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Sample records for gay hydrate production

  1. Comparative Assessment of Advanced Gay Hydrate Production Methods

    Energy Technology Data Exchange (ETDEWEB)

    M. D. White; B. P. McGrail; S. K. Wurstner

    2009-06-30

    Displacing natural gas and petroleum with carbon dioxide is a proven technology for producing conventional geologic hydrocarbon reservoirs, and producing additional yields from abandoned or partially produced petroleum reservoirs. Extending this concept to natural gas hydrate production offers the potential to enhance gas hydrate recovery with concomitant permanent geologic sequestration. Numerical simulation was used to assess a suite of carbon dioxide injection techniques for producing gas hydrates from a variety of geologic deposit types. Secondary hydrate formation was found to inhibit contact of the injected CO{sub 2} regardless of injectate phase state, thus diminishing the exchange rate due to pore clogging and hydrate zone bypass of the injected fluids. Additional work is needed to develop methods of artificially introducing high-permeability pathways in gas hydrate zones if injection of CO{sub 2} in either gas, liquid, or micro-emulsion form is to be more effective in enhancing gas hydrate production rates.

  2. Detection and Production of Methane Hydrate

    Energy Technology Data Exchange (ETDEWEB)

    George Hirasaki; Walter Chapman; Gerald Dickens; Colin Zelt; Brandon Dugan; Kishore Mohanty; Priyank Jaiswal

    2011-12-31

    This project seeks to understand regional differences in gas hydrate systems from the perspective of as an energy resource, geohazard, and long-term climate influence. Specifically, the effort will: (1) collect data and conceptual models that targets causes of gas hydrate variance, (2) construct numerical models that explain and predict regional-scale gas hydrate differences in 2-dimensions with minimal 'free parameters', (3) simulate hydrocarbon production from various gas hydrate systems to establish promising resource characteristics, (4) perturb different gas hydrate systems to assess potential impacts of hot fluids on seafloor stability and well stability, and (5) develop geophysical approaches that enable remote quantification of gas hydrate heterogeneities so that they can be characterized with minimal costly drilling. Our integrated program takes advantage of the fact that we have a close working team comprised of experts in distinct disciplines. The expected outcomes of this project are improved exploration and production technology for production of natural gas from methane hydrates and improved safety through understanding of seafloor and well bore stability in the presence of hydrates. The scope of this project was to more fully characterize, understand, and appreciate fundamental differences in the amount and distribution of gas hydrate and how this would affect the production potential of a hydrate accumulation in the marine environment. The effort combines existing information from locations in the ocean that are dominated by low permeability sediments with small amounts of high permeability sediments, one permafrost location where extensive hydrates exist in reservoir quality rocks and other locations deemed by mutual agreement of DOE and Rice to be appropriate. The initial ocean locations were Blake Ridge, Hydrate Ridge, Peru Margin and GOM. The permafrost location was Mallik. Although the ultimate goal of the project was to understand

  3. Behaviour of gas production from type 3 hydrate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Pooladi-Darvish, M. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering]|[Fekete Associates Inc., Calgary, AB (Canada); Zatsepina, O. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering; Hong, H. [Fekete Associates Inc., Calgary, AB (Canada)

    2008-07-01

    The possible role of gas hydrates as a potential energy resource was discussed with particular reference to methods for estimating the rate of gas production from hydrate reservoirs under different operating conditions. This paper presented several numerical simulations studies of gas production from type 3 hydrate reservoirs in 1-D and 2-D geometries. Type 3 reservoirs include gas production from hydrate-reservoirs that lie totally within the hydrate stability zone and are sandwiched by impermeable layers on top and bottom. The purpose of this study was to better understand hydrate decomposition by depressurization. The study questioned whether 1-D modeling of type 3 hydrate reservoirs is a reasonable approximation. It also determined whether gas rate increases or decreases with time. The important reservoir characteristics for determining the rate of gas production were identified. Last, the study determined how competition between fluid and heat flow affects hydrate decomposition. This paper also described the relation and interaction between the heat and fluid flow mechanisms in depressurization of type 3 hydrate reservoirs. All results of 1-D and 2-D numerical simulation and analyses were generated using the STARS simulator. It was shown that the rate of gas production depends on the initial pressure/temperature conditions and permeability of the hydrate bearing formation. A high peak rate may be achieved under favourable conditions, but this peak rate is obtained after an initial period where the rate of gas production increases with time. The heat transfer in the direction perpendicular to the direction of fluid flow is significant, requiring 2D modeling. The hydraulic diffusivity is low because of the low permeability of hydrate-bearing formations. This could result in competition between heat and fluid flow, thereby influencing the behaviour of decomposition. 6 refs., 3 tabs., 12 figs.

  4. Development of hydrate risk quantification in oil and gas production

    Science.gov (United States)

    Chaudhari, Piyush N.

    Subsea flowlines that transport hydrocarbons from wellhead to the processing facility face issues from solid deposits such as hydrates, waxes, asphaltenes, etc. The solid deposits not only affect the production but also pose a safety concern; thus, flow assurance is significantly important in designing and operating subsea oil and gas production. In most subsea oil and gas operations, gas hydrates form at high pressure and low temperature conditions, causing the risk of plugging flowlines, with a undesirable impact on production. Over the years, the oil and gas industry has shifted their perspective from hydrate avoidance to hydrate management given several parameters such as production facility, production chemistry, economic and environmental concerns. Thus, understanding the level of hydrate risk associated with subsea flowlines is an important in developing efficient hydrate management techniques. In the past, hydrate formation models were developed for various flow-systems (e.g., oil dominated, water dominated, and gas dominated) present in the oil and gas production. The objective of this research is to extend the application of the present hydrate prediction models for assessing the hydrate risk associated with subsea flowlines that are prone to hydrate formation. It involves a novel approach for developing quantitative hydrate risk models based on the conceptual models built from the qualitative knowledge obtained from experimental studies. A comprehensive hydrate risk model, that ranks the hydrate risk associated with the subsea production system as a function of time, hydrates, and several other parameters, which account for inertial, viscous, interfacial forces acting on the flow-system, is developed for oil dominated and condensate systems. The hydrate plugging risk for water dominated systems is successfully modeled using The Colorado School of Mines Hydrate Flow Assurance Tool (CSMHyFAST). It is found that CSMHyFAST can be used as a screening tool in

  5. METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST

    Energy Technology Data Exchange (ETDEWEB)

    Thomas E. Williams; Keith Millheim; Bill Liddell

    2005-03-01

    Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Oil-field engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in Arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrates agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored the HOT ICE No. 1 on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was designed, constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. Unfortunately, no gas hydrates were encountered in this well; however, a wealth of information was generated

  6. Ground movements associated with gas hydrate production

    International Nuclear Information System (INIS)

    Siriwardane, H.J.; Kutuk, B.

    1992-03-01

    This report deals with a study directed towards a modeling effort on production related ground movements and subsidence resulting from hydrate dissociation. The goal of this research study was to evaluate whether there could be subsidence related problems that could be an impediment to hydrate production. During the production of gas from a hydrate reservoir, it is expected that porous reservoir matrix becomes more compressible which may cause reservoir compression (compaction) under the influence of overburden weight. The overburden deformations can propagate its influence upwards causing subsidence near the surface where production equipment will be located. In the present study, the reservoir compaction is modeled by using the conventional ''stress equilibrium'' approach. In this approach, the overburden strata move under the influence of body force (i.e. self weight) in response to the ''cavity'' generated by reservoir depletion. The present study is expected to provide a ''lower bound'' solution to the subsidence caused by hydrate reservoir depletion. The reservoir compaction anticipated during hydrate production was modeled by using the finite element method, which is a powerful computer modeling technique. The ground movements at the reservoir roof (i.e. reservoir compression) cause additional stresses and disturbance in the overburden strata. In this study, the reservoir compaction was modeled by using the conventional ''stress equilibrium'' approach. In this approach, the overburden strata move under the influence of body force (i.e. self weight) in response to the ''cavity'' generated by reservoir depletion. The resulting stresses and ground movements were computed by using the finite element method. Based on the parameters used in this investigation, the maximum ground subsidence could vary anywhere from 0.50 to 6.50 inches depending on the overburden depth and the size of the depleted hydrate reservoir

  7. METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST

    Energy Technology Data Exchange (ETDEWEB)

    Ali Kadaster; Bill Liddell; Tommy Thompson; Thomas Williams; Michael Niedermayr

    2005-02-01

    Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project was a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. The work scope included drilling and coring a well (Hot Ice No. 1) on Anadarko leases beginning in FY 2003 and completed in 2004. During the first drilling season, operations were conducted at the site between January 28, 2003 to April 30, 2003. The well was spudded and drilled to a depth of 1403 ft. Due to the onset of warmer weather, work was then suspended for the season. Operations at the site were continued after the tundra was re-opened the following season. Between January 12, 2004 and March 19, 2004, the well was drilled and cored to a final depth of 2300 ft. An on-site core analysis laboratory was built and implemented for determining physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. Final efforts of the project are to correlate geology, geophysics, logs, and drilling and

  8. Hydrate prevention in petroleum production sub sea system

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Paula L.F.; Rocha, Humberto A.R. [Universidade Estacio de Sa (UNESA), Rio de Janeiro, RJ (Brazil); Rodrigues, Antonio P. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2012-07-01

    In spite of the merits of the several hydrate prevention techniques used nowadays, such as: chemical product injection for inhibition and use of thick thermal insulate lines; hydrates per times happen and they are responsible for considerable production losses. Depressurization techniques can be used so much for prevention as in the remediation. Some hydrate removal techniques need a rig or vessel, resources not readily available and with high cost, reason that limits such techniques just for remediation and not for prevention. In the present work it is proposed and described an innovative depressurization system, remote and resident, for hydrate prevention and removal, applicable as for individual sub sea wells as for grouped wells by manifold. Based on low cost jet pumps, without movable parts and with a high reliability, this technique allows hydrate prevention or remediation in a fast and remote way, operated from the production unit. The power fluid line and fluid return line can be integrated in the same umbilical or annulus line structure, without significant increase in the construction costs and installation. It is not necessary to wait for expensive resource mobilization, sometimes not available quickly, such as: vessels or rigs. It still reduces the chemical product consumption and permits to depressurized stopped lines. Other additional advantage, depressurization procedure can be used in the well starting, removing fluid until riser emptying. (author)

  9. Challenges, uncertainties and issues facing gas production from gas hydrate deposits

    Energy Technology Data Exchange (ETDEWEB)

    Moridis, G.J.; Collett, T.S.; Pooladi-Darvish, M.; Hancock, S.; Santamarina, C.; Boswell, R.; Kneafsey, T.; Rutqvist, J.; Kowalsky, M.; Reagan, M.T.; Sloan, E.D.; Sum, A.K.; Koh, C.

    2010-11-01

    The current paper complements the Moridis et al. (2009) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas hydrate petroleum system, to discuss advances, requirement and suggested practices in gas hydrate (GH) prospecting and GH deposit characterization, and to review the associated technical, economic and environmental challenges and uncertainties, including: the accurate assessment of producible fractions of the GH resource, the development of methodologies for identifying suitable production targets, the sampling of hydrate-bearing sediments and sample analysis, the analysis and interpretation of geophysical surveys of GH reservoirs, well testing methods and interpretation of the results, geomechanical and reservoir/well stability concerns, well design, operation and installation, field operations and extending production beyond sand-dominated GH reservoirs, monitoring production and geomechanical stability, laboratory investigations, fundamental knowledge of hydrate behavior, the economics of commercial gas production from hydrates, and the associated environmental concerns.

  10. Spatial resolution of gas hydrate and permeability changes from ERT data in LARS simulating the Mallik gas hydrate production test

    Science.gov (United States)

    Priegnitz, Mike; Thaler, Jan; Spangenberg, Erik; Schicks, Judith M.; Abendroth, Sven

    2014-05-01

    The German gas hydrate project SUGAR studies innovative methods and approaches to be applied in the production of methane from hydrate-bearing reservoirs. To enable laboratory studies in pilot scale, a large reservoir simulator (LARS) was realized allowing for the formation and dissociation of gas hydrates under simulated in-situ conditions. LARS is equipped with a series of sensors. This includes a cylindrical electrical resistance tomography (ERT) array composed of 25 electrode rings featuring 15 electrodes each. The high-resolution ERT array is used to monitor the spatial distribution of the electrical resistivity during hydrate formation and dissociation experiments over time. As the present phases of poorly conducting sediment, well conducting pore fluid, non-conducting hydrates, and isolating free gas cover a wide range of electrical properties, ERT measurements enable us to monitor the spatial distribution of these phases during the experiments. In order to investigate the hydrate dissociation and the resulting fluid flow, we simulated a hydrate production test in LARS that was based on the Mallik gas hydrate production test (see abstract Heeschen et al., this volume). At first, a hydrate phase was produced from methane saturated saline water. During the two months of gas hydrate production we measured the electrical properties within the sediment sample every four hours. These data were used to establish a routine estimating both the local degrees of hydrate saturation and the resulting local permeabilities in the sediment's pore space from the measured resistivity data. The final gas hydrate saturation filled 89.5% of the total pore space. During hydrate dissociation, ERT data do not allow for a quantitative determination of free gas and remaining gas hydrates since both phases are electrically isolating. However, changes are resolved in the spatial distribution of the conducting liquid and the isolating phase with gas being the only mobile isolating phase

  11. METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST

    Energy Technology Data Exchange (ETDEWEB)

    Donn McGuire; Steve Runyon; Richard Sigal; Bill Liddell; Thomas Williams; George Moridis

    2005-02-01

    Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is in the final stages of a cost-shared partnership between Maurer Technology, Noble Corporation, Anadarko Petroleum, and the U.S. Department of Energy's Methane Hydrate R&D program. The purpose of the project is to build on previous and ongoing R&D in the area of onshore hydrate deposition to identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. Hot Ice No. 1 was planned to test the Ugnu and West Sak sequences for gas hydrates and a concomitant free gas accumulation on Anadarko's 100% working interest acreage in section 30 of Township 9N, Range 8E of the Harrison Bay quadrangle of the North Slope of Alaska. The Ugnu and West Sak intervals are favorably positioned in the hydrate-stability zone over an area extending from Anadarko's acreage westward to the vicinity of the aforementioned gas-hydrate occurrences. This suggests that a large, north-to-south trending gas-hydrate accumulation may exist in that area. The presence of gas shows in the Ugnu and West Sak reservoirs in wells situated eastward and down dip of the Hot Ice location indicate that a free-gas accumulation may be trapped by gas hydrates. The Hot Ice No. 1 well was designed to core from the surface to the base of the West Sak interval using the

  12. Challenges, uncertainties, and issues facing gas production from gas-hydrate deposits

    Science.gov (United States)

    Moridis, G.J.; Collett, T.S.; Pooladi-Darvish, M.; Hancock, S.; Santamarina, C.; Boswel, R.; Kneafsey, T.; Rutqvist, J.; Kowalsky, M.B.; Reagan, M.T.; Sloan, E.D.; Sum, A.K.; Koh, C.A.

    2011-01-01

    The current paper complements the Moridis et al. (2009) review of the status of the effort toward commercial gas production from hydrates. We aim to describe the concept of the gas-hydrate (GH) petroleum system; to discuss advances, requirements, and suggested practices in GH prospecting and GH deposit characterization; and to review the associated technical, economic, and environmental challenges and uncertainties, which include the following: accurate assessment of producible fractions of the GH resource; development of methods for identifying suitable production targets; sampling of hydrate-bearing sediments (HBS) and sample analysis; analysis and interpretation of geophysical surveys of GH reservoirs; well-testing methods; interpretation of well-testing results; geomechanical and reservoir/well stability concerns; well design, operation, and installation; field operations and extending production beyond sand-dominated GH reservoirs; monitoring production and geomechanical stability; laboratory investigations; fundamental knowledge of hydrate behavior; the economics of commercial gas production from hydrates; and associated environmental concerns. ?? 2011 Society of Petroleum Engineers.

  13. Preliminary report on the economics of gas production from natural gas hydrates

    International Nuclear Information System (INIS)

    Walsh, M.; Wilson, S.; Patil, S.; Moridis, G.; Boswell, R.; Koh, C.; Sloan, D.

    2008-01-01

    Gas hydrates are solid crystalline compounds in which gas molecules reside inside cages that are formed by hydrogen-bonded water molecules in a crystal lattice. At particularly low temperatures and high pressures, a guest molecule will combine with water to form gas hydrates. Gas hydrates are found in two different settings in which the temperature and pressure conditions are suitable for their existence, notably in Arctic permafrost regions and below the seafloor. Because of the size of this possible future resource, if any of the gas in hydrates can be proven to be economically recoverable, then production from gas hydrates could become an important portion of the world's energy portfolio as demand for natural gas increases along with the technology to compress and distribute natural gas to distant markets. This paper presented a compilation of economic research that was conducted on the resource potential of gas hydrates. The paper reported a preliminary estimate of the price of natural gas that may lead to economically-viable production from North American Arctic region hydrates. The paper also discussed the implications of a recent study on the production of class 3 marine hydrate deposits from the Gulf of Mexico. The state of the art technologies and methods in hydrate reservoir modeling and hydrate reservoir production and petrophysical testing were also discussed. It was concluded that the somewhat optimistic results presented in this report should be interpreted with caution, however, the economically-viable gas production from hydrates was not an unreasonable scenario. 23 refs., 2 tabs., 10 figs

  14. Hydrate-Bearing Clayey Sediments: Morphology, Physical Properties, Production and Engineering/Geological Implications

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Sheng [Georgia Tech Research Corporation, Atlanta, GA (United States); Santamarina, J. Carlos [King Abdulaziz Univ., Jeddah (Saudi Arabia)

    2017-12-30

    Fine-grained sediments host more than 90 percent of global gas hydrate accumulation. However, hydrate formation in clay-dominated sediments is less understood and characterized than other types of hydrate occurrence. There is an inadequate understanding of hydrate formation mechanisms, segregation structures, hydrate lens topology, system connectivity, and physical macro-scale properties of clay-dominated hydrate-bearing sediments. This situation hinders further analyses of the global carbon budget as well as engineering challenges/solutions related to hydrate instability and production. This project studies hydrate-bearing clay-dominated sediments with emphasis on the enhanced fundamental understanding of hydrate formation and resulting morphology, the development laboratory techniques to emulate natural hydrate formations, the assessment of analytical tools to predict physical properties, the evaluation of engineering and geological implications, and the advanced understanding of gas production potential from finegrained sediments.

  15. Methane Production and Carbon Capture by Hydrate Swapping

    DEFF Research Database (Denmark)

    Mu, Liang; von Solms, Nicolas

    2017-01-01

    There are essentially two different approaches to producing methane from natural gas hydrate reservoirs, either bring the hydrate out of its thermodynamic stability region or expose the hydrate to a substance that will form a more stable hydrate structure, forcing an in situ swapping of the trapped...... experimental runs were performed to examine the influence of operating conditions on methane production by CO2/(CO2 + N2) injection in the temperature range of 274.15–277.15 K and 7.039–10.107 MPa pressure. Our results show that the use of the (CO2 + N2) binary gas mixture is advantageous compared to the use...

  16. Hydrate bearing clayey sediments: Formation and gas production concepts

    KAUST Repository

    Jang, Jaewon; Santamarina, Carlos

    2016-01-01

    Hydro-thermo-chemo and mechanically coupled processes determine hydrate morphology and control gas production from hydrate-bearing sediments. Force balance, together with mass and energy conservation analyses anchored in published data provide robust asymptotic solutions that reflect governing processes in hydrate systems. Results demonstrate that hydrate segregation in clayey sediments results in a two-material system whereby hydrate lenses are surrounded by hydrate-free water-saturated clay. Hydrate saturation can reach ≈2% by concentrating the excess dissolved gas in the pore water and ≈20% from metabolizable carbon. Higher hydrate saturations are often found in natural sediments and imply methane transport by advection or diffusion processes. Hydrate dissociation is a strongly endothermic event; the available latent heat in a reservoir can sustain significant hydrate dissociation without triggering ice formation during depressurization. The volume of hydrate expands 2-to-4 times upon dissociation or CO2single bondCH4 replacement. Volume expansion can be controlled to maintain lenses open and to create new open mode discontinuities that favor gas recovery. Pore size is the most critical sediment parameter for hydrate formation and gas recovery and is controlled by the smallest grains in a sediment. Therefore any characterization must carefully consider the amount of fines and their associated mineralogy.

  17. Hydrate bearing clayey sediments: Formation and gas production concepts

    KAUST Repository

    Jang, Jaewon

    2016-06-20

    Hydro-thermo-chemo and mechanically coupled processes determine hydrate morphology and control gas production from hydrate-bearing sediments. Force balance, together with mass and energy conservation analyses anchored in published data provide robust asymptotic solutions that reflect governing processes in hydrate systems. Results demonstrate that hydrate segregation in clayey sediments results in a two-material system whereby hydrate lenses are surrounded by hydrate-free water-saturated clay. Hydrate saturation can reach ≈2% by concentrating the excess dissolved gas in the pore water and ≈20% from metabolizable carbon. Higher hydrate saturations are often found in natural sediments and imply methane transport by advection or diffusion processes. Hydrate dissociation is a strongly endothermic event; the available latent heat in a reservoir can sustain significant hydrate dissociation without triggering ice formation during depressurization. The volume of hydrate expands 2-to-4 times upon dissociation or CO2single bondCH4 replacement. Volume expansion can be controlled to maintain lenses open and to create new open mode discontinuities that favor gas recovery. Pore size is the most critical sediment parameter for hydrate formation and gas recovery and is controlled by the smallest grains in a sediment. Therefore any characterization must carefully consider the amount of fines and their associated mineralogy.

  18. ConocoPhillips Gas Hydrate Production Test

    Energy Technology Data Exchange (ETDEWEB)

    Schoderbek, David [ConocoPhillips Co., Houston, TX (United States); Farrell, Helen [ConocoPhillips Co., Houston, TX (United States); Howard, James [ConocoPhillips Co., Houston, TX (United States); Raterman, Kevin [ConocoPhillips Co., Houston, TX (United States); Silpngarmlert, Suntichai [ConocoPhillips Co., Houston, TX (United States); Martin, Kenneth [ConocoPhillips Co., Houston, TX (United States); Smith, Bruce [ConocoPhillips Co., Houston, TX (United States); Klein, Perry [ConocoPhillips Co., Houston, TX (United States)

    2013-06-30

    Work began on the ConocoPhillips Gas Hydrates Production Test (DOE award number DE-NT0006553) on October 1, 2008. This final report summarizes the entire project from January 1, 2011 to June 30, 2013.

  19. [Skin hydration and hydrating products].

    Science.gov (United States)

    Duplan, H; Nocera, T

    2018-05-01

    One of the skin's principal functions is to protect the body against its environment by maintaining an effective epidermal barrier, not only against external factors, but also to prevent water loss from the body. Indeed, water homeostasis is vital for the normal physiological functioning of skin. Hydration levels affect not only visible microscopic parameters such as the suppleness and softness of skin, but also molecular parameters, enzyme activities and cellular signalling within the epidermis. The body is continually losing some of its water, but this phenomenon is limited and the optimal hydration gradient in skin is ensured via a set of sophisticated regulatory processes that rely on the functional and dynamic properties of the uppermost level of the skin consisting of the stratum corneum. The present article brings together data recently acquired in the fields of skin hydration and the characterisation of dehydrated or dry skin, whether through study of the regulatory processes involved or as a result of changes in the techniques used for in situ measurement, and thus in optimisation of management. Copyright © 2018. Published by Elsevier Masson SAS.

  20. Constant rate natural gas production from a well in a hydrate reservoir

    International Nuclear Information System (INIS)

    Ji Chuang; Ahmadi, Goodarz; Smith, Duane H.

    2003-01-01

    Using a computational model, production of natural gas at a constant rate from a well that is drilled into a confined methane hydrate reservoir is studied. It is assumed that the pores in the reservoir are partially saturated with hydrate. A linearized model for an axisymmetric condition with a fixed well output is used in the analysis. For different reservoir temperatures and various well outputs, time evolutions of temperature and pressure profiles, as well as the gas flow rate in the hydrate zone and the gas region, are evaluated. The distance of the decomposition front from the well as a function of time is also computed. It is shown that to maintain a constant natural gas production rate, the well pressure must be decreased with time. A constant low production rate can be sustained for a long duration of time, but a high production rate demands unrealistically low pressure at the well after a relatively short production time. The simulation results show that the process of natural gas production in a hydrate reservoir is a sensitive function of reservoir temperature and hydrate zone permeability

  1. Experimental hydrate formation and gas production scenarios based on CO{sub 2} sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, J.C.; Howard, J.J. [ConocoPhillips, Bartlesville, OK (United States). Reservoir Laboratories; Baldwin, B.A. [Green Country Petrophysics LLC, Dewey, OK (United States); Ersland, G.; Husebo, J.; Graue, A. [Bergen Univ., Bergen (Norway). Dept. of Physics and Technology

    2008-07-01

    Gas hydrate production strategies have focused on depressurization or thermal stimulation of the reservoir, which in turn leads to hydrate dissociation. In order to evaluate potential production scenarios, the recovery efficiency of the natural gas from hydrate must be known along with the corresponding amounts of produced water. This study focused on the exchange of carbon dioxide (CO{sub 2}) with the natural gas hydrate and the subsequent release of free methane (CH{sub 4}). Laboratory experiments that investigated the rates and mechanisms of hydrate formation in coarse-grained porous media have shown the significance of initial water saturation and salinity on forming methane hydrates. Many of the experiments were performed in a sample holder fitted with an MRI instrument for monitoring hydrate formation. Hydrate-saturated samples were subjected to different procedures to release methane. The rates and efficiency of the exchange process were reproducible over a series of initial conditions. The exchange process was rapid and efficient in that no free water was observed in the core with MRI measurements. Injection of CO{sub 2} into the whole-core hydrate-saturated pore system resulted in methane production at the outlet end. Permeability measurements on these hydrate saturated cores during hydrate formation decreased to low values, but enough for gas transport. The lower permeability values remained constant during the methane-carbon dioxide exchange process in the hydrate structure. 12 refs., 9 figs.

  2. Gas production potential of disperse low-saturation hydrate accumulations in oceanic sediments

    International Nuclear Information System (INIS)

    Moridis, George J.; Sloan, E. Dendy

    2007-01-01

    In this paper, we evaluate the gas production potential of disperse, low-saturation (S H H hydrate-bearing sediments subject to depressurization-induced dissociation over a 10-year production period. We investigate the sensitivity of items (a)-(c) to the following hydraulic properties, reservoir conditions, and operational parameters: intrinsic permeability, porosity, pressure, temperature, hydrate saturation, and constant pressure at which the production well is kept. The results of this study indicate that, despite wide variations in the aforementioned parameters (covering the entire spectrum of such deposits), gas production is very limited, never exceeding a few thousand cubic meters of gas during the 10-year production period. Such low production volumes are orders of magnitude below commonly accepted standards of economic viability, and are further burdened with very unfavorable gas-to-water ratios. The unequivocal conclusion from this study is that disperse, low-S H hydrate accumulations in oceanic sediments are not promising targets for gas production by means of depressurization-induced dissociation, and resources for early hydrate exploitation should be focused elsewhere

  3. Preliminary report on the commercial viability of gas production from natural gas hydrates

    Science.gov (United States)

    Walsh, M.R.; Hancock, S.H.; Wilson, S.J.; Patil, S.L.; Moridis, G.J.; Boswell, R.; Collett, T.S.; Koh, C.A.; Sloan, E.D.

    2009-01-01

    Economic studies on simulated gas hydrate reservoirs have been compiled to estimate the price of natural gas that may lead to economically viable production from the most promising gas hydrate accumulations. As a first estimate, $CDN2005 12/Mscf is the lowest gas price that would allow economically viable production from gas hydrates in the absence of associated free gas, while an underlying gas deposit will reduce the viability price estimate to $CDN2005 7.50/Mscf. Results from a recent analysis of the simulated production of natural gas from marine hydrate deposits are also considered in this report; on an IROR basis, it is $US2008 3.50-4.00/Mscf more expensive to produce marine hydrates than conventional marine gas assuming the existence of sufficiently large marine hydrate accumulations. While these prices represent the best available estimates, the economic evaluation of a specific project is highly dependent on the producibility of the target zone, the amount of gas in place, the associated geologic and depositional environment, existing pipeline infrastructure, and local tariffs and taxes. ?? 2009 Elsevier B.V.

  4. METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST

    Energy Technology Data Exchange (ETDEWEB)

    Richard Sigal; Kent Newsham; Thomas Williams; Barry Freifeld; Timothy Kneafsey; Carl Sondergeld; Shandra Rai; Jonathan Kwan; Stephen Kirby; Robert Kleinberg; Doug Griffin

    2005-02-01

    Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. The work scope drilled and cored a well The Hot Ice No. 1 on Anadarko leases beginning in FY 2003 and completed in 2004. An on-site core analysis laboratory was built and utilized for determining the physical characteristics of the hydrates and surrounding rock. The well was drilled from a new Anadarko Arctic Platform that has a minimal footprint and environmental impact. The final efforts of the project are to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists developing reservoir models. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in this report. The Hot Ice No. 1 well was drilled from the surface to a measured depth of 2300 ft. There was almost 100% core recovery from the bottom of surface casing at 107 ft to total depth. Based on the best estimate of the bottom of the methane hydrate stability zone (which used new data obtained from Hot Ice No. 1 and new analysis of data from adjacent wells), core was recovered over its complete range. Approximately 580 ft of porous, mostly frozen, sandstone and 155 of conglomerate were recovered in the Ugnu Formation and approximately 215 ft of porous sandstone were recovered in the West Sak Formation. There were gas shows in the bottom

  5. Simulation of microwave stimulation for the production of gas from methane hydrate sediment

    International Nuclear Information System (INIS)

    Zhao, Jiafei; Fan, Zhen; Wang, Bin; Dong, Hongsheng; Liu, Yu; Song, Yongchen

    2016-01-01

    Graphical abstract: Schematic diagram illustrating the process of gas production in hydrate-bearing sediment induced by microwave stimulation. Temperature gradients caused by the drop of microwave penetration depth appear in the sediment, leading to a rapid dissociation rate at the upper part of reservoir. - Highlights: • Hydrate dissociation behavior was analyzed in porous media by microwave stimulation. • Microwave stimulation provides sufficient energy conversion for hydrate dissociation. • Hydrate saturation and specific heat capacity of sediment mainly affect efficiency. • Heat conduction decreases temperature gradients promoting homogeneous dissociation. - Abstract: Natural gas hydrates dissociate via an endothermic process. One of the key requirements for any production technique is to supply the heat necessary for this dissociation. In this study, first, a microwave stimulation model for the production of gas from methane hydrate sediment is developed, which includes mass transport, energy conversion and conservation, and intrinsic kinetic reactions as the governing equations. In addition, the theoretical mixing rule of Lichtenecker and Rother is introduced for calculating the average dielectric data of the sediment containing methane hydrates, which affects the penetration of microwaves into the sediment. Next, simulations are performed for investigating gas production, as well as effects of initial water saturation, initial hydrate saturation, and sediment thermal properties induced by microwave stimulation. Moreover, the energy efficiency ratio is employed in the simulation. The simulation results show that microwave stimulation provides timely energy conversion sufficient for promoting the dissociation of hydrates, with rapid, continuous gas production. Temperature gradients caused by the decrease of the microwave penetration depth appear in the reservoir, leading to a rapid dissociation rate in the upper part of the sediment. The energy

  6. Towards understanding the role of amines in the SO2 hydration and the contribution of the hydrated product to new particle formation in the Earth's atmosphere.

    Science.gov (United States)

    Lv, Guochun; Nadykto, Alexey B; Sun, Xiaomin; Zhang, Chenxi; Xu, Yisheng

    2018-08-01

    By theoretical calculations, the gas-phase SO 2 hydration reaction assisted by methylamine (MA) and dimethylamine (DMA) was investigated, and the potential contribution of the hydrated product to new particle formation (NPF) also was evaluated. The results show that the energy barrier for aliphatic amines (MA and DMA) assisted SO 2 hydration reaction is lower than the corresponding that of water and ammonia assisted SO 2 hydration. In these hydration reactions, nearly barrierless reaction (only a barrier of 0.1 kcal mol -1 ) can be found in the case of SO 2  + 2H 2 O + DMA. These lead us to conclude that the SO 2 hydration reaction assisted by MA and DMA is energetically facile. The temporal evolution for hydrated products (CH 3 NH 3 + -HSO 3 - -H 2 O or (CH 3 ) 2 NH 2 + -HSO 3 - -H 2 O) in molecular dynamics simulations indicates that these complexes can self-aggregate into bigger clusters and can absorb water and amine molecules, which means that these hydrated products formed by the hydration reaction may serve as a condensation nucleus to initiate the NPF. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Experimental investigation into methane hydrate production during three-dimensional thermal stimulation with five-spot well system

    International Nuclear Information System (INIS)

    Wang, Yi; Li, Xiao-Sen; Li, Gang; Zhang, Yu; Li, Bo; Chen, Zhao-Yang

    2013-01-01

    Highlights: • The production behaviors of methane hydrate are obtained in the 3-D simulator. • The thermal stimulation method with a five-spot well is used for hydrate production. • The water and gas production, efficiency, recovery, production rate are analyzed. • The effect of injection rate change on the production behavior is investigated. - Abstract: The cubic hydrate simulator (CHS) is used to study the methane hydrate production behaviors in porous media by the thermal stimulation with a five-spot well system. The hot water injection rates range from 10.0 to 40.0 ml/min. The thermal stimulation process is analyzed, and the conclusions are that the hydrate decomposition boundary moves from the central point to the surroundings gradually and finally covers almost the entire hydrate field in the CHS during the thermal stimulation process. The heat conduction plays a more significant role than the convection for the heat diffusion in the thermal stimulation process. The increasing injection rate of the hot water enhances the rate of hydrate decomposition, shortens the production time, and decreases the water production volumes, while it has little influence on the final gas production volumes. Furthermore, the change of the hot water injection rate (R inj ) has little influence on the final gas recovery, however, the higher R inj leads to the higher average production rate and the lower energy efficiency

  8. Gay, Mostly Gay, or Bisexual Leaning Gay? An Exploratory Study Distinguishing Gay Sexual Orientations Among Young Men.

    Science.gov (United States)

    Savin-Williams, Ritch C; Cash, Brian M; McCormack, Mark; Rieger, Gerulf

    2017-01-01

    This exploratory study assessed physiological, behavioral, and self-report measures of sexual and romantic indicators of sexual orientation identities among young men (mean age = 21.9 years) with predominant same-sex sexual and romantic interests: those who described themselves as bisexual leaning gay (n = 11), mostly gay (n = 17), and gay (n = 47). Although they were not significantly distinguishable based on physiological (pupil dilation) responses to nude stimuli, on behavioral and self-report measures a descending linear trend toward the less preferred sex (female) was significant regarding sexual attraction, fantasy, genital contact, infatuation, romantic relationship, sex appeal, and gazing time to the porn stimuli. Results supported a continuum of sexuality with distinct subgroups only for the self-report measure of sexual attraction. The other behavioral and self-report measures followed the same trend but did not significantly differ between the bisexual leaning gay and mostly gay groups, likely the result of small sample size. Results suggest that romantic indicators are as good as sexual measures in assessing sexual orientation and that a succession of logically following groups from bisexual leaning gay, mostly gay, to gay. Whether these three groups are discrete or overlapping needs further research.

  9. PERSEPSI GAY TERHADAP STIGMATISASI GAY OLEH PETUGAS KESEHATAN

    Directory of Open Access Journals (Sweden)

    Yafi Sabila Rosyad

    2015-04-01

    Full Text Available Background: The presence of gays in the community still makes heterosexual as normal sex orientation.Thereareunfair perceptionsof heterosexual group that develop into real behaviorswhicharevery detrimental for homosexuals group in the form of stigmatization against homosexuals.Stigmatization for gay in society also comes fromhealthprofessionals when they think homosexualsconduct violationto theruleof law,social andreligiousvalues.Therefore gays tend to visit certain healthcare providers who are familiar with them or to hide the identity that they are homosexuals.Objective:Todeterminetheperceptionsof gaysregarding gaystigmatizationofhealthcare providers.Methods:A qualitativeby using snowball samplingwith the total of 10participants was applied.TheConceptual Content CognitiveMap(3CMmethods followedby interviewwere utilized to gather data.Results:Six themesregarding gaystigmatizationofhealthcare as perceived by gays as follows: (1 gay isa divergence and contagious; (2 being gay is normal; (3 flamboyant and hedonist personality; (4 exclusiveand bad personality; (5 at high risk of sexually transmitted diseases, lack of self-control, and diseased; and(6 having good personality.Conclusion:Six themes with predominantly negative perceptions regarding stigmatization on gays byhealth careproviders as perceived by gays describe the need of transformation of health care service toincrease the quality of health of minor population like gay.

  10. Numerical simulation studies of gas production scenarios from hydrate accumulations at the Mallik Site, McKenzie Delta, Canada

    International Nuclear Information System (INIS)

    Moridis, George J.; Collett, Timothy S.; Dallimore, Scott R.; Satoh, Tohru; Hancock, Stephen; Weatherill, Brian

    2002-01-01

    The Mallik site represents an onshore permafrost-associated gas hydrate accumulation in the Mackenzie Delta, Northwest Territories, Canada. An 1150 m deep gas hydrate research well was drilled at the site in 1998. The objective of this study is the analysis of various gas production scenarios from several gas-hydrate-bearing zones at the Mallik site. The TOUGH2 general-purpose simulator with the EOSHYDR2 module were used for the analysis. EOSHYDR2 is designed to model the non-isothermal CH(sub 4) (methane) release, phase behavior and flow under conditions typical of methane-hydrate deposits by solving the coupled equations of mass and heat balance, and can describe any combination of gas hydrate dissociation mechanisms. Numerical simulations indicated that significant gas hydrate production at the Mallik site was possible by drawing down the pressure on a thin free-gas zone at the base of the hydrate stability field. Gas hydrate zones with underlying aquifers yielded significant gas production entirely from dissociated gas hydrate, but large amounts of produced water. Lithologically isolated gas-hydrate-bearing reservoirs with no underlying free gas or water zones, and gas-hydrate saturations of at least 50% were also studied. In these cases, it was assumed that thermal stimulation by circulating hot water in the well was the method used to induce dissociation. Sensitivity studies indicated that the methane release from the hydrate accumulations increases with gas-hydrate saturation, the initial formation temperature, the temperature of the circulating water in the well, and the formation thermal conductivity. Methane production appears to be less sensitive to the rock and hydrate specific heat and permeability of the formation

  11. Sensitivity Analysis of Methane Hydrate Reservoirs: Effects of Reservoir Parameters on Gas Productivity and Economics

    Science.gov (United States)

    Anderson, B. J.; Gaddipati, M.; Nyayapathi, L.

    2008-12-01

    This paper presents a parametric study on production rates of natural gas from gas hydrates by the method of depressurization, using CMG STARS. Seven factors/parameters were considered as perturbations from a base-case hydrate reservoir description based on Problem 7 of the International Methane Hydrate Reservoir Simulator Code Comparison Study led by the Department of Energy and the USGS. This reservoir is modeled after the inferred properties of the hydrate deposit at the Prudhoe Bay L-106 site. The included sensitivity variables were hydrate saturation, pressure (depth), temperature, bottom-hole pressure of the production well, free water saturation, intrinsic rock permeability, and porosity. A two-level (L=2) Plackett-Burman experimental design was used to study the relative effects of these factors. The measured variable was the discounted cumulative gas production. The discount rate chosen was 15%, resulting in the gas contribution to the net present value of a reservoir. Eight different designs were developed for conducting sensitivity analysis and the effects of the parameters on the real and discounted production rates will be discussed. The breakeven price in various cases and the dependence of the breakeven price on the production parameters is given in the paper. As expected, initial reservoir temperature has the strongest positive effect on the productivity of a hydrate deposit and the bottom-hole pressure in the production well has the strongest negative dependence. Also resulting in a positive correlation is the intrinsic permeability and the initial free water of the formation. Negative effects were found for initial hydrate saturation (at saturations greater than 50% of the pore space) and the reservoir porosity. These negative effects are related to the available sensible heat of the reservoir, with decreasing productivity due to decreasing available sensible heat. Finally, we conclude that for the base case reservoir, the break-even price (BEP

  12. Geologic and porous media factors affecting the 2007 production response characteristics of the JOGMEC/NRCan/AURORA Mallik gas hydrate production research well

    Energy Technology Data Exchange (ETDEWEB)

    Dallimore, S. R.; Wright, J. F.; Nixon, F. M. [Natural Resources Canada, Sidney, BC (Canada). Geological Survey of Canada; Kurihara, M. [Japan Oil Engineering, Tokyo (Japan); Yamamoto, K.; Fujii, T.; Fujii, K.; Numasawa, M.; Yasuda, M. [Japan Oil, Gas, Metals National Corp., Chiba (Japan). Technical Research Centre; Imasato, Y. [Schlumberger K.K., Fuchinombe (Japan)

    2008-07-01

    The joint research project between Japan Oil, Gas and Metals National Corporation (JOGMEC), Natural Resources Canada (NRCan) and the Aurora Research Institute was conducted in an effort to measure and monitor the response of a terrestrial gas hydrate reservoir to pressure draw down. This paper reviewed the geologic setting and porous media conditions of a concentrated gas hydrate production interval between 1093 and 1105 m. The short-duration production test was conducted at the Mallik site in Canada's Mackenzie Delta in April 2007. The production interval consists of a sand-dominated succession with occasional silty sand interbeds. Gas hydrate occurs primarily within the sediment pore spaces, with concentrations ranging between 50-90 per cent. Experiments on pore water salinity and porous media conditions on pressure-temperature stability suggest that the partition between gas hydrate stability and instability should be considered as a phase boundary zone rather than a discrete threshold. The experiment revealed that there are significant changes to the physical properties following gas hydrate dissociation, with sediments containing no hydrate behaving as unconsolidated sands. A strong reservoir response to pressure draw down was observed with increasing gas flow during the testing period. Sand inflow to the well during the test may be attributed to loss of sediment strength during gas hydrate dissociation, with the sediment behaving as a gasified slurry. It was concluded that the gas flow response observed during the 2007 production test at Mallik was highly influenced by porous media properties and by the geological heterogeneities which may initiate high permeability conduits in sediments within the production interval of the Mallik gas hydrate reservoir. 18 refs., 6 figs.

  13. Effect of Graphene Oxide (GO on the Morphology and Microstructure of Cement Hydration Products

    Directory of Open Access Journals (Sweden)

    Liguo Wang

    2017-12-01

    Full Text Available In this study, the effects of graphene oxide (GO on the microstructure of cement mortars were studied using scanning electron microscopy (SEM, thermogravimetric (TG, and X-ray diffraction (XRD techniques. Cement mortar samples with different proportions of GO (0.02, 0.04, 0.06, and 0.08 wt % based on the weight of cement were prepared. The test results showed that GO affected the crystallization of cement hydration products, C–S–H (calcium silicate hydrate is the main hydrate product and CH (calcium hydroxide. The morphology of hydration products changed with the increase of GO content. Furthermore, the results of XRD analyses showed that the diffraction peak intensity and the crystal grain size of CH (001, (100, (101, and (102 for GO samples increased considerably compared with the control sample. Based on the results, it can be understood that GO can modify the crystal surface of CH, leading to the formation of larger crystals.

  14. Toward Production From Gas Hydrates: Current Status, Assessment of Resources, and Simulation-Based Evaluationof Technology and Potential

    Energy Technology Data Exchange (ETDEWEB)

    Reagan, Matthew; Moridis, George J.; Collett, Timothy; Boswell, Ray; Kurihara, M.; Reagan, Matthew T.; Koh, Carolyn; Sloan, E. Dendy

    2008-02-12

    Gas hydrates are a vast energy resource with global distribution in the permafrost and in the oceans. Even if conservative estimates are considered and only a small fraction is recoverable, the sheer size of the resource is so large that it demands evaluation as a potential energy source. In this review paper, we discuss the distribution of natural gas hydrate accumulations, the status of the primary international R&D programs, and the remaining science and technological challenges facing commercialization of production. After a brief examination of gas hydrate accumulations that are well characterized and appear to be models for future development and gas production, we analyze the role of numerical simulation in the assessment of the hydrate production potential, identify the data needs for reliable predictions, evaluate the status of knowledge with regard to these needs, discuss knowledge gaps and their impact, and reach the conclusion that the numerical simulation capabilities are quite advanced and that the related gaps are either not significant or are being addressed. We review the current body of literature relevant to potential productivity from different types of gas hydrate deposits, and determine that there are consistent indications of a large production potential at high rates over long periods from a wide variety of hydrate deposits. Finally, we identify (a) features, conditions, geology and techniques that are desirable in potential production targets, (b) methods to maximize production, and (c) some of the conditions and characteristics that render certain gas hydrate deposits undesirable for production.

  15. Methane Production from Gas Hydrate Deposits through Injection of Supercritical CO2

    Directory of Open Access Journals (Sweden)

    Matthias Haeckel

    2012-06-01

    Full Text Available The recovery of natural gas from CH4-hydrate deposits in sub-marine and sub-permafrost environments through injection of CO2 is considered a suitable strategy towards emission-neutral energy production. This study shows that the injection of hot, supercritical CO2 is particularly promising. The addition of heat triggers the dissociation of CH4-hydrate while the CO2, once thermally equilibrated, reacts with the pore water and is retained in the reservoir as immobile CO2-hydrate. Furthermore, optimal reservoir conditions of pressure and temperature are constrained. Experiments were conducted in a high-pressure flow-through reactor at different sediment temperatures (2 °C, 8 °C, 10 °C and hydrostatic pressures (8 MPa, 13 MPa. The efficiency of both, CH4 production and CO2 retention is best at 8 °C, 13 MPa. Here, both CO2- and CH4-hydrate as well as mixed hydrates can form. At 2 °C, the production process was less effective due to congestion of transport pathways through the sediment by rapidly forming CO2-hydrate. In contrast, at 10 °C CH4 production suffered from local increases in permeability and fast breakthrough of the injection fluid, thereby confining the accessibility to the CH4 pool to only the most prominent fluid channels. Mass and volume balancing of the collected gas and fluid stream identified gas mobilization as equally important process parameter in addition to the rates of methane hydrate dissociation and hydrate conversion. Thus, the combination of heat supply and CO2 injection in one supercritical phase helps to overcome the mass transfer limitations usually observed in experiments with cold liquid or gaseous CO2.

  16. Simulating the gas hydrate production test at Mallik using the pilot scale pressure reservoir LARS

    Science.gov (United States)

    Heeschen, Katja; Spangenberg, Erik; Schicks, Judith M.; Priegnitz, Mike; Giese, Ronny; Luzi-Helbing, Manja

    2014-05-01

    LARS, the LArge Reservoir Simulator, allows for one of the few pilot scale simulations of gas hydrate formation and dissociation under controlled conditions with a high resolution sensor network to enable the detection of spatial variations. It was designed and built within the German project SUGAR (submarine gas hydrate reservoirs) for sediment samples with a diameter of 0.45 m and a length of 1.3 m. During the project, LARS already served for a number of experiments simulating the production of gas from hydrate-bearing sediments using thermal stimulation and/or depressurization. The latest test simulated the methane production test from gas hydrate-bearing sediments at the Mallik test site, Canada, in 2008 (Uddin et al., 2011). Thus, the starting conditions of 11.5 MPa and 11°C and environmental parameters were set to fit the Mallik test site. The experimental gas hydrate saturation of 90% of the total pore volume (70 l) was slightly higher than volumes found in gas hydrate-bearing formations in the field (70 - 80%). However, the resulting permeability of a few millidarcy was comparable. The depressurization driven gas production at Mallik was conducted in three steps at 7.0 MPa - 5.0 MPa - 4.2 MPa all of which were used in the laboratory experiments. In the lab the pressure was controlled using a back pressure regulator while the confining pressure was stable. All but one of the 12 temperature sensors showed a rapid decrease in temperature throughout the sediment sample, which accompanied the pressure changes as a result of gas hydrate dissociation. During step 1 and 2 they continued up to the point where gas hydrate stability was regained. The pressure decreases and gas hydrate dissociation led to highly variable two phase fluid flow throughout the duration of the simulated production test. The flow rates were measured continuously (gas) and discontinuously (liquid), respectively. Next to being discussed here, both rates were used to verify a model of gas

  17. General and gay-related racism experienced by Latino gay men.

    Science.gov (United States)

    Ibañez, Gladys E; Van Oss Marin, Barbara; Flores, Stephen A; Millett, Gregorio; Diaz, Rafael M

    2009-07-01

    Latino gay men report experiences of racial discrimination within and outside the gay community. This study focused on correlates of racism within general and gay contexts. Racism was assessed in a probability sample of 911 Latino gay men recruited from 3 U.S. cities. Factor analysis of the 10-item scale produced 2 factors: (a) General Racism Experiences, and (b) Racism Experiences in Gay Contexts. The scale and each factor showed adequate reliability and validity. Latino gay men with darker skin, more Indian features, more time in the United States, and low self-esteem reported more racism in both general and gay contexts. The authors examine the psychometric properties of a measure that assesses interpersonal racism among Latinos, report correlates of racism within a gay context, and provide an assessment tool for understanding the role of racism in the lives of Latino gay men.

  18. Hydration products of lime-metakaolin pastes at ambient temperature with ageing

    Energy Technology Data Exchange (ETDEWEB)

    Gameiro, A., E-mail: agameiro@lnec.pt [National Laboratory of Civil Engineering, Materials Department, Av. do Brasil, 101, 1700 Lisbon (Portugal); Santos Silva, A., E-mail: ssilva@lnec.pt [National Laboratory of Civil Engineering, Materials Department, Av. do Brasil, 101, 1700 Lisbon (Portugal); Veiga, R., E-mail: rveiga@lnec.pt [National Laboratory of Civil Engineering, Buildings Department, Av. do Brasil, 101, 1700 Lisbon (Portugal); Velosa, A., E-mail: avelosa@ua.pt [Department of Civil Engineering, Geobiotec, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

    2012-05-10

    Highlights: Black-Right-Pointing-Pointer We study the compounds formed in lime/MK blended pastes and their stability over time. Black-Right-Pointing-Pointer Different mixes of lime/MK pastes show different reaction kinetics during curing time, being the pozzolanic compounds formed directly proportional to the lime by MK replacement. Black-Right-Pointing-Pointer Some pozzolanic products are found to be unstable during the hydration reaction employed in our study. - Abstract: Mortars constituted of lime mixtures with pozzolanic additions have been extensively used in the past for the construction of historic and traditional buildings. This paper presents the results of blended pastes of lime and metakaolin (MK), namely compounds formed and their stability over time. This research is part of an extensive study aiming at the formulation of lime based mortars for restoration purposes. It has been shown for several years that MK has been applied in inorganic binders due to its capacity to react vigorously with calcium hydroxide (CH). In the presence of water originating a series of major hydrated phases, namely tetra calcium aluminate hydrate (C{sub 4}AH{sub 13}), calcium silicates hydrates (CSH) and calcium aluminium silicate hydrates (stratlingite - C{sub 2}ASH{sub 8}). Several blended pastes of lime and MK, with different substitution rates of lime by MK (wt%) were prepared and cured at a temperature of 20 Degree-Sign C and relative humidity RH > 95%. The phase composition of the formed hydrated phases was determined by X-ray diffraction (XRD) and simultaneous thermal analysis (TG-DTA). The obtained results showed that lime/MK pastes compositions displayed different reaction kinetics during curing time, being the pozzolanic products content directly proportional to the substitution rate of lime by MK. Also, a relationship between the increase stratlingite content and the MK substitution rate of lime by MK was found.

  19. Hydration Properties of Ground Granulated Blast-Furnace Slag (GGBS Under Different Hydration Environments

    Directory of Open Access Journals (Sweden)

    Shuhua LIU

    2017-02-01

    Full Text Available The hydration properties of various cementitious materials containing Ground Granulated Blast-furnace Slag (GGBS, two alkali-activated slag cements (AAS-1 and AAS-2 in which sodium silicate and sodium hydroxide act as alkaline activators respectively, supersulfated cement (SSC and slag Portland cement(PSC, are compared with ordinary Portland cement (OPC to investigate the effect of activating environment on the hydration properties in this study by determining the compressive strength of the pastes, the hydration heat of binders within 96 hours, and the hydration products at age of 28 days. The results show that C-S-H gels are the main hydrated products for all cementitious systems containing GGBS. Ca(OH2 is the hydration products of OPC and PSC paste. However, ettringite and gypsum crystals instead of Ca(OH2 are detected in SSC paste. Additionally, tobermorite, a crystalline C-S-H, and calcite are hydrated products in AAS-1. Tobermorite, cowlesite and calcite are hydrated products of AAS-2 as well. Based on strength results, AAS-1 paste exhibits the highest compressive strength followed by POC, PSC, SSC in order at all testing ages and AAS-2 give the lowest compressive strength except for the early age at 3 days, which is higher than SSC but still lower than PSC. From hydration heat analysis, alkalinity in the reaction solution is a vital factor influencing the initial hydration rate and the initial hydration rate from higher to lower is AAS-2, AAS-1, OPC, PSC and SSC. Although AAS possesses a faster reaction rate in the initial hours, cumulative hydration heat of AAS is comparably lower than that of OPC, but higher than those of PSC and SSC in turn, which indicates that the hydration heat of clinkers is much higher than that of slag.DOI: http://dx.doi.org/10.5755/j01.ms.23.1.14934

  20. Impact of pore-water freshening on clays and the compressibility of hydrate-bearing reservoirs during production

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Junbong [U.S. Geological Survey, Woods Hole, MA; Cao, Shuang [Louisiana State University, Baton Rouge, LA; Waite, William [U.S. Geological Survey, Woods Hole, MA; Jung, Jongwon [Chungbuk National University, Cheongju-si, Chungbuk, South Korea

    2017-06-25

    Gas production efficiency from natural hydrate-bearing sediments depends in part on geotechnical properties of fine-grained materials, which are ubiquitous even in sandy hydrate-bearing sediments. The responses of fine-grained material to pore fluid chemistry changes due to freshening during hydrate dissociation could alter critical sediment characteristics during gas production activities. We investigate the electrical sensitivity of fine grains to pore fluid freshening and the implications of freshening on sediment compression and recompression parameters.

  1. Numerical studies of gas production from several CH4 hydrate zones at the Mallik site, Mackenzie Delta, Canada

    Science.gov (United States)

    Moridis, G.J.; Collett, T.S.; Dallimore, S.R.; Satoh, T.; Hancock, S.; Weatherill, B.

    2004-01-01

    The Mallik site represents an onshore permafrost-associated gas hydrate accumulation in the Mackenzie Delta, Northwest Territories, Canada. A gas hydrate research well was drilled at the site in 1998. The objective of this study is the analysis of various gas production scenarios from five methane hydrate-bearing zones at the Mallik site. In Zone #1, numerical simulations using the EOSHYDR2 model indicated that gas production from hydrates at the Mallik site was possible by depressurizing a thin free gas zone at the base of the hydrate stability field. Horizontal wells appeared to have a slight advantage over vertical wells, while multiwell systems involving a combination of depressurization and thermal stimulation offered superior performance, especially when a hot noncondensible gas was injected. Zone #2, which involved a gas hydrate layer with an underlying aquifer, could yield significant amounts of gas originating entirely from gas hydrates, the volumes of which increased with the production rate. However, large amounts of water were also produced. Zones #3, #4 and #5 were lithologically isolated gas hydrate-bearing deposits with no underlying zones of mobile gas or water. In these zones, thermal stimulation by circulating hot water in the well was used to induce dissociation. Sensitivity studies indicated that the methane release from the hydrate accumulations increased with the gas hydrate saturation, the initial formation temperature, the temperature of the circulating water in the well, and the formation thermal conductivity. Methane production appears to be less sensitive to the specific heat of the rock and of the hydrate, and to the permeability of the formation. ?? 2004 Published by Elsevier B.V.

  2. Methane Hydrates: Chapter 8

    Science.gov (United States)

    Boswell, Ray; Yamamoto, Koji; Lee, Sung-Rock; Collett, Timothy S.; Kumar, Pushpendra; Dallimore, Scott

    2008-01-01

    Gas hydrate is a solid, naturally occurring substance consisting predominantly of methane gas and water. Recent scientific drilling programs in Japan, Canada, the United States, Korea and India have demonstrated that gas hydrate occurs broadly and in a variety of forms in shallow sediments of the outer continental shelves and in Arctic regions. Field, laboratory and numerical modelling studies conducted to date indicate that gas can be extracted from gas hydrates with existing production technologies, particularly for those deposits in which the gas hydrate exists as pore-filling grains at high saturation in sand-rich reservoirs. A series of regional resource assessments indicate that substantial volumes of gas hydrate likely exist in sand-rich deposits. Recent field programs in Japan, Canada and in the United States have demonstrated the technical viability of methane extraction from gas-hydrate-bearing sand reservoirs and have investigated a range of potential production scenarios. At present, basic reservoir depressurisation shows the greatest promise and can be conducted using primarily standard industry equipment and procedures. Depressurisation is expected to be the foundation of future production systems; additional processes, such as thermal stimulation, mechanical stimulation and chemical injection, will likely also be integrated as dictated by local geological and other conditions. An innovative carbon dioxide and methane swapping technology is also being studied as a method to produce gas from select gas hydrate deposits. In addition, substantial additional volumes of gas hydrate have been found in dense arrays of grain-displacing veins and nodules in fine-grained, clay-dominated sediments; however, to date, no field tests, and very limited numerical modelling, have been conducted with regard to the production potential of such accumulations. Work remains to further refine: (1) the marine resource volumes within potential accumulations that can be

  3. Geomechanical response of permafrost-associated hydrate deposits to depressurization-induced gas production

    Science.gov (United States)

    Rutqvist, J.; Moridis, G.J.; Grover, T.; Collett, T.

    2009-01-01

    In this simulation study, we analyzed the geomechanical response during depressurization production from two known hydrate-bearing permafrost deposits: the Mallik (Northwest Territories, Canada) deposit and Mount Elbert (Alaska, USA) deposit. Gas was produced from these deposits at constant pressure using horizontal wells placed at the top of a hydrate layer (HL), located at a depth of about 900??m at the Mallik site and 600??m at the Mount Elbert site. The simulation results show that general thermodynamic and geomechanical responses are similar for the two sites, but with substantially higher production and more intensive geomechanical responses at the deeper Mallik deposit. The depressurization-induced dissociation begins at the well bore and then spreads laterally, mainly along the top of the HL. The depressurization results in an increased shear stress within the body of the receding hydrate and causes a vertical compaction of the reservoir. However, its effects are partially mitigated by the relatively stiff permafrost overburden, and compaction of the HL is limited to less than 0.4%. The increased shear stress may lead to shear failure in the hydrate-free zone bounded by the HL overburden and the downward-receding upper dissociation interface. This zone undergoes complete hydrate dissociation, and the cohesive strength of the sediment is low. We determined that the likelihood of shear failure depends on the initial stress state as well as on the geomechanical properties of the reservoir. The Poisson's ratio of the hydrate-bearing formation is a particularly important parameter that determines whether the evolution of the reservoir stresses will increase or decrease the likelihood of shear failure.

  4. Methane hydrate dissociation using inverted five-spot water flooding method in cubic hydrate simulator

    International Nuclear Information System (INIS)

    Li, Gang; Li, Xiao-Sen; Li, Bo; Wang, Yi

    2014-01-01

    The combination forms of the hydrate dissociation methods in different well systems are divided into 6 main patterns. Dissociation processes of methane hydrate in porous media using the inverted five-spot water flooding method (Pattern 4) are investigated by the experimental observation and numerical simulation. In situ methane hydrate is synthesized in the Cubic Hydrate Simulator (CHS), a 5.832-L cubic reactor. A center vertical well is used as the hot water injection well, while the four vertical wells at the corner are the gas and water production wells. The gas production begins simultaneously with the hot water injection, while after approximately 20 min of compression, the water begins to be produced. One of the common characteristics of the inverted five-spot water flooding method is that both the gas and water production rates decrease with the reduction of the hydrate dissociation rate. The evaluation of the energy efficiency ratio might indicate the inverted five-spot water flooding as a promising gas producing method from the hydrate reservoir. - Highlights: • A three-dimensional 5.8-L cubic pressure vessel is developed. • Gas production of hydrate using inverted five-spot flooding method is studied. • Water/gas production rate and energy efficiency ratio are evaluated. • Temperature distributions of numerical simulation and experiment agree well. • Hydrate dissociation process is a moving boundary problem in this study

  5. Religiusitas pada Gay (Studi Fenomenologis pada Gay yang Beragama Islam)

    OpenAIRE

    Ariansyah

    2015-01-01

    Gay still be controversial and viewed negatively in Indonesian society. Most assume that it is impossible for gay to have religiosity. But in the reality, gays also have religiosity. This study aims to determine how the religiosity that is owned by a gay. In addition to knowing religiosity, this study also aims to determine the factors that led to participants being gay. This study used a qualitative phenomenological method. Participants in this study consists of 3 people. M...

  6. Decomposition of methane hydrate for hydrogen production using microwave and radio frequency in-liquid plasma methods

    International Nuclear Information System (INIS)

    Rahim, Ismail; Nomura, Shinfuku; Mukasa, Shinobu; Toyota, Hiromichi

    2015-01-01

    This research involves two in-liquid plasma methods of methane hydrate decomposition, one using radio frequency wave (RF) irradiation and the other microwave radiation (MW). The ultimate goal of this research is to develop a practical process for decomposition of methane hydrate directly at the subsea site for fuel gas production. The mechanism for methane hydrate decomposition begins with the dissociation process of methane hydrate formed by CH_4 and water. The process continues with the simultaneously occurring steam methane reforming process and methane cracking reaction, during which the methane hydrate is decomposed releasing CH_4 into H_2, CO and other by-products. It was found that methane hydrate can be decomposed with a faster rate of CH_4 release using microwave irradiation over that using radio frequency irradiation. However, the radio frequency plasma method produces hydrogen with a purity of 63.1% and a CH conversion ratio of 99.1%, which is higher than using microwave plasma method which produces hydrogen with a purity of 42.1% and CH_4 conversion ratio of 85.5%. - Highlights: • The decomposition of methane hydrate is proposed using plasma in-liquid method. • Synthetic methane hydrate is used as the sample for decomposition in plasma. • Hydrogen can be produced from decomposition of methane hydrate. • Hydrogen purity is higher when using radio frequency stimulation.

  7. Vowel production, speech-motor control, and phonological encoding in people who are lesbian, bisexual, or gay, and people who are not

    Science.gov (United States)

    Munson, Benjamin; Deboe, Nancy

    2003-10-01

    A recent study (Pierrehumbert, Bent, Munson, and Bailey, submitted) found differences in vowel production between people who are lesbian, bisexual, or gay (LBG) and people who are not. The specific differences (more fronted /u/ and /a/ in the non-LB women; an overall more-contracted vowel space in the non-gay men) were not amenable to an interpretation based on simple group differences in vocal-tract geometry. Rather, they suggested that differences were either due to group differences in some other skill, such as motor control or phonological encoding, or learned. This paper expands on this research by examining vowel production, speech-motor control (measured by diadochokinetic rates), and phonological encoding (measured by error rates in a tongue-twister task) in people who are LBG and people who are not. Analyses focus on whether the findings of Pierrehumbert et al. (submitted) are replicable, and whether group differences in vowel production are related to group differences in speech-motor control or phonological encoding. To date, 20 LB women, 20 non-LB women, 7 gay men, and 7 non-gay men have participated. Preliminary analyses suggest that there are no group differences in speech motor control or phonological encoding, suggesting that the earlier findings of Pierrehumbert et al. reflected learned behaviors.

  8. Introduction of the 2007-2008 JOGMEC/NRCan/Aurora Mallik Gas Hydrate Production Research Program, NWT, Canada

    Science.gov (United States)

    Yamamoto, K.; Dallimore, S. R.; Numasawa, M.; Yasuda, M.; Fujii, T.; Fujii, K.; Wright, J.; Nixon, F.

    2007-12-01

    Japan Oil, Gas and Metals National Corporation (JOGMEC) and Natural Resource Canada (NRCan) have embarked on a new research program to study the production potential of gas hydrates. The program is being carried out at the Mallik gas hydrate field in the Mackenzie Delta, a location where two previous scientific investigations have been carried in 1998 and 2002. In the 2002 program that was undertaken by seven partners from five countries, 468m3 of gas flow was measured during 124 hours of thermal stimulation using hot warm fluid. Small-scale pressure drawdown tests were also carried out using Schlumberger's Modular Dynamics Tester (MDT) wireline tool, gas flow was observed and the inferred formation permeabilities suggested the possible effectiveness of the simple depressurization method. While the testing undertaken in 2002 can be cited as the first well constrained gas production from a gas hydrate deposit, the results fell short of that required to fully calibrate reservoir simulation models or indeed establish the technical viability of long term production from gas hydrates. The objectives of the current JOGMEC/NRCan/Aurora Mallik production research program are to undertake longer term production testing to further constrain the scientific unknowns and to demonstrate the technical feasibility of sustained gas hydrate production using the depressurization method. A key priority is to accurately measure water and gas production using state-of-art production technologies. The primary production test well was established during the 2007 field season with the re-entry and deepening of JAPEX/JNOC/GSC Mallik 2L-38 well, originally drilled in 1998. Production testing was carried out in April of 2007 under a relatively low drawdown pressure condition. Flow of methane gas was measured from a 12m perforated interval of gas-hydrate-saturated sands from 1093 to 1105m. The results establish the potential of the depressurization method and provide a basis for future

  9. Petrophysical Characterization and Reservoir Simulator for Methane Gas Production from Gulf of Mexico Hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Kishore Mohanty; Bill Cook; Mustafa Hakimuddin; Ramanan Pitchumani; Damiola Ogunlana; Jon Burger; John Shillinglaw

    2006-06-30

    Gas hydrates are crystalline, ice-like compounds of gas and water molecules that are formed under certain thermodynamic conditions. Hydrate deposits occur naturally within ocean sediments just below the sea floor at temperatures and pressures existing below about 500 meters water depth. Gas hydrate is also stable in conjunction with the permafrost in the Arctic. Most marine gas hydrate is formed of microbially generated gas. It binds huge amounts of methane into the sediments. Estimates of the amounts of methane sequestered in gas hydrates worldwide are speculative and range from about 100,000 to 270,000,000 trillion cubic feet (modified from Kvenvolden, 1993). Gas hydrate is one of the fossil fuel resources that is yet untapped, but may play a major role in meeting the energy challenge of this century. In this project novel techniques were developed to form and dissociate methane hydrates in porous media, to measure acoustic properties and CT properties during hydrate dissociation in the presence of a porous medium. Hydrate depressurization experiments in cores were simulated with the use of TOUGHFx/HYDRATE simulator. Input/output software was developed to simulate variable pressure boundary condition and improve the ease of use of the simulator. A series of simulations needed to be run to mimic the variable pressure condition at the production well. The experiments can be matched qualitatively by the hydrate simulator. The temperature of the core falls during hydrate dissociation; the temperature drop is higher if the fluid withdrawal rate is higher. The pressure and temperature gradients are small within the core. The sodium iodide concentration affects the dissociation pressure and rate. This procedure and data will be useful in designing future hydrate studies.

  10. Hydrates on tap: scientists say natural gas hydrates may be tough nut to crack

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, J.

    2001-12-01

    Gas hydrates are methane molecules trapped in cages of water molecules, yielding a substance with a slushy, sherbet-like consistency. Drilling for hydrates is similar to conventional oil and gas drilling, however, the secret to economic production still remains hidden. Hydrates exist in abundance in such places as deep ocean floor and below ground in some polar regions. The real challenge lies in producing gas from this resource, inasmuch as there is no existing technology for production of gas specifically from methane hydrates. This paper describes an international research program, involving a five-country partnership to spud the first of three wells into the permafrost of the Mackenzie River Delta in the Northwest Territories. The project, worth about $15 million, has brought together public funding and expertise from Japan, Germany, India as well as the Canadian and US Geological Surveys and the US Dept. of Energy in an effort to gain information on the production response of gas hydrates. The operator of the project is Japan Petroleum Exploration Company of Canada, a subsidiary of Japan National Oil Corporation. Since Japan is poor in domestic hydrocarbon resources, but is surrounded by deep water that contains potential for gas hydrates, Japan has a great deal riding on the success of this project. Germany and the United States are also very much interested. Current thinking is that gas is in contact with the hydrates and that it should be possible to develop a free gas reservoir as if it were a conventional deposit. As the free gas is drawn off, the pressure is reduced on the hydrates in contact with it , the hydrates dissociate from the gas and replenish the conventional reservoir. So far this is still only a theory, but it appears to be a sensible approach to hydrate production. 1 photo.

  11. Hydraulic and Mechanical Effects from Gas Hydrate Conversion and Secondary Gas Hydrate Formation during Injection of CO2 into CH4-Hydrate-Bearing Sediments

    Science.gov (United States)

    Bigalke, N.; Deusner, C.; Kossel, E.; Schicks, J. M.; Spangenberg, E.; Priegnitz, M.; Heeschen, K. U.; Abendroth, S.; Thaler, J.; Haeckel, M.

    2014-12-01

    The injection of CO2 into CH4-hydrate-bearing sediments has the potential to drive natural gas production and simultaneously sequester CO2 by hydrate conversion. The process aims at maintaining the in situ hydrate saturation and structure and causing limited impact on soil hydraulic properties and geomechanical stability. However, to increase hydrate conversion yields and rates it must potentially be assisted by thermal stimulation or depressurization. Further, secondary formation of CO2-rich hydrates from pore water and injected CO2 enhances hydrate conversion and CH4 production yields [1]. Technical stimulation and secondary hydrate formation add significant complexity to the bulk conversion process resulting in spatial and temporal effects on hydraulic and geomechanical properties that cannot be predicted by current reservoir simulation codes. In a combined experimental and numerical approach, it is our objective to elucidate both hydraulic and mechanical effects of CO2 injection and CH4-CO2-hydrate conversion in CH4-hydrate bearing soils. For the experimental approach we used various high-pressure flow-through systems equipped with different online and in situ monitoring tools (e.g. Raman microscopy, MRI and ERT). One particular focus was the design of triaxial cell experimental systems, which enable us to study sample behavior even during large deformations and particle flow. We present results from various flow-through high-pressure experimental studies on different scales, which indicate that hydraulic and geomechanical properties of hydrate-bearing sediments are drastically altered during and after injection of CO2. We discuss the results in light of the competing processes of hydrate dissociation, hydrate conversion and secondary hydrate formation. Our results will also contribute to the understanding of effects of temperature and pressure changes leading to dissociation of gas hydrates in ocean and permafrost systems. [1] Deusner C, Bigalke N, Kossel E

  12. Micro-structural characterization of the hydration products of bauxite-calcination-method red mud-coal gangue based cementitious materials

    International Nuclear Information System (INIS)

    Liu, Xiaoming; Zhang, Na; Yao, Yuan; Sun, Henghu; Feng, Huan

    2013-01-01

    Highlights: • Al IV and Al VI both exist in the hydration products. • Increase of Ca/Si ratio promotes the conversion from [AlO 4 ] to [AlO 6 ]. • Polymerization degree of [SiO 4 ] in the hydration products declines. -- Abstract: In this research, the micro-structural characterization of the hydration products of red mud-coal gangue based cementitious materials has been investigated through SEM-EDS, 27 Al MAS NMR and 29 Si MAS NMR techniques, in which the used red mud was derived from the bauxite calcination method. The results show that the red mud-coal gangue based cementitious materials mainly form fibrous C-A-S-H gel, needle-shaped/rod-like AFt in the early hydration period. With increasing of the hydration period, densification of the pastes were promoted resulting in the development of strength. EDS analysis shows that with the Ca/Si of red mud-coal gangue based cementitious materials increases, the average Ca/Si and Ca/(Si + Al) atomic ratio of C-A-S-H gel increases, while the average Al/Si atomic ratio of C-A-S-H gel decreases. MAS NMR analysis reveals that Al in the hydration products of red mud-coal gangue based cementitious materials exists in the forms of Al IV and Al VI , but mainly in the form of Al VI . Increasing the Ca/Si ratio of raw material promotes the conversion of [AlO 4 ] to [AlO 6 ] and inhibits the combination between [AlO 4 ] and [SiO 4 ] to form C-A-S-H gel. Meanwhile, the polymerization degree of [SiO 4 ] in the hydration products declines

  13. Formation rate of natural gas hydrate

    Energy Technology Data Exchange (ETDEWEB)

    Mork, Marit

    2002-07-01

    The rate of methane hydrate and natural gas hydrate formation was measured in a 9.5 litre stirred tank reactor of standard design. The experiments were performed to better understand the performance and scale-up of a reactor for continuous production of natural gas hydrates. The hydrate formation rate was measured at steady-state conditions at pressures between 70 and 90 bar and temperatures between 7 and 15 deg C. Between 44 and 56 % of the gas continuously supplied to the reactor was converted to hydrate. The experimental results show that the rate of hydrate formation is strongly influenced by gas injection rate and pressure. The effect of stirring rate is less significant and subcooling has no observable effect on the formation rate. Hydrate crystal concentration and gas composition do not influence the hydrate formation rate. Observations of produced hydrate crystals indicate that the crystals are elongated, about 5 micron in diameter and 10 micron long. Analysis of the results shows that the rate of hydrate formation is dominated by gas-liquid mass transfer. A mass transfer model, the bubble-to-crystal model, was developed for the hydrate formation rate in a continuous stirred tank reactor, given in terms of concentration driving force and an overall mass transfer coefficient. The driving force is the difference between the gas concentration at the gas-liquid interface and at the hydrate crystal surface. These concentrations correspond to the solubility of gas in water at experimental temperature and pressure and the solubility of gas at hydrate equilibrium temperature and experimental pressure, respectively. The overall mass transfer coefficient is expressed in terms of superficial gas velocity and impeller power consumption, parameters commonly used in study of stirred tank reactors. Experiments and modeling show that the stirred tank reactor has a considerable potential for increased production capacity. However, at higher hydrate production rates the

  14. Hydro-geomechanical behaviour of gas-hydrate bearing soils during gas production through depressurization and CO2 injection

    Science.gov (United States)

    Deusner, C.; Gupta, S.; Kossel, E.; Bigalke, N.; Haeckel, M.

    2015-12-01

    Results from recent field trials suggest that natural gas could be produced from marine gas hydrate reservoirs at compatible yields and rates. It appears, from a current perspective, that gas production would essentially be based on depressurization and, when facing suitable conditions, be assisted by local thermal stimulation or gas hydrate conversion after injection of CO2-rich fluids. Both field trials, onshore in the Alaska permafrost and in the Nankai Trough offshore Japan, were accompanied by different technical issues, the most striking problems resulting from un-predicted geomechanical behaviour, sediment destabilization and catastrophic sand production. So far, there is a lack of experimental data which could help to understand relevant mechanisms and triggers for potential soil failure in gas hydrate production, to guide model development for simulation of soil behaviour in large-scale production, and to identify processes which drive or, further, mitigate sand production. We use high-pressure flow-through systems in combination with different online and in situ monitoring tools (e.g. Raman microscopy, MRI) to simulate relevant gas hydrate production scenarios. Key components for soil mechanical studies are triaxial systems with ERT (Electric resistivity tomography) and high-resolution local strain analysis. Sand production control and management is studied in a novel hollow-cylinder-type triaxial setup with a miniaturized borehole which allows fluid and particle transport at different fluid injection and flow conditions. Further, the development of a large-scale high-pressure flow-through triaxial test system equipped with μ-CT is ongoing. We will present results from high-pressure flow-through experiments on gas production through depressurization and injection of CO2-rich fluids. Experimental data are used to develop and parametrize numerical models which can simulate coupled process dynamics during gas-hydrate formation and gas production.

  15. Micro-structural characterization of the hydration products of bauxite-calcination-method red mud-coal gangue based cementitious materials

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaoming [State Key Laboratory of Advanced Metallurgy, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhang, Na [Green Construction Materials and Circulation Economy Center, Architectural Design and Research Institute of Tsinghua University Co., Ltd., Beijing 100084 (China); Yao, Yuan, E-mail: yuanyaocas@163.com [School of Engineering and Computer Science, University of the Pacific, Stockton, CA 95211 (United States); Sun, Henghu; Feng, Huan [School of Engineering and Computer Science, University of the Pacific, Stockton, CA 95211 (United States)

    2013-11-15

    Highlights: • Al{sup IV} and Al{sup VI} both exist in the hydration products. • Increase of Ca/Si ratio promotes the conversion from [AlO{sub 4}] to [AlO{sub 6}]. • Polymerization degree of [SiO{sub 4}] in the hydration products declines. -- Abstract: In this research, the micro-structural characterization of the hydration products of red mud-coal gangue based cementitious materials has been investigated through SEM-EDS, {sup 27}Al MAS NMR and {sup 29}Si MAS NMR techniques, in which the used red mud was derived from the bauxite calcination method. The results show that the red mud-coal gangue based cementitious materials mainly form fibrous C-A-S-H gel, needle-shaped/rod-like AFt in the early hydration period. With increasing of the hydration period, densification of the pastes were promoted resulting in the development of strength. EDS analysis shows that with the Ca/Si of red mud-coal gangue based cementitious materials increases, the average Ca/Si and Ca/(Si + Al) atomic ratio of C-A-S-H gel increases, while the average Al/Si atomic ratio of C-A-S-H gel decreases. MAS NMR analysis reveals that Al in the hydration products of red mud-coal gangue based cementitious materials exists in the forms of Al{sup IV} and Al{sup VI}, but mainly in the form of Al{sup VI}. Increasing the Ca/Si ratio of raw material promotes the conversion of [AlO{sub 4}] to [AlO{sub 6}] and inhibits the combination between [AlO{sub 4}] and [SiO{sub 4}] to form C-A-S-H gel. Meanwhile, the polymerization degree of [SiO{sub 4}] in the hydration products declines.

  16. Effects of gay identity, gender and explicitness of advertising imagery on gay responses to advertising.

    Science.gov (United States)

    Oakenfull, Gillian

    2007-01-01

    The present research draws from literature relating to gay identity in psychology and sociology and feminist theory to consider the effect of gay identity and gender on gays' and lesbians' attitudes toward various types of advertising content that are most commonly used to target gay consumers. As such, this study empirically tests whether gay males' and lesbians' responses to gay-oriented advertising content are moderated by individual characteristics: (1) the degree to which they identify as gay, and (2) their gender, and by the explicitness and gender of the gay-oriented advertising imagery.

  17. Lightweight Approaches to Natural Gas Hydrate Exploration & Production

    Science.gov (United States)

    Max, M. D.; Johnson, A. H.

    2017-12-01

    Lower-cost approaches to drilling and reservoir utilization are made possible by adapting both emerging and new technology to the unique, low risk NGH natural gas resource. We have focused on drilling, wellbore lining technology, and reservoir management with an emphasis on long-term sand control and adaptive mechanical stability during NGH conversion to its constituent gas and water. In addition, we suggest that there are opportunities for management of both the gas and water with respect to maintaining desired thermal conditions. Some of the unique aspects of NGH deposits allow for new, more efficient technology to be applied to development, particularly in drilling. While NGH-bearing sands are in deepwater, they are confined to depths beneath the seafloor of 1.2 kilometers or less. As a result, they will not be significantly above hydrostatic pressure, and temperatures will be less than 30 oC. Drilling will be through semi-consolidated sediment without liquid hydrocarbons. These characteristics mean that high capability drillships are not needed. What is needed is a new perspective about drilling and producing NGH. Drilling from the seafloor will resolve the high-pressure differential between a wellhead on the sea surface in a vessel and reservoir to about the hydrostatic pressure difference between the seafloor and, at most, the base of the GHSZ. Although NGH production will begin using "off-the-shelf" technology, innovation will lead to new technology that will bring down costs and increase efficiency in the same way that led to the shale breakthrough. Commercial success is possible if consideration is given to what is actually needed to produce NGH in a safe and environmentally manner. Max, M.D. 2017. Wellbore Lining for Natural Gas Hydrate. U.S. Patent Application US15644947 Max, M.D. & Johnson, A.H. 2017. E&P Cost Reduction Opportunities for Natural Gas Hydrate. OilPro. . Max, M.D. & Johnson, A.H. 2016. Exploration and Production of Oceanic Natural Gas

  18. Historical methane hydrate project review

    Science.gov (United States)

    Collett, Timothy; Bahk, Jang-Jun; Frye, Matt; Goldberg, Dave; Husebo, Jarle; Koh, Carolyn; Malone, Mitch; Shipp, Craig; Torres, Marta

    2013-01-01

    In 1995, U.S. Geological Survey made the first systematic assessment of the volume of natural gas stored in the hydrate accumulations of the United States. That study, along with numerous other studies, has shown that the amount of gas stored as methane hydrates in the world greatly exceeds the volume of known conventional gas resources. However, gas hydrates represent both a scientific and technical challenge and much remains to be learned about their characteristics and occurrence in nature. Methane hydrate research in recent years has mostly focused on: (1) documenting the geologic parameters that control the occurrence and stability of gas hydrates in nature, (2) assessing the volume of natural gas stored within various gas hydrate accumulations, (3) analyzing the production response and characteristics of methane hydrates, (4) identifying and predicting natural and induced environmental and climate impacts of natural gas hydrates, and (5) analyzing the effects of methane hydrate on drilling safety.Methane hydrates are naturally occurring crystalline substances composed of water and gas, in which a solid water-­‐lattice holds gas molecules in a cage-­‐like structure. The gas and water becomes a solid under specific temperature and pressure conditions within the Earth, called the hydrate stability zone. Other factors that control the presence of methane hydrate in nature include the source of the gas included within the hydrates, the physical and chemical controls on the migration of gas with a sedimentary basin containing methane hydrates, the availability of the water also included in the hydrate structure, and the presence of a suitable host sediment or “reservoir”. The geologic controls on the occurrence of gas hydrates have become collectively known as the “methane hydrate petroleum system”, which has become the focus of numerous hydrate research programs.Recognizing the importance of methane hydrate research and the need for a coordinated

  19. Tswanarising global gayness: the 'unAfrican' argument, Western gay media imagery, local responses and gay culture in Botswana.

    Science.gov (United States)

    McAllister, John

    2013-01-01

    This paper is a strategic intervention in the debate over the value of globalised gay identity for emerging sexual minority communities in the South. Focusing on self-identifying gay men in Botswana using semi-structured interviews, it explores their views of what characterises 'modern gay culture' and relates these to international media clichés of a glamorous, stylish, hedonistic gayness. I argue that identifying with what is so visibly a Western image of gayness exposes sexual minority communities to the most dangerous of the justifications for homophobia in Africa, the argument that sexual dissidence is a neo-colonial conspiracy to subvert 'African values'. The 'unAfrican' argument has to be taken very seriously, not only because it taps into the intense, conflicted emotions at the heart of the post-colonial condition, but also because it contains an undeniable germ of truth. This poses a dilemma, since global gay discourses, including the media clichés, are an important source of inspiration for African sexual minorities. A communication activism strategy is proposed to undermine the unAfrican argument by cultivating and asserting the 'tswanarisation' of gay culture in Botswana that is already taking place. A similar strategy may also be effective in other African societies.

  20. Impacts of Hydrate Distribution on the Hydro-Thermo-Mechanical Properties of Hydrate-Bearing Sediments

    Science.gov (United States)

    Dai, S.; Seol, Y.

    2015-12-01

    In general, hydrate makes the sediments hydraulically less conductive, thermally more conductive, and mechanically stronger; yet the dependency of these physical properties on hydrate saturation varies with hydrate distribution and morphology. Hydrate distribution in sediments may cause the bulk physical properties of their host sediments varying several orders of magnitude even with the same amount of hydrate. In natural sediments, hydrate morphology is inherently governed by the burial depth and the grain size of the host sediments. Compare with patchy hydrate, uniformly distributed hydrate is more destructive to fluid flow, yet leads to higher gas and water permeability during hydrate dissociation due to the easiness of forming percolation paths. Water and hydrate have similar thermal conductivity values; the bulk thermal conductivity of hydrate-bearing sediments depends critically on gas-phase saturation. 60% of gas saturation may result in evident thermal conductivity drop and hinder further gas production. Sediments with patchy hydrate yield lower stiffness than that with cementing hydrate but higher stiffness than that with pore filling and loading bearing hydrate. Besides hydrate distribution, the stress state and loading history also play an important role in the mechanical behavior of hydrate-bearing sediments.

  1. Assessment of Gas Production Potential from Hydrate Reservoir in Qilian Mountain Permafrost Using Five-Spot Horizontal Well System

    Directory of Open Access Journals (Sweden)

    Yun-Pei Liang

    2015-09-01

    Full Text Available The main purpose of this study is to investigate the production behaviors of gas hydrate at site DK-2 in the Qilian Mountain permafrost using the novel five-spot well (5S system by means of numerical simulation. The whole system is composed of several identical units, and each single unit consists of one injection well and four production wells. All the wells are placed horizontally in the hydrate deposit. The combination method of depressurization and thermal stimulation is employed for hydrate dissociation in the system. Simulation results show that favorable gas production and hydrate dissociation rates, gas-to-water ratio, and energy ratio can be acquired using this kind of multi-well system under suitable heat injection and depressurization driving forces, and the water production rate is manageable in the entire production process under current technology. In addition, another two kinds of two-spot well (2S systems have also been employed for comparison. It is found that the 5S system will be more commercially profitable than the 2S configurations for gas production under the same operation conditions. Sensitivity analysis indicates that the gas production performance is dependent on the heat injection rate and the well spacing of the 5S system.

  2. "Straight-acting gays": the relationship between masculine consciousness, anti-effeminacy, and negative gay identity.

    Science.gov (United States)

    Sánchez, Francisco J; Vilain, Eric

    2012-02-01

    Some gay men are preoccupied with traditional notions of masculinity and express negative feelings towards effeminate behavior in gay men. Various scholars have speculated that such attitudes by gay men reflect internalized negative feelings about being gay. Thus, we sought to assess the importance of masculinity among gay men, to compare their ideal versus perceived masculinity-femininity, to ask how gay men assess masculinity, and to test whether masculine consciousness and anti-effeminacy could predict negative feelings about being gay. Results from an online survey of 751 gay men in the United States (MAge=32.64 years, SD=11.94) showed that the majority rated masculinity for themselves and in a same-sex partner as important, and they ideally wished that their behavior was more masculine (Cohen's d=.42) and less feminine (d=.42) than they perceived it to be. Furthermore, one's behavior was more important than how one looks when assessing masculinity. A multiple regression analysis showed that the degree to which they were preoccupied with masculinity and expressed anti-effeminacy accounted for 30% of the variance in negative feelings about being gay. These finding further support the idea that masculinity is an important construct for gay men and that masculine consciousness and anti-effeminacy are related to negative feelings about being gay.

  3. Comradeship of Cock? Gay porn and the entrepreneurial voyeur

    OpenAIRE

    Maddison, Stephen

    2017-01-01

    Thirty years of academic and critical scholarship on the subject of gay porn have born witness to significant changes not only in the kinds of porn produced for, and watched by, gay men, but in the modes of production and distribution of that porn, and the legal, economic and social contexts in which it has been made, sold/shared, and watched. Those thirty years have also seen a huge shift in the cultural and political position of gay men, especially in the US and UK, and other apparently ‘ad...

  4. In vitro methods for evaluating skin hydration under diapers and incontinence products.

    Science.gov (United States)

    Tate, M L; Wright, A S

    2017-11-01

    Excessive skin hydration from wearing wet undergarments, such as infant diapers and adult incontinence products, has been historically problematic. Skin damage occurs from wetness (urine) and limited product breathability. Evaporative water loss has been measured on adult arms (armband method) or infant torsos (on-baby method), after wearing a saline-insulted diaper product. The current study developed a reliable in vitro method of evaluating diaper and incontinence products for improvements in skin dryness. A simulated skin substrate was applied to a heated mechanical arm or baby torso. A disposable diaper or incontinence product was wrapped around the arm or baby torso, and loaded with saline. Hydration of the simulated skin was measured by evaporimetry and compared with clinical data from adult armband evaluations. The heated mechanical arm and baby torso accurately distinguished products for skin dryness. Eight diaper products were evaluated and compared to human test results. The torso in vitro and mechanical arm evaluations demonstrated strong correlations to human epidermal water loss evaluations, with repeatable results. Additionally, the bench test has been used for adult incontinence products, and it proved to differentiate those products as well as infant products. A rapid and reliable means of evaluation has been developed, and it is predictive of human subject testing. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Hydration products and mechanical properties of hydroceramics solidified waste for simulated Non-alpha low and intermediate level radioactive wastes

    International Nuclear Information System (INIS)

    Wang Jin; Hong Ming; Wang Junxia; Li Yuxiang; Teng Yuancheng; Wu Xiuling

    2011-01-01

    In this paper, simulated non-alpha low and intermediate level radioactive wastes was handled as curing object and that of 'alkali-slag-coal fly ash-metakaolin' hydroceramics waste forms were prepared by hydrothermal synthesis method. The hydration products were analyzed by X ray diffraction. The composition of hydrates and the compressive strength of waste forms were determined and measured. The results indicate that the main crystalline phase of hydration products were analcite when the temperature was 150 to 180 degree C and the salt content ratio was 0.10 to 0.30. Analcite diffraction peaks in hydration products is increasing when the temperature was raised and the reaction time prolonged. Strength test results show that the solidified waste forms have superior compressive strength. The compressive strength gradually decreased with the increase in salt content ratio in waste forms. (authors)

  6. Hydration interactions and stability of soluble microbial products in aqueous solutions.

    Science.gov (United States)

    Wang, Ling-Ling; Wang, Long-Fei; Ye, Xiao-Dong; Yu, Han-Qing

    2013-10-01

    Soluble microbial products (SMP) are organic compounds excreted by microorganisms in their metabolism and decay and the main constituents in effluent from biological wastewater treatment systems. They also have an important contribution to the dissolved organic matters in natural aqueous systems. So far the interactions between SMP colloids have not been well explored. In this work, the interactions between SMP colloids in water and salt solutions were studied by using a combination of static and dynamic light scattering, Fourier transform infrared spectra, Zeta potential and acid-base titration techniques. The second osmotic virial coefficient had a larger value in a 750-mM salt solution than that in a 50-mM solution, indicating that repulsion between SMP colloids increased with an increase in salt concentration, which is contrary with the classic Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory. Such a repulsion was attributed to water structuring and enhanced by the accumulation of hydrophilic counter ions around SMP colloids and the formed hydration force. The repulsion and hydration effect led to the dispersing and deeper draining structure, accompanied by a decreased hydrodynamic radius and increased diffusion coefficient. This hydration force was related to so-called ion specific effect, and electrolyte sodium chloride had a more substantial effect on hydration force than KCl, CsCl, NaBr and NaI. Our results provide an experimental approach to explore the SMP structures, inter-colloid interactions and confirm the non-DLVO forces. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Experimental investigation of methane release from hydrate formation in sandstone through both hydrate dissociation and CO{sub 2} sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Husebo, J.; Graue, A.; Kvamme, B. [Bergen Univ., Bergen (Norway). Dept. of Physics and Technology; Stevens, J.; Howard, J.J. [ConocoPhillips, Ponca City, OK (United States); Baldwin, B.A. [Green Country Petrophysics LLC, Dewey, OK (United States)

    2008-07-01

    Large amounts of natural gas trapped in hydrate reservoirs are found in Arctic regions and in deep offshore locations around the world. Natural gas production from hydrate deposits offer significant potential for future energy needs. However, research is needed in order to propose potential production schemes for natural gas hydrates. Natural gas molecules can be freed from hydrate structured cages by depressurization, by heating and by exposing the hydrate to a substance that will form a thermodynamically more stable hydrate structure. This paper provided a comparison of two approaches for releasing methane from methane hydrate in porous sandstone. The study scope covered the dissociation rate of methane hydrate in porous media through depressurization, and also referred to previous work done on producing methane from hydrates in sandstone while sequestering carbon dioxide (CO{sub 2}). The study was conducted in a laboratory setting. The paper discussed the experimental design which included the placing of a pressure- and temperature-controlled sample holder inside the bore of a magnetic resonance imager. The experimental procedures were then outlined, with reference to hydrate formation; carbon dioxide sequestration; hydrate dissociation experiments with constant volume; and hydrate dissociation experiments at constant pressure. The constant volume experiments demonstrated that in order to dissociate a large amount of hydrate, the initial depressurization had to be significantly lower than the hydrate stability pressure. 9 refs., 9 figs.

  8. Gay and Lesbian Parents

    Science.gov (United States)

    ... Life Listen Español Text Size Email Print Share Gay and Lesbian Parents Page Content Article Body I am gay. Should I worry how this will affect my children? Millions of children have one or more gay and/or lesbian parents. For some children, having ...

  9. Preparation and efficacy assessment of malva nut polysaccharide for skin hydrating products.

    Science.gov (United States)

    Kanlayavattanakul, M; Fungpaisalpong, K; Pumcharoen, M; Lourith, N

    2017-11-01

    Scaphium scaphigerum or malva nut has long been served in Chinese medicine. However, the use of this herb in modern health care applications has, to date, been rarely reported. Maceration of the herb in water afforded malva nut polysaccharide which was standardized. Safety and skin hydrating efficacy of the polysaccharide and products were evaluated in human volunteers. Malva nut polysaccharide (41.71±0.64%) having 36.58±0.51% total sugar content was isolated, with further analysis quantifying ash, carbohydrate, reducing sugar and moisture contents to be 6.05±0.00, 40.06±1.00, 12.20±0.05 and 12.64±0.31%, respectively. The polysaccharide exhibited swelling and hydrating capacities of 0.46±0.01% and 54.46±0.02g/g, with L*, a* and b* of 52.56±0.04, 9.02±0.06 and 18.42±0.03, respectively, and a viscosity of 1263.00±2.00 cps. Accelerated testing indicated the biopolysaccharide to be stable, resulting in no skin irritation in 15 human volunteers. The skin hydrating efficacy as assessed via a randomized single-blind, placebo-controlled study in 24 volunteers highlighted the superior performance of malva nut over the vehicle (moisture retainment for 70min as examined by Corneometer ® CM 825). A stable skin moisturizing gel containing malva nut was developed and was shown to exhibit improved performance over benchmark tamarind and algae polysaccharide gels (after 180min observation). Malva nut polysaccharide has potential as a key ingredient in skin hydrating products, which should encourage its further development. Copyright © 2017 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

  10. Overview of the science activities for the 2002 Mallik gas hydrate production research well program, Mackenzie Delta, N.W.T., Canada

    Science.gov (United States)

    Dallimore, S. R.; Collett, T. S.; Uchida, T.; Weber, M.

    2003-04-01

    With the completion of scientific studies undertaken as part of the 1998 Mallik 2L-38 gas hydrate research well, an international research site was established for the study of Arctic natural gas hydrates in the Mackenzie Delta of northwestern Canada. Quantitative well log analysis and core studies reveal multiple gas hydrate layers from 890 m to 1106 m depth, exceeding 110 m in total thickness. High gas hydrate saturation values, which in some cases exceed 80% of the pore volume, establish the Mallik gas hydrate field as one of the most concentrated gas hydrate reservoirs in the world. Beginning in December 2001 and continuing to the middle of March 2002, two 1188 m deep science observation wells were drilled and instrumented and a 1166 m deep production research well program was carried out. The program participants include 8 partners; The Geological Survey of Canada (GSC), The Japan National Oil Corporation (JNOC), GeoForschungsZentrum Potsdam (GFZ), United States Geological Survey (USGS), United States Department of the Energy (USDOE), India Ministry of Petroleum and Natural Gas (MOPNG)/Gas Authority of India (GAIL) and the Chevron-BP-Burlington joint venture group. In addition the project has been accepted as part of the International Scientific Continental Drilling Program. The Geological Survey of Canada is coordinating the science program for the project and JAPEX Canada Ltd. acted as the designated operator for the fieldwork. Primary objectives of the research program are to advance fundamental geological, geophysical and geochemical studies of the Mallik gas hydrate field and to undertake advanced production testing of a concentrated gas hydrate reservoir. Full-scale field experiments in the production well monitored the physical behavior of the hydrate deposits in response to depressurization and thermal stimulation. The observation wells facilitated cross-hole tomography and vertical seismic profile experiments (before and after production) as well as

  11. Separation of water through gas hydrate formation

    DEFF Research Database (Denmark)

    Boch Andersen, Torben; Thomsen, Kaj

    2009-01-01

    Gas hydrate is normally recognized as a troublemaker in the oil and gas industry. However, gas hydrate has some interesting possibilities when used in connection with separation of water. Nordic Sugar has investigated the possibility of using gas hydrates for concentration of sugar juice. The goal...... of the project was to formulate an alternative separation concept, which can replace the traditional water evaporation process in the sugar production. Work with the separation concept showed that gas hydrates can be used for water separation. The process is not suitable for sugar production because of large...... volumes and the needs for high pressure. The process could be interesting for concentration of heat sensitive, high value products...

  12. Drilling and Production Testing the Methane Hydrate Resource Potential Associated with the Barrow Gas Fields

    Energy Technology Data Exchange (ETDEWEB)

    Steve McRae; Thomas Walsh; Michael Dunn; Michael Cook

    2010-02-22

    In November of 2008, the Department of Energy (DOE) and the North Slope Borough (NSB) committed funding to develop a drilling plan to test the presence of hydrates in the producing formation of at least one of the Barrow Gas Fields, and to develop a production surveillance plan to monitor the behavior of hydrates as dissociation occurs. This drilling and surveillance plan was supported by earlier studies in Phase 1 of the project, including hydrate stability zone modeling, material balance modeling, and full-field history-matched reservoir simulation, all of which support the presence of methane hydrate in association with the Barrow Gas Fields. This Phase 2 of the project, conducted over the past twelve months focused on selecting an optimal location for a hydrate test well; design of a logistics, drilling, completion and testing plan; and estimating costs for the activities. As originally proposed, the project was anticipated to benefit from industry activity in northwest Alaska, with opportunities to share equipment, personnel, services and mobilization and demobilization costs with one of the then-active exploration operators. The activity level dropped off, and this benefit evaporated, although plans for drilling of development wells in the BGF's matured, offering significant synergies and cost savings over a remote stand-alone drilling project. An optimal well location was chosen at the East Barrow No.18 well pad, and a vertical pilot/monitoring well and horizontal production test/surveillance well were engineered for drilling from this location. Both wells were designed with Distributed Temperature Survey (DTS) apparatus for monitoring of the hydrate-free gas interface. Once project scope was developed, a procurement process was implemented to engage the necessary service and equipment providers, and finalize project cost estimates. Based on cost proposals from vendors, total project estimated cost is $17.88 million dollars, inclusive of design work

  13. Micro-structural characterization of the hydration products of bauxite-calcination-method red mud-coal gangue based cementitious materials.

    Science.gov (United States)

    Liu, Xiaoming; Zhang, Na; Yao, Yuan; Sun, Henghu; Feng, Huan

    2013-11-15

    In this research, the micro-structural characterization of the hydration products of red mud-coal gangue based cementitious materials has been investigated through SEM-EDS, (27)Al MAS NMR and (29)Si MAS NMR techniques, in which the used red mud was derived from the bauxite calcination method. The results show that the red mud-coal gangue based cementitious materials mainly form fibrous C-A-S-H gel, needle-shaped/rod-like AFt in the early hydration period. With increasing of the hydration period, densification of the pastes were promoted resulting in the development of strength. EDS analysis shows that with the Ca/Si of red mud-coal gangue based cementitious materials increases, the average Ca/Si and Ca/(Si+Al) atomic ratio of C-A-S-H gel increases, while the average Al/Si atomic ratio of C-A-S-H gel decreases. MAS NMR analysis reveals that Al in the hydration products of red mud-coal gangue based cementitious materials exists in the forms of Al(IV) and Al(VI), but mainly in the form of Al(VI). Increasing the Ca/Si ratio of raw material promotes the conversion of [AlO4] to [AlO6] and inhibits the combination between [AlO4] and [SiO4] to form C-A-S-H gel. Meanwhile, the polymerization degree of [SiO4] in the hydration products declines. Published by Elsevier B.V.

  14. Global identification predicts gay-male identity integration and well-being among Turkish gay men.

    Science.gov (United States)

    Koc, Yasin; Vignoles, Vivian L

    2016-12-01

    In most parts of the world, hegemonic masculinity requires men to endorse traditional masculine ideals, one of which is rejection of homosexuality. Wherever hegemonic masculinity favours heterosexuality over homosexuality, gay males may feel under pressure to negotiate their conflicting male gender and gay sexual identities to maintain positive self-perceptions. However, globalization, as a source of intercultural interaction, might provide a beneficial context for people wishing to create alternative masculinities in the face of hegemonic masculinity. Hence, we tested if global identification would predict higher levels of gay-male identity integration, and indirectly subjective well-being, via alternative masculinity representations for gay and male identities. A community sample of 219 gay and bisexual men from Turkey completed the study. Structural equation modelling revealed that global identification positively predicted gay-male identity integration, and indirectly subjective well-being; however, alternative masculinity representations did not mediate this relationship. Our findings illustrate how identity categories in different domains can intersect and affect each other in complex ways. Moreover, we discuss mental health and well-being implications for gay men living in cultures where they experience high levels of prejudice and stigma. © 2016 The British Psychological Society.

  15. Gas Hydrates | Alaska Division of Geological & Geophysical Surveys

    Science.gov (United States)

    Preliminary Report - Cascadia Margin Gas Hydrates, Volume 204 Initial Report Mallik 2002 GSC Bulletin 585 : Scientific results from the Mallik 2002 gas hydrate production well program Offshore gas hydrate sample

  16. Productivity in Lesbian, Gay, Bisexual, and Transgender Scholarship in Counseling Psychology: Institutional and Individual Ratings for 1990 through 2008

    Science.gov (United States)

    Smith, Nathan Grant

    2010-01-01

    This study examined individual and institutional productivity in lesbian, gay, bisexual, and transgender (LGBT) scholarship published in counseling psychology--oriented journals for the years 1990 through 2008. Eight journals were included in the analyses. An author-weighted score was calculated for each scholar, using a formula developed by…

  17. Fluid Flow Patterns During Production from Gas Hydrates in the Laboratory compared to Field Settings: LARS vs. Mallik

    Science.gov (United States)

    Strauch, B.; Heeschen, K. U.; Priegnitz, M.; Abendroth, S.; Spangenberg, E.; Thaler, J.; Schicks, J. M.

    2015-12-01

    The GFZ's LArge Reservoir Simulator LARS allows for the simulation of the 2008 Mallik gas hydrate production test and the comparison of fluid flow patterns and their driving forces. Do we see the gas flow pattern described for Mallik [Uddin, M. et al., J. Can. Petrol Tech, 50, 70-89, 2011] in a pilot scale test? If so, what are the driving forces? LARS has a network of temperature sensors and an electric resistivity tomography (ERT) enabling a good spatial resolution of gas hydrate occurrences, water and gas distribution, and changes in temperature in the sample. A gas flow meter and a water trap record fluid flow patterns and a backpressure valve has controlled the depressurization equivalent to the three pressure stages (7.0 - 5.0 - 4.2 MPa) applied in the Mallik field test. The environmental temperature (284 K) and confining pressure (13 MPa) have been constant. The depressurization induced immediate endothermic gas hydrate dissociation until re-establishment of the stability conditions by a consequent temperature decrease. Slight gas hydrate dissociation continued at the top and upper lateral border due to the constant heat input from the environment. Here transport pathways were short and permeability higher due to lower gas hydrate saturation. At pressures of 7.0 and 5.0 MPa the LARS tests showed high water flow rates and short irregular spikes of gas production. The gas flow patterns at 4.2 MPa and 3.0MPa resembled those of the Mallik test. In LARS the initial gas surges overlap with times of hydrate instability while water content and lengths of pathways had increased. Water production was at a minimum. A rapidly formed continuous gas phase caused the initial gas surges and only after gas hydrate dissociation decreased to a minimum the single gas bubbles get trapped before slowly coalescing again. In LARS, where pathways were short and no additional water was added, a transport of microbubbles is unlikely to cause a gas surge as suggested for Mallik.

  18. Natural Gas Hydrate as a Storage Mechanism for Safe, Sustainable and Economical Production from Offshore Petroleum Reserves

    Directory of Open Access Journals (Sweden)

    Michael T. Kezirian

    2017-06-01

    Full Text Available Century Fathom presents an innovative process to utilize clathrate hydrates for the production, storage and transportation of natural gas from off-shore energy reserves in deep ocean environments. The production scheme was developed by considering the preferred state of natural gas in the deep ocean and addressing the hazards associated with conventional techniques to transport natural gas. It also is designed to mitigate the significant shipping cost inherent with all methods. The resulting proposed scheme restrains transport in the hydrate form to the ocean and does not attempt to supply energy to the residential consumer. Instead; the target recipients are industrial operations. The resulting operational concept is intrinsically safer by design; environmentally sustainable and significantly cost-effective compared with currently proposed schemes for the use of natural gas hydrates and has the potential to be the optimal solution for new production of reserves; depending on the distance to shore and capacity of the petroleum reserve. A potential additional benefit is the byproduct of desalinated water.

  19. Diverse artikelen in Gay Amsterdam News

    NARCIS (Netherlands)

    Hekma, G.

    2002-01-01

    Vernedering, in: Gay Amsterdam News 125 (jan 2002), pp. 20-21; Webseks, zaad, zweetseks, in: Gay Amsterdam News 126 (feb 2002), pp. 30-31; Wurgseks, in: Gay Amsterdam News 127 (mrt 2002), pp. 30-31; Wijnandus Johannes Sengers (1927-2002), in: Gay Amsterdam News 133 (sept 2002), pp. 49.

  20. Strength Estimation for Hydrate-Bearing Sediments From Direct Shear Tests of Hydrate-Bearing Sand and Silt

    Science.gov (United States)

    Liu, Zhichao; Dai, Sheng; Ning, Fulong; Peng, Li; Wei, Houzhen; Wei, Changfu

    2018-01-01

    Safe and economic methane gas production, as well as the replacement of methane while sequestering carbon in natural hydrate deposits, requires enhanced geomechanical understanding of the strength and volume responses of hydrate-bearing sediments during shear. This study employs a custom-made apparatus to investigate the mechanical and volumetric behaviors of carbon dioxide hydrate-bearing sediments subjected to direct shear. The results show that both peak and residual strengths increase with increased hydrate saturation and vertical stress. Hydrate contributes mainly the cohesion and dilatancy constraint to the peak strength of hydrate-bearing sediments. The postpeak strength reduction is more evident and brittle in specimens with higher hydrate saturation and under lower stress. Significant strength reduction after shear failure is expected in silty sediments with high hydrate saturation Sh ≥ 0.65. Hydrate contribution to the residual strength is mainly by increasing cohesion at low hydrate saturation and friction at high hydrate saturation. Stress state and hydrate saturation are dominating both the stiffness and the strength of hydrate-bearing sediments; thus, a wave velocity-based peak strength prediction model is proposed and validated, which allows for precise estimation of the shear strength of hydrate-bearing sediments through acoustic logging data. This method is advantageous to geomechanical simulators, particularly when the experimental strength data of natural samples are not available.

  1. Novel understanding of calcium silicate hydrate from dilute hydration

    KAUST Repository

    Zhang, Lina

    2017-05-13

    The perspective of calcium silicate hydrate (C-S-H) is still confronting various debates due to its intrinsic complicated structure and properties after decades of studies. In this study, hydration at dilute suspension of w/s equaling to 10 was conducted for tricalcium silicate (C3S) to interpret long-term hydration process and investigate the formation, structure and properties of C-S-H. Based on results from XRD, IR, SEM, NMR and so forth, loose and dense clusters of C-S-H with analogous C/S ratio were obtained along with the corresponding chemical formulae proposed as Ca5Si4O13∙6.2H2O. Crystalline structure inside C-S-H was observed by TEM, which was allocated at the foil-like proportion as well as the edge of wrinkles of the product. The long-term hydration process of C3S in dilute suspension could be sketchily described as migration of calcium hydroxide and in-situ growth of C-S-H with equilibrium silicon in aqueous solution relatively constant and calcium varied.

  2. Older Single Gay Men's Body Talk: Resisting and Rigidifying the Aging Discourse in the Gay Community.

    Science.gov (United States)

    Suen, Yiu Tung

    2017-01-01

    Previous research saw older gay men as subject to structural marginalization of ageism but yet possessing agency to interpret aging in diverse ways. I move beyond this duality, drawing on the theory of defensive othering to understand how older gay men live with the aging discourse in the gay community. Informed by grounded theory, I analyzed interviews with 25 self-identified single gay men aged 50 or above in England inductively. It emerged that many older gay men found it difficult to escape the discourse that marginalizes the aging body. Even when they argued they were the exception and "looked good," they were discursively producing a two-tier system: they themselves as the "good older gay men," as opposed to the other "bad older gay men," who "had given up." Such a defensive othering tactic seemingly allowed them to resist age norms from applying to them personally, but unintentionally reinforced an ageist discourse.

  3. Gay bashing - a rite of passage?

    NARCIS (Netherlands)

    van der Meer, T.A.M.

    2003-01-01

    Most of what is known about the perpetrators of anti-gay violence is reported by victims of such violence. None the less, it is obvious from such reports that 'gay bashers' are overwhelmingly young men who operate in groups, sometimes at gay cruising sites or near gay bars. Drawing on finding from

  4. Clinker mineral hydration at reduced relative humidities

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Hansen, Per Freiesleben; Lachowski, Eric E.

    1999-01-01

    and experimental data are presented showing that C(3)A can hydrate at lower humidities than either C3S or C2S. It is suggested that the initiation of hydration during exposure to water vapour is nucleation controlled. When C(3)A hydrates at low humidity, the characteristic hydration product is C(3)AH(6......Vapour phase hydration of purl cement clinker minerals at reduced relative humidities is described. This is relevant to modern high performance concrete that may self-desiccate during hydration and is also relevant to the quality of the cement during storage. Both the oretical considerations...

  5. Gay and Lesbian Scene in Metelkova

    Directory of Open Access Journals (Sweden)

    Nataša Velikonja

    2013-09-01

    Full Text Available The article deals with the development of the gay and lesbian scene in ACC Metelkova, while specifying the preliminary aspects of establishing and building gay and lesbian activism associated with spatial issues. The struggle for space or occupying public space is vital for the gay and lesbian scene, as it provides not only the necessary socializing opportunities for gays and lesbians, but also does away with the historical hiding of homosexuality in the closet, in seclusion and silence. Because of their autonomy and long-term, continuous existence, homo-clubs at Metelkova contributed to the consolidation of the gay and lesbian scene in Slovenia and significantly improved the opportunities for cultural, social and political expression of gays and lesbians. Such a synthesis of the cultural, social and political, further intensified in Metelkova, and characterizes the gay and lesbian community in Slovenia from the very outset of gay and lesbian activism in 1984. It is this long-term synthesis that keeps this community in Slovenia so vital and politically resilient.

  6. Time lapse survey plan on the first offshore methane hydrate production test in 2013 around the eastern Nankai Trough area by multi-component OBC seismic tool

    Science.gov (United States)

    Inamori, T.; Hayashi, T.; Asakawa, E.; Takahashi, H.; Saeki, T.

    2011-12-01

    We are planning to conduct the multi-component ocean bottom cable (hereafter OBC) seismic survey to monitor the methane hydrate dissociation zone at the 1st offshore methane hydrate production test site in the eastern Nankai Trough, Japan, in 2013. We conducted the first OBC survey in the methane hydrate concentrated zone around the eastern Nankai Trough area in 2006 by RSCS which we developed. We obtained to the good image of methane hydrate bearing layer by P-P section as similar as the conventional surface seismic survey. However, we could not obtain the good image from P-S section compared with P-P section. On the other hand, we studied the sonic velocity distribution at the Mallik 2nd production test before and after in 2007, by the sonic tool data. We could clearly delineate the decrease of S-wave velocity, however, we could not detect the decrease of P-wave velocity because of the presence of the dissociated methane gas from methane hydrate. From these reason we guess the S-wave data is more proper to delineate the condition of the methane hydrate zone at the methane hydrate production tests than P-wave data. We are now developing the new OBC system, which we call Deep-sea Seismic System (hereafter DSS). The sensor of the DSS will install three accelerometers and one hydrophone. A feasibility study to detect the methane hydrate dissociation with the DSS was carried out and we found that the methane hydrate dissociation could be detected with the DSS depending on the zone of the dissociation. And the baseline survey will be held at the 1st offshore methane hydrate production test site in summer 2012. Two monitoring surveys are planned after the methane hydrate production test in 2013. We believe that we will get the good images to delineate the methane hydrate dissociated zone from this time lapse survey. The Authors would like to thank METI, MH21 consortium and JOGMEC for permissions to publish this paper.

  7. KIGAM Seafloor Observation System (KISOS) for the baseline study in monitoring of gas hydrate test production in the Ulleung Basin, Korea

    Science.gov (United States)

    Lee, Sung-rock; Chun, Jong-hwa

    2013-04-01

    For the baseline study in the monitoring gas hydrate test production in the Ulleung Basin, Korea Institute of Geoscience and Mineral Resources (KIGAM) has developed the KIGAM Seafloor Observation System (KISOS) for seafloor exploration using unmanned remotely operated vehicle connected with a ship by a cable. The KISOS consists of a transponder of an acoustic positioning system (USBL), a bottom finding pinger, still camera, video camera, water sampler, and measuring devices (methane, oxygen, CTD, and turbidity sensors) mounted on the unmanned ROV, and a sediment collecting device collecting sediment on the seafloor. It is very important to monitoring the environmental risks (gas leakage and production water/drilling mud discharge) which may be occurred during the gas hydrate test production drilling. The KISOS will be applied to solely conduct baseline study with the KIGAM seafloor monitoring system (KIMOS) of the Korean gas hydrate program in the future. The large scale of environmental monitoring program includes the environmental impact assessment such as seafloor disturbance and subsidence, detection of methane gas leakage around well and cold seep, methane bubbles and dissolved methane, change of marine environments, chemical factor variation of water column and seabed, diffusion of drilling mud and production water, and biological factors of biodiversity and marine habitats before and after drilling test well and nearby areas. The design of the baseline survey will be determined based on the result of SIMAP simulation in 2013. The baseline survey will be performed to provide the gas leakage and production water/drilling mud discharge before and after gas hydrate test production. The field data of the baseline study will be evaluated by the simulation and verification of SIMAP simulator in 2014. In the presentation, the authors would like introduce the configuration of KISOS and applicability to the seafloor observation for the gas hydrate test production in

  8. Are gay communities dying or just in transition? Results from an international consultation examining possible structural change in gay communities.

    Science.gov (United States)

    Simon Rosser, B R; West, William; Weinmeyer, Richard

    2008-05-01

    This study sought to identify how urban gay communities are undergoing structural change, reasons for that change, and implications for HIV prevention planning. Key informants (N=29) at the AIDS Impact Conference from 17 cities in 14 countries completed surveys and participated in a facilitated structured dialog about if gay communities are changing, and if so, how they are changing. In all cities, the virtual gay community was identified as currently larger than the offline physical community. Most cities identified that while the gay population in their cities appeared stable or growing, the gay community appeared in decline. Measures included greater integration of heterosexuals into historically gay-identified neighborhoods and movement of gay persons into suburbs, decreased number of gay bars/clubs, less attendance at gay events, less volunteerism in gay or HIV/AIDS organizations, and the overall declining visibility of gay communities. Participants attributed structural change to multiple factors including gay neighborhood gentrification, achievement of civil rights, less discrimination, a vibrant virtual community, and changes in drug use. Consistent with social assimilation, gay infrastructure, visibility, and community identification appears to be decreasing across cities. HIV prevention planning, interventions, treatment services, and policies need to be re-conceptualized for MSM in the future. Four recommendations for future HIV prevention and research are detailed.

  9. The hydration of slag, part 1: reaction models for blended cement

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, Jos

    2007-01-01

    Reaction models are proposed to quantify the hydration products and to determine the composition of C–S–H from alkali-activated slags (AAS). Products of the slag hydration are first summarized from observations in literature. The main hydration products include C–S–H, hydrotalcite, hydrogarnet, AFm

  10. Lesbian, Gay, Bisexual, and Transgender Health

    Science.gov (United States)

    ... Objectives » Lesbian, Gay, Bisexual, and Transgender Health Lesbian, Gay, Bisexual, and Transgender Health Overview (active tab) Objectives National Snapshots Lesbian, Gay, Bisexual, and Transgender Health View HP2020 Data for: ...

  11. Deconstructing Concealed Gayness Text in The Film Negeri van Oranje: Critical Discourse Analysis

    Directory of Open Access Journals (Sweden)

    Heri Setiawan

    2018-02-01

    Full Text Available As one of the most popular creative cultural products, film sometimes speaks beyond what it presents. It is not always produced merely for entertainment purposes, but also to spread a certain ideology and represent a particular culture. Anchored in queer theory, this research looks at the Indonesian film, Negeri Van Oranje, which was chosen purposely to be analyzed using Fairclough’s critical discourse analysis model with an aim to deconstruct the concealed gayness text in the film. From the analysis, it was found that the gay scenes in the film try to tell its audience about the positions, feelings, challenges, and rejections that Indonesian gay people experience living amongst heteronormative surroundings. Some new notions about gay people’s life in Indonesia are extracted based on the analysis of the gay scenes in the film. The strategy of inserting gay content into a film nationally released in Indonesia is also revealed. The results of the analysis could be used to create a picture of what gay life looks like in Indonesia, a multicultural country that is well-known as the place in which the world’s largest Muslim population dwells.

  12. Well log characterization of natural gas-hydrates

    Science.gov (United States)

    Collett, Timothy S.; Lee, Myung W.

    2012-01-01

    controlling the formation and occurrence of gas hydrate in nature along with data on gas-hydrate reservoir properties (i.e., porosities and permeabilities) needed to accurately predict gas production rates for various gas-hydrate production schemes.

  13. Le problème des hydrates dans le contexte de la production et du transport polyphasiques des pétroles bruts et des gaz naturels. Première partie : physico-chimie de la formation et de la dissociation des hydrates Hydrates Problem Within the Framework of Multiphase Production and Transport of Crude Oils and Natural Gases. Part One: Physical-Chemistry of Hydrates Formation and Dissociation

    Directory of Open Access Journals (Sweden)

    Behar E.

    2006-11-01

    Full Text Available L'exploitation en mer des gisements de combustibles fossiles fluides a amplifié le besoin d'accroître nos connaissances sur les hydrates qui sont susceptibles de boucher les installations de production, de traitement et de transport. Dans cette publication, la structure moléculaire des hydrates I, II et H est rappelée, ensuite l'analyse physico-chimique de leur formation est succinctement décrite tant sur les plans thermodynamique que cinétique. Enfin, les remèdes possibles aux problèmes rencontrés par les compagnies opératrices sont indiqués, essentiellement les inhibiteurs thermodynamiques classiques tels que les alcools ou les sels qui diminuent la température de formation des hydrates, et les additifs dispersants qui évitent la croissance et/ou l'agglomération des cristaux. Pour terminer, une boucle pilote de circulation originale est présentée, ses caractéristiques qui permettent la validation des additifs dispersants dans des conditions hydrodynamiques et physico-chimiques représentatives étant soulignées. Offshore exploitation of fossil fluid fuels has emphasized the need of improving our knowledge on hydrates which can plug production, treatment and transport facilities. In this paper, the molecular structure of I, II and H hydrates is recalled, then the physical-chemistry of their formation is briefly reviewed from both the thermodynamic and the kinetic points of view. Finally, the possible remedies to the problems met by operating companies are described, mainly classical thermodynamic inhibitors such as alcohols or salts which decrease the hydrates formation temperature, and dispersant additives which avoid crystals growth and/or agglomeration. At last an original circulation loop at pilot scale is presented, its characteristics which allow the testing of dispersant additives under representative hydrodynamic and physico-chemical conditions being outlined.

  14. Tapping methane hydrates for unconventional natural gas

    Science.gov (United States)

    Ruppel, Carolyn

    2007-01-01

    Methane hydrate is an icelike form of concentrated methane and water found in the sediments of permafrost regions and marine continental margins at depths far shallower than conventional oil and gas. Despite their relative accessibility and widespread occurrence, methane hydrates have never been tapped to meet increasing global energy demands. With rising natural gas prices, production from these unconventional gas deposits is becoming economically viable, particularly in permafrost areas already being exploited for conventional oil and gas. This article provides an overview of gas hydrate occurrence, resource assessment, exploration, production technologies, renewability, and future challenges.

  15. That’s Gay! Gay as a Slur Among College Students

    Directory of Open Access Journals (Sweden)

    Robert Postic

    2014-11-01

    Full Text Available In recent years, the use of the word “gay” as a synonym for dumb or lame or stupid has become prevalent in our culture. Because of this, it is clear that many individuals do not consider the word to be a slur and are not offended by its use. Using an original data set (N = 790 collected from four Midwestern universities in the winter of 2011-2012, this article examines the characteristics of those college students who perceive the word gay to be a slur or who are offended. We find that those individuals who report having more gay friends are more likely to take offense at the use of the word gay as a slur even after controls are instituted. We also find that, contrary to expectations, attendance at religious services appears to have a direct relationship, with more frequent attenders more likely to express offense at the use of gay as a slur. Egalitarianism also emerged as a significant predictor. We offer suggestions as to why some college students perceive the word to be a slur while a majority of college students do not.

  16. Observed gas hydrate morphologies in marine sediment

    Energy Technology Data Exchange (ETDEWEB)

    Holland, M.; Schultheiss, P.; Roberts, J.; Druce, M. [Geotek Ltd., Daventry, Northamptonshire (United Kingdom)

    2008-07-01

    The morphology of gas hydrate in marine sediments determines the basic physical properties of the sediment-hydrate matrix and provides information regarding the formation of gas hydrate deposits, and the nature of the disruption that will occur on dissociation. Small-scale morphology is useful in estimating the concentrations of gas hydrate from geophysical data. It is also important for predicting their response to climate change or commercial production. Many remote techniques for gas hydrate detection and quantification depend on hydrate morphology. In this study, morphology of gas hydrate was examined in HYACINTH pressure cores from recent seagoing expeditions. Visual and infrared observations from non-pressurized cores were also used. The expeditions and pressure core analysis were described in detail. This paper described the difference between two types of gas hydrate morphologies, notably pore-filling and grain-displacing. Last, the paper addressed the impact of hydrate morphology. It was concluded that a detailed morphology of gas hydrate is an essential component for a full understanding of the past, present, and future of any gas hydrate environment. 14 refs., 4 figs.

  17. In-situ gas hydrate hydrate saturation estimated from various well logs at the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope

    Science.gov (United States)

    Lee, M.W.; Collett, T.S.

    2011-01-01

    In 2006, the U.S. Geological Survey (USGS) completed detailed analysis and interpretation of available 2-D and 3-D seismic data and proposed a viable method for identifying sub-permafrost gas hydrate prospects within the gas hydrate stability zone in the Milne Point area of northern Alaska. To validate the predictions of the USGS and to acquire critical reservoir data needed to develop a long-term production testing program, a well was drilled at the Mount Elbert prospect in February, 2007. Numerous well log data and cores were acquired to estimate in-situ gas hydrate saturations and reservoir properties.Gas hydrate saturations were estimated from various well logs such as nuclear magnetic resonance (NMR), P- and S-wave velocity, and electrical resistivity logs along with pore-water salinity. Gas hydrate saturations from the NMR log agree well with those estimated from P- and S-wave velocity data. Because of the low salinity of the connate water and the low formation temperature, the resistivity of connate water is comparable to that of shale. Therefore, the effect of clay should be accounted for to accurately estimate gas hydrate saturations from the resistivity data. Two highly gas hydrate-saturated intervals are identified - an upper ???43 ft zone with an average gas hydrate saturation of 54% and a lower ???53 ft zone with an average gas hydrate saturation of 50%; both zones reach a maximum of about 75% saturation. ?? 2009.

  18. Overview of the 2006-2008 JOGMEC/NRCan/Aurora Mallik Gas Hydrate Production Test Program

    Science.gov (United States)

    Yamamoto, K.; Dallimore, S. R.

    2008-12-01

    During the winters of 2007 and 2008 the Japan Oil, Gas and Metals National Corporation (JOGMEC) and Natural Resources Canada (NRCan), with Aurora Research Institute as the operator, carried out an on-shore gas hydrate production test program at the Mallik site, Mackenzie Delta, Northwest Territories, Canada. The prime objective of the program was to verify the feasibility of depressurization technique by drawing down the formation pressure across a 12m perforated gas hydrate bearing section. This project was the second full scale production test at this site following the 2002 Japex/JNOC/GSC et al Mallik research program in which seven participants organizatinos from five countries undertook a thermal test using hot water circulation Field work in 2007 was devoted to establishing a production test well, installing monitoring devices outside of casing, conducting base line geophysical studies and undertaking a short test to gain practical experience prior to longer term testing planned for 2008 . Hydrate-dissociated gas was produced to surface by depressurization achieved by lowering the fluid level with a dowhole pump. However, the operation was terminated 60 hours after the start of the pumping mainly due to sand production problems. In spite of the short period (12.5 hours of ellapsed pumping time), at least 830m3 of the gas was produced and accumulated in the borehole. Sand screens were installed across the perforated interval at the bottom hole for the 2008 program to overcome operational problems encountered in 2007 and achieve sustainable gas production. Stable bottom hole flowing pressures were successfully achieved during a 6 day test with continuous pump operation. Sustained gas production was achieved with rates between 2000- 4000m3/day and cummulative gas volume in the surface of approximately 13,000m3. Temperature and pressure data measured at the bottom hole and gas and water production rates gave positive evidence for the high efficiency of gas

  19. Halogen systematics in the Mallik 5L-38 gas hydrate production research well, Northwest Territories, Canada: Implications for the origin of gas hydrates under terrestrial permafrost conditions

    International Nuclear Information System (INIS)

    Tomaru, Hitoshi; Fehn, Udo; Lu, Zunli; Matsumoto, Ryo

    2007-01-01

    The authors report here halogen concentrations in pore waters and sediments collected from the Mallik 5L-38 gas hydrate production research well, a permafrost location in the Mackenzie Delta, Northwest Territories, Canada. Iodine and Br are commonly enriched in waters associated with CH 4 , reflecting the close association between these halogens and source organic materials. Pore waters collected from the Mallik well show I enrichment, by one order of magnitude above that of seawater, particularly in sandy layers below the gas hydrate stability zone (GHSZ). Although Cl and Br concentrations increase with depth similar to the I profile, they remain below seawater values. The increase in I concentrations observed below the GHSZ suggests that I-rich fluids responsible for the accumulation of CH 4 in gas hydrates are preferentially transported through the sandy permeable layers below the GHSZ. The Br and I concentrations and I/Br ratios in Mallik are considerably lower than those in marine gas hydrate locations, demonstrating a terrestrial nature for the organic materials responsible for the CH 4 at the Mallik site. Halogen systematics in Mallik suggest that they are the result of mixing between seawater, freshwater and an I-rich source fluid. The comparison between I/Br ratios in pore waters and sediments speaks against the origin of the source fluids within the host formations of gas hydrates, a finding compatible with the results from a limited set of 129 I/I ratios determined in pore waters, which gives a minimum age of 29 Ma for the source material, i.e. at the lower end of the age range of the host formations. The likely scenario for the gas hydrate formation in Mallik is the derivation of CH 4 together with I from the terrestrial source materials in formations other than the host layers through sandy permeable layers into the present gas hydrate zones

  20. "Kids not rights, is their craving": sex education, gay rights, and the threat of gay teachers.

    Science.gov (United States)

    Graydon, Michael

    2011-08-01

    In July 1977, the Ontario Humans Rights Commission recommended adding sexual orientation to the Code. This move was generally supported but Toronto newspapers and evangelists sought assurances that school boards could still dismiss homosexual teachers. They demanded children be shielded from gay teachers, who they accused of sexual predation. I historically link this to a reenergized fear of homosexuals which emerged during Toronto sex education debates in the 1970s. Later, influenced by Anita Bryant's Save the Children crusade, Toronto newspapers and evangelists argued gay teachers were the dangerous effect of gay rights. After the 1977 murder of Emanuel Jaques and the publication of Gerald Hannon's "Men Loving Boys, Loving Men" article, anti-gay sentiment in Toronto exploded, temporarily halting the progress of gay rights.

  1. Effects of Geomechanical Mechanism on the Gas Production Behavior: A Simulation Study of Class-3 Type Four-Way-Closure Ridge Hydrate Deposit Offshore Southwestern Taiwan

    Science.gov (United States)

    Wu, Cheng-Yueh; Chiu, Yung-Cheng; Huang, Yi-Jyun; Hsieh, Bieng-Zih

    2017-04-01

    The future energy police of Taiwan will heavily rely on the clean energy, including renewable energy and low-carbon energy, to meet the target of mitigating CO2 emission. In addition to developing the renewable energies like solar and wind resources, Taiwan will increase the natural gas consumption to obtain enough electrical power with low-carbon emission. The vast resources of gas hydrates recognized in southwestern offshore Taiwan makes a great opportunity for Taiwan to have own energy resources in the future. Therefore, Taiwan put significant efforts on the evaluation of gas hydrate reserves recently. Production behavior of natural gas dissociated from gas hydrate deposits is an important issue to the hydrate reserves evaluation. The depressurization method is a useful engineering recovery method for gas production from a class-3 type hydrate deposit. The dissociation efficiency will be affected by the pressure drawdown disturbance. However, when the pore pressure of hydrate deposits is depressurized for gas production, the rock matrix will surfer more stresses and the formation deformation might be occurred. The purpose of this study was to investigate the effects of geomechanical mechanism on the gas production from a class-3 hydrate deposit using depressurization method. The case of a class-3 type hydrate deposit of Four-Way-Closure Ridge was studied. In this study a reservoir simulator, STARS, was used. STARS is a multiphase flow, heat transfer, geo-chemical and geo-mechanical mechanisms coupling simulator which is capable to simulate the dissociation/reformation of gas hydrate and the deformation of hydrate reservoirs and overburdens. The simulating ability of STARTS simulator was validated by duplicating the hydrate comparison projects of National Energy Technology Lab. The study target, Four-Way-Closure (FWC) Ridge hydrate deposit, was discovered by the bottom simulating reflectors (BSRs). The geological parameters were collected from the geological and

  2. Thermal conductivity measurements in unsaturated hydrate-bearing sediments

    Science.gov (United States)

    Dai, Sheng; Cha, Jong-Ho; Rosenbaum, Eilis J.; Zhang, Wu; Seol, Yongkoo

    2015-08-01

    Current database on the thermal properties of hydrate-bearing sediments remains limited and has not been able to capture their consequential changes during gas production where vigorous phase changes occur in this unsaturated system. This study uses the transient plane source (TPS) technique to measure the thermal conductivity of methane hydrate-bearing sediments with various hydrate/water/gas saturations. We propose a simplified method to obtain thermal properties from single-sided TPS signatures. Results reveal that both volume fraction and distribution of the pore constituents govern the thermal conductivity of unsaturated specimens. Thermal conductivity hysteresis is observed due to water redistribution and fabric change caused by hydrate formation and dissociation. Measured thermal conductivity increases evidently when hydrate saturation Sh > 30-40%, shifting upward from the geometric mean model prediction to a Pythagorean mixing model. These observations envisage a significant drop in sediment thermal conductivity when residual hydrate/water saturation falls below ~40%, hindering further gas production.

  3. Evaluation of the Gas Production Potential of Marine HydrateDeposits in the Ulleung Basin of the Korean East Sea

    Energy Technology Data Exchange (ETDEWEB)

    Moridis, George J.; Reagan, Matthew T.; Kim, Se-Joon; Seol,Yongkoo; Zhang, Keni

    2007-11-16

    Although significant hydrate deposits are known to exist in the Ulleung Basin of the Korean East Sea, their survey and evaluation as a possible energy resource has not yet been completed. However, it is possible to develop preliminary estimates of their production potential based on the limited data that are currently available. These include the elevation and thickness of the Hydrate-Bearing Layer (HBL), the water depth, and the water temperature at the sea floor. Based on this information, we developed estimates of the local geothermal gradient that bracket its true value. Reasonable estimates of the initial pressure distribution in the HBL can be obtained because it follows closely the hydrostatic. Other critical information needs include the hydrate saturation, and the intrinsic permeabilities of the system formations. These are treated as variables, and sensitivity analysis provides an estimate of their effect on production. Based on the geology of similar deposits, it is unlikely that Ulleung Basin accumulations belong to Class 1 (involving a HBL underlain by a mobile gas zone). If Class 4 (disperse, low saturation accumulations) deposits are involved, they are not likely to have production potential. The most likely scenarios include Class 2 (HBL underlain by a zone of mobile water) or Class 3 (involving only an HBL) accumulations. Assuming nearly impermeable confining boundaries, this numerical study indicates that large production rates (several MMSCFD) are attainable from both Class 2 and Class 3 deposits using conventional technology. The sensitivity analysis demonstrates the dependence of production on the well design, the production rate, the intrinsic permeability of the HBL, the initial pressure, temperature and hydrate saturation, as well as on the thickness of the water zone (Class 2). The study also demonstrates that the presence of confining boundaries is indispensable for the commercially viable production of gas from these deposits.

  4. The hydration of slag, part 1: reaction models for alkali-activated slag

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, H.J.H.

    2007-01-01

    Reaction models are proposed to quantify the hydration products and to determine the composition of C–S–H from alkali-activated slags (AAS). Products of the slag hydration are first summarized from observations in literature. The main hydration products include C–S–H, hydrotalcite, hydrogarnet, AFm

  5. Supramolecular Organization of Nonstoichiometric Drug Hydrates: Dapsone

    Science.gov (United States)

    Braun, Doris E.; Griesser, Ulrich J.

    2018-01-01

    The observed moisture- and temperature dependent transformations of the dapsone (4,4′-diaminodiphenyl sulfone, DDS) 0. 33-hydrate were correlated to its structure and the number and strength of the water-DDS intermolecular interactions. A combination of characterization techniques was used, including thermal analysis (hot-stage microscopy, differential scanning calorimetry and thermogravimetric analysis), gravimetric moisture sorption/desorption studies and variable humidity powder X-ray diffraction, along with computational modeling (crystal structure prediction and pair-wise intermolecular energy calculations). Depending on the relative humidity the hydrate contains between 0 and 0.33 molecules of water per molecule DDS. The crystal structure is retained upon dehydration indicating that DDS hydrate shows a non-stoichiometric (de)hydration behavior. Unexpectedly, the water molecules are not located in structural channels but at isolated-sites of the host framework, which is counterintuitively for a hydrate with non-stoichiometric behavior. The water-DDS interactions were estimated to be weaker than water-host interactions that are commonly observed in stoichiometric hydrates and the lattice energies of the isomorphic dehydration product (hydrate structure without water molecules) and (form III) differ only by ~1 kJ mol−1. The computational generation of hypothetical monohydrates confirms that the hydrate with the unusual DDS:water ratio of 3:1 is more stable than a feasible monohydrate structure. Overall, this study highlights that a deeper understanding of the formation of hydrates with non-stoichiometric behavior requires a multidisciplinary approach including suitable experimental and computational methods providing a firm basis for the development and manufacturing of high quality drug products. PMID:29520359

  6. First-principles elasticity of monocarboaluminate hydrates

    KAUST Repository

    Moon, J.; Yoon, S.; Wentzcovitch, R. M.; Monteiro, P. J. M.

    2014-01-01

    The elasticity of monocarboaluminate hydrates, 3CaO·Al2O3·CaCO3·xH2O (x = 11 or 8), has been investigated by first-principles calculations. Previous experimental study revealed that the fully hydrated monocarboaluminate (x = 11) exhibits exceptionally low compressibility compared to other reported calcium aluminate hydrates. This stiff hydration product can contribute to the strength of concrete made with Portland cements containing calcium carbonates. In this study, full elastic tensors and mechanical properties of the crystal structures with different water contents (x = 11 or 8) are computed by first-principles methods based on density functional theory. The results indicate that the compressibility of monocarboaluminate is highly dependent on the water content in the interlayer region. The structure also becomes more isotropic with the addition of water molecules in this region. Since the monocarboaluminate is a key hydration product of limestone added cement, elasticity of the crystal is important to understand its mechanical impact on concrete. Besides, it is put forth that this theoretical calculation will be useful in predicting the elastic properties of other complex cementitous materials and the influence of ion exchange on compressibility.

  7. First-principles elasticity of monocarboaluminate hydrates

    KAUST Repository

    Moon, J.

    2014-07-01

    The elasticity of monocarboaluminate hydrates, 3CaO·Al2O3·CaCO3·xH2O (x = 11 or 8), has been investigated by first-principles calculations. Previous experimental study revealed that the fully hydrated monocarboaluminate (x = 11) exhibits exceptionally low compressibility compared to other reported calcium aluminate hydrates. This stiff hydration product can contribute to the strength of concrete made with Portland cements containing calcium carbonates. In this study, full elastic tensors and mechanical properties of the crystal structures with different water contents (x = 11 or 8) are computed by first-principles methods based on density functional theory. The results indicate that the compressibility of monocarboaluminate is highly dependent on the water content in the interlayer region. The structure also becomes more isotropic with the addition of water molecules in this region. Since the monocarboaluminate is a key hydration product of limestone added cement, elasticity of the crystal is important to understand its mechanical impact on concrete. Besides, it is put forth that this theoretical calculation will be useful in predicting the elastic properties of other complex cementitous materials and the influence of ion exchange on compressibility.

  8. Toward production from gas hydrates: Current status, assessment of resources, and simulation-based evaluation of technology and potential

    Science.gov (United States)

    Moridis, G.J.; Collett, T.S.; Boswell, R.; Kurihara, M.; Reagan, M.T.; Koh, C.; Sloan, E.D.

    2009-01-01

    Gas hydrates (GHs) are a vast energy resource with global distribution in the permafrost and in the oceans. Even if conservative estimates are considered and only a small fraction is recoverable, the sheer size of the resource is so large that it demands evaluation as a potential energy source. In this review paper, we discuss the distribution of natural GH accumulations, the status of the primary international research and development (R&D) programs, and the remaining science and technological challenges facing the commercialization of production. After a brief examination of GH accumulations that are well characterized and appear to be models for future development and gas production, we analyze the role of numerical simulation in the assessment of the hydrate-production potential, identify the data needs for reliable predictions, evaluate the status of knowledge with regard to these needs, discuss knowledge gaps and their impact, and reach the conclusion that the numerical-simulation capabilities are quite advanced and that the related gaps either are not significant or are being addressed. We review the current body of literature relevant to potential productivity from different types of GH deposits and determine that there are consistent indications of a large production potential at high rates across long periods from a wide variety of hydrate deposits. Finally, we identify (a) features, conditions, geology and techniques that are desirable in potential production targets; (b) methods to maximize production; and (c) some of the conditions and characteristics that render certain GH deposits undesirable for production. Copyright ?? 2009 Society of Petroleum Engineers.

  9. Conflict Management of Gay Couples' Relationship in Semarang

    OpenAIRE

    Putri Aprilina, Noni; Naryoso, Agus

    2017-01-01

    Gay people in Indonesia are still a minority. The low population of gays causes jealousy and possessiveness to be the gay nature feeling of gay with each other. They will be very angry if their partner see theyre dating someone else (Aditya, 2009). Based on the above phenomenon can be concluded that gays also experience conflict in the relationship they live. Conflict experienced by gay is different from one another. Some show conflict-related issues of jealousy, usually higher sexual jealous...

  10. Lesbians, gays and religion.

    Science.gov (United States)

    Newmanxy, Bernie Sue

    2002-10-01

    SUMMARY This study measured the effects of religious affiliation and gender on attitudes about lesbians and gay men among 2,846 college graduates who were beginning graduate study in social work or counseling. Males were more negative than females in their attitudes toward both lesbians and gay men. Conservative Protestants were the most negative in their attitudes toward lesbians and gay men, while those who were Atheist, Agnostic, Jewish or claimed no religion were most positive. Beliefs that the Bible forbids homosexuality are discussed and readings and arguments challenging this belief that can be used as class content are presented.

  11. Physical Properties of Gas Hydrates: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Gabitto, Jorge [Prairie View A& M University; Tsouris, Costas [ORNL

    2010-01-01

    Methane gas hydrates in sediments have been studied by several investigators as a possible future energy resource. Recent hydrate reserves have been estimated at approximately 1016?m3 of methane gas worldwide at standard temperature and pressure conditions. In situ dissociation of natural gas hydrate is necessary in order to commercially exploit the resource from the natural-gas-hydrate-bearing sediment. The presence of gas hydrates in sediments dramatically alters some of the normal physical properties of the sediment. These changes can be detected by field measurements and by down-hole logs. An understanding of the physical properties of hydrate-bearing sediments is necessary for interpretation of geophysical data collected in field settings, borehole, and slope stability analyses; reservoir simulation; and production models. This work reviews information available in literature related to the physical properties of sediments containing gas hydrates. A brief review of the physical properties of bulk gas hydrates is included. Detection methods, morphology, and relevant physical properties of gas-hydrate-bearing sediments are also discussed.

  12. Gas hydrates forming and decomposition conditions analysis

    Directory of Open Access Journals (Sweden)

    А. М. Павленко

    2017-07-01

    Full Text Available The concept of gas hydrates has been defined; their brief description has been given; factors that affect the formation and decomposition of the hydrates have been reported; their distribution, structure and thermodynamic conditions determining the gas hydrates formation disposition in gas pipelines have been considered. Advantages and disadvantages of the known methods for removing gas hydrate plugs in the pipeline have been analyzed, the necessity of their further studies has been proved. In addition to the negative impact on the process of gas extraction, the hydrates properties make it possible to outline the following possible fields of their industrial use: obtaining ultrahigh pressures in confined spaces at the hydrate decomposition; separating hydrocarbon mixtures by successive transfer of individual components through the hydrate given the mode; obtaining cold due to heat absorption at the hydrate decomposition; elimination of the open gas fountain by means of hydrate plugs in the bore hole of the gushing gasser; seawater desalination, based on the hydrate ability to only bind water molecules into the solid state; wastewater purification; gas storage in the hydrate state; dispersion of high temperature fog and clouds by means of hydrates; water-hydrates emulsion injection into the productive strata to raise the oil recovery factor; obtaining cold in the gas processing to cool the gas, etc.

  13. Biodiesel production from palm oil using hydrated lime-derived CaO as a low-cost basic heterogeneous catalyst

    International Nuclear Information System (INIS)

    Roschat, Wuttichai; Siritanon, Theeranun; Yoosuk, Boonyawan; Promarak, Vinich

    2016-01-01

    Graphical abstract: Hydrated lime-derived CaO can be utilized as high efficient heterogeneous solid catalyst for transesterification of palm oil to biodiesel product. - Highlights: • CaO with high surface area and pore volume was successfully prepared from hydrated lime using a simple method. • Hydrated lime-derived CaO were used as a catalyst in transesterification of palm oil to biodiesel. • Over 97% FAME yield was achieved from transesterification of palm oil in 2 h. • This CaO has high potential for applications as green and low-cost catalyst. - Abstract: In this study, hydrated lime-derived calcium oxide (CaO) was used as a catalyst for the transesterification of palm oil. The catalysts were characterized by TG-DTA, XRD, XRF, FT-IR, SEM, Hammett indicator method, TPD-CO_2 and BET by N_2 adsorption. Under the optimal conditions at catalyst loading of 6 wt.%, methanol/oil molar ratio of 15:1, reaction temperature 65 °C, and stirring rate of 200 rpm; 97% yield of biodiesel could be achieved in 2 h. Effects of water amount were investigated and the catalyst could tolerate high water content of 5 wt.%. The kinetic of the reaction followed pseudo-first order with the activation energy (Ea) of 121.12 kJ/mol and frequency factor (A) of 1.203 × 10"1"7 min"−"1. After treatments, high quality biodiesel was obtained which indicated that the very cheap hydrated lime-derived CaO showed excellent catalytic activity and high potential for applications in biodiesel production.

  14. Homosexuality and Pro-Gay Ideology as Pathogens? Implications of a Disease-Spread Lay Model for Understanding Anti-Gay Behaviors.

    Science.gov (United States)

    Filip-Crawford, Gabrielle; Neuberg, Steven L

    2015-09-03

    Negative behaviors targeting gay men and lesbians range from violent physical assault to casting a vote against gay marriage, with very different implications for those targeted. Existing accounts of such actions, however, are unable to differentially predict specific anti-gay behaviors, leaving a large theoretical hole in the literature and hindering the design of effective interventions. We propose (a) that many sexually prejudiced laypersons conceptualize homosexuality and pro-gay ideology as "contaminants" analogous to infectious pathogens and (b) that anti-gay behaviors can thus be viewed as strategic attempts to prevent, contain, treat, or eradicate the "pathogens" of homosexuality and pro-gay ideology. By considering analogues to disease-spread processes (e.g., susceptibility of specific subpopulations, inoculation procedures, prevalence in the local environment, interconnections among community members), we derive novel predictions regarding the incidence and nature of anti-gay behaviors and provide leverage for creating more tailored interventions to reduce such discrimination. © 2015 by the Society for Personality and Social Psychology, Inc.

  15. Flow assurance intervention, hydrates remediation

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, Christopher S. [Oceaneering International Inc., Houston, TX (United States)

    2012-07-01

    This paper addresses the issues of removing hydrates in sub sea flow lines and associated equipment with an Remotely Operated Vehicle (ROV) of opportunity and a multi-service-vessel (MSV). The paper is split into three topics: the equipment used with the ROV, assessing the interface points and handling fluids produced from drawing down the pressure. Each section is explained thoroughly and backed up with real world experience. The equipment section details information from actual jobs performed and why the particular components were utilized. The system is generally contained in an ROV mounted skid. Pumps are utilized to draw down the pressure inside the hydrated section of equipment, removing one of the three necessary components for hydrates formation. Once the section is pumped down, several options exist for handling the fluids pumped out of the system: pumping to surface, re-injection into the well, or injection into an operating flow line. This method of hydrates remediation is both economical and timely. Hydrate blockages form in low temperatures and high pressures. Reducing the pressure or increasing the temperature so the conditions lie to the right of the hydrate dissociation curve will slowly decompose the blockage. Depressurization and the use of MEG or methanol will give favorable conditions to remove the hydrate plug. Oceaneering has the capabilities to remove hydrates using the FRS in conjunction with an installation vessel to dispose of the gas and fluid removed from the flow line. Hydrate remediation techniques should be implemented into the initial design to reduce costs later. The cost of stopped production combined with the day rate for equipment needed for hydrate removal outweighs the costs if no technique is utilized. (author)

  16. Methane hydrates in nature - Current knowledge and challenges

    Science.gov (United States)

    Collett, Timothy S.

    2014-01-01

    Recognizing the importance of methane hydrate research and the need for a coordinated effort, the United States Congress enacted the Methane Hydrate Research and Development Act of 2000. At the same time, the Ministry of International Trade and Industry in Japan launched a research program to develop plans for a methane hydrate exploratory drilling project in the Nankai Trough. India, China, the Republic of Korea, and other nations also have established large methane hydrate research and development programs. Government-funded scientific research drilling expeditions and production test studies have provided a wealth of information on the occurrence of methane hydrates in nature. Numerous studies have shown that the amount of gas stored as methane hydrates in the world may exceed the volume of known organic carbon sources. However, methane hydrates represent both a scientific and technical challenge, and much remains to be learned about their characteristics and occurrence in nature. Methane hydrate research in recent years has mostly focused on: (1) documenting the geologic parameters that control the occurrence and stability of methane hydrates in nature, (2) assessing the volume of natural gas stored within various methane hydrate accumulations, (3) analyzing the production response and characteristics of methane hydrates, (4) identifying and predicting natural and induced environmental and climate impacts of natural methane hydrates, (5) analyzing the methane hydrate role as a geohazard, (6) establishing the means to detect and characterize methane hydrate accumulations using geologic and geophysical data, and (7) establishing the thermodynamic phase equilibrium properties of methane hydrates as a function of temperature, pressure, and gas composition. The U.S. Department of Energy (DOE) and the Consortium for Ocean Leadership (COL) combined their efforts in 2012 to assess the contributions that scientific drilling has made and could continue to make to advance

  17. A gas production system from methane hydrate layers by hot water injection and BHP control with radial horizontal wells

    Energy Technology Data Exchange (ETDEWEB)

    Yamakawa, T.; Ono, S.; Iwamoto, A.; Sugai, Y.; Sasaki, K. [Kyushu Univ., Fukuoka, Fukuoka (Japan)

    2010-07-01

    Reservoir characterization of methane hydrate (MH) bearing turbidite channel in the eastern Nankai Trough, in Japan has been performed to develop a gas production strategy. This paper proposed a gas production system from methane hydrate (MH) sediment layers by combining the hot water injection method and bottom hole pressure control at the production well using radial horizontal wells. Numerical simulations of the cylindrical homogeneous MH layer model were performed in order to evaluate gas production characteristics by the depressurization method with bottom hole pressure control. In addition, the effects of numerical block modeling and averaging physical properties of MH layers were presented. According to numerical simulations, combining the existing production system with hot water injection and bottom hole pressure control results in an outward expansion of the hot water chamber from the center of the MH layer with continuous gas production. 10 refs., 15 figs.

  18. Wedding Imagery and Public Support for Gay Marriage.

    Science.gov (United States)

    Brewer, Paul R; Wilson, David C; Habegger, Michael

    2016-08-01

    This study uses an experiment embedded in a large, nationally representative survey to test whether exposure to imagery of a gay or lesbian couple's wedding influences support for gay marriage. It also tests whether any such effects depend on the nature of the image (gay or lesbian couple, kissing or not) and viewer characteristics (sex, age, race, education, religion, and ideology). Results show that exposure to imagery of a gay couple kissing reduced support for gay marriage relative to the baseline. Other image treatments (gay couple not kissing, lesbian couple kissing, lesbian couple not kissing) did not significantly influence opinion.

  19. Characterization and Prediction of the Gas Hydrate Reservoir at the Second Offshore Gas Production Test Site in the Eastern Nankai Trough, Japan

    Directory of Open Access Journals (Sweden)

    Machiko Tamaki

    2017-10-01

    Full Text Available Following the world’s first offshore production test that was conducted from a gas hydrate reservoir by a depressurization technique in 2013, the second offshore production test has been planned in the eastern Nankai Trough. In 2016, the drilling survey was performed ahead of the production test, and logging data that covers the reservoir interval were newly obtained from three wells around the test site: one well for geological survey, and two wells for monitoring surveys, during the production test. The formation evaluation using the well log data suggested that our target reservoir has a more significant heterogeneity in the gas hydrate saturation distribution than we expected, although lateral continuity of sand layers is relatively good. To evaluate the spatial distribution of gas hydrate, the integration analysis using well and seismic data was performed. The seismic amplitude analysis supports the lateral reservoir heterogeneity that has a significant positive correlation with the resistivity log data at the well locations. The spatial distribution of the apparent low-resistivity interval within the reservoir observed from log data was investigated by the P-velocity volume derived from seismic inversion. The integrated results were utilized for the pre-drill prediction of the reservoir quality at the producing wells. These approaches will reduce the risk of future commercial production from the gas hydrate reservoir.

  20. Supramolecular Organization of Nonstoichiometric Drug Hydrates: Dapsone

    Directory of Open Access Journals (Sweden)

    Doris E. Braun

    2018-02-01

    Full Text Available The observed moisture- and temperature dependent transformations of the dapsone (4,4′-diaminodiphenyl sulfone, DDS 0. 33-hydrate were correlated to its structure and the number and strength of the water-DDS intermolecular interactions. A combination of characterization techniques was used, including thermal analysis (hot-stage microscopy, differential scanning calorimetry and thermogravimetric analysis, gravimetric moisture sorption/desorption studies and variable humidity powder X-ray diffraction, along with computational modeling (crystal structure prediction and pair-wise intermolecular energy calculations. Depending on the relative humidity the hydrate contains between 0 and 0.33 molecules of water per molecule DDS. The crystal structure is retained upon dehydration indicating that DDS hydrate shows a non-stoichiometric (dehydration behavior. Unexpectedly, the water molecules are not located in structural channels but at isolated-sites of the host framework, which is counterintuitively for a hydrate with non-stoichiometric behavior. The water-DDS interactions were estimated to be weaker than water-host interactions that are commonly observed in stoichiometric hydrates and the lattice energies of the isomorphic dehydration product (hydrate structure without water molecules and (form III differ only by ~1 kJ mol−1. The computational generation of hypothetical monohydrates confirms that the hydrate with the unusual DDS:water ratio of 3:1 is more stable than a feasible monohydrate structure. Overall, this study highlights that a deeper understanding of the formation of hydrates with non-stoichiometric behavior requires a multidisciplinary approach including suitable experimental and computational methods providing a firm basis for the development and manufacturing of high quality drug products.

  1. Gay and Lesbian Medical Association

    Science.gov (United States)

    ... men who have sex with men (MSM), including gay and bisexual men. GLMA President Jesse Joad, MD, ... to establish clear and comprehensive regulations ensuring lesbian, gay, bisexual and transgender people do not face discrimination ...

  2. Ultrasonic sound speed of hydrating calcium sulphate hemihydrate; part 2, the correlation of sound velocity to hydration degree

    NARCIS (Netherlands)

    de Korte, A.C.J.; Brouwers, Jos; Fischer, H.B; Matthes, C.; Beuthan, C.

    2011-01-01

    In this article the sound velocity through a mix is correlated to the hydration degree of the mix. Models are presented predicting the sound velocity through fresh slurries and hardened products. These two states correspond to the starting and finishing point of the hydration process. The present

  3. Ultrasonic sound speed of hydrating calcium sulphate hemihydrate; Part 2, The correlation of sound velocity to hydration degree

    NARCIS (Netherlands)

    Korte, de A.C.J.; Brouwers, H.J.H.; Fischer, H.B.; Mattes, Chr.; Beutha, C.

    2011-01-01

    In this article the sound velocity through a mix is correlated to the hydration degree of the mix. Models are presented predicting the sound velocity through fresh slurries and hardened products. These two states correspond to the starting and finishing point of the hydration process. The present

  4. Thermal conductivity of hydrate-bearing sediments

    Science.gov (United States)

    Cortes, Douglas D.; Martin, Ana I.; Yun, Tae Sup; Francisca, Franco M.; Santamarina, J. Carlos; Ruppel, Carolyn D.

    2009-01-01

    A thorough understanding of the thermal conductivity of hydrate-bearing sediments is necessary for evaluating phase transformation processes that would accompany energy production from gas hydrate deposits and for estimating regional heat flow based on the observed depth to the base of the gas hydrate stability zone. The coexistence of multiple phases (gas hydrate, liquid and gas pore fill, and solid sediment grains) and their complex spatial arrangement hinder the a priori prediction of the thermal conductivity of hydrate-bearing sediments. Previous studies have been unable to capture the full parameter space covered by variations in grain size, specific surface, degree of saturation, nature of pore filling material, and effective stress for hydrate-bearing samples. Here we report on systematic measurements of the thermal conductivity of air dry, water- and tetrohydrofuran (THF)-saturated, and THF hydrate–saturated sand and clay samples at vertical effective stress of 0.05 to 1 MPa (corresponding to depths as great as 100 m below seafloor). Results reveal that the bulk thermal conductivity of the samples in every case reflects a complex interplay among particle size, effective stress, porosity, and fluid-versus-hydrate filled pore spaces. The thermal conductivity of THF hydrate–bearing soils increases upon hydrate formation although the thermal conductivities of THF solution and THF hydrate are almost the same. Several mechanisms can contribute to this effect including cryogenic suction during hydrate crystal growth and the ensuing porosity reduction in the surrounding sediment, increased mean effective stress due to hydrate formation under zero lateral strain conditions, and decreased interface thermal impedance as grain-liquid interfaces are transformed into grain-hydrate interfaces.

  5. A high yield process for hydrate formation

    Energy Technology Data Exchange (ETDEWEB)

    Giavarini, C.; Maccioni, F. [Univ. of Roma La Sapienza, Roma (Italy). Dept. of Chemical Engineering

    2008-07-01

    Due to the large quantities of natural gas stored in deep ocean hydrates, hydrate reservoirs are a substantial energy resource. Hydrates concentrate methane by as much as a factor of 164. As such, several natural gas transportation and storage systems using gas hydrates have been studied, and many of them are nearing practical use. In these systems, the hydrate is produced as a slurry by a spray process at approximately 7 megapascal (MPa), and then shaped into pellets. The use of a spray process, instead of a conventional stirred vessel is necessary in order to reach high hydrate concentrations in the hydrate-ice system. This paper presented a new procedure to produce a bulk of concentrated methane hydrate in a static traditional reactor at moderate pressure, controlling pressure and temperature in the interval between ice melting and the hydrate equilibrium curve. This paper discussed the experimental procedure which included formation of methane hydrate at approximately 5 MPa and 2 degrees Celsius in a reaction calorimeter at a volume of two liters. Results were also discussed. It was concluded that the procedure seemed suitable for the development of a gas hydrate storage and transport technology. It was found that the spray procedure took more time, but could be sped up and made continuous by using two vessels, one for hydrate formation and the other for hydrate concentration. The advantage was the production of a concentrated hydrate, using a simpler equipment and working at lower pressures respect to the spray process. 9 refs., 5 figs.

  6. Thermodynamic stability and guest distribution of CH4/N2/CO2 mixed hydrates for methane hydrate production using N2/CO2 injection

    International Nuclear Information System (INIS)

    Lim, Dongwook; Ro, Hyeyoon; Seo, Yongwon; Seo, Young-ju; Lee, Joo Yong; Kim, Se-Joon; Lee, Jaehyoung; Lee, Huen

    2017-01-01

    Highlights: • We examine the thermodynamic stability and guest distribution of CH 4 /N 2 /CO 2 mixed hydrates. • Phase equilibria of the CH 4 /N 2 /CO 2 mixed hydrates were measured to determine the thermodynamic stability. • The N 2 /CO 2 ratio of the hydrate phase is almost constant despite the enrichment of CO 2 in the hydrate phase. • 13 C NMR results indicate the preferential occupation of N 2 and CO 2 in the small and large cages of sI hydrates, respectively. - Abstract: In this study, thermodynamic stability and cage occupation behavior in the CH 4 – CO 2 replacement, which occurs in natural gas hydrate reservoirs by injecting flue gas, were investigated with a primary focus on phase equilibria and composition analysis. The phase equilibria of CH 4 /N 2 /CO 2 mixed hydrates with various compositions were measured to determine the thermodynamic stability of gas hydrate deposits replaced by N 2 /CO 2 gas mixtures. The fractional experimental pressure differences (Δp/p) with respect to the CSMGem predictions were found to range from −0.11 to −0.02. The composition analysis for various feed gas mixtures with a fixed N 2 /CO 2 ratio (4.0) shows that CO 2 is enriched in the hydrate phase, and the N 2 /CO 2 ratio in the hydrate phase is independent of the feed CH 4 fractions. Moreover, 13 C NMR measurements indicate that N 2 molecules preferentially occupy the small 5 12 cages of sI hydrates while the CO 2 molecules preferentially occupy the large 5 12 6 2 cages, resulting in an almost constant area ratio of CH 4 molecules in the large to small cages of the CH 4 /N 2 /CO 2 mixed hydrates. The overall experimental results provide a better understanding of stability conditions and guest distributions in natural gas hydrate deposits during CH 4 – flue gas replacement.

  7. Gay men seeking surrogacy to achieve parenthood.

    Science.gov (United States)

    Norton, Wendy; Hudson, Nicky; Culley, Lorraine

    2013-09-01

    Assisted reproduction technologies have developed at an extraordinary rate in recent years. This, combined with the changing landscape of legal, technical and social possibilities, enables gay men to consider their options for fatherhood as new opportunities emerge for them to create families. Media coverage of gay celebrities embracing surrogacy as a way of having a family and high-profile legal cases have raised awareness of surrogacy across the world. However, gay fatherhood achieved through assisted reproduction is a highly under-researched area, both in the UK and internationally. The research that currently exists on gay fatherhood is largely related to gay men who become parents through processes such as adoption and fostering and children conceived through previous heterosexual relationships. Much of this evidence has centred on parenting experiences, the outcomes for children or the legal perspectives. This paper outlines the different types of surrogacy and the legal issues facing gay men who choose this route to parenthood, summarizes the limited research on gay men and surrogacy and discusses gaps in the current knowledge base. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  8. Reconsideration on Hydration of Sodium Ion: From Micro-Hydration to Bulk Hydration

    Science.gov (United States)

    Yongquan, Zhou; Chunhui, Fang; Yan, Fang; Fayan, Zhu; Haiwen, Ge; Hongyan, Liu

    2017-12-01

    Micro hydration structures of the sodium ion, [Na(H2O) n ]+, n = 1-12, were probed by density functional theory (DFT) at B3LYP/aug-cc-pVDZ level in both gaseous and aqueous phase. The predicted equilibrium sodium-oxygen distance of 0.240 nm at the present level of theory. The four-, five- and six-coordinated cluster can transform from each other at the ambient condition. The analysis of the successive water binding energy and natural charge population (NBO) on Na+ clearly shows that the influence of Na+ on the surrounding water molecules goes beyond the first hydration shell with the hydration number of 6. The Car-Parrinello molecular dynamic simulation shows that only the first hydration sphere can be found, and the hydration number of Na+ is 5.2 and the hydration distance ( r Na-O) is 0.235 nm. All our simulations mentioned in the present paper show an excellent agreement with the diffraction result from X-ray scattering study.

  9. Energy from gas hydrates - assessing the opportunities and challenges for Canada: report of the expert panel on gas hydrates

    International Nuclear Information System (INIS)

    2008-09-01

    significant safety issues, unique to the production of gas from gas hydrate, that were not already encountered and addressed in the course of more conventional natural gas production, both onshore and offshore. refs., tabs., figs

  10. Maximum Recoverable Gas from Hydrate Bearing Sediments by Depressurization

    KAUST Repository

    Terzariol, Marco

    2017-11-13

    The estimation of gas production rates from hydrate bearing sediments requires complex numerical simulations. This manuscript presents a set of simple and robust analytical solutions to estimate the maximum depressurization-driven recoverable gas. These limiting-equilibrium solutions are established when the dissociation front reaches steady state conditions and ceases to expand further. Analytical solutions show the relevance of (1) relative permeabilities between the hydrate free sediment, the hydrate bearing sediment, and the aquitard layers, and (2) the extent of depressurization in terms of the fluid pressures at the well, at the phase boundary, and in the far field. Close form solutions for the size of the produced zone allow for expeditious financial analyses; results highlight the need for innovative production strategies in order to make hydrate accumulations an economically-viable energy resource. Horizontal directional drilling and multi-wellpoint seafloor dewatering installations may lead to advantageous production strategies in shallow seafloor reservoirs.

  11. Hydration study of ordinary portland cement in the presence of zinc ions

    Directory of Open Access Journals (Sweden)

    Monica Adriana Trezza

    2007-12-01

    Full Text Available Hydration products of Portland cement pastes, hydrated in water and in the presence of zinc ions were studied comparatively at different ages. Hydration products were studied by X ray diffractions (XRD and infrared spectroscopy (IR. Although IR is not frequently used in cement chemistry, it evidenced a new phase Ca(Zn(OH32. 2H2O formed during cement hydration in the presence of zinc. The significant retardation of early cement hydration in the presence of zinc is assessed in detail by differential calorimetry as a complement to the study carried out by IR and XRD, providing evidence that permits to evaluate the kinetic of the early hydration.

  12. Experimental Investigation of Effect on Hydrate Formation in Spray Reactor

    Directory of Open Access Journals (Sweden)

    Jianzhong Zhao

    2015-01-01

    Full Text Available The effects of reaction condition on hydrate formation were conducted in spray reactor. The temperature, pressure, and gas volume of reaction on hydrate formation were measured in pure water and SDS solutions at different temperature and pressure with a high-pressure experimental rig for hydrate formation. The experimental data and result reveal that additives could improve the hydrate formation rate and gas storage capacity. Temperature and pressure can restrict the hydrate formation. Lower temperature and higher pressure can promote hydrate formation, but they can increase production cost. So these factors should be considered synthetically. The investigation will promote the advance of gas storage technology in hydrates.

  13. Legislators' positions on gay and lesbian rights: the personal and political.

    Science.gov (United States)

    Herrick, Rebekah

    2010-01-01

    This article examines state legislators' public position on gay and lesbian rights by using responses to survey data on their positions toward civil unions and inclusion of sexual orientation in anti-job discrimination laws. The research finds that although state legislators are mixed on their positions, they are less supportive of gay and lesbian rights than is the general public. It also finds that their public positions are a product of both their personal beliefs and values as well as their political calculations. The implications of these findings are explored.

  14. A Scanning Transmission X-ray Microscopy Study of Cubic and Orthorhombic C3A and Their Hydration Products in the Presence of Gypsum

    Directory of Open Access Journals (Sweden)

    Vanessa Rheinheimer

    2016-08-01

    Full Text Available This paper shows the microstructural differences and phase characterization of pure phases and hydrated products of the cubic and orthorhombic (Na-doped polymorphs of tricalcium aluminate (C3A, which are commonly found in traditional Portland cements. Pure, anhydrous samples were characterized using scanning transmission X-ray microscopy (STXM, X-ray photoelectron spectroscopy (XPS and X-ray diffraction (XRD and demonstrated differences in the chemical and mineralogical composition as well as the morphology on a micro/nano-scale. C3A/gypsum blends with mass ratios of 0.2 and 1.9 were hydrated using a water/C3A ratio of 1.2, and the products obtained after three days were assessed using STXM. The hydration process and subsequent formation of calcium sulfate in the C3A/gypsum systems were identified through the changes in the LIII edge fine structure for Calcium. The results also show greater Ca LII binding energies between hydrated samples with different gypsum contents. Conversely, the hydrated samples from the cubic and orthorhombic C3A at the same amount of gypsum exhibited strong morphological differences but similar chemical environments.

  15. Medical students’ attitudes toward gay men

    OpenAIRE

    Matharu, Kabir; Kravitz, Richard L; McMahon, Graham T; Wilson, Machelle D; Fitzgerald, Faith T

    2012-01-01

    Abstract Background Healthcare providers’ attitudes toward sexual minorities influence patient comfort and outcomes. This study characterized medical student attitudes toward gay men, focusing on behavior, personhood, gay civil rights, and male toughness. Methods A cross-sectional web-based anonymous survey was sent to medical students enrolled at the University of California, Davis (N = 371) with a response rate of 68%. Results Few respondents expressed negative attitudes toward gay men or w...

  16. Characterization of un-hydrated and hydrated BioAggregate™ and MTA Angelus™.

    Science.gov (United States)

    Camilleri, J; Sorrentino, F; Damidot, D

    2015-04-01

    high calcium ion release early, which was maintained over the 28-day period as opposed to MTA Angelus, which demonstrated low early calcium ion release which increased as the material aged. The mineralogical composition of BioAggregate was different to MTA Angelus. As opposed to MTA Angelus, BioAggregate did not contain aluminium and contained additives such as calcium phosphate and silicon dioxide. As a consequence, BioAggregate reacted more slowly and formation of calcium hydroxide and leaching of calcium ions in solution were not evident as the material aged. The additives in BioAggregate modify the kinetics and the end products of hydration. Although newer generation tricalcium silicate-based materials contain similar constituents to MTA, they do not undergo the same setting reactions, and thus, their clinical performance will not be comparable to that of MTA.

  17. Alcohol cosurfactants in hydrate antiagglomeration.

    Science.gov (United States)

    York, J Dalton; Firoozabadi, Abbas

    2008-08-28

    Because of availability, as well as economical and environmental considerations, natural gas is projected to be the premium fuel of the 21st century. Natural gas production involves risk of the shut down of onshore and offshore operations because of blockage from hydrates formed from coproduced water and hydrate-forming species in natural gas. Industry practice has been usage of thermodynamic inhibitors such as alcohols often in significant amounts, which have undesirable environmental and safety impacts. Thermodynamic inhibitors affect bulk-phase properties and inhibit hydrate formation. An alternative is changing surface properties through usage of polymers and surfactants, effective at 0.5 to 3 weight % of coproduced water. One group of low dosage hydrate inhibitors (LDHI) are kinetic inhibitors, which affect nucleation rate and growth. A second group of LDHI are antiagglomerants, which prevent agglomeration of small hydrate crystallites. Despite great potential, work on hydrate antiagglomeration is very limited. This work centers on the effect of small amounts of alcohol cosurfactant in mixtures of two vastly different antiagglomerants. We use a model oil, water, and tetrahydrofuran as a hydrate-forming species. Results show that alcohol cosurfactants may help with antiagglomeration when traditional antiagglomerants alone are ineffective. Specifically, as low as 0.5 wt. % methanol cosurfactant used in this study is shown to be effective in antiagglomeration. Without the cosurfactant there will be agglomeration independent of the AA concentration. To our knowledge, this is the first report of alcohol cosurfactants in hydrate antiagglomerants. It is also shown that a rhamnolipid biosurfactant is effective down to only 0.5 wt. % in such mixtures, yet a quaternary ammonium chloride salt, i. e., quat, results in hydrate slurries down to 0.01 wt. %. However, biochemical surfactants are less toxic and biodegradable, and thus their use may prove beneficial even if at

  18. Thermal properties of methane hydrate by experiment and modeling and impacts upon technology

    Energy Technology Data Exchange (ETDEWEB)

    Warzinski, R.P.; Gamwo, I.K.; Rosenbaum, E.J. [United States Dept. of Energy, Pittsburgh, PA (United States). National Energy Technology Laboratory; Myshakin, E.M. [NETL Support Contractor, South Park, PA (United States); Jiang, H.; Jordan, K.D. [Pittsburgh Univ., Pittsburgh, PA (United States). Dept. of Chemistry; English, N.J. [Dublin University College, Dublin (Ireland). Conway Inst. of Biomolecular and Biomedical Research, Centre for Synthesis and Chemical Biology; Shaw, D.W. [Geneva College, Beaver Falls, PA (United States). Dept. of Engineering

    2008-07-01

    The current hydrate research at the National Energy Technology Laboratory (NETL) involves both experimental and theoretical work on developing models and methods for predicting the behaviour of gas hydrates in their natural environment under production of climate change scenarios. The modeling efforts include both fundamental and reservoir scale simulations and economic modeling. The thermal properties of methane hydrate are important for hydrate production, seafloor stability and climate change scenarios. A new experimental technique and advanced molecular dynamics simulation (MDS) have determined the thermal properties of pure methane hydrate under conditions similar to naturally occurring hydrate-bearing sediments. The thermal conductivity and thermal diffusivity values of low-porosity methane hydrate formed in the laboratory were measured using an innovative single-sided, Transient Plane Source (TPS) technique. The results were in good agreement with results from an equilibrium MDS method using in-plane polarization of the water molecules. MDS was also performed using a non-equilibrium model with a fully polarizable force field for water. The Tough+Hydrate reservoir simulator was also used to evaluate the impact of thermal conductivity on gas production from a hydrate-bearing reservoir. 42 refs., 1 tab., 5 figs.

  19. CO2 injection into submarine, CH4-hydrate bearing sediments: Parameter studies towards the development of a hydrate conversion technology

    Science.gov (United States)

    Deusner, Christian; Bigalke, Nikolaus; Kossel, Elke; Haeckel, Matthias

    2013-04-01

    In the recent past, international research efforts towards exploitation of submarine and permafrost hydrate reservoirs have increased substantially. Until now, findings indicate that a combination of different technical means such as depressurization, thermal stimulation and chemical activation is the most promising approach for producing gas from natural hydrates. Moreover, emission neutral exploitation of CH4-hydrates could potentially be achieved in a combined process with CO2 injection and storage as CO2-hydrate. In the German gas hydrate initiative SUGAR, a combination of experimental and numerical studies is used to elucidate the process mechanisms and technical parameters on different scales. Experiments were carried out in the novel high-pressure flow-through system NESSI (Natural Environment Simulator for sub-Seafloor Interactions). Recent findings suggest that the injection of heated, supercritical CO2 is beneficial for both CH4 production and CO2 retention. Among the parameters tested so far are the CO2 injection regime (alternating vs. continuous injection) and the reservoir pressure / temperature conditions. Currently, the influence of CO2 injection temperature is investigated. It was shown that CH4 production is optimal at intermediate reservoir temperatures (8 ° C) compared to lower (2 ° C) and higher temperatures (10 ° C). The reservoir pressure, however, was of minor importance for the production efficiency. At 8 ° C, where CH4- and CO2-hydrates are thermodynamically stable, CO2-hydrate formation appears to be slow. Eventual clogging of fluid conduits due to CO2-rich hydrate formation force open new conduits, thereby tapping different regions inside the CH4-hydrate sample volume for CH4gas. In contrast, at 2 ° C immediate formation of CO2-hydrate results in rapid and irreversible obstruction of the entire pore space. At 10 ° C pure CO2-hydrates can no longer be formed. Consequently the injected CO2 flows through quickly and interaction with

  20. The relationships between sense of belonging to the gay community, body image dissatisfaction, and self-esteem among Australian gay men.

    Science.gov (United States)

    Kousari-Rad, Pantea; McLaren, Suzanne

    2013-01-01

    Body image dissatisfaction has been linked to belonging to the gay community and poor self-esteem among gay men. This study was designed to explore the applicability of a moderation model and a mediation model in explaining the relations between sense of belonging to the gay community, body image dissatisfaction and self-esteem among 90 self-identified Australian gay men. Participants completed the psychological subscale of the Sense of Belonging Instrument, the Body Satisfaction Scale, and the Rosenberg Self-Esteem Scale. Results supported the moderation model; the relation between body image dissatisfaction and self-esteem was found to be statistically significant only at average and high levels of belonging to the gay community. The mediation model was also supported; body image dissatisfaction partially mediated the sense of belonging-self-esteem relation. Educating gay men and health professionals about the possible negative outcomes of "belonging" to an appearance-oriented community is important.

  1. Numerical Simulations for Enhanced Methane Recovery from Gas Hydrate Accumulations by Utilizing CO2 Sequestration

    Science.gov (United States)

    Sridhara, Prathyusha

    In 2013, the International Energy Outlook (EIA, 2013) projected that global energy demand will grow by 56% between 2010 and 2040. Despite strong growth in renewable energy supplies, much of this growth is expected to be met by fossil fuels. Concerns ranging from greenhouse gas emissions and energy security are spawning new interests for other sources of energy including renewable and unconventional fossil fuel such as shale gas and oil as well as gas hydrates. The production methods as well as long-term reservoir behavior of gas hydrate deposits have been under extensive investigation. Reservoir simulators can be used to predict the production potentials of hydrate formations and to determine which technique results in enhanced gas recovery. In this work, a new simulation tool, Mix3HydrateResSim (Mix3HRS), which accounts for complex thermodynamics of multi-component hydrate phase comprised of varying hydrate solid crystal structure, is used to perform the CO2-assisted production technique simulations from CH4 hydrate accumulations. The simulator is one among very few reservoir simulators which can simulate the process of CH4 substitution by CO2 (and N2 ) in the hydrate lattice. Natural gas hydrate deposits around the globe are categorized into three different classes based on the characteristics of the geological sediments present in contact with the hydrate bearing deposits. Amongst these, the Class 2 hydrate accumulations predominantly confirmed in the permafrost and along seashore, are characterized by a mobile aqueous phase underneath a hydrate bearing sediment. The exploitation of such gas hydrate deposits results in release of large amounts of water due to the presence of permeable water-saturated sediments encompassing the hydrate deposits, thus lowering the produced gas rates. In this study, a suite of numerical simulation scenarios with varied complexity are considered which aimed at understanding the underlying changes in physical, thermodynamic and

  2. The Prevalence of Lisping in Gay Men

    Science.gov (United States)

    Van Borsel, John; De Bruyn, Els; Lefebvre, Evelien; Sokoloff, Anouschka; De Ley, Sophia; Baudonck, Nele

    2009-01-01

    This study evaluated the stereotype that gay men lisp. Two clinicians who were unaware of the specific purpose of the study and the populations involved judged randomized audio-recordings of 175 gay males, 100 heterosexual males and 100 heterosexual females for the presence of lisping during reading of a standardized text. In the gay males a…

  3. Personality of Polish gay men and women

    Directory of Open Access Journals (Sweden)

    Marcin Kwiatkowski

    2015-12-01

    Full Text Available Background Sexuality is a part of one’s identity and personality that is shaped under the influence of biological and environmental factors and interactions with society. The results of research conducted so far and concerning the personality traits of gay men and women are not consistent, and only a small number of them concern the Polish population. Hence the objective of the present research was to provide personality profiles of men and women with different sexual orientations. Participants and procedure The participants (N = 346 included 84 gay women, 82 gay men, 95 heterosexual women and 85 heterosexual men. The following measures were used: a survey developed by the author, the Kinsey Scale, the EPQ-R (Eysenck Personality Questionnaire Revised adapted by Brzozowski and Drwal (1995, and the Sixteen-factor Personality Questionnaire of Cattell adapted by Nowakowska (1970. Results The results support the hypothesis that gay women and heterosexual men share similar personality traits, while gay men have more diverse traits, similar to the traits typical for heterosexual women and men. In particular, personalities of gay men are described by such traits as progressive attitude, independence, or willingness to take risks, which means traits linked to factor Q1. The highest values of that factor are observable in the case of gay men, as compared to gay women, and also in comparison with heterosexual men and women. Conclusions Sexual orientation is responsible for differences in personality traits of the studied group to a greater extent than their biological sex.

  4. Sitges (Catalunya y el carnaval gay: el turismo

    Directory of Open Access Journals (Sweden)

    Lacaba Gutiérrez, José Juan

    2004-01-01

    Full Text Available In this paper, I explain the development of a tourist village in the Catalonian coast (northeast of Spain as a gay destination during carnival times during the month February. My intention is to include my reflections in this paper in the symbolic - cognitive studies about tourism and I want also to reflect about the idea of the constructions in gay culture of different places all around the world of leisure or/and pilgrimage. Sitges is a scale gay destination really knowledge in Western Europe during the hole year, but during carnival times, it's convert in a gay pilgrimage in different ways and there is have been crated during those last years gays places of leisure in the village that make me create the idea of the existence of a gay Carnival in Sitges Carnival. Because we cannot consider the gay carnival independent of what I call Sitges Carnival, I explain also the development and the historical conflicts between those two carnivals, and how those separate spaces have been created

  5. Hydrate-CASM for modeling Methane Hydrate-Bearing Sediments

    Science.gov (United States)

    De La Fuente Ruiz, M.; Vaunat, J.; Marin Moreno, H.

    2017-12-01

    A clear understanding of the geomechanical behavior of methane hydrate-bearing sediments (MHBS) is crucial to assess the stability of the seafloor and submarine infrastructures to human and natural loading changes. Here we present the Hydrate-CASM, a new elastoplastic constitutive model to predict the geomechanical behavior of MHBS. Our model employs the critical state model CASM (Clay and Sand Model) because of its flexibility in describing the shape of the yield surface and its proven ability to predict the mechanical behavior of sands, the most commercially viable hydrate reservoirs. The model considers MHBS as a deformable elastoplastic continuum, and hydrate-related changes in the stress-strain behavior are predicted by a densification mechanism. The densification attributes the mechanical contribution of hydrate to; a reduction of the available void ratio; a decrease of the swelling line slope; and an increase of the volumetric yield stress. It is described by experimentally derived physical parameters except from the swelling slope coefficient that requires empirical calibration. The Hydrate-CASM is validated against published triaxial laboratory tests performed at different confinement stresses, hydrate saturations, and hydrate morphologies. During the validation, we focused on capturing the mechanical behavior of the host sediment and consider perturbations of the sediment's mechanical properties that could result from the sample preparation. Our model successfully captures the experimentally observed influence of hydrate saturation in the magnitude and trend of the stiffness, shear strength, and dilatancy of MHBS. Hence, we propose that hydrate-related densification changes might be a major factor controlling the geomechanical response of MHBS.

  6. Preliminary assessment of the waveform inversion method for interpretation of cross-well seismic data from the thermal production test, JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T. [Nagoya Univ., Nagoya (Japan). Research Center for Seismology and Volcanology; Shimizu, S. [Japan National Oil Co., Chiba (Japan); Asakawa, E. [JGI Inc., Tokyo (Japan); Kamei, R.; Matsuoka, T. [Kyoto Univ., Kyoto (Japan). Dept. of Civil and Earth Resources Engineering

    2005-07-01

    The JAPEX/JNOC/GSC et al. Mallik 3L-38 and 4L-38 test wells were subjected to repeated cross-well seismic surveys before and during the gas production test from the gas-hydrate-bearing layer at a depth of about 905 to 920 m. High-resolution velocity images in the gas-hydrate-bearing layer were obtained using the frequency-domain nonlinear waveform inversion method. An acoustic waveform inversion method was used along with the frequency-domain approach in order to detect the change in acoustic properties of the gas-hydrate-bearing layer resulting from gas production. The layered structures with small lateral heterogeneities were reconstructed by tomography analysis of preprocessed waveform data using a smaller number of source-receiver pairs. Preliminary results reveal high velocity and very high attenuation in the gas-hydrate-bearing layers. No obvious velocity decreases were noted. Information for further detailed processing was also gathered.

  7. Can additive measures add to an intersectional understanding? Experiences of gay and ethnic discrimination among HIV-positive Latino gay men.

    Science.gov (United States)

    Reisen, Carol A; Brooks, Kelly D; Zea, Maria Cecilia; Poppen, Paul J; Bianchi, Fernanda T

    2013-04-01

    The current study investigated a methodological question of whether traditional, additive, quantitative data can be used to address intersectional issues, and illustrated such an approach with a sample of 301 HIV-positive, Latino gay men in the United States. Participants were surveyed using A-CASI. Hierarchical logistic set regression investigated the role of sets of variables reflecting demographic characteristics, gender nonconformity, and gay and ethnic discrimination in relation to depression and gay collective identity. Results showed the discrimination set was related to depression and to gay collective identity, as was gender nonconformity. Follow-up logistic regression showed that both types of discrimination were associated with greater depression, but gender nonconformity was not. Gay discrimination and gender nonconformity were positively associated with gay collective identity, whereas ethnic discrimination was negatively associated. Results are discussed in terms of the use of traditional quantitative data as a potential means of understanding intersectional issues, as well as of contributing to knowledge about individuals facing multiple structural inequalities.

  8. Hydrates plugs dissociation in pipelines; Dissociation des bouchons d'hydrates de gaz dans les conduites petrolieres sous-marines

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Hong, D.

    2005-03-15

    Natural gas hydrates plugs cause problems during drilling, well operations, production, transportation and processing of oil and gas. Especially, it is a very serious problem in off-shore oil transportation where low temperature and high pressure become more and more favourable to gas hydrate formation as the new production wells are more and more deeper. Up to now, although many studies have been developed concerning the possibility of preventing pipe plugging, there is limited information in open literature on hydrate plugs dissociation and all models in literature are numerically complicated. In this study, hydrate plugs are formed from water in n-dodecane mixture with addition of a dispersant E102B in two different experimental apparatus in order to obtain hydrates plugs with different sizes (diameter of 7, 10.75 and 12 cm). Then, the plugs are dissociated by the method of two-sided depressurization. In this paper, we propose a numerical model which describes the dissociation of gas hydrate plugs in pipelines. The numerical model, which is constructed for cylindrical coordinates and for two-sided pressurization, is based on enthalpy method. We present also an approximate analytical model which has an average error 2.7 % in comparison with the numerical model. The excellent agreement between our experimental results, literature data and the two models shows that the models give a good prediction independently of the pipeline diameter, plug porosity and gas. The simplicity of the analytical model will make it easier in industrial applications. (author)

  9. Just Kill Me When I’m 50: Impact of Gay American Culture on Young Gay Men’s Perceptions of Aging

    Directory of Open Access Journals (Sweden)

    Rob Jay Fredericksen

    2010-04-01

    Full Text Available Young gay men’s negative perceptions of growing older have been indicated in prior research [Bergling, 2004; Jones & Pugh, 2005; Cohler & Galatzer-Levy, 2000]. A recent resurgence of HIV infection rates among young gay men [Mitsch et al, 2008] calls into question whether these negative perceptions contribute to a lack of future-oriented health investments; i.e., a “live for now” outlook. Strength of future orientation has repeatedly predicted risk aversion [McCabe & Barnett, 2000], hence, it is of great social and public health value to ask: what does aging mean to today’s youngest generation of gay men? How do cultural norms in the gay community inform how today’s young gay men imagine growing older? This research explores these questions.

  10. How Like Perceives Like: Gay People on "Gaydar".

    Science.gov (United States)

    Barton, Bernadette

    2015-01-01

    When lacking explicit knowledge of someone's sexual orientation, gay people commonly assess the likelihood that another is gay using their "gaydar." The term gaydar is a playful mix of the word gay with radar, suggesting that one can sense, intuit, or perceive some set of characteristics in another that signal a shared minority status. While commonly mentioned, the exact criteria a gay person uses when employing their gaydar are little discussed. Drawing methodologically on a series of five focus groups of self-identified lesbians and gay men, this study explores the physical, visual, energetic, and conversational cues gay people consider when they employ the trope of gaydar. Specifically, interview subjects most often described their gaydar as triggered by the following elements: physical presentation, including mannerisms, dress, and voice; interactions, especially eye contact; a presence or absence of certain conversational social norms; and, intangibly, as a kind of energetic exchange.

  11. Association of Gay and Lesbian Psychiatrists

    Science.gov (United States)

    ... Awards AGLP News Newsletter Archives Education Journal of Gay and Lesbian Mental Health GAP LGBT Online Curriculum ... an End to Harmful ‘Religious Freedom’ Laws...> WPA: Gay “Cures” Are Harmful And Don’t Work See ...

  12. Portland cement hydration in the presence of admixtures: black gram pulse and superplasticizer

    Directory of Open Access Journals (Sweden)

    Viveka Nand Dwivedi

    2008-12-01

    Full Text Available Effect of admixtures such as black gram pulse (BGP and sulfonated naphthalene based superplasticizer (SP on the hydration of Portland cement has been studied. The hydration characteristics of OPC in the presence of BGP and SP were studied with the help of non evaporable water content determinations, calorimetric method, Mössbauer spectroscopic and atomic force microscopic techniques. Results have shown that both BGP and SP get adsorbed at the surface of cement and its hydration products. The hydration of Portland cement is retarded in the presence of both the admixtures and nanosize hydration products are formed.

  13. Numerical modeling of the simulated gas hydrate production test at Mallik 2L-38 in the pilot scale pressure reservoir LARS - Applying the "foamy oil" model

    Science.gov (United States)

    Abendroth, Sven; Thaler, Jan; Klump, Jens; Schicks, Judith; Uddin, Mafiz

    2014-05-01

    In the context of the German joint project SUGAR (Submarine Gas Hydrate Reservoirs: exploration, extraction and transport) we conducted a series of experiments in the LArge Reservoir Simulator (LARS) at the German Research Centre of Geosciences Potsdam. These experiments allow us to investigate the formation and dissociation of hydrates at large scale laboratory conditions. We performed an experiment similar to the field-test conditions of the production test in the Mallik gas hydrate field (Mallik 2L-38) in the Beaufort Mackenzie Delta of the Canadian Arctic. The aim of this experiment was to study the transport behavior of fluids in gas hydrate reservoirs during depressurization (see also Heeschen et al. and Priegnitz et al., this volume). The experimental results from LARS are used to provide details about processes inside the pressure vessel, to validate the models through history matching, and to feed back into the design of future experiments. In experiments in LARS the amount of methane produced from gas hydrates was much lower than expected. Previously published models predict a methane production rate higher than the one observed in experiments and field studies (Uddin et al. 2010; Wright et al. 2011). The authors of the aforementioned studies point out that the current modeling approach overestimates the gas production rate when modeling gas production by depressurization. They suggest that trapping of gas bubbles inside the porous medium is responsible for the reduced gas production rate. They point out that this behavior of multi-phase flow is not well explained by a "residual oil" model, but rather resembles a "foamy oil" model. Our study applies Uddin's (2010) "foamy oil" model and combines it with history matches of our experiments in LARS. Our results indicate a better agreement between experimental and model results when using the "foamy oil" model instead of conventional models of gas flow in water. References Uddin M., Wright J.F. and Coombe D

  14. Identity and Sex: Concurent Aspects of Gay Tourism

    OpenAIRE

    Monterrubio, J. Carlos

    2008-01-01

    The present article aims to contribute to the recognition of two relevant aspects in gay travel; identity and sex. The paper explores the existing published work related to the relationships between tourism, gay men and identity. It concludes that the issue of identity commonly plays a crucial role as a travel reason in gay tourism. Also, it analyses the research evidence to suggest that sex is a frequently-present phenomenon in gay travel. By critically analysing the available research, the ...

  15. Predicting the Impact of Multiwalled Carbon Nanotubes on the Cement Hydration Products and Durability of Cementitious Matrix Using Artificial Neural Network Modeling Technique

    Directory of Open Access Journals (Sweden)

    Babak Fakhim

    2013-01-01

    Full Text Available In this study the feasibility of using the artificial neural networks modeling in predicting the effect of MWCNT on amount of cement hydration products and improving the quality of cement hydration products microstructures of cement paste was investigated. To determine the amount of cement hydration products thermogravimetric analysis was used. Two critical parameters of TGA test are PHPloss and CHloss. In order to model the TGA test results, the ANN modeling was performed on these parameters separately. In this study, 60% of data are used for model calibration and the remaining 40% are used for model verification. Based on the highest efficiency coefficient and the lowest root mean square error, the best ANN model was chosen. The results of TGA test implied that the cement hydration is enhanced in the presence of the optimum percentage (0.3 wt% of MWCNT. Moreover, since the efficiency coefficient of the modeling results of CH and PHP loss in both the calibration and verification stages was more than 0.96, it was concluded that the ANN could be used as an accurate tool for modeling the TGA results. Another finding of this study was that the ANN prediction in higher ages was more precise.

  16. Offsetting Risks: High School Gay-Straight Alliances and Lesbian, Gay, Bisexual, and Transgender (LGBT) Youth

    Science.gov (United States)

    Heck, Nicholas C.; Flentje, Annesa; Cochran, Bryan N.

    2011-01-01

    Lesbian, gay, bisexual, and transgender (LGBT) youth are at risk for engaging in negative health behaviors and for experiencing at-school victimization. Specific benefits of attending a high school with a gay-straight alliance (GSA), including lower levels of suicidality, have been published; however, it is unclear whether GSAs are related to…

  17. An international effort to compare gas hydrate reservoir simulators

    Energy Technology Data Exchange (ETDEWEB)

    Wilder, J.W. [Akron Univ., Akron, OH (United States). Dept. of Theoretical and Applied Math; Moridis, G.J. [California Univ., Berkely, CA (United States). Earth Sciences Div., Lawrence Berkely National Lab.; Wilson, S.J. [Ryder Scott Co., Denver, CO (United States); Kurihara, M. [Japan Oil Engineering Co. Ltd., Tokyo (Japan); White, M.D. [Pacific Northwest National Laboratory Hydrology Group, Richland, WA (United States); Masuda, Y. [Tokyo Univ., Tokyo (Japan). Dept. of Geosystem Engineering; Anderson, B.J. [National Energy Technology Lab., Morgantown, WV (United States)]|[West Virginia Univ., Morgantown, WV (United States). Dept. of Chemical Engineering; Collett, T.S. [United States Geological Survey, Denver, CO (United States); Hunter, R.B. [ASRC Energy Services, Anchorage, AK (United States); Narita, H. [National Inst. of Advanced Industrial Science and Technology, MEthane hydrate Research Lab., Sapporo (Japan); Pooladi-Darvish, M. [Fekete Associates Inc., Calgary, AB (Canada); Rose, K.; Boswell, R. [National Energy Technology Lab., Morgantown, WV (United States)

    2008-07-01

    In this study, 5 different gas hydrate production scenarios were modeled by the CMG STARS, HydateResSim, MH-21 HYDRES, STOMP-HYD and the TOUGH+HYDRATE reservoir simulators for comparative purposes. The 5 problems ranged in complexity from 1 to 3 dimensional with radial symmetry, and in horizontal dimensions of 20 meters to 1 kilometer. The scenarios included (1) a base case with non-isothermal multi-fluid transition to equilibrium, (2) a base case with gas hydrate (closed-domain hydrate dissociation), (3) dissociation in a 1-D open domain, (4) gas hydrate dissociation in a one-dimensional radial domain, similarity solutions, (5) gas hydrate dissociation in a two-dimensional radial domain. The purpose of the study was to compare the world's leading gas hydrate reservoir simulators in an effort to improve the simulation capability of experimental and naturally occurring gas hydrate accumulations. The problem description and simulation results were presented for each scenario. The results of the first scenario indicated very close agreement among the simulators, suggesting that all address the basics of mass and heat transfer, as well as overall process of gas hydrate dissociation. The third scenario produced the initial divergence among the simulators. Other differences were noted in both scenario 4 and 5, resulting in significant corrections to algorithms within several of the simulators. The authors noted that it is unlikely that these improvements would have been identified without this comparative study due to a lack of real world data for validation purposes. It was concluded that the solution for gas hydrate production involves a combination of highly coupled fluid, heat and mass transport equations combined with the potential for formation or disappearance of multiple solid phases in the system. The physical and chemical properties of the rocks containing the gas hydrate depend on the amount of gas hydrate present in the system. Each modeling and

  18. Reported Effects of Masculine Ideals on Gay Men.

    Science.gov (United States)

    Sánchez, Francisco J; Greenberg, Stefanie T; Liu, William Ming; Vilain, Eric

    2009-01-01

    This exploratory study used consensual qualitative research methodology (Hill et al., 2005) to analyze what gay men associate with masculinity and femininity, how they feel masculine ideals affect their self-image, and how masculine ideals affect their same-sex relationships. Written responses were collected from 547 self-identified gay men in the U.S. via an Internet-based survey. Findings supported previous reports that perceptions of gender roles among gay men appear based on masculine and feminine stereotypes. Additionally, more adverse versus positive effects on self-image and same-sex romantic relationships were reported including difficulty being emotional and affectionate, pressure to be physically attractive, and pressure to appear masculine in order to be accepted by society and to be seen as desirable by other gay men. While research on gay men's experience with masculinity continues, psychologists should consider the possible influence of traditional masculine ideals when conceptualizing their gay male clients.

  19. India National Gas Hydrate Program Expedition 02 Technical Contributions

    Science.gov (United States)

    Collett, T. S.; Kumar, P.; Shukla, K. M.; Nagalingam, J.; Lall, M. V.; Yamada, Y.; Schultheiss, P. J.; Holland, M.; Waite, W. F.

    2017-12-01

    The National Gas Hydrate Program Expedition 02 (NGHP-02) was conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India. The primary objective of this expedition was the exploration and discovery of highly saturated gas hydrate occurrences in sand reservoirs that would be targets of future production testing. The first 2 months of the expedition were dedicated to logging while drilling (LWD) operations with a total of 25 holes being drilled and logged. The next 3 months were dedicated to coring operations at 10 of the most promising sites. NGHP-02 downhole logging, coring and formation pressure testing have confirmed the presence of large, highly saturated, gas hydrate accumulations in coarse-grained sand-rich depositional systems throughout the Krishna-Godavari Basin within the regions defined during NGHP-02 as Area-B, Area-C, and Area-E. The nature of the discovered gas hydrate occurrences closely matched pre-drill predictions, confirming the project developed depositional models for the sand-rich depositional facies in the Krishna-Godavari and Mahanadi Basins. The existence of a fully developed gas hydrate petroleum system was established in Area-C of the Krishna-Godavari Basin with the discovery of a large slope-basin interconnected depositional system, including a sand-rich, gas-hydrate-bearing channel-levee prospect at Sites NGHP-02-08 and -09. The acquisition of closely spaced LWD and core holes in the Area-B L1 Block gas hydrate accumulation have provided one of the most complete three-dimensional petrophysical-based views of any known gas hydrate reservoir system in the world. It was concluded that Area-B and Area-C in the area of the greater Krishna-Godavari Basin contain important world-class gas hydrate accumulations and represent ideal sites for consideration of future gas hydrate production testing.

  20. Know about Gays and Lesbians.

    Science.gov (United States)

    Hyde, Margaret O.; Forsyth, Elizabeth H.

    Homosexuality has emerged as a major issue making headlines across the country, including initiatives, which have been put on state and local ballots, that limit or guarantee the civil rights of gays and lesbians. This book, designed as a guide for juveniles, separates fact from fiction about gays and lesbians and explains homosexuality in clear,…

  1. Structural and hydration properties of amorphous tricalcium silicate

    International Nuclear Information System (INIS)

    Mori, K.; Fukunaga, T.; Shiraishi, Y.; Iwase, K.; Xu, Q.; Oishi, K.; Yatsuyanagi, K.; Yonemura, M.; Itoh, K.; Sugiyama, M.; Ishigaki, T.; Kamiyama, T.; Kawai, M.

    2006-01-01

    Mechanical milling was carried out to synthesize amorphous tricalcium silicate (Ca 3 SiO 5 ) sample, where Ca 3 SiO 5 is the most principal component of Portland cement. The partial phase transformation from the crystalline to the amorphous state was observed by X-ray and neutron diffractions. Moreover, it was found that the structural distortion on the Ca-O correlation exists in the milled Ca 3 SiO 5 . The hydration of the milled Ca 3 SiO 5 with D 2 O proceeds as follows: the formation of hydration products such as Ca(OD) 2 rapidly occurs in the early hydration stage, and then proceeds slowly after about 15 h. The induction time for the hydration of the milled Ca 3 SiO 5 is approximately one half shorter than that for the hydration of the unmilled one. This result means that the mechanical milling brings about the chemical activity of Ca 3 SiO 5 for hydration, and may be particularly useful for increasing the reactivity in the early hydration stage

  2. Ab initio modelling of methane hydrate thermophysical properties.

    Science.gov (United States)

    Jendi, Z M; Servio, P; Rey, A D

    2016-04-21

    The key thermophysical properties of methane hydrate were determined using ab initio modelling. Using density functional theory, the second-order elastic constants, heat capacity, compressibility, and thermal expansion coefficient were calculated. A wide and relevant range of pressure-temperature conditions were considered, and the structures were assessed for stability using the mean square displacement and radial distribution functions. Methane hydrate was found to be elastically isotropic with a linear dependence of the bulk modulus on pressure. Equally significant, multi-body interactions were found to be important in hydrates, and water-water interactions appear to strongly influence compressibility like in ice Ih. While the heat capacity of hydrate was found to be higher than that of ice, the thermal expansion coefficient was significantly lower, most likely due to the lower rigidity of hydrates. The mean square displacement gave important insight into stability, heat capacity, and elastic moduli, and the radial distribution functions further confirmed stability. The presented results provide a much needed atomistic thermoelastic characterization of methane hydrates and are essential input for the large-scale applications of hydrate detection and production.

  3. Addiction and recovery in gay and lesbian persons

    National Research Council Canada - National Science Library

    Kus, Robert J

    1995-01-01

    .... Addiction and Recovery is a vital resourcefor anyone providing servicesfor gay, lesbian, and bisexualclients. Rik Isensee,LCSW Author, LOVE BEIWEEN MEN, and GROWING UP GAY IN A DYSFUNCTIONAL FAMILYMore pre-publication REVIEWS,COMMENTARIES, EVALUATIONS . .. "A ddiction and Recovery in Gay and Lesbian Persons" is an excellentcollection of multifa...

  4. The only gay in the village? Everyday life of gays and lesbians in rural Slovenia.

    Science.gov (United States)

    Kuhar, Roman; Svab, Alenka

    2014-01-01

    The article deals with the comparison of the characteristics, experiences, and perceptions of everyday life of gays and lesbians living in rural and urban areas of Slovenia. We focus on the following thematic aspects: (1) coming out; (2) intimate partnerships; (3) the access and the use of gay infrastructure; and (4) violence against gays and lesbians. The article also addresses and discusses the urban/rural divide as a Western construct that might not be completely applicable to other social and cultural contexts. Taking Slovenia as an example, this article questions the self-evidence of rural/urban divide as an analytical concept. On the basis of our research, we conclude that this concept requires continuous revisions and reinterpretations in a concrete social and cultural context(s). The characteristics of gay and lesbian everyday life either in rural or in urban context in Slovenia lead to the conclusion that even within a specific social and cultural context, the concept of urban/rural divide should be used carefully, taking into account complexities of everyday lives and various factors that influence them.

  5. Calcium Aluminate Cement Hydration Model

    Directory of Open Access Journals (Sweden)

    Matusinović, T.

    2011-01-01

    Full Text Available Calcium aluminate cement (AC is a very versatile special cement used for specific applications. As the hydration of AC is highly temperature dependent, yielding structurally different hydration products that continuously alter material properties, a good knowledge of thermal properties at early stages of hydration is essential. The kinetics of AC hydration is a complex process and the use of single mechanisms models cannot describe the rate of hydration during the whole stage.This paper examines the influence of temperature (ϑ=5–20 °C and water-to-cement mass ratio (mH /mAC = 0.4; 0.5 and 1.0 on hydration of commercial iron-rich AC ISTRA 40 (producer: Istra Cement, Pula, Croatia, which is a part of CALUCEM group, Figs 1–3. The flow rate of heat generation of cement pastes as a result of the hydration reactions was measured with differential microcalorimeter. Chemically bonded water in the hydrated cement samples was determined by thermo-gravimetry.Far less heat is liberated when cement and water come in contact for the first time, Fig. 1, than in the case for portland cement (PC. Higher water-to-cement ratio increases the heat evolved at later ages (Fig. 3 due to higher quantity of water available for hydration. A significant effect of the water-to-cement ratio on the hydration rate and hydration degree showed the importance of water as being the limiting reactant that slows down the reaction early. A simplified stoichiometric model of early age AC hydration (eq. (8 based on reaction schemes of principal minerals, nominally CA, C12A7 and C4AF (Table 1, was employed. Hydration kinetics after the induction period (ϑ < 20 °C had been successfully described (Fig. 4 and Table 2 by a proposed model (eq. (23 which simultaneously comprised three main mechanisms: nucleation and growth, interaction at phase boundary, and mass transfer. In the proposed kinetic model the nucleation and growth is proportional to the amount of reacted minerals (eq

  6. Le problème des hydrates dans le contexte de la production et du transport polyphasiques des pétroles bruts et des gaz naturels. Deuxième partie : les solutions possibles aux difficultés d'exploitation générées par les hydrates Hydrates Problem Within the Framework of Multiphase Production and Transport of Crude Oils and Natural Gases. Part Two: Possible Solutions to Exploitation Difficulties Generated by Hydrates

    Directory of Open Access Journals (Sweden)

    Behar E.

    2006-11-01

    Full Text Available L'exploitation en mer des gisements de combustibles fossiles fluides a amplifié le besoin d'accroître nos connaissances sur les hydrates qui sont susceptibles de boucher les installations de production, de traitement et de transport. La première partie rappelait la structure moléculaire des hydrates I, Il et H et décrivait ensuite succinctement l'analyse physico-chimique de leur formation, tant sur les plans thermodynamique que cinétique. Dans cette deuxième partie, les remèdes possibles aux problèmes rencontrés par les compagnies opératrices sont indiqués, essentiellement les inhibiteurs thermodynamiques classiques tels que les alcools ou les sels qui diminuent la température de formation des hydrates, et les additifs dispersants qui évitent la croissance et/ou l'agglomération des cristaux. Pour terminer, une boucle pilote de circulation originale est présentée, ses caractéristiques qui permettent la validation des additifs dispersants dans des conditions hydrodynamiques et physico-chimiques représentatives étant soulignées. Offshore exploitation of fossil fluid fuels has emphasized the need of improving our knowledge on hydrates which can plug production, treatment and transport facilities. The first part recalled the molecular structure of I, II and H hydrates, then the physical-chemistry of their formation was briefly reviewed from both the thermodynamic and the kinetic points of view. In this second part, the possible remedies to the problems met by operating companies are described, mainly classical thermodynamic inhibitors such as alcohols or salts which decrease the hydrates formation temperature, and dispersant additives which avoid crystals growth and/or agglomeration. At last an original circulation loop at pilot scale is presented, its characteristics which allow the testing of dispersant additives under representative hydrodynamic and physico-chemical conditions being outlined.

  7. Marginalization among the marginalized: gay men's anti-effeminacy attitudes.

    Science.gov (United States)

    Taywaditep, K J

    2001-01-01

    Contemporary research has shown that a significant portion of gay men have traits, interests, occupations, and behaviors that are consistent with the stereotype of gay men as effeminate, androgynous, or unmasculine. A great number of gay men exhibit gender nonconformity during childhood; most, however, "defeminize" during adolescence, possibly in response to stigmatization and society's gender-role prescription. Only a relatively small percentage of gay men continue to be gender-nonconforming in their adulthood, often at a price, as they also tend to have lower psychological well-being. Although gay culture historically appreciated camp and drag, which subvert the gender-based power hierarchy and celebrate gender nonconformity, anti-effeminacy prejudice is widespread among gay men. Ironically, gender-nonconforming gay men may suffer from discrimination not only from society at large, but from other gay men, who are most likely to have experienced stigmatization and may have been effeminate earlier in their lives. Drawing from anecdotes and findings from various sources, this article suggests that beyond many gay men's erotic preference for masculinity lies contempt and hostility toward effeminacy and effeminate men on sociopolitical and personal levels. Two correlates of gay men's anti-effeminacy attitudes are proposed: (a) hegemonic masculinity ideology, or the degree to which one subscribes to the value system in which masculinity is an asset, and men and masculinity are considered superior to women and femininity; and (b) masculinity consciousness, or the saliency of masculinity in one's self-monitoring, public self-consciousness, and self-concept. These two variables are hypothesized to interact with gay men's self-perceived masculinity-femininity and their history of defeminization in predicting attitudes toward effeminacy. Research is underway to measure levels of anti-effeminacy attitudes and explore hypothesized correlates.

  8. Community Cleavages: Gay and Bisexual Men’s Perceptions of Gay and Mainstream Community Acceptance in the Post-AIDS, Post-Rights Era

    Science.gov (United States)

    Lewis, Nathaniel M.; Bauer, Greta R.; Coleman, Todd A.; Blot, Soraya; Pugh, Daniel; Fraser, Meredith; Powell, Leanne

    2015-01-01

    Changes in gay and bisexual men’s connectedness to the gay community are related to the declining public visibility of HIV/AIDS and greater acceptance for homosexuality and bisexuality in mainstream society. Little work, however, has focused on perceived acceptance for subgroups within the gay community or broader society. Using interviews (n = 20) and a survey (n = 202) of gay and bisexual men in a mid-sized Canadian city, we find perceived hierarchies of acceptance for the various subgroups as well as an age effect wherein middle-aged men perceive the least acceptance for all groups. These differences are linked with the uneven impact of social, political, and institutional changes relevant to gay and bisexual men in Canada. PMID:26011048

  9. A new aluminium-hydrate species in hydrated Portland cements characterized by 27Al and 29Si MAS NMR spectroscopy

    International Nuclear Information System (INIS)

    Andersen, Morten Daugaard; Jakobsen, Hans J.; Skibsted, Jorgen

    2006-01-01

    Recent 27 Al MAS NMR studies of hydrated Portland cements and calcium-silicate-hydrate (C-S-H) phases have shown a resonance from Al in octahedral coordination, which cannot be assigned to the well-known aluminate species in hydrated Portland cements. This resonance, which exhibits the isotropic chemical shift δ iso = 5.0 ppm and the quadrupole product parameter P Q = 1.2 MHz, has been characterized in detail by 27 Al MAS and 27 Al{ 1 H} CP/MAS NMR for different hydrated white Portland cements and C-S-H phases. These experiments demonstrate that the resonance originates from an amorphous or disordered aluminate hydrate which contains Al(OH) 6 3- or O x Al(OH) 6-x (3+x)- units. The formation of the new aluminate hydrate is related to the formation of C-S-H at ambient temperatures, however, it decomposes by thermal treatment at temperatures of 70-90 o C. From the experiments in this work it is proposed that the new aluminate hydrate is either an amorphous/disordered aluminate hydroxide or a calcium aluminate hydrate, produced as a separate phase or as a nanostructured surface precipitate on the C-S-H phase. Finally, the possibilities of Al 3+ for Ca 2+ substitution in the principal layers and interlayers of the C-S-H structure are discussed

  10. Sexual and Intimacy Issues for Aging Gay Men

    Science.gov (United States)

    Pope, Mark; Wierzalis, Edward A.; Barret, Bob; Rankins, Michael

    2007-01-01

    The authors focus on the special issues involved in providing counseling to aging gay men regarding sex and intimacy. Although the stresses of aging experienced by gay men are similar to those of heterosexual men, older gay men face issues of a stigmatized sexual orientation, invisibility, negative stereotypes, and discrimination regarding aging.

  11. A Computationally Efficient Equation of State for Ternary Gas Hydrate Systems

    Science.gov (United States)

    White, M. D.

    2012-12-01

    The potential energy resource of natural gas hydrates held in geologic accumulations, using lower volumetric estimates, is sufficient to meet the world demand for natural gas for nearly eight decades, at current rates of increase. As with other unconventional energy resources, the challenge is to economically produce the natural gas fuel. The gas hydrate challenge is principally technical. Meeting that challenge will require innovation, but more importantly, scientific research to understand the resource and its characteristics in porous media. The thermodynamic complexity of gas hydrate systems makes numerical simulation a particularly attractive research tool for understanding production strategies and experimental observations. Simply stated, producing natural gas from gas hydrate deposits requires releasing CH4 from solid gas hydrate. The conventional way to release CH4 is to dissociate the hydrate by changing the pressure and temperature conditions to those where the hydrate is unstable. Alternatively, the guest-molecule exchange technology releases CH4 by replacing it with more thermodynamically stable molecules (e.g., CO2, N2). This technology has three advantageous: 1) it sequesters greenhouse gas, 2) it potentially releases energy via an exothermic reaction, and 3) it retains the hydraulic and mechanical stability of the hydrate reservoir. Numerical simulation of the production of gas hydrates from geologic deposits requires accounting for coupled processes: multifluid flow, mobile and immobile phase appearances and disappearances, heat transfer, and multicomponent thermodynamics. The ternary gas hydrate system comprises five components (i.e., H2O, CH4, CO2, N2, and salt) and the potential for six phases (i.e., aqueous, nonaqueous liquid, gas, hydrate, ice, and precipitated salt). The equation of state for ternary hydrate systems has three requirements: 1) phase occurrence, 2) phase composition, and 3) phase properties. Numerical simulations that predict

  12. A textual analysis of male gayness in Nakanjani Sibiya's novel ...

    African Journals Online (AJOL)

    ... represents gay images that are in agreement with the 1996 Constitution of South Africa, which protects the rights of gay people. The analysis of male gayness is situated within the theoretical framework of intercultural communication. Intercultural communication theory regards gay identities as microcultures or subcultures ...

  13. "Nothing Has Stopped Me. I Keep Going:" Black Gay Narratives

    Science.gov (United States)

    Bartone, Michael D.

    2017-01-01

    Are being Black and gay problematic in the United States? Are Black gay youth "suffering" with these two intersecting identities? Traditional Eurocentric epistemologies would have one believe that Black males, Black gay males, and gay males (liminal groups) are suffering, rarely acknowledging those successfully navigating through…

  14. Gas hydrate exploration activities in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Keun-Pil Park, K.P. [Korea Inst. of Geoscience and Mineral Resources, Gas Hydrate R and D Organization, Ministry of Knowledge Economy, Yuseong-gu, Daejeon (Korea, Republic of)

    2008-07-01

    Korea's first gas hydrate research project was launched in 1996 to study the gas hydrate potential in the Ulleung Basin of the East Sea. It involved a series of laboratory experiments followed by a preliminary offshore seismic survey and regional reconnaissance geophysical and marine geological surveys. The bottom simulating reflector (BSR) was interpreted to show wide area distribution in the southern part of the Ulleung Basin, and its average burial depth was 187 m below the sea floor in the East Sea. A three-phase 10-year National Gas Hydrate Development Program was launched in 2004 to estimate the potential reserves in the East Sea. It will involve drilling to identify natural gas hydrates and to determine the most optimized production methods. Drilling sites were proposed based on five indicators that imply gas hydrate occurrence, notably BSR, gas vent, enhanced seismic reflection, acoustic blanking and gas seeping structure. The UBGH-X-01 gas hydrate expedition in the East Sea Ulleung Basin involved 5 logging while drilling (LWD) surveys at three high priority sites. One wire line logging was implemented at the site of the UBGH09. A total 334 m of non-pressurized conventional cores and 16 pressure cores were obtained in late 2007. The UBGH-X-01 was successfully completed, recovering many natural samples of gas hydrate from 3 coring sites in the East Sea. 7 refs., 12 figs.

  15. Influence of Lithium Carbonate on C3A Hydration

    Directory of Open Access Journals (Sweden)

    Weiwei Han

    2018-01-01

    Full Text Available Lithium salts, known to ameliorate the effects of alkali-silica reaction, can make significant effects on cement setting. However, the mechanism of effects on cement hydration, especially the hydration of C3A which is critical for initial setting time of cement, is rarely reported. In this study, the development of pH value of pore solution, conductivity, thermodynamics, and mineralogical composition during hydration of C3A with or without Li2CO3 are investigated. The results demonstrate that Li2CO3 promotes C3A hydration through high alkalinity, due to higher activity of lithium ion than that of calcium ion in the solution and carbonation of C3A hydration products resulted from Li2CO3. Li2CO3 favors the C3A hydration in C3A-CaSO4·2H2O-Ca(OH2-H2O hydration system and affects the mineralogical variation of the ettringite phase(s.

  16. Balancing Accuracy and Computational Efficiency for Ternary Gas Hydrate Systems

    Science.gov (United States)

    White, M. D.

    2011-12-01

    Geologic accumulations of natural gas hydrates hold vast organic carbon reserves, which have the potential of meeting global energy needs for decades. Estimates of vast amounts of global natural gas hydrate deposits make them an attractive unconventional energy resource. As with other unconventional energy resources, the challenge is to economically produce the natural gas fuel. The gas hydrate challenge is principally technical. Meeting that challenge will require innovation, but more importantly, scientific research to understand the resource and its characteristics in porous media. Producing natural gas from gas hydrate deposits requires releasing CH4 from solid gas hydrate. The conventional way to release CH4 is to dissociate the hydrate by changing the pressure and temperature conditions to those where the hydrate is unstable. The guest-molecule exchange technology releases CH4 by replacing it with a more thermodynamically stable molecule (e.g., CO2, N2). This technology has three advantageous: 1) it sequesters greenhouse gas, 2) it releases energy via an exothermic reaction, and 3) it retains the hydraulic and mechanical stability of the hydrate reservoir. Numerical simulation of the production of gas hydrates from geologic deposits requires accounting for coupled processes: multifluid flow, mobile and immobile phase appearances and disappearances, heat transfer, and multicomponent thermodynamics. The ternary gas hydrate system comprises five components (i.e., H2O, CH4, CO2, N2, and salt) and the potential for six phases (i.e., aqueous, liquid CO2, gas, hydrate, ice, and precipitated salt). The equation of state for ternary hydrate systems has three requirements: 1) phase occurrence, 2) phase composition, and 3) phase properties. Numerical simulation of the production of geologic accumulations of gas hydrates have historically suffered from relatively slow execution times, compared with other multifluid, porous media systems, due to strong nonlinearities and

  17. Correlates of Gay-Related Name-Calling in Schools

    Science.gov (United States)

    Slaatten, Hilde; Hetland, Jørn; Anderssen, Norman

    2015-01-01

    The aim of this study was to examine whether attitudes about gay-related name-calling, social norms concerning gay-related name-calling among co-students, teacher intervention, and school-related support would predict whether secondary school pupils had called another pupil a gay-related name during the last month. A total of 921 ninth-grade…

  18. Major factors influencing the generation of natural gas hydrate in porous media

    Directory of Open Access Journals (Sweden)

    V.N. Khlebnikov

    2017-11-01

    Full Text Available Current researches related to natural gas hydrate mainly focus on its physical and chemical properties, as well as the approaches to the production (decomposition of hydrate. Physical modeling of the flow process in hydrate deposits is critical to the study on the exploitation or decomposition of hydrate. However, investigation of the dynamic hydrate process by virtue of porous media like sand-packed tubes which are widely used in petroleum production research is rarely reported in literature. In this paper, physical simulation of methane hydrate generation process was conducted using river sand-packed tubes in the core displacement apparatus. During the simulation, the influences of parameters such as reservoir temperature, methane pressure and reservoir model properties on the process of hydrate generation were investigated. The following results are revealed. First, the use of ice-melted water as the immobile water in the reservoir model can significantly enhance the rate of methane hydrate generation. Second, the process driving force in porous media (i.e., extents to which the experimental pressure or temperature deviating those corresponding to the hydrate phase equilibrium plays a key role in the generation of methane hydrate. Third, the induction period of methane hydrate generation almost does not change with temperature or pressure when the methane pressure is above 1.4 folds of the hydrate phase equilibrium pressure or the laboratory temperature is lower than the phase equilibrium temperature by 3 °C or more. Fourth, the parameters such as permeability, water saturation and wettability don't have much influence on the generation of methane hydrate.

  19. HYDRATE CORE DRILLING TESTS

    Energy Technology Data Exchange (ETDEWEB)

    John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

    2002-11-01

    The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate

  20. Courtesy stigma: the social implications of associating with a gay person.

    Science.gov (United States)

    Sigelman, C K; Howell, J L; Cornell, D P; Cutright, J D; Dewey, J C

    1991-02-01

    We investigated the operation of courtesy stigma with American male college students who reacted to a fictitious male student described as gay, rooming by choice with a gay male student, involuntarily assigned to room with a gay, or rooming with a male heterosexual. Among respondents who expressed strong intolerance of gays, the voluntary associate of a gay was perceived as having homosexual tendencies and as possessing the same stereotyped personality traits attributed to a gay. No such courtesy stigma was attached to the involuntary associate of a gay by these respondents. Relatively tolerant respondents engaged in no courtesy stigmatization at all. Thus, courtesy stigmatization occurred only under circumscribed conditions and appeared to depend more on the tendency of highly intolerant individuals to infer that a male student who apparently liked a gay individual was himself gay than on a motivation to maintain cognitive consistency.

  1. Hydration states of AFm cement phases

    Energy Technology Data Exchange (ETDEWEB)

    Baquerizo, Luis G., E-mail: luis.baquerizoibarra@holcim.com [Innovation, Holcim Technology Ltd., CH-5113 Holderbank (Switzerland); Matschei, Thomas [Innovation, Holcim Technology Ltd., CH-5113 Holderbank (Switzerland); Scrivener, Karen L. [Laboratory of Construction Materials, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Saeidpour, Mahsa; Wadsö, Lars [Building Materials, Lund University, Box 124, 221 000 Lund (Sweden)

    2015-07-15

    The AFm phase, one of the main products formed during the hydration of Portland and calcium aluminate cement based systems, belongs to the layered double hydrate (LDH) family having positively charged layers and water plus charge-balancing anions in the interlayer. It is known that these phases present different hydration states (i.e. varying water content) depending on the relative humidity (RH), temperature and anion type, which might be linked to volume changes (swelling and shrinkage). Unfortunately the stability conditions of these phases are insufficiently reported. This paper presents novel experimental results on the different hydration states of the most important AFm phases: monocarboaluminate, hemicarboaluminate, strätlingite, hydroxy-AFm and monosulfoaluminate, and the thermodynamic properties associated with changes in their water content during absorption/desorption. This data opens the possibility to model the response of cementitious systems during drying and wetting and to engineer systems more resistant to harsh external conditions.

  2. Observation of microstructure of hydrated Ca3SiO5

    International Nuclear Information System (INIS)

    Mori, Kazuhiro; Sato, Takashi; Fukunaga, Toshiharu; Oishi, Koji; Kimura, Katsuhiko; Iwase, Kenji; Sugiyama, Masaaki; Itoh, Keiji; Shikanai, Fumihito; Wuernisha, Tuerxun; Yonemura, Masao; Sulistyanintyas, Dyah; Tsukushi, Itaru; Takata, Shinich; Otomo, Toshiya; Kamiyma, Takashi; Kawai, Masayoshi

    2006-01-01

    Quasi-elastic neutron scattering experiments were carried out to evaluate the hydration rate of tricalcium silicate (Ca 3 SiO 5 ). Furthermore, in the early hydration period, a variation in surface roughness of Ca 3 SiO 5 was observed in nano-scale by the small-angle neutron scattering. From these results, it was found that the hydration rate of Ca 3 SiO 5 is suppressed when the surface of Ca 3 SiO 5 becomes rough through the creation of hydration products C-S-H gel and Ca(OH) 2 , and this roughness is associated with changes in the Ca 3 SiO 5 hydration rate

  3. Medical students' attitudes toward gay men.

    Science.gov (United States)

    Matharu, Kabir; Kravitz, Richard L; McMahon, Graham T; Wilson, Machelle D; Fitzgerald, Faith T

    2012-08-08

    Healthcare providers' attitudes toward sexual minorities influence patient comfort and outcomes. This study characterized medical student attitudes toward gay men, focusing on behavior, personhood, gay civil rights, and male toughness. A cross-sectional web-based anonymous survey was sent to medical students enrolled at the University of California, Davis (N = 371) with a response rate of 68%. Few respondents expressed negative attitudes toward gay men or would deny them civil rights. More negative responses were seen with respect to aspects of intimate behavior and homosexuality as a natural form of sexual expression. Men and students younger than 25 years old were more likely to endorse negative attitudes toward behavior as well as more traditional views on male toughness. We show that an important minority of students express discomfort with the behavior of gay men and hold to a narrow construction of male identity. These findings suggest that competency training must move beyond conceptual discussions and address attitudes toward behaviors through new pedagogical approaches.

  4. Geomechanical Performance of Hydrate-Bearing Sediment in Offshore Environments

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Holditch; Tad Patzek; Jonny Rutqvist; George Moridis; Richard Plumb

    2008-03-31

    The objective of this multi-year, multi-institutional research project was to develop the knowledge base and quantitative predictive capability for the description of geomechanical performance of hydrate-bearing sediments (hereafter referred to as HBS) in oceanic environments. The focus was on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. We have developed a robust numerical simulator of hydrate behavior in geologic media by coupling a reservoir model with a commercial geomechanical code. We also investigated the geomechanical behavior of oceanic HBS using pore-scale models (conceptual and mathematical) of fluid flow, stress analysis, and damage propagation. The objective of the UC Berkeley work was to develop a grain-scale model of hydrate-bearing sediments. Hydrate dissociation alters the strength of HBS. In particular, transformation of hydrate clusters into gas and liquid water weakens the skeleton and, simultaneously, reduces the effective stress by increasing the pore pressure. The large-scale objective of the study is evaluation of geomechanical stability of offshore oil and gas production infrastructure. At Lawrence Berkeley National Laboratory (LBNL), we have developed the numerical model TOUGH + Hydrate + FLAC3D to evaluate how the formation and disassociation of hydrates in seafloor sediments affects seafloor stability. Several technical papers were published using results from this model. LBNL also developed laboratory equipment and methods to produce realistic laboratory samples of sediments containing gas hydrates so that mechanical properties could be measured in the laboratory. These properties are required to run TOUGH + Hydrate + FLAC3D to evaluate seafloor stability issues. At Texas A&M University we performed a detailed literature review to determine what gas hydrate formation properties had been measured and reported in the literature. We

  5. The application of DTA and TG methods to investigate the non-crystalline hydration products of CaAl2O4 and Ca7ZrAl6O18 compounds

    International Nuclear Information System (INIS)

    Szczerba, Jacek; Madej, Dominika; Śnieżek, Edyta; Prorok, Ryszard

    2013-01-01

    Highlights: ► Hydrates, i.e. CAH 10 , C 2 AH 8 , C 3 AH 6 and C 4 AH 19 are formed during hydration of CaAl 2 O 4 and Ca 7 ZrAl 6 O 18 . ► Hydrated CaAl 2 O 4 and Ca 7 ZrAl 6 O 18 compounds were investigated by X-ray diffraction, SEM/EDS and thermal analysis. ► The hydration reaction proceeds as consumes the unreacted core of the CaAl 2 O 4 and Ca 7 ZrAl 6 O 18 grain. - Abstract: The hydration products and thermal decomposition mechanism of hydrated CaAl 2 O 4 and Ca 7 ZrAl 6 O 18 compounds were investigated by X-ray diffraction, SEM/EDS and thermal analysis. The processes of crystal hydrate nucleation and precipitation were preceded by the evolution of the X-ray amorphous phase during the first 24 h of hydration. DTA–TGA–EGA techniques allowed the study of the detailed decomposition and identification of intermediate and stable to be performed. The differential thermal analysis (DTA) curves of hydrated CaAl 2 O 4 and Ca 7 ZrAl 6 O 18 compounds show five similar endothermic peaks due to crystal water desorption. According to the quantitative TGA–EGA analyses performed on hydrated CaAl 2 O 4 and Ca 7 ZrAl 6 O 18 compounds, it was found that C 2 AH 8 , C 3 AH 6 and Al(OH) 3 phases are the main hydration products of CaAl 2 O 4 . Under the same laboratory conditions, the hydration of Ca 7 ZrAl 6 O 18 proceeds with the formation of mainly CAH 10 and AH 3 -gel phases. We provide the original illustrations of the hydrate crystals formation via amorphous phases

  6. Health Concerns for Gay and Lesbian Teens

    Science.gov (United States)

    ... Text Size Email Print Share Health Concerns for Gay and Lesbian Teens Page Content Article Body Sexual activity Most teens, whether they are gay, lesbian, bisexual , or straight, are not sexually active. ...

  7. Masculine Gender Role Conflict and Negative Feelings about Being Gay.

    Science.gov (United States)

    Sánchez, Francisco J; Westefeld, John S; Liu, William Ming; Vilain, Eric

    2010-04-01

    Professional psychologists who work with gay men have noted that traditional masculine ideals play a prominent role in the gay community whereby some endorse these traditional ideals and stigmatize effeminate behavior by other gay men. One hypothesis is that this behavior reflects negative feelings about being gay. This article examined this hypothesis by reporting the results of an online survey of 622 self-identified gay men. Participants completed the Gender Role Conflict Scale, Lesbian and Gay Identity Scale, the Social Desirability Scale, and questions related to the importance of masculinity. Results showed that most participants valued the public appearance of masculinity; and they ideally wished to be more masculine than they felt they were (Cohen's d = 0.42). A multiple regression analysis showed that the degree to which they valued masculinity and were concerned with violating masculine ideals was positively related with negative feelings about being gay (Cohen's f(2) = .67). These findings highlight the importance of exploring the role that masculine ideals play in gay client's lives given that negative feelings about oneself can adversely affect psychological well-being.

  8. Go home, gay boy! Or, why do Singaporean gay men prefer to "go home" and not "come out"?

    Science.gov (United States)

    Tan, Chris K K

    2011-01-01

    Anglo-American ontologies posit that gay men should come out to match their outer selves with their inner ones. In Confucianized Singapore, however, gay men refrain from coming out to their parents to avoid shaming their families. Instead, they couch their homosexuality in kinship terms and "go home" with their boyfriends (Chou, 2000). "Going home" gains familial acceptance, but it does not challenge mainstream discourses of homosexuality. By examining how Singaporean gay men negotiate their sexuality with their families, I question the validity of coming out and going home as both ontological discourses and strategies.

  9. Can hydrate dissolution experiments predict the fate of a natural hydrate system?

    Energy Technology Data Exchange (ETDEWEB)

    Hester, K.C.; Peltzer, E.T.; Dunk, R.M.; Walz, P.M.; Brewer, P.G. [Monterey Bay Aquarium Research Inst., Moss Landing, CA (United States); Dendy Sloan, E. [Colorado School of Mines, Golden, CO (United States). Center for Hydrate Research

    2008-07-01

    Gas hydrates are naturally occurring compounds found in permafrost regions and in oceans. In the natural environment, sufficient temperature and pressure conditions for hydrate formation exist over a significant portion of the ocean. However, in addition to pressure and temperature, the chemical potential of the gas in the hydrate must be equal to the surrounding waters. If the concentration of the gas in surrounding water is under-saturated with respect to the gas in the hydrate, the hydrate will dissolve to drive the system towards chemical equilibrium. This paper presented a dissolution study of exposed hydrate from outcrops at Barkley Canyon, located off Vancouver Island, British Columbia. A previous field experiment on synthetic methane hydrate samples had demonstrated that mass transfer controlled dissolution in under-saturated seawater. However, seafloor hydrate outcrops have been shown to have significant longevity compared to expected dissolution rates based upon convective boundary layer diffusion calculations. An in-situ dissolution experiment was performed on two distinct natural hydrate fabrics in order to help resolve this apparent disconnect between the dissolution rates of synthetic and natural hydrate. The paper presented a map of Barkley Canyon and discussed the field measurements and methods for the study. Exposed outcrops of gas hydrates were cored using a specially constructed stainless steel coring device and a hydraulic ram was located inside the corer. Hydrate samples were cored directly using the a manipulator arm and then injected into a sampling cell. The hydrate was then added to an open mesh exposure container, which allowed for exposure to ambient benthic currents with minimal disturbance. As well, in order to observe the slow dissolution of the hydrate in seawater at Barkley Canyon, time-lapse photography was employed. Last, the paper presented the results of the hydrate fabric porosities and hydrate dissolution rates. It was

  10. Permafrost-associated natural gas hydrate occurrences on the Alaska North Slope

    Science.gov (United States)

    Collett, T.S.; Lee, M.W.; Agena, W.F.; Miller, J.J.; Lewis, K.A.; Zyrianova, M.V.; Boswell, R.; Inks, T.L.

    2011-01-01

    In the 1960s Russian scientists made what was then a bold assertion that gas hydrates should occur in abundance in nature. Since this early start, the scientific foundation has been built for the realization that gas hydrates are a global phenomenon, occurring in permafrost regions of the arctic and in deep water portions of most continental margins worldwide. In 1995, the U.S. Geological Survey made the first systematic assessment of the in-place natural gas hydrate resources of the United States. That study suggested that the amount of gas in the gas hydrate accumulations of northern Alaska probably exceeds the volume of known conventional gas resources on the North Slope. Researchers have long speculated that gas hydrates could eventually become a producible energy resource, yet technical and economic hurdles have historically made gas hydrate development a distant goal. This view began to change in recent years with the realization that this unconventional resource could be developed with existing conventional oil and gas production technology. One of the most significant developments was the completion of the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well on the Alaska North Slope, which along with the Mallik project in Canada, have for the first time allowed the rational assessment of gas hydrate production technology and concepts. Almost 40 years of gas hydrate research in northern Alaska has confirmed the occurrence of at least two large gas hydrate accumulations on the North Slope. We have also seen in Alaska the first ever assessment of how much gas could be technically recovered from gas hydrates. However, significant technical concerns need to be further resolved in order to assess the ultimate impact of gas hydrate energy resource development in northern Alaska. ?? 2009 Elsevier Ltd.

  11. Problems of ecological and technical safety by exploration and production of natural gas hydrates

    Directory of Open Access Journals (Sweden)

    Chen-Chen

    2006-10-01

    Full Text Available Gas hydrates - the firm crystal connections form water (liquid water, ice, water vapor and low-molecular waterproof natural gases (mainly methane whose crystal structure effectively compresses gas e.s.: each cubic meter of hydrate can yield over 160 m3 of methane.In present time, the exploitation of the Messoyahsk (Russia and Mallik (Canada deposits of gas hydrates is conducted actively. The further perfection of prospecting methods in the field of studying gas hydrates containing sediments depends on the improvement of geophysical and the well test research, among which native-state core drilling is one of the major. Sampling a native-state core from gas hydrates sediments keeps not only the original composition but structural - textural features of their construction.Despite of the appeal to use gas hydrates as a perspective and ecologically pure fuel possessing huge resources, the investigation and development of their deposits can lead to a number of negative consequences connected with hazards arising from the maintenance of their technical and ecological safety of carrying out. Scales of the arising problems can change from local to regional and even global.

  12. Health Issues for Gay Men: Prevention First

    Science.gov (United States)

    ... Lifestyle Adult health Understand important health issues for gay men and men who have sex with men — ... Staff All men face certain health risks. However, gay men and men who have sex with men ...

  13. Understanding Gay Community Subcultures: Implications for HIV Prevention.

    Science.gov (United States)

    Prestage, Garrett; Brown, Graham; De Wit, John; Bavinton, Benjamin; Fairley, Christopher; Maycock, Bruce; Batrouney, Colin; Keen, Phillip; Down, Ian; Hammoud, Mohamed; Zablotska, Iryna

    2015-12-01

    Gay and bisexual men (GBM) who participate in gay community subcultures have different profiles, including differing risk behaviors. We examined men's participation in gay community subcultures, and its association with risk behavior. In a cross-sectional survey, 849 GBM provided information about men in their personal networks. We devised measures of their participation in five subcultural groupings and explored their associations with sexual behavior. We identified five subcultural groupings: sexually adventurous; bear tribes; alternative queer; party scene; and sexually conservative. Higher scores on the sexually adventurous measure was associated with being older, having more gay friends, being HIV-positive, and being more sexually active. It was also independently associated with unprotected anal intercourse with casual partners (AOR 1.82; 95 % CI 1.20-2.76; p = 0.005). HIV prevention strategies need to account for the different subcultural groupings in which GBM participate. Measures of engagement with gay subcultures are useful indicators of differential rates of risk behavior and modes of participation in gay community life. Men in more sexually adventurous subcultures are more likely to engage in sexual risk behavior.

  14. Gas hydrate nucleation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The overall aim of the project was to gain more knowledge about the kinetics of gas hydrate formation especially the early growth phase. Knowledge of kinetics of gas hydrate formation is important and measurements of gas hydrate particle size and concentration can contribute to improve this knowledge. An experimental setup for carrying out experimental studies of the nucleation and growth of gas hydrates has been constructed and tested. Multi wavelength extinction (MWE) was the experimental technique selected for obtaining particle diameter and concentration. The principle behind MWE is described as well as turbidity spectrum analysis that in an initial stage of the project was considered as an alternative experimental technique. Details of the experimental setup and its operation are outlined. The measuring cell consists of a 1 litre horizontal tube sustaining pressures up to 200 bar. Laser light for particle size determination can be applied through sapphire windows. A description of the various auxiliary equipment and of another gas hydrate cell used in the study are given. A computer program for simulation and analysis of gas hydrate experiments is based on the gas hydrate kinetics model proposed by Skovborg and Rasmussen (1993). Initial measurements showed that knowledge of the refractive index of gas hydrates was important in order to use MWE. An experimental determination of the refractive index of methane and natural gas hydrate is described. The test experiments performed with MWE on collectives of gas hydrate particles and experiments with ethane, methane and natural gas hydrate are discussed. Gas hydrate particles initially seem to grow mainly in size and at latter stages in number. (EG) EFP-94; 41 refs.

  15. Gas hydrate nucleation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    The overall aim of the project was to gain more knowledge about the kinetics of gas hydrate formation especially the early growth phase. Knowledge of kinetics of gas hydrate formation is important and measurements of gas hydrate particle size and concentration can contribute to improve this knowledge. An experimental setup for carrying out experimental studies of the nucleation and growth of gas hydrates has been constructed and tested. Multi wavelength extinction (MWE) was the experimental technique selected for obtaining particle diameter and concentration. The principle behind MWE is described as well as turbidity spectrum analysis that in an initial stage of the project was considered as an alternative experimental technique. Details of the experimental setup and its operation are outlined. The measuring cell consists of a 1 litre horizontal tube sustaining pressures up to 200 bar. Laser light for particle size determination can be applied through sapphire windows. A description of the various auxiliary equipment and of another gas hydrate cell used in the study are given. A computer program for simulation and analysis of gas hydrate experiments is based on the gas hydrate kinetics model proposed by Skovborg and Rasmussen (1993). Initial measurements showed that knowledge of the refractive index of gas hydrates was important in order to use MWE. An experimental determination of the refractive index of methane and natural gas hydrate is described. The test experiments performed with MWE on collectives of gas hydrate particles and experiments with ethane, methane and natural gas hydrate are discussed. Gas hydrate particles initially seem to grow mainly in size and at latter stages in number. (EG) EFP-94; 41 refs.

  16. Advanced Gas Hydrate Reservoir Modeling Using Rock Physics

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, Daniel

    2017-12-30

    Prospecting for high saturation gas hydrate deposits can be greatly aided with improved approaches to seismic interpretation and especially if sets of seismic attributes can be shown as diagnostic or direct hydrocarbon indicators for high saturation gas hydrates in sands that would be of most interest for gas hydrate production.

    A large 3D seismic data set in the deep water Eastern Gulf of Mexico was screened for gas hydrates using a set of techniques and seismic signatures that were developed and proven in the Central deepwater Gulf of Mexico in the DOE Gulf of Mexico Joint Industry Project JIP Leg II in 2009 and recently confirmed with coring in 2017.

    A large gas hydrate deposit is interpreted in the data where gas has migrated from one of the few deep seated faults plumbing the Jurassic hydrocarbon source into the gas hydrate stability zone. The gas hydrate deposit lies within a flat-lying within Pliocene Mississippi Fan channel that was deposited outboard in a deep abyssal environment. The uniform architecture of the channel aided the evaluation of a set of seismic attributes that relate to attenuation and thin-bed energy that could be diagnostic of gas hydrates. Frequency attributes derived from spectral decomposition also proved to be direct hydrocarbon indicators by pseudo-thickness that could be only be reconciled by substituting gas hydrate in the pore space. The study emphasizes that gas hydrate exploration and reservoir characterization benefits from a seismic thin bed approach.

  17. Gas hydrates

    Digital Repository Service at National Institute of Oceanography (India)

    Ramprasad, T.

    , not all of them are white like snow. Some hydrates from the deep Gulf of Mexico are richly colored in shades of yellow, orange, or even red. The ice-like masses are beautiful, and contrast with the dull gray of deep sea muds. Hydrates from the Blake... volcanoes and associated gas hydrates: Marine Geology, v. 167, p. 29-42. Milkov, A.V. and R. Sassen, 2001a, Estimate of gas hydrate resource, northwestern Gulf of Mexico continental slope: Marine Geology, v. 179, pp. 71-83. Milkov, A.V., Sassen, R...

  18. The "Marital" Liaisons of Gay Men.

    Science.gov (United States)

    Harry, Joseph

    1979-01-01

    Reports research on the nature of enduring sexual liaisons among homosexual men. Such relationships vary widely and may be subinstitutional adaptions to lack of community support. Gay men committed to the heterosexual world were less likely to enter enduring relationships. Open marriage is the more enduring form of gay male liaisons. (Author)

  19. Phase behavior of methane hydrate in silica sand

    International Nuclear Information System (INIS)

    Sun, Shi-Cai; Liu, Chang-Ling; Ye, Yu-Guang; Liu, Yu-Feng

    2014-01-01

    Highlights: • Hydrate p-T trace in coarse-grained sediment is consistent with that in bulk water. • Fine-grained sediment affects hydrate equilibrium for the depressed water activity. • Hydrate equilibrium in sediment is related to the pore size distribution. • The application of hydrate equilibrium in sediment depends on the actual condition. -- Abstract: Two kinds of silica sand powder with different particle size were used to investigate the phase behavior of methane hydrate bearing sediment. In coarse-grained silica sand, the measured temperature and pressure range was (281.1 to 284.2) K and (5.9 to 7.8) MPa, respectively. In fine-grained silica sand, the measured temperature and pressure range was (281.5 to 289.5) K and (7.3 to 16.0) MPa, respectively. The results show that the effect of coarse-grained silica sand on methane hydrate phase equilibrium can be ignored; however, the effect of fine-grained silica sand on methane hydrate phase equilibrium is significant, which is attributed to the depression of water activity caused by the hydrophilicity and negatively charged characteristic of silica particle as well as the pore capillary pressure. Besides, the analysis of experimental results using the Gibbs–Thomson equation shows that methane hydrate phase equilibrium is related to the pore size distribution of silica sand. Consequently, for the correct application of phase equilibrium data of hydrate bearing sediment, the geological condition and engineering requirement should be taken into consideration in gas production, resource evaluation, etc

  20. Shifting Focus: From Hydration for Performance to Hydration for Health.

    Science.gov (United States)

    Perrier, Erica T

    2017-01-01

    Over the past 10 years, literature on hydration biomarkers has evolved considerably - from (de)hydration assessment towards a more global definition of biomarkers of hydration in daily life. This shift in thinking about hydration markers was largely driven by investigating the differences that existed between otherwise healthy individuals whose habitual, ad-libitum drinking habits differ, and by identifying physiological changes in low-volume drinkers who subsequently increase their water intake. Aside from obvious differences in urinary volume and concentration, a growing body of evidence is emerging that links differences in fluid intake with small, but biologically significant, differences in vasopressin (copeptin), glomerular filtration rate, and markers of metabolic dysfunction or disease. Taken together, these pieces of the puzzle begin to form a picture of how much water intake should be considered adequate for health, and represent a shifting focus from hydration for performance, toward hydration for health outcomes. This narrative review outlines the key areas of research in which the global hydration process - including water intake, urinary hydration markers, and vasopressin - has been associated with health outcomes, focusing on kidney and metabolic endpoints. It will also provide a commentary on how various hydration biomarkers may be used in hydration for health assessment. Finally, if adequate water intake can play a role in maintaining health, how might we tell if we are drinking enough? Urine output is easily measured, and can take into account differences in daily physical activity, climate, dietary solute load, and other factors that influence daily water needs. Today, targets have been proposed for urine osmolality, specific gravity, and color that may be used by researchers, clinicians, and individuals as simple indicators of optimal hydration. However, there remain a large number of incomplete or unanswered research questions regarding the

  1. Masculine Gender Role Conflict and Negative Feelings about Being Gay

    Science.gov (United States)

    Sánchez, Francisco J.; Westefeld, John S.; Liu, William Ming; Vilain, Eric

    2009-01-01

    Professional psychologists who work with gay men have noted that traditional masculine ideals play a prominent role in the gay community whereby some endorse these traditional ideals and stigmatize effeminate behavior by other gay men. One hypothesis is that this behavior reflects negative feelings about being gay. This article examined this hypothesis by reporting the results of an online survey of 622 self-identified gay men. Participants completed the Gender Role Conflict Scale, Lesbian and Gay Identity Scale, the Social Desirability Scale, and questions related to the importance of masculinity. Results showed that most participants valued the public appearance of masculinity; and they ideally wished to be more masculine than they felt they were (Cohen’s d = 0.42). A multiple regression analysis showed that the degree to which they valued masculinity and were concerned with violating masculine ideals was positively related with negative feelings about being gay (Cohen’s f2 = .67). These findings highlight the importance of exploring the role that masculine ideals play in gay client’s lives given that negative feelings about oneself can adversely affect psychological well-being. PMID:20428323

  2. Explaining Couple Cohesion in Different Types of Gay Families

    Science.gov (United States)

    van Eeden-Moorefield, Brad; Pasley, Kay; Crosbie-Burnett, Margaret; King, Erin

    2012-01-01

    This Internet-based study used data from a convenience sample of 176 gay men in current partnerships to examine differences in outness, cohesion, and relationship quality between three types of gay male couples: first cohabiting partnerships, repartnerships, and gay stepfamilies. Also, we tested whether relationship quality mediated the link…

  3. A thermodynamic approach to the hydration of sulphate-resisting Portland cement

    International Nuclear Information System (INIS)

    Lothenbach, Barbara; Wieland, Erich

    2006-01-01

    A thermodynamic approach is used to model changes in the hydrate assemblage and the composition of the pore solution during the hydration of calcite-free and calcite-containing sulphate-resisting Portland cement CEM I 52.5 N HTS. Modelling is based on thermodynamic data for the hydration products and calculated hydration rates for the individual clinker phases, which are used as time-dependent input parameters. Model predictions compare well with the composition of the hydrate assemblage as observed by TGA and semi-quantitative XRD and with the experimentally determined compositions of the pore solutions. The calculations show that in the presence of small amounts of calcite typically associated with Portland cement, C-S-H, portlandite, ettringite and calcium monocarbonate are the main hydration products. In the absence of calcite in the cement, however, siliceous hydrogarnet instead of calcium monocarbonate is observed to precipitate. The use of a higher water-to-cement ratio for the preparation of a calcite-containing cement paste has a minor effect on the composition of the hydrate assemblage, while it significantly changes the composition of the pore solution. In particular, lower pH value and higher Ca concentrations appear that could potentially influence the solubility and uptake of heavy metals and anions by cementitious materials

  4. Hormones and silk. Gay men in the Spanish film comedies of the transition to democracy (1976-1981).

    Science.gov (United States)

    Melero, Alejandro

    2013-01-01

    This article studies the representation of gay men in Spanish comedies of the 1970s. It analyzes how cinema used the stereotypical image of gay men projected by the dictatorship and how, once it ended, this image endured in the comedy genre. It introduces film theories on the construction of humor taken from relevant authors, such as Jordan, Charney, Voitylla, and Petri. Afterward, it focuses on the works of Ozores as a filmmaker who encapsulates the main characteristics of the so-called comedia de mariquitas (sissy comedy). It analyzes how the construction of humor was based on the Francoist conception of gay men, and questions why the figure of the gay man was so effective in the production of comedy. Finally, this article refers to Dyer's theories around stereotyping, and develops them to study the Spanish context.

  5. Dehydration behaviour of hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Dette, S.S.; Stelzer, T.; Jones, M.J.; Ulrich, J. [Martin-Luther-Universitaet Halle-Wittenberg, Zentrum fuer Ingenieurwissenschaften, Verfahrenstechnik/TVT, 06099 Halle (Germany)

    2010-07-15

    Immersing a crystalline solvate in a suitable anti-solvent can induce phase transformation to solvent-free solid phase. In certain cases the solvent-mediated phase transition results in the generation of hollow, tubular structures. Both the tube dimensions of sodium-2-keto-L-gulonate anhydrate (skga) and the dehydration kinetics of sodium-2-keto-L-gulonate monohydrate (skgm) can be modified by the antisolvent employed. An explanation for the variable dehydration behaviour of skgm in the antisolvents is presented here. Furthermore, other crystalline hydrates were dehydrated in dry methanol. Providing an operational window can be found, any hydrate material could possibly find use in the production of tubes (micro- or nanotubes for different applications). The experimental conditions selected (dry methanol as antisolvent, dehydration temperature at 25 C) for the dehydration did not lead to the anhydrate tube growth for all hydrates investigated. Based upon the results presented here a first hypothesis is presented to explain this effect. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Medical students’ attitudes toward gay men

    Science.gov (United States)

    2012-01-01

    Background Healthcare providers’ attitudes toward sexual minorities influence patient comfort and outcomes. This study characterized medical student attitudes toward gay men, focusing on behavior, personhood, gay civil rights, and male toughness. Methods A cross-sectional web-based anonymous survey was sent to medical students enrolled at the University of California, Davis (N = 371) with a response rate of 68%. Results Few respondents expressed negative attitudes toward gay men or would deny them civil rights. More negative responses were seen with respect to aspects of intimate behavior and homosexuality as a natural form of sexual expression. Men and students younger than 25 years old were more likely to endorse negative attitudes toward behavior as well as more traditional views on male toughness. Conclusions We show that an important minority of students express discomfort with the behavior of gay men and hold to a narrow construction of male identity. These findings suggest that competency training must move beyond conceptual discussions and address attitudes toward behaviors through new pedagogical approaches. PMID:22873668

  7. Medical students’ attitudes toward gay men

    Directory of Open Access Journals (Sweden)

    Matharu Kabir

    2012-08-01

    Full Text Available Abstract Background Healthcare providers’ attitudes toward sexual minorities influence patient comfort and outcomes. This study characterized medical student attitudes toward gay men, focusing on behavior, personhood, gay civil rights, and male toughness. Methods A cross-sectional web-based anonymous survey was sent to medical students enrolled at the University of California, Davis (N = 371 with a response rate of 68%. Results Few respondents expressed negative attitudes toward gay men or would deny them civil rights. More negative responses were seen with respect to aspects of intimate behavior and homosexuality as a natural form of sexual expression. Men and students younger than 25 years old were more likely to endorse negative attitudes toward behavior as well as more traditional views on male toughness. Conclusions We show that an important minority of students express discomfort with the behavior of gay men and hold to a narrow construction of male identity. These findings suggest that competency training must move beyond conceptual discussions and address attitudes toward behaviors through new pedagogical approaches.

  8. Coming out narratives of older gay men living in New Zealand.

    Science.gov (United States)

    Neville, Stephen; Kushner, Bernie; Adams, Jeffery

    2015-10-01

    Explore the coming out narratives in a group of older gay men. A narrative gerontological approach was employed to explore the coming out narratives of older gay men. Semi-structured digitally recorded individual interviews were undertaken with 12 gay men aged between 65 and 81 years who lived in the community. Data were analysed using a narrative data analytic process. Three collective narratives related to the coming out of older gay men were identified: 'early gay experiences', 'trying not to be gay' and 'acceptance'. Older gay men come from diverse socio-cultural backgrounds. However, they all grew up in an era where same-sex attraction was a criminal offence. The path to accepting being a gay man was individualised and stressful for these participants. Consequently health and social service providers need to support the ongoing development of resilience and provide a person-centred approach to care that promotes wellbeing. © 2015 AJA Inc.

  9. Production of natural gas from methane hydrate by a constant downhole pressure well

    International Nuclear Information System (INIS)

    Ahmadi, Goodarz; Ji, Chuang; Smith, Duane H.

    2007-01-01

    Natural gas production from the dissociation of methane hydrate in a confined reservoir by a depressurizing downhole well was studied. The case that the well pressure was kept constant was treated, and two different linearization schemes in an axisymmetric configuration were used in the analysis. For different fixed well pressures and reservoir temperatures, approximate self similar solutions were obtained. Distributions of temperature, pressure and gas velocity field across the reservoir were evaluated. The distance of the decomposition front from the well and the natural gas production rate as functions of time were also computed. Time evolutions of the resulting profiles were presented in graphical forms, and their differences with the constant well output results were studied. It was shown that the gas production rate was a sensitive function of well pressure and reservoir temperature. The sensitivity of the results to the linearization scheme used was also studied

  10. Coping with Perceived Ethnic Prejudice on the Gay Scene

    Science.gov (United States)

    Jaspal, Rusi

    2017-01-01

    There has been only cursory research into the sociological and psychological aspects of ethnic/racial discrimination among ethnic minority gay and bisexual men, and none that focuses specifically upon British ethnic minority gay men. This article focuses on perceptions of intergroup relations on the gay scene among young British South Asian gay…

  11. Methane hydrates and the future of natural gas

    Science.gov (United States)

    Ruppel, Carolyn

    2011-01-01

    For decades, gas hydrates have been discussed as a potential resource, particularly for countries with limited access to conventional hydrocarbons or a strategic interest in establishing alternative, unconventional gas reserves. Methane has never been produced from gas hydrates at a commercial scale and, barring major changes in the economics of natural gas supply and demand, commercial production at a large scale is considered unlikely to commence within the next 15 years. Given the overall uncertainty still associated with gas hydrates as a potential resource, they have not been included in the EPPA model in MITEI’s Future of Natural Gas report. Still, gas hydrates remain a potentially large methane resource and must necessarily be included in any consideration of the natural gas supply beyond two decades from now.

  12. Heat Transfer Analysis of Methane Hydrate Sediment Dissociation in a Closed Reactor by a Thermal Method

    Directory of Open Access Journals (Sweden)

    Mingjun Yang

    2012-05-01

    Full Text Available The heat transfer analysis of hydrate-bearing sediment involved phase changes is one of the key requirements of gas hydrate exploitation techniques. In this paper, experiments were conducted to examine the heat transfer performance during hydrate formation and dissociation by a thermal method using a 5L volume reactor. This study simulated porous media by using glass beads of uniform size. Sixteen platinum resistance thermometers were placed in different position in the reactor to monitor the temperature differences of the hydrate in porous media. The influence of production temperature on the production time was also investigated. Experimental results show that there is a delay when hydrate decomposed in the radial direction and there are three stages in the dissociation period which is influenced by the rate of hydrate dissociation and the heat flow of the reactor. A significant temperature difference along the radial direction of the reactor was obtained when the hydrate dissociates and this phenomenon could be enhanced by raising the production temperature. In addition, hydrate dissociates homogeneously and the temperature difference is much smaller than the other conditions when the production temperature is around the 10 °C. With the increase of the production temperature, the maximum of ΔToi grows until the temperature reaches 40 °C. The period of ΔToi have a close relation with the total time of hydrate dissociation. Especially, the period of ΔToi with production temperature of 10 °C is twice as much as that at other temperatures. Under these experimental conditions, the heat is mainly transferred by conduction from the dissociated zone to the dissociating zone and the production temperature has little effect on the convection of the water in the porous media.

  13. Basics of development of gas hydrate deposits

    Energy Technology Data Exchange (ETDEWEB)

    Makogon, Yuri F.; Holditch, Stephen A.; Makogon, Taras Y.

    2005-07-01

    Natural gas hydrate deposits could possibly be an important energy resource during this century. However, many problems associated with producing these deposits must first be solved. The industry must develop new technologies to produce the gas, to forecast possible tectonic cataclysms in regions of gas hydrate accumulations, and to prevent damage to the environment. These global issues must be addressed by every company or country who wants to produce gas hydrate deposits. Cooperative research between industry and universities can lead to technology breakthroughs in coming years. This paper reviews the Messoyakha field and the Blake Ridge and Nankai areas to explain a methodology for estimating how much gas might be producible from gas hydrate deposits (GHDs) under various conditions. The Messoyakha field is located on land, while the Blake Ridge and Nankai areas are offshore. Messoyakha is the first and the only GHD where gas production from hydrates has reached commercial flow rates. The Blake Ridge GHD has been studied for 20 years and 11 wells have been drilled to collect gas-hydrate samples. The potential resources of gas (gas in place) from Blake Ridge is estimated at 37.7Oe10{sup 12} m{sup 3} (1.330 Tcf) in hydrate form and 19.3Oe10{sup 12}m{sup 3} (681 Bcf) [5] in free gas. To estimate how much of the potential resource can be produced we need a thorough understanding of both the geologic and the thermodynamic characteristics of the formations. (Author)

  14. Gay Youth in American Public High Schools: Invisible Diversity.

    Science.gov (United States)

    Reed, Donald B.

    Gay youth enter high school with the knowledge that they are different and with the belief that heterosexuality is normal and that homosexuality is not normal. Also, gay youth enter high school with the belief that honesty and integrity are important personal values. Additionally, the gay youth enter high school without family knowledge of their…

  15. Risk factors of methane hydrate resource development in the concentrated zones distributed in the eastern Nankai Trough

    Science.gov (United States)

    Yamamoto, K.; Nagakubo, S.

    2009-04-01

    Some environmental and safety concerns on the offshore methane hydrate development have been raised, but the ground of such allegations are sometime not fully reasonable. The risks of methane hydrate resource development to environment and safety should be discussed upon methane hydrate occurrences condition, the production methods, and the designs of production system, under comprehensively scientific manners. In the Phase 1 of the Methane Hydrate Exploitation Program in Japan (FY2001-2008), the Research Consortium for Methane Hydrate Resources in Japan (MH21 Research Consortium) found methane hydrate concentrated zones in the eastern Nankai Trough that are potential prospects for resource development. The concentrated zones are consisted of turbidite-derived sandy sediments and hydrate crystals in pore spaces of sand grains (pore-filling type structure). The MH21 Research Consortium proposed the depressurization method as prime technique due to its efficiency of gas production in such concentrated zones, and has tried to develop conceptual designs of production systems based on the information of existing devices and facilities. Under the condition and circumstances described above, the authors tried to extract and evaluate some risk factors concerning methane hydrate development using depressurization in the area. Leakage of methane gas, that is less harmful substance to ecosystem than heavier hydrocarbons, from production system can be one possible risk. However, in the case of gas production through wellbore, even if catastrophic damages happen in the subsea production system during gas production, the leakages do not continue because the borehole could be filled by seawater and depressurization is stopped immediately. Another possible risk is a leakage of produced gas through seafloor. If methane hydrate production makes high pressure or temperature zones in sediments, the risk should be considered. However, depressurization method makes opposite condition

  16. Sexual orientation and education politics: gay and lesbian representation in American schools.

    Science.gov (United States)

    Wald, Kenneth D; Rienzo, Barbara A; Button, James W

    2002-01-01

    In what has sometimes provoked a "culture war" over America's schools, gays and lesbians have sought an expanded voice in the making of education policy. This paper explores the factors that promote gay representation on school boards, how this variable in turn influences gay representation in both administrative and teaching positions, and how all three forms of gay representation relate to school board policies regarding sexual orientation education. Three of the four models drawn from the social movement literature help to explain gay school board representation. In a manner similar to other minority groups, gay representation on school boards directly or indirectly promotes the appointment of gays to administrative and teaching positions and the adoption of policies that address the problems faced by gay and lesbian students in the public schools.

  17. Impact of welan gum on tricalcium aluminate–gypsum hydration

    International Nuclear Information System (INIS)

    Ma Lei; Zhao Qinglin; Yao Chukang; Zhou Mingkai

    2012-01-01

    The retarding effect of welan gum on tricalcium aluminate–gypsum hydration, as a partial system of ordinary Portland cement (OPC) hydration, was investigated with several methods. The tricalcium aluminate–gypsum hydration behavior in the presence or absence of welan gum was researched by field emission gun scanning electron microscopy, X-ray diffraction and zeta potential analysis. Meanwhile, we studied the surface electrochemical properties and adsorption characteristics of welan gum by utilizing a zeta potential analyzer and UV–VIS absorption spectrophotometer. By adding welan gum, the morphology change of ettringite and retardation of hydration stages in tricalcium aluminate–gypsum system was observed. Moreover, we detected the adsorption behavior and zeta potential inversion of tricalcium aluminate and ettringite, as well as a rapid decrease in the zeta potential of tricalcium aluminate–gypsum system. The reduction on nucleation rate of ettringite and hydration activity of C 3 A was also demonstrated. Thus, through the adsorption effect, welan gum induces a retarding behavior in tricalcium aluminate–gypsum hydration. Highlights: ► Adsorption characteristics of welan gum on C 3 A and ettringite have been studied. ► C 3 A–gypsum hydration behavior and the hydration products are examined in L/S = 3. ► Welan gum retards the process of C 3 A–gypsum hydration. ► The addition of welan gum changes the nucleation growth of ettringite.

  18. #GoAllOut: A Physician's Reflection on Gay Games 9.

    Science.gov (United States)

    Ng, Henry H

    2015-03-01

    The article addresses the author's perspectives on the Gay Games on individual, community and public health. Using the Gay Games motto of "Participation, Inclusion, Personal Best," the author will explore the many benefits and effects of the Gay Games.

  19. A Gay Bibliography: Fifth Edition, Summer 1975.

    Science.gov (United States)

    American Library Association Social Responsibilities Round Table.

    This selective nonfiction bibliography features materials that present or support positive views of the gay experience, that help in understanding a gay-related issue, or that have special historical value. Listed are 200 nonfiction items: books, pamphlets, articles, periodicals, audiovisuals, directories,and other bibliographies. Complete…

  20. Planned gay father families in kinship arrangements

    NARCIS (Netherlands)

    Bos, H.H.M.W.

    2010-01-01

    The current study examined whether there are differences between gay father families (n = 36) and heterosexual families (n = 36) on father-child relationship, fathers' experiences of parental stress and children's wellbeing. The gay fathers in this study all became parents while in same-sex

  1. A Double-Blind, Randomised Study Comparing the Skin Hydration and Acceptability of Two Emollient Products in Atopic Eczema Patients with Dry Skin.

    Science.gov (United States)

    Djokic-Gallagher, Jasmina; Rosher, Phil; Oliveira, Gabriela; Walker, Jennine

    2017-09-01

    Healthcare professionals tend to recommend emollients based primarily on patient/consumer preference and cost, with cheaper options assumed to be therapeutically equivalent. The aim of this study was therefore to compare the effects on skin hydration of two emollients prescribed in the UK, Doublebase Dayleve™ gel (DELP) and a cheaper alternative, Zerobase Emollient™ cream (ZBC). This was a single-centre, randomised, double-blind, concurrent bi-lateral (within-patient) comparison in 18 females with atopic eczema and dry skin on their lower legs. DELP gel and ZBC cream were each applied to one lower leg twice daily for 4 days and on the morning only on day 5. The efficacy of both products was assessed by hydration measurements using a Corneometer CM825 probe (Courage-Khazaka Electronic). The measurements were made three times daily on days 1 to 5. The primary efficacy variable was the area under the curve (AUC) of the change from baseline corneometer readings over the 5 days. Skin hydration using DELP gel was significantly higher than using ZBC cream (p skin hydration observed for DELP gel was substantial and long lasting. In contrast, for ZBC cream, there was no significant improvement of the cumulative skin hydration as measured by the AUC (p = 0.22). DELP gel achieved substantial, long-lasting and cumulative skin hydration, whilst ZBC cream achieved no measurable improvement in skin hydration compared to before treatment. Healthcare professionals should be aware that different emollients can perform differently. Dermal Laboratories Ltd. EudraCT number:2014-001026-16.

  2. Sport fans' impressions of gay male athletes.

    Science.gov (United States)

    Campbell, Jamonn; Cothren, Denise; Rogers, Ross; Kistler, Lindsay; Osowski, Anne; Greenauer, Nathan; End, Christian

    2011-01-01

    The purpose of this study was to examine sport fans' impressions of gay male athletes. Participants formed impressions of a fictional athlete from their favorite team after reading a short scenario about the player. The scenarios described the athlete as being gay or straight, and either becoming a distraction or not causing a distraction to the team. While males' ratings of the athlete did not significantly differ, female fans formed significantly more positive impressions of the gay male player than the straight athlete. These results are discussed in terms of the ingroup bias and the shifting culture of homophobia in sport.

  3. Desafios dos Estudos Gays, Lésbicos e Transgêneros

    Directory of Open Access Journals (Sweden)

    Denilson Lopes

    2008-09-01

    Full Text Available Resumo: Este ensaio introduz algumas questões relativas aos estudos feministas, gays, lésbicos, transgênecos e teoria queer na busca de contribuições teórico-metodológicas na análise da cultura contemporânea. Palavras-chave: Estudos gays e lésbicos, estudos transgêneros, teoria queer, cultura. Abstrat: This essay introduces some issues related tofeminist studies, gay and lesbian studies, transgender studies and queer theory in the search of theoretical and methodological contributions in the analysis of contemporary culture. Key-words: Gay and Lesbian Studies, transgender studies, queer theory, culture

  4. Reported Effects of Masculine Ideals on Gay Men

    OpenAIRE

    Sánchez, Francisco J.; Greenberg, Stefanie T.; Liu, William Ming; Vilain, Eric

    2009-01-01

    This exploratory study used consensual qualitative research methodology (Hill et al., 2005) to analyze what gay men associate with masculinity and femininity, how they feel masculine ideals affect their self-image, and how masculine ideals affect their same-sex relationships. Written responses were collected from 547 self-identified gay men in the U.S. via an Internet-based survey. Findings supported previous reports that perceptions of gender roles among gay men appear based on masculine and...

  5. HIV among African American Gay and Bisexual Men

    Science.gov (United States)

    ... Syndicated Content Website Feedback HIV Among African American Gay and Bisexual Men Recommend on Facebook Tweet Share Compartir Black/African American a gay, bisexual, and other men who have sex with ...

  6. Delineation, Characterization and Assessment of Gas-hydrates: Examples from Indian Offshore

    Science.gov (United States)

    Sain, K.

    2017-12-01

    Successful test productions in McKenzie delta, Alaska, Nankai Trough and more recently in South China Sea have provided great hopes for production of gas-hydrates in near future, and boosted national programs of many countries including India. It has been imperative to map the prospective zones of gas-hydrates and evaluate their resource potential. Hence, we have adopted a systematic strategy for the delineation, characterization and quantification of gas-hydrates based on seismic traveltime tomography, full-waveform inversion, impedance inversion, attributes computation and rock-physical modeling. The bathymetry, seafloor temperature, total organic carbon content, sediment-thickness, rate of sedimentation, geothermal gradient imply that shallow sediments of Indian deep water are good hosts for occurrences of gas-hydrates. From the analysis of multi-channel seismic (MCS) data, we have identified the Krishna-Godavari (KG), Mahanadi and Andaman basins as prospective for gas-hydrates, and their presence has been validated by drilling and coring of Indian Expeditions-01 and -02. The MCS data also shows BSR-like features in the Cauvery, Kerala-Konkan and Saurashtra basins indicating that gas-hydrates cannot be ruled out from these basins also. We shall present several approaches that have been applied to field seismic and well-log data for the detection, characterization and quantification of gas-hydrates along the Indian margin.

  7. ‘The Ties that Bind Us’: The Hidden Knots of Gay Marriage

    Directory of Open Access Journals (Sweden)

    Bronwyn Winter

    2014-08-01

    Full Text Available Gay marriage has become a major transnational gay rights issue: a key marker of gay citizenship, to the extent that it is considered self-evident that its legalisation represents progress. Yet it is becoming apparent that this ‘progress’ is concurrent with other forms of exclusion. In this article, I argue that gay marriage is a convenient liberal smokescreen, leaving other exclusions unaddressed or even enabling their reinforcement. The discussion involves examination of three case studies: Argentina, the first Latin American country to legalise gay marriage in 2010; France, which legalised gay marriage in May, 2013; and Australia, which has not legalised gay marriage at the time of this writing.

  8. Effect of MXene (Nano-Ti3C2 on Early-Age Hydration of Cement Paste

    Directory of Open Access Journals (Sweden)

    Haibin Yin

    2015-01-01

    Full Text Available As a new two-dimensional material, MXene (nano-Ti3C2 has been widely applied in many fields, especially for reinforced composite materials. In this paper, mechanical testing, X-ray diffraction (XRD, hydration heat, scanning electron microscope (SEM, and EDS analysis were used to analyze the impact of MXene on cement hydration properties. The obtained results revealed that (a MXene could greatly improve the early compressive strength of cement paste with 0.04 wt% concentration, (b the phase type of early-age hydration products has not been changed after the addition of MXene, (c hydration exothermic rate within 72 h has small difference at different amount of MXene, and (d morphologies of hydration products were varied with the dosage of MXene, a lot of tufted ettringites appeared in 3 d hydration products when the content of MXene was 0.04 wt%, which will have a positive effect on improving the early mechanical properties of cement paste. MXene has inhibited the Portland cement hydration process; the main role of MXene in the cement hydration process is to promote the messy ettringite becoming regular distribution at a node and form network connection structure in the crystals growth process, making the mechanics performance of cement paste significantly improved.

  9. Gay- and Lesbian-Sounding Auditory Cues Elicit Stereotyping and Discrimination.

    Science.gov (United States)

    Fasoli, Fabio; Maass, Anne; Paladino, Maria Paola; Sulpizio, Simone

    2017-07-01

    The growing body of literature on the recognition of sexual orientation from voice ("auditory gaydar") is silent on the cognitive and social consequences of having a gay-/lesbian- versus heterosexual-sounding voice. We investigated this issue in four studies (overall N = 276), conducted in Italian language, in which heterosexual listeners were exposed to single-sentence voice samples of gay/lesbian and heterosexual speakers. In all four studies, listeners were found to make gender-typical inferences about traits and preferences of heterosexual speakers, but gender-atypical inferences about those of gay or lesbian speakers. Behavioral intention measures showed that listeners considered lesbian and gay speakers as less suitable for a leadership position, and male (but not female) listeners took distance from gay speakers. Together, this research demonstrates that having a gay/lesbian rather than heterosexual-sounding voice has tangible consequences for stereotyping and discrimination.

  10. Improving the Lives of Students, Gay and Straight Alike: Gay-Straight Alliances and the Role of School Psychologists

    Science.gov (United States)

    Murphy, Heather Elise

    2012-01-01

    Lesbian, gay, bisexual, and transgender (LGBT) students face many risk factors every day when they enter their school's door. These students often fear for their safety at school, are victimized, have academic difficulties, suffer from issues with their identity development, and are at risk for suicide. School-based Gay-Straight Alliances (GSAs)…

  11. A prediction method of natural gas hydrate formation in deepwater gas well and its application

    Directory of Open Access Journals (Sweden)

    Yanli Guo

    2016-09-01

    Full Text Available To prevent the deposition of natural gas hydrate in deepwater gas well, the hydrate formation area in wellbore must be predicted. Herein, by comparing four prediction methods of temperature in pipe with field data and comparing five prediction methods of hydrate formation with experiment data, a method based on OLGA & PVTsim for predicting the hydrate formation area in wellbore was proposed. Meanwhile, The hydrate formation under the conditions of steady production, throttling and shut-in was predicted by using this method based on a well data in the South China Sea. The results indicate that the hydrate formation area decreases with the increase of gas production, inhibitor concentrations and the thickness of insulation materials and increases with the increase of thermal conductivity of insulation materials and shutdown time. Throttling effect causes a plunge in temperature and pressure in wellbore, thus leading to an increase of hydrate formation area.

  12. Exploring talk about sexuality and living gay social lives among Chinese and South Asian gay and bisexual men in Auckland, New Zealand.

    Science.gov (United States)

    Adams, Jeffery; Neville, Stephen

    2018-02-15

    To identify ways Chinese and South Asian gay and bisexual men living in Auckland talk about issues related to sexuality and experiences of living 'gay social lives.' Results will be available to inform health policy and practice. A qualitative design with individual interviews and thematic analysis was used. Semi-structured digitally recorded interviews were undertaken with 27 Chinese and 17 South Asian gay and bisexual men living in Auckland. Four themes in the data related to talk about sexuality and living gay social lives are reported: (a) 'Happy in my skin': Being gay is Ok! (b) 'To come out or not': Managing sexual identity, (c) 'Places to go, people to see': Connecting with others, and (d) 'What's wrong with being Asian': Tolerating discrimination. There are many similarities in the ways these men talked about their identity and sexuality that can be usefully considered by health policy makers and service planners. The concept of gay (and bisexual) sexuality had some salience for the men interviewed, despite the adoption and acknowledgement of same-sex identity being a relatively new phenomenon in some Asian countries. This supports the use of these terms in local health interventions. However, as these men closely managed their gay identity and typically had not disclosed their sexuality to others, including healthcare professionals, interventions to address the skills and comfort of healthcare providers in addressing sexuality in clinical settings appear warranted to facilitate optimal healthcare. These men are not well connected with others and this has implications for HIV health promotion that is based on creating cultural norms among networks to encourage safe sex. Discrimination results in many Chinese and South Asian gay and bisexual men disengaging from connecting with others and should be addressed.

  13. Age cohort differences in the developmental milestones of gay men.

    Science.gov (United States)

    Drasin, Harry; Beals, Kristin P; Elliott, Marc N; Lever, Janet; Klein, David J; Schuster, Mark A

    2008-01-01

    As the social context in which gay men live changes due to greater visibility, greater acceptance, and easier access to gay subculture, gay males may self-identify and take part in gay social activities at earlier ages than in the past. This study examined whether developmental milestones associated with sexual orientation for gay men have changed over the past several decades. A large and diverse sample of 2,402 gay men who responded to a 1994 survey published in a national magazine provided retrospective information on the age at which they reached individual psychological, social, and sexual behavior developmental milestones. We found evidence that individual psychological and sexual behavior milestones (e.g., awareness of attraction to males, having an orgasm with other male) are slowly moving toward earlier chronological ages (by 1 year of age every 8-25 years, p coming out) are moving more rapidly in a similar direction (by 1 year of age every 2-5 years, p < 0.001). The authors perform an innovative sensitivity test to demonstrate the persistence of the finding after correcting for the bias attributable to underrepresentation of those who have not yet self-identified as gay in such samples.

  14. The appearance potency of gay and straight men’s websites

    OpenAIRE

    Jankowski, G.; Slater, A.; Tiggemann, M.; Fawkner, H.

    2016-01-01

    Gay men's greater body dissatisfaction compared to straight men has been explained as a result of gay men’s more 'appearance potent' subculture. This study aimed to critically appraise this explanation by assessing images of men and women for their physical characteristics and objectification across 8 popular gay and straight men's dating and porn websites. 1,415 images of men and 715 images of women across the website’s main pages were coded. Results showed that the gay men's websites featur...

  15. [Study on the causes of sexual orientation of gay].

    Science.gov (United States)

    Zhang, Yan-hui; Bao, Yu-gang; Chen, Hao; Tan, Hong-zhuan

    2013-11-01

    To explore the relevant factors of the causes of sexual orientations of gay. From March to June 2013, 350 gays were recruited from one music bar and three bath centers where gays frequently visited in Changsha city, by proportional stratified sampling method. Meanwhile, another 332 males who identify themselves as non-homosexuality were also recruited considering the composition of ages, gender and educational background. Questionnaire survey was conducted to all the subjects, with 300 effective ones reclaimed. The questionnaire included the general demographic information, traits of character, the condition of foster in childhood and information of family members. The differences between the gays and non-homosexuality groups were analyzed to explore the causes of the sexual orientations of gays. There were statistical significant differences between gays and non- homosexuality group on following indexes (χ(2) was 59.63, 5.90, 16.01, 84.99, 161.57, 77.77, 112.32, 190.84, 30.10 respectively, all of P books or films about homosexual and experienced sexual pleasure from that before the age of 18. The rate of gays on these indexes was separately 62.3% (187/300), 57.7% (173/300) , 62.3% (187/300) , 63.0% (189/300), 67.3% (202/300) , 62.7% (189/300), 68.0% (204/300), 65.0% (195/300) and the rate on these indexes of non-homosexuality group was separately 21.3% (64/300), 28.0% (84/300) , 25.0% (75/300) , 12.7% (38/300), 31.3% (94/300), 17.7% (53/300) , 12.7% (38/300), 42.7% (128/300) . The rate of gays on these factors:the youngest boy in family, had the father or twin brothers who were homosexual or self identified as gay was 62.7% (188/300), 56.0% (168/300) and 62.0% (18/29) respectively; and the rate was 40.7% (122/300), 4.0% (12/300) and 20.0% (2/10), respectively among non-homosexuality group. The difference showed statistical significance (χ(2) was 34.52, 193.14, 5.27 respectively, all of P gays maybe was family relationship, tend and education since childhood

  16. Portuguese Older Gay Men: Pathways to Family Integrity

    Directory of Open Access Journals (Sweden)

    Filipa Daniela Marques

    2016-08-01

    Full Text Available Abstract Research in the field of older gay men remains scarce. This exploratory study examines older gay men's experiences in the construction of family integrity (versus disconnection and alienation. The family integrity approach is a developmental perspective that links ego integrity to a larger process of constructing meaning within the family system. The sample comprises ten participants (from 60 to 88 years old. A semi-structured interview was conducted and submitted to content analysis. The main findings suggest three experiences in older gay men's construction of family integrity: (i influence of homosexuality throughout life; (ii establishing a family of choice; (iii creating a legacy associated with homosexuality. Family integrity in older gay men seems to evolve from disclosure at a young age to making homosexuality a legacy in old age.

  17. Permeability of sediment cores from methane hydrate deposit in the Eastern Nankai Trough, Japan

    Science.gov (United States)

    Konno, Y.; Yoneda, J.; Egawa, K.; Ito, T.; Jin, Y.; Kida, M.; Suzuki, K.; Nakatsuka, Y.; Nagao, J.

    2013-12-01

    Effective and absolute permeability are key parameters for gas production from methane-hydrate-bearing sandy sediments. Effective and/or absolute permeability have been measured using methane-hydrate-bearing sandy cores and clayey and silty cores recovered from Daini Atsumi Knoll in the Eastern Nankai Trough during the 2012 JOGMEC/JAPEX Pressure coring operation. Liquid-nitrogen-immersed cores were prepared by rapid depressurization of pressure cores recovered by a pressure coring system referred to as the Hybrid PCS. Cores were shaped cylindrically on a lathe with spraying of liquid nitrogen to prevent hydrate dissociation. Permeability was measured by a flooding test or a pressure relaxation method under near in-situ pressure and temperature conditions. Measured effective permeability of hydrate-bearing sediments is less than tens of md, which are order of magnitude less than absolute permeability. Absolute permeability of clayey cores is approximately tens of μd, which would perform a sealing function as cap rocks. Permeability reduction due to a swelling effect was observed for a silty core during flooding test of pure water mimicking hydrate-dissociation-water. Swelling effect may cause production formation damage especially at a later stage of gas production from methane hydrate deposits. This study was financially supported by the Research Consortium for Methane Hydrate Resources in Japan (MH21 Research Consortium) that carries out Japan's Methane Hydrate R&D Program conducted by the Ministry of Economy, Trade and Industry (METI).

  18. Hysteresis of methane hydrate formation/decomposition at subsea geological conditions

    International Nuclear Information System (INIS)

    Klapproth, Alice; Piltz, Ross; Peterson, Vanessa K.; Kennedy, Shane J.; Kozielski, Karen A.; Hartley, Patrick G.

    2009-01-01

    Full text: Gas hydrates are a major risk when transporting oil and gas in offshore subsea pipelines. Under typical conditions in these pipelines (at high pressure and low temperature) the formation of gas hydrates is favourable. The hydrates form large solid plugs that can block pipelines and can even cause them to burst. This represents a major problem for the gas mining industry, which currently goes to extreme measures to reduce the risk of hydrate formation because there is no reliable experimental data on hydrate processes. The mechanisms of gas hydrate formation, growth and inhibition are poorly understood. A clear understanding of the fundamental processes will allow development of cost effective technologies to avoid production losses in gas pipelines. We are studying the nucleation of the methane hydrates by measuring the hysteresis of hydrate formation/decomposition by neutron diffraction. When a gas hydrate is decomposed (melted) the resulting water has a 'supposed memory effect' raising the probability of rapid hydrate reformation. This rapid reformation does not occur for pure water where nucleation can be delayed by several hours (induction time) due to metastability [1]. The memory effect can only be destroyed by extreme heating of the effected area. Possible causes of this effect include residual water structure, persistent hydrate crystal lites remaining in solution and remaining dissolved gas. We will compare the kinetics of formation and the stability region of hydrate formation of 'memory' water for comparison with pure water. This information has important implications for the oil and gas industry because it should provide a better understanding of the role of multiple dissociation and reformation of gas hydrates in plug formation.

  19. Men as victims: "victim" identities, gay identities, and masculinities.

    Science.gov (United States)

    Dunn, Peter

    2012-11-01

    The impact and meanings of homophobic violence on gay men's identities are explored with a particular focus on their identities as men and as gay men. Homosexuality can pose a challenge to conventional masculinities, and for some gay men, being victimized on account of sexual orientation reawakens conflicts about their masculinity that they thought they had resolved. Being victimized can reinvoke shame that is rooted in failure or unwillingness to uphold masculine norms. For some gay men, victimization therefore has connotations of nonmasculinity that make being a victim an undesirable status, yet that status must be claimed to obtain a response from criminal justice or victim services. Men who experience homophobic abuse are helped by accepting a victim identity, but only if they can quickly move on from it by reconstructing a masculine gay (nonvictim) identity. This process can be facilitated by agencies such as the police and victim services, provided they help men exercise agency in "fighting back," that is, resisting further victimization and recovering.

  20. Les commerces gays et le processus de gentrification

    Directory of Open Access Journals (Sweden)

    Colin Giraud

    2009-04-01

    Full Text Available Interrogeant le rôle des populations homosexuelles dans la gentrification d’un ancien quartier historique de Paris (celui du Marais, cet article aborde cette question dans sa dimension commerciale. Depuis le début des années 80, l’implantation de commerces gays dans ce secteur a accompagné les effets de la gentrification et les a même accélérés pour partie depuis les années 90. Aujourd’hui cependant, la relation entre cette présence commerciale spécifique et les transformations socio-économiques de ce quartier parisien apparaissent nettement plus ambigus.In this paper, we examinate the role of gay men towards gentrification and urban renaissance by focusing on gay business development in “Le Marais”. We demonstrate that, in this old neighbourhood of the city-center, the emergence of a gay commercial area has supported gentrification during the eighties and then contributed to the urban, economical and cultural renaissance. The historical link between gentrification and “gay spaces” has changed and became since a few years more and more diversified.

  1. Gay men's experiences of surrogacy clinics in India.

    Science.gov (United States)

    Riggs, Damien W; Due, Clemence; Power, Jennifer

    2015-01-01

    While growing numbers of Australian gay men are entering into 'offshore' surrogacy arrangements in order to become parents, little empirical research has been conducted with this population. This article reports on a qualitative analysis of interviews with 12 gay men who had entered into surrogacy arrangements in India. The findings outline both positive and negative experiences in terms of support pre-conception, during the birth and post-birth. Changes to legislation in India mean that gay men can no longer access surrogacy services there, but it is important to understand the experiences of men who had previously accessed those services. The article concludes by highlighting aspects of the data that demonstrate the particular experiences of gay men who undertake offshore surrogacy arrangements, especially with regard to their need for support and involvement in all aspects of the process. A more thoroughly developed network of care may help to facilitate such support and this may further increase the positive outcomes reported by gay men who form families through surrogacy arrangements. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  2. Hydration mechanism and leaching behavior of bauxite-calcination-method red mud-coal gangue based cementitious materials

    International Nuclear Information System (INIS)

    Zhang, Na; Li, Hongxu; Liu, Xiaoming

    2016-01-01

    Highlights: • Nanocrystalline regions in size of ∼5 nm were found in the amorphous C-A-S-H gel. • A hydration model was proposed to clarify the hydration mechanism. • The developed cementitious materials are environmentally acceptable. - Abstract: A deep investigation on the hydration mechanism of bauxite-calcination-method red mud-coal gangue based cementitious materials was conducted from viewpoints of hydration products and hydration heat analysis. As a main hydration product, the microstructure of C-A-S-H gel was observed using high resolution transmission electron microscopy. It was found that the C-A-S-H gel is composed of amorphous regions and nanocrystalline regions. Most of regions in the C-A-S-H gel are amorphous with continuous distribution, and the nanocrystalline regions on scale of ∼5 nm are dispersed irregularly within the amorphous regions. The hydration heat of red mud-coal gangue based cementitious materials is much lower than that of the ordinary Portland cement. A hydration model was proposed for this kind of cementitious materials, and the hydration process mainly consists of four stages which are dissolution of materials, formation of C-A-S-H gels and ettringite, cementation of hydration products, and polycondensation of C-A-S-H gels. There are no strict boundaries among these four basic stages, and they proceed crossing each other. Moreover, the leaching toxicity tests were also performed to prove that the developed red mud-coal gangue based cementitious materials are environmentally acceptable.

  3. Hydration mechanism and leaching behavior of bauxite-calcination-method red mud-coal gangue based cementitious materials

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Na; Li, Hongxu [School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Beijing Key Laboratory of Rare and Precious Metals Green Recycling and Extraction, University of Science and Technology Beijing, Beijing 100083 (China); Liu, Xiaoming, E-mail: liuxm@ustb.edu.cn [School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Beijing Key Laboratory of Rare and Precious Metals Green Recycling and Extraction, University of Science and Technology Beijing, Beijing 100083 (China)

    2016-08-15

    Highlights: • Nanocrystalline regions in size of ∼5 nm were found in the amorphous C-A-S-H gel. • A hydration model was proposed to clarify the hydration mechanism. • The developed cementitious materials are environmentally acceptable. - Abstract: A deep investigation on the hydration mechanism of bauxite-calcination-method red mud-coal gangue based cementitious materials was conducted from viewpoints of hydration products and hydration heat analysis. As a main hydration product, the microstructure of C-A-S-H gel was observed using high resolution transmission electron microscopy. It was found that the C-A-S-H gel is composed of amorphous regions and nanocrystalline regions. Most of regions in the C-A-S-H gel are amorphous with continuous distribution, and the nanocrystalline regions on scale of ∼5 nm are dispersed irregularly within the amorphous regions. The hydration heat of red mud-coal gangue based cementitious materials is much lower than that of the ordinary Portland cement. A hydration model was proposed for this kind of cementitious materials, and the hydration process mainly consists of four stages which are dissolution of materials, formation of C-A-S-H gels and ettringite, cementation of hydration products, and polycondensation of C-A-S-H gels. There are no strict boundaries among these four basic stages, and they proceed crossing each other. Moreover, the leaching toxicity tests were also performed to prove that the developed red mud-coal gangue based cementitious materials are environmentally acceptable.

  4. Structure changes in the sol-gel systems of hydrated oxides

    International Nuclear Information System (INIS)

    Gaponov, Y.A.; Karakchiev, L.G.; Lyakhov, N.Z.; Tolochko, B.P.; Ito, K.; Amemiya, Y.

    1998-01-01

    Sols of hydrated aluminium oxide, hydrated zirconium oxide and their mixtures were investigated during the xerogel-amorphous-product-crystalline-product transition by SAXS using synchrotron radiation. In the different temperature regions certain changes in structure and morphology were observed. Some correlation between the characteristics of the initial sols and their mixtures (the size and shape of the pores) was observed. In the temperature region 298-1173 K the characteristics of the mixed sol are defined by the characteristics of the initial sols

  5. Modeling the hydration process of bean grains coated with carnauba wax

    Directory of Open Access Journals (Sweden)

    Aline Almeida da Paixão

    2017-08-01

    Full Text Available Edible waxes are widely used to maintain foodstuff until they are consumed. However, some products may be subjected to industrial procedures, such as hydration, prior to their consumption. Hydration of a material is a complex process, which aims to reconstitute the original characteristics of a product when in contact with a liquid phase. An important agricultural product that requires this procedure is beans. Thus, the purpose of this work is to study the hydration process of beans (cultivar BRSMG Majestoso in different temperatures and concentrations of carnauba wax, which is applied on the product surface. Beans with initial moisture content of 0.2015, 0.1972 and 0.1745 (d.b. corresponding to treatments 0 (witness, 1 (wax diluted in water in the ratio 1:1, and 2 (carnauba wax, without dilution were used. Later, these samples were imbibed in distilled water at temperatures of 20, 30 and 40 ºC, for 15 h. The temperature and the carnauba wax influenced the water absorption rate. The Peleg model described satisfactory experimental data and the Mitscherlich model presented biased residual distribution. The constants C1 and C2 of the Peleg model exhibited opposite behaviors with increasing temperatures in the hydration process.

  6. Report on the research and development achievements in fiscal 1999 on the international research cooperation project for comprehensive development and utilization technologies for gas hydrate resources; 1999 nendo gas hydrate shigen no energy sogo kaihatsu riyo gijutsu no kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This paper reports the achievements in fiscal 1999 on development of gas hydrate resources. As a result of synthesizing gas hydrates in deposit systems, identifying stability zones in compositions, and studying thermal conductivity and dielectric constant of the deposits, the estimation accuracy has been enhanced steadily in estimating hydrate existing areas in actual frost areas. In the collecting technologies, a proposal was presented for a system by which carbon dioxide is introduced into ground beds at the same time as recovering gases, and gas hydrates are displaced with carbon dioxide hydrates. The displacement phenomenon was verified experimentally by controlling temperatures and pressures. Even below the freezing point, the production rate of the carbon dioxide hydrates is fast if it is above minus 4 degrees C. Salt diffusion behavior important in control of the production and decomposition, and action mechanisms of production and suppression agents were made clear microscopically. Experimental and theoretical discussions were given on dynamics of the production and decomposition. The cage occupation rate of methane hydrates was quantitatively measured successfully by using the Raman spectroscopy. Hydrates of gas mixture were utilized to have verified the possibility of separating the gas mixture constituents. (NEDO)

  7. Method of purifying uranium tetrafluoride hydrate and preparing uranium (VI) peroxide hydrate using a fluoride complexing agent

    International Nuclear Information System (INIS)

    Barreiro, A.J.; Lowe, C.M.T.; Lefever, J.A.; Pyman, R.L.

    1983-01-01

    The annual production of phosphate rock, on the order of about 30-40 million tons yearly, represents several million pounds of uranium. The present invention provides a process of purifying uranium tetrafluoride hydrate to produce a uranium (VI) peroxide product meeting 'yellow cake' standards using a double precipitation procedure. A fluoride complexing agent is used in the precipitation

  8. Stereotypes of Older Lesbians and Gay Men

    Science.gov (United States)

    Wright, Sara L.; Canetto, Silvia Sara

    2009-01-01

    This study examined stereotypes of older lesbians and gay men. Key findings are that older lesbians and gay men were perceived as similar to older heterosexual women and men with regard to aging stereotypes, such as being judicious. At the same time, sexual minorities were targets of unique stereotypes. Consistent with the implicit inversion…

  9. Gas hydrates in the Ulleung Basin, East Sea of Korea

    Directory of Open Access Journals (Sweden)

    Byong-Jae Ryu Michael Riedel

    2017-01-01

    Full Text Available To develop gas hydrates as a potential energy source, geophysical surveys and geological studies of gas hydrates in the Ulleung Basin, East Sea off the east coast of Korea have been carried out since 1997. Bottom-simulating reflector (BSR, initially used indicator for the potential presence of gas hydrates was first identified on seismic data acquired in 1998. Based on the early results of preliminary R&D project, 12367 km of 2D multichannel reflection seismic lines, 38 piston cores, and multi-beam echo-sounder data were collected from 2000 to 2004. The cores showed high amounts of total organic carbon and high residual hydrocarbon gas levels. Gas composition and isotope ratios define it as of primarily biogenic origin. In addition to the BSRs that are widespread across the basin, numerous chimney structures were found in seismic data. These features indicate a high potential of the Ulleung Basin to host significant amounts of gas hydrate. Dedicated geophysical surveys, geological and experimental studies were carried out culminating in two deep drilling expeditions, completed in 2007 and 2010. Sediment coring (including pressure coring, and a comprehensive well log program complements the regional studies and were used for a resource assessment. Two targets for a future test-production are currently proposed: pore-filling gas hydrate in sand-dominated sediments and massive occurrences of gas hydrate within chimney-like structures. An environmental impact study has been launched to evaluate any potential risks to production.

  10. Body image in gay and straight men: a qualitative study.

    Science.gov (United States)

    Morgan, John F; Arcelus, Jon

    2009-11-01

    Recent research has emphasized vulnerability to eating disorders in gay men, with calls for research on causality, cultural factors and focus on a younger age cohort. This study aimed to examine body image and related eating behaviours in younger gay and straight men. Qualitative study using a sample of gay and straight male university students, applying audiotaped and transcribed depth interview subjected to interpretative phenomenological analysis. Fifteen young men (18-24) with a spectrum of sexual orientation (gay, straight and bisexual) agreed to participate. Five dominant categories emerged: body image ideal, external influences, perception of body image, dieting, mechanisms for modification (diet, exercise, cosmetics) and sexual orientation. Health and aesthetic ideals appear less divorced for young men than women, offering some degree of protection from eating disorders. Nonetheless there is widespread body dissatisfaction. Media and social influences are powerful, particularly for single gay men, but the study suggests fewer differences than similarities between gay and straight men. Copyright (c) 2009 John Wiley & Sons, Ltd and Eating Disorders Association.

  11. Gas-hydrate-bearing sand reservoir systems in the offshore of India: Results of the India National Gas Hydrate Program Expedition 02

    Science.gov (United States)

    Kumar, P.; Collett, Timothy S.; Vishwanath, K.; Shukla, K.M.; Nagalingam, J.; Lall, M.V.; Yamada, Y; Schultheiss, P.; Holland, M.

    2016-01-01

    The India National Gas Hydrate Program Expedition 02 (NGHP-02) was conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India using the deepwater drilling vessel Chikyu. The primary goal of this expedition was to explore for highly saturated gas hydrate occurrences in sand reservoirs that would become targets for future production tests. The first two months of the expedition were dedicated to logging-whiledrilling (LWD) operations, with a total of 25 holes drilled and logged. The next three months were dedicated to coring operations at 10 of the most promising sites. With a total of five months of continuous field operations, the expedition was the most comprehensive dedicated gas hydrate investigation ever undertaken.

  12. Direct measurement of methane hydrate composition along the hydrate equilibrium boundary

    Science.gov (United States)

    Circone, S.; Kirby, S.H.; Stern, L.A.

    2005-01-01

    The composition of methane hydrate, namely nW for CH 4??nWH2O, was directly measured along the hydrate equilibrium boundary under conditions of excess methane gas. Pressure and temperature conditions ranged from 1.9 to 9.7 MPa and 263 to 285 K. Within experimental error, there is no change in hydrate composition with increasing pressure along the equilibrium boundary, but nW may show a slight systematic decrease away from this boundary. A hydrate stoichiometry of n W = 5.81-6.10 H2O describes the entire range of measured values, with an average composition of CH4??5.99(??0.07) H2O along the equilibrium boundary. These results, consistent with previously measured values, are discussed with respect to the widely ranging values obtained by thermodynamic analysis. The relatively constant composition of methane hydrate over the geologically relevant pressure and temperature range investigated suggests that in situ methane hydrate compositions may be estimated with some confidence. ?? 2005 American Chemical Society.

  13. Moessbauer and calorimetric studies of portland cement hydration in the presence of black gram pulse

    International Nuclear Information System (INIS)

    Rai, Sarita; Kurian, Sajith; Dwivedi, V. N.; Das, S. S.; Singh, N. B.; Gajbhiye, N. S.

    2009-01-01

    Effect of different concentrations of naturally occurring admixture in the form of fine powder of black gram pulse (BGP) on the hydration of Portland cement was studied by isothermal calorimetry and 57 Fe Moessbauer spectroscopy. The spectra were recorded for anhydrous cement and the hydration products at room temperature and 77 K. In the presence of BGP, the spectra showed superparamagnetic doublets at room temperature and the sextet at 77 K, due to the presence of fine particles of iron containing component. Moessbauer studies of hydration products confirmed the formation of nanosize hydration products containing Fe 3+ . The isomer shift (δ) and the quadrupole splitting (ΔE Q ) values of C 4 AF in the cement confirmed iron in an octahedral and tetrahedral environment with +3 oxidation state. The high value of quadrupole splitting showed the high asymmetry of the electron environment around the iron atom. The overall mechanism of the hydration of cement in presence of BGP is discussed.

  14. Methamphetamine use among gay and bisexual men in Australia : Trends in recent and regular use from the Gay Community Periodic Surveys

    NARCIS (Netherlands)

    Lea, Toby; Mao, Limin; Hopwood, Max; Prestage, Garrett; Zablotska, Iryna; de Wit, John|info:eu-repo/dai/nl/06883652X; Holt, Martin

    BACKGROUND: Gay and bisexual men typically report high rates of illicit drug use, including methamphetamine use. This paper aimed to analyse trends in crystal methamphetamine ('crystal') and powder methamphetamine ('speed') use among gay and bisexual men in Australia, and characterise the

  15. Viral Hepatitis: Information for Gay and Bisexual Men

    Science.gov (United States)

    VIRAL HEPATITIS Information for Gay and Bisexual Men What is viral hepatitis? Viral hepatitis is an infection of the liver caused by one of several ... each virus is spread in different ways. Are gay and bisexual men at risk for viral hepatitis? ...

  16. Novel nanotechnology for efficient production of binary clathrate hydrates of hydrogen and other compounds

    Energy Technology Data Exchange (ETDEWEB)

    Di Profio, P.; Arca, S.; Germani, R.; Savelli, G. [Perugia Univ., Perugia (Italy). Dept. of Chemistry, Center of Excellence on Innovative Nanostructured Materials

    2008-07-01

    The development of a hydrogen-based economy depends on finding ways to store hydrogen, but current hydrogen storage methods have significant disadvantages. One main challenge in storing sufficient amounts of hydrogen (up to 4 weight per cent) into a clathrate matrix is that of a kinetic origin, in that the mass transfer of hydrogen gas into clathrate structures is significantly limited by the macroscopic scale of the gas-liquid or gas-ice interfaces involved. This paper discussed the possibility of storing hydrogen in clathrate hydrates. It presented a newly developed method for preparing binary hydrogen hydrates that is based on the formation of amphiphile-aided nanoemulsions. Nanotechnology is used to reduce the size of hydrate particles to a few nanometers, thereby minimizing the kinetic hindrance to hydrate formation. This process has potential for increasing the amount of hydrogen stored, as it has provided ca. 1 weight per cent of hydrogen. Two new co-formers were also successfully tested, namely cyclopentane and tetrahydrothiophene. 23 refs., 10 figs.

  17. Identification of the hydrate gel phases present in phosphate-modified calcium aluminate binders

    Energy Technology Data Exchange (ETDEWEB)

    Chavda, Mehul A.; Bernal, Susan A. [Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Apperley, David C. [Solid-State NMR Group, Department of Chemistry, Durham University, Durham DH1 3LE (United Kingdom); Kinoshita, Hajime [Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Provis, John L., E-mail: j.provis@sheffield.ac.uk [Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2015-04-15

    The conversion of hexagonal calcium aluminate hydrates to cubic phases in hydrated calcium aluminate cements (CAC) can involve undesirable porosity changes and loss of strength. Modification of CAC by phosphate addition avoids conversion, by altering the nature of the reaction products, yielding a stable amorphous gel instead of the usual crystalline hydrate products. Here, details of the environments of aluminium and phosphorus in this gel were elucidated using solid-state NMR and complementary techniques. Aluminium is identified in both octahedral and tetrahedral coordination states, and phosphorus is present in hydrous environments with varying, but mostly low, degrees of crosslinking. A {sup 31}P/{sup 27}Al rotational echo adiabatic passage double resonance (REAPDOR) experiment showed the existence of aluminium–phosphorus interactions, confirming the formation of a hydrated calcium aluminophosphate gel as a key component of the binding phase. This resolves previous disagreements in the literature regarding the nature of the disordered products forming in this system.

  18. Transport of hydrate slurry at high water cut

    OpenAIRE

    Melchuna , Aline; Cameirão , Ana; Herri , Jean-Michel; Ouabbas , Yamina; Glenat , Philippe

    2014-01-01

    Poster; International audience; Oil transportation in pipelines at the end of field production life implies to flow high quantities of water which represents the dominant phase. The process of crystallization of gas hydrates in this system needs to be studied and compared to the opposite one widely studied in the literature where water is the dispersed phase. The laboratory is equipped with the Archimede flow loop where the hydrate crystallization and transport are monitored. The flow loop is...

  19. Gas hydrate in nature

    Science.gov (United States)

    Ruppel, Carolyn D.

    2018-01-17

    Gas hydrate is a naturally occurring, ice-like substance that forms when water and gas combine under high pressure and at moderate temperatures. Methane is the most common gas present in gas hydrate, although other gases may also be included in hydrate structures, particularly in areas close to conventional oil and gas reservoirs. Gas hydrate is widespread in ocean-bottom sediments at water depths greater than 300–500 meters (m; 984–1,640 feet [ft]) and is also present in areas with permanently frozen ground (permafrost). Several countries are evaluating gas hydrate as a possible energy resource in deepwater or permafrost settings. Gas hydrate is also under investigation to determine how environmental change may affect these deposits.

  20. Visibility that demystifies: gays, gender, and sex on television.

    Science.gov (United States)

    Netzley, Sara Baker

    2010-01-01

    A content analysis of 98 episodes of primetime entertainment programs on commercial broadcast and cable television stations from the 2005-2006 season showed that gay characters on television were more likely to be shown in sexual situations than straight characters, and women were more likely to be shown in same-sex sexual situations than men. In addition, gay characters were more likely to be depicted as sexually active on cable television than they were on commercial broadcast television, and they were more likely to be relegated to guest star status on commercial broadcast television than on cable television. The study also showed that gay characters made up 7.5% of all the characters studied. This study discusses the implications of these findings for gay and straight audiences.

  1. Internalized Homophobia and Drug Use in a National Cohort of Gay and Bisexual Men: Examining Depression, Sexual Anxiety, and Gay Community Attachment as Mediating Factors.

    Science.gov (United States)

    Moody, Raymond L; Starks, Tyrel J; Grov, Christian; Parsons, Jeffrey T

    2018-05-01

    The minority stress process of internalized homophobia (IH) has been associated with a range of adverse health outcomes among gay and bisexual men (GBM). However, evidence is mixed regarding the effect of IH on drug use, suggesting the potential role of multiple mediated pathways. Researchers have linked depression, sexual anxiety, and gay community attachment with IH. Depression, sexual anxiety, and gay community attachment have also been linked with drug use and drug-related problems suggesting potential mediating roles. A U.S. national sample of 1071 HIV-negative GBM completed at-home surveys, including measures of sociodemographic characteristics, IH, depression, sexual anxiety, gay community attachment, and drug use and associated problems. Adjusting for sociodemographic characteristics, depression mediated the association between IH and recent drug use. IH was positively associated with depression, and depression was positively associated with recent drug use. Gay community attachment partially mediated drug-related problems. IH had a positive direct association with drug-related problems and a negative direct association with gay community attachment. Gay community attachment had a positive association with drug-related problems. IH was positively associated with sexual anxiety, but sexual anxiety was not associated with either drug outcome. Efforts to reduce IH among HIV-negative GBM are likely to have a positive impact on mental health problems, as well as reduce risk for drug use and drug-related problems. Gay communities could provide the social support necessary for reducing IH; however, emphasis on community level interventions that address factors that increase risk for drug-related problems remains important.

  2. The analysis of magnesium oxide hydration in three-phase reaction system

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Xiaojia; Guo, Lin; Chen, Chen; Liu, Quan; Li, Tie; Zhu, Yimin, E-mail: ntp@dlmu.edu.cn

    2014-05-01

    In order to investigate the magnesium oxide hydration process in gas–liquid–solid (three-phase) reaction system, magnesium hydroxide was prepared by magnesium oxide hydration in liquid–solid (two-phase) and three-phase reaction systems. A semi-empirical model and the classical shrinking core model were used to fit the experimental data. The fitting result shows that both models describe well the hydration process of three-phase system, while only the semi-empirical model right for the hydration process of two-phase system. The characterization of the hydration product using X-Ray diffraction (XRD) and scanning electron microscope (SEM) was performed. The XRD and SEM show hydration process in the two-phase system follows common dissolution/precipitation mechanism. While in the three-phase system, the hydration process undergo MgO dissolution, Mg(OH){sub 2} precipitation, Mg(OH){sub 2} peeling off from MgO particle and leaving behind fresh MgO surface. - Graphical abstract: There was existence of a peeling-off process in the gas–liquid–solid (three-phase) MgO hydration system. - Highlights: • Magnesium oxide hydration in gas–liquid–solid system was investigated. • The experimental data in three-phase system could be fitted well by two models. • The morphology analysis suggested that there was existence of a peel-off process.

  3. Instrumented Pressure Testing Chamber (IPTC) Characterization of Methane Gas Hydrate-Bearing Pressure Cores Collected from the Methane Production Test Site in the Eastern Nankai Trough, Offshore Japan

    Science.gov (United States)

    Waite, W. F.; Santamarina, J. C.; Dai, S.; Winters, W. J.; Yoneda, J.; Konno, Y.; Nagao, J.; Suzuki, K.; Fujii, T.; Mason, D. H.; Bergeron, E.

    2014-12-01

    Pressure cores obtained at the Daini-Atsumi Knoll in the eastern Nankai Trough, the site of the methane hydrate production test completed by the Methane Hydrate Resources in Japan (MH21) project in March 2013, were recovered from ~300 meters beneath the sea floor at close to in situ pressure. Cores were subsequently stored at ~20 MPa and ~5°C, which maintained hydrate in the cores within stability conditions. Pressure core physical properties were measured at 10 MPa and ~6°C, also within the methane hydrate stability field, using the IPTC and other Pressure Core Characterization Tools (PCCTs). Discrete IPTC measurements were carried out in strata ranging from silty sands to clayey silts within the turbidite sequences recovered in the cores. As expected, hydrate saturations were greatest in more permeable coarser-grained layers. Key results include: 1) Where hydrate saturation exceeded 40% in sandy sediments, the gas hydrate binds sediment grains within the matrix. The pressure core analyses yielded nearly in situ mechanical properties despite the absence of effective stress in the IPTC. 2) In adjacent fine-grained sediment (hydrate saturation < 15%), hydrate did not significantly bind the sediment. IPTC results in these locations were consistent with the zero effective-stress limit of comparable measurements made in PCCT devices that are designed to restore the specimen's in situ effective stress. In sand-rich intervals with high gas hydrate saturations, the measured compressional and shear wave velocities suggest that hydrate acts as a homogeneously-distributed, load-bearing member of the bulk sediment. The sands with high gas hydrate saturations were prone to fracturing (brittle failure) during insertion of the cone penetrometer and electrical conductivity probes. Authors would like to express their sincere appreciation to MH21 and the Ministry of Economy, Trade and Industry for permitting this work to be disclosed at the 2014 Fall AGU meeting.

  4. Manufacture of Methane Hydrate using Carbon Nano Tubes

    International Nuclear Information System (INIS)

    Park, Sung Seek

    2010-02-01

    Methane hydrate is formed by physical binding between water molecule and gas such as methane, ethane, propane, or carbon dioxide, etc., which is captured in the cavities of water molecule under the specific temperature and pressure. More than 99% of naturally produced methane hydrate consists of methane, and is widely dispersed in the continental slope and continental Shelf of the Pacific and the Atlantic, the Antarctica etc. The reserve of fossil fuel is 500 billion carbon ton and the reserve of methane is 360 million carbon ton. The reserve of gas hydrate is more than 1 trillion carbon ton, which is twice the fossil fuel. Therefore, natural gas hydrate as a kind of gas hydrate is expected to replace fossil fuel as new energy source of 21st century. Also 1 m 3 hydrate of pure methane can be decomposed to the maximum of 216 m 3 methane at standard condition. If these characteristics of hydrate are reversely utilized, natural gas is fixed into water in the form of hydrate solid. Therefore, the hydrate is considered to be a great way to transport and store natural gas in large quantity. Especially the transportation cost is known to be 18∼25% less than the liquefied transportation. However, when natural gas hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. Therefore, for the practical purpose in the application, the present investigation focuses on the rapid production of hydrates and increases gas consumption by adding MWCNT and NaCl into pure water. The results show that the equilibrium pressure in seawater is more higher than that in pure water, and methane hydrate could be formed rapidly during pressurization if the subcooling is maintained at 9K or above in seawater and 8K or above in pure water, respectively. Also, amount of consumed gas volume in pure water is more higher that in seawater at the same experimental conditions

  5. Differential thermal, Thermogravimetric and X-ray diffraction investigation of hydration phases in cementitious waste form

    International Nuclear Information System (INIS)

    Khalil, M.Y.; Nagy, M.E.; El-Sourougy, M.R.; Zaki, A.A.

    1996-01-01

    Hydration phases of cement determine the final properties of the product. Adding other components to the cement paste may alter the final phases formed and affect properties of the hardened products. In this work ordinary portland cement and/or blast furnace slag cement were hardened with low-or intermediate-level radioactive liquid wastes and different additives. Hydration phases were investigated using differential thermal, thermogravimetric, and X-ray diffraction techniques. Low-and intermediate-level liquid wastes were found not to affect the hydration phases of cement. The addition of inorganic exchangers and latex were found to affect the hydration properties of the cement waste system. This resulted in a reduction of compressive strength. On the contrary, addition of epoxy also affected the hydration causing increase in compressive strength. 10 figs., 2 tabs

  6. The effect of the promiscuity stereotype on opposition to gay rights.

    Science.gov (United States)

    Pinsof, David; Haselton, Martie G

    2017-01-01

    Opposition to gay rights is prevalent in countries around the world. Recent correlational research suggests that opposition to gay rights may be driven by an interaction between one's own short-term mating orientation (i.e. willingness to engage in casual sex) and representations of gay people as sexually promiscuous. Here, we experimentally manipulated representations of gay men by randomly assigning participants to read one of two versions of a fictitious newspaper article, one of which contained faux scientific evidence confirming the stereotype that gay men are promiscuous, and the other containing faux scientific evidence refuting the stereotype. We found that the manipulation interacted with short-term mating orientation (STMO) to predict opposition to gay rights, such that low-STMO individuals (i.e. more averse to casual sex) exhibited more support for gay rights when assigned to read the stereotype-refuting article compared to the stereotype-confirming article, whereas high-STMO individuals (i.e. less averse to casual sex) were not significantly influenced by the manipulation. We discuss the implications of these findings for the study of antigay attitudes, as well as for recent societal changes in acceptance of homosexuality.

  7. Development of an offshore gas field: Hydrate and paraffin tests for ensuring continuous production; Entwicklung eines offshore Gasfelds - Hydrat- und Paraffinuntersuchungen zur Sicherstellung der kontinuierlichen Produktion

    Energy Technology Data Exchange (ETDEWEB)

    Zettlitzer, M.; Busch, M. [RWE Dea AG, Wietze (Germany)

    2005-07-01

    Production in offshore gas fields often requires transporting of undried raw gas through pipelines laid on, or in, the sea floor. This will cool the gas down - at worst to sea floor temperature, which may be as low as 4 C. This will cause condensation of the water and higher hydrocarbons. Two of the related problems are gone into here, i.e. potential formation of gas hydrates and potential paraffin deposits. The paraffin problem is relevant not only for crude gas transport but also - even more so - for gas conditioning in a freeze-dryer. (orig.)

  8. Introduction to the Gas Hydrate Master Project of Energy National Science and Technology Program of Taiwan

    Science.gov (United States)

    Yang, T. F.; Research Team of Gas Hydrate Project of CGS of Taiwan

    2011-12-01

    Bottom Simulating Reflectors (BSRs), which have been considered as one of major indicators of the gas hydrate in sub-seafloor, have been detected and widely distributed in offshore SW Taiwan. The Central Geological Survey of Taiwan launched a 4-year multidisciplinary gas hydrate investigation program in 2004 to explore the potential of gas hydrate resources in the area. The results indicate that enormous amounts of gas hydrate should occur beneath the seafloor, although none of solid gas hydrate samples have been found. Therefore, a second stage of another 4-year program started in 2008 to extend the studies/investigation. In the ongoing projects, some specific areas will be studied in detail to assess the components of gas hydrate petroleum system and provide a better assessment of the energy resource potential of gas hydrate in the target area. In addition to the field investigations, phase equilibrium of gas hydrate via experiment, theoretical modeling, and molecular simulations has also been studied. The results can provide insights into gas hydrate production technology. Considering the high potential energy resources, the committee of the energy national science and technology program suggests initiating a master project to plan the strategy and timeline for the gas hydrate exploration, exploitation and production in Taiwan. The plan will be introduced in this presentation.

  9. Canaries in the mine? Gay community, consumption and aspiration in neoliberal Washington, DC

    OpenAIRE

    Lewis, Nathaniel

    2016-01-01

    Gay men have been implicated in neoliberal urban development strategies (e.g. the creative city) as a ‘canary’ population that forecasts growth. Paradoxically, both neoliberal re-development of North American inner-cities and the ways in which gay men become neoliberalised as individuals contribute to the dissolution of urban gay communities. In contrast to discourses of homonormativity, which suggest that gay men’s declining attachments to gay communities stem from new equalities and consequ...

  10. Representação gay em corpus literário paralelo Gay representation in parallel literary corpus

    Directory of Open Access Journals (Sweden)

    Adail Sebastião Rodrigues Júnior

    2010-01-01

    Full Text Available Este artigo apresenta parte dos resultados de minha pesquisa de doutorado, com foco em como personagens gays e suas realidades de mundo são representados por meio da transitividade (HALLIDAY; MATTHIESSEN, 2004. Os corpora sob análise são uma coletânea de contos gays intitulada Stud (ANDROS, 1969 e sua tradução brasileira As Aventuras de um Garoto de Programa (ANDROS, 1998, re-textualizada quase trinta anos após a publicação do original nos Estados Unidos da América. Cinco excertos foram escolhidos a fim de mostrar como partes dos corpos dos personagens são usadas para representar suas realidades de mundo, o que aponta para o papel do corpo na constituição de relações sociais homossexuais no contexto dos anos 1960 nos EUA. De igual modo, a tradução, embora feita nos anos 1990 no Brasil, enfatiza o mesmo papel empregado pelos fragmentos dos corpos dos personagens. Os resultados, portanto, abrem novas possibilidades de discussão de como os gays são representados no discurso literário.This paper aims at presenting part of the results of my doctorate research, with a focus on how gay characters and their world realities are represented by means of transitivity (HALLIDAY; MATTHIESSEN, 2004. The corpora under analysis are a collection of gay short stories entitled Stud (ANDROS, 1969 and its Brazilian translation As Aventuras de um Garoto de Programa (ANDROS, 1998, re-textualized almost thirty years after the original publication in the United States of America. Five excerpts were chosen in order to show how parts of the characters' bodies are used to represent their world realities, which points to the role of the body in the constitution of homosexual social relations in the context of the 1960s in the U.S. Likewise, the translation, though rendered in the 1990s in Brazil, emphasizes the same role played by fragments of the characters' bodies. Thus, the results open new possibilities for discussing further how gays are represented

  11. Consuming My Way Gay

    Directory of Open Access Journals (Sweden)

    Matthew Eichler

    2012-07-01

    Full Text Available As members of consumerist societies, we are socialized into what it means to be good citizens and participate in society through our consumption. For many, this is taught in the home, yet for lesbian, gay, bisexual, transgender, and queer (LGBTQ individuals, home is often not a source of reliable information about our identities. As such, LGBTQ individuals turn to the marketplace to seek information about their sexual and gender identities. This autoethnographic account shares, through three vignettes, how coming out as a queer man is shaped by consumptive pedagogy—that is, learning through consumption. First, material goods are explored as the signifier of sexual orientation. Then, the gay bar as marketplace and the online marketplace for relationships are explored.

  12. Modeling the influence of limestone addition on cement hydration

    Directory of Open Access Journals (Sweden)

    Ashraf Ragab Mohamed

    2015-03-01

    Full Text Available This paper addresses the influence of using Portland limestone cement “PLC” on cement hydration by characterization of its microstructure development. The European Standard EN 197-1:2011 and Egyptian specification ESS 4756-1/2009 permit the cement to contain up to 20% ground limestone. The computational tools assist in better understanding the influence of limestone additions on cement hydration and microstructure development to facilitate the acceptance of these more economical and ecological materials. μic model has been developed to enable the modeling of microstructural evolution of cementitious materials. In this research μic model is used to simulate both the influence of limestone as fine filler, providing additional surfaces for the nucleation and growth of hydration products. Limestone powder also reacts relatively slow with hydrating cement to form monocarboaluminate (AFmc phase, similar to the mono-sulfoaluminate (AFm phase formed in ordinary Portland cement. The model results reveal that limestone cement has accelerated cement hydration rate, previous experimental results and computer model “cemhyd3d” are used to validate this model.

  13. Lesbian, Gay, Bisexual, and Transgender Persons and Tobacco Use

    Science.gov (United States)

    ... Division of Reproductive Health More CDC Sites Lesbian, Gay, Bisexual, and Transgender Persons and Tobacco Use Recommend ... and Influence Resources References People who are lesbian, gay, bisexual, or transgender (LGBT) include all races and ...

  14. Gay, Lesbian, Bisexual and Transgender Health: Stigma and Discrimination

    Science.gov (United States)

    ... their lives. The Effects of Negative Attitudes on Gay, Bisexual, and Other Men Who Have Sex with Men Some people may have negative attitudes toward gay, bisexual, and other men who have sex with ...

  15. Identity processes, threat, and interpersonal relations: accounts from British Muslim gay men.

    Science.gov (United States)

    Jaspal, Rusi; Cinnirella, Marco

    2012-01-01

    This study explores identity processes, identity threat, and interpersonal relations with other gay men in a qualitative interview study with a sample of young British Muslim gay men of Pakistani background. Transcripts were subjected to qualitative thematic analysis. Data were analyzed through the interpretive lens of Identity Process Theory. Three superordinate themes are reported: (a) self-continuity and the transition from straight to gay space; (b) interpersonal relations with other gay men and self- and other categorization; and (c) interpersonal contact or identification with White gay men as an identity enhancer. Theoretical and practical implications of the results are discussed.

  16. 78 FR 33957 - Lesbian, Gay, Bisexual, and Transgender Pride Month, 2013

    Science.gov (United States)

    2013-06-06

    ..., Gay, Bisexual, and Transgender Pride Month, 2013 By the President of the United States of America A... equality from founding promise into lasting reality. Lesbian, gay, bisexual, and transgender (LGBT... Constitution and the laws of the United States, do hereby proclaim June 2013 as Lesbian, Gay, Bisexual, and...

  17. Hydration water and microstructure in calcium silicate and aluminate hydrates

    International Nuclear Information System (INIS)

    Fratini, Emiliano; Ridi, Francesca; Chen, Sow-Hsin; Baglioni, Piero

    2006-01-01

    Understanding the state of the hydration water and the microstructure development in a cement paste is likely to be the key for the improvement of its ultimate strength and durability. In order to distinguish and characterize the reacted and unreacted water, the single-particle dynamics of water molecules in hydrated calcium silicates (C 3 S, C 2 S) and aluminates (C 3 A, C 4 AF) were studied by quasi-elastic neutron scattering, QENS. The time evolution of the immobile fraction represents the hydration kinetics and the mobile fraction follows a non-Debye relaxation. Less sophisticated, but more accessible and cheaper techniques, like differential scanning calorimetry, DSC, and near-infrared spectroscopy, NIR, were validated through QENS results and they allow one to easily and quantitatively follow the cement hydration kinetics and can be widely applied on a laboratory scale to understand the effect of additives (i.e., superplasticizers, cellulosic derivatives, etc) on the thermodynamics of the hydration process. DSC provides information on the free water index and on the activation energy involved in the hydration process while the NIR band at 7000 cm -1 monitors, at a molecular level, the increase of the surface-interacting water. We report as an example the effect of two classes of additives widely used in the cement industry: superplasticizers, SPs, and cellulose derivatives. SPs interact at the solid surface, leading to a consistent increment of the activation energy for the processes of nucleation and growth of the hydrated phases. In contrast, the cellulosic additives do not affect the nucleation and growth activation energy, but cause a significant increment in the water availability: in other words the hydration process is more efficient without any modification of the solid/liquid interaction, as also evidenced by the 1 H-NMR. Additional information is obtained by scanning electron microscopy (SEM), ultra small angle neutron scattering (USANS) and wide

  18. Formation and dissociation of CO{sub 2} and CO{sub 2}-THF hydrates compared to CH{sub 4} and CH{sub 4}-THF hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Giavarini, C.; Maccioni, F.; Broggi, A. [Roma Univ. La Sapienza, Roma (Italy). Dept. of Chemical Engineering; Politi, M. [ENEL-RICERCHE, Brindisi (Italy)

    2008-07-01

    Carbon sequestration involves the removal of greenhouse gases from industrial or utility plant streams and their long term storage so that they cannot interact with the climate system. Different methods for selective carbon dioxide (CO{sub 2}) removal are in commercial use and are based on, gas absorption, membrane process, and cryogenic fractionation. In addition, disposal of captured CO{sub 2} in the ocean and in geological reservoirs has been proposed by researchers. Another challenge is to take advantage of the properties of CO{sub 2} hydrates for carbon sequestration since it could have a number of uses such as chemical production. As such, it is important to understand the hydrate decomposition kinetics during storage, transportation, and disposal. This paper presented a project that involved the separation of carbon dioxide from the flue gases of powers plants, in the form of hydrate. The project also involved the storage, use, and disposal of the hydrate. The purpose of the study was to evaluate the decomposition kinetics of CO{sub 2} hydrate containing different quantities of ice, at low pressures and temperatures between -3 and 0 degrees Celsius. In addition, in order to evaluate the tetrahydrofuran (THF) stabilization effect, the study examined the influence of THF on the formation and decomposition kinetics of mixed THF-methane (CH{sub 4}) and THF-CO{sub 2} hydrates. Preservation tests were conducted to determine the best pressure and temperature conditions for the mixed-hydrates conservation, with reference to the simple hydrates. The paper described the apparatus for the formation and dissociation tests which consisted of a jacketed stainless steel reactor, equipped with stirrer. The paper also described the hydrate formation procedure as well as hydrate characterization. Last, the paper discussed the hydrate dissociation tests that were conducted immediately after hydrate formation in the reactor. It was concluded that the hydrophilic and hydrophobic

  19. Novel understanding of calcium silicate hydrate from dilute hydration

    KAUST Repository

    Zhang, Lina; Yamauchi, Kazuo; Li, Zongjin; Zhang, Xixiang; Ma, Hongyan; Ge, Shenguang

    2017-01-01

    The perspective of calcium silicate hydrate (C-S-H) is still confronting various debates due to its intrinsic complicated structure and properties after decades of studies. In this study, hydration at dilute suspension of w/s equaling to 10

  20. Quantification of synthesized hydration products using synchrotron microtomography and spectral analysis

    Energy Technology Data Exchange (ETDEWEB)

    Deboodt, Tyler; Ideker, Jason H.; Isgor, O. Burkan; Wildenschild, Dorthe

    2017-12-01

    The use of x-ray computed tomography (CT) as a standalone method has primarily been used to characterize pore structure, cracking and mechanical damage in cementitious systems due to low contrast in the hydrated phases. These limitations have resulted in the inability to extract quantifiable information on such phases. The goal of this research was to address the limitations caused by low contrast and improving the ability to distinguish the four primary hydrated phases in portland cement; C-S-H, calcium hydroxide, monosulfate, and ettringite. X-ray CT on individual layers, binary mixtures of phases, and quaternary mixtures of phases to represent a hydrated portland cement paste were imaged with synchrotron radiation. Known masses of each phase were converted to a volume and compared to the segmented image volumes. It was observed that adequate contrast in binary mixing of phases allowed for segmentation, and subsequent image analysis indicated quantifiable volumes could be extracted from the tomographic volume. However, low contrast was observed when C-S-H and monosulfate were paired together leading to difficulties segmenting in an unbiased manner. Quantification of phases in quaternary mixtures included larger errors than binary mixes due to histogram overlaps of monosulfate, C-S-H, and calcium hydroxide.

  1. Not STRAIGHT forward for gays: A look at the lived experiences of gay men, living in Cape Town, with regard to their worker roles.

    Science.gov (United States)

    Soeker, Shaheed; Bonn, Gerri-Lee; de Vos, Zahraa; Gobhozi, Thobile; Pape, Candice; Ribaudo, Shelly

    2015-06-05

    The South African constitution protects the rights of gays; however in the workplace gays experience discrimination and marginalization. As a result of marginalization they struggle to reach their potential regarding career development and the fulfilment of their worker role. The study explored the experiences and perceptions of gay males with regard to acquiring and maintaining their worker roles. The study is phenomenological and qualitative in design. Eleven of these men participated in two focus groups. One male participated in two in-depth interviews and one interview was conducted with a key informant. Three themes emerged: 1) Being boxed in, 2) The glass ceiling, 3) This is where I can wear my feather boa. The study findings clearly depicted the many barriers experienced by homosexual men and how this negatively impacts on their worker role. Minimal facilitatory factors exist, to assist gay males %in with regard to their worker role. It was found that homo-prejudice still exists in South Africa and its workplaces and has a negative impact not only on gay men's worker role but also their well-being. This significantly highlights the great need for occupational therapy intervention in the lives of these gay men, and their workplaces.

  2. Educating gay male youth: since when is pornography a path towards self-respect?

    Science.gov (United States)

    Kendall, Christopher N

    2004-01-01

    In 2000, in the case of Little Sisters Book and Art Emporium, the Canadian Supreme Court was asked to determine whether gay male pornography violated the sex equality protections guaranteed by the Canadian Charter of Rights and Freedoms. Throughout this case, gay male activists and academics emphasised the risk posed by antipornography legal strategies to the dissemination of materials intended to promote safer sexual behaviour. Other arguments were advanced that gay male pornography should not be restricted because it serves as a learning tool for young men and, in so doing, does much to reduce the alarming incidence of gay youth suicide. The author examines these assumptions within the context of the gay male pornography defended in Little Sisters. His conclusion is that the present gay male obsession with hyper-masculinity, best evidenced in the pornography now widely touted by some gay men as a source of gay male identity and freedom, undermines safer sexual practices and the self-respect needed to combat youth suicide. The author concludes that gay men must commit to a sexuality built on mutuality, respect and caring (i.e., an identity politic built around sex equality).

  3. Le tourisme gay : aller ailleurs pour être soi-même ?

    Directory of Open Access Journals (Sweden)

    Emmanuel Jaurand

    2010-02-01

    Full Text Available L’orientation dominante des études sur le tourisme, longtemps marquées par l’importance de la dimension économique et par un désintérêt pour les questions touchant au corps, au sexe ou au genre, explique le silence autour du tourisme gay (qui n’est pas le tourisme des gays jusqu’aux années 1990. Pourtant, ce tourisme identitaire existe depuis longtemps et sa visibilité se développe, surtout dans les pays développés occidentaux. La métaphore du voyage et la recherche du paradis (sexuel perdu sont au cœur de l’identité homosexuelle depuis le 19 e siècle. Le tourisme gay se caractérise par des structures (tour-opérateurs, hébergements, croisières… et des destinations spécifiques. Pour les gays il s’agit, dans l’espace-temps des vacances, propice au relâchement et à la recréation de soi, de fuir un monde structuré par le système hétérosexiste et de rejoindre les autres (gays. La recherche de la rencontre du semblable et la sexualisation assumée du tourisme gay, à travers la libération et la dénudation des corps, participent d’une véritable quête pour valider son identité de gay. Elles font que les destinations préférées par les gays sont les stations balnéaires et les grandes villes : elles sont en effet dotées d’espaces publics, d’équipements commerciaux et de formes d’hébergement fermées favorables aux interactions et à la réalisation d’une éphémère « communauté gay ». The mainstream orientation of tourism studies, focused on the sole economic dimension for a long time, without any interest for questions about the body, sex or gender, explains the silence surrounding gay tourism (which is not the tourism of gay men since the 1990s. However, this identity tourism has existed for a long time and its visibility is growing, especially in Western developed countries. The metaphor of the journey and the search for a (sexual paradise lost have been at the core of the

  4. What's Good about Being Gay? Perspectives from Youth

    Science.gov (United States)

    Harper, Gary W.; Brodsky, Asya; Bruce, Douglas

    2012-01-01

    This article explores gay and bisexual male adolescents' positive perceptions of their sexual orientation identity. In-depth qualitative interviews were conducted with an ethnically diverse sample of 63 gay/bisexual male adolescents in Chicago (N = 42) and Miami (N = 21). Data revealed two major conceptual categories: (1) positive personal…

  5. 77 FR 33599 - Lesbian, Gay, Bisexual, and Transgender Pride Month, 2012

    Science.gov (United States)

    2012-06-07

    ..., Gay, Bisexual, and Transgender Pride Month, 2012 By the President of the United States of America A... live and love as we see fit. The lesbian, gay, bisexual, and transgender (LGBT) community has written a... coverage to someone just because they are lesbian, gay, bisexual, or transgender. Because we understand...

  6. 75 FR 32079 - Lesbian, Gay, Bisexual, and Transgender Pride Month, 2010

    Science.gov (United States)

    2010-06-07

    ..., Gay, Bisexual, and Transgender Pride Month, 2010 By the President of the United States of America A... equality on behalf of the lesbian, gay, bisexual, and transgender (LGBT) community. This month, as we.... That is why we must give committed gay couples the same rights and responsibilities afforded to any...

  7. Properties and hydration of blended cements with steelmaking slag

    International Nuclear Information System (INIS)

    Kourounis, S.; Tsivilis, S.; Tsakiridis, P.E.; Papadimitriou, G.D.; Tsibouki, Z.

    2007-01-01

    The present research study investigates the properties and hydration of blended cements with steelmaking slag, a by-product of the conversion process of iron to steel. For this purpose, a reference sample and three cements containing up to 45% w/w steel slag were tested. The steel slag fraction used was the '0-5 mm', due to its high content in calcium silicate phases. Initial and final setting time, standard consistency, flow of normal mortar, autoclave expansion and compressive strength at 2, 7, 28 and 90 days were measured. The hydrated products were identified by X-ray diffraction while the non-evaporable water was determined by TGA. The microstructure of the hardened cement pastes and their morphological characteristics were examined by scanning electron microscopy. It is concluded that slag can be used in the production of composite cements of the strength classes 42.5 and 32.5 of EN 197-1. In addition, the slag cements present satisfactory physical properties. The steel slag slows down the hydration of the blended cements, due to the morphology of contained C 2 S and its low content in calcium silicates

  8. Coupled numerical modeling of gas hydrates bearing sediments from laboratory to field-scale conditions

    Science.gov (United States)

    Sanchez, M. J.; Santamarina, C.; Gai, X., Sr.; Teymouri, M., Sr.

    2017-12-01

    Stability and behavior of Hydrate Bearing Sediments (HBS) are characterized by the metastable character of the gas hydrate structure which strongly depends on thermo-hydro-chemo-mechanical (THCM) actions. Hydrate formation, dissociation and methane production from hydrate bearing sediments are coupled THCM processes that involve, amongst other, exothermic formation and endothermic dissociation of hydrate and ice phases, mixed fluid flow and large changes in fluid pressure. The analysis of available data from past field and laboratory experiments, and the optimization of future field production studies require a formal and robust numerical framework able to capture the very complex behavior of this type of soil. A comprehensive fully coupled THCM formulation has been developed and implemented into a finite element code to tackle problems involving gas hydrates sediments. Special attention is paid to the geomechanical behavior of HBS, and particularly to their response upon hydrate dissociation under loading. The numerical framework has been validated against recent experiments conducted under controlled conditions in the laboratory that challenge the proposed approach and highlight the complex interaction among THCM processes in HBS. The performance of the models in these case studies is highly satisfactory. Finally, the numerical code is applied to analyze the behavior of gas hydrate soils under field-scale conditions exploring different features of material behavior under possible reservoir conditions.

  9. Sexual Orientation of Adult Sons of Gay Fathers.

    Science.gov (United States)

    Bailey, J. Michael; And Others

    1995-01-01

    Examined the sexual orientation of 82 adult sons of 55 gay men. Found that more than 90% of the sons whose sexual orientation could be rated were heterosexual. Gay and heterosexual sons did not differ on potentially relevant variables such as length of time they had lived with their fathers. (MDM)

  10. Preservice Teacher Attitudes toward Gay and Lesbian Parents

    Science.gov (United States)

    Herbstrith, Julie C.; Tobin, Renée M.; Hesson-McInnis, Matthew S.; Schneider, W. Joel

    2013-01-01

    Gay and lesbian parents are raising an increasing number of children, but little is known about how these parents are viewed by school personnel. In this study, preservice teacher attitudes toward gay and lesbian parents were assessed using implicit, explicit, behavioral, and behavioroid measures. Implicit measures indicate that participants rated…

  11. Cognitive-Behavioral Erectile Dysfunction Treatment for Gay Men

    Science.gov (United States)

    Hart, Trevor A.; Schwartz, Danielle R.

    2010-01-01

    The purpose of the present paper is to assist cognitive-behavioral therapists who are treating erectile dysfunction among gay men. Little information is available to cognitive-behavioral therapists about the psychological and social effects of erectile dysfunction in this population, or how to incorporate the concerns of gay men with erectile…

  12. Some like it mellow: on gay men complicating pornography discourses.

    Science.gov (United States)

    Corneau, Simon; van der Meulen, Emily

    2014-01-01

    Despite the proliferation of writing on pornography generally, much of the literature that focuses on gay pornography specifically conforms to either a pro- or anti-porn framework. This overly simplistic dichotomy positions pornography as a homogeneous construct, albeit one that is either "good" or "bad." Even theorists who situate pornography on a continuum, with erotica at one end and hardcore at the other, tend to reify these discourses. Further, it is not uncommon for researchers to draw conclusions about the effects of pornography consumption without defining exactly what pornography is. This ethnographic research draws on qualitative interviews with 20 consumers' of gay pornography in Toronto, Canada. By using a thematic analysis to document the ways in which gay men define, distinguish, and conceptualize gay pornography, five definitional categories were developed: Mellow; Commercial; Raunch; Amateur; and Bareback. These broad conceptualizations are discussed in reference to writing on gay pornography. Our research results emphasize the importance of clear definitions of pornography within pornography research.

  13. Social and psychological creativity in gay male midlife identity management.

    Science.gov (United States)

    Hajek, Christopher

    2016-06-01

    This study utilizes a qualitative thematic analysis methodology and a social identity theory framework to explore ways in which early midlife gay men report enhancing their social identities through social and psychological creativity. Face-to-face, semi-structured interviews were conducted with forty early midlife gay men (aged 40-53) in four US cities. Men discussed the collective and individual essences of their age and gay identities, including attitudes, beliefs, and behaviours that they embraced to self-enhance at midlife. These discussions emphasized differences from the younger gay outgroup, often in the context of intergenerational interaction. Identified were three strategies (and seven substrategies) that summarized the ways that interviewees constructed their identities in the interest of self-enhancement, specifically in the context of intergenerational comparisons with younger gay men. These strategies may be considered as extensions to social creativity strategies presented in Tajfel and Turner's (Psychology of intergroup relations. Chicago, IL: Nelson, 1986: 7) social identity theory. © 2015 The British Psychological Society.

  14. A Queer analysis of the discursive construction of gay identity in ...

    African Journals Online (AJOL)

    In 2003 the book Gayle: the language of kinks and queens: a history and dictionary of gay language in South Africa was published, documenting more than 1400 lexical items used by South African gays and lesbians. Given that the field of gay language is an established discipline within sociolinguistic research elsewhere ...

  15. 76 FR 32853 - Lesbian, Gay, Bisexual, And Transgender Pride Month, 2011

    Science.gov (United States)

    2011-06-07

    ..., Gay, Bisexual, And Transgender Pride Month, 2011 By the President of the United States of America A Proclamation The story of America's Lesbian, Gay, Bisexual, and Transgender (LGBT) community is the story of..., Don't Tell'' policy. With this repeal, gay and lesbian Americans will be able to serve openly in our...

  16. Gas hydrate concentration and characteristics within Hydrate Ridge inferred from multicomponent seismic reflection data

    Science.gov (United States)

    Kumar, Dhananjay; Sen, Mrinal K.; Bangs, Nathan L.

    2007-12-01

    A seismic experiment composed of streamer and ocean bottom seismometer (OBS) surveys was conducted in the summer of 2002 at southern Hydrate Ridge, offshore Oregon, to map the gas hydrate distribution within the hydrate stability zone. Gas hydrate concentrations within the reservoir can be estimated with P wave velocity (Vp); however, we can further constrain gas hydrate concentrations using S wave velocity (Vs), and use Vs through its relationship to Vp (Vp/Vs) to reveal additional details such as gas hydrate form within the matrix (i.e., hydrate cements the grains, becomes part of the matrix frame or floats in pore space). Both Vp and Vs can be derived simultaneously by inverting multicomponent seismic data. In this study, we use OBS data to estimate seismic velocities where both gas hydrate and free gas are present in the shallow sediments. Once Vp and Vs are estimated, they are simultaneously matched with modeled velocities to estimate the gas hydrate concentration. We model Vp using an equation based on a modification of Wood's equation that incorporates an appropriate rock physics model and Vs using an empirical relation. The gas hydrate concentration is estimated to be up to 7% of the rock volume, or 12% of the pore space. However, Vp and Vs do not always fit the model simultaneously. Vp can vary substantially more than Vs. Thus we conclude that a model, in which higher concentrations of hydrate do not affect shear stiffness, is more appropriate. Results suggest gas hydrates form within the pore space of the sediments and become part of the rock framework in our survey area.

  17. "Gay Boy Talk" Meets "Girl Talk": HIV Risk Assessment Assumptions in Young Gay Men's Sexual Health Communication with Best Friends

    Science.gov (United States)

    Mutchler, Matt G.; McDavitt, Bryce

    2011-01-01

    Young adults, particularly young gay men (YGM), are vulnerable to human immunodeficiency virus (HIV). Yet, little is known about how YGM discuss sexual health issues with their friends ("gay boy talk"). We conducted semi-structured interviews with YGM and their best friends (11 YGM/YGM dyads and 13 YGM/heterosexual female dyads). In this paper, we…

  18. Molecular analysis of petroleum derived compounds that adsorb onto gas hydrate surfaces

    International Nuclear Information System (INIS)

    Borgund, Anna E.; Hoiland, Sylvi; Barth, Tanja; Fotland, Per; Askvik, Kjell M.

    2009-01-01

    Field observations have shown that some streams of water, gas and crude oil do not form gas hydrate plugs during petroleum production even when operating within thermodynamic conditions for hydrate formation. Also, when studied under controlled laboratory conditions, some oils are found to form hydrate dispersed systems whereas others form plugs. Oils with low tendency to form hydrate plugs are believed to contain natural hydrate plug inhibiting components (NICs) that adsorb onto the hydrate surface, making them less water-wet and preventing the particles from agglomerating into large hydrate clusters. The molecular structure of the NICs is currently unknown. In this work, hydrate adsorbing components were extracted from crude oils using freon hydrates as an extraction phase. The fractions were found to be enriched in polar material, and more polar material is associated with hydrates generated in biodegraded crude oils than in non-biodegraded oils. Various fractionation schemes and analytical techniques have been applied in the search for molecular characterisation. The average molecular weights were found to be approximately 500 g/mole. GC-MS chromatograms show a large UCM (Unresolved Complex Mixture). Thus, GC-MS has a limited potential for identification of compounds. A commercial biosurfactant was used as a model compound in the search for similar structures in the extracts. The results from analysis of the hydrate adsorbing components suggest that the type and structure are more important for hydrate morphology than the amount of material adsorbed.

  19. Social Marginalization and Internal Exclusion: Gay Men's Understandings and Experiences of Community.

    Science.gov (United States)

    O'Byrne, Patrick; Bryan, Alyssa; Hendriks, Andrew; Horvath, Cynthia; Bouchard, Christiane; Etches, Vera

    2014-03-01

    A total of 27 gay and bisexual men were interviewed about how they perceived the criminal prosecution of persons living with HIV who do not disclose their HIV status. The stories that emerged from the interviews raise questions about the nature of the gay community. The findings centre on the participants' descriptions of (1) the heterosexual meta-culture, (2) the locales of gay life, and (3) unsupportive elements in the gay community. Analysis of the interview data situates the gay community as a place of both inclusion and exclusion and as a heterogeneous environment. Copyright© by Ingram School of Nursing, McGill University.

  20. Why Parenthood, and Why Now? Gay Men's Motivations for Pursuing Parenthood

    Science.gov (United States)

    Goldberg, Abbie E.; Downing, Jordan B.; Moyer, April M.

    2012-01-01

    The current qualitative study of 35 preadoptive gay male couples (70 men) examined gay men's motivations to parent and their reasons for pursuing parenthood at the current time. Similar to heterosexual couples, gay men described a range of psychologically oriented reasons as shaping their decision to become parents. Some of these (e.g., desire to…

  1. Missing!: Picture Books Reflecting Gay and Lesbian Families

    Science.gov (United States)

    Rowell, Elizabeth H.

    2007-01-01

    Early childhood educators carefully reflect on the messages conveyed about family diversity in the materials they select to use. Picture books depicting gay and lesbian families can enhance the curriculum and make an important contribution to young children's development. Families comprised of same-sex parents or those who have gay and lesbian…

  2. Hydrate Phase Assemblages in Blends of Ye'elimite and Gypsum with Alite and Belite

    DEFF Research Database (Denmark)

    Pedersen, Malene Thostrup; Skibsted, Jørgen

    2016-01-01

    Calcium sulpho-aluminate (CSA) cements all contain ye’elimite, either as the main phase or in intermediate amounts, while they differ in their content of accessory phases. Belite is the main phase in most CSA cements, however, alite - CSA cements have been produced. The hydrate phases formed during...... and hydration kinetics. The improved understanding of the hydrate phase assemblages as well as the hydration kinetics for the model systems will form the fundamental basis for further optimizations of blended systems including ye’elimite with the aim of maximizing the reaction degree of the main clinker phases...... hydration of CSA cements depend on the type of CSA cement and the amount of gypsum added. The hydration reactions of the main phases are by themselves well documented, whereas the simultaneous hydration of CSA cement components is not fully understood in terms of hydration products and kinetics. To further...

  3. Mathematical Model and Simulation of Gas Hydrate Reservoir Decomposition by Depressurization Modèle mathématique et simulation de dépressurisation et de décompression d’un réservoir d’hydrates de méthane

    Directory of Open Access Journals (Sweden)

    Zhao J.

    2012-05-01

    Full Text Available The numerical model for the depressurization of methane hydrates in a confined reservoir is presented based on mass conservation in porous media, incorporating multiphase flow theory and kinetics of gas hydrate dissociation. The universal implicit difference method is adopted, and the corresponding computer program is developed. During the production of the hydrate reservoir, distribution and the physical changes are analyzed and the gas hydrate dissociation and gas production law are studied from the computation. A numerical simulation shows that the reservoir pressure is descending slowly, which benefits the stabilization of the reservoir and inevitably decreases the efficiency in the production of gas hydrates in the depressurizing process. The gas production rate is controlled by the well pressure. The results are presented to show how this model may be used to estimate a lower downhole pressure of the well for hydrate recovery and how these results depend on reservoir and hydrate properties. Le modèle numérique présenté ici simule la dépressurisation d’hydrates de méthane dans un réservoir confiné; il se base sur le principe de conservation de la masse en milieu poreux, en intégrant la théorie de l’écoulement polyphasique et la cinétique de dissociation des hydrates de méthane. La méthode implicite et universelle des différences finies est utilisée et le programme informatique qui s’y rapporte est développé. Lors de l’exploitation du réservoir d’hydrates de méthane, la répartition et les changements physiques sont analysés et les lois sur la dissociation des hydrates de méthane et la production de gaz sont étudiées à partir des calculs. Une simulation numérique montre que la pression dans le réservoir diminue lentement, ce qui permet au réservoir de se stabiliser et diminue inévitablement le rendement de l’exploitation d’hydrates de méthane lors du processus de dépressurisation. Le rythme de

  4. Application of empirical hydration distribution functions around polar atoms for assessing hydration structures of proteins

    International Nuclear Information System (INIS)

    Matsuoka, Daisuke; Nakasako, Masayoshi

    2013-01-01

    Highlights: ► Empirical distribution functions of water molecules in protein hydration are made. ► The functions measure how hydrogen-bond geometry in hydration deviate from ideal. ► The functions assess experimentally identified hydration structures of protein. - Abstract: To quantitatively characterize hydrogen-bond geometry in local hydration structures of proteins, we constructed a set of empirical hydration distribution functions (EHDFs) around polar protein atoms in the main and side chains of 11 types of hydrophilic amino acids (D. Matsuoka, M. Nakasako, Journal of Physical Chemistry B 113 (2009) 11274). The functions are the ensemble average of possible hydration patterns around the polar atoms, and describe the anisotropic deviations from ideal hydrogen bond geometry. In addition, we defined probability distribution function of hydration water molecules (PDFH) over the hydrophilic surface of a protein as the sum of EHDFs of solvent accessible polar protein atoms. The functions envelop most of hydration sites identified in crystal structures of proteins (D. Matsuoka, M. Nakasako, Journal of Physical Chemistry B 114 (2010) 4652). Here we propose the application of EHDFs and PDFHs for assessing crystallographically identified hydration structures of proteins. First, hydration water molecules are classified with respect to the geometry in hydrogen bonds in referring EHDFs. Difference Fourier electron density map weighted by PDFH of protein is proposed to identify easily density peaks as candidates of hydration water molecules. A computer program implementing those ideas was developed and used for assessing hydration structures of proteins

  5. Gas Hydrate Research Database and Web Dissemination Channel

    Energy Technology Data Exchange (ETDEWEB)

    Micheal Frenkel; Kenneth Kroenlein; V Diky; R.D. Chirico; A. Kazakow; C.D. Muzny; M. Frenkel

    2009-09-30

    To facilitate advances in application of technologies pertaining to gas hydrates, a United States database containing experimentally-derived information about those materials was developed. The Clathrate Hydrate Physical Property Database (NIST Standard Reference Database {number_sign} 156) was developed by the TRC Group at NIST in Boulder, Colorado paralleling a highly-successful database of thermodynamic properties of molecular pure compounds and their mixtures and in association with an international effort on the part of CODATA to aid in international data sharing. Development and population of this database relied on the development of three components of information-processing infrastructure: (1) guided data capture (GDC) software designed to convert data and metadata into a well-organized, electronic format, (2) a relational data storage facility to accommodate all types of numerical and metadata within the scope of the project, and (3) a gas hydrate markup language (GHML) developed to standardize data communications between 'data producers' and 'data users'. Having developed the appropriate data storage and communication technologies, a web-based interface for both the new Clathrate Hydrate Physical Property Database, as well as Scientific Results from the Mallik 2002 Gas Hydrate Production Research Well Program was developed and deployed at http://gashydrates.nist.gov.

  6. Coming out and Coming Back: Rural Gay Migration and the City

    Science.gov (United States)

    Annes, Alexis; Redlin, Meredith

    2012-01-01

    This research focuses on the complex meaning and role of the city in American and French rural gay men's imaginary and life experience. It explores how gay men who grew up in the country build their sense of self through back-and-forth movement from rural to urban spaces. Therefore, it questions traditional gay migration studies, which have often…

  7. Designing a reservoir flow rate experiment for the GOM hydrate JIP leg 2 LWD drilling

    Energy Technology Data Exchange (ETDEWEB)

    Gullapalli, I.; Silpngarmlert, S.; Reik, B.; Kamal, M.; Jones, E. [Chevron Energy Technology Co., San Ramon, CA (United States); Moridis, G. [Lawrence Berkeley National Laboratories, CA (United States); Collett, T. [United States Geological Survey, Reston, VA (United States)

    2008-07-01

    Studies have indicated that the Gulf of Mexico may contain large deep sea hydrate deposits. This paper provided details of short-term production profiles obtained from a geological model of hydrate deposits located in the Gulf area. A well test analysis tool was used to obtain the production parameters. Pressure transients from numerical simulations of various well test designs were used to provide estimates of important flow parameters. The aim of the study was to determine the type and duration of a well test capable of providing data to support the accurate modeling of gas hydrate deposits. Parameters studied in the test included the effects of permeability and hydrate saturation as a function of the duration of the flow test. Results indicated that production using a constant bottom hole pressure is an appropriate method of impacting hydrate dissociation by depressurization. However, changes in transient pressure plots could not be characterized in order to identify regions of varying saturation levels. Results suggested that the rate of effective water to effective gas was higher than rates obtained from relative permeability relations due to low gas saturation levels. Fluid saturation regions were in areas of low confidence in relative permeability curves. However, it was not possible to calculate absolute permeability of the reservoir for systems with short production periods. Further studies are needed to determine effective permeability using history matching and a hydrate simulator. 8 refs., 4 tabs., 27 figs.

  8. Gay-Straight Alliances: Understanding Their Impact on the Academic and Social Experiences of Lesbian, Gay, Bisexual, Transgender, and Questioning High School Students

    Science.gov (United States)

    McCormick, Adam; Schmidt, Kathryn; Clifton, Emily

    2015-01-01

    Few studies have examined the effectiveness of gay-straight alliances (GSAs) on the social and academic experiences of lesbian, gay, bisexual, transgender, and questioning (LGBTQ) youths. The limited research on GSAs suggests that they are associated with positive youth development and increased safety; however, little qualitative information…

  9. Numerical simulation of gas hydrate exploitation from subsea reservoirs in the Black Sea

    Science.gov (United States)

    Janicki, Georg; Schlüter, Stefan; Hennig, Torsten; Deerberg, Görge

    2017-04-01

    Natural gas (methane) is the most environmental friendly source of fossil energy. When coal is replace by natural gas in power production the emission of carbon dioxide is reduced by 50 %. The vast amount of methane assumed in gas hydrate deposits can help to overcome a shortage of fossil energy resources in the future. To increase their potential for energy applications new technological approaches are being discussed and developed worldwide. Besides technical challenges that have to be overcome climate and safety issues have to be considered before a commercial exploitation of such unconventional reservoirs. The potential of producing natural gas from subsea gas hydrate deposits by various means (e. g. depressurization and/or carbon dioxide injection) is numerically studied in the frame of the German research project »SUGAR - Submarine Gas Hydrate Reservoirs«. In order to simulate the exploitation of hydrate-bearing sediments in the subsea, an in-house simulation model HyReS which is implemented in the general-purpose software COMSOL Multiphysics is used. This tool turned out to be especially suited for the flexible implementation of non-standard correlations concerning heat transfer, fluid flow, hydrate kinetics, and other relevant model data. Partially based on the simulation results, the development of a technical concept and its evaluation are the subject of ongoing investigations, whereby geological and ecological criteria are to be considered. The results illustrate the processes and effects occurring during the gas production from a subsea gas hydrate deposit by depressurization. The simulation results from a case study for a deposit located in the Black Sea reveal that the production of natural gas by simple depressurization is possible but with quite low rates. It can be shown that the hydrate decomposition and thus the gas production strongly depend on the geophysical properties of the reservoir, the mass and heat transport within the reservoir, and

  10. In Situ Raman Analyses of Natural Gas and Gas Hydrates at Hydrate Ridge, Oregon

    Science.gov (United States)

    Peltzer, E. T.; White, S. N.; Dunk, R. M.; Brewer, P. G.; Sherman, A. D.; Schmidt, K.; Hester, K. C.; Sloan, E. D.

    2004-12-01

    During a July 2004 cruise to Hydrate Ridge, Oregon, MBARI's sea-going laser Raman spectrometer was used to obtain in situ Raman spectra of natural gas hydrates and natural gas venting from the seafloor. This was the first in situ analysis of gas hydrates on the seafloor. The hydrate spectra were compared to laboratory analyses performed at the Center for Hydrate Research, Colorado School of Mines. The natural gas spectra were compared to MBARI gas chromatography (GC) analyses of gas samples collected at the same site. DORISS (Deep Ocean Raman In Situ Spectrometer) is a laboratory model laser Raman spectrometer from Kaiser Optical Systems, Inc modified at MBARI for deployment in the deep ocean. It has been successfully deployed to depths as great as 3600 m. Different sampling optics provide flexibility in adapting the instrument to a particular target of interest. An immersion optic was used to analyze natural gas venting from the seafloor at South Hydrate Ridge ( ˜780 m depth). An open-bottomed cube was placed over the vent to collect the gas. The immersion optic penetrated the side of the cube as did a small heater used to dissociate any hydrate formed during sample collection. To analyze solid hydrates at both South and North Hydrate Ridge ( ˜590 m depth), chunks of hydrate were excavated from the seafloor and collected in a glass cylinder with a mesh top. A stand-off optic was used to analyze the hydrate inside the cylinder. Due to the partial opacity of the hydrate and the small focal volume of the sampling optic, a precision underwater positioner (PUP) was used to focus the laser spot onto the hydrate. PUP is a stand-alone system with three degrees-of-freedom, capable of moving the DORISS probe head with a precision of 0.1 mm. In situ Raman analyses of the gas indicate that it is primarily methane. This is verified by GC analyses of samples collected from the same site. Other minor constituents (such as CO2 and higher hydrocarbons) are present but may be in

  11. Ductile flow of methane hydrate

    Science.gov (United States)

    Durham, W.B.; Stern, L.A.; Kirby, S.H.

    2003-01-01

    Compressional creep tests (i.e., constant applied stress) conducted on pure, polycrystalline methane hydrate over the temperature range 260-287 K and confining pressures of 50-100 MPa show this material to be extraordinarily strong compared to other icy compounds. The contrast with hexagonal water ice, sometimes used as a proxy for gas hydrate properties, is impressive: over the thermal range where both are solid, methane hydrate is as much as 40 times stronger than ice at a given strain rate. The specific mechanical response of naturally occurring methane hydrate in sediments to environmental changes is expected to be dependent on the distribution of the hydrate phase within the formation - whether arranged structurally between and (or) cementing sediments grains versus passively in pore space within a sediment framework. If hydrate is in the former mode, the very high strength of methane hydrate implies a significantly greater strain-energy release upon decomposition and subsequent failure of hydrate-cemented formations than previously expected.

  12. Hydration rate of obsidian.

    Science.gov (United States)

    Friedman, I; Long, W

    1976-01-30

    The hydration rates of 12 obsidian samples of different chemical compositions were measured at temperatures from 95 degrees to 245 degrees C. An expression relating hydration rate to temperature was derived for each sample. The SiO(2) content and refractive index are related to the hydration rate, as are the CaO, MgO, and original water contents. With this information it is possible to calculate the hydration rate of a sample from its silica content, refractive index, or chemical index and a knowledge of the effective temperature at which the hydration occurred. The effective hydration temperature can be either measured or approximated from weather records. Rates have been calculated by both methods, and the results show that weather records can give a good approximation to the true EHT, particularly in tropical and subtropical climates. If one determines the EHT by any of the methods suggested, and also measures or knows the rate of hydration of the particular obsidian used, it should be possible to carry out absolute dating to +/- 10 percent of the true age over periods as short as several years and as long as millions of years.

  13. Investigation of the Methane Hydrate Formation by Cavitation Jet

    Science.gov (United States)

    Morita, H.; Nagao, J.

    2015-12-01

    Methane hydrate (hereafter called "MH") is crystalline solid compound consisting of hydrogen-bonded water molecules forming cages and methane gas molecules enclosed in the cage. When using MH as an energy resource, MH is dissociated to methane gas and water and collect only the methane gas. The optimum MH production method was the "depressurization method". Here, the production of MH means dissociating MH in the geologic layers and collecting the resultant methane gas by production systems. In the production of MH by depressurization method, MH regeneration was consider to important problem for the flow assurance of MH production system. Therefore, it is necessary to clarify the effect of flow phenomena in the pipeline on hydrate regeneration. Cavitation is one of the flow phenomena which was considered a cause of MH regeneration. Large quantity of microbubbles are produced by cavitation in a moment, therefore, it is considered to promote MH formation. In order to verify the possible of MH regeneration by cavitation, it is necessary to detailed understanding the condition of MH formation by cavitation. As a part of a Japanese National hydrate research program (MH21, funded by METI), we performed a study on MH formation using by cavitation. The primary objective of this study is to demonstrate the formation MH by using cavitation in the various temperature and pressure condition, and to clarify the condition of MH formation by using observation results.

  14. Hydration kinetics of cement composites with varying water-cement ratio using terahertz spectroscopy

    Science.gov (United States)

    Ray, Shaumik; Dash, Jyotirmayee; Devi, Nirmala; Sasmal, Saptarshi; Pesala, Bala

    2015-03-01

    Cement is mixed with water in an optimum ratio to form concrete with desirable mechanical strength and durability. The ability to track the consumption of major cement constituents, viz., Tri- and Dicalcium Silicates (C3S, C2S) reacting with water along with the formation of key hydration products, viz., Calcium-Silicate-Hydrate (C-S-H) which gives the overall strength to the concrete and Calcium Hydroxide (Ca(OH)2), a hydration product which reduces the strength and durability, using an efficient technique is highly desirable. Optimizing the amount of water to be mixed with cement is one of the main parameters which determine the strength of concrete. In this work, THz spectroscopy has been employed to track the variation in hydration kinetics for concrete samples with different water-cement ratios, viz., 0.3, 0.4, 0.5 and 0.6. Results show that for the sample with water-cement ratio of 0.3, significant amount of the C3S and C2S remain unreacted even after the initial hydration period of 28 days while for the cement with water-cement ratio of 0.6, most of the constituents get consumed during this stage. Analysis of the formation of Ca(OH)2 has been done which shows that the concrete sample with water-cement ratio of 0.6 produces the highest amount of Ca(OH)2 due to higher consumption of C3S/C2S in presence of excess water which is not desirable. Samples with water-cement ratio of 0.4 and 0.5 show more controlled reaction during the hydration which can imply formation of an optimized level of desired hydration products resulting in a more mechanically strong and durable concrete.

  15. Gay-Lussac Experiment

    Science.gov (United States)

    Ladino, L. A.; Rondón, S. H.

    2015-01-01

    In this paper, we present a low-cost method to study the Gay-Lussac's law. We use a heating wire wrapped around the test tube to heat the air inside and make use of a solid state pressure sensor which requires a previous calibration to measure the pressure in the test tube.

  16. Origins of saccharide-dependent hydration at aluminate, silicate, and aluminosilicate surfaces.

    Science.gov (United States)

    Smith, Benjamin J; Rawal, Aditya; Funkhouser, Gary P; Roberts, Lawrence R; Gupta, Vijay; Israelachvili, Jacob N; Chmelka, Bradley F

    2011-05-31

    Sugar molecules adsorbed at hydrated inorganic oxide surfaces occur ubiquitously in nature and in technologically important materials and processes, including marine biomineralization, cement hydration, corrosion inhibition, bioadhesion, and bone resorption. Among these examples, surprisingly diverse hydration behaviors are observed for oxides in the presence of saccharides with closely related compositions and structures. Glucose, sucrose, and maltodextrin, for example, exhibit significant differences in their adsorption selectivities and alkaline reaction properties on hydrating aluminate, silicate, and aluminosilicate surfaces that are shown to be due to the molecular architectures of the saccharides. Solid-state (1)H, (13)C, (29)Si, and (27)Al nuclear magnetic resonance (NMR) spectroscopy measurements, including at very high magnetic fields (19 T), distinguish and quantify the different molecular species, their chemical transformations, and their site-specific adsorption on different aluminate and silicate moieties. Two-dimensional NMR results establish nonselective adsorption of glucose degradation products containing carboxylic acids on both hydrated silicates and aluminates. In contrast, sucrose adsorbs intact at hydrated silicate sites and selectively at anhydrous, but not hydrated, aluminate moieties. Quantitative surface force measurements establish that sucrose adsorbs strongly as multilayers on hydrated aluminosilicate surfaces. The molecular structures and physicochemical properties of the saccharides and their degradation species correlate well with their adsorption behaviors. The results explain the dramatically different effects that small amounts of different types of sugars have on the rates at which aluminate, silicate, and aluminosilicate species hydrate, with important implications for diverse materials and applications.

  17. (Re)locating the gay Filipino: resistance, postcolonialism, and identity.

    Science.gov (United States)

    Manalansan, M F

    1993-01-01

    This paper attempts to critically analyze issues of postcolonial displacement, immigration, and homosexuality by examining the works of two Filipino gay immigrant writers, John Silva and Ralph Peña. Using postcolonial and critical theories, anthropological studies, and ethnographic fieldwork in New York City, this paper focuses on the role of language, memory, the body, race/ethnicity, and social class in the narrative strategies of the two writers. This paper argues that gay postcolonial writers such as these two relocate and reconfigure homosexual/gay identity in the face of new and oppressive hierarchies, identities, and practices.

  18. Overview: Nucleation of clathrate hydrates.

    Science.gov (United States)

    Warrier, Pramod; Khan, M Naveed; Srivastava, Vishal; Maupin, C Mark; Koh, Carolyn A

    2016-12-07

    Molecular level knowledge of nucleation and growth of clathrate hydrates is of importance for advancing fundamental understanding on the nature of water and hydrophobic hydrate formers, and their interactions that result in the formation of ice-like solids at temperatures higher than the ice-point. The stochastic nature and the inability to probe the small length and time scales associated with the nucleation process make it very difficult to experimentally determine the molecular level changes that lead to the nucleation event. Conversely, for this reason, there have been increasing efforts to obtain this information using molecular simulations. Accurate knowledge of how and when hydrate structures nucleate will be tremendously beneficial for the development of sustainable hydrate management strategies in oil and gas flowlines, as well as for their application in energy storage and recovery, gas separation, carbon sequestration, seawater desalination, and refrigeration. This article reviews various aspects of hydrate nucleation. First, properties of supercooled water and ice nucleation are reviewed briefly due to their apparent similarity to hydrates. Hydrate nucleation is then reviewed starting from macroscopic observations as obtained from experiments in laboratories and operations in industries, followed by various hydrate nucleation hypotheses and hydrate nucleation driving force calculations based on the classical nucleation theory. Finally, molecular simulations on hydrate nucleation are discussed in detail followed by potential future research directions.

  19. Overview: Nucleation of clathrate hydrates

    Science.gov (United States)

    Warrier, Pramod; Khan, M. Naveed; Srivastava, Vishal; Maupin, C. Mark; Koh, Carolyn A.

    2016-12-01

    Molecular level knowledge of nucleation and growth of clathrate hydrates is of importance for advancing fundamental understanding on the nature of water and hydrophobic hydrate formers, and their interactions that result in the formation of ice-like solids at temperatures higher than the ice-point. The stochastic nature and the inability to probe the small length and time scales associated with the nucleation process make it very difficult to experimentally determine the molecular level changes that lead to the nucleation event. Conversely, for this reason, there have been increasing efforts to obtain this information using molecular simulations. Accurate knowledge of how and when hydrate structures nucleate will be tremendously beneficial for the development of sustainable hydrate management strategies in oil and gas flowlines, as well as for their application in energy storage and recovery, gas separation, carbon sequestration, seawater desalination, and refrigeration. This article reviews various aspects of hydrate nucleation. First, properties of supercooled water and ice nucleation are reviewed briefly due to their apparent similarity to hydrates. Hydrate nucleation is then reviewed starting from macroscopic observations as obtained from experiments in laboratories and operations in industries, followed by various hydrate nucleation hypotheses and hydrate nucleation driving force calculations based on the classical nucleation theory. Finally, molecular simulations on hydrate nucleation are discussed in detail followed by potential future research directions.

  20. Race Fucker: representações raciais na pornografia gay Race Fucker: racial representations in gay pornography

    Directory of Open Access Journals (Sweden)

    Osmundo Pinho

    2012-06-01

    Full Text Available Neste estudo, procuro explorar determinada perspectiva crítica relacionada à articulação entre raça, sexualidade e gênero, entendendo que a pornografia gay se prestaria exemplarmente a flagrar a produção de um sistema ordenado de classificações e categorias, estereótipos e representações, instituídos como um discurso capaz de ser lido como o inventário da fetichização socialmente produzida para o desejo sexual racializado. Para desenvolver essa perspectiva apresento uma breve discussão teórica sobre a pornografia, interrogada pela articulação prazer/poder e a leitura de três conjuntos êmicos de representação racial associados ao desejo homossexual: a negritude, a branquidade e a brasilidade.In this study the author seeks to explore a specific critical perspective related to the race, sexuality and gender articulation, understanding that gay pornography will be exemplary to show the production of a coordinated system of classifications and categories, stereotypes and representations built as a discourse that may be read as a socially produced inventory of fetichization for racialized sexual desire. In order to develop this view the author presents a short theoretical discussion on pornography, interrogated by the power/pleasure articulation and the reading of three hemic corpora of racial representation related to homosexual desire: blackness, whiteness and brazilianness.

  1. Measurements of gas permeability and non-Darcy flow in gas-water-hydrate systems

    Energy Technology Data Exchange (ETDEWEB)

    Ersland, G.; Husebo, J.; Graue, A.; Kvamme, B. [Bergen Univ., Bergen (Norway). Dept. of Physics and Technology; Baldwin, B. [Green Country Petrophysics LLC, Dewey, OK (United States); Stevens, J.; Howard, J. [ConocoPhillips, OK (United States)

    2008-07-01

    Storage of carbon dioxide (CO{sub 2}) in natural gas hydrate reservoirs may offer stable long-term storage of a greenhouse gas while benefiting from methane production, without requiring heat. By exposing hydrate to a thermodynamically preferred hydrate former, CO{sub 2}, the hydrate may be maintained macroscopically in the solid state and retain the stability of the formation. However, there is concern over the flow capacity in such reservoirs. This depends on several factors, notably thermodynamic destabilization of hydrate in small pores due to capillary effects; the presence of liquid channels separating the hydrate from the mineral surfaces; and, the connectivity of gas or liquid filled pores and channels. This paper described a technique for measuring gas permeability in gas-water-hydrate systems. It reported on several experiments that measured gas permeability during stages of hydrate growth in sandstone core plugs. Interactions between minerals and surrounding molecules were also discussed. The formation of methane hydrate in porous media was monitored and quantified with magnetic resonance imaging (MRI). MRI images of hydrate growth within the porous rock were provided along with measurements of gas permeability and non-Darcy flow effects at various hydrate saturations. Gas permeability was measured at steady state flow of methane through the hydrate-bearing core sample. Significant gas permeability was recorded for porous sandstone even when hydrates occupied up to 60 per cent of the pore space. It was concluded that MRI imaging can be used effectively to map and quantify hydrate saturation in sandstone core plugs. 27 refs., 2 tabs., 10 figs.

  2. Exogenous origin of hydration on asteroid (16) Psyche: the role of hydrated asteroid families

    Science.gov (United States)

    Avdellidou, C.; Delbo', M.; Fienga, A.

    2018-04-01

    Asteroid (16) Psyche, which for a long time was the largest M-type with no detection of hydration features in its spectrum, was recently discovered to have a weak 3-μm band and thus it was eventually added to the group of hydrated asteroids. Its relatively high density, in combination with the high radar albedo, led researchers to classify the asteroid as a metallic object. It is believed that it is possibly a core of a differentiated body, a remnant of `hit-and-run' collisions. The detection of hydration is, in principle, inconsistent with a pure metallic origin for this body. Here, we consider the scenario in which the hydration on its surface is exogenous and was delivered by hydrated impactors. We show that impacting asteroids that belong to families whose members have the 3-μm band can deliver hydrated material to Psyche. We developed a collisional model with which we test all dark carbonaceous asteroid families, which contain hydrated members. We find that the major source of hydrated impactors is the family of Themis, with a total implanted mass on Psyche of the order of ˜1014 kg. However, the hydrated fraction could be only a few per cent of the implanted mass, as the water content in carbonaceous chondrite meteorites, the best analogue for the Themis asteroid family, is typically a few per cent of their mass.

  3. Study of methane hydrate as a future energy resource: low emission extraction and power generation

    Science.gov (United States)

    Chen, L.; Yamada, H.; Kanda, Y.; Sasaki, H.; Okajima, J.; Iga, Y.; Komiya, A.; Maruyama, S.

    2016-08-01

    With the fast increase of world energy consumption in recent years, new and sustainable energy sources are becoming more and more important. Methane Hydrate is one promising candidate for the future energy supply of humankind, due to its vast existence in permafrost regions and near-coast seabed. This study is focused on the effective low emission utilization of methane hydrate from deep seabed. The Nankai Trough of Japan is taken as the target region in this study for methane hydrate extraction and utilization system design. Low emission system and power generation system with CCS (Carbon Capture and Sequestration) processes are proposed and analyzed for production rate and electricity generation efficiency problem study. It is found that the gas production price can reach the current domestic natural gas supply price level if the production rate can be improved. The optimized system is estimated to have power efficiency about 35%. In addition, current development and analysis from micro-to-macro scale methane hydrate production and dissociation dynamics are also discussed into detail in this study.

  4. Relationship Preferences Among Gay and Lesbian Online Daters : Individual and Contextual Influences

    NARCIS (Netherlands)

    Potarca, Gina; Mills, Melinda; Neberich, Wiebke

    There is currently little knowledge about what gay men and lesbians seek in a romantic relationship. This study extends the literature on gay men and lesbians' partnership preferences by engaging in the first large-scale empirical study of the long-term dating intentions and monogamy beliefs of gay

  5. Why Parenthood, and Why Now?: Gay Men's Motivations for Pursuing Parenthood.

    Science.gov (United States)

    Goldberg, Abbie E; Downing, Jordan B; Moyer, April M

    2012-02-01

    The current qualitative study of 35 pre-adoptive gay male couples (70 men) examined gay men's motivations to parent and their reasons for pursuing parenthood at the current time. Similar to heterosexual couples, gay men described a range of psychologically-oriented reasons as shaping their decision to become parents. Some of these (e.g., desire to teach a child tolerance) may have been uniquely shaped by their sexual minority status, and others (e.g., desire to give a child a good home) in part reflect their adoptive status. Men named age, finances, and relationship factors, as well as unique contextual factors such as the need to find and move to gay-friendly neighborhoods, as influencing their readiness to pursue parenthood at the current time. Gay men's motivations to parent echo normative life course decision-making processes, but also reflect concerns that are uniquely informed by their sexual minority status.

  6. Isostructural and cage-specific replacement occurring in sII hydrate with external CO2/N2 gas and its implications for natural gas production and CO2 storage

    International Nuclear Information System (INIS)

    Seo, Young-ju; Park, Seongmin; Kang, Hyery; Ahn, Yun-Ho; Lim, Dongwook; Kim, Se-Joon; Lee, Jaehyoung; Lee, Joo Yong; Ahn, Taewoong; Seo, Yongwon; Lee, Huen

    2016-01-01

    structural sustainability and cage-specific replacement observed in the C 3 H 8 + CH 4 hydrate with external CO 2 /N 2 gas will have significant implications for suggesting target gas hydrate reservoirs and understanding the precise nature of guest exchange in gas hydrates for both safe natural gas production and long-term CO 2 sequestration.

  7. Direct measurements of 3d structure, chemistry and mass density during the induction period of C3s hydration

    International Nuclear Information System (INIS)

    Hu, Qinang; Aboustait, Mohammed; Kim, Taehwan; Ley, M. Tyler; Bullard, Jeffrey W.; Scherer, George; Hanan, Jay C.; Rose, Volker; Winarski, Robert; Gelb, Jeffrey

    2016-01-01

    The reasons for the start and end of the induction period of cement hydration remain a topic of controversy. One long-standing hypothesis is that a thin metastable hydrate forming on the surface of cement grains significantly reduces the particle dissolution rate; the eventual disappearance of this layer re-establishes higher dissolution rates at the beginning of the acceleration period. However, the importance, or even the existence, of this metastable layer has been questioned because it cannot be directly detected in most experiments. In this work, a combined analysis using nano-tomography and nano-X-ray fluorescence makes the direct imaging of early hydration products possible. These novel X-ray imaging techniques provide quantitative measurements of 3D structure, chemical composition, and mass density of the hydration products during the induction period. This work does not observe a low density product on the surface of the particle, but does provide insights into the formation of etch pits and the subsequent hydration products that fill them.

  8. Preservice elementary teacher's attitudes toward gay and lesbian parenting.

    Science.gov (United States)

    Maney, D W; Cain, R E

    1997-08-01

    This preliminary investigation assessed preservice elementary teacher's attitudes toward homosexual parents and their children. The study populations included 195 college students enrolled in an elementary school health methods course at a large northeastern university. A 51-item " and Lesbian Parenting Questionnaire" was used for data collection purposes. Reliability estimates for the scales were: attitudes toward lesbians and gay men (alpha = .90), comfort toward gay and lesbian families (alpha = .92), and knowledge about homosexuality (alpha = .52). Most respondents agreed gay men: were not disgusting, should be allowed to teach, were not perverted, and should not overcome their feelings of homosexuality. Most respondents disagreed lesbians cannot fit into society or were sick. Nearly all agreed female homosexuality should not be a basis for job discrimination. Females were significantly (p attitudes toward gay fathers than did male respondents. Respondents with stronger religious attitudes had significantly (p attitudes toward lesbian parents than respondents with weaker religious attitudes.

  9. Teenage Queerness: Negotiating Heteronormativity in the Representation of Gay Teenagers in "Glee"

    Science.gov (United States)

    Dhaenens, Frederik

    2013-01-01

    Despite a significant increase in gay representation in contemporary television fiction, many media scholars argue that the representation of gay men and women is governed by heteronormativity. They postulate that even rounded and heterogeneous representations of gay men and women are characters that desire to participate in institutions,…

  10. Tetrafluoroethane (R134a) hydrate formation within variable volume reactor accompanied by evaporation and condensation

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, K.; Choo, Y. S.; Hong, H. J.; Yoon, Y. S.; Song, M. H., E-mail: songm@dgu.edu [Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, Seoul 100-715 (Korea, Republic of)

    2015-03-15

    Vast size hydrate formation reactors with fast conversion rate are required for the economic implementation of seawater desalination utilizing gas hydrate technology. The commercial target production rate is order of thousand tons of potable water per day per train. Various heat and mass transfer enhancement schemes including agitation, spraying, and bubbling have been examined to maximize the production capacities in scaled up design of hydrate formation reactors. The present experimental study focused on acquiring basic knowledge needed to design variable volume reactors to produce tetrafluoroethane hydrate slurry. Test vessel was composed of main cavity with fixed volume of 140 ml and auxiliary cavity with variable volume of 0 ∼ 64 ml. Temperatures at multiple locations within vessel and pressure were monitored while visual access was made through front window. Alternating evaporation and condensation induced by cyclic volume change provided agitation due to density differences among water and vapor, liquid and hydrate R134a as well as extended interface area, which improved hydrate formation kinetics coupled with latent heat release and absorption. Influences of coolant temperature, piston stroke/speed, and volume change period on hydrate formation kinetics were investigated. Suggestions of reactor design improvement for future experimental study are also made.

  11. Tetrafluoroethane (R134a) hydrate formation within variable volume reactor accompanied by evaporation and condensation

    International Nuclear Information System (INIS)

    Jeong, K.; Choo, Y. S.; Hong, H. J.; Yoon, Y. S.; Song, M. H.

    2015-01-01

    Vast size hydrate formation reactors with fast conversion rate are required for the economic implementation of seawater desalination utilizing gas hydrate technology. The commercial target production rate is order of thousand tons of potable water per day per train. Various heat and mass transfer enhancement schemes including agitation, spraying, and bubbling have been examined to maximize the production capacities in scaled up design of hydrate formation reactors. The present experimental study focused on acquiring basic knowledge needed to design variable volume reactors to produce tetrafluoroethane hydrate slurry. Test vessel was composed of main cavity with fixed volume of 140 ml and auxiliary cavity with variable volume of 0 ∼ 64 ml. Temperatures at multiple locations within vessel and pressure were monitored while visual access was made through front window. Alternating evaporation and condensation induced by cyclic volume change provided agitation due to density differences among water and vapor, liquid and hydrate R134a as well as extended interface area, which improved hydrate formation kinetics coupled with latent heat release and absorption. Influences of coolant temperature, piston stroke/speed, and volume change period on hydrate formation kinetics were investigated. Suggestions of reactor design improvement for future experimental study are also made

  12. Mental health differences between German gay and bisexual men and population-based controls.

    Science.gov (United States)

    Sattler, Frank A; Franke, Gabriele H; Christiansen, Hanna

    2017-07-21

    International studies have revealed that gay and bisexual men present more mental health problems than the general male population. Furthermore, there is evidence that minority stress predicts mental health problems in gay and bisexual men. The aim of the present study is to provide initial data on mental health differences in Germany and to analyze the effect of minority stress. Mental health data on n = 1903 German gay and bisexual men and n = 958 men from a population-based sample were assessed using a shortened version of the SCL-90-S. The mental health of the two samples was compared. Furthermore, a linear regression was conducted for the gay and bisexual sample: mental health was used as the criterion and minority stressors as predictors. As compared to our population sample, gay and bisexual men demonstrated more mental health problems with a moderate effect size. In the regression, minority stress predicted mental health problems in the gay and bisexual sample. We observed pronounced mental health differences between gay and bisexual men versus the population sample. These differences could be at least partly due to the minority stress gay and bisexual men face. Research should focus on how to reduce and cope with minority stress.

  13. Formation of submarine gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Soloviev, V.; Ginsburg, G.D. (Reserch Institute of Geology and Mineral Resources of the Ocean ' ' VNII Okeangeologia' ' , St. Petersburg (Russian Federation))

    1994-03-01

    Submarine gas hydrates have been discoverd in the course of deep-sea drilling (DSDP and ODP) and bottom sampling in many offshore regions. This paper reports on expeditions carried out in the Black, Caspian and Okhotsk Seas. Gas hydrate accumulations were discovered and investigated in all these areas. The data and an analysis of the results of the deep-sea drilling programme suggest that the infiltration of gas-bearing fluids is a necessary condition for gas hydrate accumulation. This is confirmed by geological observations at three scale levels. Firstly, hydrates in cores are usually associated with comparatively coarse-grained, permeable sediments as well as voids and fractures. Secondly, hydrate accumulations are controlled by permeable geological structures, i.e. faults, diapirs, mud volcanos as well as layered sequences. Thirdly, in the worldwide scale, hydrate accumulations are characteristic of continental slopes and rises and intra-continental seas where submarine seepages also are widespread. Both biogenic and catagenic gas may occur, and the gas sources may be located at various distances from the accumulation. Gas hydrates presumably originate from water-dissolved gas. The possibility of a transition from dissolved gas into hydrate is confirmed by experimental data. Shallow gas hydrate accumulations associated with gas-bearing fluid plumes are the most convenient features for the study of submarine hydrate formation in general. These accumulations are known from the Black, Caspian and Okhotsk Seas, the Gulf of Mexico and off northern California. (au) (24 refs.)

  14. Experiences of harassment, discrimination, and physical violence among young gay and bisexual men.

    Science.gov (United States)

    Huebner, David M; Rebchook, Gregory M; Kegeles, Susan M

    2004-07-01

    We examined the 6-month cumulative incidence of anti-gay harassment, discrimination, and violence among young gay/bisexual men and documented their associations with mental health. Gay/bisexual men from 3 cities in the southwestern United States completed self-administered questionnaires. Thirty-seven percent of men reported experiencing anti-gay verbal harassment in the previous 6 months; 11.2% reported discrimination, and 4.8% reported physical violence. Men were more likely to report these experiences if they were younger, were more open in disclosing their sexual orientation to others, and were HIV positive. Reports of mistreatment were associated with lower self-esteem and increased suicidal ideation. Absent policies preventing anti-gay mistreatment, empowerment and community-building programs are needed for young gay/bisexual men to both create safe social settings and help them cope with the psychological effects of these events.

  15. Broadband Seismic Studies at the Mallik Gas Hydrate Research Well

    Science.gov (United States)

    Sun, L. F.; Huang, J.; Lyons-Thomas, P.; Qian, W.; Milkereit, B.; Schmitt, D. R.

    2005-12-01

    The JAPEX/JNOC/GSC et al. Mallik 3L-38, 4L-38 and 5L-38 scientific wells were drilled in the MacKenzie Delta, NWT, Canada in early 2002 primarily for carrying out initial tests of the feasibility of producing methane gas from the large gas hydrate deposits there [1]. As part of this study, high resolution seismic profiles, a pseudo-3D single fold seismic volume and broadband (8~180Hz) multi-offset vertical seismic profiles (VSP) were acquired at the Mallik site. Here, we provide details on the acquisition program, present the results of the 2D field profile, and discuss the potential implications of these observations for the structure of the permafrost and gas hydrate zones. These zones have long been problematic in seismic imaging due to the lateral heterogeneities. Conventional seismic data processing usually assume a stratified, weak-contrast elastic earth model. However, in permafrost and gas hydrate zones this approximation often becomes invalid. This leads to seismic wave scattering caused by multi-scale perturbation of elastic properties. A 3D viscoelastic finite difference modeling algorithm was employed to simulate wave propagation in a medium with strong contrast. Parameters in this modeling analysis are based on the borehole geophysical log data. In addition, an uncorrelated Vibroseis VSP data set was studied to investigate frequency-dependent absorption and velocity dispersion. Our results indicate that scattering and velocity dispersion are important for a better understanding of attenuation mechanisms in heterogeneous permafrost and gas hydrate zones. [1] Dallimore, S.R., Collett, T.S., Uchida, T., and Weber, M., 2005, Overview of the science program for the Mallik 2002 Gas Hydrate Production Research Well Program; in Scientific Results from Mallik 2002 Gas Hydrate production Research Well Program, MacKenzie Delta, Northwest Territories, Canada, (ed.) S.R. Dallimore and T.S. Collett; Geological Survey of Canada, Bulletin 585, in press.

  16. Emo Gay Boys and Subculture: Postpunk Queer Youth and (Re)thinking Images of Masculinity

    Science.gov (United States)

    Peters, Brian M.

    2010-01-01

    This is an exploration of gay youth subculture and emo boys. The study is a mesh of findings and related theoretical understandings about gay emo subculture, masculinities, style, and alternative gay youth. This study looks at gay male teenagers who identify with emo, a movement that stems from music and aesthetics creating a particular visual for…

  17. Between Two Worlds: an Ethnographic Study of Gay Consumer Culture in Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Severino Joaquim Nunes Pereira

    2012-04-01

    Full Text Available It is not easy to study socially marginalized groups such as gays, ethnic minorities, and others. This is, however,an extremely relevant topic in the consumer behavior area since the status of members of a modern consumersociety is largely denied to stigmatized social groups (Barbosa, 2006. The objective of this work is to shed lighton how gay men in Rio de Janeiro use the discourse associated with their possessions to build and maintain thesymbolic and hierarchical boundaries between the gay and heterosexual worlds, as well as to investigate the roleconsumption plays in this boundary setting. An ethnographic observation of a group of gay men in Rio deJaneiro was conducted, along with 20 semi-structured interviews with openly gay men between 2005 and 2008.The results suggest that: (a the world culturally built by gays seems to be divided into a gay world and aheterosexual world, where the division between these two worlds not only happens in their minds, but also intheir possessions and purchasing decisions; (b the meaning of gay mens’ places of consumption range fromprofane to sacred along their lives; and (c in the gay world, the body is seen both as a cultural construction andas an asset.

  18. Hydrate thermal dissociation behavior and dissociation enthalpies in methane-carbon dioxide swapping process

    DEFF Research Database (Denmark)

    Mu, Liang; von Solms, Nicolas

    2018-01-01

    The swapping of methane with carbon dioxide in hydrate has been proposed as a potential strategy for geologic sequestration of carbon dioxide and production of methane from natural hydrate deposits. However, this strategy requires a better understanding of the thermodynamic characteristics of CH4...... and CO2 hydrate as well as (CH4 + CO2) or (CH4 + CO2 + N2) mixed hydrates (since (CO2 + N2) gas mixture is often used as the swapping gas), along with the thermal physics property changes during gas exchange. In this study, a high pressure micro-differential scanning calorimetry (HP μ-DSC) was performed...

  19. On the conditions of preparation of hydrated rare earth orthovanadates

    International Nuclear Information System (INIS)

    Nakhodnova, A.P.; Belousova, E.E.; Shuba, Yu.I.; Zaslavskij, L.V.

    1988-01-01

    The properties of Ln(NO 3 ) 3 -Na 3 VO 4 -H 2 O solution series, where Ln is Er, Ho, Eu are investigated by the methods of residual concentrations, conductometry and potentiometry. It is found that at equivalent ratios of the initial components LnVO 4 xmH 2 O hydrated orthovanadates are formed. Deviations towards excess of rare earths or vanadium result in contamination of the compounds by products of side reactions. According to the data on X-ray phase analysis, hydrated erbium, holmium, europium orthovanadates have the zirconium crystal structure typical for anhydrous compounds. It is shown that hydrate water, being a component of orthovanadates, can be referred to adsorbed and interlayer water

  20. Unsettled Relations: Schools, Gay Marriage, and Educating for Sexuality

    Science.gov (United States)

    Mayo, Cris

    2013-01-01

    In this article, Cris Mayo examines the relationship among anti-LGBTQ policies, gay marriage, and sexuality education. Her concern is that because gay marriage is insufficiently different from heterosexual marriage, adding it as an issue to curriculum or broader culture debate elides rather than addresses sexual difference. In other words,…

  1. Homecoming: the relevance of radical feminism for gay men.

    Science.gov (United States)

    Jensen, Robert

    2004-01-01

    Sexual politics in the gay male world would be enhanced by a serious engagement with radical feminist politics, particularly critiques of pornography and the sex industry. As the domination/subordination dynamic at the heart of patriarchy damages homosexual men, such engagement is crucial to the future of a gay movement.

  2. Becoming Gay Fathers through Transnational Commercial Surrogacy

    DEFF Research Database (Denmark)

    Petersen, Michael Nebeling

    2018-01-01

    Based on eight interviews with Danish gay male couples and one gayman, who had or were planning to become fathers through transnationalcommercial surrogacy, I examine the ways the men form familysubjectivities between traditional kinship patterns and fundamentally newforms of kinship and family....... Arguing that class, mobility, and privilegeshould also be understood as relational and negotiated positions, I showthat gay men engaged in surrogacy must be understood as more flexibleand differentiated. Second, I show how kinship as synonymous withbiogenetic relatedness is supplemented by notions...

  3. International Society of Nephrology-Hydration and Kidney Health Initiative - Expanding Research and Knowledge.

    Science.gov (United States)

    Moist, Louise M; Clark, William F; Segantini, Luca; Damster, Sandrine; Le Bellego, Laurent; Wong, Germaine; Tonelli, Marcello

    2016-01-01

    The purpose of this manuscript is to describe a collaborative research initiative to explore the role of hydration in kidney health. Our understanding of the effects of hydration in health and disease is surprisingly limited, particularly when we consider the vital role of hydration in basic human physiology. Recent initiatives and research outcomes have challenged the global medical community to expand our knowledge about hydration, including the differences between water, sugared beverages and other consumables. Identification of the potential mechanisms contributing to the benefits of hydration has stimulated the global nephrology community to advance research regarding hydration for kidney health. Hydration and kidney health has been a focus of research for several research centers with a rapidly expanding world literature and knowledge. The International Society of Nephrology has collaborated with Danone Nutricia Research to promote development of kidney research initiatives, which focus on the role of hydration in kidney health and the global translation of this new information. This initiative supports the use of existing data in different regions and countries to expand dialogue among experts in the field of hydration and health, and to increase scientific interaction and productivity with the ultimate goal of improving kidney health. © 2016 The Author(s) Published by S. Karger AG, Basel.

  4. Methods to determine hydration states of minerals and cement hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Baquerizo, Luis G., E-mail: luis.baquerizoibarra@holcim.com [Innovation, Holcim Technology Ltd., CH-5113 Holderbank (Switzerland); Matschei, Thomas [Innovation, Holcim Technology Ltd., CH-5113 Holderbank (Switzerland); Scrivener, Karen L. [Laboratory of Construction Materials, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Saeidpour, Mahsa; Thorell, Alva; Wadsö, Lars [Building Materials, Lund University, Box 124, 221 000 Lund (Sweden)

    2014-11-15

    This paper describes a novel approach to the quantitative investigation of the impact of varying relative humidity (RH) and temperature on the structure and thermodynamic properties of salts and crystalline cement hydrates in different hydration states (i.e. varying molar water contents). The multi-method approach developed here is capable of deriving physico-chemical boundary conditions and the thermodynamic properties of hydrated phases, many of which are currently missing from or insufficiently reported in the literature. As an example the approach was applied to monosulfoaluminate, a phase typically found in hydrated cement pastes. New data on the dehydration and rehydration of monosulfoaluminate are presented. Some of the methods used were validated with the system Na{sub 2}SO{sub 4}–H{sub 2}O and new data related to the absorption of water by anhydrous sodium sulfate are presented. The methodology and data reported here should permit better modeling of the volume stability of cementitious systems exposed to various different climatic conditions.

  5. Methods to determine hydration states of minerals and cement hydrates

    International Nuclear Information System (INIS)

    Baquerizo, Luis G.; Matschei, Thomas; Scrivener, Karen L.; Saeidpour, Mahsa; Thorell, Alva; Wadsö, Lars

    2014-01-01

    This paper describes a novel approach to the quantitative investigation of the impact of varying relative humidity (RH) and temperature on the structure and thermodynamic properties of salts and crystalline cement hydrates in different hydration states (i.e. varying molar water contents). The multi-method approach developed here is capable of deriving physico-chemical boundary conditions and the thermodynamic properties of hydrated phases, many of which are currently missing from or insufficiently reported in the literature. As an example the approach was applied to monosulfoaluminate, a phase typically found in hydrated cement pastes. New data on the dehydration and rehydration of monosulfoaluminate are presented. Some of the methods used were validated with the system Na 2 SO 4 –H 2 O and new data related to the absorption of water by anhydrous sodium sulfate are presented. The methodology and data reported here should permit better modeling of the volume stability of cementitious systems exposed to various different climatic conditions

  6. Enthalpy of dissociation and hydration number of methane hydrate from the Clapeyron equation

    International Nuclear Information System (INIS)

    Anderson, Graydon K.

    2004-01-01

    The enthalpies of the reactions in which methane hydrate is dissociated to methane vapor and either (1) water, or (2) ice are determined by a new analysis using the Clapeyron equation. The difference in enthalpies of the two reactions is used to infer the hydration number at the quadruple point where hydrate, ice, liquid water, and methane vapor coexist. By appropriate corrections, the hydration number at points removed from the quadruple point is also determined. The most important feature of the new analysis is the direct use of the Clapeyron equation. The method avoids the use of certain simplifying assumptions that have compromised the accuracy of previous analyses in which the Clausius-Clapeyron equation was used. The analysis takes into account the finite volumes of all phases, the non-ideality of the vapor phase, and the solubility of methane in water. The results show that the enthalpy of dissociation and hydration number are constant within experimental error over the entire (hydrate, liquid, vapor) coexistence region. The results are more accurate than but entirely consistent with almost all previous studies

  7. Paradoxes of an assimilation politics: media production of gay male belonging in the Canadian 'vital public' from the tainted blood scandal to the present.

    Science.gov (United States)

    Crath, Rory; Rangel, Cristian

    2017-07-01

    Canadian media discourses on gay men's sexuality and political inclusion serve as a rich site for understanding current tensions in debates on sexual citizenship under biopolitical regimes. This paper addresses how public health reporting in one health news media source, Canada's leading newspaper The Globe and Mail, discursively produced contiguous understandings of the moral, social and biological dimensions of gay male subjectivity and sexuality within the context of HIV risk discourses. Specifically, we critically examine the newspaper's coverage of what constitutes the public good when national blood supplies are at stake. Our analysis reveals a profound dichotomy in which gay men - as sexual subjects and subjects of rights - are recalibrated following the political and economic investments of bourgeoisie communities of interest. However encompassing the securing of legal social rights might be, gay men's sexuality is resistant to a reformatting under a heteronormative regulatory regime, as the social traumas caused by HIV continue to cast a shadow on sexual behaviours that purportedly risk leakage of contamination into the body politic.

  8. Development of an offshore gas field - investigation of hydrate and paraffin formation potential with regard to flow assurance; Entwicklung eines Offshore-Gasfeldes: Hydrat- und Paraffinuntersuchungen zur Sicherstellung der kontinuierlichen Produktion

    Energy Technology Data Exchange (ETDEWEB)

    Zettlitzer, M.; Busch, M. [RWE Dea AG, Wietze (Germany)

    2005-11-01

    During the production of offshore gas fields, raw gas from a number of production wells is usually led to a platform or - for reservoirs located close to shore - even transported as wet gas to an onshore gas treatment plant. The pipelines are located at the sea bottom, resulting in significant cooling of the raw gas with subsequent potential for the formation of hydrates and/or precipitation of paraffin on the pipeline walls. In order to safeguard continuous production, additional installations and/or dosage of chemicals would possibly be required. On the basis of gas and condensate samples from production tests, the formation potential for paraffins was experimentally investigated while the hydrate formation potential was assessed by simulations. The very small volume of condensate available (2-3 ml of each sample) formed a special challenge and limited the number of possible analytical investigations. Nevertheless, wax appearance temperature of five condensates under investigation could successfully be determined by a combination of gas-chromatographic and rheological measurements. Two of the three gas-bearing layers turned out to produce dry gas so that paraffin problems can be excluded. However, according to the simulations, hydrate formation at temperatures {<=}+20 C has to be expected under the formation pressure of about 200 bars. The third layer contains a gas condensate, causing paraffin precipitation at {<=}0 C and forming hydrate in a temperature range similar to that of the other two sands. Hence, precautions have to taken to prevent hydrate formation in all field lines containing wet gas. Furthermore, the paraffin precipitation potential has to be taken into account in the subsequent low-temperature gas-treatment plant. (orig.)

  9. Experimental setting for assessing mechanical strength of gas hydrate pellet

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, S.J.; Choi, J.H.; Koh, B.H. [Dongguk Univ., Phil-dong, Chung-gu, Seoul (Korea, Republic of). Dept. of Mechanical Engineering

    2008-07-01

    Due to the constant increase in global demand for clean energy, natural gas production from stranded medium and small size gas wells has drawn significant interest. Because the ocean transport of natural gas in the form of solid hydrate pellets (NGHP) has been estimated to be economically feasible, several efforts have been made to develop a total NGHP ocean transport chain. The investigation of mechanical strength of solid-form hydrate pellet has been an important task in fully exploiting the benefit of gas hydrate in the perspective of mass transportation and storage. This paper provided the results of a preliminary study regarding the assessment of mechanical properties of the gas hydrate pellet. The preliminary study suggested some of the key issues regarding formation and strength of gas hydrate pellets. Instead of utilizing the gas hydrate pellet, the study focused on a preliminary test setup for developing the ice pellet which was readily applied to the gas hydrate pellet in the future. The paper described the pelletization of ice powder as well as the experimental setup. Several photographs were illustrated, including samples of ice pellets; compression test for ice pellet using air press and load cell; and the initiation of crack in the cross section of an ice pellet. It was found that mechanical strength, especially, compression strength was not significantly affected by different level of press-forming force up to a certain level. 4 refs., 1 tab., 4 figs.

  10. Fire extinction utilizing carbon dioxide hydrate

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, T.; Aida, E.; Yokomori, T.; Ohmura, R.; Ueda, T. [Keio Univ., Hiyoshi, Kohoku-ku, Yokohama (Japan)

    2008-07-01

    Clathrate hydrates formed with nonflammable gases may be suitable for use as fire extinguishing agents because dissociation of the hydrates results in the temperature decrease in the combustion field and the nonflammable gases released from the dissociated hydrates prevent the supply of the oxygen to the combustion field. This paper discussed experiments in which ordinary ice and dry ice were used to evaluate the performance of CO{sub 2} hydrate as a fire extinguishing agent. The paper described the apparatus and procedure for the preparation of CO{sub 2} hydrate crystals. A schematic of the reactor to form CO{sub 2} hydrate and a photograph of CO{sub 2} hydrate crystal formed in the study were also presented. Other illustrations, photographs, and tables that were presented included a schematic diagram of the experimental apparatus used for the flame extinction experiments; a photograph of CO{sub 2} hydrate powder; sequential video graphs of the flame extinction by the supply of CO{sub 2} hydrate crystals to the methanol pool flame and the relevant illustration; and heat of CO{sub 2} hydrate dissociation, water vaporization and sublimation of dry ice. It was concluded that the critical mass of the CO{sub 2} hydrate required to extinguish a flame was much less than that of ordinary ice, indicating the superiority of CO{sub 2} hydrate to the ice. In addition, the experiments also revealed that the size of the CO{sub 2} hydrate particles had a significant effect on the performance of flame extinction. 5 refs., 2 tabs., 7 figs.

  11. Cultural Development Strategies and Urban Gay Tourism Revitalization

    Directory of Open Access Journals (Sweden)

    Jose M Prat Forga

    2015-12-01

    Full Text Available Municipal governments increasingly turn to cultural and leisure activities to promote and revitalize their cities. This study analysed the development of gay tourism in Barcelona (Spain by means of music festivals. While a significant body of literature has examined revitalization strategies that focus primarily around entertainment and commerce, this paper focuses on strategies in the development of cultural and leisure activities around this specific tourism population. It presents findings from a local survey distributed to key stakeholders in the promotion and development of this tourism (local agents and gay tourists. The survey data indicate that although most agents are guided by a varied set of goals, marketing objectives (“image city” and “brand city” guide the development and support of urban gay tourism in Barcelona.

  12. The Gay Panic Defense: Legal Defense Strategy or Reinforcement of Homophobia in Court?

    Science.gov (United States)

    Tomei, Jenna; Cramer, Robert J; Boccaccini, Marcus T; Panza, Nancy Ryba

    2017-06-01

    Gay panic refers to a heterosexual man violently responding to unwanted sexual advances from a gay man. In court, the defendant may argue he was provoked or temporarily insane. This study utilized 352 jury-eligible citizens to assess differences across mediums of gay panic. Participants were asked to read vignettes depicting a control, gay panic as provocation, or gay panic as insanity condition and provide verdicts and ratings of blame and responsibility. Participants also completed measures assessing political orientation and homonegativity. Data were analyzed via a MANCOVA, a chi-square goodness-of-fit test, and general linear modeling. Verdicts, victim blame, and ratings of responsibility differed across vignette conditions, with an observed leniency effect when gay panic was claimed in either context. Homonegativity also exacerbated patterns of prodefendant views, as participants higher in homonegativity assigned higher victim blame, lower defendant responsibility, and more lenient verdicts in the gay panic conditions. The effect of political orientation was nuanced, as only republicans in the provocation condition followed the anticipated pattern in rendering more lenient verdicts. Results provide additional support for the notion gay panic defenses may be, in part, fueled by political beliefs and prejudicial beliefs against persons of sexual minority status. Drawing from a justification-suppression model, it may be that in cases of gay panic, a context is created in which prejudiced ideologies can be openly expressed via leniency on the defendant. Implications may be relevant to future criminal law policies and practices, particularly advocacy and policy efforts, judicial training, and trial consultation to attorneys for juror selection and development of trial strategy.

  13. Waters of Hydration of Cupric Hydrates: A Comparison between Heating and Absorbance Methods

    Science.gov (United States)

    Barlag, Rebecca; Nyasulu, Frazier

    2011-01-01

    The empirical formulas of four cupric hydrates are determined by measuring the absorbance in aqueous solution. The Beer-Lambert Law is verified by constructing a calibration curve of absorbance versus known Cu[superscript 2+](aq) concentration. A solution of the unknown hydrate is prepared by using 0.2-0.3 g of hydrate, and water is added such…

  14. Guidelines for Counseling Gay Males With Low Self-Esteem.

    Science.gov (United States)

    Nagorski, Alec P.

    The purpose of this study was to gain an understanding of the relationship between a gay male's low self-esteem and environmental oppression, thereby establishing guidelines for the counselor in directing the client toward a more positive gay identity. This document is divided into the following sections: (1) Initial Interview; (2) Theory of…

  15. Disclosure, discrimination and desire: experiences of Black and South Asian gay men in Britain.

    Science.gov (United States)

    McKeown, Eamonn; Nelson, Simon; Anderson, Jane; Low, Nicola; Elford, Jonathan

    2010-10-01

    Using findings from a qualitative investigation based on in-depth email interviews with 47 Black and South Asian gay men in Britain, this paper explores the cross-cutting identities and discourses in relation to being both gay and from an ethnic minority background. Taking an intersectional approach, detailed accounts of identity negotiation, cultural pressures, experiences of discrimination and exclusion and the relationship between minority ethnic gay men and mainstream White gay culture are presented and explored. The major findings common to both groups were: cultural barriers limiting disclosure of sexuality to family and wider social networks; experiences of discrimination by White gay men that included exclusion as well as objectification; a lack of positive gay role models and imagery relating to men from minority ethnic backgrounds. Among South Asian gay men, a major theme was regret at being unable to fulfil family expectations regarding marriage and children, while among Black gay men, there was a strong belief that same-sex behaviour subverted cultural notions related to how masculinity is configured. The paper concludes by highlighting the importance of social location, particularly education and income, when examining the intersection of ethnicity and sexuality in future research.

  16. Role Portrayal of Gay Men in Print Advertisements: A Study on US Market

    OpenAIRE

    satyaprakash, shilpa

    2010-01-01

    This dissertation research is aimed at analyzing the gay roles portrayal in print advertisements by the advertisers. In order to conduct this study, the researcher had selected sample of gay advertisements from the leading US gay magazine and the mainstream magazine. The researcher also developed a coding sheet for the purpose of this analysis. The coding sheet was developed on the basis of various aspects which would enable to find out the various roles that could be portrayed by the gay men...

  17. GAY RELATIONSHIPS AS ALTERNATIVE FORMS OF FAMILY-MARRIAGE LIFE

    Directory of Open Access Journals (Sweden)

    Ewa Perlińska

    2006-01-01

    Full Text Available My research and deliberation made in this study show that homosexuality is only one of the signs of human diversity - one from innumerable number of personality features. Therefore, one cannot talk about "gay identity", "homosexual personality", because, as far as I am concerned, it doesn't exist. Artificially generted gay population is only a group of peple being much different from one another and having only one common feature - their sexual orientation. Besides they differ from one another as much as one man from another. Gay relationships take on countless forms, but all of them, as the results of my research indicate, fulfil the majority of family in traditional point of view functions. The deliberation points out at one more conclusion - one cannot examine gay relationships as a separate model of family-marriage life. It should be forgotten about their different psyhosexual orientation and treat their trlationships, together with other interpersonal relationships, equally. Only from such position one can discern in their specific alternative models of family-marriage life.

  18. An innovative approach to enhance methane hydrate formation kinetics with leucine for energy storage application

    International Nuclear Information System (INIS)

    Veluswamy, Hari Prakash; Kumar, Asheesh; Kumar, Rajnish; Linga, Praveen

    2017-01-01

    Highlights: • Innovative combinatorial hybrid approach to reduce nucleation stochasticity and enhance hydrate growth. • Methane hydrate growth curves are similar in UTR and STR configurations in presence of leucine. • Amalgamation of stirred (STR) and unstirred (UTR) configuration is demonstrated. • Reliable method for scale up and commercial production of Solidified Natural Gas (SNG). - Abstract: Natural gas storage in clathrate hydrates or solidified natural gas (SNG) offers the safest, cleanest and the most compact mode of storage aided by the relative ease in natural gas (NG) recovery with minimal cost compared to known conventional methods of NG storage. The stochastic nature of hydrate nucleation and the slow kinetics of hydrate growth are major challenges that needs to be addressed on the SNG production side. A deterministic and fast nucleation coupled with rapid crystallization kinetics would empower this beneficial technology for commercial application. We propose a hybrid combinatorial approach of methane hydrate formation utilizing the beneficial aspect of environmentally benign amino acid (leucine) as a kinetic promoter by combining stirred and unstirred reactor operation. This hybrid approach is simple, can easily be implemented and scaled-up to develop an economical SNG technology for efficient storage of natural gas on a large scale. Added benefits include the minimal energy requirement during hydrate growth resulting in overall cost reduction for SNG technology.

  19. Clubbing masculinities: gender shifts in gay men's dance floor choreographies.

    Science.gov (United States)

    Peterson, Grant Tyler

    2011-01-01

    This article adopts an interdisciplinary approach to understanding the intersections of gender, sexuality, and dance. It examines the expressions of sexuality among gay males through culturally popular forms of club dancing. Drawing on political and musical history, I outline an account of how gay men's gendered choreographies changed throughout the 1970s, 80s, and 90s. Through a notion of "technologies of the body," I situate these developments in relation to cultural levels of homophobia, exploring how masculine expressions are entangled with and regulated by musical structures. My driving hypothesis is that as perceptions of cultural homophobia decrease, popular choreographies of gay men's dance have become more feminine in expression. Exploring this idea in the context of the first decade of the new millennium, I present a case study of TigerHeat, one of the largest weekly gay dance club events in the United States.

  20. Submarine methane hydrates - Potential fuel resource of the 21st century

    Digital Repository Service at National Institute of Oceanography (India)

    Desa, E.

    of these countries to initiate harvesting methane hydrates as soon as scientists and technologists come forward with dependable, safe and cost effective mechanisms to explore and exploit this resource. Technological factors : Lack of suitable production technology... reduction in deep-water development costs. All these are positive factors for hydrate exploration and development. Much of the engineering required to exploit these deposits can be achieved by suitably adopting proven technology currently used...

  1. The Potential Socio-economic Impacts of Gas Hydrate Exploitation

    Science.gov (United States)

    Riley, David; Schaafsma, Marije; Marin-Moreno, Héctor; Minshull, Tim A.

    2017-04-01

    Gas hydrate has garnered significant interest as a possible clean fossil fuel resource, especially in countries with limited energy supplies. Whilst the sector is still in its infancy, there has been escalating development towards commercial production. To the best of our knowledge it appears that, despite its potential, existing analyses of the social and economic impacts of hydrate exploitation have been very limited. Before any viable commercial production commences, the potential impacts across society must be considered. It is likely that such impact assessments will become a legislative requirement for hydrate exploitation, similar to their requirement in conventional oil and gas projects. Social impact analysis should guide hydrate development to have the highest possible net benefits to the human and natural environment. Without active commercial hydrate operations, potential socio-economic impacts can only be inferred from other fossil fuel resource focused communities, including those directly or indirectly affected by the oil and gas industry either in the vicinity of the well or further afield. This review attempts to highlight potential impacts by synthesising current literature, focusing on social impacts at the extraction stage of operation, over time. Using a DPSIR (Driving forces; Pressures; States; Impacts; Responses) framework, we focus on impacts upon: health and wellbeing, land use and access, services and infrastructure, population, employment opportunities, income and lifestyles. Human populations directly or indirectly related with fossil fuel extraction activities often show boom and bust dynamics, and so any impacts may be finite or change temporally. Therefore potential impacts have to be reassessed throughout the lifetime of the exploitation. Our review shows there are a wide range of possible positive and negative socio-economic impacts from hydrate development. Exploitation can bring jobs and infrastructure to remote areas, although

  2. Maximum Recoverable Gas from Hydrate Bearing Sediments by Depressurization

    KAUST Repository

    Terzariol, Marco; Goldsztein, G.; Santamarina, Carlos

    2017-01-01

    financial analyses; results highlight the need for innovative production strategies in order to make hydrate accumulations an economically-viable energy resource. Horizontal directional drilling and multi-wellpoint seafloor dewatering installations may lead

  3. Proceedings of the 6. international conference on gas hydrates : ICGH 2008

    Energy Technology Data Exchange (ETDEWEB)

    Englezos, P. (ed.) [British Columbia Univ., Vancouver, BC (Canada); Ripmeester, J. (ed.) [National Research Council of Canada, Ottawa, ON (Canada); Dallimore, S.R. [Natural Resources Canada, Ottawa, ON (Canada). Geological Survey of Canada; Servio, P. [McGill Univ., Montreal, PQ (Canada). Dept. of Chemical Engineering; Austvik, T. [Statoil, Trondheim (Norway); Collett, T.S. [United States Geological Survey, Denver, CO (United States); Mehta, A. [Shell E and P Asia Pacific, Sarawak (Malaysia); Paull, C.K. [Monterey Bay Aquarium Research Inst., CA (United States); Sloan, E.D.Jr. [Colorado School of Mines, Golden, CO (United States); Uchida, T. [Hokkaido Univ., Sapporo (Japan)] (comps.)

    2008-07-01

    This international conference provided a forum to highlight gas hydrate research that is underway at academic institutions as well as government and industrial laboratories around the world. The gas or clathrate hydrate research community includes chemical, petroleum and mechanical engineers, geologists, geophysicists, marine biologists, chemists and physicists. The conference was attended by more than 500 delegates who presented their professional knowledge in all areas of the gas hydrates field, emphasizing new aspects. The topics of discussion included resource delineation, reservoir simulation modeling and production technology. Environmental considerations involving natural gas hydrates and global climate change were also highlighted along with carbon dioxide disposal in aquifers and deep oceans. Issues facing oil and gas operations were also discussed, with reference to flow assurance in pipelines, safety issues, permafrost and marine geohazards. Novel technologies involving hydrogen storage, carbon dioxide capture and sequestration were also highlighted along with basic science and engineering aspects of gas hydrate systems. All 417 presentations from the conference have been catalogued separately for inclusion in this database. refs., tabs., figs.

  4. Proceedings of the 6. international conference on gas hydrates : ICGH 2008

    International Nuclear Information System (INIS)

    Englezos, P.; Ripmeester, J.; Dallimore, S.R.; Collett, T.S.; Mehta, A.; Paull, C.K.; Sloan, E.D.Jr.; Uchida, T.

    2008-01-01

    This international conference provided a forum to highlight gas hydrate research that is underway at academic institutions as well as government and industrial laboratories around the world. The gas or clathrate hydrate research community includes chemical, petroleum and mechanical engineers, geologists, geophysicists, marine biologists, chemists and physicists. The conference was attended by more than 500 delegates who presented their professional knowledge in all areas of the gas hydrates field, emphasizing new aspects. The topics of discussion included resource delineation, reservoir simulation modeling and production technology. Environmental considerations involving natural gas hydrates and global climate change were also highlighted along with carbon dioxide disposal in aquifers and deep oceans. Issues facing oil and gas operations were also discussed, with reference to flow assurance in pipelines, safety issues, permafrost and marine geohazards. Novel technologies involving hydrogen storage, carbon dioxide capture and sequestration were also highlighted along with basic science and engineering aspects of gas hydrate systems. All 417 presentations from the conference have been catalogued separately for inclusion in this database. refs., tabs., figs

  5. Indian continental margin gas hydrate prospects : results of the Indian National Gas Hydrate Program (NGHP) expedition 01

    Energy Technology Data Exchange (ETDEWEB)

    Collett, T [United States Geological Survey, Denver, CO (United States); Riedel, M. [McGill Univ., Montreal, PQ (Canada). Dept. of Earth and Planetary Sciences; Cochran, J.R. [Columbia Univ., Palisades, NY (United States). Lamont Doherty Earth Observatory; Boswell, R. [United States Dept. of Energy, Morgantown, WV (United States). National Energy Technology Lab; Kumar, P. [Pushpendra Kumar Oil and Natural Gas Corp. Ltd., Mumbai (India). Inst. of Engineering and Ocean Technology; Sathe, A.V. [Oil and Natural Gas Corp. Ltd., Uttaranchal (India). KDM Inst. of Petroleum Exploration

    2008-07-01

    The geologic occurrence of gas hydrate deposits along the continental margins of India were investigated in the first expedition of the Indian National Gas Hydrate Program (NGHP). The objective was to determine the regional context and characteristics of the gas hydrate deposits through scientific ocean drilling, logging, and analytical activities. A research drill ship was the platform for the drilling operation. The geological and geophysical studies revealed 2 geologically distinct areas with inferred gas hydrate occurrences, notably the passive continental margins of the Indian Peninsula and along the Andaman convergent margin. The NGHP Expedition 01 focused on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these 2 diverse settings. The study established the presence of gas hydrates in Krishna-Godavari, Mahanadi and Andaman basins. Site 10 in the Krishna-Godavari Basin was discovered to be the one of the richest gas hydrate accumulations yet documented, while site 17 in the Andaman Sea had the thickest and deepest gas hydrate stability zone yet known. The existence of a fully-developed gas hydrate system in the Mahanadi Basin was also discovered. Most of the gas hydrate occurrences discovered during this expedition appeared to contain mostly methane which was generated by microbial processes. However, there was also evidence of a thermal origin for a portion of the gas within the hydrates of the Mahanadi Basin and the Andaman offshore area. Gas hydrate in the Krishna-Godavari Basin appeared to be closely associated with large scale structural features, in which the flux of gas through local fracture systems, generated by the regional stress regime, controlled the occurrence of gas hydrate. 3 refs., 1 tab., 2 figs.

  6. GAS METHANE HYDRATES-RESEARCH STATUS, ANNOTATED BIBLIOGRAPHY, AND ENERGY IMPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    James Sorensen; Jaroslav Solc; Bethany Bolles

    2000-07-01

    The objective of this task as originally conceived was to compile an assessment of methane hydrate deposits in Alaska from available sources and to make a very preliminary evaluation of the technical and economic feasibility of producing methane from these deposits for remote power generation. Gas hydrates have recently become a target of increased scientific investigation both from the standpoint of their resource potential to the natural gas and oil industries and of their positive and negative implications for the global environment After we performed an extensive literature review and consulted with representatives of the U.S. Geological Survey (USGS), Canadian Geological Survey, and several oil companies, it became evident that, at the current stage of gas hydrate research, the available information on methane hydrates in Alaska does not provide sufficient grounds for reaching conclusions concerning their use for energy production. Hence, the original goals of this task could not be met, and the focus was changed to the compilation and review of published documents to serve as a baseline for possible future research at the Energy & Environmental Research Center (EERC). An extensive annotated bibliography of gas hydrate publications has been completed. The EERC will reassess its future research opportunities on methane hydrates to determine where significant initial contributions could be made within the scope of limited available resources.

  7. Hydration and chemical ingredients in sport drinks: food safety in the European context.

    Science.gov (United States)

    Urdampilleta, Aritz; Gómez-Zorita, Saioa; Soriano, José M; Martínez-Sanz, José M; Medina, Sonia; Gil-Izquierdo, Angel

    2015-05-01

    Before, during and after physical activity, hydration is a limiting factor in athletic performance. Therefore, adequate hydration provides benefits for health and performance of athletes. Besides, hydration is associated to the intake of carbohydrates, protein, sodium, caffeine and other substances by different dietary aids, during the training and/or competition by athletes. These requirements have led to the development of different products by the food industry, to cover the nutritional needs of athletes. Currently in the European context, the legal framework for the development of products, substances and health claims concerning to sport products is incomplete and scarce. Under these conditions, there are many products with different ingredients out of European Food Safety Authority (EFSA) control where claims are wrong due to no robust scientific evidence and it can be dangerous for the health. Further scientific evidence should be constructed by new clinical trials in order to assist to the Experts Commitees at EFSA for obtaining robust scientific opinions concerning to the functional foods and the individual ingredients for sport population. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  8. On the conditions of preparation of hydrated rare earth orthovanadates

    Energy Technology Data Exchange (ETDEWEB)

    Nakhodnova, A P; Belousova, E E; Shuba, Yu I; Zaslavskij, L V

    1988-10-01

    The properties of Ln(NO/sub 3/)/sub 3/-Na/sub 3/VO/sub 4/-H/sub 2/O solution series, where Ln is Er, Ho, Eu are investigated by the methods of residual concentrations, conductometry and potentiometry. It is found that at equivalent ratios of the initial components LnVO/sub 4/xmH/sub 2/O hydrated orthovanadates are formed. Deviations towards excess of rare earths or vanadium result in contamination of the compounds by products of side reactions. According to the data on X-ray phase analysis, hydrated erbium, holmium, europium orthovanadates have the zirconium crystal structure typical for anhydrous compounds. It is shown that hydrate water, being a component of orthovanadates, can be referred to adsorbed and interlayer water.

  9. HYDRATION AND PROPERTIES OF BLENDED CEMENT SYSTEMS INCORPORATING INDUSTRIAL WASTES

    Directory of Open Access Journals (Sweden)

    Heikal M.

    2013-06-01

    Full Text Available This paper aims to study the characteristics of ternary blended system, namely granulated blast-furnace slag (WCS, from iron steel company and Homra (GCB from Misr Brick (Helwan, Egypt and silica fume (SF at 30 mass % pozzolanas and 70 mass % OPC. The required water of standard consistency and setting times were measured as well as physico-chemical and mechanical characteristics of the hardened cement pastes were investigated. Some selected cement pastes were tested by TGA, DTA and FT-IR techniques to investigate the variation of hydrated products of blended cements. The pozzolanic activity of SF is higher than GCB and WCS. The higher activity of SF is mainly due to its higher surface area than the other two pozzolanic materials. On the other side, GCB is more pozzolanic than WCS due to GCB containing crystalline silica quartz in addition to an amorphous phase. The silica quartz acts as nucleating agents which accelerate the rate of hydration in addition to its amorphous phase, which can react with liberating Ca(OH2 forming additional hydration products.

  10. In situ monitoring of the hydration process of K-PS geopolymer cement with ESEM

    International Nuclear Information System (INIS)

    Sun Wei; Zhang Yunsheng; Lin Wei; Liu Zhiyong

    2004-01-01

    Environmental scanning electron microscope (ESEM) was used to in situ quantitatively study the hydration process of K-PS geopolymer cement under an 80% RH environment. An energy dispersion X-ray analysis (EDXA) was also employed to distinguish the chemical composition of hydration product. The ESEM micrographs showed that metakaolin particles pack loosely at 10 min after mixing, resulting in the existence of many large voids. As hydration proceeds, a lot of gels were seen and gradually precipitated on the surfaces of these particles. At later stage, these particles were wrapped by thick gel layers and their interspaces were almost completely filled. The corresponding EDXA results illustrated that the molar ratios of K/Al increase while Si/Al decrease with the development of hydration. As a result, the molar ratios of K/Al and Si/Al of hydration products at an age of 4 h amounted to 0.99 and 1.49, respectively, which were close to the theoretical values (K/Al=1.0, Si/Al=1.0 for K-PS geopolymer cement paste). In addition, well-developed crystals could not been found at any ages; instead, spongelike amorphous gels were always been observed

  11. 'Kids are just cruel anyway': lesbian and gay parents' talk about homophobic bullying.

    Science.gov (United States)

    Clarke, Victoria; Kitzinger, Celia; Potter, Jonathan

    2004-12-01

    Psychologists recognize homophobic bullying as a serious problem for young lesbians and gay men; however, when it comes to children in lesbian and gay households the issue is not so clear cut. Some psychologists sympathetic to lesbian and gay parenting regard it as a problem, but most do not. Despite this, the inevitability and severe psychological consequences of homophobic bullying is a prevalent theme in discussions of lesbian and gay parenting in contexts ranging from custody cases to television talk shows, and is used to implicate lesbians and gay men as unfit to parent. This is the broader context in which lesbian and gay parents discuss their children's experiences of bullying. In this study, we provide a discursive psychological analysis of six lesbian and gay parents' accounts of bullying. We argue that these accounts are discursively and rhetorically designed to deal with a heterosexist social/political context. Lesbian and gay parents face a dilemma of stake and accountability: reports of no bullying risk being heard as implausible given the prevalence of the bullying theme; at the same time, reports of bullying are equally if not more risky, raising the possibility of charges of bad parenting. We explore the detail of the parents' accounts of bullying to illustrate how they are designed to negotiate this web of accountability, and we argue for the importance for critical social psychology of analysing the talk of socially/politically marginalized groups.

  12. Attitudes toward Lesbians and Gays among American and Dutch Adolescents

    Science.gov (United States)

    Collier, Kate L.; Horn, Stacey S.; Bos, Henny M. W.; Sandfort, Theo G. M.

    2014-01-01

    Attitudes toward lesbians and gays vary across national populations, and previous research has found relatively more accepting attitudes in the Netherlands as compared to the U.S. In this study, we compared beliefs about and attitudes toward lesbians and gays in samples of Dutch and American heterosexual adolescents, utilizing survey data from 1,080 American adolescents (mean age = 15.86 years) attending two schools and from 1,391 Dutch adolescents (mean age = 16.27 years) attending eight schools. Findings indicated the Dutch participants were more tolerant of lesbians and gays, after adjusting for the gender, age, and racial/ethnic minority status of the participants. However, between-country differences were attenuated by accounting for the beliefs about lesbians and gays that participants used to justify their attitudes. American participants were more likely to justify their attitudes using beliefs related to social norms and religious opposition, while the Dutch participants were more likely to justify their attitudes using beliefs related to individual rights and the biological/genetic basis of homosexuality. The results suggest that the relative importance of particular beliefs about lesbians and gays to attitudes at the group level may be context-dependent but also that certain beliefs are salient to attitudes across national contexts. PMID:24512056

  13. El porno gay hecho en México

    OpenAIRE

    Salinas Hernández, Héctor Miguel

    2011-01-01

    El presente trabajo propone presentar un panorama sobre la pornografía hecha en México por y para varones gay, en el ámbito del video y del cine. Arranca con la hipótesis de que la posibilidad de creación en México de porno exclusivo para varones gay se inserta en la visibilidad adquirida por el Movimiento de Disidencia Sexual a nivel mundial, facilitado por el mercado como elemento preponderante en la globalización. El documento presenta algunas aproximaciones teóricas a la pornografía y sus...

  14. Family support and acceptance, gay male identity formation, and psychological adjustment: a path model.

    Science.gov (United States)

    Elizur, Y; Ziv, M

    2001-01-01

    While heterosexist family undermining has been demonstrated to be a developmental risk factor in the life of persons with same-gender orientation, the issue of protective family factors is both controversial and relatively neglected. In this study of Israeli gay males (N = 114), we focused on the interrelations of family support, family acceptance and family knowledge of gay orientation, and gay male identity formation, and their effects on mental health and self-esteem. A path model was proposed based on the hypotheses that family support, family acceptance, family knowledge, and gay identity formation have an impact on psychological adjustment, and that family support has an effect on gay identity formation that is mediated by family acceptance. The assessment of gay identity formation was based on an established stage model that was streamlined for cross-cultural practice by defining three basic processes of same-gender identity formation: self-definition, self-acceptance, and disclosure (Elizur & Mintzer, 2001). The testing of our conceptual path model demonstrated an excellent fit with the data. An alternative model that hypothesized effects of gay male identity on family acceptance and family knowledge did not fit the data. Interpreting these results, we propose that the main effect of family support/acceptance on gay identity is related to the process of disclosure, and that both general family support and family acceptance of same-gender orientation play a significant role in the psychological adjustment of gay men.

  15. Concerns about aging and caregiving among middle-aged and older lesbian and gay adults.

    Science.gov (United States)

    Czaja, Sara J; Sabbag, Samir; Lee, Chin Chin; Schulz, Richard; Lang, Samantha; Vlahovic, Tatiana; Jaret, Adrienne; Thurston, Catherine

    2016-11-01

    Despite the increasing number of lesbian and gay older adults, research geared towards health and well-being of this population is limited. Many lesbian and gay seniors experience health disparities and are at risk for poor health outcomes. The aims of this study were to gather in-depth information on the concerns of lesbian and gay elders with respect to aging and care needs. The sample included 124 gay men and lesbian women aged 50+ years. Data were gathered via focus groups and questionnaires. The focus groups addressed: (1) concerns about aging in the LGBT community, (2) barriers to needed support and services, (3) concerns about caregiving and (4) needed programs for lesbian and gay seniors. Concerns expressed about aging included: lack of financial security, lack of family or social support, fears about the lack of someone to provide needed care, and discrimination in healthcare or service communities. Participants also indicated concerns about being alone and vulnerable and a need for resources and support programs, specifically for lesbian and gay older adults and for lesbian and gay caregivers. These findings suggest needed areas of support and programs for older gay men and lesbian women. They also suggest that healthcare professionals might need more training regarding the particular needs and concerns of this community.

  16. Characterisation of products of tricalcium silicate hydration in the presence of heavy metals

    International Nuclear Information System (INIS)

    Chen, Q.Y.; Hills, C.D.; Tyrer, M.; Slipper, I.; Shen, H.G.; Brough, A.

    2007-01-01

    The hydration of tricalcium silicate (C 3 S) in the presence of heavy metal is very important to cement-based solidification/stabilisation (s/s) of waste. In this work, tricalcium silicate pastes and aqueous suspensions doped with nitrate salts of Zn 2+ , Pb 2+ , Cu 2+ and Cr 3+ were examined at different ages by X-ray powder diffraction (XRD), thermal analysis (DTA/TG) and 29 Si solid-state magic angle spinning/nuclear magnetic resonance (MAS/NMR). It was found that heavy metal doping accelerated C 3 S hydration, even though Zn 2+ doping exhibited a severe retardation effect at an early period of time of C 3 S hydration. Heavy metals retarded the precipitation of portlandite due to the reduction of pH resulted from the hydrolysis of heavy metal ions during C 3 S hydration. The contents of portlandite in the control, Cr 3+ -doped, Cu 2+ -doped, Pb 2+ -doped and Zn 2+ -doped C 3 S pastes aged 28 days were 16.7, 5.5, 5.5, 5.5, and 2 Cr(OH) 7 .3H 2 O, Ca 2 (OH) 4 4Cu(OH) 2 .2H 2 O and CaZn 2 (OH) 6 .2H 2 O). These compounds were identified as crystalline phases in heavy metal doping C 3 S suspensions and amorphous phases in heavy metal doping C 3 S pastes. 29 Si NMR data confirmed that heavy metals promoted the polymerisation of C-S-H gel in 1-year-old of C 3 S pastes. The average numbers of Si in C-S-H gel for the Zn 2+ -doped, Cu 2+ -doped, Cr 3+ -doped, control, and Pb 2+ -doped C 3 S pastes were 5.86, 5.11, 3.66, 3.62, and 3.52. And the corresponding Ca/Si ratios were 1.36, 1.41, 1.56, 1.57 and 1.56, respectively. This study also revealed that the presence of heavy metal facilitated the formation of calcium carbonate during C 3 S hydration process in the presence of carbon dioxide

  17. Occurrence of gas hydrate in Oligocene Frio sand: Alaminos Canyon Block 818: Northern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Boswell, R.D.; Shelander, D.; Lee, M.; Latham, T.; Collett, T.; Guerin, G.; Moridis, G.; Reagan, M.; Goldberg, D.

    2009-07-15

    A unique set of high-quality downhole shallow subsurface well log data combined with industry standard 3D seismic data from the Alaminos Canyon area has enabled the first detailed description of a concentrated gas hydrate accumulation within sand in the Gulf of Mexico. The gas hydrate occurs within very fine grained, immature volcaniclastic sands of the Oligocene Frio sand. Analysis of well data acquired from the Alaminos Canyon Block 818 No.1 ('Tigershark') well shows a total gas hydrate occurrence 13 m thick, with inferred gas hydrate saturation as high as 80% of sediment pore space. Average porosity in the reservoir is estimated from log data at approximately 42%. Permeability in the absence of gas hydrates, as revealed from the analysis of core samples retrieved from the well, ranges from 600 to 1500 millidarcies. The 3-D seismic data reveals a strong reflector consistent with significant increase in acoustic velocities that correlates with the top of the gas-hydrate-bearing sand. This reflector extends across an area of approximately 0.8 km{sup 2} and delineates the minimal probable extent of the gas hydrate accumulation. The base of the inferred gas-hydrate zone also correlates well with a very strong seismic reflector that indicates transition into units of significantly reduced acoustic velocity. Seismic inversion analyses indicate uniformly high gas-hydrate saturations throughout the region where the Frio sand exists within the gas hydrate stability zone. Numerical modeling of the potential production of natural gas from the interpreted accumulation indicates serious challenges for depressurization-based production in settings with strong potential pressure support from extensive underlying aquifers.

  18. Another issue comes out: gay rights policy voting in recent U.S. presidential elections.

    Science.gov (United States)

    Rhodebeck, Laurie A

    2015-01-01

    Drawing from the theory of policy voting, this study examines the impact of opinions about gay rights on voting for presidential candidates. Qualitative analysis of the major party platforms and candidate campaign rhetoric from the six presidential elections held between 1988 and 2008 indicates that Democratic and Republican presidential candidates began openly expressing opposing positions on gay rights issues in 1992. Quantitative analysis of public opinion shows that, starting in 1992 and continuing through 2008, gay rights issues became more salient to the public, and opinions about gay rights began to exert a significant effect on vote choice. The study concludes with a discussion of the partisan forces that shaped the electoral significance of gay rights issues during the period from 1988 to 2008 and speculation about the role of gay rights issues in shaping future partisan electoral strategy.

  19. The rates measurement of methane hydrate formation and dissociation using micro-drilling system application for gas hydrate exploration

    Energy Technology Data Exchange (ETDEWEB)

    Bin Dou [Engineering Faculty, China Univ. of Geosciences, Wuhan (China)]|[Inst. of Petroleum Engineering, Technology Univ. of Clausthal (Germany); Reinicke, K.M. [Inst. of Petroleum Engineering, Technology Univ. of Clausthal (Germany); Guosheng Jiang; Xiang Wu; Fulong Ning [Engineering Faculty, China Univ. of Geosciences, Wuhan (China)

    2006-07-01

    When drilling through gas hydrate bearing formations, the energy supplied by virtue of the drilling process may lead to a destabilization of the hydrates surrounding the wellbore. Therefore, as the number of oil and gas fields being development in deepwater and onshore arctic environments increases, greater emphasis should be placed on quantifying the risks, gas hydrates pose to drilling operations. The qualification of these risks requires a comprehensive understanding of gas hydrate-formation and dissociation as a result of drilling induced processes. To develop the required understanding of gas hydrat formation and dissociation, the authors conducted laboratory experiments by using a micro-drilling system, to study the dissociation rates of methane hydrates contained in a tank reactor. The test facility used is a development of China University of Geosciences. The rates of methane hydrate formation and dissociation in the tank reactor were measured at steady-state conditions at pressures ranging from 0.1 to 25 MPa and temperatures ranging from -5 to 20 C. The experimental results show that the rate of hydrate formation is strongly influenced by the fluid system used to form the hydrates, pressure and temperature, with the influence of the temperature on methane hydrate dissociation being stronger than that of the pressure. Drilling speed, drilling fluids and hydrate dissociation inhibitors were also shown to influence hydrate dissociation rate. The derived results have been used to predict hydrate drilling stability for several drilling fluid systems.

  20. Ten Things Gay Men Should Discuss with Their Health Care Provider

    Science.gov (United States)

    ... Conference Newsroom Support GLMA Site Search Ten Things Gay Men Should discuss with Their Healthcare Provider ( Download . ... have identified as most commonly of concern for gay men. While not all of these items apply ...

  1. Couple-level Motivations to Test for HIV for Gay Men in Relationships

    Science.gov (United States)

    Beougher, Sean C.; Bircher, Anja E.; Chakravarty, Deepalika; Darbes, Lynae A.; Gómez Mandic, Carmen; Neilands, Torsten B.; Garcia, Carla C.; Hoff, Colleen C.

    2015-01-01

    Previous studies of HIV testing among gay men describe the motivations, facilitators and barriers, behaviors, and demographic characteristics of individuals who test. What little research focuses on HIV testing among gay men in relationships shows that they do not test regularly or, in some cases, at all – their motivations to test have not been investigated. With so little data on HIV testing for this population, and the continued privileging of individually-focused approaches, gay men in relationships fall into a blind spot of research and prevention efforts. This study examined motivations to test for HIV using qualitative data from both partners in 20 gay male couples. Analysis revealed that the partners’ motivations were either event-related (e.g., participants testing the beginning of their relationship or HIV-negative participants in an HIV-discordant relationship testing after risky episode with their discordant primary partner) or partner-related (e.g., participants testing in response to a request or suggestion to test from their primary partner or participants testing out of concern for their primary partner’s health and wellbeing). These data provide insight into relationship-oriented motivations to test for HIV for gay men in relationships and, in doing so, demonstrates their commitment to their primary partner and relationship. These motivations can be leveraged to increase HIV testing among gay men in relationships, a population that tests less often than single gay men, yet, until recently, has been underserved by prevention efforts. PMID:25550145

  2. Guidelines for Psychological Practice With Lesbian, Gay, and Bisexual Clients

    Science.gov (United States)

    American Psychologist, 2012

    2012-01-01

    The "Guidelines for Psychological Practice With Lesbian, Gay, and Bisexual Clients" provide psychologists with (a) a frame of reference for the treatment of lesbian, gay, and bisexual clients and (b) basic information and further references in the areas of assessment, intervention, identity, relationships, diversity, education, training, and…

  3. A Numerical Model for the Thermomechanical Conditions During Hydration of Early-age Concrete

    DEFF Research Database (Denmark)

    Hattel, Jesper; Thorborg, Jesper

    2003-01-01

    In the present study, a macroscopic numerical model for the thermomechanical conditions during hydration of early-age concrete is presented. The formulation is based on a semi-coupled, incremental thermomechanical model where the heat production from the hydration process is expressed in terms...... of the maturity and the thermal activation is expressed by the Arrhenius principle. The material properties are assumed to depend on the hydration process via the maturity. The discretization of the governing equations is accomplished by a control volume formulation involving a time-splitting scheme for the heat...

  4. Microstructure of natural hydrate host sediments

    International Nuclear Information System (INIS)

    Jones, K.W.; Kerkar, P.B.; Mahajan, D.; Lindquist, W.B.; Feng, H.

    2007-01-01

    There is worldwide interest in the study of natural gas hydrate because of its potential impact on world energy resources, control on seafloor stability, significance as a drilling hazard and probable impact on climate as a reservoir of a major greenhouse gas. Gas hydrates can (a) be free floating in the sediment matrix (b) contact, but do not cement, existing sediment grains, or (c) actually cement and stiffen the bulk sediment. Seismic surveys, often used to prospect for hydrates over a large area, can provide knowledge of the location of large hydrate concentrations because the hydrates within the sediment pores modify seismic properties. The ability to image a sample at the grain scale and to determine the porosity, permeability and seismic profile is of great interest since these parameters can help in determining the location of hydrates with certainty. We report here on an investigation of the structure of methane hydrate sediments at the grain-size scale using the synchrotron radiation-based computed microtomography (CMT) technique. Work has started on the measurements of the changes occurring as tetrahydrofuran hydrate, a surrogate for methane hydrate, is formed in the sediment

  5. An Examination of the Prediction of Hydrate Formation Conditions in the Presence of Thermodynamic Inhibitors

    Directory of Open Access Journals (Sweden)

    Carollina de M. Molinari O. Antunes

    Full Text Available Abstract Gas hydrates are crystalline compounds, solid structures where water traps small guest molecules, typically light gases, in cages formed by hydrogen bonds. They are notorious for causing problems in oil and gas production, transportation and processing. Gas hydrates may form at pressures and temperatures commonly found in natural gas and oil production pipelines, thus causing partial or complete pipe blockages. In order to inhibit hydrate formation, chemicals such as alcohols (e.g., ethanol, methanol, mono-ethylene glycol and salts (sodium, magnesium or potassium chloride are injected into the produced stream. The purpose of this work is to briefly review the literature on hydrate formation in mixtures containing light gases (hydrocarbons and carbon dioxide and water in the presence of thermodynamic inhibitors. Four calculation methods to predict hydrate formation in those systems were examined and compared. Three commercial packages (Multiflash®, PVTSim® and CSMGem and a hydrate prediction routine in Fortran90 using the van der Waals and Platteeuw theory and the Peng-Robinson equation of state were tested. Predictions given by the four methods were compared to independent experimental data from the literature. In general, the four methods were found to be reasonably accurate. CSMGem and Multiflash® showed the best results.

  6. Category-specificity in sexual interest in gay men and lesbians.

    Science.gov (United States)

    Rullo, Jordan E; Strassberg, Donald S; Israel, Esther

    2010-08-01

    The present study assessed the category-specificity of sexual interest of gay men and lesbians toward an understanding of the possible interaction of sex and sexual orientation that may exist in this phenomenon. Utilizing viewing time as a measure of sexual interest, we had participants (N = 99) rate the sexual appeal of sexually provocative pictures while the amount of time spent viewing each picture was inconspicuously measured. As hypothesized, same-sex oriented individuals demonstrated a category-specific pattern of sexual interest. That is, gay men and lesbians (1) viewed preferred sex pictures (i.e., of same sex) significantly longer than nonpreferred sex pictures (i.e., of opposite sex) and (2) rated preferred sex pictures as significantly more sexually appealing than nonpreferred sex pictures. Additionally, the difference in viewing times between preferred and nonpreferred sexual stimuli was not significantly different for gay men and lesbians, suggesting that lesbians are as category-specific as gay men. The implications of these findings are discussed.

  7. "You Can't Just Walk Down the Street and Meet Someone": The Intersection of Social-Sexual Networking Technology, Stigma, and Health Among Gay and Bisexual Men in the Small City.

    Science.gov (United States)

    White Hughto, Jaclyn M; Pachankis, John E; Eldahan, Adam I; Keene, Danya E

    2017-05-01

    Social-sexual networking technologies have been reported to yield both psychosocial benefits and sexual risks for gay and bisexual men, yet little research has explored how technology interacts with the social-geographical environment to shape the health of gay and bisexual men in the relatively understudied environment of small cities. This article draws on 29 semistructured interviews examining the use of social-sexual networking technologies among racially diverse gay and bisexual men in two small cities. Questions probed participants' use of technology to meet sexual partners, engagement in the gay community, and the role of virtual and nonvirtual spaces in relation to health. Findings suggest that social networking technologies can help men navigate the challenges of small cities, including small and insular gay communities, lack of dedicated gay spaces, and sexual minority stigma. However, participants also describe declines in gay community visibility and cohesion, which they attribute to technology use. The article concludes by discussing the intersections of virtual and physical space in small cities as sites for the production of health and illness.

  8. "Appearance potent"? A content analysis of UK gay and straight men's magazines.

    Science.gov (United States)

    Jankowski, Glen S; Fawkner, Helen; Slater, Amy; Tiggemann, Marika

    2014-09-01

    With little actual appraisal, a more 'appearance potent' (i.e., a reverence for appearance ideals) subculture has been used to explain gay men's greater body dissatisfaction in comparison to straight men's. This study sought to assess the respective appearance potency of each subculture by a content analysis of 32 issues of the most read gay (Attitude, Gay Times) and straight men's magazines (Men's Health, FHM) in the UK. Images of men and women were coded for their physical characteristics, objectification and nudity, as were the number of appearance adverts and articles. The gay men's magazines featured more images of men that were appearance ideal, nude and sexualized than the straight men's magazines. The converse was true for the images of women and appearance adverts. Although more research is needed to understand the effect of this content on the viewer, the findings are consistent with a more appearance potent gay male subculture. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  9. Faith and Sexual Orientation Identity Development in Gay College Men

    Science.gov (United States)

    Dunn, Merrily; Glassmann, Danny; Garrett, J. Matthew; Badaszewski, Philip; Jones, Ginny; Pierre, Darren; Fresk, Kara; Young, Dallin; Correll-Hughes, Larry

    2015-01-01

    This study examines the experiences of gay-identified college men related to their faith and sexual orientation identity development. The findings suggest that for gay-identified college men, faith and sexual orientation identity development includes examination of one's faith and sexual orientation identity, important relationships, and a desire…

  10. ‘Kids are just cruel anyway’: lesbian and gay parents talk about homophobic bullying

    OpenAIRE

    Clarke, V.; Kitzinger, C.; Potter, J.

    2004-01-01

    Psychologists recognise homophobic bullying as a serious problem for young lesbians and gay men; however, when it comes to children in lesbian and gay households the issue is not so clear cut. Whereas some psychologists sympathetic to lesbian and gay parenting regard it as a problem, most do not. Despite this, the inevitability and severe psychological consequences of homophobic bullying is a prevalent theme in discussions of lesbian and gay parenting in contexts ranging from custody cases to...

  11. Gay Immigrants and Grindr

    DEFF Research Database (Denmark)

    Shield, Andrew DJ

    2018-01-01

    In this (open-access) essay, I assess the idea that Grindr and related apps render urban gay spaces obsolete, and offer three counter-arguments based on my research with immigrants and tourists who use Grindr. In short: newcomers who use Grindr might actually bring new life to queer urban spaces...

  12. Operating without a Safety Net: Gay Male Adolescents and Emerging Adults' Experiences of Marginalization and Migration, and Implications for Theory of Syndemic Production of Health Disparities

    Science.gov (United States)

    Bruce, Douglas; Harper, Gary W.

    2011-01-01

    Health disparities among gay men (HIV, substance use, depression) have been described as a mutually occurring "syndemic" that is socially produced through two overarching dynamics: marginalization and migration. Although the syndemic theory proposes a developmental trajectory, it has been largely based on epidemiological studies of adult gay men…

  13. Gay Male Only-Children: Evidence for Low Birth Weight and High Maternal Miscarriage Rates.

    Science.gov (United States)

    Skorska, Malvina N; Blanchard, Ray; VanderLaan, Doug P; Zucker, Kenneth J; Bogaert, Anthony F

    2017-01-01

    Recent findings suggest that there may be a maternal immune response underpinning the etiology of sexual orientation of gay male only-children. This maternal immune response appears to be distinct from that which is purported to explain the classic fraternal birth order effect found in studies of male sexual orientation. We tested two predictions related to the hypothesized maternal immune response in mothers of gay male only-children: (1) elevated fetal loss among mothers who have had gay male only-children and (2) lower birth weight in gay male only-children. Mothers of at least one gay son (n = 54) and mothers of heterosexual son(s) (n = 72) self-reported their pregnancy histories, including the birth weights of newborns and number of fetal losses (e.g., miscarriages). Mothers of gay male only-children (n = 8) reported significantly greater fetal loss compared with mothers of males with four other sibship compositions (gay with no older brothers, gay with older brothers, heterosexual only-children, heterosexual with siblings) (n = 118). Also, firstborn gay male only-children (n = 4) had a significantly lower birth weight than firstborn children in the four other sibship compositions (n = 59). Duration of pregnancy was not significantly different among the groups of firstborn children in the birth weight analyses. Thus, this study found further support for a distinct pattern of maternal immune response implicated in the etiology of male sexual orientation. Mechanisms that may underlie this potential second type of maternal immune response are discussed.

  14. Voices from the Glass Closet: Lesbian and Gay Teachers Talk about Their Lives.

    Science.gov (United States)

    Kissen, Rita M.

    This study explores issues of importance to gay and lesbian teachers. It seeks to answer questions and to dramatize the damaging effects of homophobia on the lives of gay teachers, as well as all teachers and students. The project was narrative and qualitative, consisting of informal and open ended interviews of 10 self-identifies gay or lesbian…

  15. How Organisational Culture Influences Teachers' Support of Openly Gay, Lesbian and Bisexual Students

    Science.gov (United States)

    Murphy, Meghan

    2015-01-01

    In this paper, I analyse the relationship between US high schools' organisational cultures and student perceptions of responses to anti-gay language in their school. Using data from 67 interviews with young people who identified as gay, lesbian or bisexual, I compare teachers' responses to anti-gay language in schools that do and schools that do…

  16. Demographic Trends and Advocacy Experiences of Gay-Straight Alliance Advisors

    Science.gov (United States)

    Graybill, Emily C.; Varjas, Kris; Meyers, Joel; Dever, Bridget V.; Greenberg, Daphne; Roach, Andrew T.; Morillas, Catalina

    2015-01-01

    Using an ecological model, the individual-, school-, and sociocultural-level characteristics that affect gay-straight alliance (GSA) advisors were examined in the current study. The formation of GSAs has been one way that schools have sought to improve the school climate for lesbian, gay, bisexual, and transgender (LGBT) youth. Limited information…

  17. Counseling Issues for Gay Men and Lesbians Seeking Assisted Reproductive Technologies (ART)

    Science.gov (United States)

    ... for Reproductive Medicine Counseling issues to discuss with gay men and lesbians seeking assisted reproductive technology (ART) More lesbian, gay, bisexual, and transgender (LGBT) individuals and couples are ...

  18. Attitudes of Heterosexual Men and Women Toward HIV Negative and Positive Gay Men.

    Science.gov (United States)

    Norcini Pala, Andrea; Villano, Paola; Clinton, Lauren

    2017-01-01

    Attitudes of Italian heterosexual men and women toward gay men, both HIV positive and negative, are poorly investigated. Italian culture is still extremely conservative and provides limited support to the gay community (e.g., lack of same-sex marriage recognition). Consequently, gay men experience social exclusion and disparities. The present study explores the association between homophobia and closeness with sexual orientation and HIV status. 261 heterosexual Italian men and women were assessed for feelings of closeness and homophobia after reading a vignette where the character was C1: heterosexual and HIV negative; C2: gay and HIV negative; or C3: gay and HIV positive. Experiences of homophobia and closeness varied depending on gender of participant and condition assigned, and higher levels of homophobia were correlated with lower levels of closeness regardless of HIV status. Implications and future directions are discussed.

  19. Interview med professor Paul du Gay om bureaukratiets værdi

    DEFF Research Database (Denmark)

    Pors, Anja Svejgaard

    2013-01-01

    Paul du Gay er sociolog og globaliseringsprofessor ved Institut for Organisation på Copenhagen Business School. I hans forskning interesserer han sig blandt andet for bureaukratiet som styreform. Gennem årtier har bureaukratiet været genstand for omfattende kritik for dets langsommelighed......, inhumanitet og manglende fleksibilitet. Paul du Gay har taget til genmæle og forsvarer bureaukratiet som en styreform, der understøtter demokrati. I arbejdet med administration som praksis og faglighed har vi interviewet Paul du Gay om nogle af de centrale pointer i denne forskning. Samtalen kredser om...

  20. The mediation of gay men's lives: A review on gay dating app studies

    NARCIS (Netherlands)

    Wu, S. (Shangwei); J.R. Ward (Janelle)

    2018-01-01

    textabstractA growing body of literature focuses on gay men's use of mobile dating applications or “dating apps.” Running on smartphones and working with GPS, dating apps connect users to others in close geographic proximity and often in real time. These apps allow users to create profiles to

  1. Borehole Tool for the Comprehensive Characterization of Hydrate-bearing Sediments

    KAUST Repository

    Dai, Sheng; Santamarina, Carlos

    2018-01-01

    Reservoir characterization and simulation require reliable parameters to anticipate hydrate deposits responses and production rates. The acquisition of the required fundamental properties currently relies on wireline logging, pressure core testing, and/or laboratory ob-servations of synthesized specimens, which are challenged by testing capabilities and in-nate sampling disturbances. The project reviews hydrate-bearing sediments, properties, and inherent sampling effects, albeit lessen with the developments in pressure core technology, in order to develop robust correlations with index parameters. The resulting information is incorporated into a tool for optimal field characterization and parameter selection with un-certainty analyses. Ultimately, the project develops a borehole tool for the comprehensive characterization of hydrate-bearing sediments at in situ, with the design recognizing past developments and characterization experience and benefited from the inspiration of nature and sensor miniaturization.

  2. Borehole Tool for the Comprehensive Characterization of Hydrate-bearing Sediments

    KAUST Repository

    Dai, Sheng

    2018-02-01

    Reservoir characterization and simulation require reliable parameters to anticipate hydrate deposits responses and production rates. The acquisition of the required fundamental properties currently relies on wireline logging, pressure core testing, and/or laboratory ob-servations of synthesized specimens, which are challenged by testing capabilities and in-nate sampling disturbances. The project reviews hydrate-bearing sediments, properties, and inherent sampling effects, albeit lessen with the developments in pressure core technology, in order to develop robust correlations with index parameters. The resulting information is incorporated into a tool for optimal field characterization and parameter selection with un-certainty analyses. Ultimately, the project develops a borehole tool for the comprehensive characterization of hydrate-bearing sediments at in situ, with the design recognizing past developments and characterization experience and benefited from the inspiration of nature and sensor miniaturization.

  3. Borehole Tool for the Comprehensive Characterization of Hydrate-bearing Sediments

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Sheng [Georgia Inst. of Technology, Atlanta, GA (United States); Santamarina, J. Carlos [Georgia Inst. of Technology, Atlanta, GA (United States); King Abdullah Univ. of Science and Technology (KAUST), Thuwal (Saudi Arabia)

    2017-12-30

    Reservoir characterization and simulation require reliable parameters to anticipate hydrate deposits responses and production rates. The acquisition of the required fundamental properties currently relies on wireline logging, pressure core testing, and/or laboratory observations of synthesized specimens, which are challenged by testing capabilities and innate sampling disturbances. The project reviews hydrate-bearing sediments, properties, and inherent sampling effects, albeit lessen with the developments in pressure core technology, in order to develop robust correlations with index parameters. The resulting information is incorporated into a tool for optimal field characterization and parameter selection with uncertainty analyses. Ultimately, the project develops a borehole tool for the comprehensive characterization of hydrate-bearing sediments at in situ, with the design recognizing past developments and characterization experience and benefited from the inspiration of nature and sensor miniaturization.

  4. Beyond Gay-Straight Alliances

    Science.gov (United States)

    Sadowski, Michael

    2010-01-01

    Decades' worth of studies point to the importance of parental involvement in K-12 schooling. Yet when it comes to policies related to lesbian, gay, bisexual, and transgender (LGBT) students, families are often deliberately left out of the conversation, according to several leading experts in LGBT youth development. Even in schools where…

  5. “Si Nicaragua Venció”: Lesbian and Gay Solidarity with the Revolution

    Directory of Open Access Journals (Sweden)

    Emily K. Hobson

    2012-12-01

    Full Text Available This article analyzes the radical imagination of lesbian and gay activism in solidarity with the Nicaraguan Revolution. It examines the reasons US lesbian and gay radicals supported that revolution and investigates the ways that homoerotic, especially lesbian, desire shaped their solidarity. Drawing on Herbert Marcuse and Michel Foucault, the article argues that lesbian and gay radicals viewed the Nicaraguan Revolution in erotic and heterotopic terms. Posters, fliers, and interviews reveal that US activists, people of color and white, represented the Revolution and solidarity through tropes of female masculinity and women’s affection. Many Nicaraguan lesbians and gay men shared these nonnormative images of socialist change. Yet while Nicaraguans claimed Sandinismo as their own, for US activists revolution remained a distant object of desire and solidarity a “seduction,” “crush,” or embrace.  United States activists who embraced developmentalist views of Latin American sexualities remained unable to witness lesbian and gay life inside Nicaragua, while lesbian and gay Sandinistas kept silent about FSLN homophobia so as not to undermine solidarity against the Contra war. Desire served as a powerful tool for mobilizing transnational solidarity. By failing to examine desire critically, however, US activists limited their communications with Nicaraguan lesbians and gay men and weakened the relationship they sought with revolution itself.

  6. “You Can’t Just Walk Down the Street and Meet Someone”: The Intersection of Social–Sexual Networking Technology, Stigma, and Health Among Gay and Bisexual Men in the Small City

    Science.gov (United States)

    White Hughto, Jaclyn M.; Pachankis, John E.; Eldahan, Adam I.; Keene, Danya E.

    2016-01-01

    Social–sexual networking technologies have been reported to yield both psychosocial benefits and sexual risks for gay and bisexual men, yet little research has explored how technology interacts with the social–geographical environment to shape the health of gay and bisexual men in the relatively understudied environment of small cities. This article draws on 29 semistructured interviews examining the use of social–sexual networking technologies among racially diverse gay and bisexual men in two small cities. Questions probed participants’ use of technology to meet sexual partners, engagement in the gay community, and the role of virtual and nonvirtual spaces in relation to health. Findings suggest that social networking technologies can help men navigate the challenges of small cities, including small and insular gay communities, lack of dedicated gay spaces, and sexual minority stigma. However, participants also describe declines in gay community visibility and cohesion, which they attribute to technology use. The article concludes by discussing the intersections of virtual and physical space in small cities as sites for the production of health and illness. PMID:27885147

  7. Attitudes toward straight, gay male, and transsexual parenting.

    Science.gov (United States)

    Weiner, Brittany A; Zinner, Leah

    2015-01-01

    This study examined American attitudes toward transsexual and gay male parenting, compared to straight parenting. After reporting levels of transphobia, participants read a vignette regarding a couple seeking child adoption. Individuals high in transphobia perceived nontraditional couples as more emotionally unstable than straight couples and were less willing to grant custody of a child to the nontraditional couples vs. the straight couples. In addition, the transsexual couple faced more prejudice and discrimination than the gay male couple. Implications of these findings are discussed.

  8. Synthesis and hydration behavior of calcium zirconium aluminate (Ca7ZrAl6O18) cement

    International Nuclear Information System (INIS)

    Kang, Eun-Hee; Yoo, Jun-Sang; Kim, Bo-Hye; Choi, Sung-Woo; Hong, Seong-Hyeon

    2014-01-01

    Calcium zirconium aluminate (Ca 7 ZrAl 6 O 18 ) cements were prepared by solid state reaction and polymeric precursor methods, and their phase evolution, morphology, and hydration behavior were investigated. In polymeric precursor method, a nearly single phase Ca 7 ZrAl 6 O 18 was obtained at relatively lower temperature (1200 °C) whereas in solid state reaction, a small amount of CaZrO 3 coexisted with Ca 7 ZrAl 6 O 18 even at higher temperature (1400 °C). Unexpectedly, Ca 7 ZrAl 6 O 18 synthesized by polymeric precursor process was the large-sized and rough-shaped powder. The planetary ball milling was employed to control the particle size and shape. The hydration behavior of Ca 7 ZrAl 6 O 18 was similar to that of Ca 3 Al 2 O 6 (C3A), but the hydration products were Ca 3 Al 2 O 6 ·6H 2 O (C3AH6) and several intermediate products. Thus, Zr (or ZrO 2 ) stabilized the intermediate hydration products of C3A

  9. Artificial Hydration and Nutrition

    Science.gov (United States)

    ... Crisis Situations Pets and Animals myhealthfinder Food and Nutrition Healthy Food Choices Weight Loss and Diet Plans ... Your Health Resources Healthcare Management Artificial Hydration and Nutrition Artificial Hydration and Nutrition Share Print Patients who ...

  10. Hydration dependent dynamics in RNA

    International Nuclear Information System (INIS)

    Olsen, Greg L.; Bardaro, Michael F.; Echodu, Dorothy C.; Drobny, Gary P.; Varani, Gabriele

    2009-01-01

    The essential role played by local and collective motions in RNA function has led to a growing interest in the characterization of RNA dynamics. Recent investigations have revealed that even relatively simple RNAs experience complex motions over multiple time scales covering the entire ms-ps motional range. In this work, we use deuterium solid-state NMR to systematically investigate motions in HIV-1 TAR RNA as a function of hydration. We probe dynamics at three uridine residues in different structural environments ranging from helical to completely unrestrained. We observe distinct and substantial changes in 2 H solid-state relaxation times and lineshapes at each site as hydration levels increase. By comparing solid-state and solution state 13 C relaxation measurements, we establish that ns-μs motions that may be indicative of collective dynamics suddenly arise in the RNA as hydration reaches a critical point coincident with the onset of bulk hydration. Beyond that point, we observe smaller changes in relaxation rates and lineshapes in these highly hydrated solid samples, compared to the dramatic activation of motion occurring at moderate hydration

  11. Azebaycan’ın İlk Savaş Pilotu Ferruh Ağa GayıbovThe First Combat Pilot of Azerbaijan- Farrukh Gayıbov-

    Directory of Open Access Journals (Sweden)

    MUHAMMET KEMALOĞLU

    2014-06-01

    Full Text Available Ferruh Ağa Gayıbov Azerbaycanlı ilk şavaş pilotudur. İlya Muromets №16 adlı bombardıman uçağının personelidir. I.Dünya Savaşına katılmıştır. Çar ordusunda “Topçuların Tanrısı” diye kabul edilen Aliağa Şıhlinski’nin de akrabasıdır. Ferruh Ağa 2 Ekim 1891’de, Kazak ilinin Sınır Salahlı köyünde doğmuştur. Tiflis Askeri Okulunda okur. Üsteğmen rütbesinde iken 12 Eylül 1916’da Batı cephesi karargâhının emri ile Borına’ya saldırır, Almanların mevzilerini ve mevkilerini bombalar. Onun uçağına doğru 4 alman savaş uçağı saldırıya geçer. Gayıbov onların üçünü imha eder ancak uçağının aldığı darebeden dolayı yere çırparak hayatını kaybeder. Şəmistan Nəzirli’den yaptığmız “Azərbaycanın İlk Hərbi Təyyarəçisi Ferruh Ağa Gayıbov” adlı bu çeviri eser Ferruh Ağa Gayıbov’u tarihin derin sayfalarından çıkarmıştır. Abstract Ferruh Gayıbov was the first Azerbaijani combat pilot. He was the bombardier in Ilya Muromets № 16 bomber aircraft. He joined World War I. He was a relative Aliaga Şıhlinski whose name called "the God of Artillery," in the Tsarist army. Ferruh Agha was born in 2 October 1891, in the village of Salahlı Kazakh. He studied at Tbilisi Military School. When he was a first lieutenant, he attacked to the Boriana with the order of West Front Headquarter and bombed German positions and locations in September 12, 1916. Four German bomber aircraft attacked his plane. Gayıbov destroyed three of them but his plane got shot and he lost his life. Our translation of “Azərbaycanın İlk Hərbi Təyyarəçisi Ferruh Ağa Gayıbov” by Şemistan Nezirli, has revealed Ferruh Agha Gayıbov from the depths of history.

  12. Gender Nonconformity and Birth Order in Relation to Anal Sex Role Among Gay Men.

    Science.gov (United States)

    Swift-Gallant, Ashlyn; Coome, Lindsay A; Monks, D Ashley; VanderLaan, Doug P

    2018-05-01

    Androphilia is associated with an elevated number of older brothers among natal males. This association, termed the fraternal birth order effect, has been observed among gay men who exhibit marked gender nonconformity. Gender nonconformity has been linked to gay men's preferred anal sex role. The present study investigated whether these two lines of research intersect by addressing whether the fraternal birth order effect was associated with both gender nonconformity and a receptive anal sex role (243 gay men, 91 heterosexual men). Consistent with previous research, we identified the fraternal birth order effect in our sample of gay men. Also, gay men were significantly more gender-nonconforming on adulthood and recalled childhood measures compared to heterosexual men. When gay men were compared based on anal sex role (i.e., top, versatile, bottom), all groups showed significantly greater recalled childhood and adult male gender nonconformity than heterosexual men, but bottoms were most nonconforming. Only gay men with a bottom anal sex role showed evidence of a fraternal birth order effect. A sororal birth order effect was found in our sample of gay men, driven by versatiles. No significant associations were found between fraternal birth order and gender nonconformity measures. These results suggest that the fraternal birth order effect may apply to a subset of gay men who have a bottom anal sex role preference and that this subgroup is more gender-nonconforming. However, there were no significant associations between fraternal birth order and gender nonconformity at the individual level. As such, based on the present study, whether processes underpinning the fraternal birth order effect influence gender nonconformity is equivocal.

  13. Investigations into surfactant/gas hydrate relationship

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Rudy; Zhang, Guochang; Dearman, Jennifer; Woods, Charles [Swalm School of Chemical Engineering, Mississippi State University, Mississippi State, MS 39762 (United States)

    2007-03-15

    Gas hydrates have unique physical properties portending useful industrial applications of gas storage, gas separation, or water desalination. When gas hydrates were found in the early 1990s to occur naturally and abundantly in seafloors, three other primary interests and concerns emerged: potential new energy source, climate threat from their greenhouse gases, and seafloor instabilities. This paper presents research showing how anionic synthetic surfactants helped develop an industrial gas hydrate storage process for natural gas and how naturally-occurring in-situ anionic biosurfactants influence the formation and placement of gas hydrates in ocean sediments. The catalytic effects, mechanisms, and surface specificities imparted by synthetic surfactants in the gas storage process and imparted by biosurfactants in porous media are discussed. The Bacillus subtilis bacterium that is indigenous to gas hydrate mounds in the Gulf of Mexico was cultured in the laboratory. Its biosurfactant was separated and found to catalyze gas hydrates in porous media. The experiments indicate that seafloor-biosurfactants can be produced rapidly in-situ to achieve threshold concentrations whereby hydrates are promoted. The biosurfactants accumulate and promote hydrate formation on specific mineral surfaces such as sodium montmorillonite. (author)

  14. Accelerated hydration of high silica cements

    International Nuclear Information System (INIS)

    Walker, Colin; Yui, Mikazu

    2012-01-01

    Current Japanese designs for high level radioactive waste (HLW) repositories anticipate the use of both bentonite (buffer and backfill material) and cement based materials. Using hydrated Ordinary Portland Cement (OPC) as a grouting material is undesirable because the associated high pH buffer will have an undisputed detrimental effect on the performance of the bentonite buffer and backfill and of the host rock by changing its porosity. Instead, hydrated low pH cement (LopHC) grouting materials are being developed to provide a pH inferior or equal to 11 to reduce these detrimental effects. LopHC grouting materials use mixtures of superfine OPC (SOPC) clinker and silica fume (SF), and are referred as high silica cements (HSC). The focus of the present study was to identify the development of the unhydrated and hydrated mineral assemblage and the solution chemistry during the hydration of HSC. Since hydration experiments of cementitious materials are notably slow, a ball mill was used to accelerate hydration. This was done for two reasons. Firstly, to develop a method to rapidly hydrate cement based materials without the need for higher temperatures (which can alter the mineral assemblage), and secondly, to ensure that the end point of hydration was reached in a reasonable time frame and so to realize the final mineralogy and solution chemistry of hydrated HSC

  15. Relational aggression and victimization in gay male relationships: the role of internalized homophobia.

    Science.gov (United States)

    Kelley, Thomas M; Robertson, Richard A

    2008-01-01

    This article presents two studies that are the first to examine relational aggression and relational victimization in gay male peer relationships. A qualitative pilot study provides a strong rationale for a subsequent empirical investigation of 100 young adult, self-identified gay males. Results of both studies demonstrate that relational aggression and relational victimization are common experiences in gay male relationships. They also reveal forms of relational aggression and victimization that appear to be unique to gay males (e.g., outing). Results of the empirical study found significant relations between engaging in relational aggression against gay males and experiencing relational victimization and between experiencing relational victimization and internalized homophobia. However, there was no significant correlation between internalized homophobia and engaging in relational aggression. A multiple regression analysis found that experiencing relational victimization was correlated more strongly with the combination of engaging in relational aggression and internalized homophobia together than with relational aggression alone. Results are discussed within the framework of Allport's "traits due to victimization" theory and Meyer's theory of "minority stress." Implications for the prevention of relational aggression/victimization in gay male relationships are offered. Copyright 2008 Wiley-Liss, Inc.

  16. A Hydrate Database: Vital to the Technical Community

    Directory of Open Access Journals (Sweden)

    D Sloan

    2007-06-01

    Full Text Available Natural gas hydrates may contain more energy than all the combined other fossil fuels, causing hydrates to be a potentially vital aspect of both energy and climate change. This article is an overview of the motivation, history, and future of hydrate data management using a CODATA vehicle to connect international hydrate databases. The basis is an introduction to the Gas Hydrate Markup Language (GHML to connect various hydrate databases. The accompanying four articles on laboratory hydrate data by Smith et al., on field hydrate data by L?wner et al., on hydrate modeling by Wang et al., and on construction of a Chinese gas hydrate system by Xiao et al. provide details of GHML in their respective areas.

  17. HIV risk and sense of community: French gay male discourses on barebacking.

    Science.gov (United States)

    Girard, Gabriel

    2016-01-01

    This paper analyses the use of the concept of 'barebacking' as a risk category in the discourses of French gay men. It discusses how the rise and spread of the term barebacking contributes to reframing gay men's personal experiences of HIV prevention and their sense of belonging (or a lack thereof) to a gay community. The study is based on 30 qualitative interviews with French gay men conducted between 2005 and 2008. An import from the USA, the term barebacking emerged publicly in France in the late-1990s and was first used to describe intentionally unprotected sexual practices. Debates surrounding this risk category were marked by violent controversy over its use and its definition among HIV prevention actors. There remains a general lack of consensus on the definition of the term, despite its use by activists, in porn culture and in the daily discourses of gay men. By focusing on the relational roots of risk perception, I consider how uses of the term barebacking invoke a moral framework around risk taking.

  18. "Salvation Armany": Gay sensibility between high fashion and everyday dressing practices

    Directory of Open Access Journals (Sweden)

    Ildiko Erdei

    2016-03-01

    Full Text Available The paper considers the link between gay people and the fashion world, their role and and relationship to clothing in different fashion registries, as pointed out by Jennifer Craik, in high and in everyday fashion. Based on secondary literature the paper will outline current problematizations of the relationship between gays and high fashion, as well as their importance for the history of high, elite, designer fashion. In the second part of the paper, based on empirical research on the behavior of gay people in Belgrade fashion-wise, the discourses and practices of everyday fashion within the gay population of the capital of Serbia are presented, with a focus on three aspects of dressing practices: consumption of fashionable clothing and accessories with a focus on shopping, evaluation and hierarchization of branded clothing and the skill of combining them which respondents believe represents the key to their unique styles.

  19. Effects of Minority Stress, Group-Level Coping, and Social Support on Mental Health of German Gay Men.

    Science.gov (United States)

    Sattler, Frank A; Wagner, Ulrich; Christiansen, Hanna

    2016-01-01

    According to epidemiological studies, gay men are at a higher risk of mental disorders than heterosexual men. In the current study, the minority stress theory was investigated in German gay men: 1) it was hypothesized that minority stressors would positively predict mental health problems and that 2) group-level coping and social support variables would moderate these predictions negatively. Data from 1,188 German self-identified gay men were collected online. The questionnaire included items about socio-demographics, minority stress (victimization, rejection sensitivity, and internalized homonegativity), group-level coping (disclosure of sexual orientation, homopositivity, gay affirmation, gay rights support, and gay rights activism), and social support (gay social support and non-gay social support). A moderated multiple regression was conducted. Minority stressors positively predicted mental health problems. Group-level coping did not interact with minority stressors, with the exception of disclosure and homopositivity interacting marginally with some minority stressors. Further, only two interactions were found for social support variables and minority stress, one of them marginal. Gay and non-gay social support inversely predicted mental health problems. In addition, disclosure and homopositivity marginally predicted mental health problems. The findings imply that the minority stress theory should be modified. Disclosure does not have a relevant effect on mental health, while social support variables directly influence mental health of gay men. Group-level coping does not interact with minority stressors relevantly, and only one relevant interaction between social support and minority stress was found. Further longitudinal or experimental replication is needed before transferring the results to mental health interventions and prevention strategies for gay men.

  20. Parental influences on the self-esteem of gay and lesbian youths: a reflected appraisals model.

    Science.gov (United States)

    Savin-Williams, R C

    1989-01-01

    Based on a population of 317 gay and lesbian youths, the current investigation explores the appropriateness of a reflected appraisals perspective in predicting the degree to which parental attitudes, as perceived by youth, affects their self-esteem and comfortableness being gay. A lesbian was most comfortable with her sexual orientation if she also reported that her parents accepted her homosexuality; these variables did not, however, predict her level of self-esteem. Among the gay males, parental acceptance predicted comfortable being gay if the parents were also perceived as important components of a youth's self-worth; a male most comfortable with his sexual orientation had the highest level of self-esteem. Results are discussed in terms of: (a) sex of parent, (b) sex-role development, (c) comparisons of gays and lesbians, and (d) research on gay and lesbian youth.

  1. Calcium aluminates hydration in presence of amorphous SiO2 at temperatures below 90 deg. C

    International Nuclear Information System (INIS)

    Rivas Mercury, J.M.; Turrillas, X.; Aza, A.H. de; Pena, P.

    2006-01-01

    The hydration behaviour of Ca 3 Al 2 O 6 , Ca 12 Al 14 O 33 and CaAl 2 O 4 with added amorphous silica at 40, 65 and 90 deg. C has been studied for periods ranging from 1 to 31 days. In hydrated samples crystalline phases like katoite (Ca 3 Al 2 (SiO 4 ) 3- x (OH) 4 x ) and gibbsite, Al(OH) 3 , were identified, likewise amorphous phases like Al(OH) x , calcium silicate hydrates, C-S-H, and calcium aluminosilicate hydrates, C-S-A-H, were identified. The stoichiometry of Ca 3 Al 2 (SiO 4 ) 3- x (OH) 4 x (0≤3-x≤0.334), which was the main crystalline product, was established by Rietveld refinement of X-ray and neutron diffraction data and by transmission electron microscopy. - Graphical abstract: Katoite, Ca 3 Al 2 (SiO 4 ) 3- x (OH) 4 x (0≤3-x≤0.334), was identified besides gibbsite, Al(OH) 3 , as a crystalline stable hydration products in Ca 3 Al 2 O 6 , Ca 12 Al 14 O 33 and CaAl 2 O 4 hydrated with added amorphous silica between 40 and 90 deg. C

  2. Gay guys using gay language: friendship, shared values and the intent-context-effect matrix.

    Science.gov (United States)

    McCormack, Mark; Wignall, Liam; Morris, Max

    2016-12-01

    This article draws on in-depth interviews with 35 openly gay male undergraduates from four universities in England to develop an understanding of the changing nature of language related to homosexuality. In addition to finding a diminution in the prevalence of homophobic language, we demonstrate that participants maintain complex and nuanced understandings of phrases that do not use homophobic pejoratives, such as 'that's so gay'. The majority of participants rejected the notion that these phrases are inherently homophobic, instead arguing that the intent with which they are said and the context in which they are used are vital in understanding their meaning and effect. We conceptualize an intent-context-effect matrix to understand the interdependency of these variables. Highlighting the situated nature of this matrix, we also demonstrate the importance of the existence of shared norms between those saying and hearing the phrase when interpreting such language. © London School of Economics and Political Science 2016.

  3. Storage capacity of hydrogen in gas hydrates

    International Nuclear Information System (INIS)

    Tsuda, Takaaki; Ogata, Kyohei; Hashimoto, Shunsuke; Sugahara, Takeshi; Sato, Hiroshi; Ohgaki, Kazunari

    2010-01-01

    The storage capacity of H 2 in the THF, THT, and furan hydrates was studied by p-V-T measurements. We confirmed that the storage and release processes of H 2 in all hydrates could be performed reversibly by pressure swing without destroying of hydrate cages. H 2 absorption in both THT and furan hydrates is much faster than THF hydrate in spite of same unit-cell structure. On the other hand, the storage amounts of H 2 are coincident in the all additive hydrates and would reach at about 1.0 mass% asymptotically.

  4. Properties of samples containing natural gas hydrate from the JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well, determined using Gas Hydrate And Sediment Test Laboratory Instrument (GHASTLI)

    Science.gov (United States)

    Winters, W.J.

    1999-01-01

    As part of an ongoing laboratory study, preliminary acoustic, strength, and hydraulic conductivity results are presented from a suite of tests conducted on four natural-gas-hydrate-containing samples from the Mackenzie Delta JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well. The gas hydrate samples were preserved in pressure vessels during transport from the Northwest Territories to Woods Hole, Massachusetts, where multistep tests were performed using GHASTLI (Gas Hydrate And Sediment Test Laboratory Instrument), which recreates pressure and temperature conditions that are stable for gas hydrate. Properties and changes in sediment behaviour were measured before, during, and after controlled gas hydrate dissociation. Significant amounts of gas hydrate occupied the sample pores and substantially increased acoustic velocity and shear strength.

  5. Thermodynamic inhibitor performance extender that, effectively and economically prevent hydrate formation in the oil field production systems

    Energy Technology Data Exchange (ETDEWEB)

    Allenson, Stephen; Johnston, Angela [Nalco Energy Services, Sugar Land, TX (United States)

    2008-07-01

    This paper presents the development of a new additive that was developed to improve the effectiveness of the treatment two to four fold when added to the thermodynamic hydrate inhibitor (THI). Consequently, the THI/additive treatment can now enable the system to handle two to four times the amount of water production or can allow treatment of the same amount of water at half to quarter the dosage of THI. This new additive extends the performance of the THI and allows for a significant increase in production or a significant drop in the amount of THI usage with a corresponding drop in cost. This paper will further discuss the overall process of THI enhancement and will present several case studies where the enhanced THI has been successfully applied. (author)

  6. Mastery, Isolation, or Acceptance: Gay and Bisexual Men's Construction of Aging in the Context of Sexual Embodiment After Prostate Cancer.

    Science.gov (United States)

    Ussher, Jane M; Rose, Duncan; Perz, Janette

    2017-01-01

    Age is the predominant risk factor for developing prostate cancer, leading to its description as an "older man's disease." Changed sexual embodiment is a concern for men who develop prostate cancer, often compounding experiences of age-related sexual decline. Although research has examined heterosexual men's experiences of aging in the context of sexual embodiment after prostate cancer, gay and bisexual men have received little attention. This qualitative study used a material-discursive analysis, drawing on positioning theory and intersectionality, to explore constructions of aging following prostate cancer in 46 gay or bisexual men. Thematic decomposition of one-to-one interviews identified three subject positions: "mastering youth," involving maintaining an active sex life through biomedical interventions, accessing commercial sex venues, or having sex with younger men; "the lonely old recluse," involving self-positioning as prematurely aged and withdrawal from a gay sexual scene; and "accepting embodied aging," involving the incorporation of changed sexual function into intimate relationships and finding pleasure through nonsexual activities. These subject positions are conceptualized as the product of intersecting masculine and gay identities, interpreted in relation to broader cultural discourses of "new aging" and "sexual health," in which sexual activity is conceptualized as a lifelong goal.

  7. Influence of fluorosurfactants on hydrate formation rates

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C.U.; Jeong, K.E.; Chae, H.J.; Jeong, S.Y. [Korea Reasearch Inst. of Chemical Technology, Alternative Chemicals/Fuel Research Center, Yuseong-Gu, Daejon (Korea, Republic of)

    2008-07-01

    Gas hydrates, or clathrates, are ice-like solids that forms when natural gas is in contact with liquid water or ice under high pressure and low temperature. There is significant interest in studying the storage and transportation of gas in the form of hydrates. However, a critical problem impacting the industrial application of gas hydrates for storage and transportation of natural gas is the slow formation rate of natural gas hydrate. Researchers have previously reported on the promotion effect of some additives on gas hydrate formation and hydrate gas content. Fluorosurfactants are significantly superior to nonfluorinated surfactants in wetting action, as well as stability in harsh environments, both thermal and chemical. This paper discussed an experimental investigation into the effects of fluorosurfactants with different ionic types on the formation of methane hydrate. The surfactants used were FSN-100 of DuPont Zonyl as non-ionic surfactant and FC-143 of DuPont as anionic surfactant. The paper discussed the experimental apparatus for methane hydrate formation. It also discussed hydrate formation kinetics and the series of hydrate formation experiments that were conducted in the presence of fluorosurfactants. Last, the paper explored the results of the study. It was concluded that anionic fluorosurfactant of FC-143 had a better promoting effect on methane hydrate formation compared with nonionic surfactant of FSN-100. 8 refs., 2 tabs., 2 figs.

  8. Clathrate Hydrates for Thermal Energy Storage in Buildings: Overview of Proper Hydrate-Forming Compounds

    Directory of Open Access Journals (Sweden)

    Beatrice Castellani

    2014-09-01

    Full Text Available Increasing energy costs are at the origin of the great progress in the field of phase change materials (PCMs. The present work aims at studying the application of clathrate hydrates as PCMs in buildings. Clathrate hydrates are crystalline structures in which guest molecules are enclosed in the crystal lattice of water molecules. Clathrate hydrates can form also at ambient pressure and present a high latent heat, and for this reason, they are good candidates for being used as PCMs. The parameter that makes a PCM suitable to be used in buildings is, first of all, a melting temperature at about 25 °C. The paper provides an overview of groups of clathrate hydrates, whose physical and chemical characteristics could meet the requirements needed for their application in buildings. Simulations with a dynamic building simulation tool are carried out to evaluate the performance of clathrate hydrates in enhancing thermal comfort through the moderation of summer temperature swings and, therefore, in reducing energy consumption. Simulations suggest that clathrate hydrates have a potential in terms of improvement of indoor thermal comfort and a reduction of energy consumption for cooling. Cooling effects of 0.5 °C and reduced overheating hours of up to 1.1% are predicted.

  9. Study on gas hydrate as a new energy resource in the 21th century

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Byeong-Jae; Kwak Young-Hoon; Kim, Won-Sik [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    Natural gas hydrate, a special type of clathrate hydrates, is a metastable solid compound which mainly consists of methane and water, and generally called as gas hydrate. It is stable in the specific low-temperature/high-pressure conditions. Gas hydrates play an important role as major reservoir of methane on the earth. On the other hand, the formation and dissociation of gas hydrates could cause the plugging in pipeline, gas kick during production, atmospheric pollution and geohazard. To understand the formation and dissociation of the gas hydrate, the experimental equilibrium conditions of methane hydrate were measured in pure water, 3 wt.% NaCl and MgCl{sub 2} solutions. The equilibrium conditions of propane hydrates were also measured in pure water. The relationship between methane hydrate formation time and overpressure was also analyzed through the laboratory work. The geophysical surveys using air-gun system and multibeam echo sounder were implemented to develop exploration techniques and to evaluate the gas hydrate potential in the East Sea, Korea. General indicators of submarine gas hydrates on seismic data is commonly inferred from the BSR developed parallel to the see floor, amplitude blanking at the upper part of the BSR, and phase reversal and decrease of the interval velocity at BSR. The field data were processed using Geobit 2.9.5 developed by KIGAM to detect the gas hydrate indicators. The accurate velocity analysis was performed by XVA (X-window based Velocity Analysis). Processing results show that the strong reflector occurred parallel to the sea floor were shown at about 1800 ms two way travel time. The interval velocity decrease at this strong reflector and at the reflection phase reversal corresponding to the reflection at the sea floor. Gas hydrate stability field in the study area was determined using the data of measured hydrate equilibrium condition, hydrothermal gradient and geothermal gradient. The depth of BSR detected in the seismic

  10. Destabilizing Anti-Gay Environments through Gay-Straight Alliances: Possibilities and Limitations through Shifting Discourses

    Science.gov (United States)

    Currie, Sean; Mayberry, Maralee; Chenneville, Tiffany

    2012-01-01

    Drawing upon research with Gay-Straight Alliance (GSA) advisors, high-school principals, and two district-level administrators, we examine the potential and limits of the safe-space discourse that encompasses the aims of GSAs. We argue that this discourse conceals heteronormative school environments, which supplies the groundwork for hostility…

  11. Gay-Lussac Did Better Than He Knew

    Science.gov (United States)

    Holbrow, Charles H.; Amato, Joseph C.

    2011-04-01

    In his 1802 paper Joseph Louis Gay-Lussac reported the first definitive experimental evidence that many different gases exhibit the same fractional expansion of volume when heated. This property is known as Charles Law, Amontons Law, Dalton's Law, or the law of volumes. Gay-Lussac concluded from his experiments that many gases expand by 37.5% when heated from 0 ,oC to 100,oC. Although his result is within 2.5% of the modern value of 36.6% = 100/273.15, the discrepancy is surprising because his direct and simple experimental method allowed him to measure changes in volume with a precision of a few tenths of a percent. An examination of his original paper suggests, however, that he did not take into account that his measurements of the initial and final volumes of gas were made at slightly different pressures. With reasonable assumptions about the diagrams in his paper, one can use Pascal's law and the ideal gas law to correct the measured volumes so that they correspond to the same initial and final pressure. With this correction the results imply δV/V = .366. Gay-Lussac did better than he knew.

  12. Effects of Minority Stress, Group-Level Coping, and Social Support on Mental Health of German Gay Men.

    Directory of Open Access Journals (Sweden)

    Frank A Sattler

    Full Text Available According to epidemiological studies, gay men are at a higher risk of mental disorders than heterosexual men. In the current study, the minority stress theory was investigated in German gay men: 1 it was hypothesized that minority stressors would positively predict mental health problems and that 2 group-level coping and social support variables would moderate these predictions negatively.Data from 1,188 German self-identified gay men were collected online. The questionnaire included items about socio-demographics, minority stress (victimization, rejection sensitivity, and internalized homonegativity, group-level coping (disclosure of sexual orientation, homopositivity, gay affirmation, gay rights support, and gay rights activism, and social support (gay social support and non-gay social support. A moderated multiple regression was conducted.Minority stressors positively predicted mental health problems. Group-level coping did not interact with minority stressors, with the exception of disclosure and homopositivity interacting marginally with some minority stressors. Further, only two interactions were found for social support variables and minority stress, one of them marginal. Gay and non-gay social support inversely predicted mental health problems. In addition, disclosure and homopositivity marginally predicted mental health problems.The findings imply that the minority stress theory should be modified. Disclosure does not have a relevant effect on mental health, while social support variables directly influence mental health of gay men. Group-level coping does not interact with minority stressors relevantly, and only one relevant interaction between social support and minority stress was found. Further longitudinal or experimental replication is needed before transferring the results to mental health interventions and prevention strategies for gay men.

  13. A European Seal of Approval for 'gay' businesses: findings from an HIV-prevention pilot project.

    Science.gov (United States)

    Sherriff, Nigel; Gugglberger, Lisa

    2014-05-01

    'Gay' businesses can be important settings through which to deliver health promotion interventions to vulnerable populations, such as men who have sex with men (MSM) regarding HIV prevention. This article draws on data from the European Everywhere project, which represents the first scheme to develop and pre-test a common framework for HIV/STI prevention in 'gay' businesses across eight European countries. The scientific basis of the Everywhere framework was developed using a comprehensive consensus-building process over 30 months. This process included: formative scoping research; interviews with 54 'gay' businesses; meetings/workshops with representatives from project partners, 'gay' businesses, public health administrations and external experts; 15 interviews and three focus groups with project partners; a five-month pilot action phase in eight countries, together with support from the project's Advisory Group; and all Everywhere project partners including the Scientific Steering Committee. A voluntary European code setting out differentiated HIV/STI-prevention standards for 'gay' businesses (including sex venues, 'gay' and 'gay' friendly social spaces, travel agencies, hotels, dating websites) was developed and piloted in eight European cities. During a five-month pilot action, 83 'gay' businesses were certified with the Everywhere Seal of Approval representing a considerable increase on the expected pilot target of 30. Everywhere offers a major contribution to the public health and/or health promotion field in the form of a practical, policy-relevant, settings-based HIV-prevention framework for 'gay' businesses that is common across eight European countries. Findings suggest that a European-wide model of prevention is acceptable and feasible to businesses.

  14. Gender-role's attitude, perceived similarity, and sexual prejudice against gay men.

    Science.gov (United States)

    Falomir-Pichastor, Juan Manuel; Martínez, Carmen; Paterna, Consuelo

    2010-11-01

    Two hundred and twenty-six heterosexual participants (115 women and 111 men) were asked to indicate their attitude toward gender-roles, their perceived similarities with gay men, and their attitude toward gay men (i.e., sexual prejudice). As expected, male participants showed more sexual prejudice than female participants, and perceived dissimilarities were related to a greater sexual prejudice. Support for gender-roles was related to sexual prejudice for male participants, but not for female participants. More interestingly, the three-way interaction suggested that perceived similarities moderated the link between gender-roles and sexual prejudice among heterosexual men, but not among heterosexual women. Attitude in favor of traditional gender-roles was related to sexual prejudice for male participants who perceived gay men as different, but not for those who perceived gay men as similar. These findings are discussed in terms of the defensive function of men's attitude toward homosexuality as a result of threat to masculinity.

  15. Characterizing Natural Gas Hydrates in the Deep Water Gulf of Mexico: Applications for Safe Exploration and Production Activities

    Energy Technology Data Exchange (ETDEWEB)

    Bent, Jimmy

    2014-05-31

    In 2000 Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deep water portion of the Gulf of Mexico (GOM). Chevron is an active explorer and operator in the Gulf of Mexico and is aware that natural gas hydrates need to be understood to operate safely in deep water. In August 2000 Chevron worked closely with the National Energy Technology Laboratory (NETL) of the United States Department of Energy (DOE) and held a workshop in Houston, Texas to define issues concerning the characterization of natural gas hydrate deposits. Specifically, the workshop was meant to clearly show where research, the development of new technologies, and new information sources would be of benefit to the DOE and to the oil and gas industry in defining issues and solving gas hydrate problems in deep water.

  16. Comparing Heterosexuals' and Gay Men/Lesbians' Responses to Relationship Problems and the Effects of Internalized Homophobia on Gay Men/Lesbians' Responses to Relationship Problems in Turkey.

    Science.gov (United States)

    Okutan, Nur; Buyuksahin Sunal, Ayda; Sakalli Ugurlu, Nuray

    2017-01-01

    The purpose of the present study was twofold: (1) to investigate the effects of sexual orientation (heterosexuals and gay men/lesbians) and gender difference on responses to romantic relationship problems (Exit, Voice, Loyalty, and Neglect [EVLN] responses) and of perceived partner's EVLN responses in Turkey, and (2) to examine whether internalized homophobia was associated with EVLN responses and perceived partner's EVLN responses for gay men and lesbians. Responses to Dissatisfaction Scale-Accommodation Instrument, Internalized Homophobia, and Demographics Information were administered to 187 participants (44 lesbians, 44 gay men, 53 heterosexual women, 46 heterosexual men).The MANCOVA results showed that men reported higher loyalty than women, whereas women presented more exit responses than men. Further, the interactions between gender and sexual orientation on the participants' EVLN responses and on the perceived partner's EVLN responses were significant. With respect to heterosexual women, heterosexual men displayed more loyalty responses. Lesbians had higher scores on loyalty than did heterosexual women. Lesbians also had higher scores on perceived partner's exit response than did heterosexual women and gay men. On the contrary, heterosexual women reported more perceived partner's voice response than lesbians. In addition, lesbians reported higher perceived partner's neglect responses than heterosexual women. Compared to heterosexual women, heterosexual men reported higher perceived partner's exit response. Finally, internalized homophobia was associated with destructive responses for both lesbians and gay men.

  17. Why Parenthood, and Why Now?: Gay Men’s Motivations for Pursuing Parenthood

    OpenAIRE

    Goldberg, Abbie E.; Downing, Jordan B.; Moyer, April M.

    2012-01-01

    The current qualitative study of 35 pre-adoptive gay male couples (70 men) examined gay men’s motivations to parent and their reasons for pursuing parenthood at the current time. Similar to heterosexual couples, gay men described a range of psychologically-oriented reasons as shaping their decision to become parents. Some of these (e.g., desire to teach a child tolerance) may have been uniquely shaped by their sexual minority status, and others (e.g., desire to give a child a good home) in pa...

  18. Hydration and nutrition knowledge in adolescent swimmers. Does water intake affect urine hydration markers after swimming?

    Directory of Open Access Journals (Sweden)

    Cesare Altavilla

    2017-12-01

    Full Text Available Little data exists regarding nutritional knowledge and hydration in adolescent swimmers. The aim of this study was to assess the level of nutrition and hydration knowledge and to describe the fluid balance in adolescent swimmers during training. A study was carried out with a cross-sectional descriptive part and a longitudinal part with repeated measurements over five swimming sessions. Eighty-six adolescent swimmers completed a questionnaire to assess their sport nutrition and hydration knowledge. Fluid balance and urine hydration markers were studied during training. Swimmers showed a limited nutrition knowledge (33.26 % ± SD 12.59 and meagre hydration knowledge (28.61 % ± SD 28.59. Females showed lower scores than male swimmers in nutrition and hydration knowledge. Based on urine specific gravity, swimmers started the training close to the euhydrated threshold (1.019 g/mL ± SD 0.008. Although urine specific gravity and urine colour were reduced after the training, there were minimal changes in body mass (-0.12 Kg ± SD 0.31. Sweat loss (2.67 g/min ± SD 3.23 and the net changes in the fluid balance (-0.22 % ± SD 0.59 were low. The poor knowledge in nutrition and hydration encountered in the swimmers can justify the development of a strategy to incorporate nutritional education programmes for this group. Body water deficit from swimming activity seems to be easily replaced with the water intake to maintain hydration. After the training, the urine of swimmers was diluted regardless of their water intake. Dilution of urine did not reflect real hydration state in swimming.

  19. Geologic implications of gas hydrates in the offshore of India: results of the National Gas Hydrate Program Expedition 01

    Science.gov (United States)

    Collett, Timothy S.; Boswell, Ray; Cochran, J.R.; Kumar, Pushpendra; Lall, Malcolm; Mazumdar, Aninda; Ramana, Mangipudi Venkata; Ramprasad, Tammisetti; Riedel, Michael; Sain, Kalachand; Sathe, Arun Vasant; Vishwanath, Krishna

    2014-01-01

    The Indian National Gas Hydrate Program Expedition 01 (NGHP-01) is designed to study the occurrence of gas hydrate along the passive continental margin of the Indian Peninsula and in the Andaman convergent margin, with special emphasis on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these two diverse settings. The NGHP-01 expedition established the presence of gas hydrates in the Krishna-Godavari and Mahanadi Basins, and the Andaman Sea. The expedition discovered in the Krishna-Godavari Basin one of the thickest gas hydrate accumulations ever documented, in the Andaman Sea one of the thickest and deepest gas hydrate stability zones in the world, and established the existence of a fully developed gas hydrate petroleum system in all three basins.

  20. The expression of proinflammatory genes in epidermal keratinocytes is regulated by hydration status.

    Science.gov (United States)

    Xu, Wei; Jia, Shengxian; Xie, Ping; Zhong, Aimei; Galiano, Robert D; Mustoe, Thomas A; Hong, Seok J

    2014-04-01

    Mucosal wounds heal more rapidly, exhibit less inflammation, and are associated with minimal scarring when compared with equivalent cutaneous wounds. We previously demonstrated that cutaneous epithelium exhibits an exaggerated response to injury compared with mucosal epithelium. We hypothesized that treatment of injured skin with a semiocclusive dressing preserves the hydration of the skin and results in a wound healing phenotype that more closely resembles that of mucosa. Here we explored whether changes in hydration status alter epidermal gene expression patterns in rabbit partial-thickness incisional wounds. Using microarray studies on injured epidermis, we showed that global gene expression patterns in highly occluded versus non-occluded wounds are distinct. Many genes including IL-1β, IL-8, TNF-α (tumor necrosis factor-α), and COX-2 (cyclooxygenase 2) are upregulated in non-occluded wounds compared with highly occluded wounds. In addition, decreased levels of hydration resulted in an increased expression of proinflammatory genes in human ex vivo skin culture (HESC) and stratified keratinocytes. Hierarchical analysis of genes using RNA interference showed that both TNF-α and IL-1β regulate the expression of IL-8 through independent pathways in response to reduced hydration. Furthermore, both gene knockdown and pharmacological inhibition studies showed that COX-2 mediates the TNF-α/IL-8 pathway by increasing the production of prostaglandin E2 (PGE2). IL-8 in turn controls the production of matrix metalloproteinase-9 in keratinocytes. Our data show that hydration status directly affects the expression of inflammatory signaling in the epidermis. The identification of genes involved in the epithelial hydration pathway provides an opportunity to develop strategies to reduce scarring and optimize wound healing.

  1. Attitudes of physicians practicing in New Mexico toward gay men and lesbians in the profession.

    Science.gov (United States)

    Ramos, M M; Téllez, C M; Palley, T B; Umland, B E; Skipper, B J

    1998-04-01

    To examine the attitudes of physicians practicing in New Mexico toward gay and lesbian medical students, house officers, and physician colleagues. In May 1996, the authors mailed a questionnaire with demographic and attitude questions to 1,949 non-federally employed physicians practicing in New Mexico. The questionnaire consisted of questions dealing with medical school admission, residency training, and referrals to colleagues. The response rate was 53.6%. Of all the responding physicians, 4.3% would refuse medical school admission to applicants known to be gay or lesbian. Respondents were most opposed to gay and lesbian physicians' seeking residency training in obstetrics and gynecology (10.1%), and least opposed to their seeking residency training in radiology (4.3%). Disclosure of homosexual orientation would also threaten referrals to gay and lesbian obstetrician-gynecologists (11.4%) more than to gay or lesbian physicians in other specialties. Physicians' attitudes toward gay and lesbian medical students, house officers, and physician colleagues seem to have improved considerably from those reported previously in the literature. However, gay men and lesbians in medicine continue to face opposition in their medical training and in their pursuit of specialty practice.

  2. Negotiating gay men's relationships: how are monogamy and non-monogamy experienced and practised over time?

    Science.gov (United States)

    Philpot, Steven P; Duncan, Duane; Ellard, Jeanne; Bavinton, Benjamin R; Grierson, Jeffrey; Prestage, Garrett

    2017-11-07

    When viewed over time, many gay men's relationships are not static, or firmly fixed to monogamy or non-monogamy. This paper uses in-depth interviews with 61 Australian gay men to explore how monogamy and non-monogamy are experienced over time, expectations of what constitutes the norms regarding gay men's relationships and how couples experience and practices change. Although some gay men may idealise monogamy, particularly at the beginning of a relationship, it is often experienced as temporary. Non-monogamy is often seen as a likely prospect for gay relationships owing to the social and cultural norms that operate in gay communities. These expected trajectories are reflected in practice - many relationships begin monogamously and then become non-monogamous over time. While the application of 'rules', experimentation and flexibility can facilitate change, couples may struggle to navigate new territory as their relationship structures shift. This is particularly the case when partners value monogamy and non-monogamy differently, or when one partner's values change. These findings shed light on how gay men approach change to the status of 'fidelity' within their relationships, and the tensions and opportunities that change can produce for couples.

  3. The mediation of gay men’s lives: A review on gay dating app studies

    NARCIS (Netherlands)

    Wu, S.; Ward, J.

    2018-01-01

    textabstractA growing body of literature focuses on gay men's use of mobile dating applications or “dating apps.” Running on smartphones and working with GPS, dating apps connect users to others in close geographic proximity and often in real time. These apps allow users to create profiles to

  4. SOMOS: Evaluation of an HIV Prevention Intervention for Latino Gay Men

    Science.gov (United States)

    Vega, Miriam Y.; Spieldenner, Andrew R.; DeLeon, Dennis; Nieto, Bolivar X.; Stroman, Carolyn A.

    2011-01-01

    Latino gay men face multiple barriers to human immunodeficiency virus (HIV) prevention, in particular a lack of intervention programs that integrate prevention messages with cultural norms and address issues of social marginalization from multiple communities (gay community and Latino community), homophobia and racism. In order to address these…

  5. Male Archetypes as Resources for Homosexual Identity Development in Gay Men.

    Science.gov (United States)

    McFarland, William P.; McMahon, Timothy R.

    1999-01-01

    The male archetypes of king, lover, magician, and warrior provide important and timeless insights into mature masculine qualities. Homosexual identity development models describe tasks that confront gay men as they move through the identity development process. Proposes that by understanding the metaphor of male archetypes, gay men will discover…

  6. Evaluation and analysis method for natural gas hydrate storage and transportation processes

    International Nuclear Information System (INIS)

    Hao Wenfeng; Wang Jinqu; Fan Shuanshi; Hao Wenbin

    2008-01-01

    An evaluation and analysis method is presented to investigate an approach to scale-up a hydration reactor and to solve some economic problems by looking at the natural gas hydrate storage and transportation process as a whole. Experiments with the methane hydration process are used to evaluate the whole natural gas hydrate storage and transportation process. The specific contents and conclusions are as follows: first, batch stirring effects and load coefficients are studied in a semi-continuous stirred-tank reactor. Results indicate that batch stirring and appropriate load coefficients are effective in improving hydrate storage capacity. In the experiments, appropriate values for stirring velocity, stirring time and load coefficient were found to be 320 rpm, 30 min and 0.289, respectively. Second, throughput and energy consumption of the reactor for producing methane hydrates are calculated by mass and energy balance. Results show that throughput of this is 1.06 kg/d, with a product containing 12.4% methane gas. Energy consumption is 0.19 kJ, while methane hydrates containing 1 kJ heat are produced. Third, an energy consumption evaluation parameter is introduced to provide a single energy consumption evaluation rule for different hydration reactors. Parameter analyses indicate that process simplicity or process integration can decrease energy consumption. If experimental gas comes from a small-scale natural gas field and the energy consumption is 0.02 kJ when methane hydrates containing 1 kJ heat are produced, then the decrease is 87.9%. Moreover, the energy consumption evaluation parameter used as an economic criterion is converted into a process evaluation parameter. Analyses indicate that the process evaluation parameter is relevant to technology level and resource consumption for a system, which can make it applicable to economic analysis and venture forecasting for optimal capital utilization

  7. Simulation and Characterization of Methane Hydrate Formation

    Science.gov (United States)

    Dhakal, S.; Gupta, I.

    2017-12-01

    The ever rising global energy demand dictates human endeavor to explore and exploit new and innovative energy sources. As conventional oil and gas reserves deplete, we are constantly looking for newer sources for sustainable energy. Gas hydrates have long been discussed as the next big energy resource to the earth. Its global occurrence and vast quantity of natural gas stored is one of the main reasons for such interest in its study and exploration. Gas hydrates are solid crystalline substances with trapped molecules of gas inside cage-like crystals of water molecules. Gases such as methane, ethane, propane and carbon dioxide can form hydrates but in natural state, methane hydrates are the most common. Subsurface geological conditions with high pressure and low temperature favor the formation and stability of gas hydrates. While the occurrence and potential of gas hydrates as energy source has long been studied, there are still gaps in knowledge, especially in the quantitative research of gas hydrate formation and reservoir characterization. This study is focused on exploring and understanding the geological setting in which gas hydrates are formed and the subsequent changes in rock characteristics as they are deposited. It involves the numerical simulation of methane gas flow through fault to form hydrates. The models are representative of the subsurface geologic setting of Gulf of Mexico with a fault through layers of shale and sandstone. Hydrate formation simulated is of thermogenic origin. The simulations are conducted using TOUGH+HYDRATE, a numerical code developed at the Lawrence Berkley National Laboratory for modeling multiphase flow through porous medium. Simulation results predict that as the gas hydrates form in the pores of the model, the porosity, permeability and other rock properties are altered. Preliminary simulation results have shown that hydrates begin to form in the fault zone and gradually in the sandstone layers. The increase in hydrate

  8. Gender-specific health implications of minority stress among lesbians and gay men.

    Science.gov (United States)

    Bariola, Emily; Lyons, Anthony; Leonard, William

    2016-12-01

    Lesbians and gay men are exposed to unique minority stressors. We examined the health implications of one type of distal minority stressor (victimisation) and one type of proximal minority stressor (sexual identity concealment due to anticipated stigma) among lesbians and gay men. Gender-specific health implications were assessed. Data were collected via an online survey involving an Australian sample of 1,470 gay men and 1,264 lesbians. Survey questions assessed demographics, experiences of different forms of sexual identity-related victimisation and sexual identity concealment in a variety of contexts. Health outcomes included self-reported general health, illicit drug use, frequency of alcohol consumption, smoking status, and weight status. Gay men reported higher rates of victimisation and identity concealment than lesbians. Controlling for demographic differences, experiences of victimisation were associated with poorer self-rated health, illicit drug use, and smoking among both gay men and lesbians. In contrast, identity concealment was linked with poorer health outcomes among lesbians only. Our findings offer new insights into the potential antecedents of the health inequalities that have previously been reported for these populations. © 2016 Public Health Association of Australia.

  9. THCM Coupled Model for Hydrate-Bearing Sediments: Data Analysis and Design of New Field Experiments (Marine and Permafrost Settings)

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Marcelo J. [Texas A & M Univ., College Station, TX (United States); Santamarina, J. Carlos [King Abdullah Univ. of Science and Technology (Saudi Arabia)

    2017-02-14

    Gas hydrates are solid compounds made of water molecules clustered around low molecular weight gas molecules such as methane, hydrogen, and carbon dioxide. Methane hydrates form under pressure (P) and temperature (T) conditions that are common in sub-permafrost layers and in deep marine sediments. Stability conditions constrain the occurrence of gas hydrates to submarine sediments and permafrost regions. The amount of technically recoverable methane trapped in gas hydrate may exceed 104tcf. Gas hydrates are a potential energy resource, can contribute to climate change, and can cause large-scale seafloor instabilities. In addition, hydrate formation can be used for CO2 sequestration (also through CO2-CH4 replacement), and efficient geological storage seals. The experimental study of hydrate bearing sediments has been hindered by the very low solubility of methane in water (lab testing), and inherent sampling difficulties associated with depressurization and thermal changes during core extraction. This situation has prompted more decisive developments in numerical modeling in order to advance the current understanding of hydrate bearing sediments, and to investigate/optimize production strategies and implications. The goals of this research has been to addresses the complex thermo-hydro-chemo-mechanical THCM coupled phenomena in hydrate-bearing sediments, using a truly coupled numerical model that incorporates sound and proven constitutive relations, satisfies fundamental conservation principles. Analytical solutions aimed at verifying the proposed code have been proposed as well. These tools will allow to better analyze available data and to further enhance the current understanding of hydrate bearing sediments in view of future field experiments and the development of production technology.

  10. Depression and Associated Factors Among Gay and Heterosexual Male University Students in Nigeria.

    Science.gov (United States)

    Oginni, Olakunle A; Mosaku, Kolawole S; Mapayi, Boladale M; Akinsulore, Adesanmi; Afolabi, Temitope O

    2018-05-01

    Homosexuality is a recognized risk factor for depression in high-income countries; however, there is little research investigating the relationship between depression and sexual orientation in developing countries, especially in Africa. In this first study to investigate psychopathology in sexual minority men in Nigeria, the prevalence rates of depression in Nigerian gay and heterosexual individuals were compared as well as the explanatory power of risk and resilience factors in both groups. Eighty-one gay and 81 heterosexual male university students were, respectively, recruited from the Obafemi Awolowo University. Both groups were assessed for depression and other clinical factors, including alcohol and other substance use, suicidal ideation, and resilience. Gay students were further assessed for sexuality-related variables, including minority stress factors such as internalized homophobia and perceived stigma. The prevalence rates of depression among gay and heterosexual students were, respectively, 16 and 4.9% (OR 3.7; 95% CI 1.15-11.82), and this increased likelihood for depression was significantly attenuated by resilience. Clinical factors correlated significantly with depression in both groups, explaining 31% of the variance in depression in gay and heterosexual students, respectively. Sexuality-related variables including internalized homophobia and perceived stigma were further associated with depression in gay students-accounting for a further 14% of the variance of depression in gay students. The findings highlight the importance of minority stress factors in understanding depression among non-heterosexual individuals in a developing country, and the need for further research to investigate the mechanisms of these relationships in such settings.

  11. "Hedge Your Bets": Technology's Role in Young Gay Men's Relationship Challenges.

    Science.gov (United States)

    McKie, Raymond M; Milhausen, Robin R; Lachowsky, Nathan J

    2017-01-01

    Technology is playing an increasingly pervasive role among young gay men in the process of meeting potential romantic or sexual partners. We investigated challenges posed by technology related to young gay men's relationships. Focus groups (n = 9) of young gay men aged 18-24 (n = 43) were transcribed verbatim, and thematic analysis was used to identify two major themes regarding challenges to relationship development and maintenance. Subthemes include unrealistic expectations of relationships, inauthentic self-presentation online, sexual primacy over romance, increased opportunities for infidelity, and jealousy. The implications of this study for sexual education and sexual health promotion are discussed.

  12. Beyond Bright City Lights : The Migration Patterns of Gay Men and Lesbians

    OpenAIRE

    Wimark, Thomas

    2014-01-01

    One of the most persistent popular notions of gay men and lesbians is that they either live in or move to larger cities. In this thesis, the geography and migration paths of gay men and lesbians are studied using the life course perspective to challenge this idea. It is argued that gay men and lesbians are affected by the time and place into which they are born. Like heterosexuals, they are subject to the normative conceptions of life paths that are present at a specific historical period and...

  13. Bibliotherapy for Gay and Lesbian Youth: Overcoming the Structure of Silence

    Science.gov (United States)

    Vare, Jonatha W.; Norton, Terry L.

    2004-01-01

    Gay and lesbian youth encounter most of the typical biological and cognitive changes of adolescence. However, cultural circumstances create differences in the social and emotional development of many gay and lesbian teens. In the United States, these teens often live within social environments characterized by a hostile fear and an active…

  14. Trends in Canadian Newspaper Coverage of Gay-Straight Alliances, 2000-2009

    Science.gov (United States)

    Herriot, Lindsay

    2011-01-01

    Gay-straight alliances (GSAs) in Canadian public schools have gained considerable attention from print media since reports first surfaced in the year 2000. This study tracked and analyzed Canadian newspaper reporting about GSA creation. It summarized the shift in public opinion toward lesbian, gay, bisexual, transgender, and queer (LGBTQ) youth…

  15. In-situ study of the thermal properties of hydrate slurry by high pressure DSC

    Energy Technology Data Exchange (ETDEWEB)

    Sari, O.; Hu, J.; Brun, F.; Erbeau, N. [Institute of Thermal Engineering, University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Homsy, P. [Nestec, Vevey (Switzerland); Logel, J.-C. [Axima Refrigeration, Bischheim (France)

    2008-07-01

    Knowing the enthalpy of hydrate slurry is very essential for energy balance and industrial applications. No direct measurement processes had been developed in this field in the past time. A new experimental method with special device has been developed to carry out on-line measurement of the thermal properties for hydrate slurry under dynamic conditions. With this special device, it is possible to deliver the hydrate slurry to the high pressure DSC (Differential Scanning Calorimetry) directly from the production tank or pipes. Thermal data acquisition will be performed afterwards by DSC. The investigated conditions were at pressure of 30 bar and temperature of {approx}+7 {sup o}C. The dissociation enthalpy of CO{sub 2} hydrate slurry was about 54 kJ/kg, corresponding 10.8% of solid fraction. The on-line measurement results for CO{sub 2} hydrate slurry give a good tendency to apply this phase change slurry to the industrial refrigeration process. (author)

  16. Seismic reflections associated with submarine gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Andreassen, K

    1996-12-31

    Gas hydrates are often suggested as a future energy resource. This doctoral thesis improves the understanding of the concentration and distribution of natural submarine gas hydrates. The presence of these hydrates are commonly inferred from strong bottom simulating reflection (BSR). To investigate the nature of BSR, this work uses seismic studies of hydrate-related BSRs at two different locations, one where gas hydrates are accepted to exist and interpreted to be very extensive (in the Beaufort Sea), the other with good velocity data and downhole logs available (offshore Oregon). To ascertain the presence of free gas under the BSR, prestack offset data must supplement near-vertical incidence seismic data. A tentative model for physical properties of sediments partially saturated with gas hydrate and free gas is presented. This model, together with drilling information and seismic data containing the BSR beneath the Oregon margin and the Beaufort Sea, made it possible to better understand when to apply the amplitude-versus-offset (AVO) method to constrain BSR gas hydrate and gas models. Distribution of natural gas hydrates offshore Norway and Svalbard is discussed and interpreted as reflections from the base of gas hydrate-bearing sediments, overlying sediments containing free gas. Gas hydrates inferred to exist at the Norwegian-Svalbard continental margin correlate well with Cenozoic depocenters, and the associated gas is assumed to be mainly biogenic. Parts of that margin have a high potential for natural gas hydrates of both biogenic and thermogenic origin. 235 refs., 86 figs., 4 tabs.

  17. Seismic reflections associated with submarine gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Andreassen, K.

    1995-12-31

    Gas hydrates are often suggested as a future energy resource. This doctoral thesis improves the understanding of the concentration and distribution of natural submarine gas hydrates. The presence of these hydrates are commonly inferred from strong bottom simulating reflection (BSR). To investigate the nature of BSR, this work uses seismic studies of hydrate-related BSRs at two different locations, one where gas hydrates are accepted to exist and interpreted to be very extensive (in the Beaufort Sea), the other with good velocity data and downhole logs available (offshore Oregon). To ascertain the presence of free gas under the BSR, prestack offset data must supplement near-vertical incidence seismic data. A tentative model for physical properties of sediments partially saturated with gas hydrate and free gas is presented. This model, together with drilling information and seismic data containing the BSR beneath the Oregon margin and the Beaufort Sea, made it possible to better understand when to apply the amplitude-versus-offset (AVO) method to constrain BSR gas hydrate and gas models. Distribution of natural gas hydrates offshore Norway and Svalbard is discussed and interpreted as reflections from the base of gas hydrate-bearing sediments, overlying sediments containing free gas. Gas hydrates inferred to exist at the Norwegian-Svalbard continental margin correlate well with Cenozoic depocenters, and the associated gas is assumed to be mainly biogenic. Parts of that margin have a high potential for natural gas hydrates of both biogenic and thermogenic origin. 235 refs., 86 figs., 4 tabs.

  18. The Intersection of Gay and Christian Identities on Christian College Campuses

    Science.gov (United States)

    Wentz, Joel M.; Wessel, Roger D.

    2011-01-01

    Because some Christian colleges prohibit same-sex sexual behaviors, the development of authentic sexual identities on these campuses may be difficult for gay and lesbian students. This article introduces the idea of an identity conflict that may occur between sexual and spiritual identities for gay and lesbian students at Christian colleges and…

  19. Gas Hydrate Storage of Natural Gas

    Energy Technology Data Exchange (ETDEWEB)

    Rudy Rogers; John Etheridge

    2006-03-31

    Environmental and economic benefits could accrue from a safe, above-ground, natural-gas storage process allowing electric power plants to utilize natural gas for peak load demands; numerous other applications of a gas storage process exist. A laboratory study conducted in 1999 to determine the feasibility of a gas-hydrates storage process looked promising. The subsequent scale-up of the process was designed to preserve important features of the laboratory apparatus: (1) symmetry of hydrate accumulation, (2) favorable surface area to volume ratio, (3) heat exchanger surfaces serving as hydrate adsorption surfaces, (4) refrigeration system to remove heat liberated from bulk hydrate formation, (5) rapid hydrate formation in a non-stirred system, (6) hydrate self-packing, and (7) heat-exchanger/adsorption plates serving dual purposes to add or extract energy for hydrate formation or decomposition. The hydrate formation/storage/decomposition Proof-of-Concept (POC) pressure vessel and supporting equipment were designed, constructed, and tested. This final report details the design of the scaled POC gas-hydrate storage process, some comments on its fabrication and installation, checkout of the equipment, procedures for conducting the experimental tests, and the test results. The design, construction, and installation of the equipment were on budget target, as was the tests that were subsequently conducted. The budget proposed was met. The primary goal of storing 5000-scf of natural gas in the gas hydrates was exceeded in the final test, as 5289-scf of gas storage was achieved in 54.33 hours. After this 54.33-hour period, as pressure in the formation vessel declined, additional gas went into the hydrates until equilibrium pressure/temperature was reached, so that ultimately more than the 5289-scf storage was achieved. The time required to store the 5000-scf (48.1 hours of operating time) was longer than designed. The lower gas hydrate formation rate is attributed to a

  20. Distinguishing between hydrated, partially hydrated or unhydrated clinker in hardened concrete using microscopy

    NARCIS (Netherlands)

    Valcke, S.L.A.; Rooij, M.R. de; Visser, J.H.M.; Nijland, T.G.

    2010-01-01

    Hydration of clinker particles is since long a topic of interest in both designing and optimizing cement composition and its quantity used in concrete. The interest for carefully observing and also quantifying the type or stage of clinker hydration in hardened cement paste is twofold. Firstly, the

  1. Hydration characteristics of zirconium oxide replaced Portland cement for use as a root-end filling material.

    Science.gov (United States)

    Camilleri, J; Cutajar, A; Mallia, B

    2011-08-01

    Zirconium oxide can be added to dental materials rendering them sufficiently radiopaque. It can thus be used to replace the bismuth oxide in mineral trioxide aggregate (MTA). Replacement of Portland cement with 30% zirconium oxide mixed at a water/cement ratio of 0.3 resulted in a material with adequate physical properties. This study aimed at investigating the microstructure, pH and leaching in physiological solution of Portland cement replaced zirconium oxide at either water-powder or water-cement ratios of 0.3 for use as a root-end filling material. The hydration characteristics of the materials which exhibited optimal behavior were evaluated. Portland cement replaced by zirconium oxide in varying amounts ranging from 0 to 50% in increments of 10 was prepared and divided into two sets. One set was prepared at a constant water/cement ratio while the other set at a constant water/powder ratio of 0.3. Portland cement and MTA were used as controls. The materials were analyzed under the scanning electron microscope (SEM) and the hydration products were determined. X-ray energy dispersive analysis (EDX) was used to analyze the elemental composition of the hydration products. The pH and the amount of leachate in Hank's balanced salt solution (HBSS) were evaluated. A material that had optimal properties that satisfied set criteria and could replace MTA was selected. The microstructure of the prototype material and Portland cement used as a control was assessed after 30 days using SEM and atomic ratio diagrams of Al/Ca versus Si/Ca and S/Ca versus Al/Ca were plotted. The hydration products of Portland cement replaced with 30% zirconium oxide mixed at water/cement ratio of 0.3 were calcium silicate hydrate, calcium hydroxide and minimal amounts of ettringite and monosulphate. The calcium hydroxide leached in HBSS solution resulted in an increase in the pH value. The zirconium oxide acted as inert filler and exhibited no reaction with the hydration by-products of Portland

  2. Cultural investment: providing opportunities to reduce risky behavior among gay American Indian males.

    Science.gov (United States)

    Gilley, Brian Joseph; Co-Cké, John Hawk

    2005-09-01

    Many gay American Indian (GAI) men feel alienated from their tribal, ceremonial and social communities because of homophobia and heterosexism. As a result, they often turn to their local gay community for social participation and sex opportunities. It is no secret that a significant aspect of some gay communities is socializing in local bars and clubs. The gay bar scene makes healthy living difficult for Native American gay men. This is especially the case for those who are in alcohol or drug recovery. In response, gay Native men's support groups are attempting to make available a cultural alternative to the double bind of alienation from one's Native community and exposure to substance abuse by providing alcohol and substance free opportunities for ceremonial and social involvement. The hope is that the men will go to bars less frequently and instead turn to Native cultural activities in men's groups for social, spiritual and emotional support. The logic of this approach assumes that individuals who are culturally invested in a community will gain a level of self and social acceptance, making them less likely to abuse substances and put themselves at risk for HIV infection. The information presented in this article comes from over six years of ethnographic research among GAI men concerning self and social acceptance, HIV/AIDS and American Indian GLBT identity.

  3. Low-δD hydration rinds in Yellowstone perlites record rapid syneruptive hydration during glacial and interglacial conditions

    Science.gov (United States)

    Bindeman, Ilya N.; Lowenstern, Jacob B.

    2016-01-01

    Hydration of silicic volcanic glass forms perlite, a dusky, porous form of altered glass characterized by abundant “onion-skin” fractures. The timing and temperature of perlite formation are enigmatic and could plausibly occur during eruption, during post-eruptive cooling, or much later at ambient temperatures. To learn more about the origin of natural perlite, and to fingerprint the hydration waters, we investigated perlitic glass from several synglacial and interglacial rhyolitic lavas and tuffs from the Yellowstone volcanic system. Perlitic cores are surrounded by a series of conchoidal cracks that separate 30- to 100-µm-thick slivers, likely formed in response to hydration-induced stress. H2O and D/H profiles confirm that most D/H exchange happens together with rapid H2O addition but some smoother D/H variations may suggest separate minor exchange by deuterium atom interdiffusion following hydration. The hydrated rinds (2–3 wt% H2O) transition rapidly (within 30 µm, or by 1 wt% H2O per 10 µm) to unhydrated glass cores. This is consistent with quenched “hydration fronts” where H2O diffusion coefficients are strongly dependent on H2O concentrations. The chemical, δ18O, and δD systematics of bulk glass records last equilibrium between ~110 and 60 °C without chemical exchange but with some δ18O exchange. Similarly, the δ18O of water extracted from glass by rapid heating suggests that water was added to the glass during cooling at higher rates of diffusion at 60–110 °C temperatures, compared with values expected from extrapolation of high-temperature (>400 °C) experimental data. The thick hydration rinds in perlites, measuring hundreds of microns, preserve the original D/H values of hydrating water as a recorder of paleoclimate conditions. Measured δD values in perlitic lavas are −150 to −191 or 20–40 ‰ lower than glass hydrated by modern Yellowstone waters. This suggests that Yellowstone perlites record the low-δD signature

  4. Growth of a Hydrate Mound in the Sea of Japan over 300 ka as Revealed by U-Th Ages of MDAC and by H2S Concentrations of Massive Hydrates

    Science.gov (United States)

    Matsumoto, R.; Snyder, G. T.; Hiruta, A.; Kakizaki, Y.; Huang, C. Y.; Shen, C. C.

    2017-12-01

    The geological and geophysical exploration of gas hydrate in the Sea of Japan has revealed that hydrates occur as thick massive deposits within gas chimneys which often give rise to pingo-like hydrate mounds on the seafloor. We examine one case in which LWD has demonstrated anomalous profiles including both very low natural gamma ray (<10 API) and high acoustic velocities (2.5 to 3.5 km/s) extending down to 120mbsf, the base of gas hydrate stability (BGHS)[1]. Both conventional and pressure coring have confirmed thick, massive deposits of pure-gas hydrates. Hydrates in the shallow subsurface (< 20mbsf) are characterized by high H2S concentrations corresponding to AOM-induced production of HS-. The deeper hydrates generally have negligible amounts of H2S, with occasional exceptions in which H2S is moderately high. These observations lead us to conclude that both the re-equilibration and growth of hydrates in high CH4 and low to zero H2S conditions has continued during burial, and that this ongoing growth is an essential processes involved in the development of massive hydrates in the Sea of Japan.Regardless of depth, the Japan Sea gas hydrates are closely associated with 13-C depleted, methane-derived authigenic carbonates (MDACs). These MDACs are considered to have been formed at near-SMT depths as a response to increased alkalinity caused by AOM and, as such, MDACs are assumed to represent approximate paleo-seafloor at times of enhanced methane flux and intensive accumulation of gas hydrate in shallow subsurface. U-Th ages of MDACs collected from various depths in a mound-chimney system in central Joetsu Spur have revealed that the paleo-seafloor of 300 ka is presently situated at 30 to 55 mbsf within the gas chimney, in contrast to off-mound sites where it is situated at 100 mbsf. This suggests that at 300 ka the mound stood as a "hydrate-pingo" of 70 m high relative to the surrounding sea floor. At this time, the BGHS shoaled upwards 10m due to eustatic sea

  5. Individualism-collectivism, self-efficacy, and other factors associated with risk taking among gay Asian and Caucasian men.

    Science.gov (United States)

    Mao, Limin; Van de Ven, Paul; McCormick, John

    2004-02-01

    A theoretical framework, which included perspectives of individualism-collectivism and self-efficacy, was used to investigate factors associated with sexual risk practice among gay Asian and Caucasian men. "Risk" was defined as unprotected anal intercourse with any casual partner or with a regular partner whose HIV status was not concordant with the participant's. Altogether, 201 Caucasian and 199 Asian gay men, largely recruited from gay social venues in inner Sydney, completed an anonymous questionnaire. Most participants were gay self-identified and gay community attached, and more than half of the Asian men had been living in Sydney for at least 3 years. Overall, the Asian men were more collectivist oriented and the Caucasian men more individualist oriented. Data analyses revealed that higher self-efficacy in avoiding casual risk encounters and smaller proportion of gay friends were associated with less risk. The inclusion of individualism-collectivism and social cognitive variables in the examination of sexual risk practices among gay men from different cultural backgrounds holds promise.

  6. A Program Review of a Middle School Gay-Straight Alliance Club

    Science.gov (United States)

    Quasha, Scott; McCabe, Paul C.; Ortiz, Samuel O.

    2014-01-01

    This program review examined a middle school Gay-Straight Alliance (GSA) club within a northeastern suburban school situated in a large metropolitan area. The GSA was the first in the region to start exclusively in a standalone middle school. The review was accomplished through a staff survey comparing school climates for lesbian, gay, bisexual,…

  7. Methane Hydrate Pellet Transport Using the Self-Preservation Effect: A Techno-Economic Analysis

    Directory of Open Access Journals (Sweden)

    Hans Osterkamp

    2012-07-01

    Full Text Available Within the German integrated project SUGAR, aiming for the development of new technologies for the exploration and exploitation of submarine gas hydrates, the option of gas transport by gas hydrate pellets has been comprehensively re-investigated. A series of pVT dissociation experiments, combined with analytical tools such as x-ray diffraction and cryo-SEM, were used to gather an additional level of understanding on effects controlling ice formation. Based on these new findings and the accessible literature, knowns and unknowns of the self-preservation effect important for the technology are summarized. A conceptual process design for methane hydrate production and pelletisation has been developed. For the major steps identified, comprising (i hydrate formation; (ii dewatering; (iii pelletisation; (iv pellet cooling; and (v pressure relief, available technologies have been evaluated, and modifications and amendments included where needed. A hydrate carrier has been designed, featuring amongst other technical solutions a pivoted cargo system with the potential to mitigate sintering, an actively cooled containment and cargo distribution system, and a dual fuel engine allowing the use of the boil-off gas. The design was constrained by the properties of gas hydrate pellets, the expected operation on continental slopes in areas with rough seas, a scenario-defined loading capacity of 20,000 m3 methane hydrate pellets, and safety as well as environmental considerations. A risk analysis for the transport at sea has been carried out in this early stage of development, and the safety level of the new concept was compared to the safety level of other ship types with similar scopes, i.e., LNG carriers and crude oil tankers. Based on the results of the technological part of this study, and with best knowledge available on the alternative technologies, i.e., pipeline, LNG and CNG transportation, an evaluation of the economic

  8. Identity management strategies among HIV-positive Colombian gay men in London.

    Science.gov (United States)

    Jaspal, Rusi; Williamson, Iain

    2017-12-01

    This study set out to explore the social-psychological aspects of living with HIV among a group of HIV-positive Colombian gay men in London, and the strategies that they deployed to manage ensuing threats to their identities. Focus group and individual interview data were collected from 14 Colombian gay men living with HIV, and were analysed using qualitative thematic analysis and identity process theory. The following themes are discussed: (1) identity struggles and conflicts in Colombia, (2), managing multiple layers of social stigma in England, and (3) changing interpersonal and intergroup dynamics, which highlight the inter-connections between sexual prejudice, sexual risk-taking and HIV stigma. Identity may be chronically threatened due to the multiple layers of stigma, which can limit the coping strategies available to individuals. Findings strongly support the need for action and programmes to highlight and tackle both racism and HIV stigma on the gay scene and to fund more specific resources for sub-communities of gay, bisexual and other men who have sex with men, which employ appropriately trained and culturally competent staff.

  9. THERMODYNAMIC MODEL OF GAS HYDRATES

    OpenAIRE

    Недоступ, В. И.; Недоступ, О. В.

    2015-01-01

    The interest to gas hydrates grows last years. Therefore working out of reliable settlement-theoretical methods of definition of their properties is necessary. The thermodynamic model of gas hydrates in which the central place occupies a behaviour of guest molecule in cell is described. The equations of interaction of molecule hydrate formative gas with cell are received, and also an enthalpy and energy of output of molecule from a cell are determined. The equation for calculation of thermody...

  10. Gas hydrate cool storage system

    Science.gov (United States)

    Ternes, M.P.; Kedl, R.J.

    1984-09-12

    The invention presented relates to the development of a process utilizing a gas hydrate as a cool storage medium for alleviating electric load demands during peak usage periods. Several objectives of the invention are mentioned concerning the formation of the gas hydrate as storage material in a thermal energy storage system within a heat pump cycle system. The gas hydrate was formed using a refrigerant in water and an example with R-12 refrigerant is included. (BCS)

  11. Indian National Gas Hydrate Program Expedition 01 report

    Science.gov (United States)

    Collett, Timothy S.; Riedel, M.; Boswell, R.; Presley, J.; Kumar, P.; Sathe, A.; Sethi, A.; Lall, M.V.; ,

    2015-01-01

    Gas hydrate is a naturally occurring “ice-like” combination of natural gas and water that has the potential to serve as an immense resource of natural gas from the world’s oceans and polar regions. However, gas-hydrate recovery is both a scientific and a technical challenge and much remains to be learned about the geologic, engineering, and economic factors controlling the ultimate energy resource potential of gas hydrate. The amount of natural gas contained in the world’s gas-hydrate accumulations is enormous, but these estimates are speculative and range over three orders of magnitude from about 2,800 to 8,000,000 trillion cubic meters of gas. By comparison, conventional natural gas accumulations (reserves and undiscovered, technically recoverable resources) for the world are estimated at approximately 440 trillion cubic meters. Gas recovery from gas hydrate is hindered because the gas is in a solid form and because gas hydrate commonly occurs in remote Arctic and deep marine environments. Proposed methods of gas recovery from gas hydrate generally deal with disassociating or “melting” in situ gas hydrate by heating the reservoir beyond the temperature of gas-hydrate formation, or decreasing the reservoir pressure below hydrate equilibrium. The pace of energy-related gas hydrate assessment projects has accelerated over the past several years.

  12. Anti-Agglomerator of Tetra-n-Butyl Ammonium Bromide Hydrate and Its Effect on Hydrate-Based CO2 Capture

    Directory of Open Access Journals (Sweden)

    Rong Li

    2018-02-01

    Full Text Available Tetra-n-butyl ammonium bromide (TBAB was widely used in the research fields of cold storage and CO2 hydrate separation due to its high phase change latent heat and thermodynamic promotion for hydrate formation. Agglomeration always occurred in the process of TBAB hydrate generation, which led to the blockage in the pipeline and the separation apparatus. In this work, we screened out a kind of anti-agglomerant that can effectively solve the problem of TBAB hydrate agglomeration. The anti-agglomerant (AA is composed of 90% cocamidopropyl dimethylamine and 10% glycerol, which can keep TBAB hydrate of 19.3–29.0 wt. % in a stable state of slurry over 72 h. The microscopic observation of the morphology of the TBAB hydrate particles showed that the addition of AA can greatly reduce the size of the TBAB hydrate particles. CO2 gas separation experiments found that the addition of AA led to great improvement on gas storage capacity, CO2 split fraction and separation factor, due to the increasing of contact area between gas phase and hydrate particles. The CO2 split fraction and separation factor with AA addition reached up to 70.3% and 42.8%, respectively.

  13. Political science. When contact changes minds: an experiment on transmission of support for gay equality.

    Science.gov (United States)

    LaCour, Michael J; Green, Donald P

    2014-12-12

    Can a single conversation change minds on divisive social issues, such as same-sex marriage? A randomized placebo-controlled trial assessed whether gay (n = 22) or straight (n = 19) messengers were effective at encouraging voters (n = 972) to support same-sex marriage and whether attitude change persisted and spread to others in voters' social networks. The results, measured by an unrelated panel survey, show that both gay and straight canvassers produced large effects initially, but only gay canvassers' effects persisted in 3-week, 6-week, and 9-month follow-ups. We also find strong evidence of within-household transmission of opinion change, but only in the wake of conversations with gay canvassers. Contact with gay canvassers further caused substantial change in the ratings of gay men and lesbians more generally. These large, persistent, and contagious effects were confirmed by a follow-up experiment. Contact with minorities coupled with discussion of issues pertinent to them is capable of producing a cascade of opinion change. Copyright © 2014, American Association for the Advancement of Science.

  14. Comparative morality judgments about lesbians and gay men teaching and adopting children.

    Science.gov (United States)

    Kirby, Brenda J; Michaelson, Christina

    2015-01-01

    The purpose of this study was to compare morality judgments of American Catholics and the general public about lesbians and gay men adopting and teaching children. The general sample endorsed higher agreement that lesbians and gay men should be allowed to adopt and to teach children compared to the Catholic only sample. Older participants were less accepting than all other age groups, and there was an interaction effect between education and political ideology such that those with less education and with more politically conservative beliefs were generally less accepting of lesbians and gay men adopting and teaching children.

  15. 76 FR 44317 - Gay & Robinson, Inc.; Notice of Declaration of Intention and Soliciting Comments, Protests, and...

    Science.gov (United States)

    2011-07-25

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. DI11-12-000] Gay & Robinson... Filed: July 11, 2011. d. Applicant: Gay & Robinson, Inc. e. Name of Project: Olokele River Hydroelectric... Contact: Charles Okamoto, President, Gay & Robinson, Inc., P.O. Box 156, Kaumakani, Hawaii 96747...

  16. 76 FR 51024 - Gay & Robinson, Inc.; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

    Science.gov (United States)

    2011-08-17

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [ Project No. 14219-000] Gay & Robinson... Intervene, and Competing Applications On July 1, 2011, Gay & Robinson, Inc., filed an application for a.... Applicant Contact: Mr. Charles Okamoto, President, Gay & Robinson, Inc., P.O. Box 156, Kaumakani, Hawaii...

  17. Straight until proven gay: A systematic bias toward straight categorizations in sexual orientation judgments.

    Science.gov (United States)

    Lick, David J; Johnson, Kerri L

    2016-06-01

    Perceivers achieve above chance accuracy judging others' sexual orientations, but they also exhibit a notable response bias by categorizing most targets as straight rather than gay. Although a straight categorization bias is evident in many published reports, it has never been the focus of systematic inquiry. The current studies therefore document this bias and test the mechanisms that produce it. Studies 1-3 revealed the straight categorization bias cannot be explained entirely by perceivers' attempts to match categorizations to the number of gay targets in a stimulus set. Although perceivers were somewhat sensitive to base rate information, their tendency to categorize targets as straight persisted when they believed each target had a 50% chance of being gay (Study 1), received explicit information about the base rate of gay targets in a stimulus set (Study 2), and encountered stimulus sets with varying base rates of gay targets (Study 3). The remaining studies tested an alternate mechanism for the bias based upon perceivers' use of gender heuristics when judging sexual orientation. Specifically, Study 4 revealed the range of gendered cues compelling gay judgments is smaller than the range of gendered cues compelling straight judgments despite participants' acknowledgment of equal base rates for gay and straight targets. Study 5 highlighted perceptual experience as a cause of this imbalance: Exposing perceivers to hyper-gendered faces (e.g., masculine men) expanded the range of gendered cues compelling gay categorizations. Study 6 linked this observation to our initial studies by demonstrating that visual exposure to hyper-gendered faces reduced the magnitude of the straight categorization bias. Collectively, these studies provide systematic evidence of a response bias in sexual orientation categorization and offer new insights into the mechanisms that produce it. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  18. A Gay Immigrant Student's Perspective: Unspeakable Acts in the Language Class

    Science.gov (United States)

    Nelson, Cynthia D.

    2010-01-01

    This article focuses on a subset of the student cohort that has, until recently, been largely hidden from view in the literature of language education: gay immigrants. Little is known about what sorts of classroom experiences gay immigrant students find engaging or alienating, or why this sort of knowledge is needed. This case study uses interview…

  19. Effect of hydrated apple powder on dough rheology and cookies quality

    Directory of Open Access Journals (Sweden)

    Michaela Lauková

    2016-10-01

    Full Text Available Dietary fiber is a group of food components, which are resistant to human enzymatic digestion. The incorporation of dietary fiber obtained from various sources of fruit and vegetable by-products into the cereal based products such as bread, rolls, cookies, muffins, crackers, cakes and pasta is of growing interest for the food industry. The replacement of wheat flour by dietary fiber from various sources can change physicochemical, textural and organoleptic characteristic of bakery products. Apple pomace is the main by-product produced in the apple fruit processing industry. It is a rich source of carbohydrate, pectin, crude fiber, and minerals. The dietary fiber content in apple pomace ranges between 33 - 35%. The influence of hydrated commercial dietary fiber on wheat dough rheology (5, 10 and 15% flour replacement and physical and sensory properties of cookies was examined. It was found that addition of HAP significantly increased the rheological properties of dough such as water absorption (from 58.0% to 75.3%, dough stability (from 6.7 min to 11.6 min and prolonged dough development time (from 3.5 min to 11.0 min and reduced the mixing tolerance index (from 34.7 BU to 11.9 BU. It was also concluded that hydrated apple powder addition reduced physical properties of cookies such as volume (from 10.4 cm3 to 8.0 cm3, diameter (from 4.7 cm to 4.2 cm, volume index (from 1.35 cm to 1.10 cm and porosity (from 0.32 to 0.24. Sensory properties (taste, odour, stickiness, firmness and density of cookies were also analysed. Cookies with addition of hydrated apple powder had fruity taste and odour and showed high overall acceptance. From this study resulted that hydrated apple powder can be used as potentially source of dietary fiber in cookie formulation. Moreover, addition of apple pomace inhibits the use of any other flavouring ingredients because has a pleasant fruity flavour.

  20. Attributions for sexual orientation vs. stereotypes : How beliefs about value violations account for attribution effects on anti-gay discrimination

    NARCIS (Netherlands)

    Reyna, Christine; Wetherell, Geoffrey; Yantis, Caitlyn; Brandt, Mark J.

    Attributions for sexual orientation strongly predict opposition to gay rights policies; however, we propose that beliefs that gays and lesbians violate important values drive gay rights opposition and account for the relationship between attributions and anti-gay discrimination. In two studies, we

  1. Gayspeak: Gay Male & Lesbian Communication.

    Science.gov (United States)

    Chesebro, James W., Ed.

    In a departure from previous statistical studies, this book focuses on the social responses to homosexuality rather than on homosexual behavior itself. The essays in the book maintain that communication--how gay men and lesbians relate to one another as well as to heterosexuals--is the major factor that determines public opinion about…

  2. FY1995 molecular control technology for mining of methane-gas-hydrate; 1995 nendo methane hydrate no bunshi seigyo mining

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The objectives of the investigation are as follows: 1) developing a method to control formation/dissociation of methane-gas-hydrate, 2) developing a technology to displace methane gas by CO{sub 2} in methane-gas-hydrate deposit, 3) developing a technology to produce methane gas from the deposit efficiently. The final purpose of the project is to create new mining industry that solves both the problems of energy and global environment. 1) Clustering of water molecules is found to play the key role in the methane gas hydrate formation. 2) Equilibrium properties and kinetics of gas hydrates formation and dissociation in bulk-scale gas-hydrate are clarified in the practical environmental conditions. 3) Particle size of hydrate deposit influences the formation and dissociation of bulk-scale gas-hydrate crystal. 4) Mass transfer between gas and liquid phase in turbulent bubbly flow is a function of bubble diameter. The mass transfer depends on interfacial dynamics. (NEDO)

  3. Changes in structure and preferential cage occupancy of ethane hydrate and ethane-methane mixed gas hydrate under high pressure

    International Nuclear Information System (INIS)

    Hirai, H; Takahara, N; Kawamura, T; Yamamoto, Y; Yagi, T

    2010-01-01

    Structural changes and preferential cage occupancies were examined for ethane hydrate and ethane-methane mixed gas hydrates with five compositions in a pressure range of 0.2 to 2.8 GPa at room temperature. X-ray diffractometry and Raman spectroscopy showed the following structural changes. The initial structure, structure I (sI), of ethane hydrate was retained up to 2.1 GPa without any structural change. For the mixed hydrates, sI was widely distributed throughout the region examined except for the methane-rich and lower pressure regions, where sII and sH appeared. Above 2.1 GPa ethane hydrate and all of the mixed hydrates decomposed into ice VI and ethane fluid or methane-ethane fluid, respectively. The Raman study revealed that occupation of the small cages by ethane molecules occurred above 0.1 GPa in ethane hydrate and continued up to decomposition at 2.1 GPa, although it was thought that ethane molecules were contained only in the large cage.

  4. PRODUCTION OF HYDRATED ELECTRONS FROM PHOTOIONIZATION OF DISSOLVED ORGANIC MATTER IN NATURAL WATERS

    Science.gov (United States)

    Under UV irradiation, an important primary photochemical reaction of colored dissolved organic matter (CDOM) is electron ejection, producing hydrated electrons (e-aq). The efficiency of this process has been studied in both fresh and seawater samples with both steady-state scave...

  5. Friends with benefits, but without the sex: straight women and gay men exchange trustworthy mating advice.

    Science.gov (United States)

    Russell, Eric M; DelPriore, Danielle J; Butterfield, Max E; Hill, Sarah E

    2013-02-09

    Although research has made progress in elucidating the benefits exchanged within same- and opposite-sex friendships formed between heterosexual men and women, it is less clear why straight women and gay men form close relationships with one another. The current experiments begin to address this question by exploring a potential benefit hypothesized to be uniquely available to straight women and gay men in the context of these friendships: trustworthy mating advice. Experiment 1 revealed that straight women perceive mating-relevant advice from a gay man to be more trustworthy than similar advice offered by a straight man or woman. Experiment 2 demonstrated that gay men perceive mating advice offered by a straight woman to be more trustworthy than advice offered by a lesbian woman or another gay man. Overall, the results provide initial experimental evidence that relationships between gay men and straight women may be characterized by a mutual exchange of mating-relevant benefits in the absence of sexual interest or competition.

  6. Friends with Benefits, but without the Sex: Straight Women and Gay Men Exchange Trustworthy Mating Advice

    Directory of Open Access Journals (Sweden)

    Eric M. Russell

    2013-01-01

    Full Text Available Although research has made progress in elucidating the benefits exchanged within same- and opposite-sex friendships formed between heterosexual men and women, it is less clear why straight women and gay men form close relationships with one another. The current experiments begin to address this question by exploring a potential benefit hypothesized to be uniquely available to straight women and gay men in the context of these friendships: trustworthy mating advice. Experiment 1 revealed that straight women perceive mating-relevant advice from a gay man to be more trustworthy than similar advice offered by a straight man or woman. Experiment 2 demonstrated that gay men perceive mating advice offered by a straight woman to be more trustworthy than advice offered by a lesbian woman or another gay man. Overall, the results provide initial experimental evidence that relationships between gay men and straight women may be characterized by a mutual exchange of mating-relevant benefits in the absence of sexual interest or competition.

  7. QUEM DISSE BERENICE, QUE SER GAY É SER UM BOM VENDEDOR DE LOJAS DE SHOPPING?

    Directory of Open Access Journals (Sweden)

    Natacha Secco Santos

    2017-12-01

    Full Text Available Este trabalho tem como intuito compreender o padrão normativo da contratação de gays em lojas de shopping. Para isso, a contratação na percepção contratantes e dos contratados gays é analisada a partir das categorias de análise: físico, cognitivo, material, representacional e seus atributos em comum na contratação de funcionários gays. Foram entrevistados cinco contratantes e seis contratados de lojas de um shopping de Maringá. Os resultados encontrados mostram que, contratantes são instruídos e enxergam a necessidade de contratar vendedores gays, mas priorizam pelo perfil heteronormativo. Conclui-se que existe discriminação na contratação de gays e um padrão comportamental exigido pelas organizações.

  8. The impact of zirconium oxide radiopacifier on the early hydration behaviour of white Portland cement

    International Nuclear Information System (INIS)

    Coleman, Nichola J.; Li, Qiu

    2013-01-01

    Zirconium oxide has been identified as a candidate radiopacifying agent for use in Portland cement-based biomaterials. During this study, the impact of 20 wt.% zirconium oxide on the hydration and setting reactions of white Portland cement (WPC) was monitored by powder X-ray diffraction (XRD), 29 Si and 27 Al magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR), transmission electron microscopy (TEM) and Vicat apparatus. The presence of 20 wt.% zirconium oxide particles in the size-range of 0.2 to 5 μm was found to reduce the initial and final setting times of WPC from 172 to 147 min and 213 to 191 min, respectively. Zirconium oxide did not formally participate in the chemical reactions of the hydrating cement; however, the surface of the zirconium oxide particles presented heterogeneous nucleation sites for the precipitation and growth of the early C-S-H gel products which accelerated the initial setting reactions. The presence of zirconium oxide was found to have little impact on the development of the calcium (sulpho)aluminate hydrate phases. - Highlights: ► This is the first study of Portland cement-based biomaterials by 27 Al and 29 Si NMR. ► 20 wt.% ZrO 2 radiopacifier accelerates the early cement hydration reactions. ► Extent of hydration after 6 h is increased from 5.7% to 15% in the presence of ZrO 2 . ► Initial and final setting times are reduced by 25 and 22 min, respectively. ► ZrO 2 provides nucleation sites for the precipitation of early hydration products.

  9. Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Overview of scientific and technical program

    Science.gov (United States)

    Hunter, R.B.; Collett, T.S.; Boswell, R.; Anderson, B.J.; Digert, S.A.; Pospisil, G.; Baker, R.; Weeks, M.

    2011-01-01

    The Mount Elbert Gas Hydrate Stratigraphic Test Well was drilled within the Alaska North Slope (ANS) Milne Point Unit (MPU) from February 3 to 19, 2007. The well was conducted as part of a Cooperative Research Agreement (CRA) project co-sponsored since 2001 by BP Exploration (Alaska), Inc. (BPXA) and the U.S. Department of Energy (DOE) in collaboration with the U.S. Geological Survey (USGS) to help determine whether ANS gas hydrate can become a technically and commercially viable gas resource. Early in the effort, regional reservoir characterization and reservoir simulation modeling studies indicated that up to 0.34 trillion cubic meters (tcm; 12 trillion cubic feet, tcf) gas may be technically recoverable from 0.92 tcm (33 tcf) gas-in-place within the Eileen gas hydrate accumulation near industry infrastructure within ANS MPU, Prudhoe Bay Unit (PBU), and Kuparuk River Unit (KRU) areas. To further constrain these estimates and to enable the selection of a test site for further data acquisition, the USGS reprocessed and interpreted MPU 3D seismic data provided by BPXA to delineate 14 prospects containing significant highly-saturated gas hydrate-bearing sand reservoirs. The "Mount Elbert" site was selected to drill a stratigraphic test well to acquire a full suite of wireline log, core, and formation pressure test data. Drilling results and data interpretation confirmed pre-drill predictions and thus increased confidence in both the prospect interpretation methods and in the wider ANS gas hydrate resource estimates. The interpreted data from the Mount Elbert well provide insight into and reduce uncertainty of key gas hydrate-bearing reservoir properties, enable further refinement and validation of the numerical simulation of the production potential of both MPU and broader ANS gas hydrate resources, and help determine viability of potential field sites for future extended term production testing. Drilling and data acquisition operations demonstrated that gas hydrate

  10. The attitudes of the undergraduate nursing students towards lesbian women and gay men.

    Science.gov (United States)

    Unlu, Hayriye; Beduk, Tülin; Duyan, Veli

    2016-12-01

    This study was conducted to determine the attitudes of undergraduate nursing students towards lesbian women and gay men. Nursing education in Turkey is conducted holistically; in other words, it is an integration of the physical, spiritual, mental and social realms. Students are therefore expected to not express any discrimination due to factors such as religion, language, race and gender. However, some serious problems still exist in terms of the practical applications of that philosophy. This study was descriptive. This study included 964 students. The Attitudes towards Lesbian Women and Gay Men scale and a questionnaire were used to learn about the attitudes of undergraduate nursing students regarding gay men and lesbian women. Results of this study have indicated that the attitudes of religiously educated and/or conservative students towards lesbian women and gay men were negative. Female students from families with high incomes and highly educated families attended social activities and read more than other female students. The students with free life choice options expressed very positive attitudes towards gay men. The nursing education curriculum should cover information about patients with diverse sexual orientations and their absolute rights for equally optimal healthcare. Strategies to discourage traditional gender role stereotypes and educational and media experiences for better acceptance of sexual minorities need to be developed by educational policy makers. Antidiscrimination policies protecting lesbian women and gay men should be developed by the legislative authorities and then taught to students during their nursing education. Getting familiar with diverse sexual orientations might create awareness among nursing students and reduce their attitudinal and behavioural prejudices and biases. To provide equal healthcare services for all patients, nurses must have accurate information about lesbian women, gay men and modify their attitude and behaviour

  11. Literature for Today's Gay and Lesbian Teens: Subverting the Culture of Silence

    Science.gov (United States)

    Norton, Terry L.; Vare, Jonatha W.

    2004-01-01

    Several books that provide guidance for the gay and lesbian teenagers, their friends and families are presented. The books depict the challenges faced by the gay and lesbian teenagers, conflicts among the young adults and parents or caretakers and the rejections faced by the heterosexual parents and friends.

  12. Minority Stress, Masculinity, and Social Norms Predicting Gay Men's Health Risk Behaviors

    Science.gov (United States)

    Hamilton, Christopher J.; Mahalik, James R.

    2009-01-01

    The authors examined the contributions of the minority stress model, traditional masculine gender roles, and perceived social norms in accounting for gay men's use of alcohol, tobacco, illicit drugs, and risky sexual practices. Three hundred fifteen gay men recruited from listserv communities completed measures assessing internalized homophobia,…

  13. Impact of Compound Hydrate Dynamics on Phase Boundary Changes

    Science.gov (United States)

    Osegovic, J. P.; Max, M. D.

    2006-12-01

    Compound hydrate reactions are affected by the local concentration of hydrate forming materials (HFM). The relationship between HFM composition and the phase boundary is as significant as temperature and pressure. Selective uptake and sequestration of preferred hydrate formers (PF) has wide ranging implications for the state and potential use of natural hydrate formation, including impact on climate. Rising mineralizing fluids of hydrate formers (such as those that occur on Earth and are postulated to exist elsewhere in the solar system) will sequester PF before methane, resulting in a positive relationship between depth and BTU content as ethane and propane are removed before methane. In industrial settings the role of preferred formers can separate gases. When depressurizing gas hydrate to release the stored gas, the hydrate initial composition will set the decomposition phase boundary because the supporting solution takes on the composition of the hydrate phase. In other settings where hydrate is formed, transported, and then dissociated, similar effects can control the process. The behavior of compound hydrate systems can primarily fit into three categories: 1) In classically closed systems, all the material that can form hydrate is isolated, such as in a sealed laboratory vessel. In such systems, formation and decomposition are reversible processes with observed hysteresis related to mass or heat transfer limitations, or the order and magnitude in which individual hydrate forming gases are taken up from the mixture and subsequently released. 2) Kinetically closed systems are exposed to a solution mass flow across a hydrate mass. These systems can have multiple P-T phase boundaries based on the local conditions at each face of the hydrate mass. A portion of hydrate that is exposed to fresh mineralizing solution will contain more preferred hydrate formers than another portion that is exposed to a partially depleted solution. Examples of kinetically closed

  14. 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.

  15. Military Gay Ban Revisited: Is our Military Ready for Change?

    Science.gov (United States)

    2009-02-20

    support from the lesbian, gay, bi-sexual, transgender ( LGBT ) community and in return made several campaign promises along the way. One of the campaign ...Lesbian, Gay, Bi-sexual, Transgender] ( LGBT ) rights is exploited by those seeking to divide us. But at its core, this issue is about who we are as...No. 85. July 2007. Donnelly, Elaine. Who Will Confront the “ LGBT Left?”. Center for Military Readiness. (5 February 2008). Frank

  16. Social Media in Gay London: Tinder as an Alternative to Hook-Up Apps

    Directory of Open Access Journals (Sweden)

    Freddy MacKee

    2016-09-01

    Full Text Available The article explores how the mobile app Tinder complements dating practices and the wider app ecosystem gay men use in London. Within the local gay community discourse, Tinder is said to be a site where the gay “nice guys” go, rendering the platform as a socially constructed environment where gay men behave in a diametrically opposed way to the normative hyper-sexualized behavior of widespread gay hook-up apps. The research question, therefore, is whether Tinder is in fact a place where these “nice guys” go and where one would find them. Through an ethnographic methodology conducted both online and offline, a case is built on how initial conceptions about the app cannot be fully studied or interpreted without understanding the place it holds among other social networks. Evidence is presented to support the case that gay users of Tinder do, in fact, curate the portrayal of their digital identity to present a considerably less sexualized persona with the hopes of finding dates or a relationship. This, however, does not mean that users refrain from using other platforms in parallel as a way of exploring different subject positions and motivations. Behavior and normativity on Tinder are largely explained both by context and also by the design of the platform, which imports and displays personal data from other social networks. Findings should be limited to the population and location proposed as the fieldsite.

  17. Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample.

    Science.gov (United States)

    Muraoka, Michihiro; Susuki, Naoko; Yamaguchi, Hiroko; Tsuji, Tomoya; Yamamoto, Yoshitaka

    2016-03-21

    Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future energy resources and energy storage media. To develop a method for gas production from natural MH-bearing sediments and hydrate-based technologies, it is imperative to understand the thermal properties of gas hydrates. The thermal properties' measurements of samples comprising sand, water, methane, and MH are difficult because the melting heat of MH may affect the measurements. To solve this problem, we performed thermal properties' measurements at supercooled conditions during MH formation. The measurement protocol, calculation method of the saturation change, and tips for thermal constants' analysis of the sample using transient plane source techniques are described here. The effect of the formation heat of MH on measurement is very small because the gas hydrate formation rate is very slow. This measurement method can be applied to the thermal properties of the gas hydrate-water-guest gas system, which contains hydrogen, CO2, and ozone hydrates, because the characteristic low formation rate of gas hydrate is not unique to MH. The key point of this method is the low rate of phase transition of the target material. Hence, this method may be applied to other materials having low phase-transition rates.

  18. Rheological properties of hydrate suspensions in asphaltenic crude oils; Proprietes rheologiques de suspensions d'hydrate dans des bruts asphalteniques

    Energy Technology Data Exchange (ETDEWEB)

    Marques de Toledo Camargo, R.

    2001-03-01

    The development of offshore oil exploitation under increasing water depths has forced oil companies to increase their understanding of gas hydrate formation and transportation in multiphase flow lines in which a liquid hydrocarbon phase is present. This work deals with the flow behaviour of hydrate suspensions in which a liquid hydrocarbon is the continuous phase. Three different liquid hydrocarbons are used: an asphaltenic crude oil, a condensate completely free of asphaltenes and a mixture between the asphaltenic oil and heptane. The rheological characterisation of hydrate suspensions is the main tool employed. Two original experimental devices are used: a PVT cell adapted to operate as a Couette type rheometer and a semi-industrial flow loop. Hydrate suspensions using the asphaltenic oil showed shear-thinning behaviour and thixotropy. This behaviour is typically found in flocculated systems, in which the particles attract each other forming flocs of aggregated particles at low shear rates. The suspensions using the condensate showed Newtonian behaviour. Their relative viscosities were high, which suggests that an aggregation process between hydrate particles takes. place during hydrate formation. Finally, hydrate suspensions using the mixture asphaltenic oil-heptane showed shear-thinning behaviour, thixotropy and high relative viscosity. From these results it can be inferred that, after the achievement of the hydrate formation process, the attractive forces between hydrate particles are weak. making unlikely pipeline obstruction by an aggregation process. Nevertheless, during the hydrate formation, these attractive forces can be sufficiently high. It seems that the hydrate surface wettability is an important parameter in this phenomena. (author)

  19. Places for all? Cape Town’s public library services to gays and lesbians

    Directory of Open Access Journals (Sweden)

    Genevieve Hart

    2010-01-01

    Full Text Available The article reports on an investigation of the provision of gay and lesbian literature and of information services to gays and lesbians in Cape Town’s public libraries. Although by definition public libraries serve all members of a community, the international literature suggests that they neglect the reading and information needs and interests of gays and lesbians. The progressive South African Constitution views the rights of gays and lesbians as human rights; yet homophobia is prevalent. Using a questionnaire, the study explored attitudes and practices of 69 senior librarians, responsible for collection development, across all six of Cape Town’s library districts. The situation was found to be “spotty” with only 26 respondents believing that their library service is meeting the needs of gays and lesbians. The survey found contradictions between stated beliefs and behaviours. Thus, although most agree that LGBT rights to information and equal services are human rights, only 55% consider LGBT people in their selection procedures and very little material is acquired. Information services are thin with, for example, only 10% of the libraries in the survey providing LGBT related information in their community information files.

  20. Predicting Portuguese Psychology Students' Attitudes Toward the Psychological Development of Children Adopted by Lesbians and Gay Men.

    Science.gov (United States)

    Gato, Jorge; Fontaine, Anne Marie

    2016-11-01

    The present study seeks to ascertain the attitudes of Portuguese psychology students (future psychologists) toward the development of children adopted by lesbian and gay parents. Each participant (N = 182) read a vignette describing an adoption of a child by lesbian and gay persons. After reading the vignette, participants rated four different aspects of the future development of the adopted child (psychosocial adjustment, victimization, psychological disturbance, and normative sexuality). Furthermore, participants were asked about their gender, interpersonal contact with lesbians and gay men, gender role attitudes, and attitudes toward lesbians and gay men. Future psychologists' attitudes toward the developmental outcomes of children adopted by lesbians and gay men were associated with negative attitudes toward non-heterosexuals, which in turn correlated to interpersonal contact with lesbians and gay men and adherence to gender conservative values. These results clearly highlight the central role of social attitudes and the need for cultural competence training of future psychologists that encourages interpersonal contact with non-heterosexuals and discourages traditional gender roles and negative attitudes toward lesbian and gay men.