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1

LNG vapor dispersion prediction with the DEGADIS dense-gas dispersion model. Topical report, April 1988July 1990. Documentation  

Microsoft Academic Search

The topical report is one of a series on the development of methods for LNG vapor dispersion prediction for regulatory application. The results indicate that the DEGADIS model is superior both phenomenologically and in performance to the Gaussian line source model promulgated in 49 CFR 193 for LNG vapor dispersion simulation. Availability of the DEGADIS model for VAX and IBM-PC

J. Havens; T. Spicer

1990-01-01

2

Dispersion phenomenology of LNG vapor in the Burro and Coyote LNG spill experiments  

SciTech Connect

Various physical phenomena affecting LNG vapor dispersion were observed in LNG spill experiments conducted by the Lawrence Livermore National Laboratory. Unterstanding the phenomena is necessary in predicting the size of the hazardous region of vapor concentration following a spill. Gravity flow of the cold dense vapor increased cloud width while density stratification and heat flow from the ground had substantial effects on the mixing rate with air. Density stratification inhibits turbulent mixing while heat flow into the cloud promotes it through a number of processes including buoyancy. Some possible instances of buoyancy were observed in the experiments, and calculations indicate that modest amount of additional heat might substantially increase cloud dispersion. In the experiments, these phenomena led to a dependence of the maximum distance L-script to the lower flammability limit on source rate, wind speed, and atmospheric stability that was substantially different from the prediction of the Gaussian plume model. Including these phenomena in predictive models is important for their model. Time-dependent features of the concentration field due to turbulence and rapid phase-transition explosions, which also affect L-script, were examined by applying a space--time interpolation scheme to the concentration data.

Morgan D.L. Jr.

1987-11-01

3

Regulatory Application of Wind Tunnel Models and Complex Mathematical Models for Simulating Atmospheric Dispersion of LNG Vapor. Topical Report, September 1988-August 1994.  

National Technical Information Service (NTIS)

A reassessment of wind-tunnel methods for modeling liquefied natural gas (LNG) vapor dispersion at very low wind speeds is suggested. An evaluation of wind tunnel simulations of LNG vapor dispersion indicates that the assumptions required for scaling wind...

J. Havens T. Spicer H. Walker

1994-01-01

4

LNG fire and vapor control system technologies  

SciTech Connect

This report provides a review of fire and vapor control practices used in the liquefied natural gas (LNG) industry. Specific objectives of this effort were to summarize the state-of-the-art of LNG fire and vapor control; define representative LNG facilities and their associated fire and vapor control systems; and develop an approach for a quantitative effectiveness evaluation of LNG fire and vapor control systems. In this report a brief summary of LNG physical properties is given. This is followed by a discussion of basic fire and vapor control design philosophy and detailed reviews of fire and vapor control practices. The operating characteristics and typical applications and application limitations of leak detectors, fire detectors, dikes, coatings, closed circuit television, communication systems, dry chemicals, water, high expansion foam, carbon dioxide and halogenated hydrocarbons are described. Summary descriptions of a representative LNG peakshaving facility and import terminal are included in this report together with typical fire and vapor control systems and their locations in these types of facilities. This state-of-the-art review identifies large differences in the application of fire and vapor control systems throughout the LNG industry.

Konzek, G.J.; Yasutake, K.M.; Franklin, A.L.

1982-06-01

5

Monitoring of LNG Vapors - Phase I.  

National Technical Information Service (NTIS)

This report documents the development and subsequent field testing of two rapid response instruments for the detection of methane gas in the vapor resulting from an LNG spill. The instruments were: a laser instrument with a 0.005 second response time and ...

E. D. Hinckley

1979-01-01

6

FEM3A simulations of selected LNG vapor barrier verification field tests  

SciTech Connect

In order to evaluate and eventually predict the possible mitigating effects of vapor fences on the dispersion of the vapor cloud resulting from an accidental liquefied natural gas (LNG) spill in storage areas, a research program was initiated to evaluate methods for predicting LNG dispersion distances for realistic facility configurations. As part of the program, Lawrence Livermore National Laboratory (LLNL) conducted a series of large-scale field experiments called the LNG Vapor Barrier Verification Field Trials (also referred to as the Falcon Series) at the Liquefied Gaseous Fuels Spill Test Facility (LGFSTF), Nevada. Objectives were (1) to provide a data base on LNG vapor dispersion from spill involving complex field obstacles to assist in validation of wind tunnel and mathematical models, and (2) to assess the effectiveness of vapor fences for mitigating LNG vapor dispersion hazards in the events of an accidental spill. Five spill experiments were conducted on water in order to generate vapor at rates equivalent to the liquid spill rates. In this study, the FEM3A model was applied to simulate four of the Falcon experiments. The objectives of this study were, through numerical modeling and a detailed model-data comparison: (1) to improve our understanding of LNG vapor dispersion involving vapor barriers, (2) to assess FEM3A in modeling such complex vapor dispersion scenarios, and (3) to complement the results of field and wind tunnel tests, such as providing plausible explanations for unexpected results and filling in data gaps due to instrument failure or limited array size. Toward these goals, the relevant field measurements were analyzed and several series of 2-D and 3-D simulations were carried out. 11 refs., 93 figs., 11 tabs.

Chan, S.T.

1990-10-01

7

Coyote series data report LLNL/NWC 1981 LNG spill tests dispersion, vapor burn, and rapid-phase-transition. Volume 1. [7 experiments with liquefied natural gas, 2 with liquid methane, and one with liquid nitrogen  

SciTech Connect

The Coyote series of liquefied natural gas (LNG) spill experiments was performed at the Naval Weapons Center (NWC), China Lake, California, during the summer and fall of 1981. These tests were a joint effort of the Lawrence Livermore National Laboratory (LLNL) and the NWC and were sponsored by the US Department of Energy (DOE) and the Gas Research Institute. There were ten Coyote experiments, five primarily for the study of vapor dispersion and burning vapor clouds, and five for investigating the occurrence of rapid-phase-transition (RPT) explosions. Each of the last four of the five RPT tests consisted of a series of three spills. Seven experiments were with LNG, two were with liquid methane (LCH/sub 4/), and one was with liquid nitrogen (LN/sub 2/). Three arrays of instrumentation were deployed. An array of RPT diagnostic instruments was concentrated at the spill pond and was operated during all of the tests, vapor burn as well as RPT. The wind-field array was operated during the last nine experiments to define the wind direction and speed in the area upwind and downwind of the spill pond. The gas-dispersion array was deployed mostly downwind of the spill pond to measure gas concentration, humidity, temperature, ground heat flux, infrared (IR) radiation, and flame-front passage during three of the vapor dispersion and burn experiments (Coyotes 3, 5, and 6). High-speed color motion pictures were taken during every test, and IR imagery (side and overhead) was obtained during some vapor-burn experiments. Data was obtained by radiometers during Coyotes 3, 6, and 7. This report presents a comprehensive selection of the data obtained. It does not include any data analysis except that required to determine the test conditions and the reliability of the data. Data analysis is to be reported in other publications. 19 references, 76 figures, 13 tables.

Goldwire, H.C. Jr.; Rodean, H.C.; Cederwall, R.T.; Kansa, E.J.; Koopman, R.P.; McClure, J.W.; McRae, T.G.; Morris, L.K.; Kamppinen, L.; Kiefer, R.D.

1983-10-01

8

Performance metrics for evaluating liquefied natural gas, vapor dispersion models  

Microsoft Academic Search

New performance metrics are necessary to quantify the inherent margins of safety11In this paper, margin of safety is an occupational safety phrase, and it is expressed as a ratio. in vapor dispersion models for liquefied natural gas (LNG) spills. Currently, vapor dispersion model calculations in the 49 Code of Federal Regulations, Part 193 as well as Standard 59A of the

Frank A. Licari

2010-01-01

9

Summary of LNG Safety Research: Supplement - Task III.  

National Technical Information Service (NTIS)

Results from major published research programs related to assessment and alleviation of potential LNG hazards are described. Topics covered include: vaporization and dispersion from LNG spills, boiling heat transfer rates for LNG on water, superheat 'expl...

E. Drake R. Reid S. Atallah

1974-01-01

10

Vapor burn analysis for the Coyote series LNG spill experiments  

SciTech Connect

A major purpose of the Coyote series of field experiments at China Lake, California, in 1981 was to study the burning of vapor clouds from spills of liquefied natural gas (LNG) on water. Extensive arrays of instrumentation were deployed to obtain micrometeorological, gas concentration, and fire-related data. The instrumentation included in situ sensors of various types, high-speed motion picture cameras, and infrared (IR) imagers. Five of the total of ten Coyote spill experiments investigated vapor burns. The first vapor-burn experiment, Coyote 2, was done with a small spill of LNG to assess instrument capability and survivability in vapor cloud fires. The emphasis in this report is on the other four vapor-burn experiments: Coyotes 3, 5, 6, and 7. The data are analyzed to determine fire spread, flame propagation, and heat flux - quantities that are related to the determination of the damage zone for vapor burns. The results of the analyses are given here. 20 references, 57 figures, 7 tables.

Rodean, H.C.; Hogan, W.J.; Urtiew, P.A.; Goldwire, H.C. Jr.; McRae, T.G.; Morgan, D.L. Jr.

1984-04-01

11

High Expansion Foam for LNG Vapor Mitigation. Topical Report September 1987-December 1989.  

National Technical Information Service (NTIS)

One of the purposes of these high expansion foam systems is to reduce the extent of the hazardous vapor cloud generated during an accidental LNG release. Should the LNG ignite, these systems serve the additional function of controlling the LNG fire and mi...

S. Atallah J. N. Shah M. E. Peterlinz

1990-01-01

12

Ignition sources of LNG vapor clouds. Final report aug 80-nov 81  

Microsoft Academic Search

This report presents a series of coordinated efforts to develop a data base for ignition sources of LNG vapor clouds in urban areas. A literature survey and field surveys of an urban area and of an LNG plant were conducted. Over 150 potential ignition sources were identified. The main source characteristics affecting ignition were analyzed, covering source density, accessibility to

D. J. Jeffreys; N. A. Moussa; R. N. Caron; D. S. Allan

1982-01-01

13

Dike insulation for LNG (liquefied natural gas) vapor mitigation. Topical report, September 1987-December 1988  

SciTech Connect

Insulating materials may be applied to the surfaces of LNG impoundment areas in order to reduce the rate of heat transfer from the ground to any accidentally released LNG. This would result in a reduction of the extent of the flammable vapor cloud. Numerous studies have been carried out to develop dike insulating materials and to evaluate and compare their thermal and physical properties. This report summarizes the results of these studies. The authors conclude that an insulating polymer concrete (IPC) exhibits the most desirable thermal and mechanical characteristics. Design guidelines for the proper installation of IPC on LNG-impoundment surfaces and procedures for estimating total initial and annual maintenance costs are provided.

Atallah, S.; Peterlinz, M.E.; Shah, J.N.

1989-05-01

14

LNG SAFETY RESEARCH: FEM3A MODEL DEVELOPMENT  

Microsoft Academic Search

The objective of this report is to develop the FEM3A model for application to general scenarios involving dispersion problems with obstacles and terrain features of realistic complexity, and for very low wind speed, stable weather conditions as required for LNG vapor dispersion application specified in 49 CFR 193. The dispersion model DEGADIS specified in 49 CFR 193 is limited to

Jerry Havens; Iraj A. Salehi

2005-01-01

15

Vapor–liquid equilibria of LNG and gas condensate mixtures by the Nasrifar–Moshfeghian equation of state  

Microsoft Academic Search

The Nasrifar–Moshfeghian (NM) equation of state (EOS) is used to predict vapor–liquid equilibria (VLE) of multi-component mixtures. The systems under study consist of liquefied natural gases (LNG), gas condensates, an asymmetric system, slightly polar systems and gas\\/water systems. van der Waals mixing rules are used and no pure component parameter is adjusted; however, the predictions compare well with experimental data,

Kh Nasrifar; M Moshfeghian

2002-01-01

16

Falcon series data report: 1987 LNG vapor barrier verification field trials  

SciTech Connect

A series of five Liquefied Natural Gas Spills up to 66 m{sup 3} in volume were performed on water within a vapor barrier structure at Frenchman Flat on the Nevada Test Site as a part of a joint government/industry study. This data report presents a description of the tests, the test apparatus, the instrumentation, the meteorological conditions, and the data from the tests. 16 refs., 27 figs., 8 tabs.

Brown, T.C.; Cederwall, R.T.; Chan, S.T.; Ermak, D.L.; Koopman, R.P.; Lamson, K.C.; McClure, J.W.; Morris, L.K.

1990-06-01

17

Controlling the Hazards from LNG Spills on the Ground, LNG Firefighting Methods and Their Effects Application to Gas de France Terminals.  

National Technical Information Service (NTIS)

Gaz de France has developed a mathematical model to calculate vapor dispersion from accidental LNG spills on land. This model has been applied to make clear the influence of certain parameters in reducing the extension of the plumes. Based on the results ...

F. Bellus H. Cochard J. Mauger R. Vincent

1978-01-01

18

49 CFR 193.2059 - Flammable vapor-gas dispersion protection.  

Code of Federal Regulations, 2010 CFR

...order to account for additional cloud dilution which may be caused...parameters must be used in computing dispersion distances: ...upwind and downwind of the vapor cloud has dense vegetation and that the vapor cloud height is more than ten...

2010-10-01

19

49 CFR 193.2059 - Flammable vapor-gas dispersion protection.  

Code of Federal Regulations, 2010 CFR

...order to account for additional cloud dilution which may be caused...parameters must be used in computing dispersion distances: ...upwind and downwind of the vapor cloud has dense vegetation and that the vapor cloud height is more than ten...

2009-10-01

20

LNG SAFETY RESEARCH: FEM3A MODEL DEVELOPMENT  

SciTech Connect

The objective of this report is to develop the FEM3A model for application to general scenarios involving dispersion problems with obstacles and terrain features of realistic complexity, and for very low wind speed, stable weather conditions as required for LNG vapor dispersion application specified in 49 CFR 193. The dispersion model DEGADIS specified in 49 CFR 193 is limited to application for dispersion over smooth, level terrain free of obstacles (such as buildings, tanks, or dikes). There is a need for a dispersion model that allows consideration of the effects of terrain features and obstacles on the dispersion of LNG vapor clouds. Project milestones are: (1) Simulation of Low-Wind-Speed Stable Atmospheric Milestones Conditions; (2) Verification for Dispersion over Rough Surfaces, With And Without Obstacles; and (3) Adapting the FEM3A Model for General Application. Results for this quarter are work continues to underway to address numerical problems during simulation of low-wind-speed, stable, atmospheric conditions with FEM3A. Steps 1 and 2 in the plan outlined in the first Quarterly report are complete and steps 3 and 4 are in progress. During this quarter, we have been investigating the effect upon numerical stability of the heat transfer model used to predict the surface-to-cloud heat transfer, which can be important for LNG vapor dispersion. Previously, no consideration has been given to ground cooling as a result of heat transfer to the colder gas cloud in FEM3A. The present effort is directed to describing the ground surface temperature decrease as a function of time.

Jerry Havens; Iraj A. Salehi

2005-05-10

21

LNG SAFETY RESEARCH: FEM3A MODEL DEVELOPMENT  

SciTech Connect

This quarterly report for DE-FG26-04NT42030 covers a period from October 1, 2004 to December 31, 2004. On December 9, 2004 a meeting was held in Morgantown to rescope the LNG safety modeling project such that the work would complement the DOE's efforts relative to the development of the intended LNG-Fluent model. It was noted and discussed at the December 9th meeting that the fundamental research being performed on surface to cloud heat transfer and low wind speed issues will be relevant to the development of the DOE LNG/Fluent Model. In general, it was decided that all research to be performed from December 9th through the remainder of the contract is to be focused on the development of the DOE LNG/Fluent model. In addition, all GTI activities for dissemination and transfer of FEM3A will cease and dissemination activities will focus on the new DOE LNG/Fluent model. The proposed new scope of work is presented in section 4 of this report. The work reported in the present document relates to the original scope of work which was in effect during the reporting period. The future work will be re-scoped to meet the requirements of the new scope of work. During the report period work was underway to address numerical problems present during simulation of low-wind-speed, stable, atmospheric conditions with FEM3A. Steps 1 and 2 in the plan outlined in the first Quarterly report are complete and steps 3 and 4 are in progress. During this quarter, the University of Arkansas has been investigating the effect upon numerical stability of the heat transfer model used to predict the surface-to-cloud heat transfer, which can be important for LNG vapor dispersion. Previously, no consideration has been given to ground cooling as a result of heat transfer to the colder gas cloud in FEM3A.

Jerry Havens; Iraj A. Salehi

2005-02-21

22

Electrodeless-discharge-vapor-lamp-based Faraday anomalous-dispersion optical filter.  

PubMed

We report an excited-state Faraday anomalous-dispersion optical filter operating on the rubidium 5P(3/2)-5D(5/2) transition (775.9 nm in vacuum) without the use of a pump laser. An electrodeless discharge vapor lamp is employed to replace the Rb vapor cell in a traditional Faraday anomalous-dispersion optical filter system. Atoms can be excited by power rather than a complex frequency-locked pump laser. A proof-of-concept experimental demonstration with a maximum transmission of 1.9% and a filter bandwidth of 650 MHz is presented. PMID:22139259

Sun, Qinqing; Zhuang, Wei; Liu, Zhiwen; Chen, Jingbiao

2011-12-01

23

Determination of gas dispersion in vapor extraction of heavy oil and bitumen  

Microsoft Academic Search

In this work, a mathematical model is developed and simulated to determine gas dispersion along with solubility during the vapor extraction (Vapex) of live oil from a laboratory scale physical model. The physical model is a rectangular block of homogenous porous medium saturated with heavy oil and bitumen. At a given temperature and pressure, the block is initially exposed on

Ronak A. Kapadia; Simant R. Upreti; Ali Lohi; Ioannis Chatzis

2006-01-01

24

The Effective Diffusion\\/Dispersion Coefficient in Vapor Extraction of Heavy Oil  

Microsoft Academic Search

In this study, a new correlation for determination of effective diffusion\\/dispersion coefficients in the vapor extraction of heavy oil\\/bitumen (VAPEX) is introduced. This model takes into account the solvent concentration as well as the drainage height and permeability dependency of these coefficients. The concentration dependency in this model stems from the mixture viscosity changes, while the height dependency appears directly

A. Yazdani; B. Maini

2009-01-01

25

Water vapor absorption into amorphous hydrophobic drug/poly(vinylpyrrolidone) dispersions.  

PubMed

Water vapor absorption isotherms were measured for three amorphous hydrophobic drug/poly(vinylpyrrolidone) (PVP) dispersions in the concentration range 10-90% w/w PVP. Experimental isotherms were compared to predicted isotherms calculated using each individual component isotherm multiplied by its weight fraction. Indomethacin (IMC)/PVP, ursodeoxycholic acid (UDCA)/PVP and indapamide (IDP)/PVP amorphous dispersions all exhibited experimental isotherms reduced relative to predicted isotherms indicating that dispersion formation altered the water vapor absorption properties of the individual components. For all three drug/PVP systems, deviation from predicted water uptake was greatest close to the 1:1 drug:PVP monomer composition, indicating that intermolecular interaction in amorphous dispersions affects the water uptake properties of the individual components. Using dry glass transition temperature (T(g)) data, the extent of drug/PVP interaction was shown to be greatest in the IDP/PVP system, which could explain why the largest reduction in water vapor absorption was found in this system. The plasticizing effect of absorbed water varied according to dry dispersion PVP content in all systems and the resulting nonideal changes in free volume, calculated using the Vrentas model, were greatest close to the 1:1 drug:PVP monomer composition. A three-component Flory-Huggins model successfully predicted isotherms for IMC/PVP compositions from 60 to 90% w/w PVP and identified an IMC-PVP interaction parameter chi in the range 1.27-1.49, values that suggest poor homogeneity of mixing in the dry system. These data indicate that amorphous dispersion formation causes both chemical and physical changes in the individual amorphous components that can have a significant effect on their water vapor absorption properties. PMID:12226842

Crowley, Kieran J; Zografi, George

2002-10-01

26

Determination of the dispersion constant in a constrained vapor bubble thermosyphon  

NASA Astrophysics Data System (ADS)

The isothermal profiles of the extended meniscus in a quartz cuvette were measured in a gravitational field using an image analyzing interferometer which is based on computer enhanced video microscopy of the naturally occurring interference fringes. The experimental results for heptane and pentane menisci were analyzed using the extended Young Laplace Equation. These isothermal results characterized the interfacial force field in-siru at the start of the heat transfer experiments by quantifying the dispersion constant, which is a function of the liquid-solid system and cleaning procedures. The experimentally obtained values of the disjoining pressure and the dispersion constants were compared to that predicted from the DLP theory and good agreements were obtained. The measurements are critical to the subsequent non-isothermal experiments because one of the major variables in the heat sink capability of the Constrained Vapor Bubble Thermosyphon, CVBT, is the dispersion constant. In all previous studies of micro heat pipes the value of the dispersion constant has been 'estimated'. One of the major advantages of the current glass cell is the ability to view the extended meniscus at all times. Experimentally, we find that the extended Young-Laplace Equation is an excellent model for the force field at the solid-liquid-vapor interfaces.

Dasgupta, Sunando; Plawsky, Joel L.; Wayner, Peter C., Jr.

1995-01-01

27

46 CFR 154.1854 - Methane (LNG) as fuel.  

Code of Federal Regulations, 2012 CFR

...methane (LNG) vapors are used as fuel in the main propulsion system...master shall ensure that the fuel oil fired pilot under § 154...the vessel is on the navigable waters of the United States. (b) When the methane (LNG) fuel supply is shut down due...

2011-10-01

28

46 CFR 154.1854 - Methane (LNG) as fuel.  

Code of Federal Regulations, 2012 CFR

...methane (LNG) vapors are used as fuel in the main propulsion system...master shall ensure that the fuel oil fired pilot under § 154...the vessel is on the navigable waters of the United States. (b) When the methane (LNG) fuel supply is shut down due...

2012-10-01

29

Determination of the dispersion constant in a constrained vapor bubble thermosyphon  

NASA Astrophysics Data System (ADS)

The isothermal profiles of the extended meniscus in a quartz cuvette were measured in a gravitational field using an image analyzing interferometer which is based on computer enhanced video microscopy of the naturally occurring interference fringes. The experimental results for heptane and pentane menisci were analyzed using the extended Young-Laplace equation. These isothermal results characterized the interfacial force field in-situ at the start of the heat transfer experiments by quantifying the dispersion constant, which is a function of the liquid-solid system and cleaning procedures. The experimentally obtained values of the disjoining pressure and the dispersion constants were compared to that predicted from the DLP theory and good agreements were obtained. The measurements are critical to the subsequent non-isothermal experiments because one of the major variables in the heat sink capability of the CVBT is the dispersion constant. In all previous studies of micro heat pipes the value of the dispersion constant has been 'guesstimated'. One of the major advantages of the current glass cell is the ability to view the extended meniscus at all times. Experimentally. we find that the extended Young-Laplace equation is an excellent model for the force field at the solid-liquid-vapor interfaces.

Dasgupta, Sunando.; Plawsky, Joel L.; Wayner, Peter C., Jr.

1993-12-01

30

77 FR 58373 - Trunkline LNG Company, LLC; Trunkline LNG Export, LLC; Trunkline Gas Company, LLC; Notice of...  

Federal Register 2010, 2011, 2012, 2013

...feed gas line to supply natural gas to the liquefaction facility from existing gas transmission pipelines; Approximately...Construction of the planned feed gas pipeline, LNG line, and vapor...general headings: Geology and soils; Land use; Water...

2012-09-20

31

Hazards of LNG spillage in marine transportation. Final report, December 1968June 1969  

Microsoft Academic Search

An investigation of the hazard of spillage of liquefied natural gas onto water is described. About 2000 gallons of LNG were consumed in various tests. The initial vaporization rate of LNG following spillage was found to be 0.037 lbs\\/sq ft sec; when the spill was confined, this vaporization rate was moderated after about 20 seconds by the growth of an

D. S. Burgess; J. N. Murphy; M. G. Zabetakis

1970-01-01

32

Caribbean LNG project marks progress; LNG tanker launched  

SciTech Connect

World LNG trade continues to expand as construction of a major LNG project in the Caribbean hits full stride this fall and another LNG carrier was launched earlier this year. Engineering is nearly complete and construction is nearing midway on Trinidad`s Atlantic LNG. In Japan, NKK Corp. launched another LNG tanker that employs the membrane-storage system. The 50-mile pipeline to move natural gas to the Atlantic LNG facility is also on track for completion by October 1998.

NONE

1997-10-20

33

Comparative safety analysis of LNG storage tanks  

SciTech Connect

LNG storage tank design and response to selected release scenarios were reviewed. The selection of the scenarios was based on an investigation of potential hazards as cited in the literature. A review of the structure of specific LNG storage facilities is given. Scenarios initially addressed included those that most likely emerge from the tank facility itself: conditions of overfill and overflow as related to liquid LNG content levels; over/underpressurization at respective tank vapor pressure boundaries; subsidence of bearing soil below tank foundations; and crack propagation in tank walls due to possible exposure of structural material to cryogenic temperatures. Additional scenarios addressed include those that result from external events: tornado induced winds and pressure drops; exterior tank missile impact with tornado winds and rotating machinery being the investigated mode of generation; thermal response due to adjacent fire conditions; and tank response due to intense seismic activity. Applicability of each scenario depended heavily on the specific tank configurations and material types selected. (PSB)

Fecht, B.A.; Gates, T.E.; Nelson, K.O.; Marr, G.D.

1982-07-01

34

LNG risk management  

Microsoft Academic Search

A general methodology is presented for conducting an analysis of the various aspects of the hazards associated with the storage and transportation of liquefied natural gas (LNG) which should be considered during the planning stages of a typical LNG ship terminal. The procedure includes the performance of a hazards and system analysis of the proposed site, a probability analysis of

Paul Martino

1980-01-01

35

Rapid removal of selected volatile organic compounds from gaseous mixtures using a new dispersive vapor extraction technique: a feasibility study.  

PubMed

A new dispersive vapor extraction (DVE) technique for rapid removal of selected volatile organic compounds (VOCs) from gaseous mixtures was investigated. In this technique, less than 1.0 mL of a volatile solvent was vaporized for 8 min in a 250-mL flask containing a gaseous mixture. The flask was then cooled under running tap water for 2-3 min to induce condensation of the vapor and co-extraction of the VOCs from the headspace. The technique was tested over a concentration range of 4-23 ppb, and resulted in extraction efficiencies ranging from 80 to 97% for the VOCs tested. Because of its simplicity and the relatively short sampling time, DVE could potentially lead to high sample throughput and rapid air analysis. PMID:20602963

Farrell, E S; Pacey, G E

2010-05-26

36

Characterization of laser seeding by use of group-velocity dispersion in an atomic-vapor filter  

Microsoft Academic Search

A method for measuring laser seeding efficiencies by use of group-velocity dispersion has been developed. By tuning the laser near a resonance in an atomic-vapor filter it is possible to temporally decouple the seeded (narrow-band) light from the unseeded (broadband) light. We measured a seeding efficiency of 99.8% of the third harmonic of an injection-seeded Ti:sapphire laser. A model for

Azer P. Yalin; Peter F. Barker; Richard B. Miles

2000-01-01

37

High efficiency Brayton cycles using LNG  

DOEpatents

A modified, closed-loop Brayton cycle power conversion system that uses liquefied natural gas as the cold heat sink media. When combined with a helium gas cooled nuclear reactor, achievable efficiency can approach 68 76% (as compared to 35% for conventional steam cycle power cooled by air or water). A superheater heat exchanger can be used to exchange heat from a side-stream of hot helium gas split-off from the primary helium coolant loop to post-heat vaporized natural gas exiting from low and high-pressure coolers. The superheater raises the exit temperature of the natural gas to close to room temperature, which makes the gas more attractive to sell on the open market. An additional benefit is significantly reduced costs of a LNG revaporization plant, since the nuclear reactor provides the heat for vaporization instead of burning a portion of the LNG to provide the heat.

Morrow, Charles W. (Albuquerque, NM)

2006-04-18

38

Insulating LNG (liquified natural gas) storage tank containment dikes with a lightweight polymer concrete  

Microsoft Academic Search

The natural gas industry has always been concerned ith accidental spills of liquified natural gas (LNG) from storage tanks into surrounding containment dikes. The LNG that is leaked to the dike area boils off and the vapors mix with the atmosphere forming a hazardous explsoive mixture within the dike walls. These hazardous mixtures can travel long distances into industrial or

Fontana

1987-01-01

39

Insulating LNG (Liquified Natural Gas) Storage Tank Containment Dikes with a Lightweight Polymer Concrete.  

National Technical Information Service (NTIS)

The natural gas industry has always been concerned with accidental spills of liquified natural gas (LNG) from storage tanks into surrounding containment dikes. The LNG that is leaked to the dike area boils off and the vapors mix with the atmosphere formin...

J. J. Fontana

1987-01-01

40

Analysis of Rollover phenomena and testing research of boil-off on the surface of LNG.  

National Technical Information Service (NTIS)

When a large amount of LNG of different density and temperature is added to a partially filled LNG tank, temporarily stratified layers are present together. As time elapses the subsequent abrupt mixing of the layers leads to a great deal of vaporization o...

H. Kim S. Y. Kim Y. S. Sohn

1994-01-01

41

A review of large-scale LNG spills: experiments and modeling.  

PubMed

The prediction of the possible hazards associated with the storage and transportation of liquefied natural gas (LNG) by ship has motivated a substantial number of experimental and analytical studies. This paper reviews the experimental and analytical work performed to date on large-scale spills of LNG. Specifically, experiments on the dispersion of LNG, as well as experiments of LNG fires from spills on water and land are reviewed. Explosion, pool boiling, and rapid phase transition (RPT) explosion studies are described and discussed, as well as models used to predict dispersion and thermal hazard distances. Although there have been significant advances in understanding the behavior of LNG spills, technical knowledge gaps to improve hazard prediction are identified. Some of these gaps can be addressed with current modeling and testing capabilities. A discussion of the state of knowledge and recommendations to further improve the understanding of the behavior of LNG spills on water is provided. PMID:16271829

Luketa-Hanlin, Anay

2005-11-04

42

Vapor spill pipe monitor  

DOEpatents

The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

Bianchini, G.M.; McRae, T.G.

1983-06-23

43

Distribution of hydrocarbons among oil, water and vapor phases during oil dispersant toxicity tests  

Microsoft Academic Search

A major consideration in determining the desirability of using dispersants as an oil spill countermeasure is the extent to which the dispersant alters the exposure of water column organisms to the oil. The role of the dispersing chemical is to reduce the oil-water interfacial tension and thus increase the tendency for oil droplets to shear from the slick and become

A. Bobra; D. Mackay; W. Y. Shiu

1979-01-01

44

Insulating LNG (liquified natural gas) storage tank containment dikes with a lightweight polymer concrete  

SciTech Connect

The natural gas industry has always been concerned ith accidental spills of liquified natural gas (LNG) from storage tanks into surrounding containment dikes. The LNG that is leaked to the dike area boils off and the vapors mix with the atmosphere forming a hazardous explsoive mixture within the dike walls. These hazardous mixtures can travel long distances into industrial or residential areas surroungind LNG storage facilities. Studies by the natural gas industry indicate that the hazards associated with accidental spills of LNG from storage tanks can be makedly reduced by insulating the diked areas surrounding these tanks. In this manner, the heat transfer from the dike surface to the LNG is reduced. The insulating composite is used to construct a thermal barrier between the walls and floor of the dike an the spilled LNG. The thermal conductivity, porosity, and compression strength of a concrete, polymer composite insulating material is discussed. 6 refs., 8 figs., 5 tbs.

Fontana, J.J.

1987-08-01

45

An LNG release, transport, and fate model system for marine spills.  

PubMed

LNGMAP, a fully integrated, geographic information based modular system, has been developed to predict the fate and transport of marine spills of LNG. The model is organized as a discrete set of linked algorithms that represent the processes (time dependent release rate, spreading, transport on the water surface, evaporation from the water surface, transport and dispersion in the atmosphere, and, if ignited, burning and associated radiated heat fields) affecting LNG once it is released into the environment. A particle-based approach is employed in which discrete masses of LNG released from the source are modeled as individual masses of LNG or spillets. The model is designed to predict the gas mass balance as a function of time and to display the spatial and temporal evolution of the gas (and radiated energy field). LNGMAP has been validated by comparisons to predictions of models developed by ABS Consulting and Sandia for time dependent point releases from a draining tank, with and without burning. Simulations were in excellent agreement with those performed by ABS Consulting and consistent with Sandia's steady state results. To illustrate the model predictive capability for realistic emergency scenarios, simulations were performed for a tanker entering Block Island Sound. Three hypothetical cases were studied: the first assumes the vessel continues on course after the spill starts, the second that the vessel stops as soon as practical after the release begins (3 min), and the third that the vessel grounds at the closest site practical. The model shows that the areas of the surface pool and the incident thermal radiation field (with burning) are minimized and dispersed vapor cloud area (without burning) maximized if the vessel continues on course. For this case the surface pool area, with burning, is substantially smaller than for the without burning case because of the higher mass loss rate from the surface pool due to burning. Since the vessel speed substantially exceeds the spill spreading rate, both the thermal radiation fields and surface pool trail the vessel. The relative directions and speeds of the wind and vessel movement govern the orientation of the dispersed plume. If the vessel stops, the areas of the surface pool and incident radiation field (with burning) are maximized and the dispersed cloud area (without burning) minimized. The longer the delay in stopping the vessel, the smaller the peak values are for the pool area and the size of the thermal radiation field. Once the vessel stops, the spill pool is adjacent to the vessel and moving down current. The thermal radiation field is oriented similarly. These results may be particularly useful in contingency planning for underway vessels. PMID:17110025

Spaulding, Malcolm L; Swanson, J Craig; Jayko, Kathy; Whittier, Nicole

2006-10-21

46

LNG annotated bibliography  

SciTech Connect

This document updates the bibliography published in Liquefied Gaseous Fuels Safety and Environmental Control Assessment Program: third status report (PNL-4172) and is a complete listing of literature reviewed and reported under the LNG Technical Surveillance Task. The bibliography is organized alphabetically by author.

Bomelburg, H.J.; Counts, C.A.; Cowan, C.E.; Davis, W.E.; DeSteese, J.G.; Pelto, P.J.

1982-09-01

47

Coaxial piping system devised as LNG spill prevention solution  

SciTech Connect

A functional, dual containment system that contains piping spools that are coaxial in construction and components, fittings, unique valving arrangements, and engineering features that improve reliability, safety, and economics of hazardous and cryogenic fluid transfer and containment is described. The purpose is to improve reliability for liquefied natural gas (LNG) transfer and spill prevention. Elements of the system are inner and outer concentric pipe spool pieces; a spider element which holds the 2 pipes in coaxial relationship to each coupling by allowing vapor flow between the pipes; and an external insulation jacket. A qualified coaxial piping system is a viable solution for existing and new LNG facility transfer systems subject to regulatory enforcement.

Pfenning, T.E.

1982-12-01

48

Enhanced reflection via phase compensation from anomalous dispersion in atomic vapor  

SciTech Connect

The phase compensation mechanism induced by anomalous dispersion in the reflection process of four-wave mixing (or reflection from a grating) in a three-level system is investigated, where the four wave vectors do not match in vacuum. An efficiency of the reflected signal of as high as 43% from a hot atomic cell of Cs is observed. The maximum reflection occurs when the frequency of the probe beam (and consequently the frequency of the reflected signal) is slightly red detuned from the transition frequency, which is attributed to the phase compensation from the steep anomalous dispersion accompanied with a strong probe absorption. The dependences of the efficiency on the angle between the coupling and probe lights, on the intensity of the coupling, field and on atomic density are studied. A theoretical model is presented and it is in good agreement with the experimental results.

Zhang Junxiang; Zhou Haitao [State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006 (China); Wang Dawei [Beijing Computational Science Research Center, Beijing 100084 (China); Zhu Shiyao [State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006 (China); Beijing Computational Science Research Center, Beijing 100084 (China); Department of Physics, Hong Kong Baptist University (Hong Kong)

2011-05-15

49

75 FR 20591 - AES Sparrows Point LNG, LLC and Mid-Atlantic Express, LLC; Notice of Final General Conformity...  

Federal Register 2010, 2011, 2012, 2013

...Three 160,000 m\\3\\ (net capacity) full-containment LNG storage tanks; A closed-loop shell and tube heat exchanger vaporization system; Various ancillary facilities including administrative offices, warehouse, main control room,...

2010-04-20

50

75 FR 11169 - AES Sparrows Point LNG, LLC; Mid-Atlantic Express, LLC; Notice of Availability of the Revised...  

Federal Register 2010, 2011, 2012, 2013

...Three 160,000 m\\3\\ (net capacity) full-containment LNG storage tanks; A closed-loop shell and tube heat exchanger vaporization system; Various ancillary facilities including administrative offices, warehouse, main control room,...

2010-03-10

51

Polymer-dispersed liquid crystal doped with carbon nanotubes for dimethyl methylphosphonate vapor-sensing application  

NASA Astrophysics Data System (ADS)

This paper proposes a sensitive gas sensor composed of polymer-dispersed liquid crystal (PDLC) for dimethyl methylphosphonate (DMMP) detection. The sensing element comprises a PDLC sensing film doped with carbon nanotubes (CNT-PDLC) and a planar interdigital electrode pair. The concentration of DMMP exposed to the CNT-PDLC material is detectable by measuring the change in conductivity of the material. Compared to conventional LC-based sensors, the proposed PDLC device is robust against mechanical shocks, and can fully operate with a simple read-out circuit. The sensor response is linear for gas concentrations from 5 to 250 ppm, and the response time is approximately 125 s.

Lai, Yu-Tse; Kuo, Jui-Chang; Yang, Yao-Joe

2013-05-01

52

California offshore LNG port feasible  

Microsoft Academic Search

An offshore facility for liquefied natural gas (LNG) has been declared technologically and economically feasible by the California Coastal Commission, which is also charged with selecting the best onshore site. The Commission chose an offshore site in Ventura County on the basis of its remoteness and fewer potential environmental impacts. An offshore LNG terminal is estimated to cost in the

Murnane

1978-01-01

53

Liquefied Natural Gas (LNG) dispenser verification device  

NASA Astrophysics Data System (ADS)

The composition of working principle and calibration status of LNG (Liquefied Natural Gas) dispenser in China are introduced. According to the defect of weighing method in the calibration of LNG dispenser, LNG dispenser verification device has been researched. The verification device bases on the master meter method to verify LNG dispenser in the field. The experimental results of the device indicate it has steady performance, high accuracy level and flexible construction, and it reaches the international advanced level. Then LNG dispenser verification device will promote the development of LNG dispenser industry in China and to improve the technical level of LNG dispenser manufacture.

Xiong, Maotao; Yang, Jie-bin; Zhao, Pu-jun; Yu, Bo; Deng, Wan-quan

2013-01-01

54

Improved cyclic oxidation resistance of electron beam physical vapor deposited nano-oxide dispersed ?-NiAl coatings for Hf-containing superalloy  

Microsoft Academic Search

Oxide dispersed (OD) ?-NiAl coatings and OD-free ?-NiAl coatings were deposited onto a Hf-containing Ni-based superalloy by electron beam physical vapor deposition (EB-PVD). Excessive enrichment of Hf was found in the TGO on the OD-free coating due to outward diffusion of Hf from the superalloy, causing accelerated TGO thickening and spalling. The OD-coating effectively prevented Hf from outward diffusion. Only

Hongbo Guo; Yongjing Cui; Hui Peng; Shengkai Gong

2010-01-01

55

Hazards to nuclear power plants from large liquefied natural gas (LNG) spills on water  

SciTech Connect

The hazards to nuclear power plants arising from large spills of liquefied natural gas (LNG) on water transportation routes are treated by deterministic analytical procedures. Global models, which address the salient features of the LNG spill phenomena are used in the analysis. A coupled computational model for the combined LNG spill, spreading, and fire scenario is developed. To predict the air blast environment in the vicinity of vapor clouds with pancake-like geometries, a scalable procedure using both analytical methods and hydrocode calculations is synthesized. Simple response criteria from the fire and weapons effects literature are used to characterize the susceptibility of safety-related power plant systems. The vulnerability of these systems is established either by direct comparison between the LNG threat and the susceptibility criteria or through simple response calculations. Results are analyzed.

Kot, C.A.; Eichler, T.V.; Wiedermann, A.H.; Pape, R.; Srinivasan, M.G.

1981-11-01

56

LNG plants in the US and abroad. [Liquefied Natural Gas (LNG)  

Microsoft Academic Search

The Institute of Gas Technology recently conducted a comprehensive survey of LNG production and storage facilities in North America. This survey was performed as part of IGT's LNG Observer newsletter which covers both domestic and international LNG news, reports on LNG related economics and statistics, and routinely conducts interviews with key industry leaders. In addition to providing consulting services to

C. F. Blazek; R. T. Biederman

1992-01-01

57

33 CFR 127.319 - LNG transfer.  

Code of Federal Regulations, 2013 CFR

...ensure thatâ (1) The marine transfer area for LNG is under the supervision...other assigned duties during the transfer operation; (2) Personnel transferring fuel or oily waste are not involved in LNG transfer; and (3) No vessels...

2013-07-01

58

Conditions leading to the formation of polymer thin layers with densely dispersed organic dyes using the vapor transportation method with vacuum technique  

NASA Astrophysics Data System (ADS)

The "vapor transportation method" with vacuum technique, developed previsouly in our laboratory, was used to form polymer thin layers with densely dispersed photochromic dyes on polystyrene (PS), poly(methyl methacrylate) (PMMA), and polymcarbonate (PC) substrates. The organic photochrmoic dye cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethane (CMTE) was used, and the rate of formation of the CMTE-conatining layer was as follows: PS > PC > PMMA. These observations are important for application of the present method to the formation of organic memory media for optical recording etc. These results also indicate that the formation rate is dependent on not only the chemical composition and the structure of the polymer substrate, but also on the treatment temperature. Optical density measurements of the CMTE-dispersed thin polymer films showed maximum values near the glass transition temperature (g) with increases in temperature of film formation. The Tg values of CMTE-dispersed polymers decreased rapidly after CMTE-dispersal into the polymer matrices, indicating that Tg values of the polymers are important parameters for investigation of the mechanism of formation of CMTE-dispersed layers on polymer substrates using the present method.

Mizokuro, Toshiko; Mochizuki, Hiroyuki; Yamamoto, Noritaka; Tanaka, Norio; Horiuchi, Shin; Tanigaki, Nobutaka; Hiraga, Takashi

2003-07-01

59

Use of TX100-dangled epoxy as a reactive noncovalent dispersant of vapor-grown carbon nanofibers in an aqueous solution.  

PubMed

The dispersion of carbon nanotubes (CNTs) into individual particles or small bundles has remained a vexing problem that limits the use of the excellent properties of CNTs in composite applications. Noncovalent functionalization is an attractive option for changing the interfacial properties of nanotubes because it does not destroy the nanotube grapheme structure. In this study, a new reactive copolymer, epoxy-toluene diisocyanate-Triton X-100 (EP-TDI-TX100) was successfully synthesized, which is shown to be highly effective in dispersing vapor-grown carbon nanofibers (VGCNFs) into individual or small bundles, as evidenced by transmission electron microscopy (TEM) and UV-vis absorption spectra. The strong ?-? interaction between VGCNFs and EP-TDI-TX100 was revealed by Raman spectra and the covalent reaction between curing agent was confirmed via Fourier transform infrared spectroscopy. For an effective dispersion, the optimum weight ratio of EP-TDI-TX100 to VGCNFs is 2:1. The maximum VGCNF concentration that can be homogeneously dispersed in an aqueous solution is approximately 0.64 mg/mL. The EP-TDI-TX100 molecules are adsorbed on the VGCNF surface and prevent reaggregation of VGCNFs, so that a colloidal stability of VGCNF dispersion can be maintained for 6 months. PMID:23116860

Dong, Yubing; Wang, Rui; Li, Shan; Yang, Hongbing; Du, Mingliang; Fu, Yaqin

2012-10-12

60

Recommended research on LNG safety  

SciTech Connect

The US Department of Energy (DOE) is conducting research on the safety and other environmental aspects of liquefied energy gases including liquefied natural gas (LNG). The effort reported here was conducted as part of the planning for further research into the safety aspects of transporting and storing LNG, with primary emphasis on public safety. Although the modern LNG industry has enjoyed excellent success in providing for safe operations, significant questions remain on the part of many, the expressions of which were intensified with the addition of marine-based LNG import terminals. Public safety with regard to large-scale importation of this fuel has received widespread attention in the US Congress, state legislatures, county and city governments, and from various individuals and public groups, with coverage in all the news media, including books published on the subject. The safety concerns have centered around the consequences to the public of a large spill of the cryogenic liquid from an ocean tanker or a larger storage tank, either of which might hold as much as 125,000 m/sup 3/ of LNG.

Carpenter, H.J.; Gilmore, F.R.

1981-03-01

61

Risks of LNG and LPG. [Review  

Microsoft Academic Search

Since the use of liquefied natural gas (LNG) and liquefied petroleum gases (LPG) as fuels is likely to increase and will certainly persist for some time to come, assessment of the safety of LNG\\/LPG systems will continue to draw attention and is quite likely to force continuing review of operating and design standards for LNG\\/LPG facilities. Scientific investigations to date

Fay

1980-01-01

62

Investigation of low-cost LNG vehicle fuel tank concepts. Final report  

SciTech Connect

The objective of this study was to investigate development of a low-cost liquid natural gas (LNG) vehicle fuel storage tank with low fuel boil-off, low tank pressure, and high safety margin. One of the largest contributors to the cost of converting a vehicle to LNG is the cost of the LNG fuel tank. To minimize heat leak from the surroundings into the low-temperature fuel, these tanks are designed as cryogenic dewars with double walls separated by an evacuated insulation space containing multi-layer insulation. The cost of these fuel tanks is driven by this double-walled construction, both in terms of materials and labor. The primary focus of the analysis was to try to devise a fuel tank concept that would allow for the elimination of the double-wall requirement. Results of this study have validated the benefit of vacuum/MLI insulation for LNG fuel tanks and the difficulty in identifying viable alternatives. The thickness of a non-vacuum insulation layer would have to be unreasonably large to achieve an acceptable non-venting hold time. Reasonable hold times could be achieved by using an auxiliary tank to accept boil-off vapor from a non-vacuum insulated primary tank, if the vapor in the auxiliary tank can be stored at high pressure. The primary focus of the analysis was to try to devise a fuel tank concept that allowed for the elimination of the double-wall requirement. Thermodynamic relations were developed for analyzing the fuel tank transient response to heat transfer, venting of vapor, and out-flow of either vapor or liquid. One of the major costs associated with conversion of a vehicle to LNG fuel is the cost of the LNG fuel tank. The cost of these tanks is driven by the cryogenic nature of the fuel and by the fundamental design requirements of long non-venting hold times and low storage pressure.

O`Brien, J.E.; Siahpush, A. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.

1998-02-01

63

Bubbles in liquids with phase transition—part 2: on balance laws for mixture theories of disperse vapor bubbles in liquid with phase change  

NASA Astrophysics Data System (ADS)

We study averaging methods for the derivation of mixture equations for disperse vapor bubbles in liquids. The carrier liquid is modeled as a continuum, whereas simplified assumptions are made for the disperse bubble phase. An approach due to Petrov and Voinov is extended to derive mixture equations for the case that there is a phase transition between the carrier liquid and the vapor bubbles in water. We end up with a system of balance laws for a multi-phase mixture, which is completely in divergence form. Additional non-differential source terms describe the exchange of mass, momentum and energy between the phases. The sources depend explicitly on evolution laws for the total mass, the radius and the temperature of single bubbles. These evolution laws are derived in a prior article (Dreyer et al. in Cont Mech Thermodyn. doi: 10.1007/s00161-0225-6 , 2011) and are used to close the system. Finally, numerical examples are presented.

Dreyer, Wolfgang; Hantke, Maren; Warnecke, Gerald

2013-08-01

64

Potential Application of Floating LNG  

Microsoft Academic Search

The paper describes the efficiency of LNG and its contribution to world energy resources. It also examines the political, economical and technical drivers for successful realization of offshore liquefaction vessel development, main challenges and risks associated with it; it also reviews the current status of technology development and projects which are under development today. Objective: This paper seeks to identify

Elena Voskresenskaya

65

Assessing LNG tank volume calibrations  

Microsoft Academic Search

The National Bureau of Standards (NBS) is cooperating with others to develop measuring techniques and establish calibration standards for liquefied natural gas (LNG) tankers. A photogrammetric survey technique is now used to determine the volume of each tank, but there are errors inherent in the method that could be very costly. NBS checks of the photographic method are described and

K. Higgins; M. Baum

1979-01-01

66

United States LNG trade potential  

Microsoft Academic Search

Any assessment of the potential for U.S. liquefied natural gas imports made after February 26, 1976, must take into account the 1 trillion CF\\/yr limit on such imports proposed by President Ford in his energy message to Congress of that date. Specifically, the message called for increasing LNG imports to supplement declining supplies of domestic natural gas but also for

P. J. Anderson; E. J. Daniels

1976-01-01

67

On the application of computational fluid dynamics codes for liquefied natural gas dispersion.  

SciTech Connect

Computational fluid dynamics (CFD) codes are increasingly being used in the liquefied natural gas (LNG) industry to predict natural gas dispersion distances. This paper addresses several issues regarding the use of CFD for LNG dispersion such as specification of the domain, grid, boundary and initial conditions. A description of the k-{var_epsilon} model is presented, along with modifications required for atmospheric flows. Validation issues pertaining to the experimental data from the Burro, Coyote, and Falcon series of LNG dispersion experiments are also discussed. A description of the atmosphere is provided as well as discussion on the inclusion of the Coriolis force to model very large LNG spills.

Luketa-Hanlin, Anay Josephine; Koopman, Ronald P. (Lawrence Livermore National Laboratory, Livermore, CA); Ermak, Donald (Lawrence Livermore National Laboratory, Livermore, CA)

2006-02-01

68

49 CFR 193.2181 - Impoundment capacity: LNG storage tanks.  

Code of Federal Regulations, 2010 CFR

...Design and Capacity § 193.2181 Impoundment capacity: LNG storage tanks. Each impounding system serving an LNG storage tank must have a minimum volumetric liquid impoundment capacity of: (a) 110 percent of the LNG tank's maximum...

2009-10-01

69

49 CFR 193.2181 - Impoundment capacity: LNG storage tanks.  

Code of Federal Regulations, 2010 CFR

...Design and Capacity § 193.2181 Impoundment capacity: LNG storage tanks. Each impounding system serving an LNG storage tank must have a minimum volumetric liquid impoundment capacity of: (a) 110 percent of the LNG tank's maximum...

2010-10-01

70

49 CFR 193.2181 - Impoundment capacity: LNG storage tanks.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Impoundment capacity: LNG storage tanks. 193.2181 Section 193.2181...193.2181 Impoundment capacity: LNG storage tanks. Each impounding system serving an LNG storage tank must have a minimum volumetric...

2011-10-01

71

Space Averages of Air and Water Vapor Densities by Dispersion for Refractive Correction of Electromagnetic Range Measurements  

Microsoft Academic Search

The use of three-wavelength transit-time measurements is considered as a means of estimat- ing space averages of total density and water vapor density along a path through the lower atmosphere. The effects of instrumental errors ad of errors in estimating average path tem- perature are examined. The results indicate that, for what are considered reasonable pa.th conditions in this context,

Moody C. Thompson

1968-01-01

72

States urge LNG safety, siting rules; costs debated. [Regulation of LNG  

Microsoft Academic Search

The Federal Energy Administration held hearings at which several states urged the Federal government to adopt minimum standards for siting and safety rules for liquefied natural gas (LNG) in order to lower costs for LNG users. Spokesmen for the gas industry as well as state representatives were opposed to restrictions on LNG imports and rates based on incremental costs. The

1976-01-01

73

On the application of computational fluid dynamics codes for liquefied natural gas dispersion  

Microsoft Academic Search

Computational fluid dynamics (CFD) codes are increasingly being used in the liquefied natural gas (LNG) industry to predict natural gas dispersion distances. This paper addresses several issues regarding the use of CFD for LNG dispersion such as specification of the domain, grid, boundary and initial conditions. A description of the k–? model is presented, along with modifications required for atmospheric

Anay Luketa-Hanlin; Ronald P. Koopman; Donald L. Ermak

2007-01-01

74

Characterization of the Near-Field Transport and Dispersion of Vapors Released from the Headspaces of Hanford Site Underground Storage Tanks  

SciTech Connect

A parametric air dispersion analysis has been conducted to define the range of tank vapor concentrations from the Hanford Site underground tanks that can potentially occur in the worker breathing zones from active and passive releases from the waste tanks. The potential influences of tank farm specific release characteristics, ambient meteorological conditions, local farm surface roughness, and topographical influences are considered. The parametric approach allows consideration of the full range venting configurations and potential vapor concentration over the range of meteorological conditions at the Hanford Site. The results indicate that occasional short duration exposures of up to several seconds to relatively undiluted headspace air can be expected in the immediate vicinity of the tank vents. Average concentrations which represent diffusion, as well as spatial averaging, fall off rapidly with distance for the passive vents and to a lesser extent for the forced-air stacks. The addition of the influence of the surface roughness elements on the tank farms will result in a faster decrease of concentrations with downwind distance.

Droppo, James G.

2004-07-30

75

Dispersion of UO{sub 2}F{sub 2} aerosol and HF vapor in the operating floor during winter ventilation at the Paducah Gaseous Diffusion Plant  

SciTech Connect

The gaseous diffusion process is currently employed at two plants in the US: the Paducah Gaseous Diffusion Plant and the Portsmouth Gaseous Diffusion Plant. As part of a facility-wide safety evaluation, a postulated design basis accident involving large line-rupture induced releases of uranium hexafluoride (UF{sub 6}) into the process building of a gaseous diffusion plant (GDP) is evaluated. When UF{sub 6} is released into the atmosphere, it undergoes an exothermic chemical reaction with moisture (H{sub 2}O) in the air to form vaporized hydrogen fluoride (HF) and aerosolized uranyl fluoride (UO{sub 2}F{sub 2}). These reactants disperse in the process building and transport through the building ventilation system. The ventilation system draws outside air into the process building, distributes it evenly throughout the building, and discharges it to the atmosphere at an elevated temperature. Since air is recirculated from the cell floor area to the operating floor, issues concerning in-building worker safety and evacuation need to be addressed. Therefore, the objective of this study is to evaluate the transport of HF vapor and UO{sub 2}F{sub 2} aerosols throughout the operating floor area following B-line break accident in the cell floor area.

Kim, S.H.; Chen, N.C.J.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W. [Oak Ridge National Lab., TN (United States); Carter, J.C. [J.C. Carter Associates, Inc., Knoxville, TN (United States)

1996-12-30

76

Re-Examining the Properties of the Aqueous Vapor-Liquid Interface Using Dispersion Corrected Density Functional Theory  

SciTech Connect

First-principles molecular dynamics simulations, in which the forces are computed from electronic structure calculations, have great potential to provide unique insight into structure, dynamics, electronic properties, and chemistry at aqueous interfaces that is not available from empirical force fields. The majority of current first-principles simulations are driven by forces derived from density functional theory with generalized gradient approximations to the exchange-correlation energy, which do not capture dispersion interactions. We have carried out first-principles molecular dynamics simulations of air-water interfaces employing a particular generalized gradient approximation to the exchange-correlation functional (BLYP), with and without empirical dispersion corrections. We assess the utility of the dispersion corrections by comparison of a variety of structural, dynamic, and thermodynamic properties of bulk and interfacial water with experimental data, as well as other first-principles and force field-based simulations. This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

Baer, Marcel D.; Mundy, Christopher J.; McGrath, Matthew J.; Kuo, I-F W.; Siepmann, Joern I.; Tobias, Douglas J.

2011-09-28

77

Feasibility of methods and systems for reducng LNG tanker fire hazards  

SciTech Connect

In this program concepts for reducing fire hazards that may result from LNG tanker collisions are identified and their technical feasibility evaluated. Concepts considered include modifications to the shipborne LNG containers so that in the event of a container rupture less of the contents would spill and/or the contents would spill at a reduced rate. Changes in the cargo itself, including making the LNG into a gel, solidifying it, converting it to methanol, and adding flame suppressants are also evaluated. The relative effectiveness and the costs of implementing these methods in terms of increased cost of gas at the receiving terminal, are explained. The vulnerability of an LNG tanker and its crew to the thermal effects of a large pool fire caused by a collision spill is estimated and methods of protecting the crew are considered. It is shown that the protection of ship and crew so that further deterioration of a damaged ship might be ameliorated, would require the design and installation of extraordinary insulation systems and life support assistance for the crew. Methods of salvaging or disposing of cargo from a damaged and disabled ship are evaluated, and it is concluded that if the cargo cannot be transferred to another (empty) LNG tanker because of lack of availability, then the burning of the cargo at a location somewhat distant from the disabled tanker appears to be a promising approach. Finally, the likelihood of the vapors from a spill being ignited due to the frictional impact of the colliding ships was examined. It is found that the heating of metal sufficient to ignite flammable vapors would occur during a collision, but it is questionable whether flammable vapor and air will, in fact, come in contact with the hot metal surfaces.

Not Available

1980-08-01

78

Fire safety aboard LNG vessels. Final report  

Microsoft Academic Search

This reports results of an analytical examination of cargo spill and fire hazard potential associated with the marine handling of liquefied natural gas (LNG) cargo. Principal emphasis was on cargo transfer operations at receiving terminals, and more specifically, on the LNG tanker's cargo handling and hazard sensing and control equipment and operations. Analytical procedures included historical (statistical) analysis of failure

J. R. Welker; L. E. Brown; J. N. Ice; W. E. Martinsen; H. H. West

1976-01-01

79

Analysing the risk of LNG carrier operations  

Microsoft Academic Search

This paper presents a generic, high-level risk assessment of the global operation of ocean-going liquefied natural gas (LNG) carriers. The analysis collects and combines information from several sources such as an initial hazid, a thorough review of historic LNG accidents, review of previous studies, published damage statistics and expert judgement, and develops modular risk models for critical accident scenarios. In

Erik Vanem; Pedro Antão; Ivan Østvik; Francisco Del Castillo de Comas

2008-01-01

80

Cove Point LNG receiving terminal control systems  

Microsoft Academic Search

The control systems installed to operate the Cove Point LNG receiving terminal have performed exceptionally well, reports Columbia LNG Corp. All major equipment at the terminal is operated locally from manned monitoring stations that are linked via telemetry to the computer in the terminal's main control room. An independent emergency system, activated by designated pushbuttons located throughout the plants, automatically

Kazinoff

1979-01-01

81

Raley's LNG Truck Site Final Data Report.  

National Technical Information Service (NTIS)

Raley's is a 120-store grocery chain with headquarters in Sacramento, California, that has been operating eight heavy-duty LNG trucks (Kenworth T800 trucks with Cummins L10-300G engines) and two LNG yard tractors (Ottawa trucks with Cummins B5.9G engines)...

Battelle

1999-01-01

82

Grain structure and growth of dispersed phase BN-AlN coatings grown via chemical vapor deposition  

SciTech Connect

This paper discusses the variation in microstructures encountered during the separate depositions of boron nitride (BN) and aluminium nitride (AlN) as well as during the codeposition of BN-AlN dispersed phase ceramic coatings. This combination was chosen in order to take advantage of the self lubricating properties of hexagonal BN along with the hard, erosion resistance of AlN. Films were characterized using scanning and transmission electron microscopy (SEM and TEM), x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD). A range of coating microstructures are possible depending on the conditions of deposition. The best films produced, in terms of hardness, density, and tenacity, were a fine mixture of turbostratic BN and preferentially oriented A1N whiskers aligned with the whisker axis perpendicular to the substrate surface as seen by both electron microscopy and x-ray diffraction. 4 refs., 9 figs., 1 tab.

Freeman, G.B.; Lackey, W.J.; Hanigofsky, J.A. (Georgia Inst. of Tech., Atlanta, GA (USA). Georgia Technology Research Inst.); Lee, Woo Y. (United Technologies Research Center, East Hartford, CT (USA)); More, K.L. (Oak Ridge National Lab., TN (USA))

1990-01-01

83

Dispersive liquid liquid microextraction combined with electrothermal vaporization inductively coupled plasma mass spectrometry for the speciation of inorganic selenium in environmental water samples.  

PubMed

A novel method based on dispersive liquid liquid microextraction (DLLME) followed by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) determination was proposed for the speciation of inorganic selenium by using 5-mercapto-3-phenyl-1,3,4-thiadiazole-2-thione potassium salt (Bismuthiol II) as both chelating reagent and chemical modifier. In this method, 500?L ethanol (as disperser solvent) containing 70?L chloroform (as extraction solvent) and 0.2gL(-1) Bismuthiol II (as chelating reagent) was rapidly injected into a sample solution to form cloudy solution. The complex of Se(IV) with Bismuthiol II was rapidly extracted into the extraction solvent at pH 2.0, while Se(VI) was remained in the aqueous solutions. Thus, the separation of Se(IV) and Se(VI) could be realized. After centrifugation, the complex of Se(IV) and Bismuthiol II concentrated in the extraction solvent was introduced into the ETV-ICP-MS for determination of Se(IV). Se(VI) was reduced to Se(IV) prior to determination of total selenium, and its assay was based on subtracting Se(IV) from total selenium. The main factors influencing the DLLME and the vaporization behavior of selenium in ETV were investigated systematically. Under the optimal conditions, the limit of detection (LOD) for Se(IV) was 0.047ngmL(-1). The relative standard deviation (RSD) was 7.2% (CSe(IV)=1.0ngmL(-1), n=8) with an enhancement factor of 64.8-fold from only 5mL of water sample. The proposed method was successfully applied to the speciation of inorganic selenium in different environmental water samples with recoveries ranging from 94.8 to 108% for the spiking samples. In order to validate the proposed method, a Certified Reference Material of Environment Water (GBW(E)080395) was analyzed, and the determined value obtained was in good agreement with the certified value. PMID:24054655

Zhang, Yuan; Duan, Jiankun; He, Man; Chen, Beibei; Hu, Bin

2013-06-29

84

LNG importing project in Taiwan, ROC  

SciTech Connect

To cope with an ever-increasing demand for natural gas facing a dwindling indigenous supply and to follow the national policy of diversification of energy resources in the Republic of China, Chinese Petroleum Corporation (CPC) has launched its first LNG Receiving Terminal project at Yung-An, Kaohsiung for the importation of LNG to Taiwan. This paper presents selected design essentials and distinguished characteristics of this project. In pursuit of safety, operability and energy efficiency, the design and engineering of this facility features the following: Higher pressure LNG in-ground storage tanks. Application of recondensers for BOG in process. Integrated control system.

Liu, J.C.; Chung, S.T.; Shen, R.H.

1988-01-01

85

Raley's LNG Truck Site Final Data Report  

SciTech Connect

Raley's is a 120-store grocery chain with headquarters in Sacramento, California, that has been operating eight heavy-duty LNG trucks (Kenworth T800 trucks with Cummins L10-300G engines) and two LNG yard tractors (Ottawa trucks with Cummins B5.9G engines) since April 1997. This report describes the results of data collection and evaluation of the eight heavy-duty LNG trucks compared to similar heavy-duty diesel trucks operating at Raley's. The data collection and evaluation are a part of the U.S. Department of Energy (DOE)/National Renewable Energy Laboratory (NREL) Alternative Fuel Truck Evaluation Project.

Battelle

1999-07-01

86

77 FR 76013 - Sempra LNG Marketing, LLC; Application for Blanket Authorization To Export Previously Imported...  

Federal Register 2010, 2011, 2012, 2013

...FE Docket No. 12-155-LNG] Sempra LNG Marketing, LLC; Application for Blanket Authorization...filed on October 26, 2012, by Sempra LNG Marketing, LLC (Sempra LNG Marketing), requesting blanket authorization to...

2012-12-26

87

Operating history of Arun LNG Plant  

SciTech Connect

The Arun LNG plant is owned by PERTAMINA (The Oil And Gas State Enterprise Of The Republic Of Indonesia) and is located at Blang Lancang, North Aceh, Sumatra, Indonesia. It is about 15 km west of the port of Lhokseumawe, or about 300 km north-west of the city of Medan. The plant is operated by PT Arun NGL Co. The Arun LNG plant receives gas and unstabilized hydrocarbon condensate from the Arun Field gas reservoir which is developed and operated by MOBIL OIL INDONESIA under Production Sharing Contract with PERTAMINA and is located about 30 km south-east of the plant. The gas and condensate are transported by pipeline to the plant. Operation of the condensate recovery unit began in April 1977 and the three LNG trains began producing LNG in August 1978, September 1978 and February 1979 respectively. The original three-train plant now produces 34000 m/sup 3//day of LNG and 85000 bbl/day of condensate. An additional two LNG trains have been constructed and recently began production.

Suyanto, J.R.O.

1984-02-01

88

Keys to modeling LNG spills on water.  

PubMed

Although no LNG ship has experienced a loss of containment in over 40 years of shipping, it is important for risk management planning to understand the predicted consequences of a spill. A key parameter in assessing the impact of an LNG spill is the pool size. LNG spills onto water generally result in larger pools than land spills because they are unconfined. Modeling of LNG spills onto water is much more difficult than for land spills because the phenomena are more complex and the experimental basis is more limited. The most prevalent practice in predicting pool sizes is to treat the release as instantaneous or constant-rate, and to calculate the pool size using an empirical evaporation or burn rate. The evaporation or burn rate is particularly difficult to estimate for LNG spills on water, because the available data are so limited, scattered, and difficult to extrapolate to the large releases of interest. A more effective modeling of possible spills of LNG onto water calculates, rather than estimating, the evaporation or burn rate. The keys to this approach are to: * Use rigorous multicomponent physical properties. * Use a time-varying analysis of spill and evaporation. * Use a material and energy balance approach. * Estimate the heat transfer from water to LNG in a way that reflects the turbulence. These keys are explained and demonstrated by predictions of a model that incorporates these features. The major challenges are describing the effects of the LNG-water turbulence and the heat transfer from the pool fire to the underlying LNG pool. The model includes a fundamentally based framework for these terms, and the current formulation is based on some of the largest tests to-date. The heat transfer coefficient between the water and LNG is obtained by applying a "turbulence factor" to the value from correlations for quiescent film and transition boiling. The turbulence factor is based on two of the largest unignited tests on water to-date. The heat transfer from the fire to the pool is based on the burning rate for the largest pool fire test on land to-date. PMID:17113709

Hissong, D W

2006-10-20

89

49 CFR 193.2623 - Inspecting LNG storage tanks.  

Code of Federal Regulations, 2012 CFR

...AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2623 Inspecting LNG storage tanks. Each LNG...

2012-10-01

90

49 CFR 193.2623 - Inspecting LNG storage tanks.  

Code of Federal Regulations, 2010 CFR

...NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2623 Inspecting LNG storage tanks. Each LNG storage tank must be inspected or tested to verify that each of the following conditions does not impair the structural...

2010-10-01

91

LNG shipments in 1994 set records  

SciTech Connect

Worldwide LNG shipments by ocean-going vessels in 1994 increased to 1,619 voyages, according to an LNG shipping industry statistical annual. LNG Log 20 published the recently compiled 1994 data in the last quarter of 1995. The publication is from the Society of International Gas Tanker and Terminal Operators Ltd., London. The year`s total was 8.8% more than for 1993 and the most in 35 years of records. The trips were made and the vessels loaded and discharged without report of serious safety or environmental incident, says the publication. Of the voyages completed during the year, 596 were to European receiving terminals (up 2.8% over 1993), and 1,003 went to the Far East (an increase of 10.7%); shipments to the US, however, dropped to 20, from 32 in 1993. This paper shows that the 1,619 voyages represent 3.6 million nautical miles logged by 78 vessels active during the year. These ships pumped ashore record annual volumes of approximately 144.3 million cu m of LNG, 110.1 million cu m (76.3%) of which went to Far Eastern customers. The paper also summarizes containment systems in use in 1994 and since LNG began to be shipped in 1959.

NONE

1996-01-15

92

Safety and Risk Management of Large LNG Spills Over Water  

Microsoft Academic Search

The increasing demand for natural gas in the U.S. could significantly increase the number and frequency of marine LNG (Liquefied Natural Gas) imports. While many studies have been conducted to assess the consequences and risks of potential LNG spills, the increasing importance of LNG imports suggests that consistent methods and approaches be identified and implemented to help ensure protection of

Michael Hightower

93

Safety implications of a large LNG tanker spill over water  

Microsoft Academic Search

The increasing demand for natural gas in the United States could significantly increase the number and frequency of marine LNG (liquefied natural gas) imports. Although many studies have been conducted to assess the consequences and risks of potential LNG spills, the increasing importance of LNG imports suggests that consistent methods and approaches be identified and implemented to help ensure protection

Marion Michael Hightower; Louis Alan Gritzo; Anay Josephine Luketa-Hanlin

2005-01-01

94

Industry will pay most of Algeria LNG price hike  

Microsoft Academic Search

Industrial users will pay most of the fivefold incremental price increase in Algerian liquefied natural gas (LNG) recently approved by the Economic Regulatory Administration (ERA). The three affected gas-importing companies - Columbia LNG Corp., Consolidated LNG corp., and Southern Energy Co. - are major suppliers for eastern and southern states. They will be paying $1.94 per million Btu (mmBtu) (increase

1980-01-01

95

Study on the Representative LNG Sampling for Property Measurement.  

National Technical Information Service (NTIS)

The calorific value of LNG is very important factor for the quality and the price of imported LNG. But it is impossible to measure the composition of total amount of imported LNG. So, KGC uses the sampling method to represent the total amount of imported ...

K. Y. Choe K. C. Ryu

1994-01-01

96

Analysis of liquefied natural gas (LNG) release prevention systems  

Microsoft Academic Search

Liquefied Natural Gas (LNG) is playing an important role in meeting the energy needs of the U.S. and other countries. Since one unit volume of LNG is equivalent to 600 unit volumes of natural gas, liquefaction permits large volumes of gas to be economically stored and transported. In the United States, LNG has a twenty-year record of safe handling and

P. J. Pelto; E. G. Baker

1984-01-01

97

49 CFR 193.2623 - Inspecting LNG storage tanks.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Inspecting LNG storage tanks. 193.2623 Section 193.2623 Transportation...STANDARDS Maintenance § 193.2623 Inspecting LNG storage tanks. Each LNG storage tank must be inspected or tested to verify...

2011-10-01

98

Problems and solutions for pipelining LNG  

SciTech Connect

This paper discusses an engineering program and a test program to prove a suitable pipe structure for LNG transport, performed in collaboration with European official organizations, petroleum companies, pipe and material manufacturers, pipe insulators, and contractors. It reveals that new technical solutions have been found to determine mechanical stresses due to pipe shrinkage, to ease the construction of pipe sections, and to accelerate the construction work progress. Results of technical and economical approaches showed that high-capacity, long-distance LNG lines may be suitable to long-distance gas lines. The fact that the need for cold power (as supplied by LNG pipelines) of various industries is significant is outlined. The main disadvantages of cryogenic lines is the low operating temperatures which require the use of high cost nickel steel, and the need for a highly efficient insulation to reduce the thermal exchange through the pipe structure.

Tuyen, N.V.; Regnaud, P.

1983-01-24

99

Safety implications of a large LNG tanker spill over water.  

SciTech Connect

The increasing demand for natural gas in the United States could significantly increase the number and frequency of marine LNG (liquefied natural gas) imports. Although many studies have been conducted to assess the consequences and risks of potential LNG spills, the increasing importance of LNG imports suggests that consistent methods and approaches be identified and implemented to help ensure protection of public safety and property from a potential LNG spill. For that reason the U.S. Department of Energy (DOE), Office of Fossil Energy, requested that Sandia National Laboratories (Sandia) develop guidance on a risk-based analysis approach to assess and quantify potential threats to an LNG ship, the potential hazards and consequences of a large spill from an LNG ship, and review prevention and mitigation strategies that could be implemented to reduce both the potential and the risks of an LNG spill over water. Specifically, DOE requested: (1) An in-depth literature search of the experimental and technical studies associated with evaluating the safety and hazards of an LNG spill from an LNG ship; (2) A detailed review of four recent spill modeling studies related to the safety implications of a large-scale LNG spill over water; (3) Evaluation of the potential for breaching an LNG ship cargo tank, both accidentally and intentionally, identification of the potential for such breaches and the potential size of an LNG spill for each breach scenario, and an assessment of the potential range of hazards involved in an LNG spill; (4) Development of guidance on the use of modern, performance-based, risk management approaches to analyze and manage the threats, hazards, and consequences of an LNG spill over water to reduce the overall risks of an LNG spill to levels that are protective of public safety and property.

Hightower, Marion Michael; Gritzo, Louis Alan; Luketa-Hanlin, Anay Josephine

2005-04-01

100

LNG links remote supplies and markets  

Microsoft Academic Search

Liquefied natural gas (LNG) has established a niche for itself by matching remote gas supplies to markets that both lacked indigenous gas reserves and felt threatened in the aftermath of the energy crises of the 1970s and 1980s. It has provided a cost-effective energy source for these markets, while also offering an environmentally friendly fuel long before that was fashionable.

A. A. Avidan; R. E. Gardner; D. Nelson; E. N. Borrelli; T. J. Rethore

1997-01-01

101

Development of LNG Facilities Safety Standards  

Microsoft Academic Search

This paper examines a set of safety regulations adopted by the California Public Utilities Commission entitled ''Liquefied Natural Gas Facilities Safety Standards.'' The standards prescribe rules governing the design, construction, and safety aspects of the operation and maintenance of LNG facilities in California. These regulations are the most comprehensive in the United States today.

Ony

1985-01-01

102

Accident at the Cove Point LNG facility  

Microsoft Academic Search

On October 6, 1979, an explosion occurred at the Cove Point, Md, liquefied natural gas receiving terminal when leaking LNG was ignited by an electrical arc. The explosion destroyed an electrical substation building containing switchgear and motor controllers. This paper briefly describes the accident itself, the source of the gas leakage and cause of the explosion. Details of the seal

Van Meerbeke

1982-01-01

103

LNG fleet increases in size and capabilities  

SciTech Connect

The LNG fleet as of early 1997 consisted of 99 vessels with total cargo capacity of 10.7 million cu m, equivalent to approximately 4.5 million tons. One of the newest additions to the fleet, the 137,000-cu m tanker Al Zubarah, is five times the size of the original commercial vessel Methane Princess. Al Zubarah`s first loading of more than 60,000 tons occurred in December 1996 for deliver to Japanese buyers from the newly commissioned Qatargas LNG plant at Ras Laffan. That size cargo contains enough clean-burning energy to heat 60,000 homes in Japan for 1 month. Measuring nearly 1,000 ft long, the tanker is among the largest in the industry fleet and joined 70 other vessels of more than 100,000 cu m. Most LNG tankers built since 1975 have been larger-capacity vessels. The paper discusses LNG shipping requirements, containment systems, vessel design, propulsion, construction, operations and maintenance, and the future for larger vessels.

Linser, H.J. Jr.; Drudy, M.J.; Endrizzi, F.; Urbanelli, A.A. [Mobil Shipping and Transportation, Fairfax, VA (United States)

1997-06-02

104

Impact analysis of LNG carrier modelling systems  

Microsoft Academic Search

Global energy demand especially natural gas is expected to grow due to high world oil prices. Natural gas composed mostly of methane is the cleanest burning fossil fuel. Thus, offering an alternative fuel and at the same time has ability to reduces the environment impact. LNG carrier has been successfully used to transport this fuel across the globe, despite being

M. R. Zoolfakar; E. Mesbahi; R. Norman

2011-01-01

105

Siting hazardous facilities: lessons from LNG  

Microsoft Academic Search

This paper develops a descriptive framework for siting large scale technological facilities such as liquefied natural gas (LNG) terminals, and suggests ways of using analyses to improve the process. A key feature of these problems is that they involve relatively new technologies where there has not been a long history with which to construct a statistical data base. Hence the

Howard Kunreuther; John W. Lathrop

1981-01-01

106

U.S. LNG Imports - The Next Wave  

EIA Publications

U.S. LNG imports - The Next Wave, is now available as a special supplement to the January 2007 issue of the Short-Term Energy Outlook (STEO). Although liquefied natural gas (LNG) imports still account for less than three percent of total U.S. natural gas supplies, the global market is growing and the Energy Information Administration (EIA) foresees another wave of U.S. LNG import growth over the next 2 years. The supplement focuses on recent trends in global and U.S. LNG trade, and presents factors expected to influence LNG imports through 2008. EIA expects year-over-year increases in LNG imports of 34.5 and 38.5 percent in 2007 and 2008, respectively.

Information Center

2007-01-11

107

Exergy recovery during LNG regasification: Electric energy production – Part two  

Microsoft Academic Search

In liquefied natural gas (LNG) regasification facilities, for exergy recovery during regasification, an option could be the production of electric energy recovering the energy available as cold. In a previous paper, the authors propose an innovative process which uses a cryogenic stream of LNG during regasification as a cold source in an improved combined heat and power (CHP) plant. Considering

Celidonio Dispenza; Giorgio Dispenza; Vincenzo La Rocca; Giuseppe Panno

2009-01-01

108

Key Technologies of Mitsubishi LNG Carriers - Present and Future  

Microsoft Academic Search

CO2 emission control is recognized as the essential issue related to the greenhouse effect, especially since demand for energy increasing. Use of Liquefied Natural Gas (LNG) must be expanded because it produces less CO2 emission than any other fossil fuel. Worldwide, approximately 90 million tons of LNG are transported by sea in 1999. Mitsubishi Heavy Industries, Ltd. (MHI) has developed

Kazuaki Yuasa; Katsuya Uwatoko; Junshiro Ishimaru

109

Economics of the LNG Value Chain and Corporate Strategies  

Microsoft Academic Search

Abstract This paper analyzes corporate strategies in the emerging global LNG industry. In particular, we provide an empirical analysis of the ,determinants driving companies ,towards increasing vertical integration – a typical corporate behavior currently observable. Our hypothesis of high ,transaction costs along the LNG value chain inducing a higher degree of vertical integration is tested by implementing,an Ordered Probit Model.

Sophia Rüster; Anne Neumann

110

Model of spills and fires from LNG and oil tankers  

Microsoft Academic Search

A comprehensive model for predicting the dynamics of spills from LNG and oil product tankers is constructed from fluid mechanics principles and empirical properties of oil and LNG spills on water. The analysis utilizes the significant tanker hold and discharge flow area dimensions to specify the cargo liquid outflow history and the ensuing pool characteristics, including the establishment of a

J. A. Fay

2003-01-01

111

Early Commitment and Entry Deterrence in an LNG Shipping Market  

Microsoft Academic Search

The LNG (Liquefied Natural Gas) trade is one of the most promising sectors in energy shipping. An impor- tant characteristic of the LNG shipping market is its oligopolistic structure. The market actors make their decisions independently, yet knowing that these deci- sions are likely to influence the strategic positioning of the other players. This context is appropriate for the adoption

Konstantinos G. Gkonis; Harilaos N. Psaraftis

112

Imported LNG (liquid natural gas) as an alternative fuel  

Microsoft Academic Search

Imports of liquefied natural gas (LNG) first arrived in the United States in 1972 at the rate of one billion cubic feet (Bcf) per year. By 1979, they had reached 252 Bcf\\/year. However, as US as demand declined and domestic deliverability grew, inflexible LNG prices led to the complete collapse of trade during the 1980s. In 1987, all four US

1990-01-01

113

Development of a Dispersion-Strengthened Superalloy.  

National Technical Information Service (NTIS)

Two methods were compared for preparing oxide-dispersion-strengthened superalloys. Alloy powders containing dispersed oxides were prepared by the selective reduction of spray-dried mixtures and also by vapor deposition of matrix metal onto dispersoid part...

R. F. Cheney W. Scheithauer

1967-01-01

114

LNG (liquefied natural gas): A necessary part in China's future energy infrastructure  

Microsoft Academic Search

This paper presents an overview of the LNG industry in China, covering LNG plants, receiving terminals, transportation, and applications. Small and medium scale LNG plants with different liquefaction processes have already been built or are being built. China's first two LNG receiving terminals have been put into operation in Guangdong and Fujian, another one is being built in Shanghai, and

Wensheng Lin; Na Zhang; Anzhong Gu

2010-01-01

115

A survey of LNG technological needs in the USA: 1974 to beyond 2000  

Microsoft Academic Search

A comprehensive analysis of research needs of liquefied natural gas (LNG) was conducted. LNG research priorities for five years are considered vital to overcome the potential suppression of growth in the LNG industry that could result from lack of available technology. A survey of National Bureau of Standards LNG research and how these relate to the future technological growth of

L. A. Sarkes; D. B. Mann

1974-01-01

116

VAPOR VALVE  

DOEpatents

Electromagnetically operated vapor valves are described for apparatus employed in the separation of isotopes or elements to control the flow of gaseous vapors between a vaporizing charge chamber and an ionizing chamber, The charge chamber and ionizing chamber are positioned in a magnetic field, and the flow of vapors through an orifice connecting the chambers is regulated by regulating the flow of current through a resilient metal strip rigidly mounted at one end and positioned in the magnetic field adjacent to the orifice.

Wouters, L.F.

1959-08-25

117

Model of spills and fires from LNG and oil tankers.  

PubMed

A comprehensive model for predicting the dynamics of spills from LNG and oil product tankers is constructed from fluid mechanics principles and empirical properties of oil and LNG spills on water. The analysis utilizes the significant tanker hold and discharge flow area dimensions to specify the cargo liquid outflow history and the ensuing pool characteristics, including the establishment of a pool fire. The pool fire area, duration, and heat release rate are determined as functions of the tanker cargo variables. Examples of an LNG and gasoline spill show that for likely discharge flow areas these spills may be regarded as instantaneous, simplifying the evaluation of risk consequences. PMID:12493207

Fay, J A

2003-01-31

118

Vapor-phase photo-oxidation of methanol over nanosize titanium dioxide clusters dispersed in MCM-41 host material part 1: synthesis and characterization.  

PubMed

Nanosize clusters of titania were dispersed in mesoporous MCM-41 silica matrix with the help of the incipient wet-impregnation route, using an isopropanol solution of titanium isopropoxide as precursor. The clusters thus formed were of pure anatase phase and their size depended upon the titania loading. In the case of low (< 15 wt %) loadings, the TiO2 particles were X-ray and laser-Raman amorphous, confirming very high dispersion. These particles were mostly of < or = 2 nm size. On the other hand, larger size clusters (2-15 nm) were present in a sample with a higher loading of approximately 21 wt %. These particles of titania, irrespective of their size, exhibited an absorbance behavior similar to that of bulk TiO2. Powder X-ray diffraction, N2-adsorption and transmission electron microscopy results showed that while smaller size particles were confined mostly inside the pore system, the larger size particles occupied the external surface of the host matrix. At the same time, the structural integrity of the host was maintained even though some deformation in the pore system was noticed in the case of the sample having highest loading. The core level X-ray photoelectron spectroscopy results revealed a + 4 valence state of Ti in all the samples. A positive binding energy shift and the increase of the width of Ti 2p peaks were observed, however, with the decrease in the particle size of supported titania crystallites, indicative of a microenvironment for surface sites that is different from that of the bulk. PMID:16010941

Bhattacharya, K; Tripathi, A K; Dey, G K; Gupta, N M

2005-05-01

119

Safety of cargo handling and transport liquefied natural gas by sea. Dangerous properties of LNG and actual situation of LNG Fleet  

Microsoft Academic Search

Natural gas becomes very important source of energy. There is only one economical solution of transport natural gas to distant destination - LNG - Liquefied Natural Gas. The LNG fleet is growing very fast and fleet characteristic is changing. Very popular is myth that gas carriers are sailing bombs - is it true? Properties of LNG compare with other liquid

A. Starosta

120

Environmental Assessment for an LNG Spill Test Facility.  

National Technical Information Service (NTIS)

Lawrence Livermore National Laboratory has assessed the environmental effects of a proposed LNG (liquefied natural gas) spill test program involving the construction of a temporary experimental spill test facility. The major objective of this environmenta...

W. C. O'Neal W. J. Hogan

1981-01-01

121

Numerical Simulation and Optimazation of Small Scale LNG Plant  

NASA Astrophysics Data System (ADS)

The LNG20 is a small-scale natural gas liquefier. Its capacity is 20 cube meters LNG per day. This liquefier could be used for the pipeline gas, coalbed gas, oil field gas liquefaction and peakshaving plant for town gas gate station and natural gas power plant. Two processing cycles are applied to LNG20, nitrogen expander cycle and mixed refrigerant cycle. In this report, two feed gases are the target sources; one is the pipeline gas in ``West-to-east pipeline gas'' in a gate station in Zhejiang province and coalbed gas in Northeast China. The numerical simulation and optimization for the LNG20 were carried out to obtain the design parameters.

Li, H. Y.; Jia, L. X.; Fan, Q. H.; Yin, Q. S.

2006-04-01

122

The Phoenix series large scale LNG pool fire experiments.  

SciTech Connect

The increasing demand for natural gas could increase the number and frequency of Liquefied Natural Gas (LNG) tanker deliveries to ports across the United States. Because of the increasing number of shipments and the number of possible new facilities, concerns about the potential safety of the public and property from an accidental, and even more importantly intentional spills, have increased. While improvements have been made over the past decade in assessing hazards from LNG spills, the existing experimental data is much smaller in size and scale than many postulated large accidental and intentional spills. Since the physics and hazards from a fire change with fire size, there are concerns about the adequacy of current hazard prediction techniques for large LNG spills and fires. To address these concerns, Congress funded the Department of Energy (DOE) in 2008 to conduct a series of laboratory and large-scale LNG pool fire experiments at Sandia National Laboratories (Sandia) in Albuquerque, New Mexico. This report presents the test data and results of both sets of fire experiments. A series of five reduced-scale (gas burner) tests (yielding 27 sets of data) were conducted in 2007 and 2008 at Sandia's Thermal Test Complex (TTC) to assess flame height to fire diameter ratios as a function of nondimensional heat release rates for extrapolation to large-scale LNG fires. The large-scale LNG pool fire experiments were conducted in a 120 m diameter pond specially designed and constructed in Sandia's Area III large-scale test complex. Two fire tests of LNG spills of 21 and 81 m in diameter were conducted in 2009 to improve the understanding of flame height, smoke production, and burn rate and therefore the physics and hazards of large LNG spills and fires.

Simpson, Richard B.; Jensen, Richard Pearson; Demosthenous, Byron; Luketa, Anay Josephine; Ricks, Allen Joseph; Hightower, Marion Michael; Blanchat, Thomas K.; Helmick, Paul H.; Tieszen, Sheldon Robert; Deola, Regina Anne; Mercier, Jeffrey Alan; Suo-Anttila, Jill Marie; Miller, Timothy J.

2010-12-01

123

Aussie LNG players target NE Asia in expansion bid  

SciTech Connect

Australia's natural gas players, keen to increase their presence in world liquefied natural gas trade, see Asia as their major LNG market in the decades to come. That's despite the fact that two spot cargoes of Australian Northwest Shelf LNG were shipped to Europe during the last 12 months and more are likely in 1994. Opportunities for growth are foreseen within the confines of the existing Northwest Shelf gas project for the rest of the 1990s. But the main focus for potential new grassroots project developers and expansions of the existing LNG plant in Australia is the expected shortfall in contract volumes of LNG to Japan, South Korea, and Taiwan during 2000--2010. Traditionally the price of crude oil has been used as a basis for calculating LNG prices. This means the economics of any new 21st century supply arrangements are delicately poised because of the current low world oil prices, a trend the market believes is likely to continue. In a bid to lessen the effect of high initial capital outlays and still meet projected demand using LNG from new projects and expansion of the existing plant, Australia's gas producers are working toward greater cooperation with prospective Asian buyers.

Not Available

1994-02-28

124

LNG cascading damage study. Volume I, fracture testing report.  

SciTech Connect

As part of the liquefied natural gas (LNG) Cascading Damage Study, a series of structural tests were conducted to investigate the thermal induced fracture of steel plate structures. The thermal stresses were achieved by applying liquid nitrogen (LN{sub 2}) onto sections of each steel plate. In addition to inducing large thermal stresses, the lowering of the steel temperature simultaneously reduced the fracture toughness. Liquid nitrogen was used as a surrogate for LNG due to safety concerns and since the temperature of LN{sub 2} is similar (-190 C) to LNG (-161 C). The use of LN{sub 2} ensured that the tests could achieve cryogenic temperatures in the range an actual vessel would encounter during a LNG spill. There were four phases to this test series. Phase I was the initial exploratory stage, which was used to develop the testing process. In the Phase II series of tests, larger plates were used and tested until fracture. The plate sizes ranged from 4 ft square pieces to 6 ft square sections with thicknesses from 1/4 inches to 3/4 inches. This phase investigated the cooling rates on larger plates and the effect of different notch geometries (stress concentrations used to initiate brittle fracture). Phase II was divided into two sections, Phase II-A and Phase II-B. Phase II-A used standard A36 steel, while Phase II-B used marine grade steels. In Phase III, the test structures were significantly larger, in the range of 12 ft by 12 ft by 3 ft high. These structures were designed with more complex geometries to include features similar to those on LNG vessels. The final test phase, Phase IV, investigated differences in the heat transfer (cooling rates) between LNG and LN{sub 2}. All of the tests conducted in this study are used in subsequent parts of the LNG Cascading Damage Study, specifically the computational analyses.

Petti, Jason P.; Kalan, Robert J.

2011-12-01

125

Feasibility of Methods and Systems for Reducng LNG Tanker Fire Hazards.  

National Technical Information Service (NTIS)

In this program concepts for reducing fire hazards that may result from LNG tanker collisions are identified and their technical feasibility evaluated. Concepts considered include modifications to the shipborne LNG containers so that in the event of a con...

1980-01-01

126

33 CFR 165.751 - Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia.  

Code of Federal Regulations, 2010 CFR

...Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia. 165...Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia. (a...the right descending bank of the Savannah River. All marine traffic is...

2010-07-01

127

33 CFR 165.751 - Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia.  

Code of Federal Regulations, 2013 CFR

...Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia. 165...Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia. (a...the right descending bank of the Savannah River. All marine traffic is...

2013-07-01

128

33 CFR 165.751 - Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia.  

Code of Federal Regulations, 2010 CFR

...Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia. 165...Security Zone: LNG mooring slip, Savannah River, Savannah, Georgia. (a...the right descending bank of the Savannah River. All marine traffic is...

2009-07-01

129

Insulating polymer concrete for LNG impounding dikes. [Polymer concretes  

SciTech Connect

An insulating polymer concrete (IPC) composite has been developed under contract to the Gas Research Institute for possible use as a dike insulation material at Liquid Natural Gas (LNG) storage facilities. In the advent of an LNG spill into the impounding dike area, the boiloff rate of the LNG can be substantially reduced if the surfaces of the dike are insulated. This increased safety at the LNG facility will tend to reduce the hazardous explosive mixture with atmospheric air in the surrounding region. The dike insulation material must have a low thermal conductivity and be unaffected by environmental conditions. The IPC composites developed consist of perlite or glass nodule aggregates bound together as a closed cell structure with a polyester resin. In addition to low thermal conductivity and porosity, these composites have correspondingly high strengths and, therefore, can carry transient loads of workmen and maintenance equipment. Prefabricated IPC panels have been installed experimentally and at least one utility is currently considering a complete installation at its LNG facility. 5 refs., 5 tabs.

Fontana, J.J.; Steinberg, M.

1986-03-01

130

Pilot study on the underground lined rock cavern for LNG storage  

Microsoft Academic Search

This paper reports the background information and the initial results obtained from the pilot underground LNG (liquefied natural gas) storage cavern in Korea, where all natural gas is stored in the condition of liquid phase. Many attempts have been made in the past to store LNG underground in unlined containment, though without success. A new concept for storing LNG in

Eui-Seob Park; Yong-Bok Jung; Won-Kyong Song; Dae-Hyuk Lee; So-Keul Chung

2010-01-01

131

Unusual Fire Hazard of LNG Tanker Spills  

Microsoft Academic Search

The spreading and evaporation rates of liquified natural gas spilled on water are estimated theoretically. Subsequent gravitational spread and heating of the vapor evolved from the spill generates a pancake-shaped cloud in 15 minutes or less. Downwind drift of this ground-level cloud to land areas could result in its ignition and complete combustion.

JAMES A. FAY

1973-01-01

132

Monitoring, safety systems for LNG and LPG operators  

SciTech Connect

Operators in Korea and Australia have chosen monitoring and control systems in recent contracts for LNG and LPG storage. Korea Gas Corp. (Kogas) has hired Whessoe Varec, Calais, to provide monitoring systems for four LNG storage tanks being built at Kogas` Inchon terminal. For Elgas Ltd., Port Botany, Australia, Whessoe Varec has already shipped a safety valve-shutdown system to a new LPG cavern-storage facility under construction. The paper describes the systems, terminal monitoring, dynamic approach to tank management, and meeting the growing demand for LPG.

True, W.R.

1998-11-16

133

Comparison of CNG and LNG technologies for transportation applications  

SciTech Connect

This report provides a head-to-head comparison of compressed natural gas (CNG) and liquefied natural gas (LNG) supplied to heavy-duty vehicles. The comparison includes an assessment of the overall efficiency of the fuel delivery system, the cost of the fuel supply system, the efficiency of use in heavy-duty vehicles, and the environmental impact of each technology. The report concludes that there are applications in which CNG will have the advantage, and applications in which LNG will be preferred.

Sinor, J.E. (Sinor (J.E.) Consultants, Inc., Niwot, CO (United States))

1992-01-01

134

Analysis of LNG peakshaving-facility release-prevention systems  

SciTech Connect

The purpose of this study is to provide an analysis of release prevention systems for a reference LNG peakshaving facility. An overview assessment of the reference peakshaving facility, which preceeded this effort, identified 14 release scenarios which are typical of the potential hazards involved in the operation of LNG peakshaving facilities. These scenarios formed the basis for this more detailed study. Failure modes and effects analysis and fault tree analysis were used to estimate the expected frequency of each release scenario for the reference peakshaving facility. In addition, the effectiveness of release prevention, release detection, and release control systems were evaluated.

Pelto, P.J.; Baker, E.G.; Powers, T.B.; Schreiber, A.M.; Hobbs, J.M.; Daling, P.M.

1982-05-01

135

Landfill Gas Conversion to LNG and LCO{sub 2}. Final Report  

SciTech Connect

This report summarizes work on the development of a process to produce LNG (liquefied methane) for heavy vehicle use from landfill gas (LFG) using Acrion's CO{sub 2} wash process for contaminant removal and CO{sub 2} recovery. Work was done in the following areas: (1) production of natural gas pipeline methane for liquefaction at an existing LNG facility, (2) production of LNG from sewage digester gas, (3) the use of mixed refrigerants for process cooling in the production of LNG, liquid CO{sub 2} and pipeline methane, (4) cost estimates for an LNG production facility at the Arden Landfill in Washington PA.

Brown, W.R.; Cook, W. J.; Siwajek, L.A.

2000-10-20

136

LNG cascading damage study. Volume I, fracture testing report  

Microsoft Academic Search

As part of the liquefied natural gas (LNG) Cascading Damage Study, a series of structural tests were conducted to investigate the thermal induced fracture of steel plate structures. The thermal stresses were achieved by applying liquid nitrogen (LNâ) onto sections of each steel plate. In addition to inducing large thermal stresses, the lowering of the steel temperature simultaneously reduced the

Jason P. Petti; Robert J. Kalan

2011-01-01

137

The role of consequence modeling in LNG facility siting  

Microsoft Academic Search

Liquefied natural gas (LNG) project modeling focuses on two primary issues, facility siting and the physical layout of element spacing. Modeling often begins with an analysis of these issues, while ensuring code compliance and sound engineering practice. The most commonly performed analysis involves verifying compliance with the siting provisions of NFPA 59A, which primarily concern property-line spacing (offsite hazard impacts).

Dennis W. Taylor

2007-01-01

138

Comparison of hypothetical LNG and fuel oil fires on water  

Microsoft Academic Search

Large spills of refined petroleum products have been an occasional occurrence over the past few decades. This has not been true for large spills of liquefied natural gas (LNG). This paper compares the likely similarities and differences between accidental releases from a ship of sizable quantities of these different hydrocarbon fuels, their subsequent spreading, and possible pool-fire behavior. Quantitative estimates

William Lehr; Debra Simecek-Beatty

2004-01-01

139

LNG Safety Research: FEM3A Model Development  

SciTech Connect

This quarterly report for DE-FG26-04NT42030 covers a period from July 1, 2004 to September 30, 2004. Activity during this period included preparation of a CD containing the FEM3a FORTRAN code for distribution and organization of an LNG safety workshop. Contract negotiation between GTI and University of Arkansas continued.

Iraj A. Salehi

2004-09-30

140

LNGFIRE: A Thermal Radiation Model for LNG Fires (for Microcomputers).  

National Technical Information Service (NTIS)

Results of Liquified Natural Gas (LNG) fire tests conducted since 1962 were reviewed and an improved model for predicting exclusion distances was developed and verified. The model assumes that the flame takes the shape of a cylinder or a parallelepiped, d...

1990-01-01

141

Vapor Detector.  

National Technical Information Service (NTIS)

It has been shown that coated piezoelectric crystals can detect quantitatively vapors of unsymmetrical dimethyl hydrazine (UDMH) in the presence of a background level of humidity which might be encountered by a GI in the field. The UDMH levels detected ra...

G. M. Varga

1974-01-01

142

Vapor Detection  

NASA Astrophysics Data System (ADS)

This presentation will describe recent results in exploiting the vapor detection technology developed at Caltech that forms the basis for a low power, simple "electronic nose". Thin films of carbon black-organic polymer composites have been deposited across two metallic leads, with swelling-induced resistance changes of the films signaling the presence of vapors. To identify and classify vapors, arrays of such vapor sensing elements have been constructed. Each element contained a different organic polymer as the insulating phase. The differing gas-solid partition coefficients for the various polymers of the detector array produced a pattern of resistance changes that was used to classify vapors and vapor mixtures. The performance of this system towards DNT, the predominant signature in the vapor phase above land mines, has been evaluated in detail, with robust detection demonstrated in the laboratory in less than 5 s in air at DNT levels in the low ppb range. We will also discuss integration of the sensors, signal preprocessing, signal processing, and data analysis functions into a single, low power, low cost, "nose chip". In addition, we report advances in fluidic design that allow improvements in signal/noise through optimization of the detector film area and geometric optimization of the detector film volume as it interacts with the injected flow from the sampling analyte plug. An analytical expression derived for the signal/noise performance as a function of detector area implies that there is an optimum detector film volume which will produce the best signal/noise ratio for a given carbon black-polymer composite when exposed to a finite volume of sampled analyte. This prediction has been verified experimentally by exploring the response behavior of detectors having a variety of different geometric form factors. We also demonstrate that useful information can be obtained from the spatiotemporal response profile of an analyte moving at a controlled flow velocity across an array of chemically identical, but spatially nonequivalent, detector films. W also demonstrate the use of these design principles, incorporated with an analysis of the changes in detector signals in response to variations in analyte flow rate, to obtain useful information on the composition of analytes and analyte mixtures.

Lewis, Nathan

2003-04-01

143

Investigation of propulsion system for large LNG ships  

NASA Astrophysics Data System (ADS)

Requirements to move away from coal for power generation has made LNG as the most sought after fuel source, raising steep demands on its supply and production. Added to this scenario is the gradual depletion of the offshore oil and gas fields which is pushing future explorations and production activities far away into the hostile environment of deep sea. Production of gas in such environment has great technical and commercial impacts on gas business. For instance, laying gas pipes from deep sea to distant receiving terminals will be technically and economically challenging. Alternative to laying gas pipes will require installing re-liquefaction unit on board FPSOs to convert gas into liquid for transportation by sea. But, then because of increased distance between gas source and receiving terminals the current medium size LNG ships will no longer remain economical to operate. Recognizing this business scenario shipowners are making huge investments in the acquisition of large LNG ships. As power need of large LNG ships is very different from the current small ones, a variety of propulsion derivatives such as UST, DFDE, 2-Stroke DRL and Combined cycle GT have been proposed by leading engine manufacturers. Since, propulsion system constitutes major element of the ship's capital and life cycle cost, which of these options is most suited for large LNG ships is currently a major concern of the shipping industry and must be thoroughly assessed. In this paper the authors investigate relative merits of these propulsion options against the benchmark performance criteria of BOG disposal, fuel consumption, gas emissions, plant availability and overall life cycle cost.

Sinha, R. P.; Nik, Wan Mohd Norsani Wan

2012-09-01

144

Oil dispersants  

Microsoft Academic Search

This book contains papers presented at a symposium of the American Society for Testing and Materials. The topics covered include: The effect of elastomers on the efficiency of oil spill dispersants; planning for dispersant use; field experience with dispersants for oil spills on land; and measurements on natural dispersion.

Flaherty

1989-01-01

145

40 CFR Table W - 5 of Subpart W of Part 98-Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage  

Code of Federal Regulations, 2013 CFR

...Methane Emission Factors for Liquefied Natural Gas (LNG) Storage W Table W...GREENHOUSE GAS REPORTING Petroleum and Natural Gas Systems Definitions. Pt...Methane Emission Factors for Liquefied Natural Gas (LNG) Storage LNG...

2013-07-01

146

Qualitative Risk Assessment for an LNG Refueling Station and Review of Relevant Safety Issues  

SciTech Connect

This report is a qualitative assessment of the public and worker risk involved with the operation of a liquefied natural gas (LNG) vehicle refueling facility. This study includes facility maintenance and operations, tank truck deliveries, and end-use vehicle fueling; it does not treat the risks of LNG vehicles on roadways. Accident initiating events are identified by using a Master Logic Diagram, a Failure Modes and Effects Analysis, and historical operating experiences. The event trees were drawn to depict possible sequences of mitigating events following the initiating events. The phenomenology of LNG and other vehicle fuels is discussed to characterize the hazard posed by LNG usage. Based on the risk modeling and analysis, recommendations are given to improve the safety of LNG refueling stations in the areas of procedures and training, station design, and the dissemination of ``best practice`` information throughout the LNG community.

Siu, N.; Herring, J.S.; Cadwallader, L.; Reece, W.; Byers, J.

1998-02-01

147

Interim qualitative risk assessment for an LNG refueling station and review of relevant safety issues  

SciTech Connect

This report is a qualitative assessment of the public and worker risk involved with the operation of a liquefied natural (LNG) vehicle refueling facility. This study includes facility maintenance and operations, tanker truck delivers and end-use vehicle fueling; it does not treat the risks of LNG vehicles on roadways. Accident initiating events are identified by using a Master Logic Diagram, a Failure Modes and Effects analysis and historical operating experiences. The event trees were drawn to depict possible sequences of mitigating events following the initiating events. The phenomenology of LNG and other vehicle fuels is discussed to characterize the hazard posed by LNG usage. Based on the risk modeling and analysis, recommendations are given to improve the safety of LNG refueling stations in the areas of procedures and training, station design, and the dissemination of best practice information throughout the LNG community.

Siu, N.; Herring, S.; Cadwallader, L.; Reece, W.; Byers, J.

1997-07-01

148

Flare system for safe disposal of LNG from a disabled tanker  

SciTech Connect

The feasibility of a flare system for the rapid and safe incineration of the cargo of a disabled LNG tanker is evaluated. The project developed design parameters and proof-of-principle investigations of a system for off-loading and flaring LNG from a disabled LNG tanker. The system described offers enough promise to warrant additional investigation, if cargo burning is desired as a way of reducing other possible hazards.

Not Available

1982-12-01

149

Vapor Bubble Nucleation: A Microscopic Phenomenon  

Microsoft Academic Search

In this article, vapor bubble nucleation in liquid and the evaporation process of a liquid droplet at its superheat limit\\u000a were discussed from the viewpoint of molecular clustering (molecular cluster model for bubble nucleation). For the vapor bubble\\u000a formation, the energy barrier against bubble nucleation was estimated by the molecular interaction due to the London dispersion\\u000a force. Bubble nucleation by

Ho-Young Kwak

2004-01-01

150

US North Slope gas and Asian LNG markets  

USGS Publications Warehouse

Prospects for export of liquified natural gas (LNG) from Alaska's North Slope are assessed. Projected market conditions to 2010 show that new LNG capacity beyond announced expansions will be needed to meet regional demand and that supplies will probably come from outside the region. The estimated delivered costs of likely suppliers show that Alaska North Slope gas will not be competitive. The alternative North Slope gas development strategies of transport and sale to the lower 48 states and use on the North Slope for either enhanced oil recovery or conversion to liquids are examined. The alternative options require delaying development until US gas prices increase, exhaustion of certain North Slope oil fields, or advances occur in gas to liquid fuels conversion technology. ?? 1995.

Attanasi, E. D.

1994-01-01

151

The role of consequence modeling in LNG facility siting.  

PubMed

Liquefied natural gas (LNG) project modeling focuses on two primary issues, facility siting and the physical layout of element spacing. Modeling often begins with an analysis of these issues, while ensuring code compliance and sound engineering practice. The most commonly performed analysis involves verifying compliance with the siting provisions of NFPA 59A, which primarily concern property-line spacing (offsite hazard impacts). If the facility is located in the US, compliance with 49 CFR 193 is also required. Other consequence modeling is often performed to determine the spacing of elements within the facility (onsite hazard impacts). Often, many issues concerning in-plant spacing are addressed with the guidance provided in Europe's LNG standard, EN-1473. Spacing of plant buildings in relation to process areas is also a concern as analyzed using the approach given in API RP 752. Studies may also include probabilistic analysis, depending on the perceived risk and cost of mitigation. PMID:16934395

Taylor, Dennis W

2006-08-23

152

Radiation scanning aids tower diagnosis at Arun LNG plant  

SciTech Connect

Radiation scanning has been used effectively to troubleshoot the treating towers of the Arun LNG plant in Sumatra, Indonesia. The plant is one of the world's largest such facilities. The analysis was part of an investigation aimed at increasing the capacity of the treater section of the plant. Radiation scanning is a tool which, in addition to tower differential pressure and product purity, can aid in diagnosing tower performance.

Naklie, M.M. (Mobil Exploration and Producing Services Inc., Dallas, TX (US)); Pless, L. (Tru-Tec Inc., Houston, TX (US)); Gurning, T.P.; Hyasak, M. (P.T. Arun Natural Gas Liquefaction Co., Sumatera (USA))

1990-03-26

153

Comparison of CNG and LNG technologies for transportation applications  

Microsoft Academic Search

This report provides a head-to-head comparison of compressed natural gas (CNG) and liquefied natural gas (LNG) supplied to heavy-duty vehicles. The comparison includes an assessment of the overall efficiency of the fuel delivery system, the cost of the fuel supply system, the efficiency of use in heavy-duty vehicles, and the environmental impact of each technology. The report concludes that there

Sinor

1992-01-01

154

Natural Gas Liquefaction Process for Small-scale LNG Project  

Microsoft Academic Search

In the field of natural gas liquefaction, the small-scale natural gas liquefier has been attracting more and more attentions home and abroad, thanks to its small volume, mobile transportation, easy start-up and shut-down, as well as skid-mounted package. A study was made to choose the optimum liquefaction process to improve the economy of small-scale liquefied natural gas (LNG) plant. The

Cao Wensheng

2012-01-01

155

Transportation Planning and Inventory Management in the LNG Supply Chain  

Microsoft Academic Search

\\u000a In this chapter, the LNG supply chain is introduced, and two planning problems related to the transportation planning and\\u000a inventory management within the chain are presented. The two problems have different characteristics and reflect the planning\\u000a situations for a producer and a vertically integrated company, respectively. Both problems are formulated as mixed integer\\u000a programs, and possible solution methods are briefly

Henrik Andersson; Marielle Christiansen; Kjetil Fagerholt

156

Solar vapor generation enabled by nanoparticles.  

PubMed

Solar illumination of broadly absorbing metal or carbon nanoparticles dispersed in a liquid produces vapor without the requirement of heating the fluid volume. When particles are dispersed in water at ambient temperature, energy is directed primarily to vaporization of water into steam, with a much smaller fraction resulting in heating of the fluid. Sunlight-illuminated particles can also drive H(2)O-ethanol distillation, yielding fractions significantly richer in ethanol content than simple thermal distillation. These phenomena can also enable important compact solar applications such as sterilization of waste and surgical instruments in resource-poor locations. PMID:23157159

Neumann, Oara; Urban, Alexander S; Day, Jared; Lal, Surbhi; Nordlander, Peter; Halas, Naomi J

2012-11-28

157

LNG (liquefied natural gas) in the Asia-Pacific region: Twenty years of trade and outlook for the future  

SciTech Connect

This report discusses the following topics: the current status of LNG trade in the Asia-Pacific region; present structure and projected demand in the Asia-Pacific region; prospective and tentative projects; and LNG contracts: stability versus flexibility.

Kiani, B.

1990-01-01

158

Heavy gas releases: recent dispersion research  

SciTech Connect

The important liquefied fuels which form heavy gases are liquefied natural gas (LNG) (comprised chiefly of methane, but with small amounts of propane and ethane), and liquefied petroleum gas (LPG), (comprised of propane and butane in various ratios). In addition to other fuels with these properties, there are a variety of industrial gases transported in pressurized vessels, such as hydrocarbons (ethylene, propylene, and methyl chloride), and common inorganic gases (ammonia, chlorine, sulfur dioxide, and hydrogen sulfide). Key research work in Europe and the United States is reviewed and the problems of predicting atmospheric dispersion of heavy gas releases are discussed. Some available dispersion models are mentioned, and some results of initial comparisons between models and with field data are given.

Shinn, J.H.; Ermak, D.L.; Koopman, R.P.

1981-11-01

159

In-situ strain monitoring in liquid containers of LNG transporting carriers  

Microsoft Academic Search

Liquefied natural gas (LNG) transport carriers are exposed to a risk by the repeated bump in the LNG container during the vessel traveling over the wave in ocean. The liquid inside the container, especially when it was not fully contained, make a strong bump onto the insulation panel of the tank wall. The insulation panel consists of several layers of

Min-Cheol Oh; Jun-Kyu Seo; Kyung-Jo Kim; Sang-Min Lee; Myung-Hyun Kim

2008-01-01

160

Intermountain Gas expands LNG storage to meet an exaggerated peak load problem  

Microsoft Academic Search

Intermountain Gas Co., Boise, Idaho, uses LNG to solve its excessive winter peak load caused by a seasonal industrial demand and a heavy heating requirement. Having a year-round contract demand of 163 million SCF\\/day from Northwest Pipeline Col., Intermountain Gas must store excess gas as LNG in summer and draw from 3 storage systems for the winter peakshaving days: the

Forsyth

1975-01-01

161

LNGFIRE: A thermal radiation model for LNG fires. Topical report, June 29, 1990. Documentation  

Microsoft Academic Search

The Federal Code Model for predicting exclusion distances from LNG fires (49 CFR 193.2057) was critically evaluated. The results of LNG fire tests carried out to date were reviewed and an improved model for predicting exclusion distances was developed and verified. This model assumes that the flame takes the shape of a cylinder or a parallellepiped, depending on whether the

S. Atallah; J. N. Shah

1990-01-01

162

Comparison of LNG, CNG, and diesel transit bus economics. Topical report, July 1992September 1993  

Microsoft Academic Search

The purpose of the report is to compare the expected costs of operating a transit bus fleet on liquefied natural gas (LNG), compressed natural gas (CNG), and diesel fuel. The special report is being published prior to the overall project final report in response to the current high level of interest in LNG transit buses. It focuses exclusively on the

C. A. Powars; C. B. Moyer; D. R. Luscher; D. D. Lowell; C. J. Pera

1993-01-01

163

78 FR 23552 - Dominion Cove Point LNG, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013

...Cove Point LNG, LP (Dominion Cove Point), 120 Tredegar Street...authorization to construct, modify, own and operate certain facilities to...for the export at its existing Cove Point LNG terminal in Calvert...section 7 of the NGA, Dominion Cove Point seeks authority to...

2013-04-19

164

76 FR 40723 - Dominion Cove Point LNG, LP; Notice of Technical Conference  

Federal Register 2010, 2011, 2012, 2013

...RP11-2136-000; RP11-2137-000] Dominion Cove Point LNG, LP; Notice of Technical...Natural Gas Act (NGA), Dominion Cove Point LNG, LP (Cove Point) filed revised tariff records in Docket Nos. RP11-2136-000 and RP11-2137-000, proposing...

2011-07-11

165

A combined power cycle using refuse incineration and LNG cold energy  

Microsoft Academic Search

The objectives of this paper are to develop a combined power generation cycle using refuse incineration and LNG cold energy, and to conduct parametric analysis to investigate the effects of key parameters on the thermal and exergy efficiencies. The combined cycle consists of an ammonia–water Rankine cycle with refuse incinerator and a LNG cold energy cycle. The combined cycle is

T Miyazaki; Y. T Kang; A Akisawa; T Kashiwagi

2000-01-01

166

Coupled hydro-thermal modeling of ice ring formation around a pilot LNG cavern in rock  

Microsoft Academic Search

A new method of storing LNG (Liquefied Natural Gas) in a lined, hard rock cavern has been developed and verified by the construction and operation of a pilot plant in Korea. Creation of an ice ring is one of the core techniques in LNG storage in a lined rock cavern. The ice ring serves not only as a primary barrier

Yong-Bok Jung; Eui-Seob Park; So-Keul Chung; Ho-Yeoung Kim

2011-01-01

167

Dispersion Basics  

NSDL National Science Digital Library

In this Webcast, Dr. Timothy Spangler (Director of the COMET Program and a former air quality consultant) provides a brief overview of the basics of atmospheric dispersion and how dispersion is modeled, particularly for accidental releases of hazardous materials. The lecture is presented in six sections and covers the effects of stability, turbulence, plume rise, and wind. Basic dispersion models are discussed, along with a brief summary of models used in special situations and factors that complicate their use.

Spangler, Tim

2002-11-01

168

Vapor Pressure and Solvent Vapor Hazards  

Microsoft Academic Search

This paper discusses applications of vapor pressure to industrial hygiene. Vapor pressure is the quantitative term characterizing solvent volatility; it is also equivalent to the concentration of solvent vapor at the liquid surface. The ratio between this concentration at the source and the acceptable concentration at the breathing zone is an intrinsic property of each chemical but varies over 6

WILLIAM POPENDORF

1984-01-01

169

Thermodynamic Processes Involving Liquefied Natural Gas at the LNG Receiving Terminals / Procesy termodynamiczne z wykorzystaniem skroplonego gazu ziemnego w terminalach odbiorczych LNG  

NASA Astrophysics Data System (ADS)

The increase in demand for natural gas in the world, cause that the production of liquefied natural gas (LNG) and in consequences its regasification becoming more common process related to its transportation. Liquefied gas is transported in the tanks at a temperature of about 111K at atmospheric pressure. The process required to convert LNG from a liquid to a gas phase for further pipeline transport, allows the use of exergy of LNG to various applications, including for electricity generation. Exergy analysis is a well known technique for analyzing irreversible losses in a separate process. It allows to specify the distribution, the source and size of the irreversible losses in energy systems, and thus provide guidelines for energy efficiency. Because both the LNG regasification and liquefaction of natural gas are energy intensive, exergy analysis process is essential for designing highly efficient cryogenic installations. Wzrost zapotrzebowania na gaz ziemny na ?wiecie powoduje, ?e produkcja skroplonego gazu ziemnego (LNG), a w konsekwencji jego regazyfikacja, staje si? coraz bardziej powszechnym procesem zwi?zanym z jego transportem. Skroplony gaz transportowany jest w zbiornikach w temperaturze oko?o 111K pod ci?nieniem atmosferycznym. Przebieg procesu regazyfikacji niezb?dny do zamiany LNG z fazy ciek?ej w gazow? dla dalszego transportu w sieci, umo?liwia wykorzystanie egzergii LNG do ró?nych zastosowa?, mi?dzy innymi do produkcji energii elektrycznej. Analiza egzergii jest znan? technik? analizowania nieodwracalnych strat w wydzielonym procesie. Pozwala na okre?lenie dystrybucji, ?ród?a i wielko?ci nieodwracalnych strat w systemach energetycznych, a wi?c ustali? wytyczne dotycz?ce efektywnego zu?ycia energii. Poniewa? zarówno regazyfikacja LNG jak i skraplanie gazu ziemnego s? energoch?onne, proces analizy egzergii jest niezb?dny do projektowania wysoce wydajnych instalacji kriogenicznych.

?aciak, Mariusz

2013-06-01

170

Liquefied Noble Gas (LNG) detectors for detection of nuclear materials  

NASA Astrophysics Data System (ADS)

Liquefied-noble-gas (LNG) detectors offer, in principle, very good energy resolution for both neutrons and gamma rays, fast response time (hence high-count-rate capabilities), excellent discrimination between neutrons and gamma rays, and scalability to large volumes. They do, however, need cryogenics. LNG detectors in sizes of interest for fissionable material detection in cargo are reaching a certain level of maturity because of the ongoing extensive R&}D effort in high-energy physics regarding their use in the search for dark matter and neutrinoless double beta decay. The unique properties of LNG detectors, especially those using Liquid Argon (LAr) and Liquid Xenon (LXe), call for a study to determine their suitability for Non-Intrusive Inspection (NII) for Special Nuclear Materials (SNM) and possibly for other threats in cargo. Rapiscan Systems Laboratory, Yale University Physics Department, and Adelphi Technology are collaborating in the investigation of the suitability of LAr as a scintillation material for large size inspection systems for air and maritime containers and trucks. This program studies their suitability for NII, determines their potential uses, determines what improvements in performance they offer and recommends changes to their design to further enhance their suitability. An existing 3.1 liter LAr detector (microCLEAN) at Yale University, developed for R&}D on the detection of weakly interacting massive particles (WIMPs) was employed for testing. A larger version of this detector (15 liters), more suitable for the detection of higher energy gamma rays and neutrons is being built for experimental evaluation. Results of measurements and simulations of gamma ray and neutron detection in microCLEAN and a larger detector (326 liter CL38) are presented.

Nikkel, J. A.; Gozani, T.; Brown, C.; Kwong, J.; McKinsey, D. N.; Shin, Y.; Kane, S.; Gary, C.; Firestone, M.

2012-03-01

171

LNG projects make progress in Oman and Yemen  

SciTech Connect

Two LNG projects in the Middle East, one in Oman and the other in Yemen, are due on stream at the turn of the century--each the largest single project ever put together in its country. Officials described their projects at a yearend 1996 conference in Paris by Institut Francais du Petrole and Petrostrategies. The Oman project develops gas reserves, does gas processing, and transports the gas 360 km to a liquefaction plant to be built on the coast. The Yemen project involves a liquefaction plant and an export terminal.

NONE

1997-02-24

172

Thermal Non-Equilibrium in Dispersed Flow Film Boiling in a Vertical Tube.  

National Technical Information Service (NTIS)

The departure from thermal equilibrium between a dispersed liquid phase and its vapor at high quality during film boiling is investigated. The departure from equilibrium is manifested by the high resistance to heat transfer between the dispersed and conti...

R. P. Forslund W. M. Rohsenow

1966-01-01

173

Advanced Vapor Supply Manifold.  

National Technical Information Service (NTIS)

A four-port vapor supply valve to control a vapor or fluid supply to a vapor growth manifold that eliminates supply source contamination from back diffusion into the supply vapor container is disclosed. This valve greatly improves the ability to sharply a...

I. O. Clark W. J. Debnam A. L. Fripp R. K. Crouch

1985-01-01

174

Potassium vapor topping cycle  

Microsoft Academic Search

The potassium vapor topping cycle is a concept for increasing the efficiency of the Rankine vapor cycle by raising the peak temperature by employing a potassium vapor cycle with a turbine inlet temperature of 1500 to 1600 F (815 to 870 C) in which the waste heat rejected from the condensing potassium vapor is transferred to boiling water and steam

R. S. Holcomb

1978-01-01

175

A NOVEL PROCESS TO USE SALT CAVERNS TO RECEIVE SHIP BORNE LNG  

SciTech Connect

This cooperative research project validates use of man made salt caverns to receive and store the cargoes of LNG ships in lieu of large liquid LNG tanks. Salt caverns will not tolerate direct injection of LNG because it is a cryogenic liquid, too cold for contact with salt. This research confirmed the technical processes and the economic benefits of pressuring the LNG up to dense phase, warming it to salt compatible temperatures and then directly injecting the dense phase gas into salt caverns for storage. The use of salt caverns to store natural gas sourced from LNG imports, particularly when located offshore, provides a highly secure, large scale and lower cost import facility as an alternative to tank based LNG import terminals. This design can unload a ship in the same time as unloading at a tank based terminal. The Strategic Petroleum Reserve uses man made salt caverns to securely store large quantities of crude oil. Similarly, this project describes a novel application of salt cavern gas storage technologies used for the first time in conjunction with LNG receiving. The energy industry uses man made salt caverns to store an array of gases and liquids but has never used man made salt caverns directly in the importation of LNG. This project has adapted and expanded the field of salt cavern storage technology and combined it with novel equipment and processes to accommodate LNG importation. The salt cavern based LNG receiving terminal described in the project can be located onshore or offshore, but the focus of the design and cost estimates has been on an offshore location, away from congested channels and ports. The salt cavern based terminal can provide large volumes of gas storage, high deliverability from storage, and is simplified in operation compared to tank based LNG terminals. Phase I of this project included mathematical modeling that proved a salt cavern based receiving terminal could be built at lower capital cost, and would have significantly higher delivery capacity, shorter construction time, and be much more secure than a conventional liquid tank based terminal. Operating costs of a salt cavern terminal are lower than tank based terminals because ''boil off'' is eliminated and maintenance costs of caverns are lower than LNG tanks. Phase II included the development of offshore mooring designs, wave tank tests, high pressure LNG pump field tests, heat exchanger field tests, and development of a model offshore LNG facility and cavern design. Engineers designed a model facility, prepared equipment lists, and confirmed capital and operating costs. In addition, vendors quoted fabrication and installation costs, confirming that an offshore salt cavern based LNG terminal would have lower capital and operating costs than a similarly sized offshore tank based terminal. Salt cavern storage is infinitely more secure than surface storage tanks, far less susceptible to accidents or purposeful damage, and much more acceptable to the community. More than thirty industry participants provided cost sharing, technical expertise, and guidance in the conduct and evaluation of the field tests, facility design and operating and cost estimates. Their close participation has accelerated the industry's acceptance of the conclusions of this research. The industry participants also developed and submitted several alternative designs for offshore mooring and for high pressure LNG heat exchangers in addition to those that were field tested in this project. HNG Storage, a developer, owner, and operator of natural gas storage facilities, and a participant in the DOE research has announced they will lead the development of the first offshore salt cavern based LNG import facility. Which will be called the Freedom LNG Terminal. It will be located offshore Louisiana, and is expected to be jointly developed with other members of the research group yet to be named. An offshore port license application is scheduled to be filed by fourth quarter 2005 and the terminal could be operational by 2009. This terminal allows the large volume importa

Michael M. McCall; William M. Bishop; Marcus Krekel; James F. Davis; D. Braxton Scherz

2005-05-31

176

Physical Dispersion.  

National Technical Information Service (NTIS)

The constitutive parameters, which are defined according to the approach presented in the recent report series to the TDFV case, are different for both of definitions and used functions. The authors call the physical dispersion this case. The conversion o...

T. Sengor

2001-01-01

177

Outlook for third Malaysian LNG plant brighter with big gas find  

SciTech Connect

Prospects for a third liquefied natural gas export complex in Malaysia are brighter than ever. A unit of Occidental Petroleum Corp. has drilled its fourth and biggest natural gas strike into a carbonate reef on Block SK-8 off Sarawak, East Malaysia, turning up still more potential reserves for the country's proposed third LNG plant. The find brings to a combined total of 5 tcf of gas in place in the four SK-8 fields for which Oxy has disclosed test results. Well details are given. The LNG project under study would make Malaysia the largest supplier of LNG to the rapidly expanding East Asian market, Oxy said.

Not Available

1993-05-03

178

75 FR 70350 - Liberty Natural Gas LLC, Liberty Liquefied Natural Gas (LNG) Deepwater Port License Application  

Federal Register 2010, 2011, 2012, 2013

...Administration [USCG-2010-0993] Liberty Natural Gas LLC, Liberty Liquefied Natural Gas (LNG) Deepwater Port License Application AGENCY...received an application for the licensing of a natural gas deepwater port and the application...

2010-11-17

179

76 FR 4417 - Liberty Natural Gas LLC, Liberty Liquefied Natural Gas (LNG) Deepwater Port License Application  

Federal Register 2010, 2011, 2012, 2013

...Administration [USCG-2010-0993] Liberty Natural Gas LLC, Liberty Liquefied Natural Gas (LNG) Deepwater Port License Application AGENCY...Application. The application describes an offshore natural gas deepwater port facility that would be...

2011-01-25

180

33 CFR 127.703 - Access to the marine transfer area for LNG.  

Code of Federal Regulations, 2013 CFR

...a) Access to the marine transfer area for LNG from the shoreside...is limited toâ (1) Personnel who work at the waterfront...including persons assigned for transfer operations, vessel personnel, and delivery and...

2013-07-01

181

Refrigeration cycles for future base-load LNG plants need a close look  

Microsoft Academic Search

This paper briefly reviews the liquefaction cycles which are presently used in base-load liquefied natural gas (LNG) plants, and presents some information for equipment and process selection for new facilities. Twelve base-load LNG facilities are described. The facilities are categorized according to the general type of refrigeration cycle used: classical cascade, mixed refrigerant, and propane-precooled\\/mixed-refrigerant. Variations exist within each category,

Geist

1985-01-01

182

Seismic analysis of a LNG storage tank isolated by a multiple friction pendulum system  

Microsoft Academic Search

The seismic response of an isolated vertical, cylindrical, extra-large liquefied natural gas (LNG) tank by a multiple friction\\u000a pendulum system (MFPS) is analyzed. Most of the extra-large LNG tanks have a fundamental frequency which involves a range\\u000a of resonance of most earthquake ground motions. It is an effective way to decrease the response of an isolation system used\\u000a for extra-large

Ruifu Zhang; Dagen Weng; Xiaosong Ren

2011-01-01

183

A study of the gas flow through a LNG safety valve  

Microsoft Academic Search

A safety valve functions to control an upper limit of pressure inside the LNG line of transportation. If the pressure inside\\u000a the safety valve nozzle exceeds a pre-determined value on the valve sheet which plugs the nozzle, an excess of LNG discharges\\u000a through the gap between the nozzle exit and valve sheet. In this situation, the forces acting on the

Heuy-Dong Kim; Jun-Hee Lee; Kyung-Am Park; Toshiaki Setoguchi; Shigeru Matsuo

2006-01-01

184

Explosives Vapor Characterization.  

National Technical Information Service (NTIS)

The vaporous emissions from seventeen explosives were investigated by gas chromatographic and combined gas chromatographic/mass spectrometric techniques using a novel collection device. The vapor emission rates were followed as a function of time untile t...

F. H. Jarke S. M. Gordon

1982-01-01

185

Comparison of LNG, CNG, and diesel transit bus economics. Topical report, July 1992-September 1993  

SciTech Connect

The purpose of the report is to compare the expected costs of operating a transit bus fleet on liquefied natural gas (LNG), compressed natural gas (CNG), and diesel fuel. The special report is being published prior to the overall project final report in response to the current high level of interest in LNG transit buses. It focuses exclusively on the economics of LNG buses as compared with CNG and diesel buses. The reader is referred to the anticipated final report, or to a previously published 'White Paper' report (Reference 1), for information regarding LNG vehicle and refueling system technology and/or the economics of other LNG vehicles. The LNG/CNG/diesel transit bus economics comparison is based on total life-cycle costs considering all applicable capital and operating costs. The costs considered are those normally borne by the transit property, i.e., the entity facing the bus purchase decision. These costs account for the portion normally paid by the U.S. Department of Transportation (DOT) Federal Transit Administration (FTA). Transit property net costs also recognize the sale of emissions reduction credits generated by using natural gas (NG) engines which are certified to levels below standards (particularly for NOX).

Powars, C.A.; Moyer, C.B.; Luscher, D.R.; Lowell, D.D.; Pera, C.J.

1993-10-20

186

Vapor Phase Pyrolysis.  

National Technical Information Service (NTIS)

The vapor phase pyrolysis process is designed exclusively for the lunar production of oxygen. In this concept, granulated raw material (soil) that consists almost entirely of metal oxides is vaporized and the vapor is raised to a temperature where it diss...

W. Steurer

1992-01-01

187

Graphite Dispersion.  

National Technical Information Service (NTIS)

The method relates to a uniform dispersion of oxide ceramic-coated nuclear reactor spheres within a matrix essentially of graphite. The method involves tumbling the spheres, spraying with benzene and a slurry of graphite in a solution of medium coal-tar p...

M. C. Brockway

1965-01-01

188

Evaporating liquid flow in a channel (An integral model based on shallow water flow approximation)  

Microsoft Academic Search

Liquefied Natural Gas (LNG) storage facilities generally include channels to convey potential spills of the liquid to an impoundment. There is increasing concern that dispersion of vapors generated by flow of LNG in a channel may lead to higher than limit vapor concentrations for safety at site boundary from channels that may be close to the dike walls. This issue

Phani K. Raj

2011-01-01

189

Three-dimensional model for simulating atmospheric dispersion of heavy-gases over complex terrain  

SciTech Connect

To help understand heavy gas releases and simulate the resultant dispersion, we have developed a three-dimensional finite element model called FEM3 and an improved version names FEM3A for solving the time dependent conservation equations based on generalized anelastic approximation. Recent enhancements to the model to include the treatment of dispersion scenarios involving density variations much larger than the liquefied natural gas range and an advanced turbulence submodel based on the buoyancy-extended transport equations. This paper presents the main features of the present model FEM3C and numerical results from the simulations of a field-scale LNG spill experiment.

Chan, S.T.

1997-09-01

190

78 FR 53750 - EcoEléctrica, L.P.; Notice of Intent To Prepare an Environmental Assessment for the Proposed LNG...  

Federal Register 2010, 2011, 2012, 2013

...Request for Comments on Environmental Issues The staff of...will prepare an environmental assessment (EA) that will discuss the environmental impacts of the LNG...ctrica) at its liquefied natural gas (LNG) facility...

2013-08-30

191

Optimization and testing of the Beck Engineering free-piston cryogenic pump for LNG systems on heavy vehicles. Final technical report  

SciTech Connect

Task 7 was completed by reaching Milestone 7: Test free piston cryogenic pump (FPCP) in Integrated LNG System. Task 4: Alternative Pump Design was also completed. The type of performance of the prototype LNG system is consistent with requirements of fuel systems for heavy vehicles; however, the maximum flow capacity of the prototype LNG system is significantly less than the total flow requirement. The flow capacity of the prototype LNG system is determined by a cavitation limit for the FPCP.

Beck, Douglas S.

2003-01-10

192

Vapor spill monitoring method  

DOEpatents

Method for continuous sampling of liquified natural gas effluent from a spill pipe, vaporizing the cold liquified natural gas, and feeding the vaporized gas into an infrared detector to measure the gas composition. The apparatus utilizes a probe having an inner channel for receiving samples of liquified natural gas and a surrounding water jacket through which warm water is flowed to flash vaporize the liquified natural gas.

Bianchini, Gregory M. (Livermore, CA); McRae, Thomas G. (Livermore, CA)

1985-01-01

193

Seismic analysis of a LNG storage tank isolated by a multiple friction pendulum system  

NASA Astrophysics Data System (ADS)

The seismic response of an isolated vertical, cylindrical, extra-large liquefied natural gas (LNG) tank by a multiple friction pendulum system (MFPS) is analyzed. Most of the extra-large LNG tanks have a fundamental frequency which involves a range of resonance of most earthquake ground motions. It is an effective way to decrease the response of an isolation system used for extra-large LNG storage tanks under a strong earthquake. However, it is difficult to implement in practice with common isolation bearings due to issues such as low temperature, soft site and other severe environment factors. The extra-large LNG tank isolated by a MFPS is presented in this study to address these problems. A MFPS is appropriate for large displacements induced by earthquakes with long predominant periods. A simplified finite element model by Malhotra and Dunkerley is used to determine the usefulness of the isolation system. Data reported and statistically sorted include pile shear, wave height, impulsive acceleration, convective acceleration and outer tank acceleration. The results show that the isolation system has excellent adaptability for different liquid levels and is very effective in controlling the seismic response of extra-large LNG tanks.

Zhang, Ruifu; Weng, Dagen; Ren, Xiaosong

2011-06-01

194

Flexible LNG supply, storage and price formation in a global natural gas market  

NASA Astrophysics Data System (ADS)

The body of work included in this dissertation explores the interaction of the growing, flexible liquefied natural gas (LNG) trade with the fundamentals of pipeline gas supply, gas storage, and gas consumption. By nature of its uses---largely for residential heating and electric power generation---the consumption of natural gas is highly variable both seasonally and on less predictable daily and weekly timescales. Flexible LNG trade will interconnect previously isolated regional gas markets, each with non-correlated variability in gas demand, differing gas storage costs, and heterogeneous institutional structures. The dissertation employs a series of analytical models to address key issues that will affect the expansion of the LNG trade and the implications for gas prices, investment and energy policy. First, I employ an optimization model to evaluate the fundamentals of seasonal LNG swing between markets with non-correlated gas demand (the U.S. and Europe). The model provides insights about the interaction of LNG trade with gas storage and price formation in interconnected regional markets. I then explore how random (stochastic) variability in gas demand will drive spot cargo movements and covariation in regional gas prices. Finally, I analyze the different institutional structures of the gas markets in the U.S. and Europe and consider how managed gas markets in Europe---without a competitive wholesale gas market---may effectively "export" supply and price volatility to countries with more competitive gas markets, such as the U.S.

Hayes, Mark Hanley

195

Zero-Emission Combined Power Cycle Using LNG Cold  

NASA Astrophysics Data System (ADS)

A potential zero emission combined power generation plant fired by liquefied natural gas (LNG) has been investigated. A mixture of carbon dioxide (CO2)-steam is used as the working fluid of a gas turbine cycle, which replaces the normal combustion-in-air products and air, notably as the thermal ballast for the control of flame temperature. Oxygen (O2) is used as the fuel oxidant and is obtained from an air separation unit (ASU). The excess CO2 due to combustion is extracted by a simple flow separator and liquefied ready to be reused and/or sequestered. The plant configuration and thermodynamics of the cycle are discussed first and then the optimised overall efficiency of the plant is calculated with a comparison of 100% and 120% stoichiometric combustion. The overall net efficiency, optimised to pressure and temperature levels complying with the material and cooling techniques currently available, is around 56% (LHV basis), including the energy penalty of the ASU and the CO2 separation.

Velautham, Sanjayan; Ito, Takehiro; Takata, Yasuyuki

196

How States Can Affect Federal Deepwater Port LNG Licensing Decisions: A Case Study Involving the Deepwater Port Act and the Coastal Zone Management Act  

Microsoft Academic Search

This Article explores the general role of coastal states in permitting offshore LNG terminals, and the specific role that California played in the licensing process for the proposed Cabrillo Port LNG project. There are many facets of state authority, including the approvals required for the portions of LNG projects located within a coastal state’s jurisdiction (primarily within the first three

Linda Krop

2011-01-01

197

Numerical simulation of water injection into vapor-dominated reservoirs  

SciTech Connect

Water injection into vapor-dominated reservoirs is a means of condensate disposal, as well as a reservoir management tool for enhancing energy recovery and reservoir life. We review different approaches to modeling the complex fluid and heat flow processes during injection into vapor-dominated systems. Vapor pressure lowering, grid orientation effects, and physical dispersion of injection plumes from reservoir heterogeneity are important considerations for a realistic modeling of injection effects. An example of detailed three-dimensional modeling of injection experiments at The Geysers is given.

Pruess, K.

1995-01-01

198

Environmental Impact Assessment For Oman LNG Expansion Project: NO 2 Air Quality Analysis with A Proposal For A Third Train  

Microsoft Academic Search

Oman entered the LNG market (liquefied Natural Gas) in April 2000 with the first shipment to South Korea. Oman LNG plant is currently producing 6.6 million metric tonne per annum from two trains. However, there are plans for expansion of the plant to increase its existing capacity by adding one more gas liquefaction train (train 3). The purpose of this

Sabah A. Abdul-Wahab; Krishnasamy Raman; Mazin Al-Riyamy; Mohammed Al-Barashdi

2002-01-01

199

Guidance on risk analysis and safety implications of a large liquefied natural gas (LNG) spill over water  

Microsoft Academic Search

While recognized standards exist for the systematic safety analysis of potential spills or releases from LNG (Liquefied Natural Gas) storage terminals and facilities on land, no equivalent set of standards or guidance exists for the evaluation of the safety or consequences from LNG spills over water. Heightened security awareness and energy surety issues have increased industry's and the public's attention

Gerald William Wellman; Brian Matthew Melof; Anay Josephine Luketa-Hanlin; Marion Michael Hightower; John Morgan Covan; Louis Alan Gritzo; Michael James Irwin; Michael Jiro Kaneshige; Charles W. Morrow

2004-01-01

200

LNGFIRE: A thermal-radiation model for LNG fires. Topical report, October 25, 1988June 29, 1990. documentation  

Microsoft Academic Search

The Federal Code Model for predicting exclusion distances from Liquified Natural Gas (LNG) fires (49 CFR 193.2057) was critically evaluated. The results of LNG fire tests carried out to date were reviewed, and an improved model for predicting exclusion distances was developed and verified. The model assumes that the flame takes the shape of a cylinder or a parallellepiped, depending

S. Atallah; J. N. Shah

1990-01-01

201

The utilization of LH2 and LNG cold for generation of electric power by a cryogenic-type Stirling engine  

Microsoft Academic Search

In a regasification process for LNG and LH2, a cryogenic-type Stirling engine combined with an electric generator is used as the main component. This engine is cooled by LNG or LH2 and is heated by hot water rejected from the power station, so that the engine runs and supplies additional electric power together with fuel gas supplied at room temperature.

K. Oshima; Y. Ishizaki; S. Kamiyama; M. Akiyama; M. Okuda

1978-01-01

202

77 FR 59601 - Dominion Cove Point LNG, LP; Notice of Intent To Prepare an Environmental Assessment for the...  

Federal Register 2010, 2011, 2012, 2013

...Environmental Review, and Notice of Public Scoping...environmental impacts of the Cove Point Liquefaction Project...facilities by Dominion Cove Point LNG, LP (Dominion...capabilities to its existing Cove Point LNG Terminal located on the Chesapeake Bay in Lusby,...

2012-09-28

203

77 FR 66454 - Gulf LNG Liquefaction Company, LLC; Application for Long-Term Authorization To Export Liquefied...  

Federal Register 2010, 2011, 2012, 2013

...the Gulf LNG Terminal to any country (i) with which the United...authorization to export LNG to FTA countries, DOE found that the applicants...environmentally damaging fuels in those countries. Further details can be found...impact on the U.S. economy (GDP), consumers, and...

2012-11-05

204

Particle dispersion in turbulent sprays  

NASA Astrophysics Data System (ADS)

Measurements of droplet dispersion and vaporization rates are carried out and compared with computational predictions. Droplet dispersion, mean axial velocity, and the axial autocorrelation function of the droplets are measured using a laser sheet technique. The experimental facility is modified to accommodate a true spray using an ultrasonic atomizer and droplets injected with a fluorescent dye. The computational part of the project is the development of a Large Eddy Simulation (LES) method for the turbulent jet. A LES-model for the unresolved scales of the flow is implemented into the Navier-Stokes solver. The results for filtered and unfiltered variables are compared to the experiments and improvement of the particle statistics due to the LES-model is found.

Kennedy, Ian M.; Kollmann, Wolfgang

1993-04-01

205

Dispersion, controlled dispersion, and three applications  

Microsoft Academic Search

Causality dictates that all physical media must be dispersive. (We will call a medium dispersive if its refractive index varies with frequency.) Ordinarily, strong dispersion is accompanied either by strong absorption or strong gain. However, over the past 15 years several groups have demonstrated that it is possible to have media that are both strongly dispersive and roughly transparent for

Douglas H. Bradshaw

2010-01-01

206

Applications of human factors engineering to LNG release prevention and control  

SciTech Connect

The results of an investigation of human factors engineering and human reliability applications to LNG release prevention and control are reported. The report includes a discussion of possible human error contributions to previous LNG accidents and incidents, and a discussion of generic HF considerations for peakshaving plants. More specific recommendations for improving HF practices at peakshaving plants are offered based on visits to six facilities. The HF aspects of the recently promulgated DOT regulations are reviewed, and recommendations are made concerning how these regulations can be implemented utilizing standard HF practices. Finally, the integration of HF considerations into overall system safety is illustrated by a presentation of human error probabilities applicable to LNG operations and by an expanded fault tree analysis which explicitly recognizes man-machine interfaces.

Shikiar, R.; Rankin, W.L.; Rideout, T.B.

1982-06-01

207

Constrained Vapor Bubble Experiment  

Microsoft Academic Search

Microgravity experiments on the Constrained Vapor Bubble Heat Exchanger, CVB, are being developed for the International Space Station. In particular, we present results of a precursory experimental and theoretical study of the vertical Constrained Vapor Bubble in the Earth's environment. A novel non-isothermal experimental setup was designed and built to study the transport processes in an ethanol\\/quartz vertical CVB system.

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

2002-01-01

208

Comparison of CNG and LNG technologies for transportation applications. Final subcontract report, June 1991--December 1991  

SciTech Connect

This report provides a head-to-head comparison of compressed natural gas (CNG) and liquefied natural gas (LNG) supplied to heavy-duty vehicles. The comparison includes an assessment of the overall efficiency of the fuel delivery system, the cost of the fuel supply system, the efficiency of use in heavy-duty vehicles, and the environmental impact of each technology. The report concludes that there are applications in which CNG will have the advantage, and applications in which LNG will be preferred.

Sinor, J.E. [Sinor (J.E.) Consultants, Inc., Niwot, CO (United States)

1992-01-01

209

Chemical vapor synthesis of niobium aluminides. Final report, Apr 89-Jul 91  

SciTech Connect

Chemical vapor deposition of niobium aluminides, niobium silicides, metal-rich compositions containing dispersed metallic phases, and ternary compositions in the titanium-niobium aluminum system was performed by several techniques. Process chemistry models were used to select deposition conditions and for correlation with experimental results on deposit compositions. Conditions were identified which permitted direct chemical vapor deposition of small samples of intermetallic foils.

Chin, J.; Norman, J.H.; Reynolds, G.H.

1992-01-01

210

Holographic chemical vapor sensor  

NASA Astrophysics Data System (ADS)

A holographic interferometer senses vapor-induced optical path length changes in polymer or other chemically sensitive films. The interferometer is inherently sensitive to changes in chemical vapor content, self-compensates for drifts, and accommodates a large array of sensor elements. A sniff-locked-loop synchronous detection method takes advantage of the interferometer's rapid response to achieve vapor concentration sensitivity in the parts-per-billion (ppb, parts in 10^9) range. We demonstrate, for example, 40 ppb sensitivity to ethyl alcohol using poly(N-vinyl pyrrolidone) with a measurement time of 5 s.

Ye, Hongke; Nilsen, Oyvind; Bright, Victor M.; Anderson, Dana Z.

2005-06-01

211

Preasymptotic development of vapor and vapor-gas bubbles  

Microsoft Academic Search

Using an optical technique, the existence of the minimum growth rate during the initial stage of the development of vapor and vapor-gas bubbles is established. In this paper models of the development of vapor and the vapor- gas bubbles in the preasymptotic and subcritical stages are suggested.

I. N. Ilyin; V. P. Grivtsov; S. R. Yaundalder

1990-01-01

212

Chemically reactive coatings for passive fire protection in LNG and LPG storage and transporation  

Microsoft Academic Search

According to Van Dyke Associates and TSI Inc., supporting and containing steels used to store and transport LNG and LPG are best protected in case of fire by thermally reactive subliming compounds. When exposed to fire, such compounds undergo an endothermic reaction; thus the substrate material beneath the coating will not heat up beyond the temperature at which this reaction

B. H. Van Dyke; S. T. Kawaller

1979-01-01

213

Comparison of CNG and LNG technologies for transportation applications. Final subcontract report, June 1991--December 1991.  

National Technical Information Service (NTIS)

This report provides a head-to-head comparison of compressed natural gas (CNG) and liquefied natural gas (LNG) supplied to heavy-duty vehicles. The comparison includes an assessment of the overall efficiency of the fuel delivery system, the cost of the fu...

J. E. Sinor

1992-01-01

214

LIQUID NATURAL GAS (LNG): AN ALTERNATIVE FUEL FROM LANDFILL GAS (LFG) AND WASTEWATER DIGESTER GAS  

SciTech Connect

This Research and Development Subcontract sought to find economic, technical and policy links between methane recovery at landfill and wastewater treatment sites in New York and Maryland, and ways to use that methane as an alternative fuel--compressed natural gas (CNG) or liquid natural gas (LNG) -- in centrally fueled Alternative Fueled Vehicles (AFVs).

VANDOR,D.

1999-03-01

215

PREDICTION OF COMPOSITE PROPERTIES AT CRYOGENIC TEMPERATURES FOR LNG HANDLING FACILITIES PRODUCTION  

Microsoft Academic Search

SUMMARY Four SMEs proposers -CTS (I), Fibrover (I), Material (Be), NCE (Fi)- and three RTD performers -Cimteclab (I), PERA (UK), Pisa University (I)- have been working on a CRAFT project concerning the design and production of new LNG storage and transportation facilities. The project started from the choice and formulation of composite materials, properly behaving at cryogenic temperatures, and considers

FEDERICA MANTOVANI; MASSIMILIANO FRANCESCHI

216

Flexible LNG supply, storage and price formation in a global natural gas market  

Microsoft Academic Search

The body of work included in this dissertation explores the interaction of the growing, flexible liquefied natural gas (LNG) trade with the fundamentals of pipeline gas supply, gas storage, and gas consumption. By nature of its uses---largely for residential heating and electric power generation---the consumption of natural gas is highly variable both seasonally and on less predictable daily and weekly

Mark Hanley Hayes

2007-01-01

217

Risk analysis based LNG facility siting standard in NFPA 59A  

Microsoft Academic Search

In the United States, liquefied natural gas (LNG) has the unique distinction of being the only flammable or hazardous material whose storage terminal (siting), handling and terminal operations are regulated by the federal government. Regulations are promulgated by the Pipeline and Hazardous Materials Administration (PHMSA) of the U.S. Department of Transportation (DOT). Storage and handling of all other flammable and

Phani K. Raj; Theodore Lemoff

2009-01-01

218

Numerical Study on Mixing of Sprayed Liquid in an LNG Storage Tank.  

National Technical Information Service (NTIS)

This paper presents a numerical method to simulate the mixing of heavier LNG sprayed on lighter layer. Numerical results for evolutions of flow field and density field are obtained in a rectangular computational domain which includes the vicinity of the l...

H. Uchida T. Arai M. Sugihara M. Nakayama

1992-01-01

219

75 FR 60095 - Sempra LNG Marketing, LLC; Application for Blanket Authorization To Export Liquefied Natural Gas  

Federal Register 2010, 2011, 2012, 2013

...FE-34), Office of Oil and Gas Global Security and Supply, Office of Fossil Energy...purchasing and marketing supplies of LNG...granted Cheniere Marketing, LLC (Cheniere...substantial quantities of natural gas sufficient...supplies, and the benefits described...

2010-09-29

220

THERMOACOUSTIC LIQUEFACTION OF COAL MINE METHANE TO PRODUCE LNG FOR HEAVY VEHICLE APPLICAITONS  

SciTech Connect

This report describes the activity undertaken by the project members under MORGANTOWN ENERGY TECHNOLOGY CENTER (METC) contract No. DE-AC21-95MC32185 to develop a project that will provide a commercial use for Coal Mine Methane (CMM). In particular, the report describes a project to convert CMM into Liquefied Natural Gas (LNG) and to market that LNG to the transportation sector in and around the I-79 corridor near Morgantown, West Virginia. The report discusses the sources of CMM and provides estimates of the extent of the resource specifically dedicated to the project. It discusses the novel refrigeration technology that will be employed to convert the CMM to LNG and the gas conditioning technology that will be used to bring the raw CMM up to cryogenic processing specifications. Summary capital and operating cost estimates are furnished for the project and specific monetary and schedule requirements are identified so the project can be examined in its entirety. The report discusses the immediate market potential for the successful commercial sale of LNG into the nearby market and provides estimates of future market penetration into local, regional and wider markets. Lastly, the report comments on the environmental effects of the project and extrapolates these benefits to future markets. One of the driving forces for the project is the reduction of environmentally harmful greenhouse gases currently escaping unchecked into the atmosphere. This final section analyzes the TASHER technology's potential net environmental benefits both in terms of greenhouse gases and criteria pollutants.

Dr. Kashi Aminian; Dr. Lloyd English; Dr. Douglas Patchen; Dr. Hema Siriwardane; Charles D. Estes; Raymond L. Zahradnik

1999-10-29

221

Evaluation of drainage system around a lined pilot cavern for underground cryogenic LNG storage  

Microsoft Academic Search

A lined pilot cavern for underground cryogenic LNG (liquefied natural gas) storage was constructed in granite in Daejeon, Korea in 2003 and commissioned in 2004. As the hydrostatic pressure of groundwater and thermal stress due to the formation of ice lenses may damage the containment system, rock drainage around the pilot cavern is needed to maintain the stability of the

Sung-Soo Cha; Gwang-Ok Bae; Kang-Kun Lee; Dae-Hyuck Lee; Jean-Luc Bodin

2008-01-01

222

Analysis of rock drainage and cooling experiments for underground cryogenic LNG storage  

Microsoft Academic Search

Hydrogeological monitoring was conducted around a pilot cavern for underground cryogenic LNG (Liquefied Natural Gas) storage. The monitoring was mainly focused on the operation of a drainage and recharge system. After the operation of the drainage system commenced, the drainage rate decreased rapidly in the initial stages and then decreased gradually. Hydrogeological monitoring revealed that the rock drainage system operated

Sung-Soo Cha; Kang-Kun Lee; Gwang-Ok Bae; Dae-Hyuck Lee; Nicolas Gatelier

2007-01-01

223

Stud welding for fixation of cryogenic insulation of membrane tanks in LNG ship building  

Microsoft Academic Search

The support plates including all of the inner hulls such as E grade steel, weld seams and SUS304L were considered to establish the optimal stud welding condition in LNG ship building. The stainless steel plate was especially applied to the bracket on the liquid dome. The polished and etched surfaces of the welded stud and support plate were examined if

Jeong-Soo LEE; Young-Soo RYU; Nam-In KIM; Bong-Joon KIM; Yoo-Kyung KIM; Myung-Hyun KIM

2009-01-01

224

AMTEC vapor-vapor series connected cells  

NASA Astrophysics Data System (ADS)

An alkali metal thermoelectric converter (AMTEC) having a plurality of cells structurally connected in series to form a septum dividing a plenum into two chambers, and electrically connected in series, is provided with porous metal anodes and porous metal cathodes in the cells. The cells may be planar or annular, and in either case a metal alkali vapor at a high temperature is provided to the plenum through one chamber on one side of the wall and returned to a vapor boiler after condensation at a chamber on the other side of the wall in the plenum. If the cells are annular, a heating core may be placed along the axis of the stacked cells. This arrangement of series-connected cells allows efficient generation of power at high voltage and low current.

Underwood, Mark L.; Williams, Robert M.; Ryan, Margaret A.; Jeffries-Nakamura, Barbara; Oconnor, Dennis

1993-01-01

225

AMTEC vapor-vapor series connected cells  

NASA Astrophysics Data System (ADS)

An alkali metal thermoelectric converter (AMTEC) having a plurality of cells structurally connected in series to form a septum dividing a plenum into two chambers, and electrically connected in series, is provided with porous metal anodes and porous metal cathodes in the cells. The cells may be planar or annular, and in either case a metal alkali vapor at a high temperature is provided to the plenum through one chamber on one side of the wall and returned to a vapor boiler after condensation at a chamber on the other side of the wall in the plenum. If the cells are annular, a heating core may be placed along the axis of the stacked cells. This arrangement of series-connected cells allows efficient generation of power at high voltage and low current.

Underwood, Mark L.; Williams, Roger M.; Ryan, Margaret A.; Nakamura, Barbara J.; Oconnor, Dennis E.

1995-08-01

226

Aligning vapor-grown carbon fibers in polydimethylsiloxane using dc electric or magnetic field  

Microsoft Academic Search

A trace amount of vapor-grown carbon fibers (VGCFs), which, as received, had an aggregated lump form, was completely dispersed in polydimethylsiloxane, a nonpolar viscous liquid, at room temperature by mechanical stirring. Using this uniformly dispersed sample as a starting material, a dc electric or magnetic field was applied to induce the formation of an aligned structure. In situ transmission optical

Tatsuhiro Takahashi; Taichi Murayama; Ayumu Higuchi; Hiroshi Awano; Koichiro Yonetake

2006-01-01

227

18 CFR 157.21 - Pre-filing procedures and review process for LNG terminal facilities and other natural gas...  

Code of Federal Regulations, 2010 CFR

...LNG terminal facilities and other natural gas facilities prior to filing of applications...DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES...ABANDONMENT UNDER SECTION 7 OF THE NATURAL GAS ACT Applications for...

2009-04-01

228

18 CFR 157.21 - Pre-filing procedures and review process for LNG terminal facilities and other natural gas...  

Code of Federal Regulations, 2010 CFR

...LNG terminal facilities and other natural gas facilities prior to filing of applications...DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES...ABANDONMENT UNDER SECTION 7 OF THE NATURAL GAS ACT Applications for...

2010-04-01

229

33 CFR 165.1709 - Security Zones: Liquefied Natural Gas Tanker Transits and Operations at Phillips Petroleum LNG...  

Code of Federal Regulations, 2013 CFR

...false Security Zones: Liquefied Natural Gas Tanker Transits and Operations...1709 Security Zones: Liquefied Natural Gas Tanker Transits and Operations...1000-yard radius of the Liquefied Natural Gas (LNG) tankers during their inbound and...

2013-07-01

230

78 FR 62344 - Sabine Pass Liquefaction Expansion, LLC, Sabine Pass Liquefaction, LLC, and Sabine Pass LNG, L.P...  

Federal Register 2010, 2011, 2012, 2013

...application under section 3(a) of the Natural Gas Act (NGA) for authorization to site...and operate additional liquefied natural gas (LNG) export facilities at the Sabine...own, and operate new interstate natural gas pipeline, compression, and related...

2013-10-18

231

Simplified Procedures for Seismic Analysis and Design of Piers and Wharves in Marine Oil and LNG Terminals.  

National Technical Information Service (NTIS)

This investigation developed simplified procedures for the seismic analysis and design of pile supported wharves and piers in Marine Oil and LNG Terminals. A simplified coefficient-based approach is proposed for estimating seismic displacement demand for ...

R. K. Goel

2010-01-01

232

Gasoline vapor recovery  

SciTech Connect

In a gasoline distribution network wherein gasoline is drawn from a gasoline storage tank and pumped into individual vehicles and wherein the gasoline storage tank is refilled periodically from a gasoline tanker truck, a method of recovering liquid gasoline from gasoline vapor that collects in the headspace of the gasoline storage tank as the liquid gasoline is drawn therefrom, said method comprising the steps of: (a) providing a source of inert gas; (b) introducing inert gas into the gasoline storage tank as liquid gasoline is drawn therefrom so that liquid gasoline drawn from the tank is displaced by inert gas and gasoline vapor mixes with the inert gas in the headspace of the tank; (c) collecting the inert gas/gasoline vapor mixture from the headspace of the gasoline storage tank as the tank is refilled from a gasoline tanker truck; (d) cooling the inert gas/gasoline vapor mixture to a temperature sufficient to condense the gasoline vapor in the mixture to liquid gasoline but not sufficient to liquify the inert gas in the mixture; (e) separating the condensed liquid gasoline from the inert gas; and delivering the condensed liquid gasoline to a remote location for subsequent use.

Lievens, G.; Tiberi, T.P.

1993-06-22

233

SPILLS: An Evaporation/Air Dispersion Model for Chemical Spills on Land.  

National Technical Information Service (NTIS)

SPILLS, an unsteady-state model representing the evaporation of a chemical spill and the atmospheric dispersion of the vapors is presented. The model estimates concentrations of the vapors as a function of time and distance downwind of instantaneously-for...

M. T. Fleischer

1980-01-01

234

Comparative life-cycle air emissions of coal, domestic natural gas, LNG, and SNG for electricity generation.  

PubMed

The U.S. Department of Energy (DOE) estimates that in the coming decades the United States' natural gas (NG) demand for electricity generation will increase. Estimates also suggest that NG supply will increasingly come from imported liquefied natural gas (LNG). Additional supplies of NG could come domestically from the production of synthetic natural gas (SNG) via coal gasification-methanation. The objective of this study is to compare greenhouse gas (GHG), SOx, and NOx life-cycle emissions of electricity generated with NG/LNG/SNG and coal. This life-cycle comparison of air emissions from different fuels can help us better understand the advantages and disadvantages of using coal versus globally sourced NG for electricity generation. Our estimates suggest that with the current fleet of power plants, a mix of domestic NG, LNG, and SNG would have lower GHG emissions than coal. If advanced technologies with carbon capture and sequestration (CCS) are used, however, coal and a mix of domestic NG, LNG, and SNG would have very similar life-cycle GHG emissions. For SOx and NOx we find there are significant emissions in the upstream stages of the NG/ LNG life-cycles, which contribute to a larger range in SOx and NOx emissions for NG/LNG than for coal and SNG. PMID:17937317

Jaramillo, Paulina; Griffin, W Michael; Matthews, H Scott

2007-09-01

235

Comparative life-cycle air emissions of coal, domestic natural gas, LNG, and SNG for electricity generation  

SciTech Connect

The U.S. Department of Energy (DOE) estimates that in the coming decades the United States' natural gas (NG) demand for electricity generation will increase. Estimates also suggest that NG supply will increasingly come from imported liquefied natural gas (LNG). Additional supplies of NG could come domestically from the production of synthetic natural gas (SNG) via coal gasification-methanation. The objective of this study is to compare greenhouse gas (GHG), SOx, and NOx life-cycle emissions of electricity generated with NG/LNG/SNG and coal. This life-cycle comparison of air emissions from different fuels can help us better understand the advantages and disadvantages of using coal versus globally sourced NG for electricity generation. Our estimates suggest that with the current fleet of power plants, a mix of domestic NG, LNG, and SNG would have lower GHG emissions than coal. If advanced technologies with carbon capture and sequestration (CCS) are used, however, coal and a mix of domestic NG, LNG, and SNG would have very similar life-cycle GHG emissions. For SOx and NOx we find there are significant emissions in the upstream stages of the NG/LNG life-cycles, which contribute to a larger range in SOx and NOx emissions for NG/LNG than for coal and SNG. 38 refs., 3 figs., 2 tabs.

Paulina Jaramillo; W. Michael Griffin; H. Scott Matthews [Carnegie Mellon University, Pittsburgh, PA (United States). Civil and Environmental Engineering Department

2007-09-15

236

Electrolyte vapor condenser  

DOEpatents

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well.

Sederquist, Richard A. (Newington, CT); Szydlowski, Donald F. (East Hartford, CT); Sawyer, Richard D. (Canton, CT)

1983-01-01

237

BTSC VAPOR INSTRUSION PRIMER "VAPOR INTRUSION CONSIDERATION FOR REDEVELOPMENT"  

EPA Science Inventory

This primer is designed for brownfields stakeholders concerned about vapor intrusion, including property owners, real estate developers, and contractors performing environmental site investigations. It provides an overview of the vapor intrusion issue and how it can impact the ap...

238

Enthalpy of Vaporization and Vapor Pressures: An Inexpensive Apparatus  

ERIC Educational Resources Information Center

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

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

2007-01-01

239

Second Stage Intercooling Using LNG for Turbocharged Heavy Duty Road Vehicles Phase I Final Report  

SciTech Connect

It is well documented in engine performance literature that reduced engine inlet air temperature increases power output and reduces NO, emissions for both diesel and spark ignited (SI) engines. In addition, reduced inlet temperature increases the knock resistance of SI engines. In that most HD natural gas engines are SI derivatives of diesel engines it is appropriate to evaluate the benefits of reduced engine air temperature through LNG fuel. This project investigated the ''real world'' possibilities of a patented process for utilizing the ''cold'' in LNG to chill engine inlet air. The results support the conclusion that doing so is a practical means to increase engine power and reduce engine-out NO{sub x}.

None

1999-09-21

240

Propandiol vapor nucleation rates  

NASA Astrophysics Data System (ADS)

Consideration of vapor-gas nucleation as binary vapor nucleation (instead widely used the one component approximation for nucleation of this system now) may lead the progress in the development of nucleation theory. Observations of phase transitions initiated by the carrier gas in the critical embryos of condensate can be a sufficiently convincing argument in this discussion. In order to confirm the role of the carrier gases received in the recent research1, in present study 1,2-propanediol and 1,3-propanediol vapor nucleation rates were measured. Carbon dioxide (Tc=304.2 K,Pc=7.39 MPa) and sulfur hexafluoride (Tc=318.7 K,Pc=3.75 MPa) were chosen as the carrier gases, because of their low and convenient critical temperatures, Tc, and critical pressures, Pc. Analysis of the experimental data shows that gas-carrier molecules are involved in new phase embryo formation. Vapor nucleation of investigated substances in a carrier gas atmosphere can be considered as nucleation of binary system. .

Anisimov, M. P.; Nasibulin, A. G.; Timoshina, L. V.; Koropchak, J. A.

2000-08-01

241

Downhole vapor generator  

SciTech Connect

Disclosed is a method and apparatus for generating high pressure steam within a well bore for facilitating recovery of hydrocarbon deposits. The steam vapor generator is constructed for receiving high pressure water, fuel and oxidant in a downhole position for select mixing and combustion. High pressure water is received around a combustion chamber in an annular configuration and heated through a thermal wall region forming a lower portion thereof. The combustion chamber utilizes the heat energy of radiation to heat the water in the annular sleeve to the point of steam. The water sleeve further includes orifices for egress of the steam and a plurality of vent tubes within the water sleeve. The vent tubes extend substantially the length of the sleeve for receiving excess water vapor and/or undissolved gases created from the heat of vaporization and out-gassing. A collection chamber is provided beneath the combustion chamber in communication with the vent tubes and water sleeve for the mixing of the high pressure vapor and the exhaust thereof into the adjacent well formation.

Wyatt, W.G.

1984-04-17

242

Filter vapor trap  

Microsoft Academic Search

A sintered filter trap is adapted for insertion in a gas stream of sodium vapor to condense and deposit sodium thereon. The filter is heated and operated above the melting temperature of sodium, resulting in a more efficient means to remove sodium particulates from the effluent inert gas emanating from the surface of a liquid sodium pool. Preferably the filter

Guon; Jerold

1976-01-01

243

Active Hydrazine Vapor Sampler (AHVS).  

National Technical Information Service (NTIS)

The Active Hydrazine Vapor Sampler (AHVS) was developed to detect vapors of hydrazine (HZ) and monomethylhydrazine (MMH) in air at parts-per-billion (ppb) concentration levels. The sampler consists of a commercial personal pump that draws ambient air thro...

R. C. Young C. F. Mcbrearty D. J. Curran

1993-01-01

244

BioVapor Model Evaluation  

EPA Science Inventory

General background on modeling and specifics of modeling vapor intrusion are given. Three classical model applications are described and related to the problem of petroleum vapor intrusion. These indicate the need for model calibration and uncertainty analysis. Evaluation of Bi...

245

LNG cold energy use in agro-food industry: A case study in Sicily  

Microsoft Academic Search

It is known how the complete gasification of liquefied natural gas (LNG) can return about 230 kWh\\/t of energy. Nevertheless out of fifty-one gasification plants in the world, only thirty-one of them are equipped with systems for the partial recovery of the available energy. At the moment most of these plants mainly produce electric energy; however the employment of the cold

Antonio Messineo; Giuseppe Panno

2011-01-01

246

Comparison of CNG and LNG technologies for transportation applications. Final subcontract report, June 1991December 1991  

Microsoft Academic Search

This report provides a head-to-head comparison of compressed natural gas (CNG) and liquefied natural gas (LNG) supplied to heavy-duty vehicles. The comparison includes an assessment of the overall efficiency of the fuel delivery system, the cost of the fuel supply system, the efficiency of use in heavy-duty vehicles, and the environmental impact of each technology. The report concludes that there

Sinor

1992-01-01

247

Who knew? looks like we're in for an LNG glut  

SciTech Connect

U.S. domestic production of natural gas has grown considerably in the recent past, especially from unconventional domestic resources. Recession has reduced demand. Further, the U.S. may end up on the receiving end of much of the excess global production and transportation capacity because of its massive storage capacity. Charts of U.S. natural gas production and LNG imports are given.

NONE

2009-04-15

248

Combustion characteristics of mixture of anode off gas and LNG in reformer  

Microsoft Academic Search

Fuel processing system which converts hydrocarbon fuel into hydrogen rich gas (by stream reforming, partial oxidation, auto-thermal reforming) needs high temperature environment (600–1000°C). Generally, anode off gas or mixture of anode off gas and LNG are used as input gas for a fuel reformer. In order to constitute efficient and low emission burner system for fuel reformer, it is necessary

Jae Young Lee; Pil Hyong Lee; Chang Soo Park; Bong Il Park; Sang Soon Hwang

2011-01-01

249

Numerical analysis of 3-D flow through LNG marine control valves for their advanced design  

Microsoft Academic Search

A numerical analysis of three dimensional incompressible turbulent flows through high pressure drop control valves was carried\\u000a out by using a CFD-ACE code to develop anti-cavitation control valve used in LNG marine system. For this, numerical simulation\\u000a was performed on several models of control valve that have different orifice diameters of anti-trim and the size of valve\\u000a discharge. In this

Young Joon An; Byeong Jin Kim; Byeong Rog Shin

2008-01-01

250

Effects of the dispersion interaction in liquid water  

NASA Astrophysics Data System (ADS)

The properties of liquid water obtained from molecular simulations using a density functional theory (B3LYP) based force field [O. Akin-Ojo, F. Wang, J. Comput. Chem. 32 (2011) 453.] with and without an intermolecular dispersion interaction term are compared. Although it is small, the dispersion interaction is found to significantly affect some properties such as the density and the heat of vaporization but not others, for example, the atom-atom radial distribution functions and the infrared spectra. The inclusion of the dispersion interaction in the force field produces an increase in the computed self diffusivity comparable to that resulting from a ˜5 K rise in temperature.

Akin-Ojo, Omololu; Wang, Feng

2011-09-01

251

The Vapor Pressure of Barium.  

National Technical Information Service (NTIS)

The vapor pressure and the heat of vaporization of barium were measured using the Knudsen target technique. A recording microbalance was used to measure both the effusion rate and the recoil force exerted by the beam onto the target. The measured vapor pr...

P. D. Zavitsanos

1968-01-01

252

Dispersion Alloys (TEXUS 19).  

National Technical Information Service (NTIS)

An experiment to study the behavior of small non metallic particles dispersed in a metallic matrix during melting and directional solidification in microgravity is summarized. The samples consisting of pure Ag or of an Ag matrix with uniformly dispersed W...

W. Amende G. Vael

1991-01-01

253

Seed Dispersal 101  

NSDL National Science Digital Library

This two-minute radio program introduces listeners to the variety of agents that disperse seeds. The program's guest, a plant biologist, cites examples of nonliving and living dispersal agents that include the wind, water, and such animals as birds and bats. He also explains that a plant's fruits or seeds often offer clues about how they are dispersed. The program, which is available here in audio and text, is the first in a series about seed dispersal. Copyright 2005 Eisenhower National Clearinghouse

Planet, Pulse O.

2007-07-26

254

Dispersion y dinamica poblacional  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dispersal behavior of fruit flies is appetitive. Measures of dispersion involve two different parameter: the maximum distance and the standard distance. Standard distance is a parameter that describes the probalility of dispersion and is mathematically equivalent to the standard deviation around ...

255

Filter vapor trap  

DOEpatents

A sintered filter trap is adapted for insertion in a gas stream of sodium vapor to condense and deposit sodium thereon. The filter is heated and operated above the melting temperature of sodium, resulting in a more efficient means to remove sodium particulates from the effluent inert gas emanating from the surface of a liquid sodium pool. Preferably the filter leaves are precoated with a natrophobic coating such as tetracosane.

Guon, Jerold (Canoga Park, CA)

1976-04-13

256

Enceladus' water vapor plume.  

PubMed

The Cassini spacecraft flew close to Saturn's small moon Enceladus three times in 2005. Cassini's UltraViolet Imaging Spectrograph observed stellar occultations on two flybys and confirmed the existence, composition, and regionally confined nature of a water vapor plume in the south polar region of Enceladus. This plume provides an adequate amount of water to resupply losses from Saturn's E ring and to be the dominant source of the neutral OH and atomic oxygen that fill the Saturnian system. PMID:16527971

Hansen, Candice J; Esposito, L; Stewart, A I F; Colwell, J; Hendrix, A; Pryor, W; Shemansky, D; West, R

2006-03-10

257

Value off vapor extraction  

SciTech Connect

The remediation of a major gasoline spill affecting groundwater in a sole source aquifer required the use of various interrelated technologies. Estimate of the spill were as much as 4,000 m[sup 3] (1 mil gal) of gasoline from a single leaking pipe. Traditional and innovative technologies were investigated, piloted, designed, constructed, and operated for control and recovery of both pure and dissolved product, and contaminant vapors. Pure product recovery initially required an extensive static recovery system of pneumatic ejector pumps, supplemented with water table depression and product removal at one well. Dissolved product recovery and treatment also has been achieved by pumping this well to a temporary treatment facility prior to recharge to groundwater. Recovery and destruction of vapors emanating from the pure product into the vadose zone (the area above the permanent groundwater level) and the acceleration of product volatilization has been accomplished through the use of a vapor extraction and treatment facility using two bottom-burning flare units. Groundwater modeling results have been used to identify the scope of remedial efforts and to develop remedial alternatives. Implementation of the site remedial activities and operation of constructed facilities continues. 4 figs.

Gerbasi, P.J. (Roux Associates, Islandia, NY (United States)); Memoli, M.A. (Camp Dresser McKee, Woodbury, NY (United States))

1994-03-01

258

LNG Safety Research: FEM3A Model Development  

SciTech Connect

Work continued to address numerical problems experienced with simulation of low-wind-speed, stable, atmospheric conditions with FEM3A. Steps 1 through 8 in the plan outlined in the first Quarterly report have been completed successfully for the FEM3A model utilizing the Planetary Boundary Layer (PBL) turbulence closure model. Researchers at the University of Arkansas have solved the problems related to stability of the simulations at regulatory conditions of low wind speed and stable atmospheric conditions with FEM3A using the PBL model, and are continuing our program to verify the operation of the model using an updated, verified, version of the k-epsilon turbulence closure model which has been modified to handle dense gas dispersion effects. This quarterly report for DE-FG26-04NT42030 covers a period from January 1, 2006 to March 31, 2006. GTI's activities during the report quarter were limited to administrative work. The work at the University of Arkansas continued in line with the initial scope of work and the identified questions regarding surface to cloud heat transfer as being largely responsible for the instability problems previously encountered. A brief summary of results is discussed in this section and the complete report from University of Arkansas is attached.

Iraj A Salehi; Jerry Havens; Tom Spicer

2006-05-01

259

Studies on formation of unconfined detonable vapor cloud using explosive means.  

PubMed

Certain organic liquid fuels like hydrocarbons, hydrocarbon oxides, when dispersed in air in the form of small droplets, mix with surrounding atmosphere forming vapor cloud (aerosol) and acquire explosive properties. This paper describes the studies on establishment of conditions for dispersion of fuels in air using explosive means resulting in formation of detonable aerosols of propylene oxide and ethylene oxide. Burster charges based on different explosives were evaluated for the capability to disperse the fuels without causing ignition. Parameters like design of canister, burster tube, burster charge type, etc. have been studied based on dispersion experiments. The detonability of the aerosol formed by the optimized burster charge system was also tested. PMID:23618658

Apparao, A; Rao, C R; Tewari, S P

2013-03-21

260

Dispersion, controlled dispersion, and three applications  

NASA Astrophysics Data System (ADS)

Causality dictates that all physical media must be dispersive. (We will call a medium dispersive if its refractive index varies with frequency.) Ordinarily, strong dispersion is accompanied either by strong absorption or strong gain. However, over the past 15 years several groups have demonstrated that it is possible to have media that are both strongly dispersive and roughly transparent for some finite bandwidth. In these media, group and phase velocities may differ from each other by many orders of magnitude and even by sign. Relationships and intuitive models that are satisfactory when it is reasonable to neglect dispersion may then fail dramatically. In this dissertation we analyze three such cases of failure. Before looking at the specific cases, we review some basic ideas relating to dispersion. We review some of the geometric meanings of group velocity, touch on the relationship between group velocity and causality, and give some examples of techniques by which the group velocity may be manipulated. We describe the interplay between group velocity and energy density for non-absorbing dispersive media. We discuss the ideas of temporary absorption and emission as dictated by an instantaneous spectrum. We then apply these concepts in three specific areas. First, non-dispersive formulations for the momentum of light in a medium must be adjusted to account for dispersion. For over 100 years, there has been a gradual discussion of the proper form for the per-photon momentum. Two forms, each of which has experimental relevance in a 'dispersionless' medium, are the Abraham momentum, and the Minkowski momentum. If h is the angular frequency, n is the refractive index, h is Planck's constant, and c is the speed of light, then these reduce in a dispersionless medium to per-photon momenta of ho/(nc), and nho/c respectively. A simple generalization of the two momenta to dispersive media entails multiplying each per-photon momentum by n/ng, where ng is the group refractive index. The resulting forms are experimentally relevant for the case of the Abraham momentum, but not for the Minkowski momentum. We show how dispersion modulates the displacement of a sphere embedded in a dispersive medium by a pulse. Second, pulse transformation in a nonstationary medium is modulated by the presence of dispersion. Dispersion may enhance or mitigate the frequency response of a pulse to a changing refractive index, and if dispersion changes with time, the pulse bandwidth must change in a compensatory fashion. We introduce an explicit description of the kinetics of dispersive nonstationary inhomogeneous media. Using this description, we show how the group velocity can modulate the frequency response to a change in the refractive index and how Doppler shifts may become large in a dispersive medium as the velocity of the Doppler shifting surface approaches the group velocity. We explain a simple way to use existing technology to either compress or decompress a given pulse, changing its bandwidth and spatial extent by several orders of magnitude while otherwise preserving its envelope shape. We then introduce a dynamic descriptions of two simple media--one dispersive and one nondispersive. We compare the transformation of basic quantities like photon number, momentum density, and frequency by a temporal change in the refractive index in a specific non-dispersive medium to those wrought by a temporal change in the group refractive index in a specific dispersive medium. The differences between to media are fundamental and emphasize the salience of dispersion in the study of nonstationary media. Finally, we note that the nature of a single optical cavity quasimode depends on intracavity dispersion. We show that the quantum field noise associated with a single cavity mode may be modulated by dispersion. For a well-chosen mode in a high-Q cavity, this can amount to either an increase or a decrease in total vacuum field energy by several orders of magnitude. We focus on the "white light cavity," showing that the quantum noise of an ideal white

Bradshaw, Douglas H.

261

Vapor-Liquid Equilibria for Some Concentrated Aqueous PolymerSolutions  

SciTech Connect

Vapor-liquid-equilibrium data were obtained for binary aqueous solutions of six water-soluble linear polymers in the range 70-95 C. A classical gravimetric sorption method was used to measure the amount of solvent absorbed as a function of vapor-phase water pressure. Polymers studied were polyvinylpyrrolidone, polyethyleneoxide, polyvinylalcohol, hydroxyethylcellulose, polyethylenimine, polymethylvinylether. The experimental data were reduced with Hino's lattice model that distinguished the interactions due to London dispersion forces and those due to hydrogen bonding.

Striolo, Alberto; Prausnitz, John M.

1999-07-01

262

Heavy gas dispersion test summary report  

SciTech Connect

In this report, we describe the methods used to characterize the ambient meteorological conditions and the uncertainty associated with such parameters. We also discuss the various methods used to describe a dense-gas cloud as it disperses in the atmosphere, the reasons for using a variety of cloud parameters (in addition to cloud concentration) when dense-gas dispersion phenomena are occurring, and the parameters we selected to describe the characteristics of the cloud resulting from a continuous denser-than-air vapor release. Finally, we present the test summaries, including a brief description of the series from which the selected tests were chosen and extensive notes on how the cloud characteristics were obtained. 62 refs., 9 figs., 17 tabs.

Ermak, D.L.; Chapman, R.; Goldwire, H.C. Jr.; Gouveia, F.J.; Rodean, H.C.

1988-10-01

263

Heavy Gas Releases: Recent Dispersion Research.  

National Technical Information Service (NTIS)

The important liquefied fuels which form heavy gases are liquefied natural gas (LNG) (comprised chiefly of methane, but with small amounts of propane and ethane), and liquefied petroleum gas (LPG), (comprised of propane and butane in various ratios). In a...

J. H. Shinn D. L. Ermak R. P. Koopman

1981-01-01

264

Vapor cloud explosion analysis  

SciTech Connect

This paper introduces a new method (now commonly referred to as the Baker-Strehlow Method) for estimating pressure and impulse generated by vapor cloud explosions. Strehlow`s blast curves and concepts from the Multi-Energy method for determination of explosion energy are applied in this technique. New correlations for maximum flame speed based on obstacle density, fuel reactivity, and cloud confinement allow selection of the appropriate blast curve. Application of these correlations removes much of the subjectivity present in existing explosion estimates. 11 refs., 3 figs., 1 tab.

Baker, Q.A. [Wilfred Baker Engineering Inc., San Antonio, TX (United States); Tang, Ming Jun [Nanjing Univ. of Science and Technology (China); Scheier, E.A. [Occidental Chemical Corp., Dallas, TX (United States); Silva, G.J. [Occidental International Exploration & Production CO., Bakersfield, CA (United States)

1996-12-31

265

Tunable alkali metallic vapor laser  

Microsoft Academic Search

A tunable alkali metallic vapor laser system is disclosed. Stimulated Raman scattering (SRS) in a low pressure atomic alkali metallic vapor of potassium or cesium is utilized wherein the atomic vapor is provided and then primed to populate an intermediate level such as the 4Pââ level for potassium and the 6Pââ level for cesium from which the desired upper laser

I. Itzkan; R. T. V. Kung

1979-01-01

266

Analytical and experimental investigation of the dispersion process during rapid transients for the aluminum-based nuclear fuel plates  

SciTech Connect

A thermally induced fuel-plate dispersion model was developed to analyze for dispersive potential and determine the onset of fuel plate dispersion for aluminum-based research and test reactor fuels. The effect of rapid energy deposition in a fuel plate was simulated. Several data types for aluminum-based fuels tested in the Nuclear Safety Research Reactor (NSRR) facility in Japan and in the Transient Reactor Test (TREAT) facility in Idaho, US, were reviewed. Analyses of experiments show that the onset of fuel dispersion is clearly linked to a sharp rise in the predicted strain rate, which further coincides with the onset of aluminum vaporization. Analysis also shows that aluminum oxidation and exothermal chemical reaction between the fuel and aluminum can significantly affect: the energy deposition characteristics and, therefore dispersion onset connected with aluminum vaporization, and the onset of aluminum vaporization.

Georgevich, V.; Taleyarkhan, R.P.; Kim, S.H. [Oak Ridge National Lab., TN (United States); Fuketa, T.; Soyama, K.; Ishijima, K. [Japan Atomic Energy Research Inst., Takai, Ibaraki (Japan)

1995-06-01

267

Thermally induced dispersion mechanisms for aluminum-based plate-type fuels under rapid transient energy deposition  

SciTech Connect

A thermally induced dispersion model was developed to analyze for dispersive potential and determine onset of fuel plate dispersion for Al-based research and test reactor fuels. Effect of rapid energy deposition in a fuel plate was simulated. Several data types for Al-based fuels tested in the Nuclear Safety Research Reactor in Japan and in the Transient Reactor Test in Idaho were reviewed. Analyses of experiments show that onset of fuel dispersion is linked to a sharp rise in predicted strain rate, which futher coincides with onset of Al vaporization. Analysis also shows that Al oxidation and exothermal chemical reaction between the fuel and Al can significantly affect the energy deposition characteristics, and therefore dispersion onset connected with Al vaporization, and affect onset of vaporization.

Georgevich, V.; Taleyarkham, R.P.; Navarro-Valenti, S.; Kim, S.H.

1995-12-31

268

Biofiltration of methanol vapor.  

PubMed

Biofiltration of solvent and fuel vapors may offer a cost-effective way to comply with increasingly strict air emission standards. An important step in the development of this technology is to derive and validate mathematical models of the biofiltration process for predictive and scaleup calculations. For the study of methanol vapor biofiltration, an 8-membered bacterial consortium was obtained from methanol-exposed soil. The bacteria were immobilized on solid support and packed into a 5-cm-diameter, 60-cm-high column provided with appropriate flowmeters and sampling ports. The solid support was prepared by mixing two volumes of peat with three volumes of perlite particles (i.e., peat-perlite volume ratio 2:3). Two series of experiments were performed. In the first, the inlet methanol concentration was kept constant while the superficial air velocity was varied from run to run. In the second series, the air flow rate (velocity) was kept constant while the inlet methanol concentration was varied. The unit proved effective in removing methanol at rates up to 112.8 g h(-1) m(-3) packing. A mathematical model has been derived and validated. The model described and predicted experimental results closely. Both experimental data and model predictions suggest that the methanol biofiltration process was limited by oxygen diffusion and methanol degradation kinetics. PMID:18609582

Shareefdeen, Z; Baltzis, B C; Oh, Y S; Bartha, R

1993-03-01

269

Biofiltration of methanol vapor  

SciTech Connect

Biofiltration of solvent and fuel vapors may offer a cost-effective way to comply with increasingly strict air emission standards. An important step in the development of this technology is to derive and validate mathematical models of the biofiltration process for predictive and scaleup calculations. For the study of methanol vapor biofiltration, an 8-membered bacterial consortium was obtained from methanol-exposed soil. The bacteria were immobilized on solid support and packed into a 5-cm diameter, 60-cm-high column provided with appropriate flowmeters and sampling ports. The solid support was prepared by mixing two volumes of peat with three volumes of perlite particles. Two series of experiments were performed. In the first, the inlet methanol concentration was kept constant while the superficial air velocity was varied from run to run. In the second series, the air flow rate (velocity) was kept constant while the inlet methanol concentration was varied. The unit proved effective in removing methanol at rates up to 112.8 g h[sup [minus]1] m[sup [minus]3] packing. A mathematical model has been derived and validated. The model described and predicted experimental results closely. Both experimental data and model predictions suggest that the methanol biofiltration process was limited by oxygen diffusion and methanol degradation kinetics.

Shareefdeen, Z.; Baltzis, B.C. (New Jersey Inst. of Tech., Newark, (United States)); Oh, Youngsook; Bartha, R. (Rutgers, The State Univ. of New Jersey, New Brunswick (United States))

1993-03-05

270

Vapor transport in unsaturated soil columns: Implications for vapor extraction  

Microsoft Academic Search

A mathematical model was derived to examine the impact of gas advection, gas diffusion, gas-water mass transfer, gas-water partitioning, sorption, and intraaggregate diffusion on subsurface movement of organic vapors. Laboratory experiments were performed to determine the validity of the model and to investigate the impact of the various mechanisms on vapor transport. Columns were packed with a uniform Ottawa sand

John S. Gierke; Neil J. Hutzler; David B. McKenzie

1992-01-01

271

Modeling of near and supercritical droplet vaporization  

SciTech Connect

The model considers the case when a droplet, initially at ambient or elevated temperature, is suddenly injected into a gaseous environment that is at a temperature that is well above, and at a pressure that is slightly below (near-critical), or well above (super-critical) those corresponding to the critical value of the liquid. First, an analysis is developed of the diffusionally controlled evaporation of a fuel droplet at near and super-critical conditions. The transient conservation equations for the gas and liquid phases are solved using an expansion solution in a power series in time. The series expansion solution provides an explicit expression for the interface regression, the transient heat diffusion in the liquid and gas phases, and the mass transfer in the gas phase. An analysis of the super-critical, convective, evaporation of a fuel droplet in a stagnant point flow is developed next. The present analysis describes the transient evaporation of a liquid fuel at its stagnation point in a high temperature, high pressure, environment. The transient conservation equations for both liquid and gas phases are solved simultaneously to determine the profiles of the vorticity, temperature and species distributions, and the regression velocity of the liquid-gas interface. A third model is developed of the dispersion of a vapor fuel droplet that is suddenly set in motion in a gaseous environment that has a density similar to that of the fuel vapor. In the analysis, the transient, axisymmetric, stream function-vorticity and species equations are solved to determine the evolution of the vorticity distribution, species mixing and the distortion of the initial interface. The results show that the initially spherical gaseous fuel droplet is extensively distorted, adopting a mushroom-like shape, and also the vapor mixing process is greatly enhanced around the vortex ring.

Lee, H.

1987-01-01

272

Passive vapor extraction feasibility study.  

National Technical Information Service (NTIS)

Demonstration of a passive vapor extraction remediation system is planned for sites in the 200 West Area used in the past for the disposal of waste liquids containing carbon tetrachloride. The passive vapor extraction units will consist of a 4-in.-diamete...

V. J. Rohay

1994-01-01

273

The atmospheric water vapor line  

Microsoft Academic Search

We have measured the hydrogen and oxygen isotope composition of atmospheric water vapor periodically across the American Southwest through most of 2007. Samples were primarily collected over Albuquerque, NM on the roof of the 3-story UNM geology building on a near-daily basis with occasional sampling in southern Arizona and southern Texas. Water vapor was captured by pumping ~60 to ~600

M. Strong; Z. D. Sharp; D. S. Gutzler

2008-01-01

274

A Column Dispersion Experiment.  

ERIC Educational Resources Information Center

|Crushed glass and a Rhodamine B solution are used in a one-dimensional optically scanned column experiment to study the dispersion phenomenon in porous media. Results indicate that the described model gave satisfactory results and that the dispersion process in this experiment is basically convective. (DC)|

Corapcioglu, M. Y.; Koroglu, F.

1982-01-01

275

Laws of Dispersion.  

National Technical Information Service (NTIS)

Two problems on the laws of dispersion for materials such as small particles and gas bubbles in turbulent streams are considered. After discussing the mechanisms of single-particle dispersion, a statistical approximation model is used to calculate two-par...

R. L. Peskin E. L. Krasnoff

1969-01-01

276

Turbulent Relative Dispersion  

Microsoft Academic Search

This review begins with the classical foundations of relative dispersion in Kolmogorov's similarity scaling. Analysis of the special cases of isotropic and homogeneous scalar fields is then used to establish most simply the connection with turbulent mixing. The importance of the two-particle acceleration covariance in relative dispersion is demonstrated from the kinematics of the motion of particle-pairs. A summary of

Brian Sawford

2001-01-01

277

Passive dispersal in arachnids  

Microsoft Academic Search

Some arachnids (spiders, mites and pseudoscorpions) are able to use both active and passive dispersal. The best-known passive dispersal method in arachnids is called ëballooningí and starts with ëtiptoe behaviourí. Using threads of silk, spiders can move from place to place with air currents. Usually the spider aeronauts are small, but sometimes larger ones can also be transported in this

DARIA BAJERLEIN

2007-01-01

278

Dispersal by macroalgae  

Microsoft Academic Search

Seaweed dispersal is discussed in relation to the properties of the propagules, the parent plant and the water motion. The magnitude of water flow velocities is overwhelmingly important. Even motile propagules have little control over their destiny. The fate of both liberated propagules and drifting plants is discussed in relation to dispersal distance and the likelihood of successful colonization at

T. A. Norton

1992-01-01

279

THERMALLY OPERATED VAPOR VALVE  

DOEpatents

A valve is presented for use in a calutron to supply and control the vapor to be ionized. The invention provides a means readily operable from the exterior of the vacuum tank of the apparatuss without mechanical transmission of forces for the quick and accurate control of the ionizing arc by a corresponding control of gas flow theretos thereby producing an effective way of carefully regulating the operation of the calutron. The invention consists essentially of a tube member extending into the charge bottle of a calutron devices having a poppet type valve closing the lower end of the tube. An electrical heating means is provided in the valve stem to thermally vary the length of the stem to regulate the valve opening to control the flow of material from the charge bottle.

Dorward, J.G. Jr.

1959-02-10

280

Tested Demonstrations. Gasoline Vapor: An Invisible Pollutant  

ERIC Educational Resources Information Center

|Describes a demonstration concerning the air pollution aspects of gasoline vapor which provides an estimation of the vapor pressure of test fuel, the molecular weight of the vapor, and illustrates a method of controlling the pollution. (SL)|

Stephens, Edgar R.

1977-01-01

281

Natural gas and CO2 price variation: impact on the relative cost-efficiency of LNG and pipelines  

Microsoft Academic Search

This article develops a formal model for comparing the cost structure of the two main transport options for natural gas: liquefied natural gas (LNG) and pipelines. In particular, it evaluates how variations in the prices of natural gas and greenhouse gas emissions affect the relative cost-efficiency of these two options. Natural gas is often promoted as the most environmentally friendly

Marte Ulvestad; Indra Overland

2012-01-01

282

Comparative life-cycle air emissions of coal, domestic natural gas, LNG, and SNG for electricity generation  

Microsoft Academic Search

The U.S. Department of Energy (DOE) estimates that in the coming decades the United States' natural gas (NG) demand for electricity generation will increase. Estimates also suggest that NG supply will increasingly come from imported liquefied natural gas (LNG). Additional supplies of NG could come domestically from the production of synthetic natural gas (SNG) via coal gasification-methanation. The objective of

Paulina Jaramillo; W. Michael Griffin; H. Scott Matthews

2007-01-01

283

78 FR 17189 - Trunkline LNG Export, LLC; Application for Long-Term Authorization to Export Liquefied Natural...  

Federal Register 2010, 2011, 2012, 2013

...domestically produced LNG to FTA countries has been reviewed pursuant...proposed export to non-FTA countries, TLNG Export [[Page 17192...authorization to non-FTA countries conditioned on the FERC's...impact on the U.S. economy (GDP), consumers, and...

2013-03-20

284

MODIFICATION OF SPILL FACTORS AFFECTING AIR POLLUTION. VOLUME I. AN EVALUATION OF COOLING AS A VAPOR MITIGATION PROCEDURE FOR SPILLED VOLATILE CHEMICALS  

EPA Science Inventory

Spilled chemicals that pose a hazard to the land and water ecosystems can also provide a significant vapor hazard. Although the vapors released by such chemicals may ultimately be dispersed in the environment with little long-term effects, they do pose a hazard to life and proper...

285

Anomalous dispersion in atomic line filters applied for spatial frequency detection  

SciTech Connect

The anomalous dispersion of an atomic line filter near a resonant transition is exploited for full-field frequency measurements. The influence of the line shape function on the dispersion in atomic vapors near resonance and the possibilities to increase sensitivity are discussed. From the model-calculated absorption of iodine vapor at frequency-doubled Nd:YAG laser wavelengths, the corresponding refractive index is obtained through the Kramers-Kronig relations. Both variables are used to assess the performance of a iodine vapor cell as a dispersive element in an interferometric setup for Doppler frequency shift detection. With good agreement, the predicted sensitivity of the setup is compared to an experimental calibration. Observed discrepancies are attributed to the assumption of a Gaussian line shape in the absorption model. The full-field Doppler frequency measurement capacity of the technique is demonstrated in a rotating disk experiment, and the measurement performance is assessed.

Landolt, Andrin; Roesgen, Thomas

2009-11-01

286

Dispersion in isotachophoresis  

NASA Astrophysics Data System (ADS)

Isotachophoresis (ITP) is a widely used separation and preconcentration technique, which has been utilized in numerous applications including drug discovery, toxin detection, and food analysis. In ITP, analytes are segregated and focused between relatively high mobility leading ions and relatively low mobility trailing ions. These electromigration dynamics couple with advective processes associated with non-uniform electroosmotic flow (EOF). The latter generates internal pressure gradients leading to strong dispersive fluxes. This dispersion is nearly ubiquitous and currently limits the sensitivity and resolution of typical ITP assays. Despite this, there has been little work studying these coupled mechanisms. We performed an analytical and experimental study of dispersion dynamics in ITP. To achieve controlled pressure gradients, we suppressed EOF and applied an external pressure head to balance electromigration. Under these conditions, we show that radial electromigration (as opposed to radial diffusion as in Taylor dispersion) balances axial electromigration. To validate the analysis, we monitored the shape of a focusing fluorescent zone as a function of applied electric field. These experiments show that ITP dispersion may result in analyte widths an order of magnitude larger than predicted by the typical non-dispersive theory. Our goal is to develop a simplified dispersion model to capture this phenomenon, and to implement it in a numerical solver for general ITP problems.

Bercovici, Moran; Santiago, Juan G.

2008-11-01

287

Water vapor measurement and compensation in the near- and mid-infrared with the Keck Interferometer Nuller  

NASA Astrophysics Data System (ADS)

Water vapor is the dominant source of randomly-changing atmospheric dispersion on timescales of seconds to minutes in the near- and mid-infrared. The dispersion changes are sufficient to limit the performance of the Keck Nuller unless steps are taken to measure and compensate for them. Here we present the first measurements of water vapor differential column fluctuations with the mid-infrared Keck Nuller and its near-infrared fringe tracker, taken in October 2005, and discuss theoretical and practical aspects of our dispersion feedforward implementation. The data show much larger fluctuations than were seen in median Mauna Kea conditions measured at radio wavelengths, and probably account for the generally poor performance of the Nuller during the observing run. The measurements in the two bands show strong correlations, indicating that the planned feedforward of the near-infrared value to stabilize the dispersion in the mid-infrared will substantially reduce the residual dispersion fluctuations seen by the Nuller.

Koresko, Chris; Colavita, M. Mark; Serabyn, Eugene; Booth, Andrew; Garcia, Jean

2006-07-01

288

Peak broadening from an electrothermal vaporization sample introduction source into an inductively coupled plasma  

Microsoft Academic Search

Signal broadening using electrothermal vaporization with inductively coupled mass spectrometry (ETV-ICPMS) occurs at a rate much faster than would be predicted by simple longitudinal diffusion. A Monte Carlo simulation that focused on particle motion within the transport tubing was created to elucidate the causes of this dispersion within ETV-ICPMS. Several parameters, including the diffusion coefficient, tube diameter, transport tube length,

John Venable; James A Holcombe

2001-01-01

289

VAPOR SHIELD FOR INDUCTION FURNACE  

DOEpatents

This patent relates to a water-cooled vapor shield for an inductlon furnace that will condense metallic vapors arising from the crucible and thus prevent their condensation on or near the induction coils, thereby eliminating possible corrosion or shorting out of the coils. This is accomplished by placing, about the top, of the crucible a disk, apron, and cooling jacket that separates the area of the coils from the interior of the cruclbIe and provides a cooled surface upon whlch the vapors may condense.

Reese, S.L.; Samoriga, S.A.

1958-03-11

290

Relativistic Plasma Dispersion Relation.  

National Technical Information Service (NTIS)

The relativistic plasma dispersion relation for waves propagating perpendicular to a constant magnetic field is transformed into a rapidly converging series of integrals. Landau damping of the electrostatic waves is recovered in the limit of zero magnetic...

B. N. A. Lamborn

1969-01-01

291

Relativistic plasma dispersion relation  

Microsoft Academic Search

The relativistic plasma dispersion relation for waves propagating perpendicular to a constant magnetic field is transformed into a rapidly converging series of integrals. Landau damping of the electrostatic waves is recovered in the limit of zero magnetic field.

B N A Lamborn; B. N. A

1969-01-01

292

Seafood Safety and Dispersants  

Center for Food Safety and Applied Nutrition (CFSAN)

Text Version... NOAA and EPA have analyzed 2,195 water samples in the deep waters of the Gulf for components of dispersants. Only ... More results from www.fda.gov/downloads/food/recallsoutbreaksemergencies

293

Dispersion strengthened copper  

DOEpatents

A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

Sheinberg, Haskell (Los Alamos, NM); Meek, Thomas T. (Knoxville, TN); Blake, Rodger D. (Santa Fe, NM)

1990-01-01

294

Dispersion strengthened copper  

DOEpatents

A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

Sheinberg, Haskell (Los Alamos, NM); Meek, Thomas T. (Knoxville, TN); Blake, Rodger D. (Santa Fe, NM)

1989-01-01

295

Archimedes Mass Filter Vaporizer  

NASA Astrophysics Data System (ADS)

Archimedes Technology Group, Inc., is developing a plasma mass separator called the Archimedes Filter that separates waste oxide mixtures ion by ion into two mass groups: light and heavy. Since high-level waste at Hanford has 99.9its radioactivity associated with heavy elements, the Archimedes Filter can effectively decontaminate over three-quarters of that waste. The Filter process involves some preprocessing followed by volatilization and separation by the magnetic and electric fields of the main plasma. This presentation describes the approach to volatilization of the waste oxy-hydroxide mixture by means of a very high heat flux (q > 10 MW/m2). Such a high heat flux is required to ensure congruent evaporation of the complex oxy-hydroxide mixture and is achieved by injection of small droplets of molten waste into an inductively coupled plasma (ICP) torch. This presentation further addresses different issues related to evaporation of the waste including modeling of droplet evaporation, estimates of parameters of plasma torch, and 2D modeling of the plasma. The experimental test bed for oxide vaporization and results of the initial experiments on oxide evaporation in 60 kW ICP torch will also be described.

Putvinski, S.; Agnew, A. F.; Cluggish, B. P.; Ohkawa, T.; Sevier, L.; Umstadter, K. R.; Dresvin, S. V.; Kuteev, B. V.; Feygenson, O. N.; Ivanov, D. V.; Zverev, S. G.; Miroshnikov, I. V.; Egorov, S. M.; Kiesewetter, D. V.; Maliugin, V. I.

2001-10-01

296

Poly(phenylenediamine) Dispersions  

Microsoft Academic Search

The formation and properties of poly(phenylenediamine) colloidal dispersions were investigated. Oxidative dispersion polymerization of 1,3-phenylenediamine dihydrochloride stabilized with poly(N-vinylpyrrolidone) was taken as a reference experiment. Conductivity, temperature, and acidity of the reaction mixture were recorded during the polymerization. Oxidations of all three phenylenediamine bases, of corresponding dihydrochlorides, and of dihydrochlorides in excess acid are compared. The effect of the nature

Tetyana Sulimenko; Jaroslav Stejskal; Jan Prokeš

2001-01-01

297

Water Vapor Diffusion Membrane Development.  

National Technical Information Service (NTIS)

A total of 18 different membranes were procured, characterized, and tested in a modified bench-scale vapor diffusion water reclamation unit. Four membranes were selected for further studies involving membrane fouling. Emphasis was placed on the problem of...

M. K. Tan

1976-01-01

298

Portable vapor diffusion coefficient meter  

DOEpatents

An apparatus for measuring the effective vapor diffusion coefficient of a test vapor diffusing through a sample of porous media contained within a test chamber. A chemical sensor measures the time-varying concentration of vapor that has diffused a known distance through the porous media. A data processor contained within the apparatus compares the measured sensor data with analytical predictions of the response curve based on the transient diffusion equation using Fick's Law, iterating on the choice of an effective vapor diffusion coefficient until the difference between the predicted and measured curves is minimized. Optionally, a purge fluid can forced through the porous media, permitting the apparatus to also measure a gas-phase permeability. The apparatus can be made lightweight, self-powered, and portable for use in the field.

Ho, Clifford K. (Albuquerque, NM)

2007-06-12

299

Understanding Latent Heat of Vaporization.  

ERIC Educational Resources Information Center

Presents a simple exercise for students to do in the kitchen at home to determine the latent heat of vaporization of water using typical household materials. Designed to stress understanding by sacrificing precision for simplicity. (JRH)

Linz, Ed

1995-01-01

300

Vapor sampling and analysis plan.  

National Technical Information Service (NTIS)

This document is a plan which serves as the contractual agreement between the Characterization Program, Sampling Operations, Oak Ridge National Laboratory, and PNL tank vapor program. The scope of this plan is to provide guidance for the sampling and anal...

C. S. Homi

1995-01-01

301

Preprototype Vapor Compression Distillation Subsystem.  

National Technical Information Service (NTIS)

A three-person capacity preprototype vapor compression distillation subsystem for recovering potable water from wastewater aboard spacecraft was designed, assembled, and tested. The major components of the subsystem are: (1) a distillation unit which incl...

G. S. Ellis R. A. Wynveen F. H. Schubert

1979-01-01

302

Landfill Gas Conversion to LNG and LCO{sub 2}. Phase II Final Report for January 25, 1999 - April 30, 2000  

SciTech Connect

This report summarizes work on the development of a process to produce LNG (liquefied methane) for heavy vehicle use from landfill gas (LFG) using Acrion's CO{sub 2} wash process for contaminant removal and CO{sub 2} recovery.

Brown, W. R.; Cook, W. J.; Siwajek, L. A.

2000-10-20

303

Experimental study on flow boiling heat transfer of LNG in a vertical smooth tube  

NASA Astrophysics Data System (ADS)

An experimental apparatus is set up in this work to study the upward flow boiling heat transfer characteristics of LNG (liquefied natural gas) in vertical smooth tubes with inner diameters of 8 mm and 14 mm. The experiments were performed at various inlet pressures from 0.3 to 0.7 MPa. The results were obtained over the mass flux range from 16 to 200 kg m-2 s-1 and heat fluxes ranging from 8.0 to 32 kW m-2. The influences of quality, heat flux and mass flux, tube diameter on the heat transfer characteristic are examined and discussed. The comparisons of the experimental heat transfer coefficients with the predicted values from the existing correlations are analyzed. The correlation by Zou et al. [16] shows the best accuracy with the RMS deviation of 31.7% in comparison with the experimental data.

Chen, Dongsheng; Shi, Yumei

2013-10-01

304

Cauchy's dispersion equation reconsidered : dispersion in silicate glasses.  

SciTech Connect

We formulate a novel method of characterizing optically transparent substances using dispersion theory. The refractive index is given by a generalized Cauchy dispersion equation with coefficients that are moments of the uv and ir absorptions. Mean dispersion, Abbe number, and partial dispersion are combinations of these moments. The empirical relation between index and dispersion for families of glasses appears as a consequence of Beer's law applied to the uv spectra.

Smith, D. Y.; Inokuti, M.; Karstens, W.; Physics; Univ. of Vermont; St. Michael's College

2002-01-01

305

Atomization and vaporization characteristics of airblast fuel injection inside a venturi tube  

NASA Astrophysics Data System (ADS)

This paper describes the experimental and numerical characterization of the capillary fuel injection, atomization, dispersion, and vaporization of liquid fuel in a coflowing air stream inside a single venturi tube. The experimental techniques used are all laser-based. Phase Doppler analyzer was used to characterize the atomization and vaporization process. Planar laser-induced fluorescence visualizations give good qualitative picture of the fuel droplet and vapor distribution. Limited quantitative capabilities of the technique are also demonstrated. A modified version of the KIVA-II was used to simulate the entire spray process, including breakup and vaporization. The advantage of venturi nozzle is demonstrated in terms of better atomization, more uniform F/A distribution, and less pressure drop. Multidimensional spray calculations can be used as a design tool only if care is taken for the proper breakup model, and wall impingement process.

Sun, H.; Chue, T.-H.; Lai, M.-C.; Tacina, R. R.

1993-06-01

306

Ordered micro-porous carbon molecular sieves containing well-dispersed platinum nanoparticles for hydrogen storage  

Microsoft Academic Search

Ordered micro-porous carbon molecular sieves containing highly dispersed platinum nanoparticles with tunable sizes from 1 to 6nm are synthesized in this work. The synthesis is simply realized by nanocasting of furfuryl alcohol precursor on Pt-impregnated NaY zeolite hard templates and complemented by chemical vapor deposition by propylene gas. During the carbonization, Pt ions can be reduced to form highly dispersed

Yun-Xia Yang; Laure Bourgeois; Chunxia Zhao; Dongyuan Zhao; Alan Chaffee; Paul A. Webley

2009-01-01

307

The atmospheric water vapor line.  

NASA Astrophysics Data System (ADS)

We have measured the hydrogen and oxygen isotope composition of atmospheric water vapor periodically across the American Southwest through most of 2007. Samples were primarily collected over Albuquerque, NM on the roof of the 3-story UNM geology building on a near-daily basis with occasional sampling in southern Arizona and southern Texas. Water vapor was captured by pumping ~60 to ~600 liters of air (amount depending on dew point) through a cold trap, producing ~1mL of water. Precipitation samples were also collected in Albuquerque throughout the year and analyzed for hydrogen and oxygen isotopic composition. Isotopic compositions of both vapor and precipitation were determined by CO2 equilibration for oxygen and chromium reduction for hydrogen, with resulting gasses analyzed on a mass spectrometer. Nearly all water vapor samples lie parallel to the Global Meteoric Water Line (GMWL) but with a deuterium excess of ~17 (?D = 8?O + 17). This is true regardless of relative humidity, dew point, location, time of day, or season. Precipitation samples fall to the right of the GMWL with a slope of ~5. Within our dataset we have identified 10 pairs of vapor and precipitation samples that were collected within 24 hours. Half of these sample pairs have values consistent with equilibrium conditions at ground temperature, while the other half are not in equilibrium at any temperature. Simple modeling of nonequilibrium fractionation processes suggests that the array of precipitation samples can be derived from the array of vapor samples by equilibrium condensation followed by partial evaporation of falling raindrops. Our data suggests that atmospheric water vapor has a relatively constant deuterium excess value regardless of moisture source, degree of rainout, and/or evapotranspiration contributions.

Strong, M.; Sharp, Z. D.; Gutzler, D. S.

2008-12-01

308

Seed Dispersal: Lemurs  

NSDL National Science Digital Library

Trees in Madagascar's forests have evolved traits that promote the dispersal of their seeds by lemurs. This two-minute radio program focuses on the interaction between forest plants and lemurs--the main seed dispersers in the forests. A guest scientist explains why lemurs ingest seeds that are large relative to their body size. He also notes that the fruits of Madagascar's trees have evolved to be strong smelling but drably colored in accordance with lemurs' keen sense of smell and poor vision. The program is available in text and audio formats. The latter includes audio of ring-tailed lemurs. Copyright 2005 Eisenhower National Clearinghouse

Planet, Pulse O.

2007-09-20

309

Calibration of an explosives vapor generator based on vapor diffusion from a condensed phase.  

National Technical Information Service (NTIS)

Development of a vapor generator for consistently producing accurate amounts of vapor from low vapor pressure explosive materials is a pressing need within the explosives detection community. Of particular importance for reproducibility and widespread acc...

J. E. Parmeter L. Rhykerd F. J. Conrad G. S. Tiano D. Preston

1995-01-01

310

Thermoeconomic analysis of a novel zero-CO 2-emission high-efficiency power cycle using LNG coldness  

Microsoft Academic Search

This paper presents a thermoeconomic analysis aimed at the optimization of a novel zero-CO2 and other emissions and high-efficiency power and refrigeration cogeneration system, COOLCEP-S (Patent pending), which uses the liquefied natural gas (LNG) coldness during its revaporization. It was predicted that at the turbine inlet temperature (TIT) of 900°C, the energy efficiency of the COOLCEP-S system reaches 59%. The

Meng Liu; Noam Lior; Na Zhang; Wei Han

2009-01-01

311

Vapor mixture generation for infrared sensor evaluation  

NASA Astrophysics Data System (ADS)

The use of the equilibrium vapor cell method quantitatively supplies one or more analytes in the presence of water vapor by using the vapor liquid equilibrium properties of aqueous solutions to delivery target vapors. This study demonstrates vapor generation of ammonia, ethanol, and ammonia/ethanol mixtures from aqueous solutions. Gravimetrically prepared aqueous solutions of ethanol and/or ammonia along with vapor liquid equilibrium data permits assessment of the mixed vapor target amounts delivered into an optical cell. Acquisition of the infrared vapor phase spectra is completed with a laboratory spectrometer for the target vapors in the Beer's law concentration region using a fixed pathlength optical cell. Even though ideal solution behavior is assumed for the ethanol/ammonia interactions in the ternary solutions, the infrared spectral results between the binary and ternary solutions are shown to compare favorably.

Field, Paul E.; Combs, Roger J.

312

Electrical Breakdown in Water Vapor  

NASA Astrophysics Data System (ADS)

In this paper investigations of the voltage required to break down water vapor are reported for the region around the Paschen minimum and to the left of it. In spite of numerous applications of discharges in biomedicine, and recent studies of discharges in water and vapor bubbles and discharges with liquid water electrodes, studies of the basic parameters of breakdown are lacking. Paschen curves have been measured by recording voltages and currents in the low-current Townsend regime and extrapolating them to zero current. The minimum electrical breakdown voltage for water vapor was found to be 480 V at a pressure times electrode distance (pd) value of around 0.6 Torr cm (˜0.8 Pa m). The present measurements are also interpreted using (and add additional insight into) the developing understanding of relevant atomic and particularly surface processes associated with electrical breakdown.

Škoro, N.; Mari?, D.; Malovi?, G.; Graham, W. G.; Petrovi?, Z. Lj.

2011-11-01

313

Electrical Breakdown in Water Vapor  

SciTech Connect

In this paper investigations of the voltage required to break down water vapor are reported for the region around the Paschen minimum and to the left of it. In spite of numerous applications of discharges in biomedicine, and recent studies of discharges in water and vapor bubbles and discharges with liquid water electrodes, studies of the basic parameters of breakdown are lacking. Paschen curves have been measured by recording voltages and currents in the low-current Townsend regime and extrapolating them to zero current. The minimum electrical breakdown voltage for water vapor was found to be 480 V at a pressure times electrode distance (pd) value of around 0.6 Torr cm ({approx}0.8 Pa m). The present measurements are also interpreted using (and add additional insight into) the developing understanding of relevant atomic and particularly surface processes associated with electrical breakdown.

Skoro, N.; Maric, D.; Malovic, G.; Petrovic, Z. Lj. [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia); Graham, W. G. [Centre for Plasma Physics, School of Mathematics and Physics, Queens University Belfast, BT7 1NN (United Kingdom)

2011-11-15

314

Estimating Change in Dispersion.  

ERIC Educational Resources Information Center

|Statistical methods are presented for: (1) studying changes in dispersion (CID) of a dependent measure over time; (2) estimating the effects of treatments on the rate of CID; and (3) combining such estimated effects from related studies. Focus is on the logic of estimating CID using log transformation-based analyses. (SLD)|

Raudenbush, Steven W.

1988-01-01

315

Radiological Dispersion Device (RDD)  

MedlinePLUS

... far more likely than use of a nuclear explosive device. An RDD combines a conventional explosive device — such as a bomb — with radioactive material. ... an Radiological Dispersion Device (RDD) Event While the explosive blast will be immediately obvious, the presence of ...

316

Dispersal of First  

Microsoft Academic Search

Many ``workers'' in north temperate colonies of the eusocial paper wasp Polistes fuscatus disappear within a few days of eclosion. We provide evidence that these females are pursuing an alternative reproductive strategy, i.e., dispersing to overwinter and become nest foundresses the following spring, instead of helping to rear brood on their natal nests. A female is most likely to stay

H. Kern Reeve; John M. Peters; Peter Nonacs; Philip T. Starks

1998-01-01

317

Dispersive Fourier transform spectroscopy  

Microsoft Academic Search

Dispersive Fourier transform spectroscopy (DFTS) is a technique for determining the optical constants of solids, liquids and gases from direct measurements of both the amplitude and phase of either their reyection or transmission coeficients. Measurements are usually made at normal incidence with the specimen in one arm of a Michelson interferometer. The technique has been widely used for measurements in

T. J. Parker

1990-01-01

318

FEDS Smoke Dispersion.  

National Technical Information Service (NTIS)

The report discusses the design and test of a Smoke Generator system for use in Forced Entry deterrence. The system is designed for rapid dispersion of opaque black smoke without excessive heat or sparks and is provided for magazine 'safe' operation.

L. L. Paxson

1979-01-01

319

Mitigation of Shocks by Finely Dispersed Particles  

NASA Astrophysics Data System (ADS)

Effectively minimizing the damage due to onboard explosions and blast waves on naval ships has always been a priority to the Navy. Water mist presents a clean method for mitigating the effects of the blast wave. However, the effectiveness of water mist in mitigating blast waves is not well understood. As a first step towards determining the effectiveness of water droplets on mitigating blasts, we investigate the ability of particles and droplets to mitigate shock waves in tubes. An explicit, unsteady, flux-corrected transport technique is used for the gas-phase conservation equations, and an Eulerian sectional approach is used for the dispersed-phase. The sectional approach accounts for drag, heat-transfer from the gas to the particles using an infinite conductivity model, and vaporization of the particles. Shock-tube simulations were carried out to match an experimental set up for which some data on shock interaction with particles is available. Several simulations were conducted to examine the effects of driver section length, particle size, heat-transfer effects, and vaporization effects on the mitigation of the front shock, to give a full picture of the mitigation process and the important parameters and processes. Results are in good agreement with available data and suggest that for all cases with particles the shock is slowed, reaching an "equilibrium" shock Mach number far downstream of the original diaphragm.

Schwer, D. A.; Kailasanath, K.

2002-11-01

320

Copper vapor laser precision processing  

NASA Astrophysics Data System (ADS)

Copper vapor laser (CVL) was designed on the basis master oscillator (MO) - spatial filter - amplifier (AMP) system which is placed in thermostable volume. Processing material is moved by means of CNC system GPM-AP-400 with +/- 5 micrometers accuracy. Several cutting parameters are considered which define the quality and productivity of vaporization cutting: efficiency, cutwidth, height of upper and lower burr, roughness, laser and heat affected zones. Estimates are made for some metals with thickness 0.02 - 0.3 mm and cutwidth 0.01 - 0.03 mm. The examples of workpieces produced by CVL are presented.

Nikonchuk, Michail O.

1991-05-01

321

Measurements of 1\\/f frequency noise reduction in semiconductor lasers using optical feedback with dispersive loss  

Microsoft Academic Search

The authors review the theoretical framework for linewidth reduction in semiconductor lasers using optical feedback with dispersive loss. These results are then applied to lasers having both white and 1\\/f frequency noise. Experimental confirmation of the dependence of frequency noise on feedback parameters is presented using optical feedback from an external cavity containing Cs vapor. It is shown that such

J. Kitching; Yaakov Shevy; J. Iannelli; Amnon Yariv

1993-01-01

322

Venus Balloons using Water Vapor  

Microsoft Academic Search

We propose an inflatable balloon using water vapor for the lifting gas, which is liquid in the transportation stage before entry into the high temperature atmosphere. The envelope of the balloon has an outer layer for gas barrier (a high-temperature resistant film) and an inner layer for liquid water keeping. In the descent stage using a parachute, water widely held

N. Izutsu; N. Yajima; H. Honda; T. Imamura

2002-01-01

323

Vaporization means for liquid fuel  

Microsoft Academic Search

In vaporization means for liquid fuel for an internal combustion engine, the mixture strength is measured and used to control the rate of flow of liquid fuel into the air stream so as to maintain the mixture strength constant. Measurement of mixture strength is effected by measuring the temperature drop in the air flow due to the latent heat of

1981-01-01

324

Vaporized liquid fuel combustion apparatus  

Microsoft Academic Search

This patent describes a vaporized liquid fuel combustion apparatus comprising: a cylinder defining a combustion chamber, the cylinder having an inlet end for receipt of combustion air, a first flange surrounding the inlet end and an outlet end for exhausting gaseous combustion products; means for introducing the fuel into the combustion chamber and ignition means exposed to the combustion chamber

Y. Kimijima; K. Kikuchi

1986-01-01

325

INDOOR AIR VAPOR INTRUSION SEMINAR  

EPA Science Inventory

This seminar is sponsored by the ORD in collaboration with the Office of Solid Waste and Emergency Response. The goal of this seminar is to present information and guidance to evaluate, assess and characterize chemical vapor pathways migrating into structures resulting from conta...

326

Physical vapor deposition tool coatings  

Microsoft Academic Search

Physical vapor deposition (PVD) of hard coatings such as titanium nitride have been an industrial reality since the beginning of the 1980s. Two PVD processes, low voltage electron beam and cathodic arc deposition, were responsible for the early commercial success of hard coatings on high speed steel tooling. Since that time, two other PVD processes have also been prosperous in

William D. Sproul

1996-01-01

327

Low Temperature Vapor Growth Studies.  

National Technical Information Service (NTIS)

Topics include: room temperature polishing of Ge and GaAs using NaOCl solutions; high temperature etching of Ge with HI; growth rate in the Ge-I2-He-H2 vapor transport system; exitaxial Ge growth in the Ge-C12-H2 system; Bourdon gauge measurements on the ...

A. Reisman

1964-01-01

328

Monolithic Microwave Integrated Circuit Water Vapor Radiometer.  

National Technical Information Service (NTIS)

A proof of concept Monolithic Microwave Integrated Circuit (MMIC) Water Vapor Radiometer (WVR) is under development at the Jet Propulsion Laboratory (JPL). WVR's are used to remotely sense water vapor and cloud liquid water in the atmosphere and are valua...

L. M. Sukamto T. W. Cooley M. A. Janssen G. S. Parks

1991-01-01

329

Chemical Vapor Deposition of Thin Film Dielectrics.  

National Technical Information Service (NTIS)

Chemical vapor deposition (CVD) utilizing the reaction of tetraisopropyl titanate in an oxidizing atmosphere containing water vapor forms a thin film of TiO2 with the desirable dielectric properties. CVD yields the widest range of technological possibilit...

D. R. Harbison H. L. Taylor

1968-01-01

330

Vapor Pressure of Methylphosphonic Dichloride: A Compendium.  

National Technical Information Service (NTIS)

Vapor-pressure data for methylphosphonic dichloride from many sources are reviewed and analyzed to obtain a best-fit predictive Antoine equation. Also given are the heat of vaporization and volatility at various temperatures. Zeffert published an Antoine ...

A. Brozena D. Fielder

1985-01-01

331

Studies of Oscillatory Combustion and Fuel Vaporization.  

National Technical Information Service (NTIS)

Research projects involving oscillatory combustion and fuel vaporization are reported. Comparisons of experimental and theoretical droplet vaporization histories under ambient conditions such that the droplet may approach its thermodynamic critical point ...

G. L. Borman O. A. Uyehara P. S. Myers

1972-01-01

332

Application of oil vaporization evaluation methods.  

National Technical Information Service (NTIS)

This paper describes and quantifies the benefits of residual oil vaporization in an enhanced recovery gas injection project. Vaporized oil is recovered as natural gas liquid (NGL) when the injected gas is produced. In the reservoir application studied, 20...

W. W. Fleckenstein L. S. Bouck D. Hudgens M. Querin L. Williams

1992-01-01

333

Automated Test Systems for Toxic Vapor Detectors.  

National Technical Information Service (NTIS)

The NASA Toxic Vapor Detection Laboratory (TVDL) at the Kennedy Space Center (KSC), Florida, has been using Personal Computer based Data Acquisition and Control Systems (PCDAS) for about nine years. These systems control the generation of toxic vapors of ...

C. B. Mattson T. A. Hammond C. J. Schwindt

1997-01-01

334

Atomic vapor laser isotope separation process  

DOEpatents

A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

Wyeth, R.W.; Paisner, J.A.; Story, T.

1990-08-21

335

Heavy gas releases: recent dispersion research  

Microsoft Academic Search

The important liquefied fuels which form heavy gases are liquefied natural gas (LNG) (comprised chiefly of methane, but with small amounts of propane and ethane), and liquefied petroleum gas (LPG), (comprised of propane and butane in various ratios). In addition to other fuels with these properties, there are a variety of industrial gases transported in pressurized vessels, such as hydrocarbons

J. H. Shinn; D. L. Ermak; R. P. Koopman

1981-01-01

336

Turbulent dispersal promotes species coexistence  

PubMed Central

Several recent advances in coexistence theory emphasize the importance of space and dispersal, but focus on average dispersal rates and require spatial heterogeneity, spatio-temporal variability or dispersal-competition tradeoffs to allow coexistence. We analyse a model with stochastic juvenile dispersal (driven by turbulent flow in the coastal ocean) and show that a low-productivity species can coexist with a high-productivity species by having dispersal patterns sufficiently uncorrelated from those of its competitor, even though, on average, dispersal statistics are identical and subsequent demography and competition is spatially homogeneous. This produces a spatial storage effect, with an ephemeral partitioning of a ‘spatial niche’, and is the first demonstration of a physical mechanism for a pure spatiotemporal environmental response. ‘Turbulent coexistence’ is widely applicable to marine species with pelagic larval dispersal and relatively sessile adult life stages (and perhaps some wind-dispersed species) and complements other spatial and temporal storage effects previously documented for such species.

Berkley, Heather A; Kendall, Bruce E; Mitarai, Satoshi; Siegel, David A

2010-01-01

337

New Optical Rotation Dispersion Formula.  

National Technical Information Service (NTIS)

A new dispersion formula for the rotatory power is obtained in the framework of Kubo formalism for transport coefficients. Unlike the well known Rosenfeld-Condon dispersion law, this formula is consistent with the free electron gas asymptotic behavior. (A...

I. Kimel

1981-01-01

338

IMPROVED LABORATORY DISPERSANT EFFECTIVENESS TEST  

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) initiated a program to evaluate an Improved Laboratory Dispersant Effectiveness Test (ILDET) which was developed to replace EPA's Revised Standard Dispersant Effectiveness Test (RSDET). The report summarizes the development of the IL...

339

Droplet velocity dispersion device  

NASA Astrophysics Data System (ADS)

A droplet velocity dispersion device (DVDD), which can measure the uniformity of a droplet stream injected into a high vacuum, was developed. Droplet streams are passed through light; a magnified shadow image is reflected to the detector; and the stream image is superimposed on a slit which is perpendicular to the stream. The DVDD converts each image to signals which represent the shape, size, and longitudinal spacing of the droplet stream. The instrument can measure velocity dispersion to an accuracy of one part in 10 to the 6th. In order to obtain an accurate representation of the droplet stream, the time response of the DVDD must be small; in addition, the slit width of the detector has to be the correct size to admit the proper light level. These parameters were determined and the device tested. The test results compare well with theory. The information obtained from the DVDD can be used to develop a liquid droplet radiator for space application.

Dixon, M.

340

Dispersed Rayleigh interferometer  

NASA Astrophysics Data System (ADS)

In order to further improve the performance of Rayleigh Interferometer (RI) used for measurement of gas/liquid index, a Dispersed Rayleigh Interferometer (DRI), which uses a broadband source and disperses monochromatic interference pattern perpendicular to the direction of baseline, is proposed to expand measurement range and to acquire optical path difference dynamically by only one frame of interference pattern. At the same time, an algorithm used to analyse the interference pattern automatically is proposed. A DRI which uses a pair of transmissive phase plates used for generating optical path difference has been built up. The measurement range reaches 200?m, measurement error is less than 20nm and repeatability is better than 2nm in whole range. Good performance of DRI makes itself to be a suitable approach not only used in the conventional measurement of gas/quid index, but also in other aspects, for example, co-phasing of segmented mirrors for large telescopes.

Wang, Shanshan; Zhu, Qiudong; Cao, Genrui

2009-05-01

341

CPMG Relaxation Dispersion.  

PubMed

NMR relaxation is sensitive to molecular and internal motion of proteins. (15)N longitudinal relaxation rate (R 1), transverse relaxation rate (R 2), and {(1)H}-(15)N Nuclear Overhauser Effect (NOE) experiments are often performed to globally elucidate protein dynamics, primarily on the sub-nanosecond timescale. In contrast, constant relaxation time R 2 dispersion experiments are applied to characterize protein equilibrium conformations that interconvert on the millisecond timescale. Information on local conformational equilibria of proteins provides important insights about protein energy landscapes and is useful to interpret molecular recognition mechanisms as well. Here, we describe a protocol for performing (15)N Carr-Purcell-Meiboom-Gill (CPMG) R 2 dispersion measurements in solution, including protein preparation, step-by-step experimental parameter settings, and the first step of data analysis. PMID:24061914

Ishima, Rieko

2014-01-01

342

Coal-water dispersion  

SciTech Connect

A dispersion is described comprising water, pulverized coal and stabilizing additives, the coal content ranging from 60 to 80% by weight and the additives comprising a combination of (a) sufficient lecithin adsorbed on surfaces of coal particles to provide repulsion between the coal particles by hydration forces and (b) polymer cooperating with the lecithin and comprising at least one polymer having segments of hydrophobic as well as segments of hydrophilic character.

Stigsson, L.L.; Lindman, B.

1986-07-08

343

Cold plasma dispersion surfaces  

Microsoft Academic Search

Following the work of Stringer (1963), this study presents three-dimensional plots of dispersion in a cold anisotropic plasma. The omega(k, theta) surfaces (where k is the wave vector for a fixed angle of propagation) provide a clear picture of the behavior of cold plasma waves as the direction of propagation is varied. The group velocity (dw\\/dk) has a simple geometrical

M. E. Oakes; R. B. Michie; K. H. Tsui; J. E. Copeland

1979-01-01

344

Disabling Radiological Dispersal Terror  

SciTech Connect

Terror resulting from the use of a radiological dispersal device (RDD) relies upon an individual's lack of knowledge and understanding regarding its significance. Disabling this terror will depend upon realistic reviews of the current conservative radiation protection regulatory standards. It will also depend upon individuals being able to make their own informed decisions merging perceived risks with reality. Preparation in these areas will reduce the effectiveness of the RDD and may even reduce the possibility of its use.

Hart, M

2002-11-08

345

Rheology of scleroglucan dispersions  

Microsoft Academic Search

The rheological properties of a scleroglucan, industrially produced by Sclerotium rolfsii, either in aqueous or dimethylsulfoxide (DMSO) dispersions at concentrations (c) ranging from 0.01% to 1.5% (w\\/w) were determined by using Cannon–Fenske capillary viscometers and a dynamic stress rheometer with plate-and-cone geometry under steady shear flow, small amplitude oscillatory shear and creep. The intrinsic viscosity [?] in water and DMSO

Mauro Moresi; Stefano Lo Presti; Marco Mancini

2001-01-01

346

Nozzle for electric dispersion reactor  

DOEpatents

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 5 figs.

Sisson, W.G.; Harris, M.T.; Scott, T.C.; Basaran, O.A.

1998-06-02

347

Nozzle for electric dispersion reactor  

DOEpatents

A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Sisson, Warren G. (Oak Ridge, TN); Basaran, Osman A. (Oak Ridge, TN); Harris, Michael T. (Knoxville, TN)

1998-01-01

348

Nozzle for electric dispersion reactor  

DOEpatents

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Sisson, Warren G. (Oak Ridge, TN); Harris, Michael T. (Knoxville, TN); Scott, Timothy C. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN)

1998-01-01

349

Nozzle for electric dispersion reactor  

DOEpatents

A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Sisson, Warren G. (Oak Ridge, TN); Basaran, Osman A. (Oak Ridge, TN); Harris, Michael T. (Knoxville, TN)

1995-01-01

350

Nozzle for electric dispersion reactor  

DOEpatents

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Sisson, Warren G. (Oak Ridge, TN); Harris, Michael T. (Knoxville, TN); Scott, Timothy C. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN)

1996-01-01

351

Nozzle for electric dispersion reactor  

DOEpatents

A nozzle for an electric dispersion reactor includes two coaxial cylindrical bodies, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 5 figs.

Sisson, W.G.; Harris, M.T.; Scott, T.C.; Basaran, O.A.

1996-04-02

352

Meals, quarters for 8,200 needed at peak in LNG project  

SciTech Connect

It has everything a real town has except women, children, schools, bars, and old people. It is the huge camp built at Ras Laffan, Qatar, on the shores of the Persian Gulf to lodge and feed over 5,000 workers as they build the first plant in the emirate for liquefying millions of tons of natural gas yearly. Japan`s Chiyoda Corp. is the top contractor for the Qatar Liquefied Gas Co. (QatarGas) project, which is owned by a Qatari, French, American, and Japanese consortium. As part of the plant construction contract, Chiyoda built the camp, which Teyseer Services Co., the Qatar affiliate of the French company, Sodexho Alliance, now runs and maintains. Sodexho is the world`s largest catering/remote site management organization. It has had all its expertise in those fields put to the test for nearly 4 years supporting this world-scale LNG project which will be completed this summer. This project is described.

Aalund, L.R.

1998-04-27

353

A discharge heated copper vapor laser  

Microsoft Academic Search

A simple, reliable copper vapor laser is described with vapor produced by discharge heating. Average output power of 1.3 W has resulted at 6.8 kHz and a specific energy of 39 ?J\\/cm3. Copper vapor density as high as3 times 10^{16}cm-3was achieved.

R. S. Anderson; L. Springer; B. G. Bricks; T. W. Karras

1975-01-01

354

Nuclear vapor thermal reactor propulsion technology  

Microsoft Academic Search

The conceptual design of a nuclear rocket based on the vapor core reactor is presented. The Nuclear Vapor Thermal Rocket (NVTR) offers the potential for a specific impulse of 1000 to 1200 s at thrust-to-weight ratios of 1 to 2. The design is based on NERVA geometry and systems with the solid fuel replaced by uranium tetrafluoride (UF4) vapor. The

Isaac Maya; Nils J. Diaz; Edward T. Dugan; Yoichi Watanabe; James A. McClanahan; Wen-Hsiung Tu; Robert L. Carman

1993-01-01

355

Far-field dispersal modeling for fuel-air-explosive devices  

SciTech Connect

A computer model for simulating the explosive dispersal of a fuel agent in the far-field regime is described and is applied to a wide variety of initial conditions to judge their effect upon the resulting fuel/air cloud. This work was directed toward modeling the dispersal process associated with Fuel-Air-Explosives devices. The far-field dispersal regime is taken to be that time after the initial burster charge detonation in which the shock forces no longer dominate the flow field and initial canister and fuel mass breakup has occurred. The model was applied to a low vapor pressure fuel, a high vapor pressure fuel and a solid fuel. A strong dependence of the final cloud characteristics upon the initial droplet size distribution was demonstrated. The predicted fuel-air clouds were highly non-uniform in concentration. 18 refs., 86 figs., 4 tabs.

Glass, M.W.

1990-05-01

356

Modeling dispersion in optical fibers: applications to dispersion tailoring and dispersion compensation  

Microsoft Academic Search

The phenomenon of temporal pulse dispersion, which is a key characteristic of an optical fiber communication system is described\\u000a from the first principles. Beginning with the basics of dispersion in a bulk medium, these concepts are then applied to propagation\\u000a of a pulse in an optical fiber. Details of modeling dispersion are then described in the context of dispersion tailoring

K. Thyagarajan; B. P. Pal

357

Modeling dispersion in optical fibers: applications to dispersion tailoring and dispersion compensation  

Microsoft Academic Search

The phenomenon of temporal pulse dispersion, which is a key characteristic of an optical fiber communication system is described\\u000a from the first principles. Beginning with the basics of dispersion in a bulk medium, these concepts are then applied to propagation\\u000a of a pulse in an optical fiber. Details of modeling dispersion are then described in the context of dispersion tailoring

K. Thyagarajan; B. P. Pal

2007-01-01

358

Vapor-liquid equilibrium of a multipolar square-well fluid II. Effect of a variable square-well range  

Microsoft Academic Search

The multipolar square-well (MSW) fluid treated in part I [Physica A 202 (1994) 420] is studied in order to analyze the effect of SW range ?, which models the range of dispersion forces, on the vapor-liquid (VL) equilibrium. The model includes a simpler and more accurate treatment of the SW interactions of variable width. The MSW model covers systems ranging

Fernando del Río; Ana Laura Benavides; Yolanda Guevara

1995-01-01

359

Measurements of vaporized and liquid fuel concentration fields in a burning spray jet of acetone using planar laser induced fluorescence  

Microsoft Academic Search

Planar LIF of acetone has been performed in the near development field of a burning spray jet. The main difficulty of such investigations comes from the large range of signal levels provided by the vapor and the size dispersed spray, which cannot be covered by the camera dynamics. The key point of the present work lies in a strong compression

R. Bazile; D. Stepowski

1995-01-01

360

Fluidized Bed Chemical Vapor Deposition Synthesis of Carbon Nanotubes Using Different Fe–Co\\/Alumina Catalytic Powders  

Microsoft Academic Search

Catalytic particles, Iron-Cobalt supported on Alumina, with different metal compositions were investigated in fluidized bed chemical vapor deposition of Ethanol at 600°C to produce carbon nanotubes (CNTs). The characteristics of catalytic particles as well as product were studied using different analytical techniques. Results indicated that the dispersion of metallic nanoparticles was higher when small amounts of two kinds of metal

A. Fakhrul-Razi; F. Danafar; A. B. Dayang Radiah; M. S. Mohd Amran

2012-01-01

361

Vapor deposition of tantalum and tantalum compounds  

SciTech Connect

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

Trkula, M. [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

1996-04-01

362

Mechanical vapor recompression for waste energy recovery  

SciTech Connect

This paper is concerned with energy recovery in petroleum distillation processes utilizing mechanical vapor recompression. Several examples illustrating recompression of head vapors for heating the reboiler of a distillation tower are presented. The advantages of the mechanical vapor recompression system using a screw compressor are discussed in detail. The system is economically attractive with simple payback periods often less than two years. The paper describes the merits of mechanical vapor recompression, using a screw-type compressor for recovering energy at the distillation tower, and how it can be accomplished by using an intermediary fluid such as steam or by recompressing the distillation column vapors directly.

Becker, F.E.; Zakak, A.I.

1985-03-01

363

Vapor intrusion from entrapped NAPL sources and groundwater plumes  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOC) are commonly found entrapped as non-aqueous phase liquids (NAPLs) in the soil pores or dissolved in groundwater at industrial waste sites and refineries. Vapors emitted from these contaminant sources readily disperse into the atmosphere, into air-filled void spaces within the soil, and migrate below surface structures, leading to the intrusion of contaminant vapors into indoor air through basements and other underground structures. This process referred to as vapor intrusion (VI) represents a potential threat to human health, and is a possible exposure pathway of concern to regulatory agencies. To assess whether this exposure pathway is present, remediation project managers often rely in part on highly simplified screening level models that do not take into consideration the complex flow dynamics controlled by subsurface heterogeneities and soil moisture conditions affected by the mass and heat flux boundary conditions at the land/atmospheric interface. A research study is under way to obtain an improved understanding of the processes and mechanisms controlling vapor generation from entrapped NAPL sources and groundwater plumes, their subsequent migration through the subsurface, and their attenuation in naturally heterogeneous vadose zones under various natural physical, climatic, and geochemical conditions. Experiments conducted at multiple scales will be integrated with analytical and numerical modeling and field data to test and validate existing VI theories and models. A set of preliminary experiments where the fundamental process of vapor generation from entrapped NAPL sources and dissolved plumes under fluctuating water were investigated in small cells and two-dimensional test tanks. In another task, intermediate scale experiments were conducted to generate quantitative data on how the heat and mass flux boundary conditions control the development of dynamic VI pathways. The data from the small cell and tank experiments were used to test whether the equilibrium mass transfer assumption is valid under normal pressure gradients generated from atmospheric pressure variations and fluctuations of pressure in the building. The data from the intermediate scale airflow experiments were used to validate a numerical models based on a multi-physics simulator. These analyses will help us to evaluate the significance of the boundary conditions at the land/ atmospheric interface on the development of dynamic air pathways that transmit vapors from contaminant sources to buildings. The experimental findings and models are used to design a set of experiments in a coupled wind tunnel/ porous media test facility where integrated models of atmospheric and shallow subsurface interaction and up-scaling theories will be tested and validated.

Illangasekare, Tissa H.; Sakaki, Toshihiro; Christ, John; Petri, Bejamin; Sauck, Carolyn; Cihan, Abdullah

2010-05-01

364

Dispersal range analysis: quantifying individual variation in dispersal behaviour.  

PubMed

A complete understanding of animal dispersal requires knowledge not only of its consequences at population and community levels, but also of the behavioural decisions made by dispersing individuals. Recent theoretical work has emphasised the importance of this dispersal process, particularly the phase in which individuals search the landscape for breeding opportunities. However, empirical advances are currently hampered by a lack of tools for quantifying these dispersal search tactics. Here, we review existing methods for quantifying movement that are appropriate for the dispersal search process, describe several new techniques that we developed for characterising movement and behaviour through an individual's dispersal range, and illustrate their use with data from Australasian treecreepers (Climacteridae). We also describe how the quantitative parameters we discuss are calculated in a freely available computer software package that we designed. Specifically, we present methods for calculating the area searched during dispersal, search rate, thoroughness, intensity, philopatry of search, timing of exploration, and surreptitiousness. When we applied this approach to the study of dispersal in treecreepers, we found that search area, philopatry and timing of exploration showed the greatest individual variation. Furthermore, search area, search rate, thoroughness and philopatry of search were all correlated, suggesting they may be useful parameters for further research on the causes and consequences of different dispersal search tactics. Finally, we make recommendations for modifying radiotracking protocols to facilitate more accurate assessment of individual variation in the dispersal process, and suggest future directions for this type of empirical work at the interface of population and behavioural ecology. PMID:15378345

Doerr, Erik D; Doerr, Veronica A J

2004-09-17

365

Application of waste heat powered absorption refrigeration system to the LNG recovery process  

Microsoft Academic Search

The recovery process of the liquefied natural gas requires low temperature cooling, which is typically provided by the vapor compression refrigeration systems. The usage of an absorption refrigeration system powered by waste heat from the electric power generating gas turbine could provide the necessary cooling at reduced overall energy consumption. In this study, a potential replacement of propane chillers with

Paul Kalinowski; Yunho Hwang; Reinhard Radermacher; Saleh Al Hashimi; Peter Rodgers

2009-01-01

366

Apparatus for physical vapor deposition  

US Patent & Trademark Office Database

An apparatus for physical vapor deposition comprising a vacuum casing one end of which is open; a sealing member provided at the opening of the casing; an electrode for physical vapor deposition, such as a target electrode or an electrode for heating evaporation, which is provided in the casing; and an exhaust hole for exhausting gases in the casing, which is provided at a predetermined wall portion of the casing. The apparatus may also be provided with a gas introducing hole and a bias electrode. The casing is integrally fitted to a body to be treated at the opening end portion thereof by means of the sealing member to form a vacuum chamber therein. This apparatus is compact and enables the surface treatment of a large or immovable body without moving the body.

Shimada; Hisashi (Nagoya, JP); Arai; Tohru (Toyoake, JP); Endo; Junji (Nagoya, JP)

1985-04-30

367

CC Cryostat Vapor Pressure Thermometers  

SciTech Connect

Vapor pressure thermometers will be used to measure the temperature or the liquid argon in the cryostat at two different levels. One bulb will be positioned near the top of the vessel, and a second bulb will be located near the bottom of the vessel. The volume of the bulbs is dependent upon the charge temperature and pressure chosen, the temperature range of the thermometer desired, the size and length of tubing used, and the warm volume involved.

Kurita, C.H.; /Fermilab

1987-10-01

368

Vapor phase lubrication of ceramics  

SciTech Connect

Vapor phase lubrication of ceramics under sliding wear has been extended up to 500{degrees}C, using tricresyl phosphate as the vaporized lubricant. In order to successfully lubricate ceramics, it was necessary to first activate the surface with a metal. Different methods of activating the surface have been investigated, including in-situ reaction with metal components. Continuous vapor phase lubrication of the activated ceramic reduced the coefficient of friction from 0.7 to less than 0.1, resulting in essentially no wear. The reduction in the wear rate and friction coefficient was due to a polymeric derivative of the original TCP which was formed on the high temperature surfaces. The deposit formed on the surface was analyzed using high performance liquid chromotography (HPLC). Results have suggested that it ins an organic polymer with a molecular range of 6000 to 60000 gmole/mole and an average molecular weight of approximately 30000 gmole/mole. This method of lubrication has direct application for the continuous lubrication of ceramic engines. 9 refs., 12 figs., 1 tab.

Hanyaloglu, B.; Graham, E.E. [Cleveland State Univ., OH (United States)

1994-10-01

369

Acoustic Droplet Vaporization through PDMS  

NASA Astrophysics Data System (ADS)

Acoustic droplet vaporization (ADV) involves the generation of bubbles from albumin-encapsulated perfluorocarbon (PFC) droplets that have been insonated with high intensity ultrasound (US). Gas embolotherapy, utilizing ADV, may facilitate occlusion of blood flow in the vasculature as bubbles undergo volume expansion of up to 125 times. Cancer therapy could benefit from such occlusions through starvation of the tumor. In order to visualize the detailed mechanics of vaporization and expansion process of the PFC droplets, idealized microvessels were constructed using polydimethylsiloxane (PDMS) channels. Microchannels (20 micron diameter) were fabricated using PDMS with polymer-crosslinker mixing ratios ranging from 5:1 to 20:1. Droplets were introduced into the channels and exposed to US for vaporization. Mixing ratios were observed to impact the impedance matching at the water-PDMS interface, which affected the threshold for ADV. The threshold was lowest for mixing ratios of 5:1 and 20:1, and greatest for 9:1. Final bubble volumes were compared with a computational model by Ye & Bull and were found to be consistent. This work is supported by NIH grant R01EB006476.

Li, David; Samuel, Stanley; Fowlkes, J. Brian; Bull, Joseph

2009-11-01

370

Dispersion toughened ceramic composites and method for making same  

DOEpatents

Ceramic composites exhibiting increased fracture toughness are produced by the simultaneous codeposition of silicon carbide and titanium disilicide by chemical vapor deposition. A mixture of hydrogen, methyltrichlorosilane and titanium tetrachloride is introduced into a furnace containing a substrate such as graphite or silicon carbide. The thermal decomposition of the methyltrichlorosilane provides a silicon carbide matrix phase and the decomposition of the titanium tetrachloride provides a uniformly dispersed second phase of the intermetallic titanium disilicide within the matrix phase. The fracture toughness of the ceramic composite is in the range of about 6.5 to 7.0 MPa..sqrt..m which represents a significant increase over that of silicon carbide.

Stinton, D.P.; Lackey, W.J.; Lauf, R.J.

1984-09-28

371

Dispersion toughened ceramic composites and method for making same  

DOEpatents

Ceramic composites exhibiting increased fracture toughness are produced by the simultaneous codeposition of silicon carbide and titanium disilicide by chemical vapor deposition. A mixture of hydrogen, methyltrichlorosilane and titanium tetrachloride is introduced into a furnace containing a substrate such as graphite or silicon carbide. The thermal decomposition of the methyltrichlorosilane provides a silicon carbide matrix phase and the decomposition of the titanium tetrachloride provides a uniformly dispersed second phase of the intermetallic titanium disilicide within the matrix phase. The fracture toughness of the ceramic composite is in the range of about 6.5 to 7.0 MPa.sqroot.m which represents a significant increase over that of silicon carbide.

Stinton, David P. (Knoxville, TN); Lackey, Walter J. (Oak Ridge, TN); Lauf, Robert J. (Oak Ridge, TN)

1986-01-01

372

Dispersed and periodic microstructures for magnetic and infrared absorbers  

NASA Astrophysics Data System (ADS)

This is the final report on a study of the electromagnetic characteristics of model materials having a finely divided ferromagnetic phase in a nonmetallic matrix. The overall objective of the work was to achieve a theoretical understanding of the physics of microwave and infrared absorption in these materials, but because of lack of funds only fabrication and microstructure and electromagnetic characterization of one material combination made by one process was completed, although a theoretical framework for analytical modeling of the materials was laid out. The process used to fabricate model specimens that were studied was chemical vapor co-deposition, and the material combination studied was a dispersion of cobalt particles in carbon.

Kaae, J. L.; Duggan, D. W.

1989-03-01

373

Mechanical and physical properties of epoxy composites reinforced by vapor grown carbon nanofibers  

Microsoft Academic Search

Epoxy\\/vapor grown carbon nanofiber composites (VGCF) with different proportions of VGCF were fabricated by the in situ process.The VGCFs were well dispersed in both of the low and high viscosity epoxy matrices, although occasional small aggregates were observed in a high viscosity epoxy of 20wt.%. The dynamic mechanical behavior of the nanocomposite sheets was studied. The storage modulus and the

Young-Kuk Choi; Koh-ichi Sugimoto; Sung-Moo Song; Yasuo Gotoh; Yutaka Ohkoshi; Morinobu Endo

2005-01-01

374

Chiroptical Spectroscopy in the Vapor Phase  

NASA Astrophysics Data System (ADS)

Electromagnetic radiation propagating through an isotropic chiral medium experiences a complex index of refraction that differs in both real (in-phase) and imaginary (in-quadrature) parts for the right-circular and left-circular polarization states that define the helicity basis. The resulting phenomena of circular birefringence (CB) and circular dichroism (CD) lead to observable effects in the form of dispersive rotation and absorptive elliptization for an impinging beam of plane-polarized light, which commonly are measured under conditions of nonresonant and resonant excitation, respectively. This talk will discuss ongoing efforts designed to elucidate the provenance of electronic optical activity under complementary solvated and isolated conditions, with the latter vapor-phase work made possible by our continuing development of Cavity Ring-Down Polarimetry (CRDP). Molecules of interest include the rigid bicyclic ketone (1R,4R)-norbornenone, where the spatial arrangement of distal alkene and carbonyl moeities gives rise to extraordinarily large specific rotation (CB) parameters that are predicted incongruously by different quantum-chemical methods; the monoterpene constitutional isomers (S)-2-carene and (S)-3-carene, which display surprisingly distinct chiroptical properties; and conjugated ketones such as (S)-verbenone, where CD probes of weak ?*?n absorption bands have been performed at vibronic resolution. The disparate nature of gas-phase and condensed-phase optical activity will be highlighted, with complementary ab initio calculations serving to elucidate the structural, chemical, and electronic origins of observed behavior. T. Müller, K. B. Wiberg, P. H. Vaccaro, J. R. Cheeseman, and M. J. Frisch, J. Opt. Soc. Am. B 19, 125 (2002) P. H. Vaccaro, ``Chapter 1.II.10: Optical Rotation and Intrinsic Optical Activity'' in Comprehensive Chiroptical Spectroscopy, N. Berova, P. L. Polavarapu, K. Nakanishi, and R. W. Woody, eds. (John Wiley and Sons, Inc., Hoboken, NJ, 2011).

Lahiri, Priyanka; Long, Benjamin D.; Wiberg, Kenneth B.; Vaccaro, Patrick H.

2011-06-01

375

ACOUSTIC RECTIFICATION IN DISPERSIVE MEDIA  

SciTech Connect

It is shown that the shapes of acoustic radiation-induced static strain and displacement pulses (rectified acoustic pulses) are defined locally by the energy density of the generating waveform. Dispersive properties are introduced analytically by assuming that the rectified pulses are functionally dependent on a phase factor that includes both dispersive and nonlinear terms. The dispersion causes an evolutionary change in the shape of the energy density profile that leads to the generation of solitons experimentally observed in fused silica.

Cantrell, John H. [NASA Langley Research Center, Mail Stop 231, Hampton, VA 23681 (United States)

2009-03-03

376

40 CFR Appendix C to Part 300 - Swirling Flask Dispersant Effectiveness Test, Revised Standard Dispersant Toxicity Test, and...  

Code of Federal Regulations, 2010 CFR

... EFFD =EFFd âEFFc (5) where: EFFD =% dispersed oil due to dispersant only EFFd =% dispersed oil with dispersant added EFFc = % dispersed oil with no dispersant added 20. Calculate the average dispersant...

2009-07-01

377

40 CFR Appendix C to Part 300 - Swirling Flask Dispersant Effectiveness Test, Revised Standard Dispersant Toxicity Test, and...  

Code of Federal Regulations, 2010 CFR

... EFFD =EFFd âEFFc (5) where: EFFD =% dispersed oil due to dispersant only EFFd =% dispersed oil with dispersant added EFFc = % dispersed oil with no dispersant added 20. Calculate the average dispersant...

2010-07-01

378

Polymer Solutions and Dispersions  

NSDL National Science Digital Library

So far, we have spent a considerable amount of time discussing the strength of polymers and their unique physical and mechanical properties. However, some applications take excellent advantage of the interesting properties polymers bring to solutions. Examples include paints, motor oils, and some of the products we put on our hair. In addition, as we saw in the last chapter, some polymers are synthesized in solution. In this chapter, we will present some of the important properties of polymer solutions and develop a basic understanding of their origin. Some polymers would "like" to dissolve but can't. We'll try to understand why, and see how to take advantage of this. And, finally, we'll investigate some uses for polymers that are not actually dissolved in a solvent but rather are dispersed in a liquid.

Teegarden, David

2004-01-01

379

Geometry of physical dispersion relations  

SciTech Connect

To serve as a dispersion relation, a cotangent bundle function must satisfy three simple algebraic properties. These conditions are derived from the inescapable physical requirements that local matter field dynamics must be predictive and allow for an observer-independent notion of positive energy. Possible modifications of the standard relativistic dispersion relation are thereby severely restricted. For instance, the dispersion relations associated with popular deformations of Maxwell theory by Gambini-Pullin or Myers-Pospelov are not admissible. Dispersion relations passing the simple algebraic checks derived here correspond to physically admissible Finslerian refinements of Lorentzian geometry.

Raetzel, Dennis; Rivera, Sergio; Schuller, Frederic P. [Albert Einstein Institute, Max Planck Institute for Gravitational Physics, Am Muehlenberg 1, 14476 Golm (Germany)

2011-02-15

380

Longitudinal dispersion control for the Keck interferometer nuller  

NASA Astrophysics Data System (ADS)

The control of longitudinal dispersion, which determines the position of the null fringe as a function of wavelength, is central to the problem of producing deep broadband interferometric nulls. The dispersion is the sum of terms due to environmental factors such as the dry-air and water-vapor atmospheric seeing, the unbalanced air column due to the unequal delay-line paths between the telescopes the combiner, and to the distance from the central fringe. The difference between an achromatic nuller and a normal constructive combiner operating at its first (chromatic) null can be thought of as an added longitudinal dispersion, which for the case of the Keck Interferometer is smaller than the environmental terms. We demonstrate that the sum of these effects can be adequately compensated by an appropriate thickness of ZnSe combined with an additional achromatic pathlength. The Keck Interferometer nulling combiners take advantage of this result. They are intrinsically constructive combiners made to produce achromatic nulls by inserting a ZnSe dispersion corrector into each of the four input beams. We describe the null fringe stabilization control algorithm and present calculations of the required loop bandwidth and precision. A potentially important advantage of the present approach is that the system will be able to function as either a destructive or constructive combiner, depending on the value of a single control-loop parameter (the target fringe phase).

Koresko, Christopher D.; Mennesson, Bertrand P.; Serabyn, Eugene; Colavita, Mark; Akeson, Rachel L.; Swain, Mark R.

2003-02-01

381

Biofilter treatment of ethanol vapors  

SciTech Connect

Bench scale experiments and a numerical model were used to test the effectiveness of biofiltration in treating air contaminated with ethanol vapors. Three packing materials, granular activated carbon, compost, and a mixture of compost and diatomaceous earth were tested. The GAC material supported the highest elimination rates, ranging from 53 to 219 grams/m[sup 3]-hr for a range of loading rates. Partitioning coefficients for the contaminant on the biofilter packing material had a strong effect on the efficiency of the biofilters. 10 refs., 12 figs.

Hodge, D.S. (Reynolds Group, Tustin, CA (United States)); Devinny, J.S. (Univ. of Southern California, Los Angeles, CA (United States))

1994-08-01

382

Microwave assisted chemical vapor infiltration  

SciTech Connect

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

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

1991-12-31

383

Microwave assisted chemical vapor infiltration  

SciTech Connect

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

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

1991-01-01

384

Chemical vapor deposition of sialon  

DOEpatents

A laminated composite and a method for forming the composite by chemical vapor deposition. The composite includes a layer of sialon and a material to which the layer is bonded. The method includes the steps of exposing a surface of the material to an ammonia containing atmosphere; heating the surface to at least about 1200.degree. C.; and impinging a gas containing in a flowing atmosphere of air N.sub.2, SiCl.sub.4, and AlCl.sub.3 on the surface.

Landingham, Richard L. (Livermore, CA); Casey, Alton W. (Livermore, CA)

1982-01-01

385

Overview of chemical vapor infiltration  

SciTech Connect

Chemical vapor infiltration (CVI) is developing into a commercially important method for the fabrication of continuous filament ceramic composites. Current efforts are focused on the development of an improved understanding of the various processes in CVI and its modeling. New approaches to CVI are being explored, including pressure pulse infiltration and microwave heating. Material development is also proceeding with emphasis on improving the oxidation resistance of the interfacial layer between the fiber and matrix. This paper briefly reviews these subjects, indicating the current state of the science and technology.

Besmann, T.M.; Stinton, D.P.; Lowden, R.A.

1993-06-01

386

CO2 DIAL measurements of water vapor  

Microsoft Academic Search

CO2 lidars have heretofore been used to measure water vapor concentrations primarily using the 10R(20) line at 10.247 microns, which has a strong overlap with a water vapor absorption line. This paper discusses the use of that line as well as other CO2 laser lines for which the absorption coefficients are weaker. The literature on measurement of water vapor absorption

William B. Grant; Jack S. Margolis; Alan M. Brothers; David M. Tratt

1987-01-01

387

Recover heat by mechanical vapor recompression  

SciTech Connect

Several examples illustrating recompression of head vapors for heating the reboiler of a distillation tower are presented. The advantages of the mechanical vapor recompression system using a screw compressor are discussed in detail. The system is economically attractive with simple payback periods often less than two years. Numerous studies have identified a number of alternatives for lowering energy consumption in the distillation process through various heat recovery techniques. One such technique utilizes mechanical vapor recompression. By mechanically recompressing low-pressure vapors, a better match can be made between low-grade waste energy sources and process uses, thereby improving plant energy efficiency.

Becker, F.E.; Zakak, A.I.

1985-05-01

388

Synthesis of silicon carbide nanotubes by chemical vapor deposition.  

PubMed

Silicon carbide nanotubes (SiCNTs) were directly synthesized by chemical vapor deposition (CVD) in the paper. Methyltrichlorosilane (MTS) was selected as the SiC gaseous source and, ferrocence and thiophene as the catalyst and the cocatalyst, respectively. The influences of reaction temperature, contents of catalyst and cocatalyst, and content of gaseous source on the morphologies of the products were investigated, respectively. The products were identified by high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray (EDX), respectively. The synthesis of SiCNTs by CVD suggested a condition-dependent process. Novel SiCNTs, with 20 approximately 80 nm in outer diameter and 15 approximately 35 nm in inner diameter, respectively, were observed. The wall structure similar to that of carbon nanotubes was not found for the SiCNTs. PMID:17450808

Xie, Zhengfang; Tao, Deliang; Wang, Jiqing

2007-02-01

389

Prevalence and association of the longus pilus structural gene (lngA) with colonization factor antigens, enterotoxin types, and serotypes of enterotoxigenic Escherichia coli.  

PubMed Central

Human enterotoxigenic Escherichia coli (ETEC) produces a plasmid-encoded type IV pilus termed longus (for long pilus). Regardless of the geographic origins of ETEC strains, the longus structural gene lngA was found to have the highest level of association with ETEC producing colonization factor antigen (CFA) CFA/II, followed by ETEC producing CFA/I and CFA/IV. ETEC bearing the less prevalent CFA/III and putative colonization factors and ETEC negative for CFA and putative colonization factor also contained lngA-related sequences. lngA was found in a considerable number of ETEC serotypes and was more often associated with ETEC producing heat-stable enterotoxins than with ETEC producing both heat-labile and heat-stable enterotoxins or heat-labile enterotoxin alone. lngA was found more often in strains isolated from children with diarrhea than in strains from healthy children, suggesting an association with intestinal disease. We conclude that longus is a widely distributed antigenic determinant in ETEC that is highly associated with known plasmid-encoded virulence factors, namely, CFAs and enterotoxins. A longus-specific probe may be a helpful epidemiological tool to assist in the identification of ETEC.

Giron, J A; Viboud, G I; Sperandio, V; Gomez-Duarte, O G; Maneval, D R; Albert, M J; Levine, M M; Kaper, J B

1995-01-01

390

Venus Balloons using Water Vapor  

NASA Astrophysics Data System (ADS)

We propose an inflatable balloon using water vapor for the lifting gas, which is liquid in the transportation stage before entry into the high temperature atmosphere. The envelope of the balloon has an outer layer for gas barrier (a high-temperature resistant film) and an inner layer for liquid water keeping. In the descent stage using a parachute, water widely held just inside the balloon envelope can be quickly vaporized by a lot of heat flux from the surrounding high-temperature atmosphere owing to the large surface area of the balloon. As neither gas containers nor heat exchangers are necessary, we can construct a simple, lightweight and small size Venus balloon probe system. Tentative floating altitude is 35 km below the thick clouds in the Venusian atmosphere. Selection of balloon shape and material for balloon envelope are discussed in consideration of the Venusian environment such as high-temperature, high-pressure, and sulfuric acid. Balloon deployment and inflation sequence is numerically simulated. In case of the total floating mass of 10 kg at the altitude of 35 km, the volume and mass of the balloon is 1.5 cubic meters, and 3.5 kg, respectively. The shape of the balloon is chosen to be cylindrical with a small diameter. The mass of li fting gas can be determined as 4.3 kg and the remaining 2.2 kg becomes the payload mass. The mass of the total balloon system is also just 10 kg excluding the entry capsule.

Izutsu, N.; Yajima, N.; Honda, H.; Imamura, T.

391

Array-based vapor sensing using conductive carbon black-polymer composite thin film detectors  

NASA Astrophysics Data System (ADS)

A simple, broadly responsive detector array, based on polymer-carbon black composites that can detect, classify, and quantify various vapors and vapor mixtures is described. The individual detector elements of the array are constructed from films consisting of carbon black particles dispersed into insulating organic polymers. The carbon black provides an electrically conductive network in the films, whereas the different organic polymers are the source of chemical diversity between elements in the detector array. Swelling of the polymer upon exposure to a vapor increases the electrical resistance of the film by disrupting the conductive network of carbon black particles, thereby providing a simple means for monitoring the presence of a vapor. The dc electrical resistance change of an individual composite is shown to be consistent with the predictions of percolation theory. The differing gas-solid partition coefficients between vapor analytes for the various polymers of the detector array produce a characteristic pattern of resistance changes for each analyte. The response of these detectors is linear with variations in analyte concentration, allowing quantification as well as identification of a test analyte. This type of detector array can be used to discriminate different classes of analyte molecules (such as aromatics from alcohols) as well as those within a particular class (such as benzene from toluene and methanol from ethanol). Additionally, by using polymers with chiral subunits, enantiomerically different vapors can be discriminated. Principle component data analysis is used to identify and quantify airborne analytes and the relative compositions of simple gas mixtures. Integration of the electrical resistance signals with data analysis software has made sensing and analysis functions possible in a compact, low-power, simple vapor sensor device.

Severin, Erik Jon

392

Dispersion-induced chromatographic waves  

Microsoft Academic Search

Motivated by field and laboratory observations of unusual wave propagation, we investigate the behavior of simple model problems involving transport with competitive adsorption of H+ and a metal cation. In the absence of diffusion\\/dispersion, the model problem yields two shocks with the velocities expected from classical theory. In the presence of diffusion\\/dispersion, the solution exhibits an additional feature, a pulse

Steven L. Bryant; Clint Dawson; Cornelius J. van Duijn

2000-01-01

393

Matrix solid phase dispersion (MSPD)  

Microsoft Academic Search

A review of the many uses of matrix solid phase dispersion (MSPD) in the extraction and analysis of a variety of compounds from a range of samples is provided. Matrix solid phase dispersion (MSPD) has found particular application as a somewhat generic analytical process for the preparation, extraction and fractionation of solid, semi-solid and\\/or highly viscous biological samples. Its simplicity

Steven A. Barker

2007-01-01

394

Multiple overseas dispersal in amphibians  

Microsoft Academic Search

Amphibians are thought to be unable to disperse over ocean barriers because they do not tolerate the osmotic stress of salt water. Their distribution patterns have therefore generally been explained by vicari- ance biogeography. Here, we present compelling evidence for overseas dispersal of frogs in the Indian Ocean region based on the discovery of two endemic species on Mayotte. This

Miguel Vences; D. Rodriguez Vieites; Frank Glaw; Henner Brinkmann; Joachim Kosuch; Michael Veith; Axel Meyer

2003-01-01

395

Relativistic quantum plasma dispersion functions  

Microsoft Academic Search

Relativistic quantum plasma dispersion functions (RQPDFs) are defined and the longitudinal and transverse response functions for an electron (plus positron) gas are written in terms of them. The dispersion is separated into Landau-damping, pair-creation and dissipationless regimes. Explicit forms are given for the RQPDFs in the cases of a completely degenerate distribution and a nondegenerate thermal (Jüttner) distribution. Particular emphasis

D. B. Melrose; J. I. Weise; J. McOrist

2006-01-01

396

Dispersal of Anoplophora glabripennis (Cerambycidae)  

Microsoft Academic Search

Asa bas isfor the development of both eradication and management s trategiesfor control of Anoplophora glabripennis Motschulsky (Asian longhorned beetle) investigations of A. glabripennis dispersal were undertaken in Gansu Province, China, in 1999. Data analysis of the Þrst year study of population dispersal, in which 16,000 adult A. glabripennis were marked and released (mass-mark recapture method), has shown that the

Michael T. Smith; Jay Bancroft; Guohong Li; Ruitong Gao; Stephen Teale

2001-01-01

397

Differentiation and Dispersal in Biofilms  

Microsoft Academic Search

Biofilm formation is now commonly associated with concepts of development, differentia- tion, and dispersal of microorganisms, and often more broadly with multicellular biologi- cal systems. This underlying theme of multicellularity among sessile microorganisms has undoubtedly attracted significant fundamental research interest to the field. This chapter will summarize and discuss aspects of cellular differentiation in biofilms, including micro- colony-based dispersal, autolysis

Jeremy S. Webb

398

Airflow dispersion in unsaturated soil  

Microsoft Academic Search

Dispersion data is abundant for water flow in the saturated zone but is lacking for airflow in unsaturated soil. However, for remediation processes such as soil vapour extraction, characterization of airflow dispersion is necessary for improved modelling and prediction capabilities. Accordingly, gas-phase tracer experiments were conducted in five soils ranging from uniform sand to clay at air-dried and wetted conditions.

T. Gidda; D. Cann; W. H. Stiver; R. G. Zytner

2006-01-01

399

Near real time vapor detection and enhancement using aerosol adsorption  

DOEpatents

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

Novick, Vincent J. (Downers Grove, IL); Johnson, Stanley A. (Countryside, IL)

1999-01-01

400

Near real time vapor detection and enhancement using aerosol adsorption  

DOEpatents

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01

401

QT dispersion in adult hypertensives.  

PubMed Central

Increased QT dispersion is associated with sudden cardiac death in congestive cardiac failure, hypertrophic cardiomyopathy and following myocardial infarction. Patients with hypertension--in particular, those with left ventricular hypertrophy (LVH)--are also at greater risk of sudden cardiac death. We examined whether QT dispersion, which is easily obtained from a routine ECG, correlates with LVH. One-hundred untreated patients with systemic hypertension and 78 normotensives had QT dispersion measured manually from a surface 12-lead electrocardiogram and two-dimensional echocardiography performed to measure interventricular septal thickness, posterior wall thickness and left ventricular internal diameter. Office blood pressure was also recorded. Multivariate analysis demonstrated significant relationships between QT dispersion and office systolic blood pressure, and left ventricular mass index. Manual measurement of QT dispersion might be a simple, noninvasive screening procedure to identify those hypertensives at greatest risk of sudden cardiac death in a third-world country.

Sani, Isa Muhammad; Solomon, Danbauchi Sulei; Imhogene, Oyati Albert; Ahmad, Alhassan Muhammad; Bala, Garko Sani

2006-01-01

402

Observation of expanding vapor cloud generated by hypervelocity impact  

Microsoft Academic Search

Observations of the expanding vapor cloud generated by the hypervelocity impact have been carried out. Under usual laboratory conditions, rock or ice materials cannot be vaporized completely. In order to investigate the expansion of a large amount of the vapor by complete vaporization caused by hypervelocity impact, we used a nylon projectile and measured the fundamental quantities of the vapor,

Toshihiko Kadono; Akira Fujiwara

1996-01-01

403

Carbon nanotube suspensions, dispersions, & composites  

NASA Astrophysics Data System (ADS)

Carbon Nanotubes (CNTs) are amazing structures that hold the potential to revolutionize many areas of scientific research. CNTs can be behave both as semiconductors and metals, can be grown in highly ordered arrays and patterns or in random orientation, and can be comprised of one graphene cylinder (single wall nanotube, SWNT) or several concentric graphene cylinders (multi-wall nanotube, MWNT). Although these structures are usually only a few nanometers wide, they can be grown up to centimeter lengths, and in massive quantities. CNTs can be produced in a variety of processes ranging from repeated combustion of organic material such as dried grass, arc-discharge with graphite electrodes, laser ablation of a graphitic target, to sophisticated chemical vapor deposition (CVD) techniques. CNTs are stronger than steel but lighter than aluminum, and can be more conductive than copper or semiconducting like silicon. This variety of properties has been matched by the wide variety of applications that have been developed for CNTs. Many of these applications have been limited by the inability of researchers to tame these structures, and incorporating CNTs into existing technologies can be exceedingly difficult and prohibitively expensive. It is therefore the aim of the current study to develop strategies for the solution processing and deposition of CNTs and CNT-composites, which will enable the use of CNTs in existing and emerging technologies. CNTs are not easily suspended in polar solvents and are extremely hydrophobic materials, which has limited much of the solution processing to organic solvents, which also cannot afford high quality dispersions of CNTs. The current study has developed a variety of aqueous CNT solutions that employ surfactants, water-soluble polymers, or both to create suspensions of CNTs. These CNT 'ink' solutions were deposited with a variety of techniques that have afforded many interesting structures, both randomly oriented as well as highly ordered CNT architectures, and electroactive devices such as sensors were subsequently produced from these materials. The aqueous solutions developed contain some of the longest CNTs to be suspended in water, which have many benefits for electronic and mechanical properties of the resultant composite materials. A non-covalent alternative to standard oxidative acid treatment was developed that has an equal ability to suspend CNTs in various solvents, but does not damage the CNT structure like the covalent functionalization with acids. This strategy has the potential to supplant a widely used method with improved CNT properties, faster and safer processing, and reduced environmental impact of waste materials. The results of this work also suggest that the conductivity of the CNTs may actually be improved by the processing, maximizing the utility if these materials. Electroactive devices have been successfully developed that exploit the unique electrical and physical properties of CNTs. Sensitive moisture sensors, which can possibly out-perform existing part per million sensors, have been developed with CNT inks and alumina nanoparticles. These sensor materials can be easily deposited on a wide variety of substrate materials and have an increased resistance to fouling compared to mesoporous sensors currently available. Electric double-layer supercapacitors based on novel cellulose-CNT composites have also been developed, and have commercially viable capacitance values, which make them a competitive technology with applications such as cell phones, computers, hand-held electronics, and possibly even electric automobiles. These supercapacitors employ less hazardous materials than competing technologies, and the ease of production of these devices could enable large-scale production of these materials.

Simmons, Trevor John

404

Enhancements for passive vapor extraction: The Hanford study  

SciTech Connect

Passive vapor extraction involves wells that are screened in the unsaturated zone and open to the atmosphere. Gas will flow out of the subsurface through the open well during periods of low barometric pressure. Field and modeling studies have been completed to evaluate enhancements for a passive vapor extraction system at a site contaminated with carbon tetrachloride on the Hanford nuclear reservation near Richland, Washington. During a 38-hour period of low barometric pressure, approximately 500 m{sup 3} of air were vented from the subsurface. Approximately 27 grams of carbon tetrachloride were removed from the subsurface during this same outflow event. On an annual basis, more than 15 kilograms of carbon tetrachloride have been removed from each of several passive extraction wells. Computer simulations based on the field data indicate that surface covers smaller than 30 m radius will result in relatively small enhancements of flow. However, with larger surface seals (i.e., up to 90 m radius), volumetric flow rates more than doubled. Simulations showed that check valves might increase the rate at which subsurface gases are extracted by a factor of nearly three. These estimates are sensitive to dispersion coefficients. If not properly designed, filters used to treat effluent gases from passive extraction systems can significantly reduce the effectiveness of these systems.

Ellerd, M.G.; Massmann, J.W.; Schwaegler, D.P. [Univ. of Washington, Seattle, WA (United States). Dept. of Civil Engineering; Rohay, V.J. [CH2M Hill Hanford Inc., Richland, WA (United States)

1999-05-01

405

Vapor phase mediated cellular uptake of sub 5 nm nanoparticles  

PubMed Central

Nanoparticles became an important and wide-used tool for cell imaging because of their unique optical properties. Although the potential of nanoparticles (NPs) in biology is promising, a number of questions concerning the safety of nanomaterials and the risk/benefit ratio of their usage are open. Here, we have shown that nanoparticles produced from silicon carbide (NPs) dispersed in colloidal suspensions are able to penetrate into surrounding air environment during the natural evaporation of the colloids and label biological cells via vapor phase. Natural gradual size-tuning of NPs in dependence to the distance from the NP liquid source allows progressive shift of the fluorescence color of labeled cells in the blue region according to the increase of the distance from the NP suspension. This effect may be used for the soft vapor labeling of biological cells with the possibility of controlling the color of fluorescence. However, scientists dealing with the colloidal NPs have to seriously consider such a NP's natural transfer in order to protect their own health as well as to avoid any contamination of the control samples.

2012-01-01

406

Vapor phase mediated cellular uptake of sub 5 nm nanoparticles  

NASA Astrophysics Data System (ADS)

Nanoparticles became an important and wide-used tool for cell imaging because of their unique optical properties. Although the potential of nanoparticles (NPs) in biology is promising, a number of questions concerning the safety of nanomaterials and the risk/benefit ratio of their usage are open. Here, we have shown that nanoparticles produced from silicon carbide (NPs) dispersed in colloidal suspensions are able to penetrate into surrounding air environment during the natural evaporation of the colloids and label biological cells via vapor phase. Natural gradual size-tuning of NPs in dependence to the distance from the NP liquid source allows progressive shift of the fluorescence color of labeled cells in the blue region according to the increase of the distance from the NP suspension. This effect may be used for the soft vapor labeling of biological cells with the possibility of controlling the color of fluorescence. However, scientists dealing with the colloidal NPs have to seriously consider such a NP's natural transfer in order to protect their own health as well as to avoid any contamination of the control samples.

Serdiuk, Tetiana; Lysenko, Vladimir; Skryshevsky, Valery A.; Géloën, Alain

2012-04-01

407

Organic vapor detection with fiber optic bead arrays  

NASA Astrophysics Data System (ADS)

The need for small, fast responding detection systems is growing and fiber-optic bead arrays offer a different approach to small sensor design. Sensor arrays are fabricated by inserting self-encoded microspheres into microwells etched into the distal face of an imaging fiber. Each imaging fiber is 0.5 - 1 mm in outer diameter and consists of 5,000 - 10,000 individually clad, 3 - 4 micrometers diameter optical fibers bundled together. The bundles are coherent, allowing each microsphere in a well to be addressed as an individual sensor. Microsphere sensors are silica or polymer beads (approximately 3 micrometers in diameter) impregnated with solvatochromic dyes. These dyes alter their fluorescence emission spectra in response to changes in vapor polarity, allowing analytes to be discriminated based on their signature fluorescence response over time. A computational network is trained to recognize these response patterns for each sensor type, allowing for identification of specific organic vapors. Each sensor type is cross- reactive, and has unique fluorescence response patterns to different analytes. The sensor types can be identified based on their unique responses, allowing their position to be registered by observing the identity of the response pattern toward a known standard. Such encoding enables array fabrication to be simplified since sensors can be randomly dispersed throughout the array, instead of specifically patterned within the array. Possible applications for bead array detectors include environmental and industrial monitoring, land mine detection, and medical diagnostics.

Stitzel, Shannon E.; Albert, Keith J.; Walt, David R.

1999-12-01

408

LANDFILL GAS CONVERSION TO LNG AND LCO{sub 2}. PHASE 1, FINAL REPORT FOR THE PERIOD MARCH 1998-FEBRUARY 1999  

SciTech Connect

Process designs and economics were developed to produce LNG and liquid carbon dioxide (CO{sub 2}) from landfill gas (LFG) using the Acrion CO{sub 2} wash process. The patented Acrion CO{sub 2} wash process uses liquid CO{sub 2} to absorb contaminants from the LFG. The process steps are compression, drying, CO{sub 2} wash contaminant removal and CO{sub 2} recovery, residual CO{sub 2} removal and methane liquefaction. Three flowsheets were developed using different residual CO{sub 2} removal schemes. These included physical solvent absorption (methanol), membranes and molecular sieves. The capital and operating costs of the flowsheets were very similar. The LNG production cost was around ten cents per gallon. In parallel with process flowsheet development, the business aspects of an eventual commercial project have been explored. The process was found to have significant potential commercial application. The business plan effort investigated the economics of LNG transportation, fueling, vehicle conversion, and markets. The commercial value of liquid CO{sub 2} was also investigated. This Phase 1 work, March 1998 through February 1999, was funded under Brookhaven National laboratory contract 725089 under the research program entitled ``Liquefied Natural Gas as a Heavy Vehicle Fuel.'' The Phase 2 effort will develop flowsheets for the following: (1) CO{sub 2} and pipeline gas production, with the pipeline methane being liquefied at a peak shaving site, (2) sewage digester gas as an alternate feedstock to LFG and (3) the use of mixed refrigerants for process cooling. Phase 2 will also study the modification of Acrion's process demonstration unit for the production of LNG and a market site for LNG production.

COOK,W.J.; NEYMAN,M.; SIWAJEK,L.A.; BROWN,W.R.; VAN HAUWAERT,P.M.; CURREN,E.D.

1998-02-25

409

Simultaneous Water Vapor and Dry Air Path Length Measurements with the Keck Interferometer Nuller  

NASA Astrophysics Data System (ADS)

K-band phase and group delay measurements of atmospheric turbulence are used as part of the Keck Interferometer nuller cophasing system to provide high-bandwidth path length compensation at N band. Because of atmospheric dispersion, the path length fluctuations from dry air and water vapor must be estimated separately, and the computation of the N-band feedforward quantities from the K-band measurements is described. Simultaneous K and N-band sky data are presented that show good correspondence with the underlying atmospheric models. Simultaneous power spectra of dry air and water vapor path length turbulence measured on an 85 m baseline with the Keck Interferometer over 44 nights between 2007 June and 2009 July are also presented. From the median power spectra, the rms path length fluctuations at band from water vapor are found to be 48 times smaller than those for dry air, and the absolute level of the water vapor path length fluctuations is found to be a factor of 2 smaller than predicted based on archival data from the CSO test radio interferometer. It is postulated that part of the difference is attributable to surface-layer water vapor turbulence, which would be smaller at the elevation of the Keck telescopes than for the test antennas, similar to surface-layer effects seen in dry air seeing at Mauna Kea. The midfrequency power spectral amplitude better characterizes the residuals for a feedforward compensation system, and this value is found to be a factor of 65 smaller at K band for water vapor than for dry air; the difference compared to the ratio of the rms values is attributable to the lower effective wind speed of the water vapor turbulence, and thus lower control bandwidths are required for compensation than a simple scaling based on rms fluctuations would indicate. The water vapor coherence time is also shown to have modest correlations with both precipitable water vapor and the dry air coherence time, although the variability of the water vapor turbulence strength is larger than that of the dry air turbulence.

Colavita, M. M.

2010-05-01

410

Confined zone dispersion flue gas desulfurization demonstration  

SciTech Connect

The CZD process involves flue gas post-treatment, physically located between a boiler's outlet and its particulate collector, which in the majority of cases is an electrostatic precipitator. The features that distinguish this process from other similar injection processes are: Injection of an alkaline slurry directly into the duct, instead of injection of dry solids into the duct ahead of a fabric filter. Use of an ultrafine calcium/magnesium hydroxide, type S pressure-hydrated dolomitic lime. This commercial product is made from plentiful, naturally occurring dolomite. Low residence time, made possibly by the high effective surface area of the type S lime. Localized dispersion of the reagent. Slurry droplets contact only part of the gas while the droplets are drying, to remove up to 50 percent of the SO{sub 2} and significant amounts of NO{sub x}. The process uses dual fluid rather than rotary atomizers. Improved ESP performance via gas conditioning from the increased water vapor content, and lower temperatures. Supplemental conditioning with SO{sub 3} is not believed necessary for satisfactory removal of particulate matter. The waste product is composed of magnesium and calcium sulfite and sulfate, with some excess lime. This product mixed with fly ash is self-stabilizing because of the excess lime values, and thus tends to retain heavy metals in insoluble forms within the fly ash.

Not Available

1991-09-05

411

ON-LINE CALCULATOR: VAPOR INTRUSION MODELING  

EPA Science Inventory

Migration of volatile chemicals from the subsurface into overlying buildings is called vapor intrusion (VI). Volatile organic chemicals in contaminated soils or groundwater can emit vapors, which may migrate through subsurface soils and may enter the indoor air of overlying build...

412

Evaluation of the BioVapor Model  

EPA Science Inventory

The BioVapor model addresses transport and biodegradation of petroleum vapors in the subsurface. This presentation describes basic background on the nature and scientific basis of environmental transport models. It then describes a series of parameter uncertainty runs of the Bi...

413

Vapor sampling and analysis plan. Revision 1  

SciTech Connect

This document is a plan which serves as the contractual agreement between the Characterization Program, Sampling Operations, Oak Ridge National Laboratory, and PNL tank vapor program. The scope of this plan is to provide guidance for the sampling and analysis of vapor samples from both SST and DST tanks

Homi, C.S.

1995-10-10

414

IN SITU SOIL VAPOR EXTRACTION TREATMENT  

EPA Science Inventory

Soil vapor extraction (SVE) is designed to physically remove volatile compounds, generally from the vadose or unsaturated zone. t is an in situ process employing vapor extraction wells alone or in combination with air injection wells. acuum blowers supply the motive force, induci...

415

Dynamic Response of Geometrically Constrained Vapor Bubbles  

Microsoft Academic Search

Geometrically constrained vapor bubbles are important in many microelectromechanical systems (MEMS), such as actuators and micro-pumps. We consider a two-dimensional model of a vapor bubble between two horizontal parallel boundaries held at different temperatures. When the temperatures are constant, a steady state can be achieved such that evaporation near the contact lines at the hot bottom plate is balanced by

Vladimir S. Ajaev; G. M. Homsy

2001-01-01

416

Predicting vapor pressures using neural networks  

Microsoft Academic Search

Calculating surface vapor pressures of volatile inorganic components, nitric acid, hydrochloric acid and ammonia, is essential for modeling condensation and evaporation processes occurring in atmospheric aerosols. The vapor pressure of these compounds depends on temperature, relative humidity, phase state, and particle composition, and their calculation consumes an enormous amount of computer time in Eulerian photochemical\\/aerosol models. Here we use a

Sudhakar Potukuchi; Anthony S. Wexler

1997-01-01

417

An atlas of extragalactic water vapor masers  

Microsoft Academic Search

We present an atlas of extragalactic water vapor masers. As of 2007, one hundred galaxies have been detected as sources of water vapor maser emission, two thirds of them discovered since 2003. Extragalactic water masers fall in at least three categories: those associated with nuclear jets or winds, those in starbursts or star-forming regions, and those in AGN accretion disks.

J. Braatz; P. Kondratko; L. Greenhill; J. Condon; C. Henkel; N. Gugliucci; L. Hao; M. Reid; J. Moran; K.-Y. Lo

2007-01-01

418

ANALYSIS OF HEAT PIPE VAPOR DYNAMICS  

Microsoft Academic Search

The transient behavior of vapor flow in heat pipes is analyzed numerically using a two dimensional compressible Row model. The vapor core response to changes in the evaporation and condensation rates following a sudden increase, or decrease, in the input heat flux, or the condensation temperature is studied. The numerical scheme is fully implicit using a staggered grid to overcome

F. ISSACCI; I. CATTON; A. HEISS; N. M. GHONIEM

1989-01-01

419

Improved Rubidium Vapor Cells for Frequency Standards.  

National Technical Information Service (NTIS)

This report is divided into three areas of study that are designed to develop understanding of the magnitude and the causes of composition changes in Rb vapor cells: production of contaminant gases, depletion of Rb vapor, and diffusion of Rb into glass. E...

M. P. R. Thomsen L. J. Stief R. J. Fallon

1968-01-01

420

On the mechanism of acoustic droplet vaporization  

Microsoft Academic Search

It has been observed in the past that micrometer sized droplets can be vaporized into gas bubbles by the application of diagnostic ultrasound. This paper will discuss the possible underlying mechanism of acoustic droplet vaporization (ADV) including acoustic cavitation, acoustic heating, shape oscillations during acoustic irradiation, and hydrodynamic cavitation. Experiments were performed on droplet emulsions as well as on single

Oliver D. Kripfgans; Paul L. Carson; J. Brian Fowlkes

2002-01-01

421

The search for Water Vapor on Titan  

Microsoft Academic Search

The discovery of carbon dioxide on Titan in 1981 opened a new vista in the chemistry of reducing atmospheres. Because the principal mechanism for the production of carbon dioxide is the reaction of CO with the hydroxyl radical OH, a search began for both CO and water vapor at this time. Water vapor should be injected into Titan's atmosphere from

R. E. Samuelson; G. L. Bjoraker; A. Coustenis; Th. Encrenaz; A. Salama; Th. de Graauw

1997-01-01

422

Improved Rubidium Vapor Cells for Frequency Standards.  

National Technical Information Service (NTIS)

The report is divided into three areas of study that are designed to develop understanding of the magnitude and the causes of composition changes in Rb vapor cells: depletion of Rb vapor, production of contaminant gases, and diffusion of Rb into glass. Ea...

M. P. R. Thomsen L. J. Stief R. J. Fallon

1968-01-01

423

Absence of a vestigial vapor pressure paradox  

Microsoft Academic Search

The enigmatic but much accepted vapor pressure paradox for oriented lipid bilayer samples was recently justified theoretically. Subsequently, recent experiments have shown that there is no vapor pressure paradox. The first result of this paper is to consider another degree of freedom that reverses the previous theoretical conclusion, so that theory and experiment are now in agreement that there is

John F. Nagle; John Katsaras

1999-01-01

424

Vaporization of synthetic fuels. Final report. [Thesis  

Microsoft Academic Search

The problem of transient droplet vaporization in a hot convective environment is examined. The main objective of the present study is to develop an algorithm for the droplet vaporization which is simple enough to be feasibly incorporated into a complete spray combustion analysis and yet will also account for the important physics such as liquid-phase internal circulation, unsteady droplet heating

W. A. Sirignano; S. C. Yao; A. Y. Tong; D. Talley

1983-01-01

425

Water and Water Vapor Penetration Through Coatings  

Microsoft Academic Search

Water and water vapor transport in two-layer systems where one layer acts as water retarder are analyzed. In the experimental work, four external paints supposed to protect the underlying structure against water under common service conditions are applied on glass fiber reinforced concrete substrates. The water absorption coefficient and the effective water vapor diffusion coefficient are chosen as evaluation parameters

Jitka Podêbradská; Jaroslava Drchalová

2002-01-01

426

Sodium vapor heat pipe laser cell  

Microsoft Academic Search

A sodium heat pipe cell containing high-voltage discharge plates was constructed to study the band absorption of light by the sodium dimer and to determine the feasibility of creating a metal vapor laser. Spectrographic measurements indicated that the increase in sodium dimer population with temperature resulted in 90% light absorption at 970 K. High-voltage discharges in the sodium vapor dissociated

J. E. Deverall; G. W. York

1978-01-01

427

An Application of Oil Vaporization Evaluation Methods  

Microsoft Academic Search

This paper describes and quantifies the benefits of residual oil vaporization in an enhanced recovery gas injection project. Vaporized oil is recovered as natural gas liquid (NGL) when the injected gas is produced. In the reservoir application studied, 20% of the liquid hydrocarbons produced were being recovered as NGL. (VC)

W. W. Fleckenstein; L. S. Bouck; P. D. Hudgens; M. E. Querin; L. L. Williams

1992-01-01

428

Water vapor permeation in polyimide membranes  

Microsoft Academic Search

The study of the influence of water vapor in the feed stream of a mixed gas membrane separation system is of considerable practical importance. Water vapor may plasticize the membrane, it may undergo competitive sorption with other gas species and it can form clusters as it permeates. In this work, a modified mixed gas permeation system was employed to accurately

George Q. Chen; Colin A. Scholes; Greg G. Qiao; Sandra E. Kentish

2011-01-01

429

VAPOR PRESSURE OF POLYPHENYL COOLANT AND COMPONENTS  

Microsoft Academic Search

Studies were undertaken to measure the vapor pressure of organic coolant ; materials over the temperature range 450 to 900 deg F. The vapor pressure of ; diphenyl, Santowax R and ortho-, meta-, and para-terphenyl was determined ; experimentally. (W.L.H.)

Silvey

1959-01-01

430

Lubricant Vapor Pressure Derived from Evaporation Loss  

Microsoft Academic Search

A method is presented for obtaining vapor pressures over the temperature range of interest in engine lubrication (300–500 F). The determination is based on the saturation efficiency of an air stream and the relationship between vapor pressure and evaporation loss. All data required are readily obtained from the ASTM Evaporation Test Method D 972-56 which is already used in connection

John F. Coburn

1969-01-01

431

Quantitative organic vapor-particle sampler  

DOEpatents

A quantitative organic vapor-particle sampler for sampling semi-volatile organic gases and particulate components. A semi-volatile organic reversible gas sorbent macroreticular resin agglomerates of randomly packed microspheres with the continuous porous structure of particles ranging in size between 0.05-10 .mu.m for use in an integrated diffusion vapor-particle sampler.

Gundel, Lara (Berkeley, CA); Daisey, Joan M. (Walnut Creek, CA); Stevens, Robert K. (Cary, NC)

1998-01-01

432

Partial oxidation of methane on silica-supported silicomolybdic acid catalysts in an excess amount of water vapor  

SciTech Connect

Partial oxidation of methane into oxygenates such as methanol and formaldehyde on highly dispersed MoO{sub 3}/SiO{sub 2} catalysts was studied in an excess amount of water vapor. The reaction was carried out at 873 K using gases consisting of oxygen, methane, and water vapor. The selectivity of oxygenates was found to be a strong function of water vapor, and increased as the fraction of water vapor in a feed gas increased. Inversely, the selectivity of CO and CO{sub 2} in the products decreased as the fraction of water vapor increased. This is ascribed to the formation of silicomolybdic acid (SMA:H{sub 4}SiMo{sub 12}O{sub 40}) over the silica surface during the reaction, partially evidenced by IR measurements. Accordingly, silica-supported SMA catalysts were prepared and applied to the partial oxidation of methane under the same conditions as described above to see if SMA works as the active species for the reaction. Although SMA easily decomposed into SiO{sub 2} and MoO{sub 3} at 873 K without water vapor, it worked well for the production of oxygenates when the fraction of water vapor was more than 50% in the feed gas. The yield of oxygenates increased up to 20% of methane as the fraction of water vapor was around 60%; methane conversion was about 25% and the selectivity of oxygenates was 90%. In this paper, the authors will emphasize that SMA formed on the silica surface are the active species of silica-supported MoO{sub 3} catalysts for the partial oxidation of methane in an excess amount of water vapor.

Sugino, Tomomi; Kido, Ayako; Azuma, Naoto; Ueno, Akifumi; Udagawa, Yasuo

2000-02-15

433

Dynamics of Acoustically Vaporized Microdroplets  

NASA Astrophysics Data System (ADS)

A combined theoretical and computational approach is utilized to understand the bubble evolution dynamics resulting by vaporizing the superheated dodecafluoropentane (DDFP, C5F12) microdroplets via an acoustic perturbation. This work is inspired by a developmental gas embolotherapy technique for cancer treatment by infarcting tumors using selectively formed gas bubbles. The evolution process comprises of three regimes; an initial linear rapid spherical growth followed by a linear compressed oval shaped growth and finally a slow asymptotic non-linear spherical growth. The bubble evolution process compares quite well with the ultra high-speed experiments. The final bubble radius scales linearly with the initial droplet radius and is approximately five times the initial droplet radius. A pressure pulse with amplitude approximately twice as that of ambient conditions is observed. The pressure pulse wavelength increases with an increasing droplet size whereas the pulse amplitude is weakly dependent on droplet size. This work is supported by NIH grant R01EB006476.

Qamar, Adnan; Wong, Zheng Zheng; Fowlkes, J. Brian; Bull, Joseph

2010-11-01

434

Spin relaxation in alkali vapors  

NASA Astrophysics Data System (ADS)

In this dissertation, I describe a series of experimental and theoretical studies directed toward the understanding of spin-relaxation mechanisms in an alkali vapor. I present a large volume of new data that allows prediction of spin-relaxation rates under a wider variety of circumstances than was possible before. These results can be described by a model consisting of four relaxation mechanisms: relaxation on the vessel walls, in collisions with a buffer gas, in alkali singlet dimers, and what I refer to as alkali-alkali relaxation. The latter half of this work is devoted to a search for a theoretical model of alkali-alkali relaxation. I show that the previously held belief that alkali-alkali relaxation occurs during binary alkali collisions cannot be reconciled with the data presented here, and discuss possible alternate theories. Finally, I suggest that relaxation in metastable alkali trimer complexes may be the microscopic mechanism best able to explain these new results.

Kadlecek, Stephen John

1999-11-01

435

Atomic vapor laser isotope separation  

SciTech Connect

Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

Stern, R.C.; Paisner, J.A.

1985-11-08

436

Vapor Inhalation of Alcohol in Rats  

PubMed Central

Alcohol dependence constitutes a neuroadaptive state critical for understanding alcoholism, and various methods have been utilized to induce alcohol dependence in animals, one of which is alcohol vapor exposure. Alcohol vapor inhalation provides certain advantages over other chronic alcohol exposure procedures that share the ultimate goal of producing alcohol dependence in rats. Chronic alcohol vapor inhalation allows the experimenter to control the dose, duration, and pattern of alcohol exposure. Also, this procedure facilitates testing of somatic and motivational aspects of alcohol dependence. Chronic exposure to alcohol vapor produces increases in alcohol-drinking behavior, increases in anxiety-like behavior, and reward deficits in rats. Alcohol vapor inhalation as a laboratory protocol is flexible, and the parameters of this procedure can be adjusted to accommodate the specific aims of different experiments. This unit describes the options available to investigators using this procedure for dependence induction, when different options are more or less appropriate, and the implications of each.

Gilpin, Nicholas W.; Richardson, Heather N.; Cole, Maury; Koob, George F.

2008-01-01

437

Advection-dispersion modelling tools: what about numerical dispersion?  

PubMed

In general the transport of dissolved substances and fine suspended particles is governed by the one-dimensional advection-dispersion equation. In order to model the transport of dissolved substances and fine suspended particles, the advection-dispersion equation is incorporated into commonly used urban drainage modelling tools such as InfoWorks CS (Wallingford Software, United Kingdom) and MOUSE (DHI Software, Denmark). Two examples show the use of InfoWorks CS and MOUSE using standard model settings. Modelling results using tracer experiments show that numerical model parameters need to be altered in order to calibrate the model. Using tracer experiments as a model calibration tool, it is shown that a non-negligible amount of dispersion is generated by InfoWorks CS and MOUSE and that it is in fact the numerical dispersion that is calibrated. PMID:16206840

Bouteligier, R; Vaes, G; Berlamont, J; Flamink, C; Langeveld, J G; Clemens, F

2005-01-01

438

Engineering vapor-deposited polyimides  

NASA Astrophysics Data System (ADS)

The vapor deposition polymerization (VDP) of PMDA-ODA polyimide was studied parametrically to produce microcapsules and thin films with desirable properties and quality for the Inertial Confinement Fusion (ICF) experiments. The mechanical properties and gas permeability were determined at temperatures from 10 to 573 K. The VDP polyimide possessed distinct properties including lower gas permeability and stronger tensile properties from those of solution-cast Kapton, which were attributed to the presence of cross-linking. Processing parameters determining the properties of the VDP polyimide were identified: (1) utilizing air instead of nitrogen as the atmosphere of imidization increased the permeability by 140%, lowered the activation energy for permeation, and reduced the tensile strength by 30% without affecting the Young's modulus; (2) imidizing at faster heating rates increased the permeability by up to 50% and reduced the activation energy for permeation with 50% lowered tensile strength and impervious Young's modulus; (3) bi-axial stretching increased the permeability by up to three orders of magnitude. Analyses via IR spectroscopy, X-ray diffraction, and density measurement revealed that the effects of the processing parameters were results of the modifications in the crystallinity and molecular weight. The VDP polyimide underwent minor degradation in the tensile strength and elongation at break with unaffected Young's modulus and permeability upon absorbing 120 MGy of beta-radiation. Substituting a fluorinated dianhydride monomer, 6FDA, for PMDA in the optimized VDP process yielded 6FDA-ODA polyimide microcapsules and films with 50-fold increased permeability and comparable mechanical properties. The results of this study enable the production of polyimide microcapsules that will greatly facilitate the ICF experiments, and will broaden the applications of vapor-deposited polyimides in other technology fields.

Tsai, Feng-Yu

439

Stacked vapor fed amtec modules  

DOEpatents

The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

Sievers, Robert K. (North Huntingdon, PA)

1989-01-01

440

33 CFR 154.808 - Vapor control system, general.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Vapor control system, general. 154.808 Section...FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Vapor Control Systems § 154.808 Vapor control system, general. (a) A...

2013-07-01

441

Improving pigment dispersing in powder coatings with block copolymer dispersants  

Microsoft Academic Search

The effect of three block copolymer dispersants with a poly(2-vinylpyridine) anchor block and a poly(?-caprolactone) buoy\\u000a block on the dispersing of TiO2 pigments in a polyester powder coating has been studied with digital image analysis on scanning electron micrographs. The\\u000a mixing in a lab-scale extruder resulted in a virtually complete break-up of the pigment agglomerates. The average TiO2 particle size

Francis L. Duivenvoorde; Cornelus F. van Nostrum; Jozua Laven; Rob van der Linde

2000-01-01

442

Velocity Dispersions Across Bulge Types  

SciTech Connect

We present first results from a long-slit spectroscopic survey of bulge kinematics in local spiral galaxies. Our optical spectra were obtained at the Hobby-Eberly Telescope with the LRS spectrograph and have a velocity resolution of 45 km/s (sigma*), which allows us to resolve the velocity dispersions in the bulge regions of most objects in our sample. We find that the velocity dispersion profiles in morphological classical bulge galaxies are always centrally peaked while the velocity dispersion of morphologically disk-like bulges stays relatively flat towards the center--once strongly barred galaxies are discarded.

Fabricius, Maximilian; Bender, Ralf; Hopp, Ulrich [University Observatory of the Ludwig-Maximilians University (LMU) (Germany); Max-Planck Institute for Extraterrestrial Physics (MPE) (Germany); Saglia, Roberto; Drory, Niv [Max-Planck Institute for Extraterrestrial Physics (MPE) (Germany); Fisher, David [Department of Astronomy, University of Texas at Austin (United States)

2010-06-08

443

Light propagation in an atomic medium with steep and sign-reversible dispersion  

SciTech Connect

We show that ground-state Zeeman coherence prepared by two-photon Raman transitions in alkali atoms results in steep controllable and sign-reversible dispersion. Pulse propagation with small negative as well as positive group velocity of light (-c/5100 and c/41 000) in a Cs vapor cell is reported. Energy exchange between copropagating light components through long-lived Zeeman coherence with enhanced absorption or transmission has been observed.

Akulshin, A. M. [School of Physics, University of Melbourne, Victoria 3010 (Australia); P.N. Lebedev Institute of Physics, Moscow 117924 (Russian Federation); Cimmino, A.; Opat, G.I. [School of Physics, University of Melbourne, Victoria 3010 (Australia); Sidorov, A.I.; Hannaford, P. [Swinburne University of Technology, Victoria 3122 (Australia)

2003-01-01

444

Tropical upper tropospheric water vapor distribution  

NASA Astrophysics Data System (ADS)

Water vapor is a powerful greenhouse gas and its fast response to temperature makes it a good candidates for creating feedback mechanisms that could modify global climate substantially. For one of the most important climate system on the Earth, the tropical climate system, it is particularly relevant because one of the major determinants has been identified as clear sky OLR averaged over the entire Tropics. Due to the radiative importance of water vapor in higher altitudes and drier regions, the major (but not exclusive) focus of our attention is the tropical upper tropospheric water vapor in the subsiding regions. Furthermore, the nonlinearity of Outgoing Longwave Radiation (OLR) responses to humidity entails a more detailed statistical analysis than zonally averaged humidity. The main vehicle to conduct this statistical analysis is Probability Distribution Function (PDF) of water vapor mixing ratio. The general task of this study is to investigate water vapor distribution, maintenance and radiative impacts, as well evaluation of General Circulation Model (GCM) water vapor performances. Previous research on water vapor maintenance had lead to Large Scale Advection hypothesis, which serves as the basis for our study. Traditional observation has been lacking in both coverage and accuracy, Tiros Observational Vertical Sounder (TOVS) water vapor data, assisted by more recent CEPEX tropical sounding, are employed in the data analysis. The observational chapter is devoted to the examination of the morphology, regional, seasonal variation and vertical variation of PDF, possible climate impact as well as the effects of resolution are also examined. Our data analysis shows that TOVS water vapor PDF has a skewed appearance. A linear transform procedure is shown to be able to bring PDF from different layer to a close fit. The mean and deviation of water vapor mixing ratio display a positive correlation. These information are further used to evaluate GCM water vapor performance. Similar data analysis procedures are performed on GCM water vapor PDF's and results are compared with TOVS counterparts. GCM PDF shows similar morphological features, but its capability in capturing the seasonality needs improvement. Our theoretical effort concentrates on two aspects. The initial PDF problem and the geometry of humidity distribution field The moist tail of humidity PDF is found to be influenced by the mixing ratio inside convective region and the mass flux into the subsiding region. It is also demonstrated that the combination of subsidence drying and stretching could result in a power law of water vapor concentration field.

Zhang, Hui

2002-09-01

445

Surface-Wave Dispersion Computations.  

National Technical Information Service (NTIS)

Fundamental-mode Love- and Rayleigh-wave dispersion computations for multilayered, perfectly-elastic media were studied. The speed of these computations was improved, and the accuracy brought under full control. With sixteen decimal digits employed in the...

F. Schwab L. Knopoff

1969-01-01

446

Acoustic Rectification in Dispersive Media.  

National Technical Information Service (NTIS)

It is shown that the shapes of acoustic radiation-induced static strain and displacement pulses (rectified acoustic pulses) are defined locally by the energy density of the generating waveform. Dispersive properties are introduced analytically by assuming...

J. H. Cantrell

2008-01-01

447

Development of polymer concrete for dike insulation at LNG (Liquid Natural Gas) facilities. Final report, August 1983-July 1984  

SciTech Connect

An insulating polymer concrete (IPC) composite has been developed for possible use as a dike insulation material at Liquid Natural Gas (LNG) storage facilities. Using hermetically sealed glass nodules or expanded perlite aggregates and unsaturated polyester resins, a new class of lightweight polymer concretes can be manufactured. Two application procedures have been identified and shown to be feasible in laboratory studies. Precast IPC composite panels 1-in thick can be bonded to concrete substrates using epoxy gel type adhesives or mortars. Cast-in-place IPC to concrete substrates have been shown to have good bonding and insulating characteristics. Modifications of the mix design to improve the workability and sagging of the IPC for installation on vertical or sloped surfaces is necessary.

Fontana, J.J.; Steinberg, M.

1984-11-01

448

Dispersion coefficients for coastal regions  

SciTech Connect

The Nuclear Regulatory Commission (NRC) has undertaken an extensive atmospheric dispersion research and measurement program from which it is intended will emerge improved predictive techniques for employment in licensing decisions and for emergency planning and response. Through this program the NRC has conducted field measurement programs over a wide range of geographic and topographic locations, and are using the acquired tracer and meteorological measurements to evaluate existing dispersion models and prediction techniques, and to develop new techniques when necessary.

MacRae, B.L.; Kaleel, R.J.; Shearer, D.L.

1983-03-01

449

Pigment Dispersion Syndrome - Update 2003  

Microsoft Academic Search

\\u000a Pigment dispersion syndrome (PDS) is a unique and fascinating entity. It is far more prevalent, actually by an order of magnitude,\\u000a than previously suspected, comprising 2.45% of the screened Caucasian population in one study [76]. PDS and pigmentary glaucoma (PG) are characterized by disruption of the iris pigment epithelium (IPE) and deposition of\\u000a the dispersed pigment granules throughout the anterior

Robert Ritch

450

Stimulation of vapor nucleation on perfect and imperfect hexagonal lattice surfaces  

SciTech Connect

Monte Carlo simulations of water vapor nucleation on a perfect crystal surface and on a surface with defects are performed. Mass exchange with the vapor phase is modeled by using an open ensemble. Cluster-substrate interaction is described in terms of conventional atom-atom potentials. The Hamiltonian of the system includes expressions for electrostatic, polarization, exchange, and dispersion interactions. The Gibbs free energy and work of adsorption are calculated by Monte Carlo simulation in the bicanoinical ensemble. The microscopic structure of nuclei is analyzed in terms of pair correlation functions. Periodic boundary conditions are used to simulate an infinite substrate surface. Molecule-substrate and molecule-molecule long-range electrostatic interactions are calculated by summing the Fourier harmonics of the electrostatic potential. Dispersion interactions are calculated by direct summation over layers of unit cells. Nucleation on a surface with matching structure follows a layer-by-layer mechanism. The work of adsorption per molecule of a monolayer on the substrate surface has a maximum as a function of nucleus size. The steady rate of nucleation of islands of supercritical size is evaluated. The work of adsorption per molecule for layer-by-layer film growth is an oscillating function of cluster size. As a function of layer number, it has a minimum depending on the vapor pressure. The electric field generated by a microscopic surface protrusion destroys the layered structure of the condensate and eliminates free-energy nucleation barriers. However, point lattice defects do not stimulate explosive nucleation.

Shevkunov, S. V. [St. Petersburg State Polytechnic University (Russian Federation)], E-mail: root@svsh.tu.neva.ru

2008-12-15

451

Shock vaporization of carbonate and sulfate minerals  

NASA Astrophysics Data System (ADS)

Strong shock waves induced by impacts can cause vaporization of rocks and minerals. The products of such process play important roles in planetary differentiation (Yakovlev et al., Geochem. International, 38, 1027, 2000) and in effecting the planetary climate. Many experiments and computer simulations have been performed to simulate the Chicxulub impact at Cretaceous/Tertiary boundary (see, for example, Pierazzo et al., J. Geophys. Res., 103, 28607, 1998 and Pope et al., J. Geophys. Res., 102, 21645, 1997). However, the pressure range for incipient and complete vaporization of carbonates and sulfates are not well constrained, especially, for minerals with various initial porosities. Furthermore, evidence for chemical species in the products of vaporized carbonate and sulfate minerals is almost non-existing. In this study, we employed published Hugoniot data for carbonate and sulfate minerals. By using the methods described in Ahrens (J. Appl. Phys., 43, 2443, 1972) and Ahrens and O'Keefe (The Moon, 4, 214, 1972), we calculated the entropy associated with the thermodynamic states produced by hypervelocity impacts at various velocities for carbonate and sulfate minerals with different initial porosities. The results were compared with the entropy of incipient vaporization and complete vaporization of these minerals to determine the degree of vaporization due to impacts. Moreover, these results are utilized to guide our experimental study in speciation reactions in shock-induced vaporization of carbonates and sulfates.

Shen, A. H.; Ahrens, T. J.; O'Keefe, J. D.

2001-12-01

452

Absence of a vestigial vapor pressure paradox  

NASA Astrophysics Data System (ADS)

The enigmatic but much accepted vapor pressure paradox for oriented lipid bilayer samples was recently justified theoretically. Subsequently, recent experiments have shown that there is no vapor pressure paradox. The first result of this paper is to consider another degree of freedom that reverses the previous theoretical conclusion, so that theory and experiment are now in agreement that there is no vapor pressure paradox. However, this analysis also suggests the possibility of a vestigial vapor pressure paradox that would rationalize why the vapor pressure paradox was historically so persistent and that would have led to an improved protocol for obtaining bilayer structure. This vestigial vapor pressure paradox would involve a phase transition as a function of applied osmotic pressure. We test this possibility experimentally using combined neutron and x-ray scattering data. The conclusion from these experiments is that there is not even a vestigial vapor pressure paradox. However, this negative result validates an improved method for calibrating osmotic pressure in x-ray studies of oriented samples.

Nagle, John F.; Katsaras, John

1999-06-01

453

CO(2) DIAL measurements of water vapor.  

PubMed

CO(2) lidars have heretofore been used to measure water vapor concentrations primarily using the 10R(20) line at 10.247 microm, which has a strong overlap with a water vapor absorption line. This paper discusses the use of that line as well as other CO(2) laser lines for which the absorption coefficients are weaker. The literature on measurement of water vapor absorption coefficients using CO(2) lasers is reviewed, and the results from four laboratories are shown to be generally consistent with each other after they are normalized to the same partial pressure, temperature, and ethylene absorption coefficient for the 1P(14) CO(2) laser line; however, the agreement with the Air Force Geophysics Laboratory's HITRAN and FASCOD 2 spectral data tapes is not good either for the water vapor absorption lines or for the water vapor continuum. Demonstration measurements of atmospheric water vapor have been conducted using the Mobile Atmospheric Pollutant Mapping System, a dual CO(2) lidar system using heterodyne detection. Results are discussed for measurements using three sets of laser line pairs covering a wide range of water vapor partial pressures. PMID:20490006

Grant, W B; Margolis, J S; Brothers, A M; Tratt, D M

1987-08-01

454

Vaporization of perfluorocarbon droplets using optical irradiation  

PubMed Central

Micron-sized liquid perfluorocarbon (PFC) droplets are currently being investigated as activatable agents for medical imaging and cancer therapy. After injection into the bloodstream, superheated PFC droplets can be vaporized to a gas phase for ultrasound imaging, or for cancer therapy via targeted drug delivery and vessel occlusion. Droplet vaporization has been previously demonstrated using acoustic methods. We propose using laser irradiation as a means to induce PFC droplet vaporization using a method we term optical droplet vaporization (ODV). In order to facilitate ODV of PFC droplets which have negligible absorption in the infrared spectrum, optical absorbing nanoparticles were incorporated into the droplet. In this study, micron-sized PFC droplets loaded with silica-coated lead sulfide (PbS) nanoparticles were evaluated using a 1064 nm laser and ultra-high frequency photoacoustic ultrasound (at 200 and 375 MHz). The photoacoustic response was proportional to nanoparticle loading and successful optical droplet vaporization of individual PFC droplets was confirmed using photoacoustic, acoustic, and optical measurements. A minimum laser fluence of 1.4 J/cm2 was required to vaporize the droplets. The vaporization of PFC droplets via laser irradiation can lead to the activation of PFC agents in tissues previously not accessible using standard ultrasound-based techniques.

Strohm, Eric; Rui, Min; Gorelikov, Ivan; Matsuura, Naomi; Kolios, Michael

2011-01-01

455

Carbon fibers from vapor phase hydrocarbons  

SciTech Connect

Less expensive carbon fibers may become available in the future by production from vapor phase hydrocarbons. In this process, iron based catalytic particles of a few nanometers diameter grow carbon filaments when they are exposed to hydrocarbon vapor near 1000 C. These filaments are of nanometer diameter but may be thickened by deposition of carbon from the vapor phase. The mechanical properties of the fibers made by this process resemble those of medium quality commercial fibers; the electrical and thermal conductivities are also desirable. 9 refs.

Tibbetts, G.G.

1990-01-01

456

Measuring Water Vapor with Differential Absorption Lidar  

NASA Astrophysics Data System (ADS)

Despite the need for global measurements of water vapor profiles with low bias and high vertical resolution there is currently no operational remote sensing system that would deliver such data. A possible solution to this problem is offered by the differential absorption lidar (DIAL) approach. The basic principle of operation will be described and some background on atmospheric light absorption by water vapor will be given. DLR's airborne water vapor DIAL system WALES represents the currently most advanced system worldwide using a multiwavelength technique to cover the troposphere and lower stratosphere simultaneously. A few examples of measurements made with this system will illustrate the power of this active remote sensing method.

Wirth, Martin

457

Water vapor retrieval over many surface types  

SciTech Connect

In this paper we present a study of of the water vapor retrieval for many natural surface types which would be valuable for multi-spectral instruments using the existing Continuum Interpolated Band Ratio (CIBR) for the 940 nm water vapor absorption feature. An atmospheric code (6S) and 562 spectra were used to compute the top of the atmosphere radiance near the 940 nm water vapor absorption feature in steps of 2.5 nm as a function of precipitable water (PW). We derive a novel technique called ``Atmospheric Pre-corrected Differential Absorption`` (APDA) and show that APDA performs better than the CIBR over many surface types.

Borel, C.C.; Clodius, W.C.; Johnson, J.

1996-04-01

458

Detection and Analysis of Water Vapor Transport  

NASA Astrophysics Data System (ADS)

Water vapor, though a minor constituent of Earth's atmosphere, plays a major role in the atmospheric radiation budget and the global water cycle. Atmospheric water vapor concentrations are highly variable due to the complex interplay between their sources (evaporation) and sinks (condensation and precipitation) in combination with transport and mixing. They strongly decrease with temperature and thus with altitude. Accurate measurement of water vapor is essential for better understanding its transport and cloud formation in the atmosphere and their impact on both weather and climate. To this end the institute develops and deploys lidars and in situ hygrometers onboard aircraft.

Kiemle, Christoph; Schäfler, Andreas; Voigt, Christiane

459

Process for vaporizing a liquid hydrocarbon fuel  

DOEpatents

The object of the invention is to provide a process for vaporizing liquid hydrocarbon fuels efficiently and without the formation of carbon residue on the apparatus used. The process includes simultaneously passing the liquid fuel and an inert hot gas downwardly through a plurality of vertically spaed apart regions of high surface area packing material. The liquid thinly coats the packing surface, and the sensible heat of the hot gas vaporizes this coating of liquid. Unvaporized liquid passing through one region of packing is uniformly redistributed over the top surface of the next region until all fuel has been vaporized using only the sensible heat of the hot gas stream.

Szydlowski, Donald F. (East Hartford, CT); Kuzminskas, Vaidotas (Glastonbury, CT); Bittner, Joseph E. (East Hartford, CT)

1981-01-01

460

Determination of the dispersion constant in a constrained vapor bubble thermosyphon  

Microsoft Academic Search

The isothermal profiles of the extended meniscus in a quartz cuvette were measured in a gravitational field using an image analyzing interferometer which is based on computer enhanced video microscopy of the naturally occurring interference fringes. The experimental results for heptane and pentane menisci were analyzed using the extended Young-Laplace equation. These isothermal results characterized the interfacial force field in-situ

Sunando. Dasgupta; Joel L. Plawsky; Peter C. Wayner Jr.

1993-01-01

461

Determination of the Dispersion Constant in a Constrained Vapor Bubble Thermosyphon.  

National Technical Information Service (NTIS)

The isothermal profiles of the extended meniscus in a quartz cuvette were measured in a gravitational field using an image analyzing interferometer which is based on computer enhanced video microscopy of the naturally occurring interference fringes. The e...

S. Dasgupta J. L. Plawsky P. C. Wayner

1995-01-01

462

Determination of the dispersion constant in a constrained vapor bubble thermosyphon  

Microsoft Academic Search

The isothermal profiles of the extended meniscus in a quartz cuvette were measured in a gravitational field using an image analyzing interferometer which is based on computer enhanced video microscopy of the naturally occurring interference fringes. The experimental results for heptane and pentane menisci were analyzed using the extended Young Laplace Equation. These isothermal results characterized the interfacial force field

Sunando Dasgupta; Joel L. Plawsky; Peter C. Wayner Jr.

1995-01-01

463

Vapor barrier properties of polycaprolactone montmorillonite nanocomposites: effect of clay dispersion  

Microsoft Academic Search

Different compositions of poly(?-caprolactone) (PCL) and (organo-modified) montmorillonite were prepared by melt blending or catalyzed ring opening polymerization of ?-caprolactone. Microphase composites were obtained by direct melt blending of PCL and sodium montmorillonite (MMT-Na+). Exfoliated nanocomposites were obtained by in situ ring opening polymerization of ?-caprolactone with an organo-modified montmorillonite (MMT-(OH)2) by using dibutyltin dimethoxide as an initiator\\/catalyst. Intercalated nanocomposites

Giuliana Gorrasi; Mariarosaria Tortora; Vittoria Vittoria; Eric Pollet; Bénédicte Lepoittevin; Michael Alexandre; Philippe Dubois

2003-01-01

464

Solar pumped, alkali vapor laser  

NASA Astrophysics Data System (ADS)

High power lasers based in space have been considered as sources for power transmission, laser propulsion, materials processing and space defense. The feasibility of such systems is based on the cost per unit power delivered, with detailed studies indicating that light weight has a greater impact on cost than laser efficiency. Solar radiation is a natural source of power for these devices and two methods for conversion of solar radiation to laser radiation can be considered. An indirectly solar pumped laser would first convert the solar radiation to electricity or longer wavelength blackbody radiation which is then used to power the laser. A directly longer wavelength blackbody radiation which is then used to power the laser. A directly pumped solar laser would utilize a portion of te solar spectrum to directly pump the laser medium, eliminating the intervening step and substantially reducing the systems weight and complexity. Detailed comparisons showed a directly pumped laser with an overall efficiency of only 1.5 percent can compete with an indirectly energized solar laser with an overall efficiency of ten percent. With this in mind, a concept for a directly solar pumped laser was developed based on an alkali vapor (sodium) as the laser medium.

Ham, David; Defaccio, Mark A.

1987-09-01

465

Probe for measurement of velocity and density of vapor in vapor plume  

SciTech Connect

A probe is disclosed which directs a light beam through a vapor plume in a first direction at a first angle ranging from greater than 0{degree} to less than 90{degree}, reflecting the light beam back through the vapor plume at a 90{degree} angle, and then reflecting the light beam through the vapor plume a third time at a second angle equal to the first angle, using a series of mirrors to deflect the light beam while protecting the mirrors from the vapor plume with shields. The velocity, density, temperature and flow direction of the vapor plume may be determined by a comparison of the energy from a reference portion of the beam with the energy of the beam after it has passed through the vapor plume. 10 figs.

Berzins, L.V.; Bratton, B.A.; Fuhrman, P.W.

1997-03-11

466

Probe for measurement of velocity and density of vapor in vapor plume  

DOEpatents

A probe which directs a light beam through a vapor plume in a first direction at a first angle ranging from greater than 0.degree. to less than 90.degree., reflecting the light beam back through the vapor plume at a 90.degree. angle, and then reflecting the light beam through the vapor plume a third time at a second angle equal to the first angle, using a series of mirrors to deflect the light beam while protecting the mirrors from the vapor plume with shields. The velocity, density, temperature and flow direction of the vapor plume may be determined by a comparison of the energy from a reference portion of the beam with the energy of the beam after it has passed through the vapor plume.

Berzins, Leon V. (Livermore, CA); Bratton, Bradford A. (Bethel Island, CA); Fuhrman, Paul W. (Livermore, CA)

1997-01-01

467

Impact of the vertical velocity scenario on modeling water vapor transport in the TTL  

NASA Astrophysics Data System (ADS)

To study transport and transformation of water vapor in the TTL we analyze high-resolution water measurements from the tropical aircraft mission SCOUT-O3 in Northern Australia. Therefore backtrajectories are initialized along the flight tracks and minimum saturation water, calculated from the minimum temperatures along the trajectories, is compared to the measurements. Furthermore, we assess the impact of the vertical velocity scenario on modeling stratospheric water vapor by calculating the trajectories in various kinematic and diabatic scenarios, with the vertical velocity either pressure tendency or deduced from diabatic heating rates. The extremely well agreement between trajectory reconstructed water vapor and measurements demonstrates that the water vapor set point in the TTL is primarily determined by the recent Lagrangian saturation history, with an additional moistening effect of deep convection. The impact of the vertical velocity scenario on the average tropical stratospheric water budget turns out to be small. However, modeling high-resolution in-situ water measurements favors a diabatic scenario, with reduced dispersion and no subsidence in the upper TTL and a more efficient sampling of cold point temperatures, compared to a kinematic scenario.

Ploeger, F.; Konopka, P.; Guenther, G.; Grooss, J.; Mueller, R.; Schiller, C.

2009-12-01

468

Vapor phase extraction and separation of rare earths from bastnaesite concentrate mediated by vapor complexes  

Microsoft Academic Search

Vapor phase extraction and mutual separation characteristics of rare earths mediated by vapor complex in the LnCl3?Kcl systems (Ln = rare earth) were investigated using chemical vapor transport along a temperature gradient. Bastnaesite concentrate (LnFCO3) and potassium carbonate were used as raw material and precursor of the complex former, KCl, respectively oxyfluoride is complete within 2 h at 1000°Cin the

Tetsuya Ozaki; Toshiki Miyazawa; Kuniaki Murase; Ken-ichi Machida; Gin-ya Adachi

1996-01-01

469

Preparation of vapor grown carbon fibers by microwave pyrolysis chemical vapor deposition  

Microsoft Academic Search

Vapor grown carbon fibers have been prepared without any catalyst by microwave pyrolysis chemical vapor deposition using CH4 as source gas and N2 as carrier gas at 1050–1150°C. Scanning electron microscopy images reveal that vapor grown carbon fibers are made up of sub-fibers which are hexagonal and layer-like carbon. Polarized light images indicate that sub-fibers are formed by high-texture carbon

Ji-zhao Zou; Xie-rong Zeng; Xin-bo Xiong; Han-ling Tang; Long Li; Qiang Liu; Zhi-qiang Li

2007-01-01

470

Characteristics of Vapor Flashing Geothermal Plants.  

National Technical Information Service (NTIS)

A study of the important parameters of a vapor flashing plant and characteristics of its major components is presented. The optimum flashing temperature was calculated by numerical method, and the effects of wellhead pressure and number of stages on power...

R. K. Ahluwalia J. C. S. Chou

1974-01-01

471

Chemical vapor infiltration in single fiber bundles.  

National Technical Information Service (NTIS)

Chemical vapor infiltration (CVI) in single fiber bundles is studied under isothermal conditions. Understanding infiltration dynamics in single bundles is essential to process design and modeling efforts. Deposition of pyrolytic carbon in carbon-fiber bun...

D. J. Devlin R. P. Currier R. S. Barbero

1990-01-01

472

Copper Vapor Lasers for Isotope Separation.  

National Technical Information Service (NTIS)

Copper vapor lasers for uranium isotope separation were investigated. The laser system is composed of an oscillator and an amplifier, the diameters of which are 28 and 50 mm, respectively. An inverter electric power supply which synchronizes the laser fre...

C. Yamanaka E. Fujiwara T. Naka T. Takeda T. Yamanaka

1986-01-01

473

Study of the Constrained Vapor Bubble Thermosyphon.  

National Technical Information Service (NTIS)

The objective of this effort is to better understand the physics of evaporation, condensation, and fluid flow as they affect the heat transfer processes in a constrained vapor bubble heat exchanger (CVBHX). This CVBHX consists of a small enclosed containe...

P. C. Wayner J. L. Plawsky

2000-01-01

474

Calibration of Lemair Mercury Vapor Detector.  

National Technical Information Service (NTIS)

A project was initiated to calibrate the Lemair Mercury Vapor Detector. The detector was calibrated using the sampling and generating procedure reported by Nelson. A modification of the analytical procedure was necessary to insure complete mercury recover...

E. J. Smith P. Diamond

1968-01-01

475

Hanford Chemical Vapors Worker Concerns & Exposure Evaluation.  

National Technical Information Service (NTIS)

Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site in eastern Washington State are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and survei...

T. J. Henderson

2006-01-01

476

Chemical vapor infiltration using microwave energy  

DOEpatents

A method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.

Devlin, David J. (Los Alamos, NM); Currier, Robert P. (Los Alamos, NM); Laia, Jr., Joseph R. (Los Alamos, NM); Barbero, Robert S. (Santa Cruz, NM)

1993-01-01

477

The Absorption Spectrum of Sodium Vapor  

ERIC Educational Resources Information Center

Procedures and discussion of an experiment to be used in an undergraduate course in spectroscopy are presented. The experiment involves the measurement of the absorption spectrum of sodium vapor. (DT)

Ashby, R. A.; Gotthard, H. W.

1974-01-01

478

40 CFR 796.1950 - Vapor pressure.  

Code of Federal Regulations, 2013 CFR

...addition, chemicals that are likely to be gases at ambient temperatures and which...likely to transport and persist in soils and water. Such chemicals are less...by removing dissolved and entrained gases until the measured vapor pressure...

2013-07-01

479

Vapor Pressure of Diffusion Pump Oils.  

National Technical Information Service (NTIS)

This citation summarizes a one-page announcement of technology available for utilization. A thermogravimetric procedure has been developed for the determination of the vapor pressure of diffusion pump oils by using a Knudsen effusion cell in conjunction w...

1981-01-01

480

VAPOR PRESSURE DISTRIBUTION OF SELECTED ORGANIC CHEMICALS  

EPA Science Inventory

A tabulation of vapor pressures for organic chemical products currently considered for inclusion in fugitive emissions regulations was prepared. For each of the 378 chemicals (or groups of chemicals) identified by the Emission Standards and Engineering Division, the following dat...

481

Mechanical Deterioration of Mgo by Water Vapor.  

National Technical Information Service (NTIS)

The effect of exposure to the laboratory atmosphere on the fracture stress and Young's modulus of polycrystalline magnesium oxide was studied. The observed degradation of mechanical properties was attributed to chemical attack by atmospheric water vapor. ...

K. R. Janowski R. C. Rossi

1967-01-01

482

Personal benzene vapor detection device. Final report  

SciTech Connect

A badge was developed as a personal vapor detector to record the cumulative exposure of an individual to benzene vapor. The badge consisted of an optical fiber, small sections of which were coated with a membrane specific for the adsorption of benzene vapor. Membranes made of polyethylene and nylon, and filled with zeolite were applied to a silver halide fiber. Following exposure, the fiber was subjected to Fourier Transform Infrared (FTIR) spectrometry. The coating successfully retained the benzene vapor for several days. A concentration of 100,000 parts per million (ppm) could be detected. Concentrations of dichlorobenzene of 80,000ppm were also detected. Unique absorbance peaks were used to distinguish the two compounds. It was possible to reuse the sensor. However, the desired detectability range of 1 to 100ppm was not met.

Glatkowski, P.; Druy, M.

1992-07-01

483

Vapor-Pressure Measurements by Effusion Methods.  

National Technical Information Service (NTIS)

Vapor pressure measurements were made on FeCl2, FeBr2, FeI2, Sb, Bi, Cd, Mg, Pb, FeCl3, and VCl2 using the Knudsen and torsion effusion methods and on FeCl3-NaCl mixtures, Au2Cl6 and MgNi2 using only the Knudsen method. Apparent vapor pressures calculated...

A. Landsberg A. Adams S. D. Hill

1977-01-01

484

Vapor chamber in high power LEDs  

Microsoft Academic Search

The vapor chamber has already been confirmed that its anti-gravity, high effective thermal conductivity and suited on the high heat flux of heat source as the integral heat spreader. This article describes how to evaluate the thermal-performance of LED vapor chamber-based plate with VCTM V1.0, which has existed in the thermal-module industry for a year or so especially in high

Jung-Chang Wang; Chun-Ling Huang

2010-01-01

485

Multicomponent fuel vaporization at high pressures.  

SciTech Connect

We extend our multicomponent fuel model to high pressures using a Peng-Robinson equation of state, and implement the model into KIVA-3V. Phase equilibrium is achieved by equating liquid and vapor fugacities. The latent heat of vaporization and fuel enthalpies are also corrected for at high pressures. Numerical simulations of multicomponent evaporation are performed for single droplets for a diesel fuel surrogate at different pressures.

Torres, D. J. (David J.); O'Rourke, P. J. (Peter J.)

2002-01-01

486

Transient, compressible heat-pipe vapor dynamics  

Microsoft Academic Search

This paper describes the numerical modeling of a simulated heat-pipe vapor transient. The compressible, unsteady, axisymmetric Navier-Stokes equations were solved numerically using MacCormack's explicit finite difference method. The flow field development during the transient is studied in detail. To test the accuracy of the numerical model, a simulated heat-pipe vapor space was also experimentally studied. Steady state axial pressure variations

W. J. Bowman; J. E. Hitchcock

1988-01-01

487

Water vapor adsorption on geothermal reservoir rocks  

Microsoft Academic Search

The quantification of the amount of water retained in geothermal reservoir rocks allows a more realistic estimation of reserves for vapor-dominated geothermal reservoirs. If the measured desorption isotherm resembles the production characteristics of a geothermal system, understanding of the adsorption\\/desorption hysteresis will aid the design of reinjection processes.Adsorption\\/desorption isotherms of both nitrogen and water vapor on Berea sandstone and a

Shubo Shang; Roland N. Horne; Henry J. Ramey

1995-01-01

488

Diode pumped alkali vapor fiber laser  

Microsoft Academic Search

A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into

Stephen A. Payne; Raymond J. Beach; Jay W. Dawson; William F. Krupke

2007-01-01

489

Diode pumped alkali vapor fiber laser  

Microsoft Academic Search

A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into

Stephen A. Payne; Raymond J. Beach; Jay W. Dawson; William F. Krupke

2006-01-01

490

Update on photoselective vaporization of the prostate  

Microsoft Academic Search

Photoselective vaporization of the prostate (PVP) with a potassium titanyl phosphate (KTP) laser may be the most promising\\u000a new technology applied to the treatment of benign prostatic hyperplasia (BPH). The specific laser light characteristics and\\u000a the ideal interactions between KTP lasers and prostatic tissue result in an even and efficient vaporization of the prostate\\u000a and the formation of a clearly

Petros Sountoulides; Jean J. M. C. H. de la Rosette

2008-01-01

491

Vapor chamber in high performance server  

Microsoft Academic Search

This article describes how to evaluate the thermal-performance of vapor chamber-based thermal module, which has existed in the thermal-module industry for a year or so especially in server application. Thermal-performance of the thermal module with the vapor chamber can be determined within several seconds by using the final formula associated with thermal-performance experimental method deduced in this paper. From the

Jung-Chang Wang; Teng-Chieh Chen

2009-01-01

492

Liquid–vapor isotherm in a closed single-component system with droplets or bubbles in smooth crevices  

Microsoft Academic Search

A thermodynamic model in order to study a single-component system where droplets or bubbles are inside smooth crevices is presented. Liquid–vapor interface curvature radius can change its sign as the droplet or bubble volume change. The results suggest that there is always dispersed phase inside smooth crevices of microscopic dimensions, even in the expected single-phase region. Thus, the occurrence of

Marcelo Lago; Rafael Martin; Mariela Araujo

2003-01-01

493

Fabrication of thin films of bismuth selenide using novel single-source precursors by metal organic chemical vapor deposition  

Microsoft Academic Search

A metal-organic compound, Bi[(SePiPr2)2N]3 has been synthesized and used as a single-source precursor for the deposition of bismuth selenide thin films via low-pressure metal-organic chemical vapor deposition. Crystalline thin films of rhombohedral Bi2Se3 have been deposited on glass substrates. The films have been characterized by X-ray powder diffraction, scanning electron microscopy and energy dispersive analysis of X-rays.

J. Waters; D. Crouch; P. O'Brien; Jin-Ho Park

2003-01-01

494

Elaboration of (Bi1?xSbx)2Te3 thin films by metallorganic chemical vapor deposition  

Microsoft Academic Search

Metallorganic chemical vapor deposition (MOCVD) of (Bi1¡x Sbx )2Te3 (0.25• x • 0:9) using trimethylbismuth, triethylantimony and diethyltellerium has been obtained on pyrex substrates. A polycrystalline structure has been confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) observation. Energy dispersive X-ray spectroscopy (EDX) has been used to determine the chemical composition. We have studied the solid composition of

B. Aboulfarah; A. Mzerd; A. Giani; A. Boulouz; F. Pascal-Delannoy; A. Foucaran; A. Boyer

1999-01-01

495

Modeling and Simulation of Effects of Turbulence on Vaporization, Mixing and Combustion of Liquid-Fuel Sprays  

Microsoft Academic Search

The objective of this work is twofold. Firstly, the effects of turbulence intensity variations on the turbulent droplet dispersion,\\u000a vaporization and mixing for non-reacting sprays (with and without swirl) are pointed out. Secondly, the effects of the coupling\\u000a of the turbulence modulation with external parameters, such as swirl intensity, on turbulent spray combustion are analyzed\\u000a in configurations of engineering importance.

A. Sadiki; M. Chrigui; J. Janicka; M. R. Maneshkarimi

2005-01-01

496

Electrospray organometallic chemical vapor deposition—A novel technique for preparation of II–VI quantum dot composites  

Microsoft Academic Search

A novel technique combining electrospray and organometallic chemical vapor deposition (OMCVD) has been developed for the synthesis of new II–VI quantum dot composites. CdSe nanocrystals (quantum dots) of selected size are dispersed in a pyridine\\/acetonitrile mixture. The nanocrystals are transferred by electrospray into the growth zone of an OMCVD reactor and codeposited on a ZnSe matrix grown from hydrogen selenide

M. Danek; K. F. Jensen; C. B. Murray; M. G. Bawendi

1994-01-01

497

New S1 vibronic level assignments for s-tetrazine vapor: Polarization and lifetime measurements  

NASA Astrophysics Data System (ADS)

New fluorescence excitation and dispersed SVL fluorescence spectra of s-tetrazine vapor in supersonic expansions of helium and argon are reported. A forbidden in-plane-polarized component of the A~1B3u-X~1Ag transition is discovered at (0, 0) + 578 cm-1 with a type-B band contour in rotationally resolved excitation spectra obtained with a single-frequency cw ring dye laser. Linewidth measurements of single rovibronic transitions provide data to calculate lifetimes of low-lying S1 vibronic states of the isolated molecule. Depending on the vibrational mode involved, the lifetime varies from 0.05 to greater than 1 nsec. The number of cold-band assignments in the absorption spectrum of s-tetrazine vapor now confirmed by analysis of SVL fluorescence spectra increases from three to ten.

Brumbaugh, Donald V.; Haynam, Christopher A.; Levy, Donald H.

1982-08-01

498

Melting, ablation, and vapor phase condensation during atmospheric passage of the Bjurbole meteorite  

NASA Astrophysics Data System (ADS)

A detailed study of the Bjurbole fusion crust using scanning electron microscopy (SEM) and energy dispersive analysis (EDS) shows that filamentary crystals and ablation spheres may form on the meteoroid surface. Filamentary crystals, hollow spheres, and porous regions of the surface point to a period of intense vapor phase activity during atmospheric passage. Filamentary crystals can be divided into three categories on the basis of bulk composition and morphology. Two types of filamentary crystals are vapor phase condensation products formed during atmospheric entry of the meteoroid. The other type forms by the interaction of seawater with the fusion surface. The density and composition of ablation spheres varies with the flight orientation of the meteorite. The size range and composition of iron-nickel spheres on the surface of Bjurbole are similar to spheres collected in the stratosphere. A comparison of stratospheric dust collections with meteorite surfaces may provide further insight into the mechanisms of meteoroid entry into planetary atmospheres.

Rietmeijer, F. J. M.; MacKinnon, I. D. R.

1984-02-01

499

A heated vapor cell unit for dichroic atomic vapor laser lock in atomic rubidium.  

PubMed

The design and performance of a compact heated vapor cell unit for realizing a dichroic atomic vapor laser lock (DAVLL) for the D(2) transitions in atomic rubidium is described. A 5 cm long vapor cell is placed in a double-solenoid arrangement to produce the required magnetic field; the heat from the solenoid is used to increase the vapor pressure and correspondingly the DAVLL signal. We have characterized experimentally the dependence of important features of the DAVLL signal on magnetic field and cell temperature. For the weaker transitions both the amplitude and gradient of the signal are increased by an order of magnitude. PMID:17902946

McCarron, Daniel J; Hughes, Ifan G; Tierney, Patrick; Cornish, Simon L

2007-09-01

500

A heated vapor cell unit for dichroic atomic vapor laser lock in atomic rubidium  

SciTech Connect

The design and performance of a compact heated vapor cell unit for realizing a dichroic atomic vapor laser lock (DAVLL) for the D{sub 2} transitions in atomic rubidium is described. A 5 cm long vapor cell is placed in a double-solenoid arrangement to produce the required magnetic field; the heat from the solenoid is used to increase the vapor pressure and correspondingly the DAVLL signal. We have characterized experimentally the dependence of important features of the DAVLL signal on magnetic field and cell temperature. For the weaker transitions both the amplitude and gradient of the signal are increased by an order of magnitude.

McCarron, Daniel J.; Hughes, Ifan G.; Tierney, Patrick; Cornish, Simon L. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)

2007-09-15