed by nuclear explosion technologies in salt domes does not lead to the surface radioactive contamination and population exposure.

  6. Bose-Einstein condensation of a charged relativistic ideal gas in a general homogeneous magnetic field

    International Nuclear Information System (INIS)

    Toms, D.J.

    1994-01-01

    It is shown how the effective action formalism and ζ-function regularization can be used to study Bose-Einstein condensation for a relativistic charged scalar field in a general homogeneous magnetic field in a spacetime of arbitrary dimension. In the special case where the magnetic field has only one component, Bose-Einstein condensation occurs at high temperature only for D≥5 where D is the spatial dimension. When Bose-Einstein condensation does occur the ground-state expectation value of the scalar field is not constant and we determine its value. If the magnetic field has p independent nonzero components we show that the condition for Bose-Einstein condensation is D≥3+2p. In particular, Bose-Einstein condensation can never occur if the magnetic field has all of its independent components nonzero. The problem of Bose-Einstein condensation in a cylindrical box in D spatial dimensions with a uniform magnetic field directed along the axis of the cylinder is also discussed

  7. Natural gas hydrates. Experimental techniques and their applications

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Yuguang; Liu, Changling (eds.) [Qingdao Institute of Marine Geology (China). Gas Hydrate Laboratory

    2013-07-01

    Focuses on gas hydrate experiment in laboratory. Intends to provide practical significant parameters for gas hydrate exploration and exploitation in the oceanic and permafrost environments. Consists of different themes that present up-to-date information on hydrate experiments. ''Natural Gas Hydrates: Experimental Techniques and Their Applications'' attempts to broadly integrate the most recent knowledge in the fields of hydrate experimental techniques in the laboratory. The book examines various experimental techniques in order to provide useful parameters for gas hydrate exploration and exploitation. It provides experimental techniques for gas hydrates, including the detection techniques, the thermo-physical properties, permeability and mechanical properties, geochemical abnormalities, stability and dissociation kinetics, exploitation conditions, as well as modern measurement technologies etc.

  8. Natural gas: intersection of men, techniques and markets

    International Nuclear Information System (INIS)

    Laupretre, J.M.; Rasmusen, H.J.

    1996-01-01

    The 113. gas conference has held in Paris between the 10. to 13. September 1996. Its topic was ''the natural gas: intersection of men, techniques and markets''. Jean-Michel Laupretre, chairman of the technical association of the gas industry in France (TAG), in his opening allocution and Hans Rasmusen, chairman of the international Union of gas industry, in his Union message have stressed on the actuality of such a subject. (O.M.)

  9. A thermodynamics model for morphology prediction of aluminum nano crystals fabricated by the inert gas condensation method

    Science.gov (United States)

    Wen, Yu; Xia, Dehong

    2018-03-01

    The purpose of this study is to provide scientific guidance for the morphological control of nanoparticle synthesis using the gas phase method. A universal thermodynamics model is developed to predict the morphology of nanoparticles fabricated using the inert gas condensation method. By using this model, the morphologies of aluminum nanocrystals are predicted under various preparation conditions. There are two types of energy that jointly determine the formation of nanoparticle morphology—Gibbs free energy for nanoparticles and energy variation during the process. The results show that energy variation dominates morphology formation when the cooling rate is less than 2 × 1011 K s-1 in the aluminum nanocrystal production process. At the beginning of the nanoparticle growth, the most stable morphology is predicted to be spherical, but the energetically preferred morphology becomes cubic as the particle grows. The turning point in the particle size at which spherical morphology is no longer the most stable morphology is exhibited as a function of pressure in a condensation chamber for different cooling rates. In this paper, we focus on the need for morphology prediction based on preparation conditions. It is concluded that nanoparticles with various morphologies could be obtained by adjusting the cooling rate and pressure in the condensation chamber.

  10. Novel gas-based detection techniques

    International Nuclear Information System (INIS)

    Graaf, Harry van der

    2009-01-01

    This year we celebrate the 100th birthday of gaseous detectors: Hans Geiger operated the first gas-filled counter in Manchester in 1908. The thin wires, essential for obtaining gas amplification, have been replaced by Micro Pattern Gas Detectors (MPGDs): Micromegas (1995) and GEM (1996). In the GridPix detector, each of the grid holes of a MPGD is equipped with its own electronic readout channel in the form of an active pixel in suitable pixel CMOS chips. By means of MEMS technology, the grid has been integrated with the chip, forming a monolithic readout device for gas volumes. By applying a protection layer made of hydrogenated amorphous silicon, the chips can be made spark proof. New protection layers have been made of silicon nitride. The use of gas as detection material for trackers is compared to Si, and the issue of chamber aging is addressed. New developments are set out: the development of Micro Channel Plates, integrated on pixel chips, the development of electron emission foil, and the realization of TimePix-2: a general-purpose pixel chip with time and amplitude measurement, per pixel, of charge signals.

  11. Water-saturated systems of the largest gas and gas-condensate deposits of the USSR. Vodonapornye sistemy krupneishikh gazovykh i gazokondensatnykh mestorozhdenii sssr

    Energy Technology Data Exchange (ETDEWEB)

    Kortsenshtein, V.N.

    1977-01-01

    A description is given of water-pressure systems in a number of the largest gas and gas-condensate fields of the Soviet Union, whose industrial reserves exceed 500 billion cubic meters. These include fields located in the concluding stage of development with sharply reduced recovery (Shebelinsk), fields that have just begun to operate and are characterized by increasing production (Vuktyl, Medved, Orenburg, Shatlyk, Urengoisk), and fields that are not yet developed (Yamburg and Zapolyar). Problems in the theory and practice of studying water-pressure systems of the largest gas and gas-condensate fields are analyzed primarily in connection with conditions required for their rational development which would provide for a maximum extraction of hydrocarbons from the interior. Importance is also given to the hydrogeological aspects of the formation of large hydrocarbon deposits and their distribution in the earth's crust. The most reliable factual materials on hydrogeology are utilized. The book is designed for personnel in the gas and oil industries, hydrogeologists, and scientists interested in problems of the formation, survey, and development of the largest hydrocarbon deposits. 92 references, 65 figures, 71 tables.

  12. Water recovery and air humidification by condensing the moisture in the outlet gas of a proton exchange membrane fuel cell stack

    International Nuclear Information System (INIS)

    Wan, Z.M.; Wan, J.H.; Liu, J.; Tu, Z.K.; Pan, M.; Liu, Z.C.; Liu, W.

    2012-01-01

    Humidification is one of the most important factors for the operation of proton exchange membrane fuel cell (PEMFC). To maintain the membrane at hydrated state, plenty of water is needed for the state-of-the-art of PEMFC technology, especially in large power applications or long time operation. A condenser is introduced to separate liquid water from the air outlet for air self-sufficient in water of the stack in this study. The condensed temperature at the outlet of the condenser and water recovered amount for air self-sufficient in water are investigated theoretically and experimentally. It is shown that the condensed temperature for air self-sufficient in water is irrelevant with the working current of the stack. When the condenser outlet temperature was above the theoretical line, recovery water was not sufficient for the air humidification. On the contrary, it is sufficient while the temperature was below the theoretical line. It is also shown that when the moisture is sufficiently cooled, large amount water can be separated from the outlet gas, and it increased almost linearly with the time. With the introduction of the condenser, the recovered amount of water can easily satisfy the air self-sufficient in water by condensing the outlet gas to a proper temperature. - Highlights: ► We introduce a condenser to separate liquid water from the air outlet in the stack. ► The mechanism of air self-sufficient in water by condensing gas is presented. ► The condensed temperature and water recovered amount are investigated. ► An experiment is present to validate simplicity and feasibility of the criterion. ► The criterion for air humidification is used for choosing the condenser.

  13. A new technique for pumping hydrogen gas

    Science.gov (United States)

    Friedman, I.; Hardcastle, K.

    1970-01-01

    A system for pumping hydrogen gas without isotopic fractionation has been developed. The pump contains uranium metal, which when heated to about 80??C reacts with hydrogen to form UH3. The UH3 is heated to above 500??C to decompose the hydride and regenerate the hydrogen. ?? 1970.

  14. Laboratory Scoping Tests Of Decontamination Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, William R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-01-21

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task seeks to examine the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also

  15. Disrupting the balance of natural fluid systems during the working of gas condensate deposits. Narushenie ravnovesiya prirodnykh flyuidal'nykh sistem pri razrabotke gazovykh i gazokondensatnykh mestorozhdenii

    Energy Technology Data Exchange (ETDEWEB)

    Kortsenshtein, V.N.

    1980-01-01

    Natural processes that occur in the ground as a result of almost complete or partial depletion of large gas and gas-condensate deposits are analyzed. Problems concerned with the disruption of the fluid systems equilibrium are examined as represented by interstitial water and industrial gaseous and gas-condensate accumulations. Observations over a period of 20-25 years were made of the depleted deposits of North-Stavropol', Gazlin, and Shebel, whose initial hydrogeological background that serves as the basis of the reference system, has been studied in detail. Information is also presented on recently exploited water-vapor systems, such as the large Vuktyl', Orenburg, Medvezh', and Shatlyk deposits. The book is intended for a broad spectrum of geologists, hydrogeologists, and engineers interested in geology and the working of gas and gas condensate deposits. 36 references, 27 figures, 35 tables.

  16. Determination of the vertical distribution and areal of the composition in volatile oil and/or gas condensate reservoirs

    International Nuclear Information System (INIS)

    Santos Santos, Nicolas; Ortiz Cancino, Olga Patricia; Barrios Ortiz, Wilson

    2005-01-01

    The compositional variation in vertical and areal direction due to gravitational and thermal effects plays an important role in the determination of the original reserves in-situ and in the selection of the operation scheme for volatile oil and/or gas condensate reservoirs. In this work we presented the mathematical formulation of the thermodynamic behavior experienced by compositional fluids, such as volatile oil and/or gas condensate, under the influence of the mentioned effects (gravitational and thermal), which was implemented in a software tool, this tool determine the compositional variation in vertical direction and, in addition, it allows to know the saturation pressure variation in the hydrocarbon column and the location of the gas-oil contact. With the obtained results, product of the use of this tool, was developed a methodology to obtain one first approach of the compositional variation in areal direction to obtain compositional spatial distribution (iso composition maps) in the reservoir, for components like the methane, which experiences the greater variations. These iso composition maps allow to determine the location of the hydrocarbon deposits, in such a way that the production strategies can be selected and be applied to maximize the recovery, such as in fill wells, perforation of new zones, EOR processes, etc

  17. Gas transport and separation with ceramic membranes. Part I: Multilayer diffusion and capillary condensation

    NARCIS (Netherlands)

    Uhlhorn, R.J.R.; Uhlhorn, R.J.R.; Keizer, Klaas; Burggraaf, Anthonie; Burggraaf, A.J.

    1992-01-01

    Multilayer diffusion and capillary condensation of propylene on supported γ-alumina films greatly improved the permeability and selectivity. Multilayer diffusion, occurring at relative pressures of 0.4 to 0.8 strongly increased the permeability of 6 times the Knudsen permeability, yielding

  18. Conversion of straight-run gas-condensate benzenes into high- octane gasolines based on modified ZSM-5 zeolites

    International Nuclear Information System (INIS)

    Erofeev, V; Reschetilowski, V; Khomajakov, I; Egorova, L; Volgina, T; Tatarkina, A

    2014-01-01

    This paper describes the conversion of straight-run benzene of gas condensate into high-octane gasoline based on zeolite catalyst ZSM-5, modified in binary system oxide- based Sn (III) and Bi (III). It was defined that the introduction of the binary system oxide-based Sn(III) and Bi (III) into the basic zeolite results in the 2-fold increase of its catalytic activity.High-octane gasoline converted from straight-run benzene is characterized by a low benzol content in comparison to the high-octane benzenes produced during the catalytic reforming

  19. On the adequacy of wall functions to predict condensation rates from steam-noncondensable gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Dehbi, A., E-mail: abdel.dehbi@psi.ch

    2013-12-15

    Highlights: • Work investigates the effect of near-wall mesh resolution on CFD predictions. • Case study: turbulent condensation in the presence of noncondensable gases. • Wall functions largely underpredict condensation rates at boundary layer onset. • When boundary layer is developed, wall functions predictions are reasonable. • Prescribed wall functions must be compatible with prevailing flow regime. - Abstract: As one looks forward to applying CFD based methods to simulate turbulent flows in larger volumes up to containment scales, the mesh resolution, especially near the walls, becomes one of the main issues dictating the feasibility of the simulation. The wall-function approach is a natural choice to minimize the computational size of the problem and make it tractable. In the current investigation, we compare the wall-function to the fully resolved boundary layer approaches for the prediction of vapor condensation rates on cold walls in the presence of noncondensable gases. We simulate three sets of geometric configurations. The first two sets relate to domains which are small (height of 2 m) and medium (height 4.8 m), and for which experimental heat transfer data are available. In the third set, we look at a hypothetical large 2D rectangular domain in which the condenser height is comparable to that of typical NPP containments (20 m). In the developing region of the boundary layer, it is found that the wall function treatment leads to substantial deviations from the wall resolved approach and available experimental data. Further downstream, however, when the boundary layer is fully developed, the discrepancy is greatly reduced. It is therefore concluded that the wall-function formulation is able to provide predictions of condensation rates that are similar to wall-resolved treatments in simple forced flows for which fully developed boundary layers can be assumed over most of the domain. Care must however be exercised to ensure the chosen wall

  20. Study of the Condensed Matter Dynamics by the Deep Inelastic Neutron Technique

    International Nuclear Information System (INIS)

    Blostein, Juan Jeronimo

    2004-01-01

    physical phenomena.For the special case of light water/ heavy water mixtures we present calculations that reproduce the behavior of the reported anomalies on the hydrogen-deuterium neutron cross section rate.We present total cross section measurements of such liquid mixtures, in total agreement with the expected values, whereby we conclude that the purported anomalous cross sections (reported after employing the convolution approximation in the eVS data treatment) do not exist.The absence of anomalies in the total cross sections of those liquid mixtures provides a clear evidence of the invalidity of the convolution formalism usually employed in the eVS data treatment. In view of the main motivation that originated the eVS technique, and the clear invalidity of the convolution formalism, we present for the first time the exact formalism to obtain the nuclear impulse distributions in condensed matter systems, starting form the experimentally observed intensity profiles.Such formalism, valid for an arbitrary impulse distribution, does not require the harmonic potential hypothesis, and involves an integration kernel that depends analytically only on the instrumental characteristics, and is independent of the sample characteristics. Our work, besides assessing the magnitude of the inaccuracy of the convolution formalism, establishes the basis for a correct treatment of the experimental data obtained with this technique.On the experimental side, we implemented successfully the eVS technique in the linear accelerator pulsed neutron facility at the Bariloche Atomic Center, thus being the second laboratory in the world to employ it regularly.Monte Carlo simulation presented in this thesis, show the importance to adequately select the sample thickness, and to correct by multiple scattering, attenuation and detector efficiency effects, and also to employ the exact formalism.To this end it is necessary to characterize in detail the different elements that compose the experimental

  1. 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 %.

  2. Time reversal technique for gas leakage detection.

    Science.gov (United States)

    Maksimov, A O; Polovinka, Yu A

    2015-04-01

    The acoustic remote sensing of subsea gas leakage traditionally uses sonars as active acoustic sensors and hydrophones picking up the sound generated by a leak as passive sensors. When gas leaks occur underwater, bubbles are produced and emit sound at frequencies intimately related to their sizes. The experimental implementation of an acoustic time-reversal mirror (TRM) is now well established in underwater acoustics. In the basic TRM experiment, a probe source emits a pulse that is received on an array of sensors, time reversed, and re-emitted. After time reversal, the resulting field focuses back at the probe position. In this study, a method for enhancing operation of the passive receiving system has been proposed by using it in the regime of TRM. Two factors, the local character of the acoustic emission signal caused by the leakage and a resonant nature of the bubble radiation at their birth, make particularly effective scattering with the conjugate wave (CW). Analytical calculations are performed for the scattering of CW wave on a single bubble when CW is formed by bubble birthing wail received on an array, time reversed, and re-emitted. The quality of leakage detection depends on the spatio-temporal distribution of ambient noise.

  3. Inert-Gas Condensed Co-W Nanoclusters: Formation, Structure and Magnetic Properties

    Science.gov (United States)

    Golkar-Fard, Farhad Reza

    Rare-earth permanent magnets are used extensively in numerous technical applications, e.g. wind turbines, audio speakers, and hybrid/electric vehicles. The demand and production of rare-earth permanent magnets in the world has in the past decades increased significantly. However, the decrease in export of rare-earth elements from China in recent time has led to a renewed interest in developing rare-earth free permanent magnets. Elements such as Fe and Co have potential, due to their high magnetization, to be used as hosts in rare-earth free permanent magnets but a major challenge is to increase their magnetocrystalline anisotropy constant, K1, which largely drives the coercivity. Theoretical calculations indicate that dissolving the 5d transition metal W in Fe or Co increases the magnetocrystalline anisotropy. The challenge, though, is in creating a solid solution in hcp Co or bcc Fe, which under equilibrium conditions have negligible solubility. In this dissertation, the formation, structure, and magnetic properties of sub-10 nm Co-W clusters with W content ranging from 4 to 24 atomic percent were studied. Co-W alloy clusters with extended solubility of W in hcp Co were produced by inert gas condensation. The different processing conditions such as the cooling scheme and sputtering power were found to control the structural state of the as-deposited Co-W clusters. For clusters formed in the water-cooled formation chamber, the mean size and the fraction crystalline clusters increased with increasing power, while the fraction of crystalline clusters formed in the liquid nitrogen-cooled formation chamber was not as affected by the sputtering power. For the low W content clusters, the structural characterization revealed clusters predominantly single crystalline hcp Co(W) structure, a significant extension of W solubility when compared to the equilibrium solubility, but fcc Co(W) and Co3W structures were observed in very small and large clusters, respectively. At high

  4. Basic design of the test facility for the two-phase critical flow with non-condensable gas

    International Nuclear Information System (INIS)

    Chang, Seok Kyu; Kim, Chang Hwe; Chung, Chang Hwan

    2000-12-01

    The two-phase critical flow test with non-condensible gas is for the simulation of the critical flow phenomena which can be occurred during SB-LOCA on SMART reactor. The basic design of the test facility for the actual installation is performed from the basis of the previous conceptual design according to the test requirements. The 1.3m 3 pressure vessel has the circulation pipeline which contains pump(5m 3 /hr), main heater(150KW) and cooler for heating the working fluid to the test temperature within 6 hours. The N2 gas, water supply line are attached to the upper part and test section, flowmeter and various sensors are installed at the lower part of the pressure vessel. The suppression tank is for the storage and cooling of the discharged water. The N2 gas storage tank provides the system pressure to the pressure vessel during the test. The 0.7m 3 N2 gas injection tank supplies the required N2 gas to the entrance of the test section. Since these N2 supply systems require much amount of gas during short period, multistage valve systems and optimal control logics are needed and applied. For the filling of the N2 gas to the N2 storage tank, 5m 3 LN2 tank and related gas converting system were designed. The operating mode of the test facility can be classified to the starting, steady, main test and cooling modes and the proper monitoring and control logics are developed for each operating mode. The operation of the test facility is performed through the PLC and the acquisition of the test data is done with DAS

  5. Theory of a condensed charged-Bose, charged Fermi gas and Ginzburg--Landau studies of superfluid 3He

    International Nuclear Information System (INIS)

    Dahl, D.A.

    1976-01-01

    Two independent topics in the field of condensed matter physics are examined: the condensed charged-Bose, charged Fermi gas and superfluid 3 He. Green's function (field theoretic) methods are used to derive the low-temperature properties of a dense, neutral gas of condensed charged bosons and degenerate charged fermions. Restriction is made to the case where the fermion mass is much lighter than the boson mass. Linear response and the density-density correlation function are examined and shown to exhibit two collective modes: a plasmon branch and a phonon branch with speed equal to that of ionic sound in solids. Comparison with a possible astrophysical application (white dwarf stars) is made. The behavior near the superfluid transition temperature (Ginzburg--Landau regime) of 3 He is then studied. Gorkov equations are derived and studied in the weak-coupling limit. In this way the form and order of magnitude estimates of coefficients appearing in the Ginzburg--Landau theory are obtained. Weak-coupling particle and spin currents are derived. Various perturbations break the large degeneracy of the states and have experimental implications. The electric contribution to the Ginzburg--Landau free energy is studied for the proposed A and B phases. Imposition of an electric field orients the axial state, but does not give rise to shifts in the NMR resonances. Shifts and discontinuous jumps in the longitudinal and transverse signals are predicted for the Balian--Werthamer state, the details depending on the relative strengths of the fields, as well as the angle between them

  6. Diagnostics of gas behind shock waves by refractive optical techniques

    International Nuclear Information System (INIS)

    Blaha, J.

    In a brief outline of optical methods for measuring neutral gas and plasma parameters, techniques are specifically dealt with based on the interferometric measurement of the refractive index. The investigation is shown of gas density changes in a shock tube using the optical Mach-Zehnder interferometer. While in a neutral gas the refractive index is determined by gas density, in a plasma the effects of all components, ie., electrons, ions and atoms are additive. The contributions to refraction from the various components may, in view of the different character and frequencies of the components, be resolved by measurement on more than one wavelength. (J.U.)

  7. Acute ecotoxicology of natural oil and gas condensate to coral reef larvae.

    Science.gov (United States)

    Negri, Andrew P; Brinkman, Diane L; Flores, Florita; Botté, Emmanuelle S; Jones, Ross J; Webster, Nicole S

    2016-02-19

    Risks posed by oil spills to coral reefs are difficult to evaluate, partially due to the absence of studies that adequately assess toxicity to relevant coral reef species. Here we experimentally tested the acute toxicity of condensate, representing a fraction of light crude oil, to coral (Acropora tenuis) and sponge (Rhopaloeides odorabile) larvae. The metamorphosis of coral larvae was inhibited at total petroleum aromatic hydrocarbon (TPAH) concentrations of water accommodated fractions (WAF) as low as 103 μg l(-1), similar to concentrations detected in seawater following large spills. The sensitivity of coral larvae increased by 40% when co-exposed to UV light that they might encounter in shallow reefal systems. Condensate WAF was more toxic to coral larvae than predicted by summing the toxicity of its main components (benzene, toluene, p-xylene and napthalene). In contrast, the sensitivity of sponge larvae to condensate WAF (>10,000 μg l(-1) TPAH) was far less than coral in the presence and absence of UV, but similar to that of other marine invertebrates. While these results highlight the relative sensitivity of coral larvae to oil, further research is needed to better understand and predict the impacts and risks posed by hydrocarbons to tropical reef systems.

  8. Application of fluorinated nanofluid for production enhancement of a carbonate gas-condensate reservoir through wettability alteration

    Science.gov (United States)

    Sakhaei, Zahra; Azin, Reza; Naghizadeh, Arefeh; Osfouri, Shahriar; Saboori, Rahmatollah; Vahdani, Hosein

    2018-03-01

    Condensate blockage phenomenon in near-wellbore region decreases gas production rate remarkably. Wettability alteration using fluorinated chemicals is an efficacious way to vanquish this problem. In this study, new synthesized fluorinated silica nanoparticles with an optimized condition and mean diameter of 50 nm is employed to modify carbonate rock surface wettability. Rock characterization tests consisting Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive x-ray Spectroscopy (EDX) were utilized to assess the nanofluid adsorption on rock surface after treatment. Contact angle, spontaneous imbibition and core flooding experiments were performed to investigate the effect of synthesized nanofluid adsorption on wettability of rock surface and liquid mobility. Results of contact angle experiments revealed that wettability of rock could alter from strongly oil-wetting to the intermediate gas-wetting even at elevated temperature. Imbibition rates of oil and brine were diminished noticeably after treatment. 60% and 30% enhancement in pressure drop of condensate and brine floods after wettability alteration with modified nanofluid were observed which confirm successful field applicability of this chemical.

  9. Off-diagonal long-range order, cycle probabilities, and condensate fraction in the ideal Bose gas.

    Science.gov (United States)

    Chevallier, Maguelonne; Krauth, Werner

    2007-11-01

    We discuss the relationship between the cycle probabilities in the path-integral representation of the ideal Bose gas, off-diagonal long-range order, and Bose-Einstein condensation. Starting from the Landsberg recursion relation for the canonic partition function, we use elementary considerations to show that in a box of size L3 the sum of the cycle probabilities of length k>L2 equals the off-diagonal long-range order parameter in the thermodynamic limit. For arbitrary systems of ideal bosons, the integer derivative of the cycle probabilities is related to the probability of condensing k bosons. We use this relation to derive the precise form of the pik in the thermodynamic limit. We also determine the function pik for arbitrary systems. Furthermore, we use the cycle probabilities to compute the probability distribution of the maximum-length cycles both at T=0, where the ideal Bose gas reduces to the study of random permutations, and at finite temperature. We close with comments on the cycle probabilities in interacting Bose gases.

  10. ν-Dimensional ideal quantum q-gas: Bose-Einstein condensation and λ-point transition

    International Nuclear Information System (INIS)

    R-Monteiro, M.; Roditi, I.; Rodrigues, L.M.C.S.

    1994-01-01

    The authors consider an ideal quantum q-gas in ν spatial dimensions and energy spectrum ω i αp α . Departing from the Hamiltonian H = ω[N], the authors study the effect of the deformation on thermodynamic functions and equation of state of that system. The virial expansion is obtained for the high temperature (or low density) regime. The critical temperature is higher than in non-deformed ideal gases. They show that Bose-Einstein condensation always exists (unless when ν/α = 1) for finite q but not for q = ∞. Employing numerical calculations and selecting for ν/α the values 3/2, 2 and 3, the authors show the critical temperature as a function of q, the specific heat C V and the chemical potential μ as functions of T/T c q for q = 1.05 and q= 4.5. C V exhibits a λ-point discontinuity in all cases, instead of the cusp singularity found in the usual ideal gas. The results indicate that physical systems which have quantum symmetries can exhibit Bose-Einstein condensation phenomenon, the critical temperature being favored by the deformation parameter

  11. Bench scale experiments for the remediation of Hanford Waste Treatment Plant low activity waste melter off-gas condensate

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M.L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Poirier, Michael [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-08-11

    The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter, so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.

  12. LABORATORY OPTIMIZATION TESTS OF TECHNETIUM DECONTAMINATION OF HANFORD WASTE TREATMENT PLANT LOW ACTIVITY WASTE OFF-GAS CONDENSATE SIMULANT

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, K.; Nash, C.; McCabe, D.

    2014-09-29

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also

  13. Visualization of gas dissolution following upward gas migration in porous media: Technique and implications for stray gas

    Science.gov (United States)

    Van De Ven, C. J. C.; Mumford, Kevin G.

    2018-05-01

    The study of gas-water mass transfer in porous media is important in many applications, including unconventional resource extraction, carbon storage, deep geological waste storage, and remediation of contaminated groundwater, all of which rely on an understanding of the fate and transport of free and dissolved gas. The novel visual technique developed in this study provided both quantitative and qualitative observations of gas-water mass transfer. Findings included interaction between free gas architecture and dissolved plume migration, plume geometry and longevity. The technique was applied to the injection of CO2 in source patterns expected for stray gas originating from oil and gas operations to measure dissolved phase concentrations of CO2 at high spatial and temporal resolutions. The data set is the first of its kind to provide high resolution quantification of gas-water dissolution, and will facilitate an improved understanding of the fundamental processes of gas movement and fate in these complex systems.

  14. The specifics of operating minor deposits (as given by the examples of gas condensate deposits of the Northern Caucasus

    Directory of Open Access Journals (Sweden)

    Р. А. Гасумов

    2016-08-01

    Full Text Available One of the most important directions in upgrading well productivity in the process of mining hydrocarbons consists in fighting with salt formation and salt deposition. Solving that problem becomes especially actual when operating deposits that are in their final stage of exploitation in complex mining and geological conditions accompanied by deposition of salts in the well foot area of oil bed and their sedimentation on the sub-surface and surface equipment. It provokes a drop in well productivity and results in off-schedule repair works. Specifics are considered of exploiting minor gas condensate deposits of the Northern Caucasus that are operated under complicated mining and geological conditions of anomalously high bed pressures, high temperatures, strong depressions on the beds and inflow of mineralized water from water saturated seams.Processes are studied of salt deposition from heavy hydrocarbons in the well foot and the bed area surrounding it. Water sample analyses data from different wells have demonstrated that the main salts carrier is the associated water, and the principal sedimenting agents are corrosion products, as confirmed by the results of microscopic studies. The dynamics is presented of salt deposition in the “well foot – wellhead – separator” system retrieved from the results of studies of reaction products in the well foot zone of oil bed.It is demonstrated that the efficiency of struggling with salt deposition in the course of mining hydrocarbons depends on comprehensive approach to the problem, the principal thrust lying with prevention of such deposition.Possible ways are considered to prevent precipitation of ferric compounds in the course of operating gas condensate wells, a way is suggested to intensify gas inflow.

  15. Numerical simulation of gas-liquid two-phase flow behavior with condensation heat transfer

    International Nuclear Information System (INIS)

    Takamori, Kazuhide; Murase, Michio; Baba, Yoshikazu; Aihara, Tsuyoshi.

    1995-01-01

    In this study, condensation heat transfer experiments were performed in order to verify a condensation heat transfer model coupled with a three-dimensional two-phase flow analysis. In the heat transfer model, the liquid film flow rate on the heat transfer tubes was calculated by a mass balance equation and the liquid film thickness was calculated from the liquid film flow rate using Nusselt's laminar flow model and Fujii's equation for steam velocity effect. In the experiments, 112 horizontal staggered tubes with an outer diameter of 16 mm and length of 0.55 m were used. Steam and spray water were supplied to the test section, and inlet quality was controlled by the spray water flow rate. The temperature was 100degC and the pressure was 0.1 MPa. The overall heat transfer coefficients were measured for inlet quality of 13-100%. From parameter calculations for the falling liquid film ratio from the upper tubes to the lower tubes, the calculated overall heat transfer coefficients agreed with the data to within ±5% at the falling liquid film ratio of 0.7. (author)

  16. Conceptual design of the test facility for the two-phase critical flow with non-condensable gas

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Seok Kyu; Chung, Chang Hwan

    2000-12-01

    The two-phase critical flow test with non-condensible gas is for the simulation of the critical flow phenomena which can be occurred during SB-LOCA on SMART reactor. The requirements of the critical flow test are 7{approx}20mm pipe break dia., 7{approx}12MPa stagnation pressure, 0{approx}60 deg C subcooling degree and 0{approx}0.5kg/s N2 gas flow rate. For the satisfaction of these requirements on the test facility, critical flow rates were calculated with various models. With the selected reference pressure vessel(1.3m{sup 3}), the conceptual design of the test facility was performed. The important components of the test facility are the pressure vessel which has main circulation line, the test section attached to the bottom of the pressure vessel, suppression tank, the N2 gas supply tanks for maintaining the system pressure and N2 gas flow rate at test section and the auxiliary N2 gas converting system. For the measurements of the critical flow rate, flowmeter and level gauge is installed at the upstream of the test section and the pressure vessel, respectively. The realtime pressure control system is installed at the entrance of the pressure vessel for maintaining the system pressure and the N2 gas flow regulating system is also installed at the upstream of the test section. The design of the control and monitoring system for the operation of the test facility and the DAS for acquiring the test data were also performed. The conceptual operating process of the test facility was determined.

  17. Conceptual design of the test facility for the two-phase critical flow with non-condensable gas

    International Nuclear Information System (INIS)

    Chang, Seok Kyu; Chung, Chang Hwan

    2000-12-01

    The two-phase critical flow test with non-condensible gas is for the simulation of the critical flow phenomena which can be occurred during SB-LOCA on SMART reactor. The requirements of the critical flow test are 7∼20mm pipe break dia., 7∼12MPa stagnation pressure, 0∼60 deg C subcooling degree and 0∼0.5kg/s N2 gas flow rate. For the satisfaction of these requirements on the test facility, critical flow rates were calculated with various models. With the selected reference pressure vessel(1.3m 3 ), the conceptual design of the test facility was performed. The important components of the test facility are the pressure vessel which has main circulation line, the test section attached to the bottom of the pressure vessel, suppression tank, the N2 gas supply tanks for maintaining the system pressure and N2 gas flow rate at test section and the auxiliary N2 gas converting system. For the measurements of the critical flow rate, flowmeter and level gauge is installed at the upstream of the test section and the pressure vessel, respectively. The realtime pressure control system is installed at the entrance of the pressure vessel for maintaining the system pressure and the N2 gas flow regulating system is also installed at the upstream of the test section. The design of the control and monitoring system for the operation of the test facility and the DAS for acquiring the test data were also performed. The conceptual operating process of the test facility was determined

  18. Problems of the protection of bioresources development ofthe Bovanenkovo gas condensate field

    Directory of Open Access Journals (Sweden)

    Vladimir Dmitrievich Bogdanov

    2012-12-01

    Full Text Available The data on the fish fauna and fish food resources in the Bovanenkovo gas field are presented. The estimation of fishery and fishery potential of water bodies, hydrobiological characteristics of water bodies in the studied area are given. It is shown that the arrangement of the gas field leads to overfishing BGKM fish and change the state of aquatic ecosystems associated with the violation of runoff, backfilling flood waters, crossing streams communications, water diversion, pollution, sand mining. Thehydrobionts reaction to anthropogenic influence in the area of the gas field developmentis identified and recommendations to reduce the impact on aquatic ecosystems in the period of construction are given

  19. Experimental study of air-cooled water condensation in slightly inclined circular tube using infrared temperature measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyungdae [Nuclear Engineering Department, Kyung Hee University, Yongin (Korea, Republic of); Kwon, Tae-Soon [Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Dong Eok, E-mail: dekim@knu.ac.kr [Department of Precision Mechanical Engineering, Kyungpook National University, Sangju (Korea, Republic of)

    2016-11-15

    Highlights: • Air-cooled condensation experiments in an inclined Pyrex glass tube were performed. • High-resolution wall temperature data and flow regime formations could be obtained. • The local heat flux was strongly dependent on the air-side heat transfer. • A CFD analysis was conducted for calculating the local heat flux distribution. - Abstract: This study presents the results of an investigation of the air-cooled water condensation heat transfer characteristics inside a slightly inclined circular tube made of transparent Pyrex glass. The high-resolution wall temperature data and stratified film formations could be obtained with the assistance of an infrared (IR) thermometry technique and side-view visualization using a CCD camera. In all experimental cases, the condensation flow patterns were in the fully-stratified flow region. In addition, the experimentally measured void fraction corresponded well with the logarithmic mean void fraction model. The local temperature differences in the cooling air flow across the condenser tube and high-resolution temperature profiles on the tube’s outer wall were obtained in the experimental measurements. Under the experimental conditions of this study, the local heat flux distributions in the longitudinal direction of the test tube were strongly dependent on the cooling air velocity. And, with the help of IR thermometry, the tube outer wall temperature data at 45 local points could be measured. From the data, the asymmetry distribution of the local wall temperatures and the accurate location of the transition from two-phase mixture to single phase liquid inside the tube could be obtained. Also, the analysis of the thermal resistances by condensation, wall conduction and air convection showed that the air convective heat transfer behavior can play a dominant role to the local heat transfer characteristics. Finally, in order to obtain the local heat flux distribution along the tube’s outer wall, a two

  20. Laboratory Optimization Tests of Technetium Decontamination of Hanford Waste Treatment Plant Direct Feed Low Activity Waste Melter Off-Gas Condensate Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-12-23

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste.

  1. Laboratory Optimization Tests of Decontamination of Cs, Sr, and Actinides from Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-01-06

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also substantially decrease the LAW vitrification mission duration and quantity of glass waste.

  2. Defect formation in fluoropolymer films at their condensation from a gas phase

    Science.gov (United States)

    Luchnikov, P. A.

    2018-01-01

    The questions of radiation defects, factors of influence of electronic high-frequency discharge plasma components on the molecular structure and properties of the fluoropolymer vacuum films synthesized on a substrate from a gas phase are considered. It is established that at sedimentation of fluoropolymer coverings from a gas phase in high-frequency discharge plasma in films there are radiation defects in molecular and supramolecular structure because of the influence of active plasma components which significantly influence their main properties.

  3. Experience in oil field processing of gas and condensate at the Shatlyk deposits

    Energy Technology Data Exchange (ETDEWEB)

    Dalmatov, V.V.; Chernikov, Ye.I.; Govorun, V.P.; Turevskiy, Ye.N.

    1983-01-01

    The operation of installations for preparing gas are analyzed, along with the operation of individual technological devices at the Shatlyk deposit, the basic things which hinder the support of the designed low temperature conditions are shown and recommendations for standardizing the operation of the technological installations are given. Experience in the operation of the gas preparation installations at the Shatlyk deposit is recommended for use in deposits being introduced into development.

  4. Pyrolysis of low-boiling gas condensate of the Shatlyk field

    Energy Technology Data Exchange (ETDEWEB)

    Khankuliyev, K.; Kul' dzhayev, B.A.; Magaril, R.Z.; Sergiyenko, S.R.

    1984-01-01

    A study was made of pyrolysis of the 60-180/sup 0/C fraction of condensate from the Shatlyk field at temperature 800-850/sup 0/ and contact time of 0.3-1.5 sec. An optimal pyrolysis mode was selected (825/sup 0/C, contact time 0.5-0.7 sec) at which there is simultaenously high yield of ethylene (36-40%) and olefins C/sub 2/-C/sub 4/ (60-61%). It is shown that the total yield of olefins and ethylene, as well as the correlation in them of ethylene/propylene, can be regulated by changing the temperature and contact time in the process. The maximum ethylene yields with the highest selectivity indicators for ethylene are observed under the following conditions: temperature 825/sup 0/C and contact time 0.9 sec; 850/sup 0/C and 0.7 sec.

  5. Analysis of the test results for the two-phase critical flow with non-condensible gas

    International Nuclear Information System (INIS)

    Chang, S. K.; Chung, C. H.; Park, H. S.; Min, K. H.; Choi, N. H.; Kim, C. H.; Lee, S. H.; Kim, H. C.; Chang, M. H.

    2002-07-01

    The two-phase critical flow test was performed for simulating the pipe break accident of SMART reactor. The requirements of the critical flow test are 7∼20mm pipe break dia., 7∼12MPa stagnation pressure, 0∼60 .deg. C subcooling degree and 0∼0.5kg/s N 2 gas flow rate. The test section is sharp edged pipe type which has the dimension of I.D.=20, L=300mm and I.D.=10.9, L=1000mm. The test conditions are 4, 7, 10 MPa at stagnation pressure, 0, 20, 50 .deg. C of subcooling degree and 0.028∼0.39 kg/s of N 2 injection gas flowrate. The measured data at test section and other components in terms of pressure, temperature and flowrate were collected in DAS computer with maintaining the steady state conditions at least 60 seconds. From the test results, the critical characteristics of the break pipe were analysed and verified the capacity of the test facility. For the verification of the Modified Henry-Fauske model which can predict the two-phase critical flow with non-condensible gas, the code simulation using MARS which contains the option of the Modified Henry -Fauske model was performed. The simulation results of steady-state two-phase critical flow experiments show that they agree with the measured critical flow rates within 6% root-mean-square error

  6. The use of contained nuclear explosions to create underground reservoirs, and experience of operating these for gas condensate storage

    International Nuclear Information System (INIS)

    Kedrovskij, O.L.; Myasnikov, K.V.; Leonov, E.A.; Romadin, N.M.; Dorodnov, V.F.; Nikiforov, G.A.

    1975-01-01

    Investigations on the creation of underground reservoirs by means of nuclear explosions have been going on in the Soviet Union for many years. In this paper the authors consider three main kinds of sites or formations that can be used for constructing reservoirs by this method, namely, low-permeable rocks, worked-out mines and rock salt formations. Formulae are given for predicting the mechanical effect of an explosion in rocks, taking their strength characteristics into account. Engineering procedures are described for sealing and restoring the emplacement holes, so that they can be used for operating the underground reservoir. Experience with the contruction and operation of a 50 000 m 3 gas-condensate reservoir in a rock salt formation is described. In the appendix to the paper a method is presented for calculating the stability of spherical cavities created by nuclear explosions in rock salt, allowing for the development of elasto-plastic deformations and creep

  7. Effect of scenedesmus acuminatus green algae extracts on the development of Candida lipolytic yeast in gas condensate-containing media

    Science.gov (United States)

    Bilmes, B. I.; Kasymova, G. A.; Runov, V. I.; Karavayeva, N. N.

    1980-01-01

    Data are given of a comparative study of the growth and development as well as the characteristics of the biomass of the C. Lipolytica yeast according to the content of raw protein, protein, lipids, vitamins in the B group, and residual hydrocarbons during growth in media with de-aromatized gas-condensate FNZ as the carbon source with aqueous and alcohol extracts of S. acuminatus as the biostimulants. It is shown that the decoction and aqueous extract of green algae has the most intensive stimulating effect on the yeast growth. When a decoction of algae is added to the medium, the content of residual hydrocarbons in the biomass of C. lipolytica yeast is reduced by 4%; the quantity of protein, lipids, thamine and inositol with replacement of the yeast autolysate by the decoction of algae is altered little.

  8. Repeatability and reproducibility of an automated gas production technique

    NARCIS (Netherlands)

    Laar, van H.; Straalen, van W.M.; Gelder, van A.H.; Boever, de J.L.; heer, D' B.; Vedder, H.; Kroes, R.; Bot, de P.; Hees, van J.; Cone, J.W.

    2006-01-01

    Two ring tests with five and three laboratories, respectively, were conducted to quantify variation within and among laboratories in an automated gas production technique. Single batches of the feeds soya bean meal (SBM), wheat grain (WG), grass silage (GS) and maize gluten meal (MG) were divided

  9. Bose condensation in an attractive fermion gas: From weak to strong coupling superconductivity

    International Nuclear Information System (INIS)

    Nozieres, P.; Schmitt-Rink, S.

    1985-01-01

    We consider a gas of fermions interacting via an attractive potential. We study the ground state of that system and calculate the critical temperature for the onset of superconductivity as a function of the coupling strength. We compare the behavior of continuum and lattice models and show that the evolution from weak to strong coupling superconductivity is smooth

  10. Nonlinear waves in Bose–Einstein condensates: physical relevance and mathematical techniques

    International Nuclear Information System (INIS)

    Carretero-González, R; Frantzeskakis, D J; Kevrekidis, P G

    2008-01-01

    The aim of this review is to introduce the reader to some of the physical notions and the mathematical methods that are relevant to the study of nonlinear waves in Bose–Einstein condensates (BECs). Upon introducing the general framework, we discuss the prototypical models that are relevant to this setting for different dimensions and different potentials confining the atoms. We analyse some of the model properties and explore their typical wave solutions (plane wave solutions, bright, dark, gap solitons as well as vortices). We then offer a collection of mathematical methods that can be used to understand the existence, stability and dynamics of nonlinear waves in such BECs, either directly or starting from different types of limits (e.g. the linear or the nonlinear limit or the discrete limit of the corresponding equation). Finally, we consider some special topics involving more recent developments, and experimental setups in which there is still considerable need for developing mathematical as well as computational tools. (invited article)

  11. Liquid-gas and solid-liquid interface: thermodynamics of capillary condensation application to a prosimetry by calorimetric measurements

    International Nuclear Information System (INIS)

    Derrien, Francois; Hartmanshenn, Olivier.

    1978-01-01

    A direct determination of the pore radii distribution is proposed using calorimetric measurements during condensation and evacuation of pores by capillary condensate. This method is independant of any gravimetric or volumetric measurement of adsorption

  12. Relaxation dynamics of a driven two-level system coupled to a Bose-Einstein condensate: application to quantum dot-dipolar exciton gas hybrid systems.

    Science.gov (United States)

    Kovalev, Vadim M; Tse, Wang-Kong

    2017-11-22

    We develop a microscopic theory for the relaxation dynamics of an optically pumped two-level system (TLS) coupled to a bath of weakly interacting Bose gas. Using Keldysh formalism and diagrammatic perturbation theory, expressions for the relaxation times of the TLS Rabi oscillations are derived when the boson bath is in the normal state and the Bose-Einstein condensate (BEC) state. We apply our general theory to consider an irradiated quantum dot coupled with a boson bath consisting of a two-dimensional dipolar exciton gas. When the bath is in the BEC regime, relaxation of the Rabi oscillations is due to both condensate and non-condensate fractions of the bath bosons for weak TLS-light coupling and pre dominantly due to the non-condensate fraction for strong TLS-light coupling. Our theory also shows that a phase transition of the bath from the normal to the BEC state strongly influences the relaxation rate of the TLS Rabi oscillations. The TLS relaxation rate is approximately independent of the pump field frequency and monotonically dependent on the field strength when the bath is in the low-temperature regime of the normal phase. Phase transition of the dipolar exciton gas leads to a non-monotonic dependence of the TLS relaxation rate on both the pump field frequency and field strength, providing a characteristic signature for the detection of BEC phase transition of the coupled dipolar exciton gas.

  13. Up-to-date prospects for development of natural gas and condensate processing in the USSR

    International Nuclear Information System (INIS)

    Gritsenko, A.I.; Tyurin, P.P.

    1991-01-01

    Three large gas processing complexes are expected to be guilt in North Kazakhstan, Western Siberia and Orenburg, in the USSR. With added low temperature emphasis on recovery of ethane, propane and butane, the operation of these complexes will hae an appreciable effect on both domestic and international markets. This paper reports that modifications of alumina and titanium oxide zeolites to new and existing Claus units will improve sulfur recovery by 3-4%. This will cut sulfur costs and improve the environment

  14. Nobel Lecture: Bose-Einstein condensation in a dilute gas, the first 70 years and some recent experiments

    International Nuclear Information System (INIS)

    Cornell, E.A.; Wieman, C.E.

    2002-01-01

    Bose-Einstein condensation, or BEC, has a long and rich history dating from the early 1920s. In this article we will trace briefly over this history and some of the developments in physics that made possible our successful pursuit of BEC in a gas. We will then discuss what was involved in this quest. In this discussion we will go beyond the usual technical description to try and address certain questions that we now hear frequently, but are not covered in our past research papers. These are questions along the lines of: How did you get the idea and decide to pursue it? Did you know it was going to work? How long did it take you and why? We will review some our favorites from among the experiments we have carried out with BEC. There will then be a brief encore on why we are optimistic that BEC can be created with nearly any species of magnetically trappable atom. Throughout this article we will try to explain what makes BEC in a dilute gas so interesting, unique, and experimentally challenging

  15. Equilibrium gas-oil ratio measurements using a microfluidic technique.

    Science.gov (United States)

    Fisher, Robert; Shah, Mohammad Khalid; Eskin, Dmitry; Schmidt, Kurt; Singh, Anil; Molla, Shahnawaz; Mostowfi, Farshid

    2013-07-07

    A method for measuring the equilibrium GOR (gas-oil ratio) of reservoir fluids using microfluidic technology is developed. Live crude oils (crude oil with dissolved gas) are injected into a long serpentine microchannel at reservoir pressure. The fluid forms a segmented flow as it travels through the channel. Gas and liquid phases are produced from the exit port of the channel that is maintained at atmospheric conditions. The process is analogous to the production of crude oil from a formation. By using compositional analysis and thermodynamic principles of hydrocarbon fluids, we show excellent equilibrium between the produced gas and liquid phases is achieved. The GOR of a reservoir fluid is a key parameter in determining the equation of state of a crude oil. Equations of state that are commonly used in petroleum engineering and reservoir simulations describe the phase behaviour of a fluid at equilibrium state. Therefore, to accurately determine the coefficients of an equation of state, the produced gas and liquid phases have to be as close to the thermodynamic equilibrium as possible. In the examples presented here, the GORs measured with the microfluidic technique agreed with GOR values obtained from conventional methods. Furthermore, when compared to conventional methods, the microfluidic technique was simpler to perform, required less equipment, and yielded better repeatability.

  16. Experimental studies on condensation of steam mixed with noncondensable gas inside the vertical tube in a pool filled with subcooled water

    International Nuclear Information System (INIS)

    Maheshwari, N.K.; Saha, D.; Sinha, R.K.; Aritomi, M.

    2003-01-01

    A passive containment cooling system with immersed condensers has been proposed as one of the alternatives for the advanced heavy water reactor (AHWR) being designed in India. The system removes residual/decay heat released into the containment through the immersed condensers kept in a pool of water following loss of coolant accident. An important aspect of the immersed condensers is the potential degradation of its performance due to the presence of noncondensable gases. Experiments are performed to obtain reliable data on condensation phenomena in presence of air. These experiments are conducted on full-scale tubes of condensers immersed in a pool of water maintaining similar conditions as in the prototype of AHWR. A method has been proposed for the determination of the local heat transfer rate using correlations given in literature. The parametric effects of air mass fraction, pressure, steam flow, etc. on condensation heat transfer in presence of noncondensable gas have been studied. The experimental results are compared with the correlations given in literature. (orig.)

  17. The free Bose gas with flowing condensate in algebraic quantum field theory

    International Nuclear Information System (INIS)

    Hein, S.

    1979-01-01

    After the definition of the Weyl-algebra as a universal C* algebra of the canonical commutation relations the author classifies the equilibrium states of the free dynamics of a Bose gas in a representation independent way starting from the Kubo-Martin-Schwinger boundary conditions. The role of the Laplace equation is studied in this connection. It is shown that states with a two-point function can be described by simple natural hydrodynamics using a precise definition of the term vortex. The transition to these states is considered regarding the thermodynamic limit. (HSI)

  18. Acoustic dew point and bubble point detector for gas condensates and reservoir fluids

    Energy Technology Data Exchange (ETDEWEB)

    Sivaraman, A.; Hu, Y.; Thomas, F. B.; Bennion, D. B.; Jamaluddin, A. K. M. [Hycal Energy Research Labs. Ltd., Calgary, AB (Canada)

    1997-08-01

    Detailed knowledge of bubblepoint and dewpoint pressures at reservoir temperature are crucial for natural gas processing, transportation, metering and utilization. This paper introduces a new acoustic dewpoint and bubblepoint detector that can be applied to a broad range of phase transitions, including very lean gas systems and opaque heavy oils. The system uses two acoustic transducers, one to stimulate and the other to detect normal mode vibrations of reservoir fluids in a small cylindrical resonator. The acoustic spectra are recorded at close intervals throughout the phase envelope, along with temperature, pressure and volume measurements, and the data is processed to obtain the specific condition of phase transition. Results of two systems, a binary mixture and live reservoir fluid, are presented. The detector system is claimed to be capable of operation in an isothermal mode with variable volume, and in a constant volume mode with variable temperatures. Interpretation of results is free of operator subjectivity; they show excellent agreement with results obtained by visual methods and equations of state calculations. 4 refs., 2 tabs., 4 figs.

  19. Fuel rod puncturing and fission gas monitoring system examination techniques

    International Nuclear Information System (INIS)

    Song, Woong Sup

    1999-02-01

    Fission gas products accumulated in irradiated fuel rod is 1-2 cm 3 in CANDU and 40-50 cm 3 in PWR fuel rod. Fuel rod puncturing and fission gas monitoring system can be used for both CANDU and PWR fuel rod. This system comprises puncturing device located at in cell part and monitoring device located at out cell part. The system has computerized 9 modes and can calculate both void volume and mass volume only single puncturing. This report describes techniques and procedure for operating fuel rod puncturing and gas monitoring system which can be play an important role in successful operation of the devices. Results obtained from the analysis can give more influence over design for fuel rods. (Author). 6 refs., 9 figs

  20. Corrosion in the wet-dry zone in a flue gas condenser; Korrosion i vaattorr zon i roekgaskondensor

    Energy Technology Data Exchange (ETDEWEB)

    Nordling, Magnus; Roemhild, Stefanie; Bergman, Gunnar

    2008-06-15

    The corrosion resistance for a number of metallic and polymeric materials, in the environment of the inlet part of a flue gas condenser for a combustion plant, has been investigated. The combustion plants have been Igelstaverket and Bristaverket, for which the fuel has been mainly waste wood and biofuels, respectively. The materials were exposed in the dry and the wet zone, and also in the transfer zone in between. The metallic materials where stainless steels of the grades 17-10-2L, 2205, SAF2507 and 254SMO, all with a through weld joint, while the polymeric materials where fibre reinforced plastics (FRP) and glass-flake applied on carbon steel. The FRP materials had been formed partly by a traditional method and partly using new types of reinforcement materials, mainly based on carbon fibre, which where located in the surface layer. Also laminate with the special reinforcement of the type 3D-fabric was investigated. The investigation showed that all the metallic materials came off good under normal operating conditions when using biofuels, while 17-10-2L did not manage when using waste wood. The welds of 2205 showed a somewhat restricted corrosion resistance, otherwise being the best choice for waste wood plants when taking the material cost into consideration. FRP, as it seems, can be used successfully in the environments studied for combustion plants using biofuels. The results also indicate that the lifetime can be improved and the maintenance reduced by doing the correct choice of laminate structure and material compared to the laminates of the common type. The laminate structure, however, has to be adjusted to fulfil the demands given by the process environment. It should also further be pointed out that the good results for the flake coatings not necessarily would be the case for real use, where the walls are exposed to a temperature gradient. Finally, a conclusion, outside the initial purpose of the project, was that the addition of ammonium sulphate in

  1. The use of radon gas techniques for earthquake prediction

    International Nuclear Information System (INIS)

    Al-Hilal, M.

    1993-01-01

    This scientific article explains the applications of radon gas measurements in water and soil for monitoring fault activities and earthquake prediction. It also emphasizes, through some worldwide examples presented from Tashkent Basin in U.S.S.R. and from San Andreas fault in U.S.A, that the use of radon gas technique in fault originated water as well as in soil gases can be considered as an important geological-tool, within the general framework of earthquake prediction because of the coherent and time anomalous relationship between the density of alpha particles due to radon decay and between the tectonic activity level along fault zones. The article also indicates, and through the practical experience of the author, to the possibility of applying such techniques in certain parts of Syria. (author). 6 refs., 4 figs

  2. EGRADATION CHARACTERISTICS OF SOME SUDANESE GRASSES AND GAS PRODUCTION TECHNIQUES

    OpenAIRE

    A.O. Idris; C. Kijora; A.M. Salih; I. Bushara; H.A.A. Elbukhary

    2012-01-01

    Eighteen plant species, three ingredients, and six diets were studied for their degradation characteristics, using gas production techniques. The palatable grasses were selected during the rainy season from the range land of Kordofan, Sudan. The ingredients were Roselle seeds, Sorghum grain and Groundnut cake. The samples were incubated for 4, 8, 12, 24, 48, 72 and 96 h, using rumen inoculum of three of the sheep used for the nylon bag. The results showed a large variation between the differe...

  3. Elusive gas. Efficient technique to crack shale gas; Ongrijpbaar gas. Efficientere techniek voor kraken schaliegas nodig

    Energy Technology Data Exchange (ETDEWEB)

    Van Velzen, T.

    2011-09-02

    Energy companies such as Shell in the United States win on a large scale shale gas . The industry has developed so rapidly that the gas price has fallen sharply. Lower production costs could take care of the price decrease, but then the extraction technology must be improved. By means of simulations the energy companies are searching for new methods. [Dutch] Energiebedrijven als Shell winnen in de Verenigde Staten op grote schaal gas uit schalie. De sector heeft zich zo snel ontwikkeld dat de gasprijs sterk is gedaald. Lagere productiekosten kunnen de prijsdaling opvangen, maar dan moet de winningstechnologie worden verbeterd. Via simulaties zoeken de energiebedrijven naar nieuwe methoden.

  4. Antimicrobial activity of silica coated silicon nano-tubes (SCSNT) and silica coated silicon nano-particles (SCSNP) synthesized by gas phase condensation.

    Science.gov (United States)

    Tank, Chiti; Raman, Sujatha; Karan, Sujoy; Gosavi, Suresh; Lalla, Niranjan P; Sathe, Vasant; Berndt, Richard; Gade, W N; Bhoraskar, S V; Mathe, Vikas L

    2013-06-01

    Silica-coated, silicon nanotubes (SCSNTs) and silica-coated, silicon nanoparticles (SCSNPs) have been synthesized by catalyst-free single-step gas phase condensation using the arc plasma process. Transmission electron microscopy and scanning tunneling microscopy showed that SCSNTs exhibited a wall thickness of less than 1 nm, with an average diameter of 14 nm and a length of several 100 nm. Both nano-structures had a high specific surface area. The present study has demonstrated cheaper, resistance-free and effective antibacterial activity in silica-coated silicon nano-structures, each for two Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration (MIC) was estimated, using the optical densitometric technique, and by determining colony-forming units. The MIC was found to range in the order of micrograms, which is comparable to the reported MIC of metal oxides for these bacteria. SCSNTs were found to be more effective in limiting the growth of multidrug-resistant Staphylococcus aureus over SCSNPs at 10 μg/ml (IC 50 = 100 μg/ml).

  5. Biomarkers of exposure to stainless steel tungsten inert gas welding fumes and the effect of exposure on exhaled breath condensate.

    Science.gov (United States)

    Riccelli, Maria Grazia; Goldoni, Matteo; Andreoli, Roberta; Mozzoni, Paola; Pinelli, Silvana; Alinovi, Rossella; Selis, Luisella; Mutti, Antonio; Corradi, Massimo

    2018-08-01

    The respiratory tract is the main target organ of the inhaled hexavalent chromium (Cr-VI) and nickel (Ni) contained in stainless steel (SS) welding fumes (WFs). The aim of this study was to investigate the Cr and Ni content of the exhaled breath condensate (EBC) of SS tungsten inert gas (TIG) welders, and relate their concentrations with oxidative stress and inflammatory biomarkers. EBC and urine from 100 SS TIG welders were collected pre-(T 0 ) and post-shift (T 1 ) on a Friday, and pre-shift (T 2 ) on the following Monday morning. Both EBC and urinary Cr concentrations were higher at T 1 (0.08 μg/L and 0.71 μg/g creatinine) and T 0 (0.06 μg/L and 0.74 μg/g creatinine) than at T 2 (below the limit of detection [LOD] and 0.59 μg/g creatinine), and EBC Ni concentrations generally remained welding also play a role in generating lung oxidative stress. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Reproductive effects of the water-accommodated fraction of a natural gas condensate in the Indo-Pacific reef-building coral Pocillopora damicornis.

    Science.gov (United States)

    Villanueva, R D; Yap, H T; Montaño, M N E

    2011-11-01

    Toxic effects of the water-accommodated fraction (WAF) of a natural gas condensate on the reproduction of the brooding coral Pocillopora damicornis were studied in short-term (24 h) laboratory experiments. Coral fragments were exposed to varying concentrations of condensate WAF during different reproductive phases: gametogenesis, early embryogenesis, and late embryogenesis (when nighttime planulation occurs). During gametogenesis, exposure to condensate WAF did not inhibit subsequent production of larvae. On the other hand, exposure to >25% WAF of gravid corals, at early and late embryogenesis, resulted in abortion and early release of larvae, respectively, with higher percentages of larvae expelled in fragments treated with higher concentrations of condensate WAF at least 3h after onset of exposure. Aborted larvae during early embryogenesis were 'premature', as they are of small size (0.06±0.03 mm³), low metamorphic competency (54%), and white in coloration, with a pale brown oral end (indicating low density of zooxanthellae). Those larvae released at the latter part of embryogenesis are bigger in size (0.22±0.08 mm³), possess 100% metamorphic competency, and are brown in coloration (high density of zooxanthellae). Aside from direct effects on reproduction, fragment mortality index was higher in samples exposed to higher concentrations of condensate WAF (>25%), hence lowering the number of potentially reproducing polyps. Altogether, exposure to >25% natural gas condensate WAF for at least 3h can potentially disrupt the replenishment of coral populations due to negative effects on reproduction and early life processes. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Method and apparatus for maintaining condensable constituents of a gas in a vapor phase during sample transport

    Science.gov (United States)

    Felix, Larry Gordon; Farthing, William Earl; Irvin, James Hodges; Snyder, Todd Robert

    2010-05-18

    A system for fluid transport at elevated temperatures having a conduit having a fluid inlet end and a fluid outlet end and at least one heating element disposed within the conduit providing direct heating of a fluid flowing through the conduit. The system is particularly suited for preventing condensable constituents of a high temperature fluid from condensing out of the fluid prior to analysis of the fluid. In addition, operation of the system so as to prevent the condensable constituents from condensing out of the fluid surprisingly does not alter the composition of the fluid.

  8. Technique for radiation treatment of exhaust gas due to combustion

    International Nuclear Information System (INIS)

    Machi, Sueo

    1978-01-01

    As the Japanese unique research in the field of preservation of environment, the technique to remove simultaneously sulphur dioxide and nitrogen oxides in exhaust gas using electron beam irradiation is noteworthy. This research was started by the experiment in the central research laboratory of Ebara Manufacturing Co., Ltd., in which it was found that the sulphur dioxide of initial concentration of 1,000 ppm was almost completely vanished when the exhaust gas of heavy oil combustion in a batch type vessel was irradiated for 9 minutes by electron beam. Based on this experiment, JAERI installed a continuous irradiation equipment with a large accelerator, and has investigated the effect of various parameters such as dose rate, irradiation temperature, total dose and agitation. This resulted in the remarkable finding that nitrogen oxides were also completely removed as well as sulphur dioxide when the exhaust gas containing both sulphur dioxide and nitrogen oxides was irradiated for a few seconds. In this case, if water of about 0.3% is added, removal rate of sulphur dioxide is greatly increased. The research group of University of Tokyo obtained other findings concerning removal rates. Then, after the pilot plant stage in Ebara Manufacturing Co., Ltd. from 1974, the test plant of exhaust gas treatment for a sintering machine, having the capacity of 3,000 Nm 3 /hr, has been constructed in Yawata Works of Nippon Steel Corp. This is now operating properly. (Wakatsuki, Y.)

  9. Impact of airway gas exchange on the multiple inert gas elimination technique: theory.

    Science.gov (United States)

    Anderson, Joseph C; Hlastala, Michael P

    2010-03-01

    The multiple inert gas elimination technique (MIGET) provides a method for estimating alveolar gas exchange efficiency. Six soluble inert gases are infused into a peripheral vein. Measurements of these gases in breath, arterial blood, and venous blood are interpreted using a mathematical model of alveolar gas exchange (MIGET model) that neglects airway gas exchange. A mathematical model describing airway and alveolar gas exchange predicts that two of these gases, ether and acetone, exchange primarily within the airways. To determine the effect of airway gas exchange on the MIGET, we selected two additional gases, toluene and m-dichlorobenzene, that have the same blood solubility as ether and acetone and minimize airway gas exchange via their low water solubility. The airway-alveolar gas exchange model simulated the exchange of toluene, m-dichlorobenzene, and the six MIGET gases under multiple conditions of alveolar ventilation-to-perfusion, VA/Q, heterogeneity. We increased the importance of airway gas exchange by changing bronchial blood flow, Qbr. From these simulations, we calculated the excretion and retention of the eight inert gases and divided the results into two groups: (1) the standard MIGET gases which included acetone and ether and (2) the modified MIGET gases which included toluene and m-dichlorobenzene. The MIGET mathematical model predicted distributions of ventilation and perfusion for each grouping of gases and multiple perturbations of VA/Q and Qbr. Using the modified MIGET gases, MIGET predicted a smaller dead space fraction, greater mean VA, greater log(SDVA), and more closely matched the imposed VA distribution than that using the standard MIGET gases. Perfusion distributions were relatively unaffected.

  10. Noble Gas Measurement and Analysis Technique for Monitoring Reprocessing Facilities

    International Nuclear Information System (INIS)

    William S. Charlton

    1999-01-01

    An environmental monitoring technique using analysis of stable noble gas isotopic ratios on-stack at a reprocessing facility was developed. This technique integrates existing technologies to strengthen safeguards at reprocessing facilities. The isotopic ratios are measured using a mass spectrometry system and are compared to a database of calculated isotopic ratios using a Bayesian data analysis method to determine specific fuel parameters (e.g., burnup, fuel type, fuel age, etc.). These inferred parameters can be used by investigators to verify operator declarations. A user-friendly software application (named NOVA) was developed for the application of this technique. NOVA included a Visual Basic user interface coupling a Bayesian data analysis procedure to a reactor physics database (calculated using the Monteburns 3.01 code system). The integrated system (mass spectrometry, reactor modeling, and data analysis) was validated using on-stack measurements during the reprocessing of target fuel from a U.S. production reactor and gas samples from the processing of EBR-II fast breeder reactor driver fuel. These measurements led to an inferred burnup that matched the declared burnup with sufficient accuracy and consistency for most safeguards applications. The NOVA code was also tested using numerous light water reactor measurements from the literature. NOVA was capable of accurately determining spent fuel type, burnup, and fuel age for these experimental results. Work should continue to demonstrate the robustness of this system for production, power, and research reactor fuels

  11. Nuclear techniques in oil and gas exploration and production

    International Nuclear Information System (INIS)

    Caldwell, R.L.; Mills, W.R. Jr.; Orr, W.L.; Allen, L.S.

    1977-01-01

    A review is given of some of the most significant new developments that have occurred during the past three years in the area of nuclear techniques applied to the exploration for and production of oil and gas deposits. Experimental and theoretical studies have been carried out aimed at improving pulsed neutron logging tools and upgrading interpretation of data from such tools. Pulsed neutron borehole generators and gamma-ray spectroscopy have been combined in carbon/oxygen logging to provide a means of determining formation oil saturation in cased holes that is independent of water salinity. Use of pulsed neutron logs in the log-inject-log technique has been tested and evaluated in several field studies. The combination of a gamma-gamma density log and a borehole gravimeter has been used to detect economically important gas accumulations at distances from a borehole that are well beyond the depth of investigation of conventional logging techniques. The depths of investigation of several commercial nuclear logging tools have been studied in laboratory investigations. Possible geological applications of natural gamma-ray spectral logs have been investigated through the study of large sample suites and in specific field applications. The extensive use of digital recording of logging data and well-site analysis by minicomputer are expected to have a significant influence on future logging programmes and logging sonde designs. The present status of stable isotope geochemistry and radioactive tracer surveys is reviewed. (author)

  12. Unit vent airflow measurements using a tracer gas technique

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D.G. [Union Electric Company, Fulton, MO (United States); Lagus, P.L. [Lagus Applied Technology, Inc., San Diego, CA (United States); Fleming, K.M. [NCS Corp., Columbus, OH (United States)

    1997-08-01

    An alternative method for assessing flowrates that does not depend on point measurements of air flow velocity is the constant tracer injection technique. In this method one injects a tracer gas at a constant rate into a duct and measures the resulting concentration downstream of the injection point. A simple equation derived from the conservation of mass allows calculation of the flowrate at the point of injection. Flowrate data obtained using both a pitot tube and a flow measuring station were compared with tracer gas flowrate measurements in the unit vent duct at the Callaway Nuclear Station during late 1995 and early 1996. These data are presented and discussed with an eye toward obtaining precise flowrate data for release rate calculations. The advantages and disadvantages of the technique are also described. In those test situations for which many flowrate combinations are required, or in large area ducts, a tracer flowrate determination requires fewer man-hours than does a conventional traverse-based technique and does not require knowledge of the duct area. 6 refs., 10 figs., 6 tabs.

  13. Bose-Einstein condensation in a general static homogeneous magnetic fieldinebreak and the effective action: The nonrelativistic ideal gas

    International Nuclear Information System (INIS)

    Toms, D.J.

    1995-01-01

    We consider the problem of Bose-Einstein condensation for a system of nonrelativistic spin-0 bosons in a space of arbitrary dimension D. A general static homogeneous magnetic field is imposed. The effective action approach and ζ-function regularization are used. If D=2δ or 2δ+1, a constant magnetic field is characterized by δ independent components. If p≤δ of these components are nonzero, the condition for Bose-Einstein condensation to occur is D-2p≥3. This means that if D=2δ, then Bose-Einstein condensation never occurs for p=δ-1 or δ. If D=2δ+1, Bose-Einstein condensation never occurs for p=δ. For D-2p≥3, Bose-Einstein condensation does occur, and we show how it may be interpreted as symmetry breaking to give a ground state which is not constant

  14. Techniques for induction of premature chromosome condensation (PCC) by Calyculin-A and micronucleus assay for biodosimetry in Vietnam

    International Nuclear Information System (INIS)

    Pham Ngoc Duy; Tran Que; Hoang Hung Tien; Bui Thi Kim Luyen; Nguyen Thi Kim Anh; Ha Thi Ngoc Lien

    2014-01-01

    The International Atomic Energy Agency (IAEA) and World Health Organization are interested in biological dosimetry method for radiation emergency medicine currently. Some cytogenetic techniques such as premature chromosome condensation (PCC) induced by Calyculin-A and micronucleus (MN) assay are necessary to develop biodosimetry in Vietnam. In this study, we optimized the condition for MN assay with 6 µg/ml Cytochalasin-B concentration and 72.5 hours for peripheral lymphocyte blood culture. The optimization for PCC method is 50 nM Calyculin-A concentration for 45 minutes peripheral lymphocyte blood treatment. For samples exposed to 3.0 Gy gamma 60 Co (dose rate 0.0916 Gy/s), the frequency of MN is 19.02 ± 0.38%, NBP is 1.95 ± 0.28%, dicentric and ring is 41.43 ± 8.12% and frag and min is 63.33 ± 5.16%. For samples exposed to 6.0 Gy gamma 60 Co (dose rate 0.0916 Gy/s), the frequency of ring-PCC is 17.73 ± 2.46%, extra unite is 218.91± 7.58%, dicentric is 83.81 ± 1.09%, ring is 10.75 ± 1.74%, fragment and minute is 193.17 ± 13.10%. MN and ring-PCC are specific marker applying for biodosimetry. (author)

  15. Melt quenching and coolability by water injection from below: Co-injection of water and non-condensable gas

    International Nuclear Information System (INIS)

    Cho, Dae H.; Page, Richard J.; Abdulla, Sherif H.; Anderson, Mark H.; Klockow, Helge B.; Corradini, Michael L.

    2006-01-01

    The interaction and mixing of high-temperature melt and water is the important technical issue in the safety assessment of water-cooled reactors to achieve ultimate core coolability. For specific advanced light water reactor (ALWR) designs, deliberate mixing of the core melt and water is being considered as a mitigative measure, to assure ex-vessel core coolability. The goal of our work is to provide the fundamental understanding needed for melt-water interfacial transport phenomena, thus enabling the development of innovative safety technologies for advanced LWRs that will assure ex-vessel core coolability. The work considers the ex-vessel coolability phenomena in two stages. The first stage is the melt quenching process and is being addressed by Argonne National Lab and University of Wisconsin in modified test facilities. Given a quenched melt in the form of solidified debris, the second stage is to characterize the long-term debris cooling process and is being addressed by Korean Maritime University via test and analyses. In this paper, experiments on melt quenching by the injection of water from below are addressed. The test section represented one-dimensional flow-channel simulation of the bottom injection of water into a core melt in the reactor cavity. The melt simulant was molten lead or a lead alloy (Pb-Bi). For the experimental conditions employed (i.e., melt depth and water flow rates), it was found that: (1) the volumetric heat removal rate increased with increasing water mass flow rate and (2) the non-condensable gas mixed with the injected water had no impairing effect on the overall heat removal rate. Implications of these current experimental findings for ALWR ex-vessel coolability are discussed

  16. Strengthening power generation efficiency utilizing liquefied natural gas cold energy by a novel two-stage condensation Rankine cycle (TCRC) system

    International Nuclear Information System (INIS)

    Bao, Junjiang; Lin, Yan; Zhang, Ruixiang; Zhang, Ning; He, Gaohong

    2017-01-01

    Highlights: • A two-stage condensation Rankine cycle (TCRC) system is proposed. • Net power output and thermal efficiency increases by 45.27% and 42.91%. • The effects of the condensation temperatures are analyzed. • 14 working fluids (such as propane, butane etc.) are compared. - Abstract: For the low efficiency of the traditional power generation system with liquefied natural gas (LNG) cold energy utilization, by improving the heat transfer characteristic between the working fluid and LNG, this paper has proposed a two-stage condensation Rankine cycle (TCRC) system. Using propane as working fluid, compared with the combined cycle in the conventional LNG cold energy power generation method, the net power output, thermal efficiency and exergy efficiency of the TCRC system are respectively increased by 45.27%, 42.91% and 52.31%. Meanwhile, the effects of the first-stage and second-stage condensation temperature and LNG vaporization pressure on the performance and cost index of the TCRC system (net power output, thermal efficiency, exergy efficiency and UA) are analyzed. Finally, using the net power output as the objective function, with 14 organic fluids (such as propane, butane etc.) as working fluids, the first-stage and second-stage condensation temperature at different LNG vaporization pressures are optimized. The results show that there exists a first-stage and second-stage condensation temperature making the performance of the TCRC system optimal. When LNG vaporization pressure is supercritical pressure, R116 has the best economy among all the investigated working fluids, and while R150 and R23 are better when the vaporization pressure of LNG is subcritical.

  17. Application of safeguards techniques to the Eurodif gas diffusion plant

    International Nuclear Information System (INIS)

    Coates, J.H.; Goens, J.R.

    1979-01-01

    The characteristic features of gas diffusion plants are such that safeguards procedures specifically suited for this technique can be proposed. The first of these features is the fact that appreciably altering the enrichment level of the plant product is not possible without making easily detectable changes either in the plant structure itself or in the movement of incoming and outgoing materials. Furthermore, because of the size of gas diffusion plants large stocks of uranium are present in them. Although inventory differences may be small in relative terms, they are large in abosolute terms and exceed the quantities of low-enriched uranium considered significant from the standpoint of safeguards. Lastly, the impossibility for economic reasons for taking a physical inventory of the plant after it has been emptied prevents a comparison of the physical inventory with the book inventory. It would therefore seem that the safeguarding of a gas diffusion plant should be focused on the movement of nuclear material between the plant and the outside world. The verification of inputs and outputs can be considered satisfactory from the safeguards standpoint as long as it is possible to make sure of the containment of the plant and of the surveillance for the purpose of preventing clandestine alterations of structure. The description of the Eurodif plant and the movement of materials planned there at present indicate that the application of such a safeguards technique to the plant should be acceptable to the competent authorities. For this purpose a monitoring area has been set aside in which the inspectors will be able to keep track of all movements between the outside world and the enrichment plant

  18. Chemical composition and the nutritive value of pistachio epicarp (in situ degradation and in vitro gas production techniques

    Directory of Open Access Journals (Sweden)

    Somayeh Bakhshizadeh

    2014-04-01

    Full Text Available The nutritive value of pistachio epicarp (PE was evaluated by in situ and in vitro techniques. Chemical analysis indicated that PE was high in crude protein (11.30% and low in neutral detergent fiber (26.20%. Total phenols, total tannins, condensed tannins and hydrolysable tannins contents in PE were 8.29%, 4.48%, 0.49% and 3.79%, respectively. Ruminal dry matter and crude protein degradation after 48 hr incubation were 75.21% and 82.52%, respectively. The gas production volume at 48 hr for PE was 122.47 mL g-1DM. As a whole, adding polyethylene glycol (PEG to PE increased (p < 0.05 gas production volumes, organic matter digestibility and the metabolizable energy that illustrated inhibitory effect of phenolics on rumen microbial fermentation and the positive influence of PEG on digestion PE. The results showed that PE possessed potentials to being used as feed supplements.

  19. Chemical composition and the nutritive value of pistachio epicarp (in situ degradation and in vitro gas production techniques).

    Science.gov (United States)

    Bakhshizadeh, Somayeh; Taghizadeh, Akbar; Janmohammadi, Hossein; Alijani, Sadegh

    2014-01-01

    The nutritive value of pistachio epicarp (PE) was evaluated by in situ and in vitro techniques. Chemical analysis indicated that PE was high in crude protein (11.30%) and low in neutral detergent fiber (26.20%). Total phenols, total tannins, condensed tannins and hydrolysable tannins contents in PE were 8.29%, 4.48%, 0.49% and 3.79%, respectively. Ruminal dry matter and crude protein degradation after 48 hr incubation were 75.21% and 82.52%, respectively. The gas production volume at 48 hr for PE was 122.47 mL g(-1)DM. As a whole, adding polyethylene glycol (PEG) to PE increased (p gas production volumes, organic matter digestibility and the metabolizable energy that illustrated inhibitory effect of phenolics on rumen microbial fermentation and the positive influence of PEG on digestion PE. The results showed that PE possessed potentials to being used as feed supplements.

  20. Effect of Channel Geometry and Properties of a Vapor-Gas Mixture on Volume Condensation in a Flow through a Nozzle

    Science.gov (United States)

    Sidorov, A. A.; Yastrebov, A. K.

    2018-01-01

    A method of direct numerical solution of the kinetic equation for the droplet size distribution function was used for the numerical investigation of volume condensation in a supersonic vapor-gas flow. Distributions of temperature for the gas phase and droplets, degree of supersaturation, pressure, fraction of droplets by weight, the number of droplets per unit mass, and of the nucleation rate along the channel were determined. The influence of nozzle geometry, mixture composition, and temperature dependence of the mixture properties on the investigated process was evaluated. It has been found that the nozzle divergence angle determines the vapor-gas mixture expansion rate: an increase in the divergence angle enhances the temperature decrease rate and the supersaturation degree raise rate. With an increase or decrease in the partial pressure of incondensable gas, the droplet temperature approaches the gas phase temperature or the saturation temperature at the partial gas pressure, respectively. A considerable effect of the temperature dependence of the liquid surface tension and properties on gas phase parameters and the integral characteristics of condensation aerosol was revealed. However, the difference in results obtained with or without considering the temperature dependence of evaporation heat is negligible. The predictions are compared with experimental data of other investigations for two mixtures: a mixture of heavy water vapor with nitrogen (incondensable gas) or n-nonane vapor with nitrogen. The predictions agree quite well qualitatively and quantitatively with the experiment. The comparison of the predictions with numerical results from other publications obtained using the method of moments demonstrates the usefulness of the direct numerical solution method and the method of moments in a wide range of input data.

  1. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Viegas-Pequignot, E.M.

    1981-01-01

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs [fr

  2. The Effect of Process Parameters on the Synthesis of Ti and TiO2 Nanoparticles Producted by Electromagnetic Levitational Gas Condensation

    Directory of Open Access Journals (Sweden)

    Maryam Moazeni

    2012-10-01

    Full Text Available The nanoparticles of Ti and TiO2 have attracted extensive research interest because of their diverse applications in, for instance, catalysis, energy conversion, pigment and cosmetic manufacturing and biomedical engineering. Through this project, a one-step bulk synthesis method of electromagnetic levitational gas condensation (ELGC was utilized for the synthesis of monodispersed and crystalline Ti and TiO2 nanoparticles. Within the process, the Ti vapours ascending from the high temperature levitated droplet were condensed by an argon gas stream under atmospheric pressure. The TiO2 nanoparticles were produced by simultaneous injection of argon and oxygen into the reactor. The effects of flow rate of the condensing and oxidizing gases on the size and the size distribution of the nanoparticles were investigated. The particles were characterized by scanning electron microscopy (SEM, X-ray diffraction (XRD and image analysis. The process parameters for the synthesis of the crystalline Ti and TiO2 nanoparticles were determined.

  3. Proceedings: Condenser technology conference

    International Nuclear Information System (INIS)

    Tsou, J.L.; Mussalli, Y.G.

    1991-08-01

    Seam surface condenser and associated systems performance strongly affects availability and heat rate in nuclear and fossil power plants. Thirty-six papers presented at a 1990 conference discuss research results, industry experience, and case histories of condenser problems and solutions. This report contains papers on life extension, performance improvement, corrosion and failure analysis, fouling prevention, and recommendation for future R ampersand D. The information represents recent work on condenser problems and solutions to improve the procurement, operation, and maintenance functions of power plant personnel. Several key points follow: A nuclear and a fossil power plant report show that replacing titanium tube bundles improves condenser availability and performance. One paper reports 10 years of experience with enhanced heat transfer tubes in utility condensers. The newly developed enhanced condenser tubes could further improve condensing heat transfer. A new resistance summation method improves the accuracy of condenser performance prediction, especially for stainless steel and titanium tubed condensers. Several papers describe improved condenser fouling monitoring techniques, including a review of zebra mussel issues

  4. Gas chromatographic isolation technique for compound-specific radiocarbon analysis

    International Nuclear Information System (INIS)

    Uchida, M.; Kumamoto, Y.; Shibata, Y.; Yoneda, M.; Morita, M.; Kawamura, K.

    2002-01-01

    Full text: We present here a gas chromatographic isolation technique for the compound-specific radiocarbon analysis of biomarkers from the marine sediments. The biomarkers of fatty acids, hydrocarbon and sterols were isolated with enough amount for radiocarbon analysis using a preparative capillary gas chromatograph (PCGC) system. The PCGC systems used here is composed of an HP 6890 GC with FID, a cooled injection system (CIS, Gerstel, Germany), a zero-dead-volume effluent splitter, and a cryogenic preparative collection device (PFC, Gerstel). For AMS analysis, we need to separate and recover sufficient quantity of target individual compounds (>50 μgC). Yields of target compounds from C 14 n-alkanes to C 40 to C 30 n-alkanes and approximately that of 80% for higher molecular weights compounds more than C 30 n-alkanes. Compound specific radiocarbon analysis of organic compounds, as well as compound-specific stable isotope analysis, provide valuable information on the origins and carbon cycling in marine system. Above PCGC conditions, we applied compound-specific radiocarbon analysis to the marine sediments from western north Pacific, which showed the possibility of a useful chronology tool for estimating the age of sediment using organic matter in paleoceanographic study, in the area where enough amounts of planktonic foraminifera for radiocarbon analysis by accelerator mass spectrometry (AMS) are difficult to obtain due to dissolution of calcium carbonate. (author)

  5. Antifoam Degradation Products in Off Gas and Condensate of Sludge Batch 9 Simulant Nitric-Formic Flowsheet Testing for the Defense Waste Processing Facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-14

    Ten chemical processing cell (CPC) experiments were performed using simulant to evaluate Sludge Batch 9 for sludge-only and coupled processing using the nitric-formic flowsheet in the Defense Waste Processing Facility (DWPF). Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) cycles were performed on eight of the ten. The other two were SRAT cycles only. Samples of the condensate, sludge, and off gas were taken to monitor the chemistry of the CPC experiments. The Savannah River National Laboratory (SRNL) has previously shown antifoam decomposes to form flammable organic products, (hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and propanal), that are present in the vapor phase and condensate of the CPC vessels. To minimize antifoam degradation product formation, a new antifoam addition strategy was implemented at SRNL and DWPF to add antifoam undiluted.

  6. Molecular equilibrium with condensation

    International Nuclear Information System (INIS)

    Sharp, C.M.; Huebner, W.F.

    1990-01-01

    Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated. 18 refs

  7. Les techniques de séparation de gaz par membranes Gas Separation Techniques by Membranes

    Directory of Open Access Journals (Sweden)

    Avrillon R.

    2006-11-01

    Full Text Available Deux types de membranes peuvent être utilisés pour la séparation des gaz. Les unes sont poreuses et séparent les gaz sur la base de leur masse moléculaire selon un mécanisme de diffusion de Knudsen dans des micropores. Les facteurs de séparation obtenus sont généralement trop faibles pour présenter un intérêt industriel. Les autres, appelées membranes non poreuses, mettent en oeuvre un mécanisme de dissolution-diffusion des gaz dans une fine couche de polymère dénuée de toute porosité. C'est de ces dernières que nous allons parler. Commencé il y a une vingtaine d'années, le développement de ce type de membranes a conduit aux premières applications industrielles en 1979 avec l'introduction par Monsanto des séparateurs PRISM pour la récupération d'hydrogène à partir de différents gaz de raffinerie et de pétrochimie. Après des débuts modestes par suite de la compétition avec des technologies éprouvées comme la cryogénie, l'adsorption et l'absorption, la perméation gazeuse est en train de conquérir sa place parmi les techniques de séparation de gaz. Elle est aujourd'hui l'une des techniques membranaires présentant le plus fort taux de progression (30 % par an. Après un rappel des principes de base de la perméation gazeuse on abordera successivement les points suivants : - le choix du polymère constituant la couche séparatrice, - l'élaboration des membranes à structure asymétrique présentant une peau dense et fine, - les principales applications industrielles. Cela permettra de mettre en évidence les avantages et les limitations actuelles de la perméation gazeuse et de souligner les différents domaines où les efforts de R et D peuvent amener des progrès significatifs. Principle of Gas permeation - Gas permeation is a technique for fractionating gas mixtures by using nonporous polymer membranes having a selective permeability to gas according to a dissolution-diffusion mechanism. Gas is made to pass

  8. Greenhouse gas mitigation using poultry litter management techniques in Bangladesh

    International Nuclear Information System (INIS)

    Mainali, Brijesh; Emran, Saad Been; Silveira, Semida

    2017-01-01

    Poultry activities have expanded significantly in Bangladesh in recent years. The litter generated from rural poultry farms is often dumped in low ground neighboring areas resulting in greenhouse gas emissions, as well as water and air pollution. This study estimates the GHG emissions of a typical rural layer poultry farm in Bangladesh, and identifies the GHG emissions reduction potential when poultry litter management techniques are used to produce biogas, generating electricity and bio-fertilizer. Life-cycle assessment (LCA) has been used for a systematic evaluation of GHG-emissions considering the local supply chain in a typical rural layer poultry farm. The analysis shows that the GHG-emissions at the poultry farm amount to 1735 KgCO_2_e_q/10000 eggs produced if the litter is untreated. With the installation of an anaerobic digester, the emission intensity could be reduced by 65% if the gas is used to replace LPG for cooking purposes. If 100% digested slurry is utilized as bio-fertilizer, the emissions intensity could be further reduced by 17 times compared to the case without slurry utilization. These results justify the consideration of national programs to improve conditions in poultry farms in Bangladesh. - Highlights: • This study estimates GHG-emissions reduction potential of utilizing poultry litter for energy production in a rural farm. • Energy/mass flow and GHG balances are evaluated considering the local supply chain. • On-farm activities significantly affect GHG emissions among others across the supply chain. • Biogas production and use of slurry as bio-fertilizer significantly reduces the emission intensity. • Results from LCA and sensitivity analysis have been discussed to identify key influential parameters.

  9. Large Mass Flux Differences for Opposite Flow Directions of a Condensable Gas through an Asymmetric Porous Membrane

    Czech Academy of Sciences Publication Activity Database

    Uchytil, Petr; Loimer, T.

    2014-01-01

    Roč. 470, NOV 15 (2014), s. 451-457 ISSN 0376-7388 R&D Projects: GA MŠk 7AMB12AT010; GA MŠk(CZ) 7AMB14AT011 Institutional support: RVO:67985858 Keywords : condensation * vapor permeation * asymmetric membrane s Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 5.056, year: 2014

  10. Bose condensates make quantum leaps and bounds

    International Nuclear Information System (INIS)

    Castin, Y.; Dum, R.; Sinatra, A.

    1999-01-01

    Since the first observation in 1995 of Bose-Einstein condensation in dilute atomic gases, atomic physicists have made extraordinary progress in understanding this unusual quantum state of matter. BOSE-EINSTEIN condensation is a macroscopic quantum phenomenon that was first predicted by Albert Einstein in the 1920s, at a time when quantum theory was still developing and was being applied to microscopic systems, such as individual particles and atoms. Einstein applied the new concept of Bose statistics to an ideal gas of identical atoms that were at thermal equilibrium and trapped in a box. He predicted that at sufficiently low temperatures the particles would accumulate in the lowest quantum state in the box, giving rise to a new state of matter with many unusual properties. The crucial point of Einstein's model is the absence of interactions between the particles in the box. However, this makes his prediction difficult to test in practice. In most real systems the complicating effect of particle interactions causes the gas to solidify well before the temperature for Bose-Einstein condensation is reached. But techniques developed in the past four years have allowed physicists to form Bose-Einstein condensates for a wide range of elements. In this article the authors describe the latest advances in Bose-Einstein condensation. (UK)

  11. Recovery enhancement at the later stage of supercritical condensate gas reservoir development via CO2 injection: A case study on Lian 4 fault block in the Fushan sag, Beibuwan Basin

    Directory of Open Access Journals (Sweden)

    Wenyan Feng

    2016-11-01

    Full Text Available Lian 4 fault block is located in the northwest of Fushan sag, Beibuwan Basin. It is a high-saturated condensate gas reservoir with rich condensate oil held by three faults. In order to seek an enhanced condensate oil recovery technology that is suitable for this condensate gas reservoir at its later development stage, it is necessary to analyze its reserve producing degree and remaining development potential after depletion production, depending on the supercritical fluid phase behavior and depletion production performance characteristics. The supercritical fluid theories and multiple reservoir engineering dynamic analysis methods were adopted comprehensively, such as dynamic reserves, production decline, liquid-carrying capacity of a production well, and remaining development potential analysis. It is shown that, at its early development stage, the condensate in Lian 4 fault block presented the features of supercritical fluid, and the reservoir pressure was lower than the dew point pressure, so retrograde condensate loss was significant. Owing to the retrograde condensate effect and the fast release of elastic energy, the reserve producing degree of depletion production is low in Lian 4 fault block, and 80% of condensate oil still remains in the reservoir. So, the remaining development potential is great. The supercritical condensate in Lian 4 fault block is of high density. Based on the optimization design by numerical simulation of compositional model, it is proposed to inject CO2 at the top and build up pressure by alternating production and injection, so that the secondary gas cap is formed while the gravity-stable miscible displacement is realized. In this way, the recovery factor of condensate reservoirs can be improved by means of the secondary development technology.

  12. Analysis of heat and mass transfer to determine heat loss and the rate of condensation of the MVSTs off-gas ducts

    International Nuclear Information System (INIS)

    Ebadian, M.A.; Yang, G.; Bigzadeh, E.; Walker, J.F.; Abraham, T.J.

    1992-01-01

    Reduction of the existing nuclear waste in the Melton Valley Storage Tanks (MVSTs) at the Oak Ridge National Laboratory (ORNL) is of utmost concern to the scientists at this facility. This paper provides proof that a combination of vault heating, sparged air heating, and prevention of condensation is the best alternative to achieve this goal. Therefore, in this study a general system of mathematical equations has been developed taking into account all of the parameters affecting evaporation and condensation. This evaporation process has been analyzed by the careful modeling of a bubble chain through the extremely viscous, radioactive liquid contained in the storage tanks. This paper discusses in detail the evaporation procedure using bubble formation, air velocity, and determining the rate at which this liquid waste can be removed from the MVSTs by evaporation under different conditons of the sparging air. An additional objective is to study the heating/cooling of the condensation process of the off-gas piping inside the vault. A laboratory scale model has also been assembled for this purpose at ORNL to verify the accuracy of the mathematical modeling. A comparison of the experimental findings with the mathematical modeling shows excellent agreement. (orig.)

  13. Method of flash evaporation and condensation – heat pump for deep cooling of coal-fired power plant flue gas: Latent heat and water recovery

    International Nuclear Information System (INIS)

    Li, Yuzhong; Yan, Min; Zhang, Liqiang; Chen, Guifang; Cui, Lin; Song, Zhanlong; Chang, Jingcai; Ma, Chunyuan

    2016-01-01

    Highlights: • A method is developed for deep cooling of flue gas in coal-fired boilers. • The method can recover both latent heat and water from flue gas. • The method utilizes FGD scrubber as a deep cooling exchanger. • The method adopts the direct heat exchange mode to avoid the corrosion problem. - Abstract: Flue gas waste heat recovery and utilization is an efficient means to improve the energy efficiency of coal-fired power plants. At present, the surface corrosion and fouling problems of heat exchanger hinder the development of flue gas deep cooling. In this study, a novel flue gas deep cooling method that can reduce flue gas temperature below the dew point of vapor to recover latent heat and obtain clean water simultaneously is proposed to achieve improved energy efficiency. The heat transfer mode of this method is the direct contact mode, which takes the scrubber, e.g. the flue gas desulfurization (FGD) scrubber, as the deep cooling exchanger. The flash evaporation and condensation (FEC) device and heat pump (HP) are utilized to provide low-temperature medium, such as FGD slurry or water, for washing and deep cooling flue gas, to collect recovered water, and to absorb recovered waste heat. This method is called as the FEC–HP method. This paper elaborated on two optional models of the proposed method. The mechanism for recovering heat and water was also analyzed using the customized flue gas humidity chart, and the method to quantitate recovered heat and water, as well as the results of the case of a 300 MW coal-fired generator set were provided. Net present value calculations showed that this method is profitable in the scenario of burning high-water-content coals. Several potential advantages of this method and suggestions for practical application were also discussed.

  14. Technical review of the high energy gas stimulation technique

    Energy Technology Data Exchange (ETDEWEB)

    Haney, B.; Cuthill, D. [Computalog Ltd., Calgary, AB (Canada)

    1997-08-01

    High Energy Gas Stimulation (HEGS) or propellant stimulation is a process that enhances production of oil wells by decreasing wellbore damage and increasing near wellbore permeability. The technique has been used on about 7,000 wells with varying results. The HEGS tool is a cast cylinder of solid rocket propellant with a central ignition system. The propellant is fired and as it burns it produces a pressure load on the formation, increasing fracture volume which enhances the flow channels. Background information on the development and application of this stimulation technique was provided. The introduction of fractures around a wellbore is dependent on the pressure loading rate and the dynamic response of the rock. Propellant stimulation relies on controlling the pressure-time behaviour to maximize fracture growth by fluid pressurization. The process is composed of 3 sequential phases: (1) wellbore pressurization, (2) fracture initiation, and (3) fracture extension. A full description of each of these phases was provided. Geologic and well-tool factors that have a significant influence on the fracturing process such as in-situ stress, natural fractures and flaws, formation mechanical properties, formation fluid and flow properties, formation thermal properties, and wellbore, tool, and tamp configuration, were also reviewed. The many applications for HEGS were presented. It was emphasized that the success of HEGS is dependent on pre-stimulation problem evaluation and on proper charge design. Since HEGS will decrease near-wellbore restrictions and initiate formation breakdown, it should only be used in cases where this will be beneficial to the well. Careful attention to engineering will optimize results. 21 refs., 13 figs.

  15. Studies on the self-catalyzed Knoevenagel condensation, characterization, DPPH radical scavenging activity, cytotoxicity, and molecular properties of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones using single crystal XRD and DFT techniques

    Science.gov (United States)

    Suresh Kumar, G. S.; Antony Muthu Prabhu, A.; Bhuvanesh, N.

    2014-10-01

    We have studied the self-catalyzed Knoevenagel condensation, spectral characterization, DPPH radical scavenging activity, cytotoxicity, and molecular properties of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones using single crystal XRD and DFT techniques. In the absence of any catalyst, a series of novel 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones were synthesized using Meldrum’s acid and formylphenoxyaliphatic acid(s) in water. These molecules are arranged in the dimer form through intermolecular H-bonding in the single crystal XRD structure. Compounds have better DPPH radical scavenging activity and cytotoxicity against A431 cancer cell line. The optimized molecular structure, natural bond orbital analysis, electrostatic potential map, HOMO-LUMO energies, molecular properties, and atomic charges of these molecules have been studied by performing DFT/B3LYP/3-21G(*) level of theory in gas phase.

  16. CO2 capture by Condensed Rotational Separation

    NARCIS (Netherlands)

    Benthum, van R.J.; Kemenade, van H.P.; Brouwers, J.J.H.; Golombok, M.

    2010-01-01

    Condensed Rotational Separation (CRS) technology is a patented method to upgrade gas mixtures. A novel application is thecapture of CO2 from coal-combustion fired power stations: Condensed Contaminant Centrifugal Separation in Coal Combustion(C5sep). CRS involves partial condensation of a gas

  17. Method and apparatus for controlled condensation isotope separation

    International Nuclear Information System (INIS)

    Sullivan, J.A.; Lee, J.T. Jr.; Kim, K.C.

    1981-01-01

    The invention provides a method for producing controlled homogeneous condensation of a molecular feed gas containing several isotopes. The feed gas flows at supersonic rates through an expansion nozzle under conditions at which the gas would normally condense. The gas is irradiated with laser radiation of a wavelength that selectively excites those molecules in the feed gas that contain a particular isotope, thus preventing their condensation. Condensate particles may be aerodynamically separated from the flowing gas stream

  18. Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces.

    Science.gov (United States)

    Spezia, Riccardo; Martínez-Nuñez, Emilio; Vazquez, Saulo; Hase, William L

    2017-04-28

    In this Introduction, we show the basic problems of non-statistical and non-equilibrium phenomena related to the papers collected in this themed issue. Over the past few years, significant advances in both computing power and development of theories have allowed the study of larger systems, increasing the time length of simulations and improving the quality of potential energy surfaces. In particular, the possibility of using quantum chemistry to calculate energies and forces 'on the fly' has paved the way to directly study chemical reactions. This has provided a valuable tool to explore molecular mechanisms at given temperatures and energies and to see whether these reactive trajectories follow statistical laws and/or minimum energy pathways. This themed issue collects different aspects of the problem and gives an overview of recent works and developments in different contexts, from the gas phase to the condensed phase to excited states.This article is part of the themed issue 'Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces'. © 2017 The Author(s).

  19. Water Condensation

    DEFF Research Database (Denmark)

    Jensen, Kasper Risgaard; Fojan, Peter; Jensen, Rasmus Lund

    2014-01-01

    The condensation of water is a phenomenon occurring in multiple situations in everyday life, e.g., when fog is formed or when dew forms on the grass or on windows. This means that this phenomenon plays an important role within the different fields of science including meteorology, building physics......, and chemistry. In this review we address condensation models and simulations with the main focus on heterogeneous condensation of water. The condensation process is, at first, described from a thermodynamic viewpoint where the nucleation step is described by the classical nucleation theory. Further, we address...

  20. Green Gas. An overview od innovative techniques and suppliers; Groen Gas. Een overzicht van innovatieve technieken en leveranciers

    Energy Technology Data Exchange (ETDEWEB)

    Van Dorp, R.

    2013-04-15

    An overview is given of all (innovative) techniques in the whole biogas chain, from biomass to the use of biogas or green gas. Each technique is supplemented with a list of suppliers and links to websites [Dutch] Een overzicht wordt gegeven van alle (innovatieve) technieken over de gehele biogasketen, van biomassa tot toepassing van biogas of groen gas. Elke techniek is aangevuld met een lijst van leveranciers en links naar websites.

  1. A Safe and Efficient Technique for the Production of HCl/DCl Gas

    Science.gov (United States)

    Mayer, Steven G.; Bard, Raymond R.; Cantrell, Kevin

    2008-01-01

    We present a safe and efficient technique to generate HCl/DCl gas for use in the classic physical chemistry experiment that introduces students to ro-vibrational spectroscopy. The reaction involves thionyl chloride and a mixture of water and deuterium oxide to produce HCl/DCl gas with SO[subscript 2] gas as a byproduct. The entire reaction is…

  2. Fundamental study on repairing technique for cracked or damaged parts of structures by cold gas dynamic spray technique

    International Nuclear Information System (INIS)

    Ogawa, Kazuhiro; Amao, Satoshi; Ichikawa, Yuji; Shoji, Tetsuo

    2008-01-01

    This study proposes an innovative technique for repairing of cracked or damaged parts of structures, such as nuclear or thermal power plants, by means of cold gas dynamic spray (CS) technique. In the case of generation of cracks etc. in the structure, the cracks can be repaired by welding. However, the welding spends considerable time on repair, and also needs special skills. The CS technique is known as a new technique not only for coatings but also for thick depositions. It has many advantages, i.e. dense deposition, high deposition rate and low oxidation. Therefore, it has a possibility to apply the CS technique instead of welding to repair the cracks etc. In this study, the cold gas dynamic spray technique as a new repairing technique for some structures is introduced. (author)

  3. Thermodynamic measurement of the sound velocity of a Bose gas across the transition to Bose–Einstein condensation

    Science.gov (United States)

    Fritsch, A. R.; Tavares, P. E. S.; Vivanco, F. A. J.; Telles, G. D.; Bagnato, V. S.; Henn, E. A. L.

    2018-05-01

    We present an alternative method for determining the sound velocity in atomic Bose–Einstein condensates, based on thermodynamic global variables. The total number of trapped atoms was as a function of temperature carefully studied across the phase transition, at constant volume. It allowed us to evaluate the sound velocity resulting in consistent values from the quantum to classical regime, in good agreement with previous results found in literature. We also provide some insight about the dominant sound mode (thermal or superfluid) across a wide temperature range.

  4. Risk management technique for liquefied natural gas facilities

    Science.gov (United States)

    Fedor, O. H.; Parsons, W. N.

    1975-01-01

    Checklists have been compiled for planning, design, construction, startup and debugging, and operation of liquefied natural gas facilities. Lists include references to pertinent safety regulations. Methods described are applicable to handling of other hazardous materials.

  5. Computed Tomography Colonography Technique: The Role of Intracolonic Gas Volume

    Directory of Open Access Journals (Sweden)

    Patrick D. McLaughlin

    2013-01-01

    Full Text Available Introduction. Poor distention decreases the sensitivity and specificity of CTC. The total volume of gas administered will vary according to many factors. We aim to determine the relationship between the volume of retained gas at the time of image acquisition and colonic distention and specifically the presence of collapsed bowel segments at CTC. Materials and Methods. All patients who underwent CTC over a 12-month period at a single institution were included in the study. Colonic luminal distention was objectively scored by 2 radiologists using an established 4-point scale. Quantitative analysis of the volume of retained gas at the time of image acquisition was conducted using the threshold 3D region growing function of OsiriX. Results. 108 patients were included for volumetric analysis. Mean retained gas volume was 3.3 L. 35% (38/108 of patients had at least one collapsed colonic segment. Significantly lower gas volumes were observed in the patients with collapsed colonic segments when compared with those with fully distended colons 2.6 L versus 3.5 L (P=0.031. Retained volumes were significantly higher for the 78% of patients with ileocecal reflux at 3.4 L versus 2.6 L without ileocecal reflux (P=0.014. Conclusion. Estimation of intraluminal gas volume at CTC is feasible using image segmentation and thresholding tools. An average of 3.5 L of retained gas was found in diagnostically adequate CTC studies with significantly lower mean gas volume observed in patients with collapsed colonic segments.

  6. Possible techniques for decontamination of natural gas from gas wells stimulated by a nuclear explosion

    Energy Technology Data Exchange (ETDEWEB)

    Wethington, Jr, John A [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    Decontamination of the products from gas wells stimulated by nuclear explosions requires the removal of T, present as HT, CH{sub 3}T, C{sub 2}H{sub 5}T, etc., and {sup 85}Kr from the production stream. Flaring of large volumes of gas from the Gasbuggy well led to the replacement of radioactive cavity gas with inactive formation gas, but this would not be a satisfactory production procedure because it releases T and {sup 85}Kr into the atmosphere and wastes large amounts of product gas. Exchange reactions appear to offer promise for removing the tritium. For example, water or steam flowing countercurrent to tritiated gas in the presence of a suitable catalyst can participate in the exchange reactions CH{sub 3}T + H{sub 2}O {r_reversible} CH{sub 4} + HTO, HT + H{sub 2}O {r_reversible} H{sub 2} + HTO, resulting in the transfer of T from gas into water. Other possibilities for utilizing exchange reactions include exchange of the gas with ethylene glycol used in the gas dryer, with silicate rocks introduced into the gas stream, or with a countercurrent stream of NH{sub 3} or H{sub 2}S. As another approach, use of the contaminated gas for the manufacture of ammonia synthesis gas has potential for removal of both T and {sup 85}Kr. (author)

  7. Investigation of variable compositions on the removal of technetium from Hanford Waste Treatment Plant low activity waste melter off-gas condensate simulant

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, John M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-03-29

    The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the offgas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter, so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.

  8. Vortices in trapped Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Jackson, B.

    2000-09-01

    In this thesis we solve the Gross-Pitaevskii equation numerically in order to model the response of trapped Bose-Einstein condensed gases to perturbations by electromagnetic fields. First, we simulate output coupling of pulses from the condensate and compare our results to experiments. The excitation and separation of eigenmodes on flow through a constriction is also studied. We then move on to the main theme of this thesis: the important subject of quantised vortices in Bose condensates, and the relation between Bose-Einstein condensation and superfluidity. We propose methods of producing vortex pairs and rings by controlled motion of objects. Full three-dimensional simulations under realistic experimental conditions are performed in order to test the validity of these ideas. We link vortex formation to drag forces on the object, which in turn is connected with energy transfer to the condensate. We therefore argue that vortex formation by moving objects is intimately related to the onset of dissipation in superfluids. We discuss this idea in the context of a recent experiment, using simulations to provide evidence of vortex formation in the experimental scenario. Superfluidity is also manifest in the property of persistent currents, which is linked to vortex stability and dynamics. We simulate vortex line and ring motion, and find in both cases precessional motion and thermodynamic instability to dissipation. Strictly speaking, the Gross-Pitaevskii equation is valid only for temperatures far below the BEC transition. We end the thesis by describing a simple finite-temperature model to describe mean-field coupling between condensed and non-condensed components of the gas. We show that our hybrid Monte-Carlo/FFT technique can describe damping of the lowest energy excitations of the system. Extensions to this model and future research directions are discussed in the conclusion. (author)

  9. Nanoporous gold synthesized by plasma-assisted inert gas condensation: room temperature sintering, nanoscale mechanical properties and stability against high energy electron irradiation

    Science.gov (United States)

    Weyrauch, S.; Wagner, C.; Suckfuell, C.; Lotnyk, A.; Knolle, W.; Gerlach, J. W.; Mayr, S. G.

    2018-02-01

    With a plasma assisted gas condensation system it is possible to achieve high-purity nanoporous Au (np-Au) structures with minimal contaminations and impurities. The structures consist of single Au-nanoparticles, which partially sintered together due to their high surface to volume ratio. Through electron microscopy investigations a porosity  >50% with ligament sizes between 20-30 nm was revealed. The elastic modulus of the np-Au was determined via peak force quantitative nanomechanical mapping and resulted in values of 7.5  ±  1.5 GPa. The presented structures partially sintered at room temperature, but proved to be stable to electron irradiation with energies of 7 MeV up to doses of 100 MGy. The electron irradiation stability opens the venue for electron assisted functionalization with biomolecules.

  10. Evaluation of the PRHRS Performance Degradation due to Non-Condensable Gas for the Small and Medium Reactor using MARS-KS code

    International Nuclear Information System (INIS)

    Kim, Sook Kwan; Sim, Suk Ku; Park, Ju Yeop; Seol, Kwang Won; Ryu, Yong Ho

    2011-01-01

    The effect of non-condensable gas on the performance of PRHRS (Passive Residual Heat Removal System) of the Small and Medium Reactor(SMR) was evaluated during a loss of flow event. Since the TMI accident in 1979, the passive systems have been considered in the advanced reactors as a feature of design improvement because the passive system simplifies the system and thus increases the reliability of the system. The Westinghouse received the design certification from the USNRC for the AP600 and AP1000 passive type pressurized water reactors. The APR+ under development by KEPCO considers the use of PAFS (Passive Auxiliary Feedwater System). And the PRHRS is adopted as a passive secondary heat removal system for the SMART (System-integrated Modular Advanced ReacTor)

  11. Prediction of mineral scale formation in wet gas condensate pipelines and in MEG (mono ethylene glycol) regeneration plants

    Energy Technology Data Exchange (ETDEWEB)

    Sandengen, Kristian

    2006-12-20

    Gas hydrate formation is a serious problem in the oil and gas industry, since its formation can plug wells and prevent production. The gas hydrate is a crystalline solid with a natural gas molecule surrounded by a cage of water molecules. It forms at high pressures and low temperatures. This is a problem for offshore gas wells, where the temperature is low in transport lines from well to the production facilities. Mono Ethylene Glycol (MEG) is commonly used as hydrate inhibitor. Classified as a thermodynamic inhibitor, this additive functions just as antifreeze in an automotive radiator. When producing oil and gas there will in most cases also be produced some water, which can contain dissolved salts. These salts may precipitate and they tend to deposit on surfaces. Deposition of inorganic minerals from brine is called scale. Generally MEG has the adverse effect of lowering the solubility of most salts. A common method to prevent corrosion in flow lines is to increase pH by adding basic agents (e.g. NaOH, NaHCO{sub 3}) to the MEG stream. In such cases, carbonate salts are particularly troublesome since an increase in pH by one unit, will reduce the solubility by two orders of magnitude. Thus there will be a trade off between good corrosion protection (high pH) and scale control (low pH). The aim of this work has been to develop a model that can predict mineral solubility in the presence of MEG. Experimental solubility data, together with thermodynamic data taken from literature, have been utilized to construct empirical functions for the influence of MEG on mineral scale formation. These functions enabled the expansion of an already existing aqueous scale model into a model valid for water+MEG mixed solutions. The aqueous scale model combines an equation of state (gas+oil phase) with the Pitzer ion interaction model (water phase) to describe the multiphase behaviour of gas-oil-water systems. This work summarizes the theoretical foundation and proposes how to work

  12. In-Vitro gas production technique as for feed evaluation: volume of gas production and feed degradability

    International Nuclear Information System (INIS)

    Asih Kurniawati

    2007-01-01

    In-vitro gas production technique can be used to predict feed quality. The effect of molasses supplementation as a source of degradable carbohydrate to protein source red clover silage has been done using this technique. Data showed there were positive correlation between total volume gas produced and feed degradability (r = 0.96), between total volume gas produced and microbial biomass (r = 0,96). Dry matter degradability, dry matter degraded, microbial biomass production and efficiency of nitrogen utilization, highly significant (P<0,01) increased due to increasing of degradable carbohydrate. The addition of 0.3 g molasses gave the best result whereas the addition of 0.15 g and 0.225 g have better effect than 0.0625 g molasses addition and red clover only. This result suggested that In-vitro production technique can be used as tool for feed evaluation. (author)

  13. Bose condensation in (random traps

    Directory of Open Access Journals (Sweden)

    V.A. Zagrebnov

    2009-01-01

    Full Text Available We study a non-interacting (perfect Bose-gas in random external potentials (traps. It is shown that a generalized Bose-Einstein condensation in the random eigenstates manifests if and only if the same occurs in the one-particle kinetic-energy eigenstates, which corresponds to the generalized condensation of the free Bose-gas. Moreover, we prove that the amounts of both condensate densities are equal. This statement is relevant for justification of the Bogoliubov approximation} in the theory of disordered boson systems.

  14. Comparing and assessing different measurement techniques for mercury in coal systhesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, D.P.; Richardson, C.F. [Radian Corporation, Austin, TX (United States)

    1995-11-01

    Three mercury measurement techniques were performed on synthesis gas streams before and after an amine-based sulfur removal system. The syngas was sampled using (1) gas impingers containing a nitric acid-hydrogen peroxide solution, (2) coconut-based charcoal sorbent, and (3) an on-line atomic absorption spectrophotometer equipped with a gold amalgamation trap and cold vapor cell. Various impinger solutions were applied upstream of the gold amalgamation trap to remove hydrogen sulfide and isolate oxidized and elemental species of mercury. The results from these three techniques are compared to provide an assessment of these measurement techniques in reducing gas atmospheres.

  15. Gas absorption technique by half-dry method

    Energy Technology Data Exchange (ETDEWEB)

    Nakago, K; Haseba, S

    1974-11-19

    The removal or recovery of nitrogen oxides and sulfur oxides by chemisorption using sodium chlorite or sodium hypochlorite solutions is described. The sorption tower consists of a packed layer of porous carrier such as alumina, silica gel or zeolite, gas inlet and outlet valves, inlet and outlet valves connected to the reaction solution tank, an inlet valve from the regeneration solution tank, and an outlet valve to a separatory device where reaction products, unreacted reaction solution, and regeneration solution are separated and returned to corresponding tanks. The carrier is immersed in a reaction solution, and excessive reaction solution is drained back to the tank. Then the gas valves are opened for chemisorption removal of NOx and SOx. Finally, the reaction product on the carrier is removed with the regeneration solution. More than two towers are placed in a series for more complete removal of the designated gases.

  16. Development of detection techniques for the Swedish noble gas sampler

    International Nuclear Information System (INIS)

    Ringbom, A.

    1998-11-01

    A short review on the radioactive properties of noble gas isotopes relevant for monitoring of nuclear activities is given, together with a brief discussion of the existing systems for detection of radioactive noble gases. A 4π detection system to be used in the automatic version of the Swedish noble gas sampling device is described. Monte Carlo calculations of the total gamma and beta efficiency for different detector designs have been performed, together with estimates of the resulting minimum detectable concentration (MDC). The estimated MDC values for detection of the 133g Xe 81 keV and the 135g Xe 250 keV gamma lines are around 0.3 mBq/m 3 in both cases. This is a factor of three lower than the detection limit required for a sampling station in the Comprehensive Nuclear-Test-Ban Treaty monitoring network. The possibility to modify the system to detect 85 Kr is also discussed

  17. Evaluation of the Modern State of Water Ecosystems and the Issues with Protecting Biological Resources During Development of the Kruzenshternskoye Gas Condensate Field

    Directory of Open Access Journals (Sweden)

    Vladimir Dmitrievich Bogdanov

    2015-09-01

    Full Text Available In the article, the results of the studies of the present state of freshwater ecosystems and their biotic components in the western part of the Yamal Peninsula are presented. Based on the evaluation of the structure of the communities of phytoplankton, zooplankton, benthos and whitefishes, the range of the problems related to the protection of biological resources at the development of the Kruzenshternskoye gas field is defined. Data on species composition and quantitative indicators of hydrobionts of different types of waterbodies and watercourses in the lower reaches of the Mordyyakha and Naduyyakha rivers basins are the basis for environmental monitoring of water objects at development and exploitation of the Kruzenshternskoye gas field. According to the monitoring program, evaluation of the fish fauna state and their food base on the territory of the Kruzenshternskoye gas condensate field (GCF, is present. The zones of rivers deltas are the most important areas of the salmonid and whitefishes valuable fish species feeding at the territory of Kruzenshternskoye GCF. In the cases where complete demolish of waterbodies and watercourses for construction of facilities for GCF does not occur, changes of quantitative and qualitative characteristics of communities of hydrobionts after cease of works are reversible. River ecosystems are restored within a more short period of time in comparison to lacustrine ones. On the basis of conducted comprehensive studies, the proposals for the protection of fisheries resources and monitoring of aquatic ecosystems are reported. Recommendations for reducing the anthropogenic impact on aquatic ecosystems in the development period are presented. The results of the investigation were used in the designing the environmental protection part of the Kruzenshternskoye deposit project. At present, the disturbances in the territory of Kruzenshternskoye deposit of gas does not impact the aquatic ecosystems

  18. Plan of gas; the technique of transforming oil pipelines into gas pipeline

    International Nuclear Information System (INIS)

    Carta Petrolera

    1998-01-01

    The discovery, development and commercialization of a high one number of gas deposits with big reserves, guided to establish the National Plan, for massive use for gas, whose social objective is the of arriving with this clean and economic fuel to all the places of the country

  19. Development of the charcoal adsorption technique for determination of radon content in natural gas

    International Nuclear Information System (INIS)

    Paewpanchon, P.; Chanyotha, S.

    2017-01-01

    A technique for the determination of the radon concentration in natural gas using charcoal adsorption has been developed to study the effects of parameters that influence the adsorption efficiency of radon onto activated charcoal. Several sets of experiments were conducted both in the laboratory and in an actual natural gas field for comparison. The results show that the adsorption capability of radon onto activated charcoal varies inversely with temperature, hydrocarbon concentration and the humidity contained within the natural gas. A technique utilizing dry ice as a coolant was found to be the most effective for trapping radon in natural gas samples at the production site. A desiccant can be used to remove moisture from the sampling gas. The technique described here increases the adsorption efficiency of activated charcoal by 10-20% compared to our previous study. (authors)

  20. DEVELOPMENT OF THE CHARCOAL ADSORPTION TECHNIQUE FOR DETERMINATION OF RADON CONTENT IN NATURAL GAS.

    Science.gov (United States)

    Paewpanchon, P; Chanyotha, S

    2017-11-01

    A technique for the determination of the radon concentration in natural gas using charcoal adsorption has been developed to study the effects of parameters that influence the adsorption efficiency of radon onto activated charcoal. Several sets of experiments were conducted both in the laboratory and in an actual natural gas field for comparison. The results show that the adsorption capability of radon onto activated charcoal varies inversely with temperature, hydrocarbon concentration and the humidity contained within the natural gas. A technique utilizing dry ice as a coolant was found to be the most effective for trapping radon in natural gas samples at the production site. A desiccant can be used to remove moisture from the sampling gas. The technique described here increases the adsorption efficiency of activated charcoal by 10-20% compared to our previous study. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Diagnostic significance of gas distension technique of the stomach with gas-forming agent on CT scan of stomach cancer

    International Nuclear Information System (INIS)

    Rho, Tae Jin; Song, Chang June; Choi, Joong Chan; Park, Cheong Hee; Cho, June Sik; Rhee, Byung Chull

    1988-01-01

    CT is a valuable method for preoperative staging of patients with stomach cancers. However, in patients with poor distension of the stomach and scanty fat between the stomach and adjacent organs, CT findings may indicate a false impression of gastric wall thickening and cannot provide the precise extent of stomach cancer. We studied the usefulness of gastric distension by gas-forming agent in 28 cases of pathologically confirmed gastric cancers on CT. Comparative analysis between CT findings and surgical pathologic findings was done in 22 cases who underwent surgery. The results were as follows; 1. Conventional CT failed to define the wall thickening or masses of the stomach, in 14 cases of 23 advanced gastric cancers, while CT with gas distension technique allowed good visualization in all advanced gastric cancers. 2. In 2 cases of 5 early gastric cancers, CT with gas distension technique could detect focal thickening of the gastric wall, even less than 1cm thickness. 3. Among 13 cases with indistinguishable border between stomach and liver on conventional CT, 7 cases were diagnosed as negative invasion on CT with gas distension technique and 5 cases of these were confirmed by surgery. 4. Among 11 cases with indistinguishable border between stomach and pancreas on conventional CT, 3 cases were diagnosed as negative invasion on CT with gas distension technique, all of which were confirmed by surgery. 5. There was no significant difference between conventional CT and CT with gas distension technique of the stomach to diagnose invasion into transverse colon, transverse colon, transverse mesocolon, lymph node metastasis, and various distant metastasis.

  2. Diagnostic significance of gas distension technique of the stomach with gas-forming agent on CT scan of stomach cancer

    Energy Technology Data Exchange (ETDEWEB)

    Rho, Tae Jin; Song, Chang June; Choi, Joong Chan; Park, Cheong Hee; Cho, June Sik; Rhee, Byung Chull [Chungnam National University College of Medicine, Dajeon (Korea, Republic of)

    1988-10-15

    CT is a valuable method for preoperative staging of patients with stomach cancers. However, in patients with poor distension of the stomach and scanty fat between the stomach and adjacent organs, CT findings may indicate a false impression of gastric wall thickening and cannot provide the precise extent of stomach cancer. We studied the usefulness of gastric distension by gas-forming agent in 28 cases of pathologically confirmed gastric cancers on CT. Comparative analysis between CT findings and surgical pathologic findings was done in 22 cases who underwent surgery. The results were as follows; 1. Conventional CT failed to define the wall thickening or masses of the stomach, in 14 cases of 23 advanced gastric cancers, while CT with gas distension technique allowed good visualization in all advanced gastric cancers. 2. In 2 cases of 5 early gastric cancers, CT with gas distension technique could detect focal thickening of the gastric wall, even less than 1cm thickness. 3. Among 13 cases with indistinguishable border between stomach and liver on conventional CT, 7 cases were diagnosed as negative invasion on CT with gas distension technique and 5 cases of these were confirmed by surgery. 4. Among 11 cases with indistinguishable border between stomach and pancreas on conventional CT, 3 cases were diagnosed as negative invasion on CT with gas distension technique, all of which were confirmed by surgery. 5. There was no significant difference between conventional CT and CT with gas distension technique of the stomach to diagnose invasion into transverse colon, transverse colon, transverse mesocolon, lymph node metastasis, and various distant metastasis.

  3. Studies on the characteristics of the separated type heat pipe system with non-condensible gas for the use of the passive decay heat removal in reactor systems

    International Nuclear Information System (INIS)

    Hayashi, Takao; Iigaki, Kazuhiko; Ohashi, Kazutaka; Hayakawa, Hitoshi; Yamada, Masao.

    1995-01-01

    This study is the fundamental research by experiments to aim at the development of the complete passive decay heat removal system on the modular reactor systems by the form of the separated type of heat pipe system utilizing the features of both the big latent heat for vaporization from water to steam and easy transportation characteristics. Special intention in our study on the fundamental experiments is to look for the effects in such a separated type of heat pipe system to introduce non-condensible gas such as nitrogen gas together with the working fluid of water. Many interesting findings have been obtained so far on the experiments for the variable conductance heat pipe characteristics from viewpoint of the actual application on the aim said above. This study has been carried out by the joint study between Tokai University and Fuji Electric Co., Ltd. and this paper is made up from the several papers presented so far at both the national and international symposiums under the name of joint study of the both bodies. (author)

  4. Gas phase spectroscopic study of unstable molecules using FTIR technique

    International Nuclear Information System (INIS)

    Allaf, A.W.; Alibrahim, M.; Kassem, M.

    1998-01-01

    A new route has been developed, leading to the production of phosphorus (III) oxycyanide, OPCN and phosphorus (III) oxycyanate, OPOCN by an on-line process using phosphoryl chloride, POCL 3 as a starting material passed over heated silver at 870 Centigrade and then reacted with AgCN and KOCN heated at 270 Centigrade and 590 Centigrade to produce OPCN and OPOCN respectively. The gas phase fourier transform infrared spectra reported for the first time show the two characterized bonds of OPCN and OPOCN at 2165 cm -1 and 2130 cm -1 , assigned to the C≡N stretching fundamentals of OPCN and OPOCN respectively. (Author)

  5. Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

    Directory of Open Access Journals (Sweden)

    Xiao-Liang Wang

    2014-01-01

    Full Text Available We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the effectiveness of the stability criterion.

  6. Gas separation techniques with liquid Ar for production of 11C ions

    International Nuclear Information System (INIS)

    Hojo, Satoru; Honma, Toshihiro; Kanazawa, Mitsutaka; Muramatsu, Masayuki; Sakamoto, Yukio; Sugiura, Akinori; Suzuki, Naokata; Noda, Koji

    2009-01-01

    Heavy-ion cancer therapy with 12 C-beam has been carried out at HIMAC (Heavy Ion Medical Accelerator in Chiba) in NIRS (National Institute of Radiological Sciences) since 1994. One of the feasibility study in HIMAC is to use a positron emitter beam such as 11 C-beam for the cancer therapy. A nuclear reaction, 14 N (p,α) 11 C will be applied in the present study; it can be expected to obtain a considerably large number of 11 C-particles by utilizing the commonly used short-lives RI production techniques for PET (Positron Emission Tomography). The amount of 11 C gas is limited in this technique. The 11 CO 2 gas was produced from N 2 gas that is irradiated high-energy proton beam. Therefore, CO 2 gas separation from N 2 gas is very important. The gas-separation techniques with cryogenic system utilizing a liquid Ar were tested by dummy gas (N 2 + 12 CO 2 ). Details of the gas-separation techniques and measurement of CO 2 partial pressure are discussed. (author)

  7. Optimal sensor locations for the backward Lagrangian stochastic technique in measuring lagoon gas emission

    Science.gov (United States)

    This study evaluated the impact of gas concentration and wind sensor locations on the accuracy of the backward Lagrangian stochastic inverse-dispersion technique (bLS) for measuring gas emission rates from a typical lagoon environment. Path-integrated concentrations (PICs) and 3-dimensional (3D) wi...

  8. Development of detection techniques for the Swedish noble gas sampler

    Energy Technology Data Exchange (ETDEWEB)

    Ringbom, A

    1998-11-01

    A short review on the radioactive properties of noble gas isotopes relevant for monitoring of nuclear activities is given, together with a brief discussion of the existing systems for detection of radioactive noble gases. A 4{pi} detection system to be used in the automatic version of the Swedish noble gas sampling device is described. Monte Carlo calculations of the total gamma and beta efficiency for different detector designs have been performed, together with estimates of the resulting minimum detectable concentration (MDC). The estimated MDC values for detection of the {sup 133g}Xe 81 keV and the {sup 135g}Xe 250 keV gamma lines are around 0.3 mBq/m{sup 3} in both cases. This is a factor of three lower than the detection limit required for a sampling station in the Comprehensive Nuclear-Test-Ban Treaty monitoring network. The possibility to modify the system to detect {sup 85}Kr is also discussed 27 refs, 13 figs, 3 tabs

  9. Oxidation and Condensation of Zinc Fume From Zn-CO2-CO-H2O Streams Relevant to Steelmaking Off-Gas Systems

    International Nuclear Information System (INIS)

    Bronson, Tyler Mark; Ma, Naiyang; Zhu, Liang Zhu; Sohn, Hong Yong

    2017-01-01

    Here the objective of this research was to study the condensation of zinc vapor to metallic zinc and zinc oxide solid under varying environments to investigate the feasibility of in-process separation of zinc from steelmaking off-gas dusts. Water vapor content, temperature, degree of cooling, gas composition, and initial zinc partial pressure were varied to simulate the possible conditions that can occur within steelmaking off-gas systems, limited to Zn-CO 2 -CO-H 2 O gas compositions. The temperature of deposition and the effect of rapidly quenching the gas were specifically studied. A homogeneous nucleation model for applicable experiments was applied to the analysis of the experimental data. It was determined that under the experimental conditions, oxidation of zinc vapor by H 2 O or CO 2 does not occur above 1108 K (835 °C) even for highly oxidizing streams (CO 2 /CO = 40/7). Rate expressions that correlate CO 2 and H 2 O oxidation rates to gas composition, partial pressure of water vapor, temperature, and zinc partial pressure were determined to be as follows: Rate ((mol)/(m 2 s)) = 406 exp ((−50.2kJ/mol)/(RT)) (pZnpCO 2 − PCO/K eq CO 2 ) ((mol)/(m 2 xs)) Rate (((mol)/(m 2 s))) = 32.9 exp (((−13.7kJ/mol)/(RT))) (pZnPH 2 O − PH 2 /K eq H 2 O) ((mol)/(m 2 xs)). It was proven that a rapid cooling rate (500 K/s) significantly increases the ratio of metallic zinc to zinc oxide as opposed to a slow cooling rate (250 K/s). SEM analysis found evidence of heterogeneous growth of ZnO as well as of homogeneous formation of metallic zinc. The homogeneous nucleation model fit well with experiments where only metallic zinc deposited. An expanded model with rates of oxidation by CO 2 and H 2 O as shown was combined with the homogenous nucleation model and then compared with experimental data. The calculated results based on the model gave a reasonable fit to the measured data. For the conditions used in this study, the rate equations for the oxidation of zinc by

  10. ACCENT-BIAFLUX workshop 2005, trace gas and aerosol flux measurement and techniques. Abstract book

    Energy Technology Data Exchange (ETDEWEB)

    Werner, A.; Soerensen, L.L. (eds.)

    2005-04-01

    The woorkshop trace gas and aerosol flux measurement techniques in the second meeting within the Biosphere Atmosphere Exchange of Pollutions (BIAFLUX) group in the EU-network project Atmospheric Composition Change (ACCENT). The goal of the workshop is to obtain an overview of techniques for measurements of gas and aerosol fluxes and to gather the knowledge of uncertainties in flux measurements and calculations. The workshop is funded by ACCENT. The abstract book presents abstracts of 21 oral presentations and 26 poster presentations. (LN)

  11. Comparison of protein fermentation characteristics in rumen fluid determined with the gas production technique and the nylon bag technique

    NARCIS (Netherlands)

    Cone, J.W.; Rodrigues, M.A.M.; Guedes, C.M.; Blok, M.C.

    2009-01-01

    In this study, a modified version of the gas production technique was used to determine protein fermentation characteristics in rumen fluid of 19 feedstuffs. Performing the incubations in a N-free environment, and with an excess of rapidly fermentable carbohydrates, made N the limiting factor to

  12. Effects of gas composition in headspace and bicarbonate concentrations in media on gas and methane production, degradability, and rumen fermentation using in vitro gas production techniques.

    Science.gov (United States)

    Patra, Amlan Kumar; Yu, Zhongtang

    2013-07-01

    Headspace gas composition and bicarbonate concentrations in media can affect methane production and other characteristics of rumen fermentation in in vitro gas production systems, but these 2 important factors have not been evaluated systematically. In this study, these 2 factors were investigated with respect to gas and methane production, in vitro digestibility of feed substrate, and volatile fatty acid (VFA) profile using in vitro gas production techniques. Three headspace gas compositions (N2+ CO2+ H2 in the ratio of 90:5:5, CO2, and N2) with 2 substrate types (alfalfa hay only, and alfalfa hay and a concentrate mixture in a 50:50 ratio) in a 3×2 factorial design (experiment 1) and 3 headspace compositions (N2, N2 + CO2 in a 50:50 ratio, and CO2) with 3 bicarbonate concentrations (80, 100, and 120 mM) in a 3×3 factorial design (experiment 2) were evaluated. In experiment 1, total gas production (TGP) and net gas production (NGP) was the lowest for CO2, followed by N2, and then the gas mixture. Methane concentration in headspace gas after fermentation was greater for CO2 than for N2 and the gas mixture, whereas total methane production (TMP) and net methane production (NMP) were the greatest for CO2, followed by the gas mixture, and then N2. Headspace composition did not affect in vitro digestibility or the VFA profile, except molar percentages of propionate, which were greater for CO2 and N2 than for the gas mixture. Methane concentration in headspace gas, TGP, and NGP were affected by the interaction of headspace gas composition and substrate type. In experiment 2, increasing concentrations of CO2 in the headspace decreased TGP and NGP quadratically, but increased the concentrations of methane, NMP, and in vitro fiber digestibility linearly, and TMP quadratically. Fiber digestibility, TGP, and NGP increased linearly with increasing bicarbonate concentrations in the medium. Concentrations of methane and NMP were unaffected by bicarbonate concentration, but

  13. The Effects of a Macromolecular Charring Agent with Gas Phase and Condense Phase Synergistic Flame Retardant Capability on the Properties of PP/IFR Composites

    Science.gov (United States)

    Chen, Hongda; Wang, Jihui; Ding, Anxin; Han, Xia; Sun, Ziheng

    2018-01-01

    In order to improve the efficiency of intumescent flame retardants (IFRs), a novel macromolecular charring agent named poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine) (PETAT) with gas phase and condense phase synergistic flame-retardant capability was synthesized and subsequently dispersed into polypropylene (PP) in combination with ammonium polyphosphate (APP) via a melt blending method. The chemical structure of PETAT was investigated by Fourier transform infrared spectroscopy (FTIR), and 1H nuclear magnetic resonance (NMR) spectroscopy. Thermal properties of the PETAT and IFR systems were tested by thermogravimetric-derivative thermogravimetric analysis (TGA-DTG) and thermogravimetry–Fourier transform infrared spectroscopy (TG-FTIR). The mechanical properties, thermal stability, flame-retardant properties, water resistance, and structures of char residue in flame-retardant composites were characterized using tensile and flexural strength property tests, TGA, limiting oxygen index (LOI) values before and after soaking, underwritten laboratory-94 (UL-94) vertical burning test, cone calorimetric test (CCT), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDXS), and FTIR. The results indicated that PETAT was successfully synthesized, and when the ratio of APP to PETAT was 2:1 with 25 wt % loading, the novel IFR system could reduce the deterioration of tensile strength and enhance the flexural strength of composites. Meanwhile, the flame-retardant composite was able to pass the UL-94 V-0 rating with an LOI value of 30.3%, and the peak of heat release rate (PHRR), total heat release (THR), and material fire hazard values were considerably decreased compared with others. In addition, composites also exhibited excellent water resistance properties compared with traditional IFR composites. SEM-EDXS and FTIR analyses of the char residues, as well as TG-FTIR analyses of IFR were used to investigate the flame

  14. The Effects of a Macromolecular Charring Agent with Gas Phase and Condense Phase Synergistic Flame Retardant Capability on the Properties of PP/IFR Composites

    Directory of Open Access Journals (Sweden)

    Hongda Chen

    2018-01-01

    Full Text Available In order to improve the efficiency of intumescent flame retardants (IFRs, a novel macromolecular charring agent named poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine (PETAT with gas phase and condense phase synergistic flame-retardant capability was synthesized and subsequently dispersed into polypropylene (PP in combination with ammonium polyphosphate (APP via a melt blending method. The chemical structure of PETAT was investigated by Fourier transform infrared spectroscopy (FTIR, and 1H nuclear magnetic resonance (NMR spectroscopy. Thermal properties of the PETAT and IFR systems were tested by thermogravimetric-derivative thermogravimetric analysis (TGA-DTG and thermogravimetry–Fourier transform infrared spectroscopy (TG-FTIR. The mechanical properties, thermal stability, flame-retardant properties, water resistance, and structures of char residue in flame-retardant composites were characterized using tensile and flexural strength property tests, TGA, limiting oxygen index (LOI values before and after soaking, underwritten laboratory-94 (UL-94 vertical burning test, cone calorimetric test (CCT, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDXS, and FTIR. The results indicated that PETAT was successfully synthesized, and when the ratio of APP to PETAT was 2:1 with 25 wt % loading, the novel IFR system could reduce the deterioration of tensile strength and enhance the flexural strength of composites. Meanwhile, the flame-retardant composite was able to pass the UL-94 V-0 rating with an LOI value of 30.3%, and the peak of heat release rate (PHRR, total heat release (THR, and material fire hazard values were considerably decreased compared with others. In addition, composites also exhibited excellent water resistance properties compared with traditional IFR composites. SEM-EDXS and FTIR analyses of the char residues, as well as TG-FTIR analyses of IFR were used to investigate the flame

  15. The Effects of a Macromolecular Charring Agent with Gas Phase and Condense Phase Synergistic Flame Retardant Capability on the Properties of PP/IFR Composites.

    Science.gov (United States)

    Chen, Hongda; Wang, Jihui; Ni, Aiqing; Ding, Anxin; Han, Xia; Sun, Ziheng

    2018-01-11

    In order to improve the efficiency of intumescent flame retardants (IFRs), a novel macromolecular charring agent named poly(ethanediamine-1,3,5-triazine-p-4-amino-2,2,6,6-tetramethylpiperidine) (PETAT) with gas phase and condense phase synergistic flame-retardant capability was synthesized and subsequently dispersed into polypropylene (PP) in combination with ammonium polyphosphate (APP) via a melt blending method. The chemical structure of PETAT was investigated by Fourier transform infrared spectroscopy (FTIR), and ¹H nuclear magnetic resonance (NMR) spectroscopy. Thermal properties of the PETAT and IFR systems were tested by thermogravimetric-derivative thermogravimetric analysis (TGA-DTG) and thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR). The mechanical properties, thermal stability, flame-retardant properties, water resistance, and structures of char residue in flame-retardant composites were characterized using tensile and flexural strength property tests, TGA, limiting oxygen index (LOI) values before and after soaking, underwritten laboratory-94 (UL-94) vertical burning test, cone calorimetric test (CCT), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDXS), and FTIR. The results indicated that PETAT was successfully synthesized, and when the ratio of APP to PETAT was 2:1 with 25 wt % loading, the novel IFR system could reduce the deterioration of tensile strength and enhance the flexural strength of composites. Meanwhile, the flame-retardant composite was able to pass the UL-94 V-0 rating with an LOI value of 30.3%, and the peak of heat release rate (PHRR), total heat release (THR), and material fire hazard values were considerably decreased compared with others. In addition, composites also exhibited excellent water resistance properties compared with traditional IFR composites. SEM-EDXS and FTIR analyses of the char residues, as well as TG-FTIR analyses of IFR were used to investigate the flame

  16. Stopped-flow technique for transit time measurement in a gas jet

    International Nuclear Information System (INIS)

    Rengan, K.; Lin, J.; Lim, T.; Meyer, R.A.; Harrell, J.

    1985-01-01

    A 'stopped-flow' technique for the measurement of transit time of reaction products in a gas jet is described. The method involved establishing the gas flow through the jet system when the reactor is operating steadily and allowing the pressure to reach equilibrium values. The gas flow is stopped by means of electrically operated valves. The transit-time measurement is achieved by opening the valves and initiating the multiscanning of total activity simultaneously. The value obtained agrees well with the transit time measured by pulsing the reactor. The 'stopped-flow' technique allows on-line measurement of transit time in any gas jet system where the physical transportation time is the major component of the transit time. This technique is especially useful for systems installed in reactors which do not have pulsing capability. (orig.)

  17. Condensed matter physics

    CERN Document Server

    Isihara, A

    2007-01-01

    More than a graduate text and advanced research guide on condensed matter physics, this volume is useful to plasma physicists and polymer chemists, and their students. It emphasizes applications of statistical mechanics to a variety of systems in condensed matter physics rather than theoretical derivations of the principles of statistical mechanics and techniques. Isihara addresses a dozen different subjects in separate chapters, each designed to be directly accessible and used independently of previous chapters. Topics include simple liquids, electron systems and correlations, two-dimensional

  18. Condensate growth in trapped Bose gates

    NARCIS (Netherlands)

    Bijlsma, M.J.; Zaremba, E.; Stoof, H.T.C.

    2000-01-01

    We study the dynamics of condensate fromation in an inhomogeneous trapped Bose gas with a positive interatomic scattering length. We take into account both the nonequilibrium kinetics of the thermal cloud and the Hartree-Fock mean-field efects in the condensed and the noncondensed parts of the gas.

  19. Condensate growth in trapped Bose gases

    NARCIS (Netherlands)

    Bijlsma, M.J.; Zaremba, E.; Stoof, H.T.C.

    2000-01-01

    We study the dynamics of condensate formation in an inhomogeneous trapped Bose gas with a positive interatomic scattering length. We take into account both the nonequilibrium kinetics of the thermal cloud and the Hartree-Fock mean-field effects in the condensed and the noncondensed parts of the gas.

  20. The development of an electrochemical technique for in situ calibrating of combustible gas detectors

    Science.gov (United States)

    Shumar, J. W.; Lantz, J. B.; Schubert, F. H.

    1976-01-01

    A program to determine the feasibility of performing in situ calibration of combustible gas detectors was successfully completed. Several possible techniques for performing the in situ calibration were proposed. The approach that showed the most promise involved the use of a miniature water vapor electrolysis cell for the generation of hydrogen within the flame arrestor of a combustible gas detector to be used for the purpose of calibrating the combustible gas detectors. A preliminary breadboard of the in situ calibration hardware was designed, fabricated and assembled. The breadboard equipment consisted of a commercially available combustible gas detector, modified to incorporate a water vapor electrolysis cell, and the instrumentation required for controlling the water vapor electrolysis and controlling and calibrating the combustible gas detector. The results showed that operation of the water vapor electrolysis at a given current density for a specific time period resulted in the attainment of a hydrogen concentration plateau within the flame arrestor of the combustible gas detector.

  1. Gas hydrate phase equilibria measurement techniques and phase rule considerations

    International Nuclear Information System (INIS)

    Beltran, Juan G.; Bruusgaard, Hallvard; Servio, Phillip

    2012-01-01

    Highlights: → Inconsistencies found in hydrate literature. → Clarification to the number of variables needed to satisfy and justify equilibrium data. → Application of phase rule to mixed hydrate systems. → Thermodynamically consistent format to present data. - Abstract: A brief review of the Gibbs phase rule for non-reacting systems and its correct application to clathrate hydrates is presented. Clarification is provided for a common mistake found in hydrate phase-equilibria literature, whereby initial compositions are used as intensive variables to satisfy the Gibbs phase rule instead of the equilibrium values. The system of (methane + carbon dioxide + water) under (hydrate + liquid + vapor) equilibrium is used as a case study to illustrate key points and suggestions to improve experimental techniques are proposed.

  2. A simple nondestructive technique for monitoring the bond gas in sealed fast reactor nuclear fuel pins

    Energy Technology Data Exchange (ETDEWEB)

    Shriwastwa, B B; Mehrotra, R S; Ghosh, J K [Bhabha Atomic Research Centre, Bombay (India). Radiometallurgy Div.

    1994-12-31

    A simple nondestructive testing technique has been developed to identify bond gas inside a welded fuel pin. The technique is based on the accurate surface temperature measurement of fuel pins heated in a constant temperature water bath. This technique can be applied in Fast Breeder Test Reactor (FBTR) fuel pin production line due to simplicity of the set up, simple operation and quick response time. An attempt was made to develop a non destructive test method for monitoring the bond gas composition. Preliminary development work carried out in this connection, the test method adopted and the test results are presented. 1 ref., 5 figs., 1 tab.

  3. Multiple inert gas elimination technique by micropore membrane inlet mass spectrometry--a comparison with reference gas chromatography.

    Science.gov (United States)

    Kretzschmar, Moritz; Schilling, Thomas; Vogt, Andreas; Rothen, Hans Ulrich; Borges, João Batista; Hachenberg, Thomas; Larsson, Anders; Baumgardner, James E; Hedenstierna, Göran

    2013-10-15

    The mismatching of alveolar ventilation and perfusion (VA/Q) is the major determinant of impaired gas exchange. The gold standard for measuring VA/Q distributions is based on measurements of the elimination and retention of infused inert gases. Conventional multiple inert gas elimination technique (MIGET) uses gas chromatography (GC) to measure the inert gas partial pressures, which requires tonometry of blood samples with a gas that can then be injected into the chromatograph. The method is laborious and requires meticulous care. A new technique based on micropore membrane inlet mass spectrometry (MMIMS) facilitates the handling of blood and gas samples and provides nearly real-time analysis. In this study we compared MIGET by GC and MMIMS in 10 piglets: 1) 3 with healthy lungs; 2) 4 with oleic acid injury; and 3) 3 with isolated left lower lobe ventilation. The different protocols ensured a large range of normal and abnormal VA/Q distributions. Eight inert gases (SF6, krypton, ethane, cyclopropane, desflurane, enflurane, diethyl ether, and acetone) were infused; six of these gases were measured with MMIMS, and six were measured with GC. We found close agreement of retention and excretion of the gases and the constructed VA/Q distributions between GC and MMIMS, and predicted PaO2 from both methods compared well with measured PaO2. VA/Q by GC produced more widely dispersed modes than MMIMS, explained in part by differences in the algorithms used to calculate VA/Q distributions. In conclusion, MMIMS enables faster measurement of VA/Q, is less demanding than GC, and produces comparable results.

  4. Current Techniques of Growing Algae Using Flue Gas from Exhaust Gas Industry: a Review.

    Science.gov (United States)

    Huang, Guanhua; Chen, Feng; Kuang, Yali; He, Huan; Qin, An

    2016-03-01

    The soaring increase of flue gas emission had caused global warming, environmental pollution as well as climate change. Widespread concern on reduction of flue gas released from industrial plants had considered the microalgae as excellent biological materials for recycling the carbon dioxide directly emitted from exhaust industries. Microalgae also have the potential to be the valuable feedback for renewable energy production due to their high growth rate and abilities to sequester inorganic carbon through photosynthetic process. In this review article, we will illustrate important relative mechanisms in the metabolic processes of biofixation by microalgae and their recent experimental researches and advances of sequestration of carbon dioxide by microalgae on actual industrial and stimulate flue gases, novel photobioreactor cultivation systems as well as the perspectives and limitations of microalgal cultivation in further development.

  5. Measurement of water absorption capacity in wheat flour by a headspace gas chromatographic technique.

    Science.gov (United States)

    Xie, Wei-Qi; Yu, Kong-Xian; Gong, Yi-Xian

    2018-04-17

    The purpose of this work is to introduce a new method for quantitatively analyzing water absorption capacity in wheat flour by a headspace gas chromatographic technique. This headspace gas chromatographic technique was based on measuring the water vapor released from a series of wheat flour samples with different contents of water addition. According to the different trends between the vapor and wheat flour phase before and after the water absorption capacity in wheat flour, a turning point (corresponding to water absorption capacity in wheat flour) can be obtained by fitting the data of the water gas chromatography peak area from different wheat flour samples. The data showed that the phase equilibrium in the vial can be achieved in 25 min at desired temperature (35°C). The relative standard deviation of the reaction headspace gas chromatographic technique in water absorption capacity determination was within 3.48%, the relative differences has been determined by comparing the water absorption capacity obtained from this new analytical technique with the data from the reference technique (i.e., the filtration method), which are less than 8.92%. The new headspace gas chromatographic method is automated, accurate and be a reliable tool for quantifying water absorption capacity in wheat flour in both laboratory research and mill applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Leak testing of bubble-tight dampers using tracer gas techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lagus, P.L. [Lagus Applied Technology, Inc., San Diego, CA (United States); DuBois, L.J. [Commonwealth Edison, Zion, IL (United States); Fleming, K.M. [NCS Corporation, Columbus, OH (United States)] [and others

    1995-02-01

    Recently tracer gas techniques have been applied to the problem of measuring the leakage across an installed bubble-tight damper. A significant advantage of using a tracer gas technique is that quantitative leakage data are obtained under actual operating differential pressure conditions. Another advantage is that leakage data can be obtained using relatively simple test setups that utilize inexpensive materials without the need to tear ducts apart, fabricate expensive blank-off plates, and install test connections. Also, a tracer gas technique can be used to provide an accurate field evaluation of the performance of installed bubble-tight dampers on a periodic basis. Actual leakage flowrates were obtained at Zion Generating Station on four installed bubble-tight dampers using a tracer gas technique. Measured leakage rates ranged from 0.01 CFM to 21 CFM. After adjustment and subsequent retesting, the 21 CFM damper leakage was reduced to a leakage of 3.8 CFM. In light of the current regulatory climate and the interest in Control Room Habitability issues, imprecise estimates of critical air boundary leakage rates--such as through bubble-tight dampers--are not acceptable. These imprecise estimates can skew radioactive dose assessments as well as chemical contaminant exposure calculations. Using a tracer gas technique, the actual leakage rate can be determined. This knowledge eliminates a significant source of uncertainty in both radioactive dose and/or chemical exposure assessments.

  7. Polariton condensates

    International Nuclear Information System (INIS)

    Snoke, David; Littlewood, Peter

    2010-01-01

    Most students of physics know about the special properties of Bose-Einstein condensates (BECs) as demonstrated in the two best-known examples: superfluid helium-4, first reported in 1938, and condensates of trapped atomic gases, first observed in 1995. (See the article by Wolfgang Ketterle in PHYSICS TODAY, December 1999, page 30.) Many also know that superfluid 3 He and superconducting metals contain BECs of fermion pairs. An underlying principle of all those condensed-matter systems, known as quantum fluids, is that an even number of fermions with half-integer spin can be combined to make a composite boson with integer spin. Such composite bosons, like all bosons, have the property that below some critical temperature--roughly the temperature at which the thermal de Broglie wavelength becomes comparable to the distance between the bosons--the total free energy is minimized by having a macroscopic number of bosons enter a single quantum state and form a macroscopic, coherent matter wave. Remarkably, the effect of interparticle repulsion is to lead to quantum mechanical exchange interactions that make that state robust, since the exchange interactions add coherently.

  8. 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.)

  9. Improving the gas productivity of the alkaline electrolyzer through the circulation technique

    Directory of Open Access Journals (Sweden)

    Kitipong Tangphant

    2014-03-01

    Full Text Available This research aims to study and improve the efficiency of a KOH electrolyzer through the gas productivity of the electrolyzer with different the circulation technique. In this work, the conceptual design of an electrolyzer falls into 2 categories; without pumping and with pumping. Direct current electricity at 5 different levels of 10, 15, 20, 25 and 30 A are charged into the system and the gas flow rate generated from the electrolyzer is subsequently monitored. The results show that at 30 A the gas generated from the circulation with pumping and the circulation without pumping are 2.31 litre/min and 1.76 litre/min, respectively. It is also found that the energy consumed by both techniques is the same; however, the circulation with pumping design shows the better gas productivity than that of the circulation without pumping design.

  10. The gas cushion technique as a handling means for the remote removal of tokamak segments

    International Nuclear Information System (INIS)

    Removille, J.; Stephano, R.

    1983-01-01

    The gas cushion technique has been studied as offering a compact, flexible and safe way of handling massive objects. The evolution of the gas-cushion handling philosophy is discussed and examples presented related to the displacements of different loads in the torus and in the reactor hall. A short technical comparison with the C-frame handling concept is made in the conclusion. (author)

  11. Evaluation of serpentine ore as a nuclear shielding material using gas chromatographic techniques

    International Nuclear Information System (INIS)

    Singh, B.N.; Unnikrishnan, E.K.; Kumar, Sangita D.

    2007-01-01

    Serpentine ore mixed with cement has been recognized as a candidate shielding material for use in nuclear reactors because of its many desirable properties. Therefore the assessment of serpentine ore for release of volatile gases during exposure to elevated temperatures, irradiation and changes in chemical composition, is essential. The present paper deals with the studies on the serpentine ores using gas chromatography and combustion gas chromatographic techniques. (author)

  12. Hyphenated techniques in multidimensional gas chromatography for analysis of wine aroma and related odorants

    OpenAIRE

    Chin, Sung Tong

    2017-01-01

    The advent of analytical multidimensional gas chromatography (MDGC) techniques, with recent development in comprehensive two-dimensional gas chromatography (GC×GC) as well as microfluidic technology in conventional heart-cut MDGC, has achieved excellent separation efficiency for advanced characterization of complex volatile and semi-volatile samples, which is unlikely to be accomplished by single dimensional chromatography. This dissertation work has highlighted the potential opportunities fo...

  13. Measurement of liquid-liquid equilibria for condensate + glycol and condensate + glycol + water systems

    DEFF Research Database (Denmark)

    Riaz, Muhammad; Kontogeorgis, Georgios; Stenby, Erling Halfdan

    2011-01-01

    ,2-ethanediol (MEG) + condensate and MEG + water + condensate systems at temperatures from (275 to 323) K at atmospheric pressure. The condensate used in this work is a stabilized natural gas condensate from an offshore field in the North Sea. Compositional analysis of the natural gas condensate was carried out...... by gas chromatography, and detailed separation of individual condensate's components has been carried out. Approximately 85 peaks eluting before nonane were identified by their retention time. Peak areas were converted to mass fraction using 1-heptene as an internal standard. The components were divided...... into boiling range groups from hexane to nonane. Paraffinic (P), naphthenic (N), and aromatic (A) distributions were obtained for the boiling point fractions up to nonane. The average molar mass and the overall density of the condensate were measured experimentally. For the mutual solubility of MEG...

  14. Calculational techniques for estimating population doses from radioactivity in natural gas from nuclearly stimulated wells

    International Nuclear Information System (INIS)

    Barton, C.J.; Moore, R.E.; Rohwer, P.S.; Kaye, S.V.

    1975-01-01

    Techniques for estimating radiation doses from exposure to combustion products of natural gas obtained from wells created by use of nuclear explosives were first developed in the Gasbuggy Project. These techniques were refined and extended by development of a number of computer codes in studies related to the Rulison Project, the second in the series of joint government-industry efforts to demonstrate the feasibility of increasing natural gas production from low-permeability rock formations by use of nuclear explosives. These techniques are described and dose estimates that illustrate their use are given. These dose estimation studies have been primarily theoretical, but we have tried to make our hypothetical exposure conditions correspond as closely as possible with conditions that could exist if nuclearly stimulated natural gas is used commercially. (author)

  15. Some new techniques in tritium gas handling as applied to metal hydride synthesis

    International Nuclear Information System (INIS)

    Nasise, J.E.

    1988-01-01

    A state-of-the-art tritium Hydriding Synthesis System (HSS) was designed and built to replace the existing system within the Tritium Salt Facility (TSF) at the Los Alamos National Laboratory. This new hydriding system utilizes unique fast-cycling 7.9 mole uranium beds (47.5g of T at 100% loading) and novel gas circulating hydriding furnaces. Tritium system components discussed include fast-cycling uranium beds, circulating gas hydriding furnaces, valves, storage volumes, manifolds, gas transfer pumps, and graphic display and control consoles. Many of the tritium handling and processing techniques incorporated into this system are directly applicable to today's fusion fuel loops. 12 refs., 7 figs

  16. Application of Arma Technique For Operation Stability of RSG-Gas

    International Nuclear Information System (INIS)

    Djudjuratisbela, Udju

    2000-01-01

    Application Of Arma Technique For Operation Stability Of RSG-Gas. Application of Fast Fourier Transport (FFT) method in the noise experiments data had been conducted to reactor kinetic parameter determination of RSG-Gas. Reactor stability that has closed relation to operation safety has not been measured yet. Noise analysis method and ARMA (Auto Regressive Moving Average) technique that has capability to identify mathematical model of the noise experimental data can be used for determination of kinetic/dynamic characteristic equation and its roots. From the roots of reactor characteristic equation, magnitude of natural frequency (fn), damping ratio (xi), damping frequency (fd), decay ratio (delta) and then reactor stability can be calculated

  17. Impact of Detoxification Techniques on Pulmonary Gas Exchange Function in Patients with Generalized Peritonitis

    Directory of Open Access Journals (Sweden)

    R. A. Mlinnik

    2012-01-01

    Full Text Available Objective: to analyze the impact of different detoxification techniques on pulmonary gas exchange function in patients with generalized peritonitis complicated by multiple organ failure. Subjects and methods. One hundred and thirty patients with generalized peritonitis were examined. According to the used detoxification techniques, the patients were divided into 5 groups. All the patients underwent a comprehensive examination, the key element of which was the evaluation of gas exchange parameters. Results. Membrane plasmapheresis and plasmapheresis with sodium hypochlorite infusion to the plasma filter in patients with peritonitis are shown to improve pulmonary blood oxygenation.

  18. Two dimensional numerical simulation of gas discharges: comparison between particle-in-cell and FCT techniques

    Energy Technology Data Exchange (ETDEWEB)

    Soria-Hoyo, C; Castellanos, A [Departamento de Electronica y Electromagnetismo, Facultad de Fisica, Universidad de Sevilla, Avda. Reina Mercedes s/n, 41012 Sevilla (Spain); Pontiga, F [Departamento de Fisica Aplicada II, EUAT, Universidad de Sevilla, Avda. Reina Mercedes s/n, 41012 Sevilla (Spain)], E-mail: cshoyo@us.es

    2008-10-21

    Two different numerical techniques have been applied to the numerical integration of equations modelling gas discharges: a finite-difference flux corrected transport (FD-FCT) technique and a particle-in-cell (PIC) technique. The PIC technique here implemented has been specifically designed for the simulation of 2D electrical discharges using cylindrical coordinates. The development and propagation of a streamer between two parallel electrodes has been used as a convenient test to compare the performance of both techniques. In particular, the phase velocity of the cathode directed streamer has been used to check the internal consistency of the numerical simulations. The results obtained from the two techniques are in reasonable agreement with each other, and both techniques have proved their ability to follow the high gradients of charge density and electric field present in this type of problems. Moreover, the streamer velocities predicted by the simulation are in accordance with the typical experimental values.

  19. Two dimensional numerical simulation of gas discharges: comparison between particle-in-cell and FCT techniques

    International Nuclear Information System (INIS)

    Soria-Hoyo, C; Castellanos, A; Pontiga, F

    2008-01-01

    Two different numerical techniques have been applied to the numerical integration of equations modelling gas discharges: a finite-difference flux corrected transport (FD-FCT) technique and a particle-in-cell (PIC) technique. The PIC technique here implemented has been specifically designed for the simulation of 2D electrical discharges using cylindrical coordinates. The development and propagation of a streamer between two parallel electrodes has been used as a convenient test to compare the performance of both techniques. In particular, the phase velocity of the cathode directed streamer has been used to check the internal consistency of the numerical simulations. The results obtained from the two techniques are in reasonable agreement with each other, and both techniques have proved their ability to follow the high gradients of charge density and electric field present in this type of problems. Moreover, the streamer velocities predicted by the simulation are in accordance with the typical experimental values.

  20. Modeling of gas condensates properties using continuous distribution functions for the characterization of the plus fraction; Modelisation des proprietes thermodynamiques des gaz a condensat par representation de la fraction lourde a l`aide de fonctions de distribution

    Energy Technology Data Exchange (ETDEWEB)

    Sportisse, M.

    1996-12-20

    The modeling of thermodynamic behaviour for gas condensates is not yet satisfactory and it involves an adjustment of thermodynamic models. We propose here a fitting based on the characterization of the plus fraction using three continuous distribution functions associated to the following families: n-alkanes, n-alkylbenzenes and poly-aromatics. No continuous thermodynamic model is used and PVT calculations are made with the Peng-Robinson equation of state. For poly-aromatics, a simple correlation of {l_brace} T{sub c}, P{sub c}, {omega} {r_brace} is given. The parameters of the distributions are fitted in order to improve the accuracy of the liquid deposit curve calculation. A continuous minimization by simulated annealing has been used to avoid local minima. Good results on fitting PVT properties have been obtained with more than twenty gas condensates from different areas. Moreover, the prediction of tank liquid and heavy-plus fraction densities are given with an average deviation of 1.2 % and 3.6 %. Tests on temperature extrapolation show that our modeling yields a good representation of pressure and temperature influence on gas condensates behaviour. (author) 89 refs.

  1. Continuous condensation in nanogrooves

    Science.gov (United States)

    Malijevský, Alexandr

    2018-05-01

    We consider condensation in a capillary groove of width L and depth D , formed by walls that are completely wet (contact angle θ =0 ), which is in a contact with a gas reservoir of the chemical potential μ . On a mesoscopic level, the condensation process can be described in terms of the midpoint height ℓ of a meniscus formed at the liquid-gas interface. For macroscopically deep grooves (D →∞ ), and in the presence of long-range (dispersion) forces, the condensation corresponds to a second-order phase transition, such that ℓ ˜(μcc-μ ) -1 /4 as μ →μcc - where μc c is the chemical potential pertinent to capillary condensation in a slit pore of width L . For finite values of D , the transition becomes rounded and the groove becomes filled with liquid at a chemical potential higher than μc c with a difference of the order of D-3. For sufficiently deep grooves, the meniscus growth initially follows the power law ℓ ˜(μcc-μ ) -1 /4 , but this behavior eventually crosses over to ℓ ˜D -(μ-μc c) -1 /3 above μc c, with a gap between the two regimes shown to be δ ¯μ ˜D-3 . Right at μ =μc c , when the groove is only partially filled with liquid, the height of the meniscus scales as ℓ*˜(D3L) 1 /4 . Moreover, the chemical potential (or pressure) at which the groove is half-filled with liquid exhibits a nonmonotonic dependence on D with a maximum at D ≈3 L /2 and coincides with μc c when L ≈D . Finally, we show that condensation in finite grooves can be mapped on the condensation in capillary slits formed by two asymmetric (competing) walls a distance D apart with potential strengths depending on L . All these predictions, based on mesoscopic arguments, are confirmed by fully microscopic Rosenfeld's density functional theory with a reasonable agreement down to surprisingly small values of both L and D .

  2. Visual Investigation of Retrograde Phenomena and Gas Condensate Flow in Porous Media Étude visuelle des phénomènes rétrogrades et de l'écoulement des gaz de condensat en milieux poreux

    Directory of Open Access Journals (Sweden)

    Danesh A.

    2006-11-01

    Full Text Available The mechanism of retrograde condensation and the flow of gas-condensate in horizontal porous media under simulated reservoir conditions were visually studied. Two-dimensional glass micromodels with homogeneous pore structures, as well as heterogeneous patterns, reproduced from real rock micrographs were employed in this study. Depletion tests were carried out using synthetic multicomponent hydrocarbon gas mixtures and also a North Sea gas condensate. The multiphase flow behaviour of the tested systems, as observed and recorded on video, is presented here along with the measured data. In water-wet pores, condensate was observed to be formed as a continuous thin film on connate water, which was the preferred site for condensation. Pressure reduction below the system cricondenbar resulted in the growth of the condensate almost exclusively on water rings at pore throats and dead end pores. The condensate was observed to flow through thin films even at low saturations, with little contribution to the condensate recovery. The rate of pressure depletion influenced the gas flow shear and was found to strongly affect the condensate propagation. Local instabilities could promote significant condensate movement in pore sections which would only be retarded further downstream by capillary effects diminishing the condensate recovery. Relative permeability-saturation relation-ships for gas-condensate flow should not be expected to take the same form as the oil-gas relative permeability for solution gas or external gas drive. Le mécanisme de la condensation rétrograde et l'écoulement des gaz de condensat en milieu poreux horizontal dans une simulation des conditions naturelles ont fait l'objet d'études visuelles. Des micromodèles en verre bi-dimensionnels à structure poreuse homogène, et des éléments hétérogènes reproduisant des micrographies de roches réelles, ont été utilisés pour cette étude. Des essais d'épuisement ont été effectu

  3. Gas analysis within remote porous targets using LIDAR multi-scatter techniques

    Science.gov (United States)

    Guan, Z. G.; Lewander, M.; Grönlund, R.; Lundberg, H.; Svanberg, S.

    2008-11-01

    Light detection and ranging (LIDAR) experiments are normally pursued for range resolved atmospheric gas measurements or for analysis of solid target surfaces using fluorescence of laser-induced breakdown spectroscopy. In contrast, we now demonstrate the monitoring of free gas enclosed in pores of materials, subject to impinging laser radiation, employing the photons emerging back to the surface laterally of the injection point after penetrating the medium in heavy multiple scattering processes. The directly reflected light is blocked by a beam stop. The technique presented is a remote version of the newly introduced gas in scattering media absorption spectroscopy (GASMAS) technique, which so far was pursued with the injection optics and the detector in close contact with the sample. Feasibility measurements of LIDAR-GASMAS on oxygen in polystyrene foam were performed at a distance of 6 m. Multiple-scattering induced delays of the order of 50 ns, which corresponds to 15 m optical path length, were observed. First extensions to a range of 60 m are discussed. Remote observation of gas composition anomalies in snow using differential absorption LIDAR (DIAL) may find application in avalanche victim localization or for leak detection in snow-covered natural gas pipelines. Further, the techniques may be even more useful for short-range, non-intrusive GASMAS measurements, e.g., on packed food products.

  4. Morphological comparison of PVA scaffolds obtained by gas foaming and microfluidic foaming techniques.

    Science.gov (United States)

    Colosi, Cristina; Costantini, Marco; Barbetta, Andrea; Pecci, Raffaella; Bedini, Rossella; Dentini, Mariella

    2013-01-08

    In this article, we have exploited a microfluidic foaming technique for the generation of highly monodisperse gas-in-liquid bubbles as a templating system for scaffolds characterized by an ordered and homogeneous porous texture. An aqueous poly(vinyl alcohol) (PVA) solution (containing a surfactant) and a gas (argon) are injected simultaneously at constant flow rates in a flow-focusing device (FFD), in which the gas thread breaks up to form monodisperse bubbles. Immediately after its formation, the foam is collected and frozen in liquid nitrogen, freeze-dried, and cross-linked with glutaraldehyde. In order to highlight the superior morphological quality of the obtained porous material, a comparison between this scaffold and another one, also constituted of PVA but obtained with a traditional gas foaming technique, was carried out. Such a comparison has been conducted by analyzing electron microscopy and X-ray microtomographic images of the two samples. It turned out that the microfluidic produced scaffold was characterized by much more uniform porous texture than the gas-foaming one as witnessed by narrower pore size, interconnection, and wall thickness distributions. On the other side, scarce pore interconnectivity, relatively low pore volume, and limited production rate represent, by now, the principal disadvantages of microfluidic foaming as scaffold fabrication method, emphasizing the kind of improvement that this technique needs to undergo.

  5. Investigations of astrophysically interesting nuclear reactions by the use of gas target techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, J W [Inst. fuer Strahlenphysik, Univ. Stuttgart, Stuttgart (Germany)

    1998-06-01

    A brief review of the common properties of windowless and recirculating gas targets is presented. As example the Stuttgart gas target facility Rhinoceros in the extended and in the supersonic jet mode with its properties and techniques is explained, also with respect to gas purification techniques. Furthermore several typical experiments from the field of nuclear astrophysics with characteristic results are described (D({alpha},{gamma}){sup 6}Li, {sup 15}N({alpha},{gamma}){sup 19}F, {sup 16}O(p,{gamma}){sup 17}F, {sup 16}O({alpha},{gamma}){sup 20}Ne, {sup 20}Ne({alpha},{gamma}){sup 24}Mg, {sup 21}Ne({alpha},n){sup 24}Mg, {sup 18}O({alpha},n){sup 21}Ne, {sup 17}O({alpha},n){sup 20}Ne). In several cases the experimental sensitivity could be raised by up to a factor of 10{sup 6}. (orig.)

  6. Mississippi exploration field trials using microbial, radiometrics, free soil gas, and other techniques

    Energy Technology Data Exchange (ETDEWEB)

    Moody, J.S.; Brown, L.R.; Thieling, S.C.

    1995-12-31

    The Mississippi Office of Geology has conducted field trials using the surface exploration techniques of geomicrobial, radiometrics, and free soil gas. The objective of these trials is to determine if Mississippi oil and gas fields have surface hydrocarbon expression resulting from vertical microseepage migration. Six fields have been surveyed ranging in depth from 3,330 ft to 18,500 ft. The fields differ in trapping styles and hydrocarbon type. The results so far indicate that these fields do have a surface expression and that geomicrobial analysis as well as radiometrics and free soil gas can detect hydrocarbon microseepage from pressurized reservoirs. All three exploration techniques located the reservoirs independent of depth, hydrocarbon type, or trapping style.

  7. A simple technique for the measurement of 222Rn in soil gas using LLRDS

    International Nuclear Information System (INIS)

    Karunakara, N.

    2010-01-01

    The details of the technique of soil gas measurement using LLRDS and results obtained for field measurements at different locations of Mangalore and the results of comparative study with the AlphaGuard along with the possible scope for the improvisation are presented and discussed in this paper

  8. Development of enclosure technique of tag gas for in-pile creep test

    International Nuclear Information System (INIS)

    Izaki, Toru; Ichikawa, Shoichi; Soroi, Masatoshi; Ito, Chikara

    2004-01-01

    Outline of the enclosure technique of tag gas for in-pile creep test is stated. In order to carry out in-pile creep test, the sample can enclose tag gas before the test and then the sample is inserted into MARICO-2 (Material Testing Rig with Temperature Control) in FBR 'JOYO' MK-III for the irradiation test. Outline of in-pile creep test using tag gas, enclosure system of tag gas, detection of a part of broken sample and identification of sample are explained. 126-, 128-, 129-, 131-, 132-, and 134-Xe are used as tag gases. The samples are identified by RIMS (Laser Resonance Ionization Mass Spectroscopy) in ppt order. ODS ferritic steel will be tested by the method in the next step. (S.Y.)

  9. Brazing and diffusion bonding processes as available repair techniques for gas turbine blades and nozzles

    International Nuclear Information System (INIS)

    Mazur, Z.

    1997-01-01

    The conventionally welding methods are not useful for repair of heavily damaged gas turbine blades and nozzles. It includes thermal fatigue and craze cracks, corrosion, erosion and foreign object damage, which extend to the large areas. Because of required extensive heat input and couponing, it can cause severe distortion of the parts and cracks in the heat affected zone, and can made the repair costs high. For these cases, the available repair methods of gas turbine blades and nozzles, include brazing and diffusion bonding techniques are presented. Detailed analysis of the brazing and diffusion bonding processes applied for gas turbine blades repair with all elements which presented. Detailed analysis of the brazing and diffusion bonding processes applied for gas turbine blades repair with all elements which have influence to get sound joint is carried out. Depend of kind of blades and nozzle damage or deterioration registered a different methods of brazing and diffusion bonding applicability is presented. (Author) 65 refs

  10. Bose-Einstein condensation in real space

    International Nuclear Information System (INIS)

    Valencia, J.J.; Llano, M. de; Solis, M.A.

    2004-01-01

    We show how Bose-Einstein condensation (BEC) occurs not only in momentum space but also in coordinate (or real) space. Analogies between the isotherms of a van der Waals classical gas of extended (or finite-diameter) identical atoms and the point (or zero-diameter) particles of an ideal BE gas allow concluding that, in contrast with the classical case, the volume per particle vanishes in the pure BE condensate phase precisely because the boson diameters are zero. Thus a BE condensate forms in real space without exhibiting a liquid branch as does the classical gas. (Author)

  11. Application of the can technique and radon gas analyzer for radon exhalation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Fazal-ur-Rehman E-mail: fazalr@kfupm.edu.sa; Al-Jarallah, M.I.; Musazay, M.S.; Abu-Jarad, F

    2003-12-01

    A passive 'can technique' and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bq m{sup -2} h{sup -1} with an average of 1.35{+-}1.40 Bq m{sup -2} h{sup -1}. The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation.

  12. The Dynamics of Aerosols in Condensational Scrubbers

    DEFF Research Database (Denmark)

    Johannessen, Jens Tue; Christensen, Jan A.; Simonsen, Ole

    1997-01-01

    A mathematical model for the simulation of the dynamics of aerosol change in condensational scrubbers and scrubbing condensers is proposed. The model is applicable for packed column gas/liquid contact when plug flow can be assumed. The model is compared with experimental data for particle removal...... for their estimation is proposed. The behaviour of scrubbers and condensers for some important technical applications is demonstrated by model simulations. (C) 1997 Elsevier Science Ltd....

  13. GRAVTool, Advances on the Package to Compute Geoid Model path by the Remove-Compute-Restore Technique, Following Helmert's Condensation Method

    Science.gov (United States)

    Marotta, G. S.

    2017-12-01

    Currently, there are several methods to determine geoid models. They can be based on terrestrial gravity data, geopotential coefficients, astrogeodetic data or a combination of them. Among the techniques to compute a precise geoid model, the Remove Compute Restore (RCR) has been widely applied. It considers short, medium and long wavelengths derived from altitude data provided by Digital Terrain Models (DTM), terrestrial gravity data and Global Geopotential Model (GGM), respectively. In order to apply this technique, it is necessary to create procedures that compute gravity anomalies and geoid models, by the integration of different wavelengths, and adjust these models to one local vertical datum. This research presents the advances on the package called GRAVTool to compute geoid models path by the RCR, following Helmert's condensation method, and its application in a study area. The studied area comprehends the federal district of Brazil, with 6000 km², wavy relief, heights varying from 600 m to 1340 m, located between the coordinates 48.25ºW, 15.45ºS and 47.33ºW, 16.06ºS. The results of the numerical example on the studied area show a geoid model computed by the GRAVTool package, after analysis of the density, DTM and GGM values, more adequate to the reference values used on the study area. The accuracy of the computed model (σ = ± 0.058 m, RMS = 0.067 m, maximum = 0.124 m and minimum = -0.155 m), using density value of 2.702 g/cm³ ±0.024 g/cm³, DTM SRTM Void Filled 3 arc-second and GGM EIGEN-6C4 up to degree and order 250, matches the uncertainty (σ =± 0.073) of 26 points randomly spaced where the geoid was computed by geometrical leveling technique supported by positioning GNSS. The results were also better than those achieved by Brazilian official regional geoid model (σ = ± 0.076 m, RMS = 0.098 m, maximum = 0.320 m and minimum = -0.061 m).

  14. Capillary Condensation in Confined Media

    OpenAIRE

    Charlaix, Elisabeth; Ciccotti, Matteo

    2009-01-01

    28 pages - To appear in 2010 in the Handbook of Nanophysics - Vol 1 - Edited by Klaus Sattler - CRC Press; We review here the physics of capillary condensation of liquids in confined media, with a special regard to the application in nanotechnologies. The thermodynamics of capillary condensation and thin film adsorption are first exposed along with all the relevant notions. The focus is then shifted to the modelling of capillary forces, to their measurements techniques (including SFA, AFM and...

  15. Condensation of exciton polaritons

    International Nuclear Information System (INIS)

    Kasprzak, J.

    2006-10-01

    Because of their unique property of bringing pure quantum effects into the real world scale, phase transitions towards condensed phases - like Bose-Einstein condensation (BEC), superfluidity, and superconductivity - have always fascinated scientists. The BEC, appearing upon cooling a gas of bosons below a critical temperature, has been given a striking demonstration in dilute atomic gases of rubidium atoms at temperatures below 200 nK. By confining photons in a semiconductor micro-cavity, and strongly coupling them to electronic excitations, one may create polaritons. These bosonic quasi-particles are 10 9 times lighter than rubidium atoms, thus theoretically allowing a BEC at standard cryogenic temperatures. Here we detail a comprehensive set of experiments giving compelling evidence for a BEC of polaritons. Above a critical density, we observe massive occupation of the ground state, developing from a thermalized and saturated distribution of the polariton population at (16-20) K. We demonstrate as well the existence of a critical temperature for this transition. The spontaneous onset of a coherent state is manifested by the increase of temporal coherence, the build-up of long-range spatial coherence and the reduction of the thermal noise observed in second order coherence experiments. The marked linear polarization of the emission from the condensate is also measured. All of these findings indicate the spontaneous onset of a macroscopic quantum phase. (author)

  16. Condenser inleakage monitoring system development. Final report

    International Nuclear Information System (INIS)

    Kassen, W.R.; Putkey, T.A.; Sawochka, S.G.; Pearl, W.L.; Clouse, M.E.

    1982-09-01

    An instrument/hardware package for air and condenser cooling water inleakage location employing the helium and freon techniques was designed and fabricated. The package consists of design details for tracer gas distribution hardware, injection plenums, and a sample preconditioner and instrument module. Design of the package was based on an evaluation of helium and freon leak detectors and a survey of utility user's experience with the helium and freon techniques. The applicability of the instrument/hardware package to air and cooling water inleakage location was demonstrated at Pacific Gas and Electric Company's Moss Landing Station. The use of calibrated leaks indicated that cooling water leaks down to 1.5 x 10 -4 gpm (0.56 ml/min) and air leaks down to 0.05 cfm were readily detectable with the helium technique, whereas a 4 x 10 -4 gpm (1.5 ml/min) liquid leak was the readily detectable minimum via the freon technique. The field demonstration and in-house detector testing showed the helium technique to be preferable to the freon technique for inleakage location at PWRs, BWRs, and fossil-fueled systems

  17. A unified approach to assess performance of different techniques for recovering exhaust heat from gas turbines

    International Nuclear Information System (INIS)

    Carapellucci, Roberto

    2009-01-01

    Exhaust heat from gas turbines can be recovered externally or internally to the cycle itself. Of the technology options for external recovery, the combined gas-steam power plant is by far the most effective and commonly used worldwide. For internal recovery conventional solutions are based on thermodynamic regeneration and steam injection, while innovative solutions rely on humid air regeneration and steam reforming of fuel. In this paper a unified approach for analysing different exhaust heat recovery techniques is proposed. It has been possible to define a characteristic internal heat recovery plane, based on a few meaningful parameters and to identify an innovative scheme for repowering existing combined cycles. The characteristic plane indicates directly the performance obtainable with the different recovery techniques, showing that performances close to combined cycle plants (external recovery) can only be achieved with combined recovery techniques (humid air regeneration, steam reforming of fuel). The innovative repowering scheme, which requires the addition of a gas turbine and one-pressure level HRSG to an existing combined gas-steam power plant, significantly increases power output with fairly high marginal efficiency.

  18. Feasibility of a tracer gas technique for containment leakage characterization at Bruce NGS

    International Nuclear Information System (INIS)

    Singh, V.P.

    1985-11-01

    Methods for tracer gas test have been conceived and are proposed for use in conjunction with other techniques used during off-power pressurization tests. During pressurization tests is appears possible to quantify leaks through containment boundaries which make up one of the walls in adjacent rooms but quantification of leaks to open areas will require further development. Several gases may be used as tracers during pressurization tests but the preferred tracer gas is sulphur hexafluoride (SF 6 ) at an in-vault concentration of 100 μL/L if open area sampling is to be carried out of 10 μL/L if only closed room sampling is to be performed. Large values of the ratio (tracer gas concentration in containment/lower detection limit) are necessary for identification of leak sites in open areas having significant ventilation flow. It is recommended that in-station trials be carried out to test the validity of this technique. In addition, a tracer gas technique for use during on-power operation is also proposed but leak site identification and quantification during on-power tests is only possible for containment boundaries which make up the wall(s) of adjacent rooms. The use of SF 6 is required for tests conducted during on-power operation. The recommended in-vault concentration is 10 μL/L. Recommendations are made for future work, including leak tests during on-power operation

  19. Conventional and dense gas techniques for the production of liposomes: a review.

    Science.gov (United States)

    Meure, Louise A; Foster, Neil R; Dehghani, Fariba

    2008-01-01

    The aim of this review paper is to compare the potential of various techniques developed for production of homogenous, stable liposomes. Traditional techniques, such as Bangham, detergent depletion, ether/ethanol injection, reverse-phase evaporation and emulsion methods, were compared with the recent advanced techniques developed for liposome formation. The major hurdles for scaling up the traditional methods are the consumption of large quantities of volatile organic solvent, the stability and homogeneity of the liposomal product, as well as the lengthy multiple steps involved. The new methods have been designed to alleviate the current issues for liposome formulation. Dense gas liposome techniques are still in their infancy, however they have remarkable advantages in reducing the use of organic solvents, providing fast, single-stage production and producing stable, uniform liposomes. Techniques such as the membrane contactor and heating methods are also promising as they eliminate the use of organic solvent, however high temperature is still required for processing.

  20. Characteristics of compressed natural gas jet and jet-wall impingement using the Schlieren imaging technique

    International Nuclear Information System (INIS)

    Ismael, M A; Heikal, M R; Baharom, M B

    2013-01-01

    An experimental study was performed to investigate the compressed natural gas jet characteristics and jet-wall impingement using the Schlieren imaging technique and image processing. An injector driver was used to drive the natural gas injector and synchronized with camera triggering. A constant-volume optical chamber was designed to facilitate maximum optical access for the study of the jet macroscopic characteristics and jet-wall impingement at different injection pressures and injectors-wall distances. Measurement of the jet tip penetration and cone angle at different conditions are presented in this paper together with temporal presentation of the jet radial travel along the wall.

  1. Condensate recovery by cycling at declining pressures

    Energy Technology Data Exchange (ETDEWEB)

    Havlena, Z G; Griffith, J D; Pot, R; Kiel, O G

    1967-06-05

    Cycling condensate reservoirs under conditions of declining pressure, rather than constant pressure, is advantageous from both a recovery and an economic standpoint. Wet gas displaced from the swept areas is recovered concurrently with wet gas recovered by gas expansion from the unswept portions of the reservoir. Any liquid condensed in the swept areas is revaporized by dry injection gas and recovered as an enriched gas. By this mode of operation, high condensate recovery is obtained, gas sales may be possible at an earlier stage of depletion, more flexibility in field and plant operations is feasible and reduction of 15% in investment and operating costs is achieved. Injection gas requirements are reduced by 40%. The Windfall reservoir in Canada has been successfully produced in this manner, starting in 1962. It is a typical retrograde type reservoir which in 1965 represented 15% of reservoirs exploited in North America.

  2. Direct analysis of ultra-trace semiconductor gas by inductively coupled plasma mass spectrometry coupled with gas to particle conversion-gas exchange technique.

    Science.gov (United States)

    Ohata, Masaki; Sakurai, Hiromu; Nishiguchi, Kohei; Utani, Keisuke; Günther, Detlef

    2015-09-03

    An inductively coupled plasma mass spectrometry (ICPMS) coupled with gas to particle conversion-gas exchange technique was applied to the direct analysis of ultra-trace semiconductor gas in ambient air. The ultra-trace semiconductor gases such as arsine (AsH3) and phosphine (PH3) were converted to particles by reaction with ozone (O3) and ammonia (NH3) gases within a gas to particle conversion device (GPD). The converted particles were directly introduced and measured by ICPMS through a gas exchange device (GED), which could penetrate the particles as well as exchange to Ar from either non-reacted gases such as an air or remaining gases of O3 and NH3. The particle size distribution of converted particles was measured by scanning mobility particle sizer (SMPS) and the results supported the elucidation of particle agglomeration between the particle converted from semiconductor gas and the particle of ammonium nitrate (NH4NO3) which was produced as major particle in GPD. Stable time-resolved signals from AsH3 and PH3 in air were obtained by GPD-GED-ICPMS with continuous gas introduction; however, the slightly larger fluctuation, which could be due to the ionization fluctuation of particles in ICP, was observed compared to that of metal carbonyl gas in Ar introduced directly into ICPMS. The linear regression lines were obtained and the limits of detection (LODs) of 1.5 pL L(-1) and 2.4 nL L(-1) for AsH3 and PH3, respectively, were estimated. Since these LODs revealed sufficiently lower values than the measurement concentrations required from semiconductor industry such as 0.5 nL L(-1) and 30 nL L(-1) for AsH3 and PH3, respectively, the GPD-GED-ICPMS could be useful for direct and high sensitive analysis of ultra-trace semiconductor gas in air. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Condensation coefficient of water in a weak condensation state

    International Nuclear Information System (INIS)

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-01-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

  4. Condensation coefficient of water in a weak condensation state

    Science.gov (United States)

    Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo

    2008-07-01

    The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].

  5. Automatic counting of fission fragments tracks using the gas permeation technique

    CERN Document Server

    Yamazaki, I M

    1999-01-01

    An automatic counting system for fission tracks induced in a polycarbonate plastic Makrofol KG (10 mu m thickness) is described. The method is based on the gas transport mechanism proposed by Knudsen, where the gas permeability for a porous membrane is expected to be directly related to its track density. In this work, nitrogen permeabilities for several Makrofol films, with different fission track densities, have been measured using an adequate gas permeation system. The fission tracks were produced by irradiating Makrofol foils with a 252Cf calibrated source in a 2 pi geometry. A calibration curve fission track number versus nitrogen permeability has been obtained, for track densities higher than 1000/cm sup 2 , where the spark gap technique and the visual methods employing a microscope, are not appropriate for track counting.

  6. Radioisotope techniques for problem solving in the offshore oil and gas industry

    International Nuclear Information System (INIS)

    Charlton, J.S.; Hurst, J.A.

    1994-01-01

    Radioisotope technology has been used for almost half a century by the oil and gas industry to solve problems and to help optimize process operations. The use of radioactive isotopes to investigate the effectiveness of well stimulation procedures and to measure the sweep-out patterns of oil and gas in secondary recovery process is well known. The applications of radioisotopes to study features of plant and process operation has been less widely reported though the economic benefits deriving from such applications are very great. Nevertheless, there has been continuous development in the range of application and in the design of equipment to facilitate the use of the technology at remote environments such as an oil or gas platform. Some indication of the current usage of radioisotope techniques may be obtained from examination of Table I, which lists projects carried out in the UK's North Sea fields by ICI Tracerco, which is the world's largest radioisotope applications service group

  7. Development of an in situ calibration technique for combustible gas detectors

    Science.gov (United States)

    Shumar, J. W.; Wynveen, R. A.; Lance, N., Jr.; Lantz, J. B.

    1977-01-01

    This paper describes the development of an in situ calibration procedure for combustible gas detectors (CGD). The CGD will be a necessary device for future space vehicles as many subsystems in the Environmental Control/Life Support System utilize or produce hydrogen (H2) gas. Existing calibration techniques are time-consuming and require support equipment such as an environmental chamber and calibration gas supply. The in situ calibration procedure involves utilization of a water vapor electrolysis cell for the automatic in situ generation of a H2/air calibration mixture within the flame arrestor of the CGD. The development effort concluded with the successful demonstration of in situ span calibrations of a CGD.

  8. Gas Source Techniques for Molecular Beam Epitaxy of Highly Mismatched Ge Alloys

    Directory of Open Access Journals (Sweden)

    Chad A. Stephenson

    2016-12-01

    Full Text Available Ge and its alloys are attractive candidates for a laser compatible with silicon integrated circuits. Dilute germanium carbide (Ge1−xCx offers a particularly interesting prospect. By using a precursor gas with a Ge4C core, C can be preferentially incorporated in substitutional sites, suppressing interstitial and C cluster defects. We present a method of reproducible and upscalable gas synthesis of tetrakis(germylmethane, or (H3Ge4C, followed by the design of a hybrid gas/solid-source molecular beam epitaxy system and subsequent growth of defect-free Ge1−xCx by molecular beam epitaxy (MBE. Secondary ion mass spectroscopy, transmission electron microscopy and contactless electroreflectance confirm the presence of carbon with very high crystal quality resulting in a decrease in the direct bandgap energy. This technique has broad applicability to growth of highly mismatched alloys by MBE.

  9. Ruminal degradation kinetics of protein foods by in vitro gas production technique

    Directory of Open Access Journals (Sweden)

    Ivone Yurika Mizubuti

    2014-02-01

    Full Text Available Chemical analysis of carbohydrates and nitrogen fractions, as well as, determination their carbohydrates digestion rates in soyben meal (SM, crambe meal (CM, radish meal (RM, wet brewery residue (WBR and dehydrated silkworm chrysalis (SCD were accomplished. The kinetics parameters of non-fibrous carbohydrates (NFC and B2 fraction were estimated using cumulative gas production technique. Among the foods studied there was considerable variation in chemical composition. The crambe meal was the only food that did not present synchronism between carbohydrate and nitrogen fractions. In this food there was predominance of A+B1 carbohydrates fractions and B1+B2 nitrogen compounds fraction, and for the other predominated B2 carbohydrate fraction and B1+ B2 nitrogen compounds fraction. There were differences among the digestive kinetic parameters for all foods. The greater participation in gas production due to non-fibrous carbohydrates was found in the crambe meal and oilseed radish meal. The fermentation of fibrous carbohydrates provided higher gas volume in the wet brewery residue and in the soybean meal, however, the soybean meal was food with higher total gas volume. Non fibrous carbohydrates degradation rates of wet brewery residue and dehydrated silkworm chrysalis were far below the limits of degradation of this fraction. Due to the parameters obtained by the cumulative gas production, the soybean meal was the best food, however, all others have potential for use in animal nutrition. The cumulative gas production technique allows the estimative of degradation rates and provides further information about the ruminal fermentation kinetics of foods.

  10. Huff 'n puff to revaporize liquid dropout in an Omani gas field

    Energy Technology Data Exchange (ETDEWEB)

    Al-Wadhahi, M.; Boukadi, F.H.; Al-Bemani, A.; Al-Maamari, R.; Al-Hadrami, H. [Department of Petroleum and Chemical Engineering, Sultan Qaboos University, P.O. Box 33, Al-Khod 123 (Oman)

    2007-01-15

    In this study, Huff 'n Puff technique is used as a production mechanism to revaporize liquid dropout in the Saih Rawl retrograde condensate gas field, Oman. During the huff cycle, a number of wells were shut in to achieve revaporization. The same wells were put on stream, during the puff cycle. Liquid dropout induced a mechanical skin around the wellbore and hampered gas production capabilities but has been revaporized through pressurization. The pressure buildup in the rich-gas condensate reservoir was due to a cross flow originating from a deeper highly pressurized lean-gas bearing formation. The pressure communication was taking place through the wellbore during shut-in cycles. A compositional simulation model was used to confirm the theory of condensate revaporization. Simulation results indicated that Huff 'n Puff is a viable production technique. The technique improved gas deliverability and enhanced gas-liquid production by minimizing the skin caused by gas-liquid dropout. (author)

  11. Sabots, Obturator and Gas-In-Launch Tube Techniques for Heat Flux Models in Ballistic Ranges

    Science.gov (United States)

    Bogdanoff, David W.; Wilder, Michael C.

    2013-01-01

    For thermal protection system (heat shield) design for space vehicle entry into earth and other planetary atmospheres, it is essential to know the augmentation of the heat flux due to vehicle surface roughness. At the NASA Ames Hypervelocity Free Flight Aerodynamic Facility (HFFAF) ballistic range, a campaign of heat flux studies on rough models, using infrared camera techniques, has been initiated. Several phenomena can interfere with obtaining good heat flux data when using this measuring technique. These include leakage of the hot drive gas in the gun barrel through joints in the sabot (model carrier) to create spurious thermal imprints on the model forebody, deposition of sabot material on the model forebody, thereby changing the thermal properties of the model surface and unknown in-barrel heating of the model. This report presents developments in launch techniques to greatly reduce or eliminate these problems. The techniques include the use of obturator cups behind the launch package, enclosed versus open front sabot designs and the use of hydrogen gas in the launch tube. Attention also had to be paid to the problem of the obturator drafting behind the model and impacting the model. Of the techniques presented, the obturator cups and hydrogen in the launch tube were successful when properly implemented

  12. EVALUATION OF SOLVENTS EFFICIENCY IN CONDENSATE BANKING REMOVAL

    OpenAIRE

    CORREA, TOMAS; TIAB, DJEBBAR; RESTREPO, DORA PATRICIA

    2009-01-01

    This work describes experimental design and tests performed to simulate gas condensate reservoir conditions below dew point in the laboratory using three different compositions of synthetic gas condensate. Methanol, propanol and methylene chloride are the solvents used to remove the condensate banking and improve the gas effective permeability near to the wellbore. Solvents are injected in Berea sandstone rock with similar petrophysical properties in order to compare the efficiency at removin...

  13. Gas removal technique to maintain global environment. Chikyu kankyo hozen no tame no bojo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, K [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1992-10-12

    This paper describes the removal technique of gases such as CO2, SO2 and NOx which have the deep relation to the maintenance of global environment. This paper describes partially r SO2 and NOx which are the primary cause of acid rain. As for the removal of CO2 generated from fixed sources (thermal power stations and others), the separation technique and isolation-fixation technique have been researched on and developed. Of the separation method, the effect of the chemical absorption method and the adsorption method is proved with the preceding experiments. The isolation method is differently researched on as to store under deep sea or ground but may be urgent and temporary. The fixation of CO2 is a serious global problem which relates to the afforestation and forests. The fixation which uses coral reefs in ocean as the absorption source has a potential. As for the processing of substances causing acid rain, the desulfurization from petroleum and the flue gas desulfurization have the excellent results. The improvement of combustion method or the flue gas denitrification at the fixed sources are used to remove NOx. The removal of NOx from all diesel cars is difficult compared with the exhaust gas cleaning of gasoline cars and is not commercialized. 11 refs., 1 fig., 2 tabs.

  14. Low temperature techniques for natural gas purification and LNG production: An energy and exergy analysis

    International Nuclear Information System (INIS)

    Baccanelli, Margaret; Langé, Stefano; Rocco, Matteo V.; Pellegrini, Laura A.; Colombo, Emanuela

    2016-01-01

    Highlights: • Low-temperature processes for of high CO_2 content natural gas have been modelled. • Energy and exergy analyses have been performed. • The Dual Pressure distillation scheme has the best thermodynamic performances. • There is a synergy between cryogenic natural gas purification and LNG production. - Abstract: Due to the rapid increase of the World’s primary energy demand of the last decades, low-temperature processes for the purification of natural gas streams with high carbon dioxide content has gained interest, since they allow to make profitable exploitation of low-quality gas reserves. Low temperature purification processes allow the direct production of a methane stream at high purity and at low-temperature, suitable conditions for the direct synergistic integration with natural gas cryogenic liquefaction processes, while CO_2 is obtained in liquid phase and under pressure. In this way, it can be pumped for transportation, avoiding significant compression costs as for classical CO_2 capture units (where carbon dioxide is discharged in gas phase and at atmospheric pressure), and further uses such as Enhanced Oil Recovery (EOR) or underground storage. In this paper, the three most common natural gas low-temperature purification techniques have been modelled and their performances have been evaluated through energy and exergy analyses. Specifically, the dual pressure low-temperature distillation process, the anti-sublimation process and a hybrid configuration have been considered. It is found that the dual pressure low-temperature distillation scheme reach the highest thermodynamic performances, resulting in the best values of exergy efficiency and equivalent methane requirements with respect to the other configurations. This is mainly due to the distributed temperature profile along a distillation column, resulting in a less irreversible heat exchanging process.

  15. Towards the development of rapid screening techniques for shale gas core properties

    Science.gov (United States)

    Cave, Mark R.; Vane, Christopher; Kemp, Simon; Harrington, Jon; Cuss, Robert

    2013-04-01

    Shale gas has been produced for many years in the U.S.A. and forms around 8% of total their natural gas production. Recent testing for gas on the Fylde Coast in Lancashire UK suggests there are potentially large reserves which could be exploited. The increasing significance of shale gas has lead to the need for deeper understanding of shale behaviour. There are many factors which govern whether a particular shale will become a shale gas resource and these include: i) Organic matter abundance, type and thermal maturity; ii) Porosity-permeability relationships and pore size distribution; iii) Brittleness and its relationship to mineralogy and rock fabric. Measurements of these properties require sophisticated and time consuming laboratory techniques (Josh et al 2012), whereas rapid screening techniques could provide timely results which could improve the efficiency and cost effectiveness of exploration. In this study, techniques which are portable and provide rapid on-site measurements (X-ray Fluorescence (XRF) and Infra-red (IR) spectroscopy) have been calibrated against standard laboratory techniques (Rock-Eval 6 analyser-Vinci Technologies) and Powder whole-rock XRD analysis was carried out using a PANalytical X'Pert Pro series diffractometer equipped with a cobalt-target tube, X'Celerator detector and operated at 45kV and 40mA, to predict properties of potential shale gas material from core material from the Bowland shale Roosecote, south Cumbria. Preliminary work showed that, amongst various mineralogical and organic matter properties of the core, regression models could be used so that the total organic carbon content could be predicted from the IR spectra with a 95 percentile confidence prediction error of 0.6% organic carbon, the free hydrocarbons could be predicted with a 95 percentile confidence prediction error of 0.6 mgHC/g rock, the bound hydrocarbons could be predicted with a 95 percentile confidence prediction error of 2.4 mgHC/g rock, mica content

  16. Condensation model for the ESBWR passive condensers

    International Nuclear Information System (INIS)

    Revankar, S. T.; Zhou, W.; Wolf, B.; Oh, S.

    2012-01-01

    In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data from separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)

  17. Condensate from a two-stage gasifier

    DEFF Research Database (Denmark)

    Bentzen, Jens Dall; Henriksen, Ulrik Birk; Hindsgaul, Claus

    2000-01-01

    Condensate, produced when gas from downdraft biomass gasifier is cooled, contains organic compounds that inhibit nitrifiers. Treatment with activated carbon removes most of the organics and makes the condensate far less inhibitory. The condensate from an optimised two-stage gasifier is so clean...... that the organic compounds and the inhibition effect are very low even before treatment with activated carbon. The moderate inhibition effect relates to a high content of ammonia in the condensate. The nitrifiers become tolerant to the condensate after a few weeks of exposure. The level of organic compounds...... and the level of inhibition are so low that condensate from the optimised two-stage gasifier can be led to the public sewer....

  18. The influence of N-7 guanine modifications on the strength of Watson-Crick base pairing and guanine N-1 acidity: Comparison of gas-phase and condensed-phase trends

    Czech Academy of Sciences Publication Activity Database

    Burda, J. V.; Šponer, Jiří; Hrabáková, J.; Zeizinger, M.; Leszczynski, J.

    2003-01-01

    Roč. 107, č. 22 (2003), s. 5349-5356 ISSN 1520-6106 R&D Projects: GA MŠk ME 517; GA MŠk LN00A016 Grant - others:Wellcome Trust(GB) GR067507MF; ONR(US) N00034-03-1-0116; National Science Foundation(US) CREST 9805465 Institutional research plan: CEZ:AV0Z5004920 Keywords : Watson-Crick base pairing * guanines * gas-phase and condensed-phase trends Subject RIV: BO - Biophysics Impact factor: 3.679, year: 2003

  19. Condensation: the new deal; Condensation: la nouvelle donne

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-01

    The principle of condensation boilers is based on the recovery of the latent heat of the steam generated by the combustion of natural gas. This technology was introduced in France at the end of the 80's but failed in its promise because of the complexity of the equipments available at that time. Today, constructors' offer is more mature and reliable and the context has changed. This technology can conciliate three goals: a mastery of energy consumptions, the comfort of the user and the respect of environment. This meeting organized by the research center of Gaz de France (Cegibat), was a good opportunity to makes a status of the market of individual condensation systems in France and in Europe, to present the situation of this technology today and the 10 golden rules for the fitting and maintenance of individual condensation boilers, and to present some technical references, examples and results of today's offer. (J.S.)

  20. Adaptive polynomial chaos techniques for uncertainty quantification of a gas cooled fast reactor transient

    International Nuclear Information System (INIS)

    Perko, Z.; Gilli, L.; Lathouwers, D.; Kloosterman, J. L.

    2013-01-01

    Uncertainty quantification plays an increasingly important role in the nuclear community, especially with the rise of Best Estimate Plus Uncertainty methodologies. Sensitivity analysis, surrogate models, Monte Carlo sampling and several other techniques can be used to propagate input uncertainties. In recent years however polynomial chaos expansion has become a popular alternative providing high accuracy at affordable computational cost. This paper presents such polynomial chaos (PC) methods using adaptive sparse grids and adaptive basis set construction, together with an application to a Gas Cooled Fast Reactor transient. Comparison is made between a new sparse grid algorithm and the traditionally used technique proposed by Gerstner. An adaptive basis construction method is also introduced and is proved to be advantageous both from an accuracy and a computational point of view. As a demonstration the uncertainty quantification of a 50% loss of flow transient in the GFR2400 Gas Cooled Fast Reactor design was performed using the CATHARE code system. The results are compared to direct Monte Carlo sampling and show the superior convergence and high accuracy of the polynomial chaos expansion. Since PC techniques are easy to implement, they can offer an attractive alternative to traditional techniques for the uncertainty quantification of large scale problems. (authors)

  1. Thermodynamic assessment of impact of inlet air cooling techniques on gas turbine and combined cycle performance

    International Nuclear Information System (INIS)

    Mohapatra, Alok Ku; Sanjay

    2014-01-01

    The article is focused on the comparison of impact of two different methods of inlet air cooling (vapor compression and vapor absorption cooling) integrated to a cooled gas turbine based combined cycle plant. Air-film cooling has been adopted as the cooling technique for gas turbine blades. A parametric study of the effect of compressor pressure ratio, compressor inlet temperature (T i , C ), turbine inlet temperature (T i , T ), ambient relative humidity and ambient temperature on performance parameters of plant has been carried out. Optimum T i , T corresponding to maximum plant efficiency of combined cycle increases by 100 °C due to the integration of inlet air cooling. It has been observed that vapor compression cooling improves the efficiency of gas turbine cycle by 4.88% and work output by 14.77%. In case of vapor absorption cooling an improvement of 17.2% in gas cycle work output and 9.47% in gas cycle efficiency has been observed. For combined cycle configuration, however, vapor compression cooling should be preferred over absorption cooling in terms of higher plant performance. The optimum value of compressor inlet temperature has been observed to be 20 °C for the chosen set of conditions for both the inlet air cooling schemes. - Highlights: • Inlet air cooling improves performance of cooled gas turbine based combined cycle. • Vapor compression inlet air cooling is superior to vapor absorption inlet cooling. • For every turbine inlet temperature, there exists an optimum pressure ratio. • The optimum compressor inlet temperature is found to be 293 K

  2. Japan does it mainly compact and flexible: Innovate improvements in the natural gas distribution technique and gas appliances

    International Nuclear Information System (INIS)

    Roebers, H.

    1994-01-01

    Specific Japanese innovative improvements in natural gas distribution systems and natural gas appliances are outlined, based on the KAI-ZEN philosophy. Attention is paid to the design of flexible gas pipes, gas plug-in sockets, and safety systems, and the compact design of gas appliances. Much of the innovations focus on details. Briefly, the NEXT 21 project is described, which project anticipates the silent wishes of the Japanese people with regard to lifestyle

  3. Enhanced Condensation Heat Transfer

    Science.gov (United States)

    Rose, John Winston

    The paper gives some personal observations on various aspects of enhanced condensation heat transfer. The topics discussed are external condensation (horizontal low-finned tubes and wire-wrapped tubes), internal condensation (microfin tubes and microchannels) and Marangoni condensation of binary mixtures.

  4. A novel decomposition technique of friable asbestos by CHClF2-decomposed acidic gas

    International Nuclear Information System (INIS)

    Yanagisawa, Kazumichi; Kozawa, Takahiro; Onda, Ayumu; Kanazawa, Masazumi; Shinohara, Junichi; Takanami, Tetsuro; Shiraishi, Masatsugu

    2009-01-01

    Asbestos was widely used in numerous materials and building products due to their desirable properties. It is, however, well known that asbestos inhalation causes health damage and its inexpensive decomposition technique is necessary to be developed for pollution prevention. We report here an innovative decomposition technique of friable asbestos by acidic gas (HF and HCl) generated from the decomposition of CHClF 2 by the reaction with superheated steam at 800 deg. C. Chrysotile-asbestos fibers were completely decomposed to sellaite and magnesium silicofluoride hexahydrate by the reaction with CHClF 2 -decomposed acidic gas at 150 deg. C for 30 min. At high temperatures beyond 400 deg. C, sellaite and hematite were detected in the decomposed product. In addition, crocidolite containing wastes and amosite containing wastes were decomposed at 500 deg. C and 600 deg. C for 30 min, respectively, by CHClF 2 -decomposed acidic gas. The observation of the reaction products by phase-contrast microscopy (PCM) and scanning electron microscopy (SEM) confirmed that the resulting products did not contain any asbestos

  5. Condensation on Superhydrophobic Copper Oxide Nanostructures

    OpenAIRE

    Enright, Ryan; Miljkovic, Nenad; Dou, Nicholas; Nam, Youngsuk; Wang, Evelyn N.

    2013-01-01

    Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]. In this work, we investigated a scalable synthesis technique to produce oxide nanostructures on copper surfaces capable of sustaining superhydrophobic condensation and characterized the growth an...

  6. Application of a support vector machine algorithm to the safety precaution technique of medium-low pressure gas regulators

    Science.gov (United States)

    Hao, Xuejun; An, Xaioran; Wu, Bo; He, Shaoping

    2018-02-01

    In the gas pipeline system, safe operation of a gas regulator determines the stability of the fuel gas supply, and the medium-low pressure gas regulator of the safety precaution system is not perfect at the present stage in the Beijing Gas Group; therefore, safety precaution technique optimization has important social and economic significance. In this paper, according to the running status of the medium-low pressure gas regulator in the SCADA system, a new method for gas regulator safety precaution based on the support vector machine (SVM) is presented. This method takes the gas regulator outlet pressure data as input variables of the SVM model, the fault categories and degree as output variables, which will effectively enhance the precaution accuracy as well as save significant manpower and material resources.

  7. Steam blowdown experiments with the condensation pool test rig

    International Nuclear Information System (INIS)

    Purhonen, H.; Puustinen, M.; Laine, J.; Raesaenen, A.; Kyrki-Rajamaeki, R.; Vihavainen, J.

    2005-01-01

    During a possible loss-of-coolant accident (Local) a large amount of non-condensable (nitrogen) and condensable (steam) gas is blown from the upper drywell of the containment to the condensation pool through the blowdown pipes at the boiling water reactors (BWRs). The wet well pool serves as the major heat sink for condensation of steam. The blowdown causes both dynamic and structural loads to the condensation pool. There might also be a risk that the gas discharging to the pool could push its way to the emergency core cooling systems (ECCS) and undermine their performance. (author)

  8. Distribution of gas hydrate inhibitor monoethylene glycol in condensate and water systems: Experimental measurement and thermodynamic modeling using the cubic-plus-association equation of state

    DEFF Research Database (Denmark)

    Riaz, Muhammad; Yussuf, Mustafe A.; Frost, Michael

    2014-01-01

    The deepwater energy sector represents one of the major growth areas of the oil and gas industry today. To meet the challenges of hydrate formation, corrosion, scaling, and foaming, the oil and gas industry uses many chemicals and their use has increased significantly over the years. To inhibit gas...

  9. Gas exchange at the air-sea interface: a technique for radon measurements in seawater

    International Nuclear Information System (INIS)

    Queirazza, G.; Roveri, M.

    1991-01-01

    The rate of exchange of various gas species, such as O 2 , CO 2 etc. across the air-water interface can be evaluated from the 222 Rn vertical profiles in the water column. Radon profiles were measured in 4 stations in the NW Adriatic Sea, in September 1990, using solvent extraction and liquid scintillation counting techniques, directly on board the ship. The radiochemical procedure is described in detail. The lower limit of detection is approximately 0.4 mBq 1 -1 . The radon deficiency in the profiles gives estimates of the gas transfer rate across the air-sea interface ranging from 0.9 to 7.0 m d -1 . The suitability of the radon deficiency method in shallow water, enclosed seas is briefly discussed. (Author)

  10. Measurement of denitrification on grassland using gas chromatography and 15N tracer technique

    International Nuclear Information System (INIS)

    Lippold, H.; Foerster, I.; Hagemann, O.; Matzel, W.

    1981-01-01

    Alternative covering of grassland micro-plots fertilized with 15 NH 4 15 NO 3 allowed on the basis on N 2 and N 2 O quantities released within several weeks to measure denitrification and to calculate it by means of methane as gas tracer. Thus the gas exchange was rendered visible and the N quantities measured could be corrected. In some variants, the acetylene blocking technique was successfully applied by adding acetylene to the soil air. The losses measured at 6 dates are discussed together with the 15 N balance and atmospherical conditions. The method is suited for recording the high losses occurring mainly in the second quarter of the year immediately after fertilization. Under the conditions mentioned soil N losses were small (3 kg N/ha). The immobilized fertilizer N quantities reached 20 to 30 kg/ha (fertilizer rate 100 kg N/ha) and were comparably independent of the date of fertilization. (author)

  11. Experimental investigation on improving the removal effect of WFGD system on fine particles by heterogeneous condensation

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Jingjing; Yang, Linjun; Yan, Jinpei; Xiong, Guilong; Shen, Xianglin [Southeast Univ., Nanjing (China). School of Energy and Environment

    2013-07-01

    Heterogeneous condensation of water vapor as a preconditioning technique for the removal of fine particles from flue gas was investigated experimentally in a wet flue gas desulfurization (WFGD) system. A supersaturated vapor phase, necessary for condensational growth of fine particles, was achieved in the SO{sub 2} absorption zone and at the top of the wet FGD scrubber by adding steam in the gas inlet and above the scrubbing liquid inlet of the scrubber, respectively. The condensational grown droplets were then removed by the scrubbing liquid and a high-efficiency demister. The results show that the effectiveness of the WFGD system for removal of fine particles is related to the SO{sub 2} absorbent and the types of scrubber employed. Despite a little better effectiveness for the removal of fine particles in the rotating-stream-tray scrubber at the same liquid-to-gas ratio, The similar trends are obtained between the spray scrubber and rotating-stream-tray scrubber. Due to the formation of aerosol particles in the limestone and ammonia-based FGD processes, the fine particle removal efficiencies are lower than those for Na{sub 2}CO{sub 3} and water. The performance of the WFGD system for removal of fine particles can be significantly improved for both steam addition cases, for which the removal efficiency increases with increasing amount of added steam. A high liquid to gas ratio is beneficial for efficient removal of fine particles by heterogeneous condensation of water vapor.

  12. Analytical Modelling of the Effects of Different Gas Turbine Cooling Techniques on Engine Performance =

    Science.gov (United States)

    Uysal, Selcuk Can

    In this research, MATLAB SimulinkRTM was used to develop a cooled engine model for industrial gas turbines and aero-engines. The model consists of uncooled on-design, mean-line turbomachinery design and a cooled off-design analysis in order to evaluate the engine performance parameters by using operating conditions, polytropic efficiencies, material information and cooling system details. The cooling analysis algorithm involves a 2nd law analysis to calculate losses from the cooling technique applied. The model is used in a sensitivity analysis that evaluates the impacts of variations in metal Biot number, thermal barrier coating Biot number, film cooling effectiveness, internal cooling effectiveness and maximum allowable blade temperature on main engine performance parameters of aero and industrial gas turbine engines. The model is subsequently used to analyze the relative performance impact of employing Anti-Vortex Film Cooling holes (AVH) by means of data obtained for these holes by Detached Eddy Simulation-CFD Techniques that are valid for engine-like turbulence intensity conditions. Cooled blade configurations with AVH and other different external cooling techniques were used in a performance comparison study. (Abstract shortened by ProQuest.).

  13. Rate transient analysis for homogeneous and heterogeneous gas reservoirs using the TDS technique

    International Nuclear Information System (INIS)

    Escobar, Freddy Humberto; Sanchez, Jairo Andres; Cantillo, Jose Humberto

    2008-01-01

    In this study pressure test analysis in wells flowing under constant wellbore flowing pressure for homogeneous and naturally fractured gas reservoir using the TDS technique is introduced. Although, constant rate production is assumed in the development of the conventional well test analysis methods, constant pressure production conditions are sometimes used in the oil and gas industry. The constant pressure technique or rate transient analysis is more popular reckoned as decline curve analysis under which rate is allows to decline instead of wellbore pressure. The TDS technique, everyday more used even in the most recognized software packages although without using its trade brand name, uses the log-log plot to analyze pressure and pressure derivative test data to identify unique features from which exact analytical expression are derived to easily estimate reservoir and well parameters. For this case, the fingerprint characteristics from the log-log plot of the reciprocal rate and reciprocal rate derivative were employed to obtain the analytical expressions used for the interpretation analysis. Many simulation experiments demonstrate the accuracy of the new method. Synthetic examples are shown to verify the effectiveness of the proposed methodology

  14. Application of ultrasonic testing technique to detect gas accumulation in important pipings for pressurized water reactors safety

    Energy Technology Data Exchange (ETDEWEB)

    Fushimi, Yasuyuki [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2002-09-01

    Since 1988, the USNRC has pointed out that gas-binding events might occur at high head safety injection (HHSI) pumps of pressurized water reactors (PWRs). In Japanese PWR plants, corrective actions were taken in response to gas-binding events that occurred on HHSI pumps in the USA, so no gas accumulation event has been reported so far. However, when venting frequency is prolonged with operating cycle extension, the probability of gas accumulation in pipings may increase as in the USA. The purpose of this study was to establish a technique to identify gas accumulation and to measure the gas volume accurately. Taking dominant causes of the gas-binding events in the USA into consideration, we pointed out the following sections in the Japanese PWRs where gas srtipping and/or gas accumulation might occur: residual heat removal system pipings and charging/safety injection pump minimum flow line. Then an ultrasonic testing technique, adopted to identify gas accumulation in the USA, was applied to those sections of the typical Japanese PWR. Consequently, no gas accumulation was found in those pipings. (author)

  15. UV and condensation technology for applications in the UOG for removal of air contaminants

    Energy Technology Data Exchange (ETDEWEB)

    De Visscher, A.; Langford, C.H. [Calgary Univ., AB (Canada)

    2008-07-01

    Canadian emissions of volatile organic compounds (VOC) are significant. In 2006, the upstream oil and gas (UOG) industry in Canada emitted over 500,000 tonnes of volatile organic compounds per year. 2002 benzene emissions from glycol dehydration units in Canada were estimated at 1,988 tonnes. These emissions are from a large number of sources typically emitting a few tonnes per year. Although condensation systems can reduce emissions, they leave residual emissions. New technologies to reduce emissions would have to be fairly inexpensive and simple given the large number of sources. This presentation addressed two research questions, notably how to predict condensation unit efficiency; and the feasibility of photolysis in UOG waste gas treatment, including glycol dehydration emissions. The presentation discussed the objectives of the study, which were to develop capability to predict efficiencies of condensation units; to develop proof-of-concept of effective ultraviolet technology for treating benzene and other VOCs from upstream oil and gas; and to test the technique for hydrogen sulphide. The presentation discussed the prediction of benzene condensation including the problem, hypothesis, and proposed approach. An introduction to photolysis was also provided. Some chemical reactions of benzene photolysis were demonstrated. Several illustrations were used to show a benzene photolysis reactor; a photocatalytic alternative; and a radiation field simulation model. It was concluded that a predictive model for efficiency of condensation for benzene emission reduction from glycol dehydration units will be developed accounting for non-steady behaviour. 4 figs.

  16. Bose-Einstein condensation of paraxial light

    OpenAIRE

    Klaers, J.; Schmitt, J.; Damm, T.; Vewinger, F.; Weitz, M.

    2011-01-01

    Photons, due to the virtually vanishing photon-photon interaction, constitute to very good approximation an ideal Bose gas, but owing to the vanishing chemical potential a (free) photon gas does not show Bose-Einstein condensation. However, this is not necessarily true for a lower-dimensional photon gas. By means of a fluorescence induced thermalization process in an optical microcavity one can achieve a thermal photon gas with freely adjustable chemical potential. Experimentally, we have obs...

  17. Wire-mesh and ultrasound techniques applied for the characterization of gas-liquid slug flow

    Energy Technology Data Exchange (ETDEWEB)

    Ofuchi, Cesar Y.; Sieczkowski, Wytila Chagas; Neves Junior, Flavio; Arruda, Lucia V.R.; Morales, Rigoberto E.M.; Amaral, Carlos E.F.; Silva, Marco J. da [Federal University of Technology of Parana, Curitiba, PR (Brazil)], e-mails: ofuchi@utfpr.edu.br, wytila@utfpr.edu.br, neves@utfpr.edu.br, lvrarruda@utfpr.edu.br, rmorales@utfpr.edu.br, camaral@utfpr.edu.br, mdasilva@utfpr.edu.br

    2010-07-01

    Gas-liquid two-phase flows are found in a broad range of industrial applications, such as chemical, petrochemical and nuclear industries and quite often determine the efficiency and safety of process and plants. Several experimental techniques have been proposed and applied to measure and quantify two-phase flows so far. In this experimental study the wire-mesh sensor and an ultrasound technique are used and comparatively evaluated to study two-phase slug flows in horizontal pipes. The wire-mesh is an imaging technique and thus appropriated for scientific studies while ultrasound-based technique is robust and non-intrusive and hence well suited for industrial applications. Based on the measured raw data it is possible to extract some specific slug flow parameters of interest such as mean void fraction and characteristic frequency. The experiments were performed in the Thermal Sciences Laboratory (LACIT) at UTFPR, Brazil, in which an experimental two-phase flow loop is available. The experimental flow loop comprises a horizontal acrylic pipe of 26 mm diameter and 9 m length. Water and air were used to produce the two phase flow under controlled conditions. The results show good agreement between the techniques. (author)

  18. Measuring the diameter of rising gas bubbles by means of the ultrasound transit time technique

    Energy Technology Data Exchange (ETDEWEB)

    Richter, T., E-mail: Thomas.Richter6@tu-dresden.de; Eckert, K., E-mail: Kerstin.Eckert@tu-dresden.de; Yang, X.; Odenbach, S.

    2015-09-15

    Highlights: • Ultrasound transit time technique (UTTT) is applied to the zig-zag raise of gas bubble. • Comparison of bubble diameter and tilt, measured by UTTT, with high-speed imaging. • Uncertainty in the determination of the bubble diameter by UTTT is less than 7%. • UTTT is able to measure dynamic changes in bubble size in opaque liquids and vessels. • UTTT can be applied to liquid metal loops. - Abstract: This study presents ultrasound transit time technique (UTTT) measurements of the diameter variations of single argon bubbles rising in a zig-zag trajectory in water. Simultaneous size measurements with a high-speed camera show that UTTT resolves both the apparent diameter and the tilt of the bubble axis with an accuracy of better than 7%. This qualifies UTTT for the measurement of bubble sizes in opaque liquids, such as liquid metals, or vessels.

  19. Systematic comparison of static and dynamic headspace sampling techniques for gas chromatography.

    Science.gov (United States)

    Kremser, Andreas; Jochmann, Maik A; Schmidt, Torsten C

    2016-09-01

    Six automated, headspace-based sample preparation techniques were used to extract volatile analytes from water with the goal of establishing a systematic comparison between commonly available instrumental alternatives. To that end, these six techniques were used in conjunction with the same gas chromatography instrument for analysis of a common set of volatile organic carbon (VOC) analytes. The methods were thereby divided into three classes: static sampling (by syringe or loop), static enrichment (SPME and PAL SPME Arrow), and dynamic enrichment (ITEX and trap sampling). For PAL SPME Arrow, different sorption phase materials were also included in the evaluation. To enable an effective comparison, method detection limits (MDLs), relative standard deviations (RSDs), and extraction yields were determined and are discussed for all techniques. While static sampling techniques exhibited sufficient extraction yields (approx. 10-20 %) to be reliably used down to approx. 100 ng L(-1), enrichment techniques displayed extraction yields of up to 80 %, resulting in MDLs down to the picogram per liter range. RSDs for all techniques were below 27 %. The choice on one of the different instrumental modes of operation (aforementioned classes) was thereby the most influential parameter in terms of extraction yields and MDLs. Individual methods inside each class showed smaller deviations, and the least influences were observed when evaluating different sorption phase materials for the individual enrichment techniques. The option of selecting specialized sorption phase materials may, however, be more important when analyzing analytes with different properties such as high polarity or the capability of specific molecular interactions. Graphical Abstract PAL SPME Arrow during the extraction of volatile analytes from the headspace of an aqueous sample.

  20. Evaluation of three gas chromatography and two direct mass spectrometry techniques for aroma analysis of dried red bell peppers

    NARCIS (Netherlands)

    Ruth, van S.M.; Boscaini, E.; Mayr, D.; Pugh, J.; Posthumus, M.A.

    2003-01-01

    Three gas chromatography methods and two direct mass spectrometry techniques were compared for the analysis of the aroma of rehydrated diced red bell peppers. Gas chromatography methods included systems with olfactometry detection (GC-O), flame ionisation detection (GC-FID) and mass spectrometry

  1. A Robust and Low-Complexity Gas Recognition Technique for On-Chip Tin-Oxide Gas Sensor Array

    Directory of Open Access Journals (Sweden)

    Farid Flitti

    2008-01-01

    Full Text Available Gas recognition is a new emerging research area with many civil, military, and industrial applications. The success of any gas recognition system depends on its computational complexity and its robustness. In this work, we propose a new low-complexity recognition method which is tested and successfully validated for tin-oxide gas sensor array chip. The recognition system is based on a vector angle similarity measure between the query gas and the representatives of the different gas classes. The latter are obtained using a clustering algorithm based on the same measure within the training data set. Experimented results on our in-house gas sensors array show more than 98% of correct recognition. The robustness of the proposed method is tested by recognizing gas measurements with simulated drift. Less than 1% of performance degradation is noted at the worst case scenario which represents a significant improvement when compared to the current state-of-the-art.

  2. Chemical reactions of fission products with ethylene using the gas jet technique

    International Nuclear Information System (INIS)

    Contis, E.T.; Rengan, Krish; Griffin, Henry C.

    1994-01-01

    An understanding of the nature of the chemical reactions taking place between fission products and their carrier gases, and the designing of a fast separation procedure were the purposes of this investigation. Chemical reactions of short-lived (less than one minute half-life) fission products with carrier gases lead to various chemical species which can be separated in the gas phase. The Gas Jet Facility at the Ford Nuclear Reactor was used to study the yields of volatile selenium and bromine fission products of 235 U using a semi-automatic batch solvent extraction technique. Heptane and water were used as organic and inorganic solvents. A carrier gas mixture of ethylene to pre-purified nitrogen (1 : 3) was used to sweep the fission products from the target to the chemistry area for analysis. The results indicated that the volatile selenium products generated by the interaction of selenium fission fragments with ethylene were predominantly organic in nature (84%), possibly organoselenides. The selenium values were used to resolve the fractions of the bromine nuclides, which come from two major sources, viz., directly from fission and from the beta-decay of selenium. The data showed that the fractions of independent bromine fission products in the organic phase were much lower compared to selenium; the bromine values range from 10 to 22% and varied with mass number. Results indicated that the bromine products were inorganic in nature, as possibly hydrogen chloride. ((orig.))

  3. Radioisotope techniques for process optimisation and control in the offshore oil and gas industries

    International Nuclear Information System (INIS)

    Charlton, J.S.

    2002-01-01

    For over fifty years, radioisotope technology has been used by the oil industry to solve problems and to help optimise process operations. The widespread development of offshore oil and gas fields has brought, and continues to bring, new challenges and, in response, new or modified applications of radioisotope technology have been introduced. This paper presents case studies, which illustrate the use of radioisotopes, both in the sub-sea environment and on the offshore production platforms. On the platform, radioisotope techniques applied singly or in combination, have been applied to the performance assessment of oil/gas separation and gas dehydration units. Novel nucleonic instrumentation has been developed for the control of three-phase separators. Sub-sea, radioactive tracers and/or sealed sources have been used to investigate the integrity of submerged structures and to troubleshoot pipeline problems. The continuing expansion in the use of this technology stems from industry increasing awareness of its versatility and from the fact that the benefits it confers can be obtained at a relatively modest cost. Examples of economic benefit described in the paper are associated with production enhancements derived from the ability of radioisotope technology to measure performance and diagnose problems on line, without disrupting process operations in any way. (Author)

  4. Studying gas-sheared liquid film in horizontal rectangular duct with laser-induced fluorescence technique

    Science.gov (United States)

    Cherdantsev, Andrey; Hann, David; Azzopardi, Barry

    2013-11-01

    High-speed LIF-technique is applied to study gas-sheared liquid film in horizontal rectangular duct with 161 mm width. Instantaneous distributions of film thickness resolved in both longitudinal and transverse coordinates were obtained with a frequency of 10 kHz and spatial resolution from 0.125 mm to 0.04 mm. Processes of generation of fast and slow ripples by disturbance waves are the same as described in literature for downwards annular pipe flow. Disturbance waves are often localized by transverse coordinate and may have curved or slanted fronts. Fast ripples, covering disturbance waves, are typically horseshoe-shaped and placed in staggered order. Their characteristic transverse size is of order 1 cm and it decreases with gas velocity. Entrainment of liquid from film surface can also be visualized. Mechanisms of ripple disruption, known as ``bag break-up'' and ``ligament break-up,'' were observed. Both mechanisms may occur on the same disturbance waves. Various scenarios of droplet deposition on the liquid film are observed, including the impact, slow sinking and bouncing, characterized by different outcome of secondary droplets or entrapped bubbles. Number and size of bubbles increase greatly inside the disturbance waves. Both quantities increase with gas and liquid flow rates. EPSRC Programme Grant MEMPHIS (EP/K003976/1), and Roll-Royce UTC (Nottingham, for access to flow facility).

  5. Condensed Matter Nuclear Science

    Science.gov (United States)

    Biberian, Jean-Paul

    2006-02-01

    into characteristics of X-ray emission laser beams from solidstate cathode medium of high-current glow discharge / A. B. Karabut. Charged particles from Ti and Pd foils / L. Kowalski ... [et al.]. Cr-39 track detectors in cold fusion experiments: review and perspectives / A. S. Roussetski. Energetic particle shower in the vapor from electrolysis / R. A. Oriani and J. C. Fisher. Nuclear reactions produced in an operating electrolysis cell / R. A. Oriani and J. C. Fisher. Evidence of microscopic ball lightning in cold fusion experiments / E. H. Lewis. Neutron emission from D[symbol] gas in magnetic fields under low temperature / T. Mizuno ... [et al.]. Energetic charged particle emission from hydrogen-loaded Pd and Ti cathodes and its enhancement by He-4 implantation / A. G. Lipson ... [et al.]. H-D permeation. Observation of nuclear transmutation reactions induced by D[symbol] gas permeation through Pd complexes / Y. Iwamura ... [et al.]. Deuterium (hydrogen) flux permeating through palladium and condensed matter nuclear science / Q. M. Wei ... [et al.]. Triggering. Precursors and the fusion reactions in polarized Pd/D-D[symbol]O system: effect of an external electric field / S. Szpak, P. A. Mosier-Boss, and F. E. Gordon. Calorimetric and neutron diagnostics of liquids during laser irradiation / Yu. N. Bazhutov ... [et al.]. Anomalous neutron capture and plastic deformation of Cu and Pd cathodes during electrolysis in a weak thermalized neutron field: evidence of nuclei-lattice exchange / A. G. Lipson and G. H. Miley. H-D loading. An overview of experimental studies on H/Pd over-loading with thin Pd wires and different electrolytic solutions / A. Spallone ... [et al.] -- 3. Transmutations. Photon and particle emission, heat production, and surface transformation in Ni-H system / E. Campari ... [et al.]. Surface analysis of hydrogen-loaded nickel alloys / E. Campari ... [et al.]. Low-energy nuclear reactions and the leptonic monopole / G. Lochak and L. Urutskoev. Results

  6. Research progress of control of condensate depression for condenser

    Science.gov (United States)

    Liu, Ying; Liang, Run; Li, Fengyu

    2017-08-01

    It is introduced that significance and structure of the condensate depression control system. In accordance with controller devised procedure, we analyze and elaborate how to construct the lumped parameter and dynamic mathematical model which possesses distinct physics significance. Neural network model being called black-box model is also introduced. We analyze and contrast the control technique of condensate depression as conventional PI control, fuzzy PI control and fuzzy control. It is indicated that if the controller of condensate depression were devised inappropriate, while the steam discharged of turbine varying by a large margin, would result in the rotation rate of cooling water circulating pump accelerating at a great lick even to trigger the galloping danger which is less impressive for the units operating safely.

  7. Evaluation of a subsurface oxygenation technique using colloidal gas aphron injections into packed column reactors

    International Nuclear Information System (INIS)

    Wills, R.A.; Coles, P.

    1991-11-01

    Bioremediation may be a remedial technology capable of decontaminating subsurface environments. The objective of this research was to evaluate the use of colloidal gas aphron (CGA) injection, which is the injection of micrometer-size air bubbles in an aqueous surfactant solution, as a subsurface oxygenation technique to create optimal growth conditions for aerobic bacteria. Along with this, the capability of CGAs to act as a soil-washing agent and free organic components from a coal tar-contaminated matrix was examined. Injection of CGAs may be useful for remediation of underground coal gasification (UCG) sites. Because of this, bacteria and solid material from a UCG site located in northeastern Wyoming were used in this research. Colloidal gas aphrons were generated and pumped through packed column reactors (PCRS) containing post-burn core materials. For comparison, PCRs containing sand were also studied. Bacteria from this site were tested for their capability to degrade phenol, a major contaminant at the UCG site, and were also used to bioaugment the PCR systems. In this study we examined: (1) the effect of CGA injection on dissolved oxygen concentrations in the PCR effluents, (2) the effect of CGA, H 2 O 2 , and phenol injections on bacterial populations, (3) the stability and transport of CGAs over distance, and (4) CGA injection versus H 2 O 2 injection as an oxygenation technique

  8. Minimum Leakage Condenser Test Program

    International Nuclear Information System (INIS)

    1978-05-01

    This report presents the results and analysis of tests performed on four critical areas of large surface condensers: the tubes, tubesheets, tube/tubesheet joints and the water chambers. Significant changes in operation, service duty and the reliability considerations require that certain existing design criteria be verified and that improved design features be developed. The four critical areas were treated analytically and experimentally. The ANSYS finite element computer program was the basic analytical method and strain gages were used for obtaining experimental data. The results of test and analytical data are compared and recommendations made regarding potential improvement in condenser design features and analytical techniques

  9. Performance of evaporative condensers

    Energy Technology Data Exchange (ETDEWEB)

    Ettouney, Hisham M.; El-Dessouky, Hisham T.; Bouhamra, Walid; Al-Azmi, Bader

    2001-07-01

    Experimental investigation is conducted to study the performance of evaporative condensers/coolers. The analysis includes development of correlations for the external heat transfer coefficient and the system efficiency. The evaporative condenser includes two finned-tube heat exchangers. The system is designed to allow for operation of a single condenser, two condensers in parallel, and two condensers in series. The analysis is performed as a function of the water-to-air mass flow rate ratio (L/G) and the steam temperature. Also, comparison is made between the performance of the evaporative condenser and same device as an air-cooled condenser. Analysis of the collected data shows that the system efficiency increases at lower L/G ratios and higher steam temperatures. The system efficiency for various configurations for the evaporative condenser varies between 97% and 99%. Lower efficiencies are obtained for the air-cooled condenser, with values between 88% and 92%. The highest efficiency is found for the two condensers in series, followed by two condensers in parallel and then the single condenser. The parallel condenser configuration can handle a larger amount of inlet steam and can provide the required system efficiency and degree of subcooling. The correlation for the system efficiency gives a simple tool for preliminary system design. The correlation developed for the external heat transfer coefficient is found to be consistent with the available literature data. (Author)

  10. Modelling of film condensation in presence of non condensable gases

    International Nuclear Information System (INIS)

    Genevieve Geffraye; Dominique Bestion; Vladimir Kalitvianski

    2005-01-01

    Full text of publication follows: This paper presents recent developments in the modelling of the condensation due to heat removal from a wall with a possible presence of hydrogen, nitrogen, or air. This work is mainly concerned with nuclear reactor safety with particular reference to situations related to new reactor design, cold shutdown state and severe accident analysis. Film condensation of steam in presence of nitrogen and helium in a tube has been investigated in the COTURNE experiment in a rather large range of parameters, pressure (from 0.1 to 7 Mpa), heat flux (0.1 to 6 W/cm 2 ), mass fraction of noncondensable gas (0 to 1) and also in presence of superheated steam. The experiment represents a Steam Generator tube of a Pressurised Water Reactor and can simulate both co-current or countercurrent flow of steam and water.The models are implemented in the CATHARE code used for nuclear reactor thermal-hydraulics. The code uses two mass balance equations for liquid and gas, two momentum balance equations for liquid and gas and two energy balance equations for liquid and gas. Additional mass transport equations can be added for each non condensable gas. Heat transfers from wall to liquid film, from liquid to interface and gas to interface are modelled. The liquid film heat transfer coefficient is first investigated in pure saturated steam conditions in the pressure range from 0.1 to 7 Mpa. The CATHARE film condensation model in pure steam conditions is derived from Chen's correlation. Chen proposes a general correlation for the film condensation, covering the wavy-laminar and the turbulent film regimes and taking into account the interfacial friction effect. A large data base of laminar film regime was used including COTURNE data other available data found in the literature. The analysis of these data base suggests an influence of the liquid Reynolds number, according to the Nusselt theory, and also of the Eoetvoes number, with surface tension effects. A

  11. Irreversibility of Gas-Condensate Flow in Gas Cycling Projects: Kinetically Stable Saturation Patterns Irréversibilité des écoulements de gaz à condensat dans les projets de recyclage de gaz : profils stationnaires de saturation

    Directory of Open Access Journals (Sweden)

    Mitlin V.

    2006-12-01

    Full Text Available The dynamics of a two-phase multicomponent reservoir system which is approaching the steady-state flow regime are studied. First, the compositional model is analyzed in the linear approximation, for the case of a small initial deviation from the steady-state regime. An analytical expression is obtained for the characteristic relaxation time. Next, numerical simulations are performed for situations where there is a substantial deviation from the steady-state regime. The linear injection of an enriched gas into a gas-condensate reservoir, followed by the extraction regime, is simulated. It is shown that the change in phase compositions and pressure on the way to equilibrium proceeds with characteristic times of the order of the injection time. However, the change in the saturation and overall composition takes approximately 200 times longer than the injection time. Thus, the reservoir system manifests a spatially inhomogeneous saturation distribution for an abnormally long time. Similar kinetically stable patterns have been also discovered in the nonlinear dynamics of phase transitions, plasma, and thin films. The question of the existence of discontinuous steady states for this multicomponent flow is considered. In the case of a binary mixture, it is shown that such solutions do not exist. Cet article présente une étude de la dynamique d'un réservoir biphasique multiconstituant approchant le régime d'écoulement stationnaire. En premier lieu, nous procédons à une approximation linéaire du modèle compositionnel dans le cas des petites fluctuations autour du régime permanent. Une expression analytique est ainsi obtenue pour le temps caractéristique de transition. Des simulations numériques sont ensuite effectuées pour les déviations importantes par rapport au régime permanent. Nous avons ainsi pu étudier le déplacement linéaire d'un mélange gaz/condensat par un gaz enrichi suivi d'un régime de production. On montre alors que le

  12. A new technique in constructing closed-form solutions for nonlinear PDEs appearing in fluid mechanics and gas dynamics

    Directory of Open Access Journals (Sweden)

    Panayotounakos D. E.

    1996-01-01

    Full Text Available We develop a new unique technique in constructing closed-form solutions for several nonlinear partial differential systems appearing in fluid mechanics and gas dynamics. The obtained solutions include fewer arbitrary functions than needed for general solutions, fact that permits us to specify them according to the initial state, or the geometry, of each specific problem under consideration. In order to apply the before mentioned technique we construct closed-form solutions concerning the gas-dynamic equations with constant pressure, the dynamic equations of an ideal gas in isentropic flow, and the two-dimensional incompressible boundary layer flow.

  13. Gravitationally Driven Wicking for Enhanced Condensation Heat Transfer.

    Science.gov (United States)

    Preston, Daniel J; Wilke, Kyle L; Lu, Zhengmao; Cruz, Samuel S; Zhao, Yajing; Becerra, Laura L; Wang, Evelyn N

    2018-04-17

    Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Filmwise condensation is prevalent in typical industrial-scale systems, where the condensed fluid forms a thin liquid film due to the high surface energy associated with many industrial materials. Conversely, dropwise condensation, where the condensate forms discrete liquid droplets which grow, coalesce, and shed, results in an improvement in heat transfer performance of an order of magnitude compared to filmwise condensation. However, current state-of-the-art dropwise technology relies on functional hydrophobic coatings, for example, long chain fatty acids or polymers, which are often not robust and therefore undesirable in industrial conditions. In addition, low surface tension fluid condensates, such as hydrocarbons, pose a unique challenge because common hydrophobic condenser coatings used to shed water (with a surface tension of 73 mN/m) often do not repel fluids with lower surface tensions (condensation heat transfer using gravitationally driven flow through a porous metal wick, which takes advantage of the condensate's affinity to wet the surface and also eliminates the need for condensate-phobic coatings. The condensate-filled wick has a lower thermal resistance than the fluid film observed during filmwise condensation, resulting in an improved heat transfer coefficient of up to an order of magnitude and comparable to that observed during dropwise condensation. The improved heat transfer realized by this design presents the opportunity for significant energy savings in natural gas processing, thermal management, heating and cooling, and power generation.

  14. A galactic disk as a two-fluid system: Consequences for the critical stellar velocity dispersion and the formation of condensations in the gas

    International Nuclear Information System (INIS)

    Jog, C.J.; Solomon, P.M.

    1984-01-01

    We examine the consequences of treating a galactic disk as a two-fluid system for the stability of the entire disk and for the stability and form of the gas in the disk. We find that the existence of even a small fraction of the total disk surface density in a cold fluid (that is, the gas) makes it much harder to stabilize the entire two-fluid disk. (C/sub s/,min)/sub 2-f/, the critical stellar velocity dispersion for a two-fluid disk in an increasing function of μ/sub g//μ/sub s/, the gas fraction, and μ/sub t//kappa, where μ/sub g/, μ/sub s/, and μ/sub t/ are the gaseous, stellar, and total disk surface densities and kappa is the epicyclic frequency. In the Galaxy, we find that (C/sub s/,min)/sub 2-f/ as a function of R peaks when μ/sub t//kappa peaks-at galactocentric radii of Rapprox.5-7 kpc; two-fluid instabilities are most likely to occur in this region. This region is coincident with the peak in the molecular cloud distribution in the Galaxy. At the higher effective gas density resulting from the growth of a two-fluid instability, the gas may become unstble, even when originally the gas by itself is stable. The wavelength of a typical (induced) gas instability in the inner galaxy is approx.400 pc, and it contains approx.10 7 M/sub sun/ of interstellar matter; these instabilities may be identified with clusters of giant molecular clouds. We suggest that many of the spiral features seen in gas-rich spiral galaxies may be material arms or arm segments resulting from sheared two-fluid gravitational instabilities. The analysis presented here is applicable to any general disk galaxy consisting of stars and gas

  15. Advanced Laser-Based Techniques for Gas-Phase Diagnostics in Combustion and Aerospace Engineering.

    Science.gov (United States)

    Ehn, Andreas; Zhu, Jiajian; Li, Xuesong; Kiefer, Johannes

    2017-03-01

    Gaining information of species, temperature, and velocity distributions in turbulent combustion and high-speed reactive flows is challenging, particularly for conducting measurements without influencing the experimental object itself. The use of optical and spectroscopic techniques, and in particular laser-based diagnostics, has shown outstanding abilities for performing non-intrusive in situ diagnostics. The development of instrumentation, such as robust lasers with high pulse energy, ultra-short pulse duration, and high repetition rate along with digitized cameras exhibiting high sensitivity, large dynamic range, and frame rates on the order of MHz, has opened up for temporally and spatially resolved volumetric measurements of extreme dynamics and complexities. The aim of this article is to present selected important laser-based techniques for gas-phase diagnostics focusing on their applications in combustion and aerospace engineering. Applicable laser-based techniques for investigations of turbulent flows and combustion such as planar laser-induced fluorescence, Raman and Rayleigh scattering, coherent anti-Stokes Raman scattering, laser-induced grating scattering, particle image velocimetry, laser Doppler anemometry, and tomographic imaging are reviewed and described with some background physics. In addition, demands on instrumentation are further discussed to give insight in the possibilities that are offered by laser flow diagnostics.

  16. Evaluation of revegetation techniques of a saline flue gas desulfurization sludge pond

    Energy Technology Data Exchange (ETDEWEB)

    Salo, L.F.; Artiola, J.F.; Goodrich-Mahoney, J.W. [University of Arizona, Tucson, AZ (United States). Renewable National Resources

    1999-01-01

    Codisposal of flue gas desulfurization (FGD) sludge with low-volume generating station waste simplifies disposal but creates a saline, high boron (B) waste that may be difficult to revegetate after site closure. Studies on a delta of waste material in a codisposal pond at the coal-fired Coronado Generating Station in eastern Arizona evaluated management techniques, amendments, and plants for revegetating this material. One study investigated leaching and ridging techniques and a second evaluated amendment with manure, wood shavings, and fly ash, Four salt-tolerant grass species and four saltbushes (A triplex spp,) were evaluated in the two studies. Criteria for success were high survival rates and growth, as measured by grass height and shrub height x width. Leaching salts and B from the waste was not necessary for establishment and growth of transplanted shrubs and grasses. Ridging was not a successful technique, due to limited moisture and high levels of salinity and B on these structures. Gardner saltbush (A, gardneri (Moq.) D, Dietr.) and a fourwing saltbush (A. canescens (Pursh) Nutt,) accession from the site were the most successful shrubs and alkali sactonn (Sporobolus airoides (Torr,) Torr. `Saltalk`) was the most successful grass at this disposal pond. Amendment with manure, wood shavings, or fly ash did not increase plant survival. Growth of grasses was improved with all amendments and was greatest with manure, but growth of shrubs was not improved with any amendment. 33 refs., 8 tabs.

  17. Bose-Einstein Condensation

    International Nuclear Information System (INIS)

    Jaksch, D

    2003-01-01

    The Gross-Pitaevskii equation, named after one of the authors of the book, and its large number of applications for describing the properties of Bose-Einstein condensation (BEC) in trapped weakly interacting atomic gases, is the main topic of this book. In total the monograph comprises 18 chapters and is divided into two parts. Part I introduces the notion of BEC and superfluidity in general terms. The most important properties of the ideal and the weakly interacting Bose gas are described and the effects of nonuniformity due to an external potential at zero temperature are studied. The first part is then concluded with a summary of the properties of superfluid He. In Part II the authors describe the theoretical aspects of BEC in harmonically trapped weakly interacting atomic gases. A short and rather rudimentary chapter on collisions and trapping of atomic gases which seems to be included for completeness only is followed by a detailed analysis of the ground state, collective excitations, thermodynamics, and vortices as well as mixtures of BECs and the Josephson effect in BEC. Finally, the last three chapters deal with topics of more recent interest like BEC in optical lattices, low dimensional systems, and cold Fermi gases. The book is well written and in fact it provides numerous useful and important relations between the different properties of a BEC and covers most of the aspects of ultracold weakly interacting atomic gases from the point of view of condensed matter physics. The book contains a comprehensive introduction to BEC for physicists new to the field as well as a lot of detail and insight for those already familiar with this area. I therefore recommend it to everyone who is interested in BEC. Very clearly however, the intention of the book is not to provide prospects for applications of BEC in atomic physics, quantum optics or quantum state engineering and therefore the more practically oriented reader might sometimes wonder why exactly an equation is

  18. Thermodynamic entanglement of magnonic condensates

    Science.gov (United States)

    Yuan, H. Y.; Yung, Man-Hong

    2018-02-01

    Over the past decade, significant progress has been achieved to create Bose-Einstein condensates (BECs) of magnetic excitations, i.e., magnons, at room temperature, which is a novel quantum many-body system with a strong spin-spin correlation, and contains potential applications in magnonic spintronics. For quantum information science, the magnonic condensates can become an attractive source of quantum entanglement, which plays a central role in most of the quantum information processing tasks. Here we theoretically study the entanglement properties of a magnon gas above and below the condensation temperature. We show that the thermodynamic entanglement of the spins is a manifestation of the off-diagonal long-range order; the entanglement of the condensate does not vanish, even if the spins are separated by an infinitely long distance, which is fundamentally distinct from the normal magnetic ordering below the Curie temperature. In addition, the phase-transition point occurs when the derivative of the entanglement changes abruptly. These results provide a theoretical foundation for a future investigation of the magnon BEC in terms of quantum entanglement.

  19. Influence of Rain Tree Pod Meal Supplementation on Rice Straw Based Diets Using Gas Fermentation Technique

    Directory of Open Access Journals (Sweden)

    N. Anantasook

    2012-03-01

    Full Text Available The objective of this study was to determine the roughage to concentrate (R:C ratio with rain tree pod meal (RPM supplementation on in vitro fermentation using gas production technique. The experiment design was a 6×4 factorial arrangement in a CRD. Factor A was 6 levels of R:C ratio (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100 and factor B was 4 levels of RPM (0, 4, 8 and 12 mg. It was found that gas kinetic, extent rate (c was linearly increased (p<0.01 with an increasing level of concentrate while cumulative gas production (96 h was higher in R:C of 40:60. In addition, interaction of R:C ratio and RPM level affected NH3-N and IVDMD and were highest in R:C of 0:100 with 0, 4 mg of RPM and 40:60 with 8 mg of RPM, respectively. Moreover, interaction of R:C ratio and RPM level significantly increased total volatile fatty acids and propionate concentration whereas lower acetate, acetate to propionate ratios and CH4 production in R:C of 20:80 with 8 mg of RPM. Moreover, the two factors, R:C ratio and RPM level influenced the protozoal population and the percentage of methanogens in the total bacteria population. In addition, the use of real-time PCR found that a high level of concentrate in the diet remarkably decreased three cellulolytic bacteria numbers (F. succinogenes, R. flavefaciens and R. albus. Based on this study, it is suggested that the ratio of R:C at 40:60 and RPM level at 12 mg could improve ruminal fluid fermentation in terms of reducing fermentation losses, thus improving VFA profiles and ruminal ecology.

  20. Born-Kothari Condensation for Fermions

    Directory of Open Access Journals (Sweden)

    Arnab Ghosh

    2017-09-01

    Full Text Available In the spirit of Bose–Einstein condensation, we present a detailed account of the statistical description of the condensation phenomena for a Fermi–Dirac gas following the works of Born and Kothari. For bosons, while the condensed phase below a certain critical temperature, permits macroscopic occupation at the lowest energy single particle state, for fermions, due to Pauli exclusion principle, the condensed phase occurs only in the form of a single occupancy dense modes at the highest energy state. In spite of these rudimentary differences, our recent findings [Ghosh and Ray, 2017] identify the foregoing phenomenon as condensation-like coherence among fermions in an analogous way to Bose–Einstein condensate which is collectively described by a coherent matter wave. To reach the above conclusion, we employ the close relationship between the statistical methods of bosonic and fermionic fields pioneered by Cahill and Glauber. In addition to our previous results, we described in this mini-review that the highest momentum (energy for individual fermions, prerequisite for the condensation process, can be specified in terms of the natural length and energy scales of the problem. The existence of such condensed phases, which are of obvious significance in the context of elementary particles, have also been scrutinized.

  1. Characterization and modelling techniques for gas metal arc welding of DP 600 sheet steels

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, K.; Prahl, U.; Bleck, W. [RWTH Aachen University, Department of Ferrous Metallurgy (IEHK) (Germany); Reisgen, U.; Schleser, M.; Abdurakhmanov, A. [RWTH Aachen University, Welding and Joining Institute (ISF) (Germany)

    2010-11-15

    The objectives of the present work are to characterize the Gas Metal Arc Welding process of DP 600 sheet steel and to summarize the modelling techniques. The time-temperature evolution during the welding cycle was measured experimentally and modelled with the softwaretool SimWeld. To model the phase transformations during the welding cycle dilatometer tests were done to quantify the parameters for phase field modelling by MICRESS {sup registered}. The important input parameters are interface mobility, nucleation density, etc. A contribution was made to include austenite to bainite transformation in MICRESS {sup registered}. This is useful to predict the microstructure in the fast cooling segments. The phase transformation model is capable to predict the microstructure along the heating and cooling cycles of welding. Tensile tests have shown the evidence of failure at the heat affected zone, which has the ferrite-tempered martensite microstructure. (orig.)

  2. Use of adsorption and gas chromatographic techniques in estimating biodegradation of indigenous crude oils

    International Nuclear Information System (INIS)

    Kokub, D.; Allahi, A.; Shafeeq, M.; Khalid, Z.M.; Malik, K.A.; Hussain, A.

    1993-01-01

    Indigenous crude oils could be degraded and emulsified upto varying degree by locally isolated bacteria. Degradation and emulsification was found to be dependent upon the chemical composition of the crude oils. Tando Alum and Khashkheli crude oils were emulsified in 27 and 33 days of incubation respectively. While Joyamair crude oil and not emulsify even mainly due to high viscosity of this oil. Using adsorption chromatographic technique, oil from control (uninoculated) and bio degraded flasks was fractioned into the deasphaltened oil containing saturate, aromatic, NSO (nitrogen, sulphur, oxygen) containing hydrocarbons) and soluble asphaltenes. Saturate fractions from control and degraded oil were further analysed by gas liquid chromatography. From these analyses, it was observed that saturate fraction was preferentially utilized and the crude oils having greater contents of saturate fraction were better emulsified than those low in this fraction. Utilization of various fractions of crude oils was in the order saturate> aromatic> NSO. (author)

  3. Condensation of steam

    International Nuclear Information System (INIS)

    Prisyazhniuk, V.A.

    2002-01-01

    An equation for nucleation kinetics in steam condensation has been derived, the equation taking into account the concurrent and independent functioning of two nucleation mechanisms: the homogeneous one and the heterogeneous one. The equation is a most general-purpose one and includes all the previously known condensation models as special cases. It is shown how the equation can be used in analyzing the process of steam condensation in the condenser of an industrial steam-turbine plant, and in working out new ways of raising the efficiency of the condenser, as well as of the steam-turbine plant as a whole. (orig.)

  4. Low pressure lithium condensation

    International Nuclear Information System (INIS)

    Wadkins, R.P.; Oh, C.H.

    1985-01-01

    A low pressure experiment to evaluate the laminar film condensation coefficients of lithium was conducted. Some thirty-six different heat transfer tests were made at system pressures ranging from 1.3 to 26 Pa. Boiled lithium was condensed on the inside of a 7.6-cm (ID), 409 stainless-steel pipe. Condensed lithium was allowed to reflux back to the pool boiling region below the condensing section. Fourteen chromel/alumel thermocouples were attached in various regions of the condensing section. The thermocouples were initially calibrated with errors of less than one degree Celsius

  5. A novel acoustic method for gas flow measurement using correlation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Knuuttila, M. [VTT Chemical Technology, Espoo (Finland). Industrial Physics

    1997-12-31

    The study demonstrates a new kind of acoustic method for gas flow measurement. The method uses upstream and downstream propagating low frequency plane wave and correlation techniques for volume flow rate determination. The theory of propagating low frequency plane waves in the pipe is introduced and is proved empirically to be applicable for flow measurement. The flow profile dependence of the method is verified and found to be negligible at least in the region of moderate perturbations. The physical principles of the method were applied in practice in the form of a flowmeter with new design concepts. The developed prototype meters were verified against the reference standard of NMI (Nederlands Meetinstituut), which showed that a wide dynamic range of 1:80 is achievable with total expanded uncertainty below 0.3 %. Also the requirements used for turbine meters of linearity, weighted mean error and stability were shown to be well fulfilled. A brief comparison with other flowmeter types shows the new flowmeter to be competitive. The advantages it offers are a small pressure drop over the meter, no blockage of flow in possible malfunction, no pulsation to flow, essentially no moving parts, and the possibility for bidirectional measurements. The introduced flowmeter is also capable of using the telephone network or a radio-modem to read the consumption of gas and report its operation to the user. (orig.) 51 refs.

  6. Improving Gas Sensing Properties of Tin Oxide Nanowires Palladium-Coated Using a Low Cost Technique

    Directory of Open Access Journals (Sweden)

    M. Barzegar

    2012-12-01

    Full Text Available Thin films of SnO2 nanowires were successfully prepared by using chemical vapor deposition (CVD process on quartz substrates. Afterwards, a thin  layer of palladium (Pd as a catalyst was coated on top of nanowires. For the deposition of Pd, a simple and low cost technique of spray pyrolysis was employed, which caused an intensive enhancement on the sensing response of fabricated sensors. Prepared sensor devices were exposed to liquid petroleum gas (LPG and vapor of ethanol (C2H5OH. Results indicate that SnO2 nanowires sensors coated with Pd as a catalyst show decreasing in response time (~40s to 1000ppm of LPG at a relatively low operating temperature (200o C. SnO2 /Pd nanowire devices show gas sensing response time and recovery time as short as 50s and 10s respectively with a high sensitivity value of ~120 for C2H5OH, that is remarkable in comparison with other reports.

  7. Dynamics of capillary condensation in lattice gas models of confined fluids: a comparison of dynamic mean field theory with dynamic Monte Carlo simulations.

    Science.gov (United States)

    Edison, John R; Monson, Peter A

    2013-06-21

    This article addresses the accuracy of a dynamic mean field theory (DMFT) for fluids in porous materials [P. A. Monson, J. Chem. Phys. 128, 084701 (2008)]. The theory is used to study the relaxation processes of fluids in pores driven by step changes made to a bulk reservoir in contact with the pore. We compare the results of the DMFT to those obtained by averaging over large numbers of dynamic Monte Carlo (DMC) simulation trajectories. The problem chosen for comparison is capillary condensation in slit pores, driven by step changes in the chemical potential in the bulk reservoir and involving a nucleation process via the formation of a liquid bridge. The principal difference between the DMFT results and DMC is the replacement of a distribution of nucleation times and location along the pore for the formation of liquid bridges by a single time and location. DMFT is seen to yield an otherwise qualitatively accurate description of the dynamic behavior.

  8. Modelling of condensation phenomena

    International Nuclear Information System (INIS)

    Jeong, Jae Jun; Chang, Won Pyo

    1996-07-01

    Condensation occurs when vapor is cooled sufficiently below the saturation temperature to induce the nucleation of droplets. Such nucleation may occur homogeneously within the vapor or heterogeneously on entrained particular matter. Heterogeneous nucleation may occur on the walls of the system, where the temperature is below the saturation temperature. There are two forms of heterogeneous condensation, drop-wise and film-wise. Another form of condensation occurs when vapor directly contacts to subcooled liquid. In nuclear power plant systems, all forms of condensation may occur during normal operation or accident conditions. In this work the modelling of condensation is surveyed, including the Nusselts' laminar film condensation theory in 1916, Rohsenow's turbulent film condensation model in 1950s, and Chen's models in 1987. Major attention is paid on the film condensation models among various research results because of its importance in engineering applications. It is found that theory, experiment, and empirical correlations for film condensation are well established, but research for drop-wise and direct-contact condensation are not sufficient yet. Condensation models in the best-estimate system codes such as RELAP5/MOD3 and CATHARE2 are also investigated. 3 tabs., 11 figs., 36 refs. (Author)

  9. Applications of the automatic meter reading techniques at the Brazilian gas domestic market; Application des techniques de releve automatique des compteurs sur le marche domestique Bresilien du gaz

    Energy Technology Data Exchange (ETDEWEB)

    Venancio, J.; Monteiro, F. [Comgas, Sao Paulo (Brazil); D' Oliveira, R.D. [ORBIS, Curitiba (Brazil)

    2000-07-01

    This article will describe applications of the automation and automatic meter reading techniques at the internal gas pipes installations design, considering residential and commercial buildings, and taking in account the tendency of rapid growth of the activities related to the natural gas industry in Brazil, as well as the recently development of new technologies that can be applied with affordable prices. It will be analysed the application of an automatic meter reading technology in a building of several floors in Sao Paulo, which gas installations design is being carried up, with be purpose of making a comparative cost-effectiveness study with the traditional constructive methods applied in Brazil. As a result, it will be purposed a new commercialization model for the gas in Brazil at the residential and commercial market. (authors)

  10. Portable multi-sensor system for gas detection using the temporal window technique; Systeme multicapteurs de detection de gaz, portable, utilisant la technique du fenetrage temporel

    Energy Technology Data Exchange (ETDEWEB)

    Cazaubon, Ch. [Bordeaux-1 Univ., CRED, 33 - Talence (France); Levi, H.; Bordieu, Ch.; Rebiere, D.; Pistre, J. [Bordeaux-1 Univ., Lab. IXL, UMR CNRS 5818, 33 (France)

    1999-07-01

    An autonomous and portable multi-sensor system was constructed. It can drive four gas sensors (surface acoustic waves. SAW. for examples) and four voltage output gas sensors (semiconductor metal oxide sensors, for example). Two micro-controllers. MC68HC11F1 and MC68HC711E9, used as master and slave respectively, are mounted on two cards. The first card contains the signal processing treatment algorithm using a neural network and a shifting temporal window technique: it allows real time gas selection. The second card insure the overall temperature control by an auto-adaptive PID. GB gas SAW responses were applied to the device in order to test his performances. (authors)

  11. Condensate fluctuations of interacting Bose gases within a microcanonical ensemble.

    Science.gov (United States)

    Wang, Jianhui; He, Jizhou; Ma, Yongli

    2011-05-01

    Based on counting statistics and Bogoliubov theory, we present a recurrence relation for the microcanonical partition function for a weakly interacting Bose gas with a finite number of particles in a cubic box. According to this microcanonical partition function, we calculate numerically the distribution function, condensate fraction, and condensate fluctuations for a finite and isolated Bose-Einstein condensate. For ideal and weakly interacting Bose gases, we compare the condensate fluctuations with those in the canonical ensemble. The present approach yields an accurate account of the condensate fluctuations for temperatures close to the critical region. We emphasize that the interactions between excited atoms turn out to be important for moderate temperatures.

  12. Competition between Bose-Einstein Condensation and Spin Dynamics.

    Science.gov (United States)

    Naylor, B; Brewczyk, M; Gajda, M; Gorceix, O; Maréchal, E; Vernac, L; Laburthe-Tolra, B

    2016-10-28

    We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation by rapidly cooling a chromium multicomponent Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin-excited states. Small metastable spinor condensates are, nevertheless, produced, and they manifest in strong spin fluctuations.

  13. Characteristic aspects of pion-condensed phases

    International Nuclear Information System (INIS)

    Takatsuka, Tatsuyuki; Tamagaki, Ryozo; Tatsumi, Toshitaka.

    1993-01-01

    Characteristic aspects of pion-condensed phases are described in a simple model, for the system involving only nucleons and pions which interact through the π-N P-wave interaction. We consider one typical version in each of three kinds of pion condensation; the one of neutral pions (π 0 ), the one of charged pions (π C ) and the combined one in which both the π 0 and π C condensations are coexistent. Emphasis is put on the description to clarify the novel structures of the nucleon system which are realized in the pion-condensed phases. At first, it is shown that the π 0 condensation is equivalent to the particular nucleonic phase realized by a structure change of the nucleon system, where the attractive first-order effect of the one-pion-exchange (OPE) tensor force is brought about coherently. The aspects of this phase are characterized by the layered structure with a specific spin-isospin order with one-dimensional localization (named the ALS structure in short), which provides the source function for the condensed π 0 field. We utilize both descriptions with use of fields and potentials for the π 0 condensation. Next, the π C condensation realized in neutron-rich matter is described by adopting a version of the traveling condensed wave. In this phase, the nucleonic structure becomes the Fermi gas consisting of quasi-neutrons described by a superposition of neutron and proton. In this sense the structure change of the nucleon system for the π C condensation is moderate, and the field description is suitable. Finally, we describe a coexistent pion condensation, in which both the π 0 and π C condensations coexist without interference in such a manner that the π C condensation develops in the ALS structure. The model adopted here provides us with the characteristic aspects of the pion-condensed phases persisting in the realistic situation, where other ingredients affecting the pion condensation are taken into account. (author)

  14. In vitro cumulative gas production techniques: history, methodological considerations and challenges

    NARCIS (Netherlands)

    Rymer, C.; Huntington, J.A.; Williams, B.A.; Givens, D.I.

    2005-01-01

    Methodology used to measure in vitro gas production is reviewed to determine impacts of sources of variation on resultant gas production profiles (GPP). Current methods include measurement of gas production at constant pressure (e.g., use of gas tight syringes), a system that is inexpensive, but may

  15. Experience of molecular monitoring techniques in upstream oil and gas operations

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Anthony F.; Anfindsen, Hilde; Liengen, Turid; Molid, Solfrid [Statoil ASA (Denmark)

    2011-07-01

    For a numbers of years, molecular monitoring tools have been used in upstream oil and gas operations but the results have given only limited added value. This paper discusses the various techniques available for upstream molecular monitoring which provides scope for identification of microbial influenced problems. The methodology, which consists of analyzing solid samples using traditional as well as molecular techniques, is detailed. Two cases were studied with the objective of determining if microbial contamination was contributing to the problem. The first case was a study of amorphous deposits in production wells and mainly iron sulphide was found. The second study was of amorphous deposits in water injection wells and the analysis showed typical components of drilling and completion fluids with some organic material. Two more cases, corrosion of tubing in a water injection well and flow line corrosion, are discussed and the results are given. From the study, it can be concluded that failure can be due to several factors, chemical and biological.

  16. Bose-Einstein condensates in atomic gases: simple theoretical results

    International Nuclear Information System (INIS)

    Castin, Y.

    2001-01-01

    The author presents the theory of the Bose-Einstein condensation along with a discussion of experimental tests. The author deals successively with the following topics: - the ideal Bose gas in a trap (first in a harmonic trap and then in a more general trap), - a model for the atomic interaction, - interacting Bose gas in the Hartree-Fock approximation, - properties of the condensate wavefunction, - the Gross-Pitaevskii equation, - Bogoliubov approach and thermodynamical stability, - phase coherence properties at the Bose-Einstein condensate, and - symmetry-breaking description of condensates. (A.C.)

  17. Dynamics and Evolution of SO 2 Gas Condensation around Prometheus-like Volcanic Plumes on Io as Seen by the Near Infrared Mapping Spectrometer

    Science.gov (United States)

    Douté, Sylvain; Lopes, Rosaly; Kamp, Lucas W.; Carlson, Robert; Schmitt, Bernard; Galileo NIMS Team

    2002-08-01

    We analyze a series of spectral image cubes acquired by the Galileo Near Infrared Mapping Spectrometer (NIMS) over the Prometheus region of Io. We use SO 2 frost, a volatile compound ubiquitous on the surface, as a tracer to understand various thermodynamic and volcanic processes acting in this equatorial region. Here we develop a new method to derive, from the 12-wavelength NIMS products, the distribution and physical properties of solid SO 2. This method is based on the inversion of a bidirectional reflectance model on two observed spectral ratios sensitive to (1) the areal abundance of SO 2 and (2) its mean grain size. As a result, reliable and consistent maps of SO 2 abundance and granularity are obtained which can be correlated to distinguish four different physical units. The distribution of these SO 2 units indicates zones of condensation, metamorphism, and sublimation linked with the thermodynamic and volcanic processes of interest. Our maps depict equatorial plains undisturbed by any kind of vigorous volcanic activity over 35-40% of their surface. Elsewhere, 10-20% of the equatorial plains display abnormally low frost coverage which may imply the recent presence of positive thermal anomalies with temperatures in the range 110-200 K. Hot-spots such as Prometheus, Culann, Surya, and Tupan (to mention the most persistent) emit a great variety of gases, some of which will condense at Io's surface near their source regions. Associated fields of freshly condensed SO 2 are easily observed, and deposits of more refractory compounds with higher (e.g., S 8) or lower (e.g., NaCl) molecular weight must also be present (although their exact nature is unknown). Three different mechanisms of emission are proposed for the volatile compounds and supported by the distribution maps. These are (a) the interaction between flowing lava and preexisting volatile deposits on the surface, (b) direct degassing from the lava, an d (c) the eruption of a liquid aquifer from underground

  18. Condensing boiler applications in the process industry

    International Nuclear Information System (INIS)

    Chen, Qun; Finney, Karen; Li, Hanning; Zhang, Xiaohui; Zhou, Jue; Sharifi, Vida; Swithenbank, Jim

    2012-01-01

    Major challenging issues such as climate change, energy prices and fuel security have focussed the attention of process industries on their energy efficiency and opportunities for improvement. The main objective of this research study was to investigate technologies needed to exploit the large amount of low grade heat available from a flue gas condensing system through industrial condensing boilers. The technology and application of industrial condensing boilers in various heating systems were extensively reviewed. As the condensers require site-specific engineering design, a case study was carried out to investigate the feasibility (technically and economically) of applying condensing boilers in a large scale district heating system (40 MW). The study showed that by recovering the latent heat of water vapour in the flue gas through condensing boilers, the whole heating system could achieve significantly higher efficiency levels than conventional boilers. In addition to waste heat recovery, condensing boilers can also be optimised for emission abatement, especially for particle removal. Two technical barriers for the condensing boiler application are corrosion and return water temperatures. Highly corrosion-resistant material is required for condensing boiler manufacture. The thermal design of a 'case study' single pass shell-and-tube condensing heat exchanger/condenser showed that a considerable amount of thermal resistance was on the shell-side. Based on the case study calculations, approximately 4900 m 2 of total heat transfer area was required, if stainless steel was used as a construction material. If the heat transfer area was made of carbon steel, then polypropylene could be used as the corrosion-resistant coating material outside the tubes. The addition of polypropylene coating increased the tube wall thermal resistance, hence the required heat transfer area was approximately 5800 m 2 . Net Present Value (NPV) calculations showed that the choice of a carbon

  19. Managing landfill gas. Techniques and recommendations. To know in order to act - Guides and Technical Guidebook

    International Nuclear Information System (INIS)

    Couturier, Christian; Meiffren, Isabelle; Dumas, Bruno; Galtier, Laurent; Prud'homme, Eric; Hebe, Isabelle; Riquier, Laurent; Miralves, James; Riviere, Georges; Herault, Irene

    2001-12-01

    This guide first recalls some basic notions about landfill gas: presence of three gases in varying proportions (biogas, air, and volatile compounds), biogas composition, toxicity and explosiveness of the various landfill gas components, production mechanism and evolution in time of landfill gas composition. The next part proposes a large and discussed overview of the different objectives of landfill gas management: reduction of environmental impacts, safety and security of people and assets, compliance with regulatory requirements, to provide better conditions for biogas valorisation, long term performance of gas management. Different types of tools and methods are discussed for the study of landfill biogas management and production: calculations, measurements, controls and audits. The design and implementation of gas management systems is then addressed: equipment securing, general procedures, gas capturing, gas collection, gas processing and conditioning, analysis, measurement and control. The next part addresses issues related to exploitation: safety, maintenance organisation, control and command

  20. Determining of Degradation and Digestion Coefficients of Canola meal Using of In situ and Gas production Techniques

    Directory of Open Access Journals (Sweden)

    Younes Tahmazi

    2015-04-01

    Full Text Available This study was carried out to the determination of nutritive value of canola meal using naylon bag and cumulative gas production techniques in Gizel sheep. Tow fistulated Gizel sheep with average BW 45±2 kg used in a complete randomized design. The cumulative gas production was measured at 2, 4, 6, 8, 12, 16, 24, 36 and 48 h and ruminal DM and CP disappearance were measured up to 96 h. Coefficients of soluble CP degradation of canola meal (A, canola meal treated with 0.5% urea (B and canola meal treated with micro wave (C were 4.74, 15.81 and 15%, and for fermentable portion were 31.05, 39.62 and 65.55%, respectively. The cumulative gas production of soluble and insoluble portions (a+b were 252.13, 213.57 and 240.88 ml/g DM. Metabolizable protein of treatments A, B and C were 283.11, 329.33 and 284.39 g/kg DM, that were not significantly different. The relationship between dry matter and cumulative gas production values for treatments obtained about 0.958, 0.976 and 0.932 and this parameter for crude protein and cumulative gas production achieved 0.987, 0.994 and 0.989, respectively. High correlation between in situ and cumulative gas production techniques indicated that digestibility values can be predicted from cumulative gas production data.

  1. Ionizing radiation effects in Acai oil analysed by gas chromatography coupled to mass spectrometry technique

    International Nuclear Information System (INIS)

    Valli, Felipe; Fernandes, Carlos Eduardo; Moura, Sergio; Machado, Ana Carolina; Furasawa, Helio Akira; Pires, Maria Aparecida Faustino; Bustillos, Oscar Vega

    2007-01-01

    The Acai fruit is a well know Brazilian seed plant used in large scale as a source of feed stock, specially in the Brazilian North-east region. The Acai oil is use in many purposes from fuel sources to medicine. The scope of this paper is to analyzed the chemical structures modification of the acai oil after the ionizing radiation. The radiation were set in the range of 10 to 25 kGy in the extracted Acai oil. The analyses were made by gas chromatography coupled to mass spectrometry techniques. A GC/MS Shimatzu QP-5000 equipped with 30 meters DB-5 capillary column with internal diameter of 0.25 mm and 0.25 μm film thickness was used. Helium was used as carried gas and gave a column head pressure of 12 p.s.i. (1 p.s.i. = 6894.76 Pa) and an average flux of 1 ml/min. The temperature program for the GC column consisted of a 4-minutes hold at 75 deg C, a 15 deg C /min ramp to 200 deg C, 8 minutes isothermal. 20 deg C/min ramp to 250 deg C, 2 minutes isothermal. The extraction of the fatty acids was based on liquid-liquid method using chloroform as solvent. The chromatograms resulted shows the presences of the oleic acid and others fatty acids identify by the mass spectra library (NIST-92). The ionization radiation deplete the fatty acids presents in the Acai oil. Details on the chemical qualitative analytical is present as well in this work. (author)

  2. Study of condensate removal from wells

    Energy Technology Data Exchange (ETDEWEB)

    Gusein-Zade, Z I

    1967-01-01

    A pressure profile of well No. 218 in the Karadag condensate field showed that pressure did not vary linearly with depth. Calculations indicated that at depths of 3,000-3,640 m, produced fluid had a density of 0.29g/ cmU3D, whereas pure condensate gas should have a density of 0.11g/cmU3D. Apparently liquid was accumulating in the well. Other data showed that gas velocity in the well at various depths varied from 6 to 11 m/sec. It was also found that this same range of gas velocities was sufficient to prevent liquid accumulation in other wells. In an effort to solve this problem, the upward flow of gas-water and of gas-condensate mixtures in tubes was studied. Each had a different flow regime. Gas-condsensate formed foam, whereas the gas-water mixture did not. This resolved the problem, since foam is known to aid the removal of liquid by gas. Additional research showed that water was present in, and promoted accumulation of, liquid in well No. 218.

  3. Condensate cleaning systems

    International Nuclear Information System (INIS)

    Yamamoto, Michiyoshi; Oosumi, Katsumi; Takashima, Yoshie; Mitani, Shinji.

    1982-01-01

    Purpose: To decrease the frequency for the backwash and regeneration operations due to the increase in the differential pressure resulted from claddings captured in a mixed floor type desalter, and decrease the amount of radioactive liquid wastes of claddings from the condensate systems by removing claddings with electromagnetic filters. Constitution: In an existent plant, a valves is disposed between a condensate pump and a mixed floor type desalter. A pipeway is branched from a condensate pipe between the condensate pipe and the valve, through which condensates are transferred by a pump to an electromagnetic filter such as of a high gradient type electromagntic filter to remove claddings, then returned to a condensate pipe between the valve and the mixed floor type desalter and, thereafter, are removed with ionic components in the mixed floor type desalter and fed to the reactor. (Yoshino, Y.)

  4. Purification method for condensate

    International Nuclear Information System (INIS)

    Shimoda, Akiyoshi.

    1996-01-01

    Condensates generated in secondary coolant circuits of a PWR type reactor are filtered using a hollow thread separation membranes comprising aromatic polyether ketone. Preferably, condensates after passing through a turbine are filtered at a place between a condensator and a steam generator at high temperature as close as a temperature of the steam generator. As the hollow thread membrane, partially crystalline membrane comprising aromatic polyether ketone is used. When it is used at high temperature, the crystallinity is preferably not less than 15wt%. Since a hollow thread membrane comprising the aromatic polyether ketone of excellent heat resistance is used, it can filter and purify the condensates at not lower than 70degC. Accordingly, impurities such as colloidal iron can be removed from the condensates, and the precipitation of cruds in the condensates to a steam generator and a turbine can be suppressed. (I.N.)

  5. On the prediction of condenser plate temperatures in a cross-flow condenser

    NARCIS (Netherlands)

    Ganzevles, F.L.A.; Geld, van der C.W.M.

    2002-01-01

    A prediction method is presented for the gas-sided plate temperatures at the inlet and at the outlet of a compact, cross-flow condenser. The method employs measured (or predicted) heat flow rates and temperatures of both coolant and gas, at inlet and outlet. The method is validated using infrared

  6. Emergency condensator for BWR type reactor

    International Nuclear Information System (INIS)

    Ubakai, Yoichi; Narumi, Yuichi; Sakata, Yuji.

    1992-01-01

    An emergency condensator is constituted with heat transfer pipes, a steam chamber, an upper pipe plate, a lower pipe plate and a condensate chamber. The upper pipe plate is secured by supports, and a steam pipe is connected to the upper pipe plate. A condensate pipeline and a incondensible gas vent pipe are disposed to the condensate chamber. Taking thermal expansion of the steam pipes and thermal expansion of the heat transfer pipes into consideration, the heat transfer pipe is made as an L-shaped pipe having a vertical portion and a horizontal portion so as to absorb each of the thermal expansion smoothly. The L-shaped heat transfer pipes are constituted as a bundle of pipes having the end portions thereof secured to the upper pipe plate and the lower pipe plate. The emergency condensator is disposed in a emergency condensator pool chamber. Cooling water in contact with the outer side of the L-shaped heat transfer pipes is the pool water in the pool chamber, and the condensator chamber is disposed in concrete walls of the pool chamber. With such a constitution, stress due to thermal expansion of the heat transfer pipes is mitigated, and heat transfer performance, earth quake resistance and maintenancability are improved. (I.N.)

  7. Gas-phase spectroscopic studies of heavy elements compounds (group V) using FTIR technique

    International Nuclear Information System (INIS)

    Allaf, A. W.; Ajji, Z.

    1998-12-01

    Antimony oxide trihalide, OSbX3 where X=F, CI and Br, and antimony (III) oxychloride, OSbC1 molecules were produced by an on-line process for the first time using antimony chloride SbC13 passed over heated silver oxide then followed by passing the obtained products over heated NaF and heated KBr for SbOF3 and OSbBr3, respectively. The obtained OSbC13 reacts with heated silver to produce OSbC1. The products have been characterized by the infrared spectra of their vapors. The low resolution gas-phase Fourier transform infrared spectrum, reported for the first time, shows the most characteristic band of OSbX3 at 1272, 1217 and 1200 cm -1 and the bands are assigned to the O=Sb stretching fundamental of OSbX3 were X=F, Cl and Br, respectively. The band at 1200 cm -1 needs more experimental investigation. The band at 924 cm -1 is assigned to the O=Sb stretching fundamental of OSbCl molecule. This result is in consistent with expectation and shifted to lower frequency in comparison with arsenic analogous molecule which is investigated by matrix-isolation technique. The work will be continued in order to cover the bismuth and arsenic compounds of similar structures. (author)

  8. Gas-phase spectroscopy of synephrine by laser desorption supersonic jet technique.

    Science.gov (United States)

    Ishiuchi, Shun-ichi; Asakawa, Toshiro; Mitsuda, Haruhiko; Miyazaki, Mitsuhiko; Chakraborty, Shamik; Fujii, Masaaki

    2011-09-22

    In our previous work, we found that synephrine has six conformers in the gas phase, while adrenaline, which is a catecholamine and has the same side chain as synephrine, has been reported to have only two conformers. To determine the conformational geometries of synephrine, we measured resonance enhanced multiphoton ionization, ultraviolet-ultraviolet hole burning, and infrared dip spectra by utilizing the laser desorption supersonic jet technique. By comparing the observed infrared spectra with theoretical ones, we assigned geometries except for the orientations of the phenolic OH group. Comparison between the determined structures of synephrine and those of 2-methylaminno-1-phenylethanol, which has the same side chain as synephrine but no phenol OH group, leads to the conclusion that the phenolic OH group in synephrine does not affect the conformational flexibility of the side chain. In the case of adrenaline, which is expected to have 12 conformers if there are no interactions between the catecholic OH groups and the side chain, some interactions possibly exist between them because only two conformations are observed. By estimation of the dipole-dipole interaction energy between partial dipole moments of the catecholic OH groups and the side chain, it was concluded that the dipole-dipole interaction stabilizes specific conformers which are actually observed. © 2011 American Chemical Society

  9. Measuring gas-residence times in large municipal incinerators, by means of a pseudo-random binary signal tracer technique

    International Nuclear Information System (INIS)

    Nasserzadeh, V.; Swithenbank, J.; Jones, B.

    1995-01-01

    The problem of measuring gas-residence time in large incinerators was studied by the pseudo-random binary sequence (PRBS) stimulus tracer response technique at the Sheffield municipal solid-waste incinerator (35 MW plant). The steady-state system was disturbed by the superimposition of small fluctuations in the form of a pseudo-random binary sequence of methane pulses, and the response of the incinerator was determined from the CO 2 concentration in flue gases at the boiler exit, measured with a specially developed optical gas analyser with a high-frequency response. For data acquisition, an on-line PC computer was used together with the LAB Windows software system; the output response was then cross-correlated with the perturbation signal to give the impulse response of the incinerator. There was very good agreement between the gas-residence time for the Sheffield MSW incinerator as calculated by computational fluid dynamics (FLUENT Model) and gas-residence time at the plant as measured by the PRBS tracer technique. The results obtained from this research programme clearly demonstrate that the PRBS stimulus tracer response technique can be successfully and economically used to measure gas-residence times in large incinerator plants. It also suggests that the common commercial practice of characterising the incinerator operation by a single-residence-time parameter may lead to a misrepresentation of the complexities involved in describing the operation of the incineration system. (author)

  10. Gas-phase thermal dissociation of uranium hexafluoride: Investigation by the technique of laser-powered homogeneous pyrolysis

    International Nuclear Information System (INIS)

    Bostick, W.D.; McCulla, W.H.; Trowbridge, L.D.

    1987-04-01

    In the gas-phase, uranium hexafluoride decomposes thermally in a quasi-unimolecular reaction to yield uranium pentafluoride and atomic fluorine. We have investigated this reaction using the relatively new technique of laser-powered homogeneous pyrolysis, in which a megawatt infrared laser is used to generate short pulses of high gas temperatures under strictly homogeneous conditions. In our investigation, SiF 4 is used as the sensitizer to absorb energy from a pulsed CO 2 laser and to transfer this energy by collisions with the reactant gas. Ethyl chloride is used as an external standard ''thermometer'' gas to permit estimation of the unimolecular reaction rate constants by a relative rate approach. When UF 6 is the reactant, CF 3 Cl is used as reagent to trap atomic fluorine reaction product, forming CF 4 as a stable indicator which is easily detected by infrared spectroscopy. Using these techniques, we estimate the UF 6 unimolecular reaction rate constant near the high-pressure limit. In the Appendix, we describe a computer program, written for the IBM PC, which predicts unimolecular rate constants based on the Rice-Ramsperger-Kassel theory. Parameterization of the theoretical model is discussed, and recommendations are made for ''appropriate'' input parameters for use in predicting the gas-phase unimolecular reaction rate for UF 6 as a function of temperature and gas composition and total pressure. 85 refs., 17 figs., 14 tabs

  11. Studies of some elementary processes involving electrons in the gas phase by pulse-radiolysis microwave-cavity technique

    International Nuclear Information System (INIS)

    Sunagawa, Takeyoshi; Makita, Takeshi; Musasa, Hirofumi; Tatsumi, Yoshitsugu; Shimamori, Hiroshi

    1995-01-01

    The pulse radiolysis-microwave cavity technique has been employed for detection of free electrons in the gas phase. Presented are results of the observation of electron disappearance by attachment to molecules, the electron thermalization (energy loss) processes in the presence of an electron-attaching compound, and the formation of electrons by Penning ionization. (author)

  12. Portable optical frequency standard based on sealed gas-filled hollow-core fiber using a novel encapsulation technique

    DEFF Research Database (Denmark)

    Triches, Marco; Brusch, Anders; Hald, Jan

    2015-01-01

    A portable stand-alone optical frequency standard based on a gas-filled hollow-core photonic crystal fiber is developed to stabilize a fiber laser to the 13C2H2 P(16) (ν1 + ν3) transition at 1542 nm using saturated absorption. A novel encapsulation technique is developed to permanently seal...

  13. Visualization of cross-sectional flow structure during condensation of steam in a slightly inclined horizontal tube

    Energy Technology Data Exchange (ETDEWEB)

    Puseya, Andree; Kim, H. [Kyung Hee University, Yongin (Korea, Republic of); Kwon, T. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    These flow characteristics called flow patterns still depend on a proper visualization technique in order to identify such local distribution. These proper distributions will have a dependence on the inclination of the tube as well, as it was demonstrated by Lips and Mayer. This work is focused on presenting an experimental investigation to visualize the cross sectional two-phase flow structure for condensation of steam in a horizontal tube and identify the liquid-gas interface using the axial-viewing technique. This innovative technique developed by Hewitt and more recently used in visualization works by Badie, permits the achievement to identify those systems in the area of interest by looking directly into the two-phase flow system during condensation of steam inside a pipe with technology such a high speed camera. An experimental work to visualize and locate the liquid-gas interface for steam condensation in horizontal tubes with slightly inclination was developed on this research The experimental results shows that the axial viewing technique works well with condensation phenomena and can be used for further developments in the field such as determination of liquid film geometry and calculation of void fraction.

  14. Condensation During Nuclear Reactor Loca

    International Nuclear Information System (INIS)

    Rihan, Y.; Teamah, M.; Sorour, M.; Soliman, S.

    2008-01-01

    Two-phase channel flow with condensation is a common phenomenon occurs in a number of nuclear reactor accident scenarios. It also plays an important role during the operation of the safety coolant injection systems in advanced nuclear reactors. Semiempirical correlations and simple models based on the analogy between heat and mass transfer processes have been previously applied. Rigorous models, compatible with the state-of-the-art numerical algorithms used in thermal-hydraulic computer codes, are scare, and are of great interest. The objective of this research is to develop a method for modeling condensation, with noncondensable gases, compatible with the state-of-the-art numerical methods for the solution of multi-phase field equations. A methodology for modeling condensation, based on the stagnant film theory, and compatible with the reviewed numerical algorithms, is developed. The model treats the coupling between the heat and mass transfer processes, and allows for an implicit treatment of the mass and momentum exchange terms as the gas-liquid interphase, without iterations. The developed model was used in the application of loss of coolant in pressurized water reactor accidents

  15. Systematic text condensation

    DEFF Research Database (Denmark)

    Malterud, Kirsti

    2012-01-01

    To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies.......To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies....

  16. Condensation in complex geometries

    International Nuclear Information System (INIS)

    Lauro, F.

    1975-01-01

    A mathematical evaluation of the condensation exchange coefficient can only succeds for well specified cases: small upright or inclined plates, horizontal tubes, small height vertical tubes. Among the main hypotheses accounted for this mathematical development in the case of the condensate, a laminar flow and uniform surface temperature are always considered. In practice certain shapes of surfaces significantly increase the heat transfer during the vapor condensation on a surface wet by the condensate. Such surfaces are rough surfaces such as the condensate is submitted to surface tension effects, negligeable for plane or large curvature surfaces, and the nature of the material may play an important role (temperature gradients). Results from tests on tubes with special shapes, performed in France or out of France, are given [fr

  17. Fundamentals of condensed matter physics

    CERN Document Server

    Cohen, Marvin L

    2016-01-01

    Based on an established course and covering the fundamentals, central areas, and contemporary topics of this diverse field, Fundamentals of Condensed Matter Physics is a much-needed textbook for graduate students. The book begins with an introduction to the modern conceptual models of a solid from the points of view of interacting atoms and elementary excitations. It then provides students with a thorough grounding in electronic structure as a starting point to understand many properties of condensed matter systems - electronic, structural, vibrational, thermal, optical, transport, magnetic and superconductivity - and methods to calculate them. Taking readers through the concepts and techniques, the text gives both theoretically and experimentally inclined students the knowledge needed for research and teaching careers in this field. It features 200 illustrations, 40 worked examples and 150 homework problems for students to test their understanding. Solutions to the problems for instructors are available at w...

  18. Avalanches in a Bose-Einstein condensate

    NARCIS (Netherlands)

    Schuster, J.; Marte, A.; Amtage, S.; Sang, B.; Rempe, G.; Beijerinck, H.C.W.

    2001-01-01

    Collisional avalanches are identified to be responsible for an 8-fold increase of the initial loss rate of a large 87Rb condensate. We show that the collisional opacity of an ultracold gas exhibits a critical value. When exceeded, losses due to inelastic collisions are substantially enhanced. Under

  19. Coherent decay of positronium bose condensate

    International Nuclear Information System (INIS)

    Vanyashin, V.S.

    1992-07-01

    The rate of self-stimulated emission of photon pairs by pseudoscalar particles from Bose condensate is calculated. Growing with density this rate exceeds the density independent rate of spontaneous two photon decay at plausible density values of positronium gas, thus opening in principle, the way to the annihilation gamma ray laser realization. (author). 2 refs

  20. A radiotracer technique for testing a high pressure gas compressor for oil leakage

    International Nuclear Information System (INIS)

    Eapen, A.C.; Kirti; Jain, S.K.; Gupta, P.P.

    1979-01-01

    The radiotracer investigations carried out at NOCIL, Bombay, to measure the amount of lubrication oil present in the gas being compressed in a 1000 H.P. centrifugal compressor are described. By injecting a few mCi 131 I labelled glyceryl trioleate tracer and monitoring the radioactivity of the outlet gas for about 20 hours, the extent of the oil present in the gas could be determined. (auth.)

  1. Capillary condensation in porous alumina observed by positronium lifetime spectroscopy

    International Nuclear Information System (INIS)

    Ivanov, Eugeniu; Vata, Ion; Toderian, Stefan; Dudu, Dorin; Rusen, Ion; Stefan, Nitisor

    2008-01-01

    The PALS method based on time distribution measurements has been used to study capillary condensation of different gases adsorbed in microporous alumina powder. The isotherms exhibit features which are associated with a shifted gas-liquid transition. The sorption and desorption processes are irreversible presenting a hysteresis effect. Suggestions on some new aspects of the capillary condensation dynamics are made

  2. Coexistence of hyperon and π condensation in neutron stars

    International Nuclear Information System (INIS)

    Isshiki, Akinori

    2000-01-01

    We consider the coexistence of hyperon and π condensation in neutron stars. The coexistence phase may occur because of the strong ΛΣπ coupling. Hyperon can appear under π condensation, because short range repulsion reduce the π-baryon p wave attraction. The system approaches the Fermi gas because of this reduction. (author)

  3. Atmospheric Transmission Measurements Using IR Lasers, Fourier Transform Spectroscopy, and Gas-Filter Correlation Techniques

    National Research Council Canada - National Science Library

    Dowling, J

    1977-01-01

    ... and a gas filter correlation spectrometer. Results obtained from three concurrent experiments used to generate a data base appropriate to high resolution transmission model validation are displayed...

  4. Chemometric profile of root extracts of Rhodiola imbricata Edgew. with hyphenated gas chromatography mass spectrometric technique.

    Directory of Open Access Journals (Sweden)

    Amol B Tayade

    Full Text Available Rhodiola imbricata Edgew. (Rose root or Arctic root or Golden root or Shrolo, belonging to the family Crassulaceae, is an important food crop and medicinal plant in the Indian trans-Himalayan cold desert. Chemometric profile of the n-hexane, chloroform, dichloroethane, ethyl acetate, methanol, and 60% ethanol root extracts of R. imbricata were performed by hyphenated gas chromatography mass spectrometry (GC/MS technique. GC/MS analysis was carried out using Thermo Finnigan PolarisQ Ion Trap GC/MS MS system comprising of an AS2000 liquid autosampler. Interpretation on mass spectrum of GC/MS was done using the NIST/EPA/NIH Mass Spectral Database, with NIST MS search program v.2.0g. Chemometric profile of root extracts revealed the presence of 63 phyto-chemotypes, among them, 1-pentacosanol; stigmast-5-en-3-ol, (3β,24S; 1-teracosanol; 1-henteracontanol; 17-pentatriacontene; 13-tetradecen-1-ol acetate; methyl tri-butyl ammonium chloride; bis(2-ethylhexyl phthalate; 7,8-dimethylbenzocyclooctene; ethyl linoleate; 3-methoxy-5-methylphenol; hexadecanoic acid; camphor; 1,3-dimethoxybenzene; thujone; 1,3-benzenediol, 5-pentadecyl; benzenemethanol, 3-hydroxy, 5-methoxy; cholest-4-ene-3,6-dione; dodecanoic acid, 3-hydroxy; octadecane, 1-chloro; ethanone, 1-(4-hydroxyphenyl; α-tocopherol; ascaridole; campesterol; 1-dotriacontane; heptadecane, 9-hexyl were found to be present in major amount. Eventually, in the present study we have found phytosterols, terpenoids, fatty acids, fatty acid esters, alkyl halides, phenols, alcohols, ethers, alkanes, and alkenes as the major group of phyto-chemotypes in the different root extracts of R. imbricata. All these compounds identified by GC/MS analysis were further investigated for their biological activities and it was found that they possess a diverse range of positive pharmacological actions. In future, isolation of individual phyto-chemotypes and subjecting them to biological activity will definitely prove fruitful

  5. Comparative evaluation of a two stroke compressed natural gas mixer design using simulation and experimental techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ramasamy, D.; Bakar, R.A.; Rahim, M.F.; Noor, M.M. [Malaysia Pahang Univ., Pahang (Malaysia). Automotive Focus Group

    2008-07-01

    A study was conducted in which a two-stroke engine was converted for use with bi-fuel, notably compressed natural gas and gasoline. The excessive by-products generated by two-stroke engine combustion can be attributed to the inefficient combustion process. This prototype uniflow-type single-cylinder engine was equipped with a bi-fuel conversion system. A dedicated mixer was also developed to meter the gaseous fuel through the engine intake system. It was designed to meet air and fuel requirement similar to its gasoline counterpart. The mixer was modeled to obtain optimum orifice diameter using three different sizes of 14, 16 and 18 mm respectively. A standard computational fluid dynamics (CFD) software package was used to simulate the flow. A pressure reading was obtained during the prototype test. The drop in pressure across the venturi was shown to be an important parameter as it determined the actual fuel-air ratio in the actual engine. A good agreement of CFD outputs with that of the experimental outputs was recorded. The experimental technique validated the pressure distribution predicted by CFD means on the effects of the three insert rings in the CNG mixer. The simulation exercise can be used to predict the amount of CNG consumed by the engine. It was concluded that the 14 mm throat ring was best suited for the CNG mixer because it provided the best suction. Once the mixer is tested on a real engine, it will clear any doubts as to whether the throat can function at high engine speeds. 5 refs., 3 tabs., 8 figs.

  6. Bose-Einstein condensation of paraxial light

    Science.gov (United States)

    Klaers, J.; Schmitt, J.; Damm, T.; Vewinger, F.; Weitz, M.

    2011-10-01

    Photons, due to the virtually vanishing photon-photon interaction, constitute to very good approximation an ideal Bose gas, but owing to the vanishing chemical potential a (free) photon gas does not show Bose-Einstein condensation. However, this is not necessarily true for a lower-dimensional photon gas. By means of a fluorescence induced thermalization process in an optical microcavity one can achieve a thermal photon gas with freely adjustable chemical potential. Experimentally, we have observed thermalization and subsequently Bose-Einstein condensation of the photon gas at room temperature. In this paper, we give a detailed description of the experiment, which is based on a dye-filled optical microcavity, acting as a white-wall box for photons. Thermalization is achieved in a photon number-conserving way by photon scattering off the dye molecules, and the cavity mirrors both provide an effective photon mass and a confining potential-key prerequisites for the Bose-Einstein condensation of photons. The experimental results are in good agreement with both a statistical and a simple rate equation model, describing the properties of the thermalized photon gas.

  7. Fluegas condensation of domestic fuels. Kotimaisten polttoaineiden savukaasulauhdutus

    Energy Technology Data Exchange (ETDEWEB)

    Kankkunen, A; Fagerholm, N E

    1988-01-01

    The suitability of domestic fuel for condensation heat recovery was studied. With the developed computer program, enthalpies of flue gas as function of temperature were computed and also the theoretical advandages aquired by condensation were compared with different fuels. The maximal advantages of condensation were 39 % with wooden chips and 31 % with peat. The domestic fuels were found to be useful for condensation heat recovery because of the high water content and the high dewpoint of flu egas. Condensation was found to have a purifying effect on flue gases. It was found experimentaly that 30 % the sulfur of the peat dissolved to the condensed liquid. The composition of condensed liquid of peat- and wooden chip flue gases was studied to find out the corrosion and enviromental effects. The risk of corrosion to metallic heat exhanger was concluded from the compositio of peat condensat. Chip condensate was found to be almost neutral. Normally the condensate liquids were fit for sewering without aftertreatment. Heat transfer coefficient from flue gases to the wall of the condenser was measured to be 150-170 W/Km{sup 2}. Heat transfer coefficients were three times higher compared to condensing heat transfer.

  8. Condensed matter analogues of cosmology

    Science.gov (United States)

    Kibble, Tom; Srivastava, Ajit

    2013-10-01

    liveliest. A number of new experiments are reported here studying the dynamical evolution of domains and defects. Another phenomenon that played a key early role was the formation of vortices in the normal-to-superfluid transition in liquid helium-3. The complicated nature of the order parameter energy surface gives rise to a variety of intriguing effects. This too is still a vigorous field. Superconductivity is a special case because the symmetry that is broken is a gauge symmetry. This is also true in fundamental particle physics theories of relevance to cosmology, and for that reason experiments on superconductors are of particular interest to cosmologists. The situation in this case is more complicated because there are competing mechanisms of defect formation. Experiments in the field have not proved easy, either to perform or to interpret, but the papers in this collection show that good progress has been made of late. In recent years a new type of system has proved immensely fruitful, namely atomic Bose-Einstein or Fermi-gas condensates. Experiments on condensates with tunable parameters have in general provided broad support for the theory, and have also revealed a wide range of interesting and novel features, with intriguing possible analogues in cosmology (e.g. causal horizons and particle creation). The basic idea of the Kibble-Zurek mechanism has been shown to be relevant in this whole range of systems. But numerous complexities have also emerged, concerned for example with the role of inhomogeneity or the existence of composite defects. The field is still developing rapidly. Acknowledgments Finally, we would like to thank all the authors who have contributed to this issue, and the staff of Journal of Physics: Condensed Matter who have made it possible. Condensed matter analogues of cosmology contents Condensed matter analogues of cosmologyTom Kibble and Ajit Srivastava Symmetry breaking in nematic liquid crystals: analogy with cosmology and magnetismR Repnik, A

  9. Gas-solid heat exchange in a fibrous metallic material measured by a heat regenerator technique

    NARCIS (Netherlands)

    Golombok, M.; Jariwala, H.; Shirvill, C.

    1990-01-01

    The convective heat transfer properties of a porous metallic fibre material used in gas surface combustion burners are studied. The important parameter governing the heat transfer between hot gas and metal fibre—the heat transfer coefficient—is measured using a non-steady-state method based on

  10. Gas

    International Nuclear Information System (INIS)

    1996-01-01

    The French government has decided to modify the conditions of extension of local natural gas authorities to neighbouring districts. The European Union is studying the conditions of internal gas market with the objective of more open markets although considering public service requirements

  11. Preparation of nanostructured ZrO2 thin films by using spray pyrolysis technique for gas sensing application

    International Nuclear Information System (INIS)

    Deshmukh, S.B.; Bari, R.H.; Jain, G.H.

    2013-01-01

    In present work the nano-structured pure ZrO 2 thin films were prepared using spray pyrolysis techniques. The aqueous solution of ZrCl 4 , was used as a precursor with flow rate controlled 5 mI/min. The films were synthesized on glass substrate between temperature 250-400℃ and subjected to different analytical characterization like SEM, XRD, TEM, FTIR, UV, TGA-DTA/DSC. The gas sensing performances of various gases were tested in different operating temperature range. The sensitivity, selectivity, response and recovery time for H 2 S gas was discussed. Also nano structured grain size discussed. (author)

  12. Determining of Degradation and Digestion Coefficients of Canola meal Using of In situ and Gas production Techniques

    OpenAIRE

    Younes Tahmazi; Akbar Taghizadeh; Yousef Mehmannavaz; Mehdi Moghaddam

    2015-01-01

    This study was carried out to the determination of nutritive value of canola meal using naylon bag and cumulative gas production techniques in Gizel sheep. Tow fistulated Gizel sheep with average BW 45±2 kg used in a complete randomized design. The cumulative gas production was measured at 2, 4, 6, 8, 12, 16, 24, 36 and 48 h and ruminal DM and CP disappearance were measured up to 96 h. Coefficients of soluble CP degradation of canola meal (A), canola meal treated with 0.5% urea (B) and canola...

  13. Sedimentary condensation and authigenesis

    Science.gov (United States)

    Föllmi, Karl

    2016-04-01

    Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

  14. Increasing the efficiency of the condensing boiler

    Science.gov (United States)

    Zaytsev, ON; Lapina, EA

    2017-11-01

    Analysis of existing designs of boilers with low power consumption showed that the low efficiency of the latter is due to the fact that they work in most cases when the heating period in the power range is significantly less than the nominal power. At the same time, condensing boilers do not work in the most optimal mode (in condensing mode) in the central part of Russia, a significant part of their total operating time during the heating season. This is due to existing methods of equipment selection and joint operation with heating systems with quantitative control of the coolant. It was also revealed that for the efficient operation of the heating system, it is necessary to reduce the inertia of the heat generating equipment. Theoretical patterns of thermal processes in the furnace during combustion gas at different radiating surfaces location schemes considering the influence of the very furnace configuration, characterized in that to reduce the work condensing boiler in conventional gas boiler operation is necessary to maintain a higher temperature in the furnace (in the part where spiral heat exchangers are disposed), which is possible when redistributing heat flow - increase the proportion of radiant heat from the secondary burner emitter allow Perey For the operation of the condensing boiler in the design (condensation) mode practically the entire heating period.

  15. Physics of condensed matter

    CERN Document Server

    Misra, Prasanta K

    2012-01-01

    Physics of Condensed Matter is designed for a two-semester graduate course on condensed matter physics for students in physics and materials science. While the book offers fundamental ideas and topic areas of condensed matter physics, it also includes many recent topics of interest on which graduate students may choose to do further research. The text can also be used as a one-semester course for advanced undergraduate majors in physics, materials science, solid state chemistry, and electrical engineering, because it offers a breadth of topics applicable to these majors. The book be

  16. Which is the most efficient agent for the diffusion of a high-performance technology? Study of the gas-burning condensing boilers'market in four European countries

    International Nuclear Information System (INIS)

    Cauret, L.; Adnot, J.; Haug, J.; Weber, Ch.

    1999-01-01

    The diffusion of technology is often confronted to numerous barriers (market, economical, social...). The combination of strategies along the partners' chain - equipment manufacturer, utility, government, retailer, installer and customer - contributes to the success or the failure of a diffusion. For a given technology, the comparison of different national markets can help to understand why diffusion programs are successful in a country and not in another one. The gas-burning condensing boilers is a good example. It is theoretically the post efficient boiler with LHV efficiency above 100 %, which guarantee an attractive pay-back period for an individual unit (below 10 years) or for a collective equipment (below 5 years). It also induces lower CO 2 and NO x emissions. But the success on the market of this highly-efficient technology, designed in the seventies, has been dramatically different according to the country. The authors reconstitute these market evolutions for the four countries (France, Germany, Great Britain and Netherlands). Furthermore, the link between sales and strategy of main parties involved ( equipment maker, utility, government, retailer, installer and customer - is analysed throughout the past and current promoting methods implemented for their development (R and D supports by utility, subsidies to customers, subsidies to installers...). Finally, the authors prove the role of the involved partners' chain and of the management of subsidies as determining factors for any market development. (authors)

  17. [Determination of acetanilide herbicide residues in tea by gas chromatography-mass spectrometry with two different ionization techniques].

    Science.gov (United States)

    Shen, Weijian; Xu, Jinzhong; Yang, Wenquan; Shen, Chongyu; Zhao, Zengyun; Ding, Tao; Wu, Bin

    2007-09-01

    An analytical method of solid phase extraction-gas chromatography-mass spectrometry with two different ionization techniques was established for simultaneous determination of 12 acetanilide herbicide residues in tea-leaves. Herbicides were extracted from tea-leaf samples with ethyl acetate. The extract was cleaned-up on an active carbon SPE column connected to a Florisil SPE column. Analytical screening was determined by the technique of gas chromatography (GC)-mass spectrometry (MS) in the selected ion monitoring (SIM) mode with either electron impact ionization (EI) or negative chemical ionization (NCI). It is reliable and stable that the recoveries of all herbicides were in the range from 50% to 110% at three spiked levels, 10 microg/kg, 20 microg/kg and 40 microg/kg, and the relative standard deviations (RSDs) were no more than 10.9%. The two different ionization techniques are complementary as more ion fragmentation information can be obtained from the EI mode while more molecular ion information from the NCI mode. By comparison of the two techniques, the selectivity of NCI-SIM was much better than that of EI-SIM method. The sensitivities of the both techniques were high, the limit of quantitative (LOQ) for each herbicide was no more than 2.0 microg/kg, and the limit of detection (LOD) with NCI-SIM technique was much lower than that of EI-SIM when analyzing herbicides with several halogen atoms in the molecule.

  18. Two Inexpensive and Non-destructive Techniques to Correct for Smaller-Than-Gasket Leaf Area in Gas Exchange Measurements

    Directory of Open Access Journals (Sweden)

    Andreas M. Savvides

    2018-04-01

    Full Text Available The development of technology, like the widely-used off-the-shelf portable photosynthesis systems, for the quantification of leaf gas exchange rates and chlorophyll fluorescence offered photosynthesis research a massive boost. Gas exchange parameters in such photosynthesis systems are calculated as gas exchange rates per unit leaf area. In small chambers (<10 cm2, the leaf area used by the system for these calculations is actually the internal gasket area (AG, provided that the leaf covers the entire AG. In this study, we present two inexpensive and non-destructive techniques that can be used to easily quantify the enclosed leaf area (AL of plant species with leaves of surface area much smaller than the AG, such as that of cereal crops. The AL of the cereal crop species studied has been measured using a standard image-based approach (iAL and estimated using a leaf width-based approach (wAL. iAL and wAL did not show any significant differences between them in maize, barley, hard and soft wheat. Similar results were obtained when the wAL was tested in comparison with iAL in different positions along the leaf in all species studied. The quantification of AL and the subsequent correction of leaf gas exchange parameters for AL provided a precise quantification of net photosynthesis and stomatal conductance especially with decreasing AL. This study provides two practical, inexpensive and non-destructive solutions to researchers dealing with photosynthesis measurements on small-leaf plant species. The image-based technique can be widely used for quantifying AL in many plant species despite their leaf shape. The leaf width-based technique can be securely used for quantifying AL in cereal crop species such as maize, wheat and barley along the leaf. Both techniques can be used for a wide range of gasket shapes and sizes with minor technique-specific adjustments.

  19. Gas Source Techniques for Molecular Beam Epitaxy of Highly Mismatched Ge Alloys

    OpenAIRE

    Chad A. Stephenson; Miriam Gillett-Kunnath; William A. O’Brien; Robert Kudrawiec; Mark A. Wistey

    2016-01-01

    Ge and its alloys are attractive candidates for a laser compatible with silicon integrated circuits. Dilute germanium carbide (Ge1−xCx) offers a particularly interesting prospect. By using a precursor gas with a Ge4C core, C can be preferentially incorporated in substitutional sites, suppressing interstitial and C cluster defects. We present a method of reproducible and upscalable gas synthesis of tetrakis(germyl)methane, or (H3Ge)4C, followed by the design of a hybrid gas/solid-source molecu...

  20. Technical note: A simple back-mounted harness for grazing dairy cows to facilitate the sulfur hexafluoride tracer gas technique.

    Science.gov (United States)

    van Wyngaard, Josef D V; Meeske, Robin; Erasmus, Lourens J

    2018-03-01

    We describe here a cattle harness to attach a gas collection vessel to facilitate the sulfur hexafluoride (SF 6 ) tracer gas technique. The harness consists of 2 major components: (1) a lightweight, robust body fabricated from an equine surcingle or lunge roller with padded thoracic trapezius pressure points, a bespoke shaping shaft for spine support, and adjustable buckles on both sides; and (2) an elastic flank-strap to prevent the harness from dislodging. The spine support consists of stainless steel laminated with carbon fiber. This support minimizes the contact area with the animal's skin, relieves the spine area of pressure, and creates free flow of ambient air below the platform, reducing sweat accumulation and hence preventing skin lesions. The harness weighs approximately 1.2 kg, allows for attachment of 2 gas collection vessels (animal and background sample), and is cost effective. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.