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Fluid flow modeling of resin transfer molding for composite material wind turbine blade structures. (open access)

Fluid flow modeling of resin transfer molding for composite material wind turbine blade structures.

Resin transfer molding (RTM) is a closed mold process for making composite materials. It has the potential to produce parts more cost effectively than hand lay-up or other methods. However, fluid flow tends to be unpredictable and parts the size of a wind turbine blade are difficult to engineer without some predictive method for resin flow. There were five goals of this study. The first was to determine permeabilities for three fabrics commonly used for RTM over a useful range of fiber volume fractions. Next, relations to estimate permeabilities in mixed fabric lay-ups were evaluated. Flow in blade substructures was analyzed and compared to predictions. Flow in a full-scale blade was predicted and substructure results were used to validate the accuracy of a full-scale blade prediction.
Date: June 1, 2004
Creator: Cairns, Douglas S. (Montana State University, Bozeman, MT) & Rossel, Scott M. (Montana State University, Bozeman, MT)
Object Type: Report
System: The UNT Digital Library
Biotransformation involved in sustained reductive removal of uranium in contaminant aquifers (open access)

Biotransformation involved in sustained reductive removal of uranium in contaminant aquifers

This report summarizes progress made from June 2003 to July 2004. During this period research focused on further understanding the factors controlling the growth and activity of dissimilatory metal reducers in subsurface environments and the application of these findings to better design of strategies for in situ bioremediation of uranium.
Date: June 1, 2004
Creator: Lovley, Derek R.
Object Type: Report
System: The UNT Digital Library
International biosecurity symposium : securing high consequence pathogens and toxins : symposium summary. (open access)

International biosecurity symposium : securing high consequence pathogens and toxins : symposium summary.

The National Nuclear Security Administration (NNSA) Office of Nonproliferation Policy sponsored an international biosecurity symposium at Sandia National Laboratories (SNL). The event, entitled 'Securing High Consequence Pathogens and Toxins', took place from February 1 to February 6, 2004 and was hosted by Dr. Reynolds M. Salerno, Principal Member of the Technical Staff and Program Manager of the Biosecurity program at Sandia. Over 60 bioscience and policy experts from 14 countries gathered to discuss biosecurity, a strategy aimed at preventing the theft and sabotage of dangerous pathogens and toxins from bioscience facilities. Presentations delivered during the symposium were interspersed with targeted discussions that elucidated, among other things, the need for subsequent regional workshops on biosecurity, and a desire for additional work toward developing international biosecurity guidelines.
Date: June 1, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Design Features and Technology Uncertainties for the Next Generation Nuclear Plant (open access)

Design Features and Technology Uncertainties for the Next Generation Nuclear Plant

This report presents the conclusions, observations, and recommendations of the Independent Technology Review Group (ITRG) regarding design features and important technology uncertainties associated with very-high-temperature nuclear system concepts for the Next Generation Nuclear Plant (NGNP). The ITRG performed its reviews during the period November 2003 through April 2004.
Date: June 1, 2004
Creator: Ryskamp, John M.; Hildebrandt, Phil; Baba, Osamu; Ballinger, Ron; Brodsky, Robert; Chi, Hans-Wolfgang et al.
Object Type: Report
System: The UNT Digital Library
Overview of US heavy-ion fusion progress and plans (open access)

Overview of US heavy-ion fusion progress and plans

Significant experimental and theoretical progress has been made in the U.S. heavy ion fusion program on high-current sources, transport, final focusing, chambers and targets for inertial fusion energy (IFE) driven by induction linac accelerators seek to provide the scientific and technical basis for the Integrated Beam Experiment (IBX), an integrated source-to-target physics experiment recently included in the list of future facilities planned by the U.S. Department of Energy. To optimize the design of IBX and future inertial fusion energy drivers, current HIF-VNL research is addressing several key issues (representative, not inclusive): gas and electron cloud effects which can exacerbate beam loss at high beam perveance and magnet aperture fill factors; ballistic neutralized and assisted-pinch focusing of neutralized heavy ion beams; limits on longitudinal compression of both neutralized and un-neutralized heavy ion bunches; and tailoring heavy ion beams for uniform target energy deposition for high energy density physics (HEDP) studies.
Date: June 1, 2004
Creator: Logan, B. G.
Object Type: Report
System: The UNT Digital Library
Non-Invasive Diagnostics to Measure Physical Properties in High-Level Wastes (open access)

Non-Invasive Diagnostics to Measure Physical Properties in High-Level Wastes

The viscosity of a Hanford waste stream is potentially an indicator of its composition, including solids load, and of how well it has been mixed. Viscosity could be a useful control variable that might indicate the need for heating or dilution, for example. However, traditional off-line measurements are slow and samples can be difficult to take. Pausing processing to take samples disrupts and slows down production schedules and so, if viscosity measurements are necessary, requires increased capacity in the whole process. An alternative viscosity measurement that does not require sampling, and that is fast would be more useful than traditional techniques.
Date: June 1, 2004
Creator: Pfund, David M. & Pappas, Richard A.
Object Type: Report
System: The UNT Digital Library
Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock (open access)

Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock

The Department of Energy Environmental Management Program is faced with two major issues involving two-phase flow in fractured rock; specifically, transport of dissolved contaminants in the Vadose Zone, and the fate of Dense Nonaqueous Phase Liquids (DNAPLs) below the water table. Conceptual models currently used to address these problems do not correctly include the influence of the fractures, thus leading to erroneous predictions. Recent work has shown that it is crucial to understand the topology, or ''structure'' of the fluid phases (air/water or water/DNAPL) within the subsurface. It has also been shown that even under steady boundary conditions, the influence of fractures can lead to complex and dynamic phase structure that controls system behavior, with or without the presence of a porous rock matrix. Complicated phase structures within the fracture network can facilitate rapid transport, and lead to a sparsely populated and widespread distribution of concentrated contaminants; these qualities are highly difficult to describe with current conceptual models. The focus of our work is to improve predictive modeling through the development of advanced conceptual models for two-phase flow in fractured rock.
Date: June 1, 2004
Creator: Nicholl, Michael J.; Glass, Robert J.; Rajaram, Harihar & Wood, Thomas R.
Object Type: Report
System: The UNT Digital Library
Chemical Speciation of Americium, Curium and Selected Tetravalent Actinides in High Level Waste (open access)

Chemical Speciation of Americium, Curium and Selected Tetravalent Actinides in High Level Waste

Large volumes of high-level waste (HLW) currently stored in tanks at DOE sites contain both sludges and supernatants. The sludges are composed of insoluble precipitates of actinides, radioactive fission products, and nonradioactive components. The supernatants are alkaline carbonate solutions, which can contain soluble actinides, fission products, metal ions, and high concentrations of major electrolytes including sodium hydroxide, nitrate, nitrite, phosphate, carbonate, aluminate, sulfate, and organic complexants. The organic complexants include several compounds that can form strong aqueous complexes with actinide species and fission products including ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA), nitrilotriacetic acid (NTA), iminodiacetic acid (IDA), citrate, glycolate, gluconate, and degradation products, formate and oxalate. The goal of this project is to determine the effects of hydrolysis, carbonate complexation, and metal ion displacement on trivalent and selected tetravalent actinide speciation in the presence of organic chelates present in tank waste and to use these data to develop accurate predictive thermodynamic models for use in chemical engineering applications at Hanford and other DOE sites.
Date: June 1, 2004
Creator: Felmy, Andrew R.
Object Type: Report
System: The UNT Digital Library
Improvement to Pipeline Compressor Engine Reliability Through Retrofit Micro-Pilot Ignition System (open access)

Improvement to Pipeline Compressor Engine Reliability Through Retrofit Micro-Pilot Ignition System

This report documents the second year's effort towards a 3-year program to develop micropilot ignition systems for existing pipeline compressor engines. In essence, all Phase II goals and objectives were met. We intend to proceed with the Phase III research plan, as set forth by the applicable Research Management Plan. The objective for Phase II was to further develop and optimize the micropilot ignition system for large bore, slow speed engines operating at low compression ratios. The primary elements of Micropilot Phase II were to evaluate the results for the 4-cylinder system prototype developed for Phase I, then optimize this system to demonstrate the technology's readiness for the field demonstration phase. In all, there were twelve (12) tasks defined and executed to support objectives in a stepwise fashion. Task-specific approaches and results are documented in this report. Research activities for Micropilot Phase II were conducted with the understanding that the efforts are expected to result in a commercial product to capture and disseminate the efficiency and environmental benefits of this new technology. Commercially-available fuel injection products were identified and applied to the program where appropriate. Modifications to existing engine components were kept to a minimum. This approach will minimize the …
Date: June 1, 2004
Creator: Bestor, Ted
Object Type: Report
System: The UNT Digital Library
Application of Advanced Gamma Ray Detection Concepts Combined with Real-time Compton Suppression for Nondestructive, Gamma Ray Characterization of Remote-handled Waste (open access)

Application of Advanced Gamma Ray Detection Concepts Combined with Real-time Compton Suppression for Nondestructive, Gamma Ray Characterization of Remote-handled Waste

Nondestructive gamma ray characterization of remote-handled waste is significantly complicated by the presence of Compton scattering in the detector and waste matrix produced by the intense cesium gamma ray. This research seeks to understand the photophysics of a new type of inorganic scintillation gamma ray detector, optimize the combination of this gamma ray detector with a Compton guard detector, develop new Monte Carlo solution algorithms for modeling Compton scattering in the waste, and to model the real time intensity of cesium produced Compton scattering. A successful research program will provide the fundamental information needed to design and develop advanced Compton spectrometers for assay of remote handled waste and new higher sensitivity spectrometers for environmental measurements.
Date: June 1, 2004
Creator: McIlwain, Michael
Object Type: Report
System: The UNT Digital Library
Low Temperature Sorbents for Removal of Sulfur Compounds from Fluid Feed Streams (open access)

Low Temperature Sorbents for Removal of Sulfur Compounds from Fluid Feed Streams

A sorbent material is provided comprising a material reactive with sulfur, a binder unreactive with sulfur and an inert material, wherein the sorbent absorbs the sulfur at temperatures between 30 and 200 C. Sulfur absorption capacity as high as 22 weight percent has been observed with these materials.
Date: June 1, 2004
Creator: Siriwardane, Ranjani
Object Type: Patent
System: The UNT Digital Library
Progress in the Peeling-Ballooning Model of Elms: Toroidal Rotation and 3d Nonlinear Dynamics (open access)

Progress in the Peeling-Ballooning Model of Elms: Toroidal Rotation and 3d Nonlinear Dynamics

Understanding the physics of the H-Mode pedestal and edge localized modes (ELMs) is very important to next-step fusion devices for two primary reasons: (1) The pressure at the top of the edge barrier (''pedestal height'') strongly impacts global confinement and fusion performance, and (2) large ELMs lead to localized transient heat loads on material surfaces that may constrain component lifetimes. The development of the peeling-ballooning model has shed light on these issues by positing a mechanism for ELM onset and constraints on the pedestal height. The mechanism involves instability of ideal coupled ''peeling-ballooning'' modes driven by the sharp pressure gradient and consequent large bootstrap current in the H-mode edge. It was first investigated in the local, high-n limit [1], and later quantified for non-local, finite-n modes in general toroidal geometry [2,3]. Important aspects are that a range of wavelengths may potentially be unstable, with intermediate n's (n {approx} 3-30) generally limiting in high performance regimes, and that stability bounds are strongly sensitive to shape [Fig l(a)], and to collisionality (i.e. temperature and density) [4] through the bootstrap current. The development of efficient MHD stability codes such as ELITE [3,2] and MISHKA [5] has allowed detailed quantification of peeling-ballooning stability bounds …
Date: June 1, 2004
Creator: Snyder, P. B.; Wilson, H. R.; Xu, X. Q. & Webster, A. J.
Object Type: Article
System: The UNT Digital Library
Hydrologic Tests at Characterization Wells R-9i, R-13, R-19, R-22, and R-31, Revision 1 (open access)

Hydrologic Tests at Characterization Wells R-9i, R-13, R-19, R-22, and R-31, Revision 1

Hydrologic information is essential for environmental efforts at Los Alamos National Laboratory. Testing at new characterization wells being drilled to the regional aquifer (''R wells'') to improve the conceptual hydrogeologic model of the Pajarito Plateau is providing such information. Field tests were conducted on various zones of saturation penetrated by the R wells to collect data needed for determining hydraulic properties. This document provides details of the design and execution of testing as well as an analysis of data for five new wells: R-9i, R-13, R-19, R-22, and R-31. One well (R-13) was evaluated by a pumping test and the rest (R-9i, R-19, R-22, and R-31) were evaluated by injection tests. Characterization well R-9i is located in Los Alamos Canyon approximately 0.3 mi west of the Route 4/Route 502 intersection. It was completed at a depth of 322 ft below ground surface (bgs) in March 2000. This well was constructed with two screens positioned below the regional water table. Both screens were tested. Screen 1 is completed at about 189-200 ft bgs in fractured basalt, and screen 2 is completed at about 270-280 ft bgs in massive basalt. Specific capacity analysis of the screen 1 data suggests that the fractured …
Date: June 1, 2004
Creator: S.G.McLin & Stone, W.J.
Object Type: Report
System: The UNT Digital Library
Proposed Strategies for DWPF Melter Off-Gas Surge Control (open access)

Proposed Strategies for DWPF Melter Off-Gas Surge Control

Off-gas surging is inherent to the operation of slurry-fed melters. Although the melter design and the feed chemistry are both known to significantly affect off-gas surging, the frequency and intensity of surges are in essence unpredictable. In typical off-gas surges, both condensable and non condensable flows spike simultaneously. Condensable or steam surges have been observed to occur as the boiling water layer occasionally falls into the crevices of the cold cap or flows over the edges of the cold cap, thereby coming in contact with the melt surface. The resulting steam surges can pressurize the melter considerably and, therefore, are responsible for the bulk of pressure transients that propagate throughout the off-gas system. The non condensable surges occur as the calcine gases that have been accumulating within the cold cap finally build up enough pressure to be released through the temporary openings of the cold cap. The analysis of off-gas data has shown that over 90 of the gas released during a surge is due to steam.1 Therefore, it is essential to have a large inventory of water in the cold cap for any significant pressure spikes to occur. With the Melter 2 vapor space temperature typically running at 720C, …
Date: June 1, 2004
Creator: CHOI, ALEXANDERS.
Object Type: Report
System: The UNT Digital Library
Development of Simulants to Support Mixing Tests for High Level Waste and Low Activity Waste (open access)

Development of Simulants to Support Mixing Tests for High Level Waste and Low Activity Waste

The objectives of this study were to develop two different types of simulants to support vendor agitator design studies and mixing studies. The initial simulant development task was to develop rheologically-bounding physical simulants and the final portion was to develop a nominal chemical simulant which is designed to match, as closely as possible, the actual sludge from a tank. The physical simulants to be developed included a lower and upper rheologically bounded: pretreated low activity waste (LAW) physical simulant; LAW melter feed physical simulant; pretreated high level waste (HLW) physical simulant; HLW melter feed physical simulant. The nominal chemical simulant, hereafter referred to as the HLW Precipitated Hydroxide simulant, is designed to represent the chemical/physical composition of the actual washed and leached sludge sample. The objective was to produce a simulant which matches not only the chemical composition but also the physical properties of the actual waste sample. The HLW Precipitated Hydroxide simulant could then be used for mixing tests to validate mixing, homogeneity and representative sampling and transferring issues. The HLW Precipitated Hydroxide simulant may also be used for integrated nonradioactive testing of the WTP prior to radioactive operation.
Date: June 1, 2004
Creator: EIBLING, RUSSELLE.
Object Type: Report
System: The UNT Digital Library
Big Sky Carbon Sequestration Partnership Quarterly Report (open access)

Big Sky Carbon Sequestration Partnership Quarterly Report

The Big Sky Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts during the second performance period fall into four areas: evaluation of sources and carbon sequestration sinks; development of GIS-based reporting framework; designing an integrated suite of monitoring, measuring, and verification technologies; and initiating a comprehensive education and outreach program. At the first two Partnership meetings the groundwork was put in place to provide an assessment of capture and storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research. The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the …
Date: June 1, 2004
Creator: Capalbo, Susan M.
Object Type: Report
System: The UNT Digital Library
Corrective Action Investigation Plan for Corrective Action Unit 151: Septic Systems and Discharge Area, Nevada Test Site, Nevada, Rev. No.: 0 (open access)

Corrective Action Investigation Plan for Corrective Action Unit 151: Septic Systems and Discharge Area, Nevada Test Site, Nevada, Rev. No.: 0

This Corrective Action Investigation Plan (CAIP) contains project-specific information for conducting site investigation activities at Corrective Action Unit (CAU) 151: Septic Systems and Discharge Area, Nevada Test Site, Nevada. Information presented in this CAIP includes facility descriptions, environmental sample collection objectives, and criteria for the selection and evaluation of environmental corrective action alternatives. Corrective Action Unit 151 is located in Areas 2, 12, 18, and 20 of the Nevada Test Site, which is 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit 151 is comprised of the nine Corrective Action Sites (CAS) listed below: (1) 02-05-01, UE-2ce Pond; (2) 12-03-01, Sewage Lagoons (6); (3) 12-04-01, Septic Tanks; (4) 12-04-02, Septic Tanks; (5) 12-04-03, Septic Tank; (6) 12-47-01, Wastewater Pond; (7) 18-03-01, Sewage Lagoon; (8) 18-99-09, Sewer Line (Exposed); and (9) 20-19-02, Photochemical Drain. The CASs within CAU 151 are discharge and collection systems. Corrective Action Site 02-05-01 is located in Area 2 and is a well-water collection pond used as a part of the Nash test. Corrective Action Sites 12-03-01, 12-04-01, 12-04-02, 12-04-03, and 12-47-01 are located in Area 12 and are comprised of sewage lagoons, septic tanks, associated piping, and two sumps. The features are a part of …
Date: June 1, 2004
Creator: Strand, David A.
Object Type: Report
System: The UNT Digital Library
Complete mitochondrial genome sequence of Urechis caupo, a representative of the phylum Echiura (open access)

Complete mitochondrial genome sequence of Urechis caupo, a representative of the phylum Echiura

None
Date: June 1, 2004
Creator: Boore, Jeffrey L.
Object Type: Article
System: The UNT Digital Library
Summary of human responses to ventilation (open access)

Summary of human responses to ventilation

The effects of ventilation on indoor air quality and health is a complex issue. It is known that ventilation is necessary to remove indoor generated pollutants from indoor air or dilute their concentration to acceptable levels. But, as the limit values of all pollutants are not known, the exact determination of required ventilation rates based on pollutant concentrations and associated risks is seldom possible. The selection of ventilation rates has to be based also on epidemiological research (e.g. Seppanen et al., 1999), laboratory and field experiments (e.g. CEN 1996, Wargocki et al., 2002a) and experience (e.g. ECA 2003). Ventilation may also have harmful effects on indoor air quality and climate if not properly designed, installed, maintained and operated as summarized by Seppdnen (2003). Ventilation may bring indoors harmful substances that deteriorate the indoor environment. Ventilation also affects air and moisture flow through the building envelope and may lead to moisture problems that deteriorate the structures of the building. Ventilation changes the pressure differences over the structures of building and may cause or prevent the infiltration of pollutants from structures or adjacent spaces. Ventilation is also in many cases used to control the thermal environment or humidity in buildings. Ventilation can …
Date: June 1, 2004
Creator: Seppanen, Olli A. & Fisk, William J.
Object Type: Article
System: The UNT Digital Library
Multiphase flow in complex fracture apertures under a wide range of flow conditions (open access)

Multiphase flow in complex fracture apertures under a wide range of flow conditions

The primary purpose of this project is to use a combination of computer modeling and laboratory experiments to obtain a better understanding of multiphase flow in geometrically complex fracture apertures under a wide range of flow conditions. Because traditional grid-based numerical methods perform poorly for multiphase flows with complex dynamic interfaces due to problems such as artificial interface broadening and grid entanglement, the modeling component of the program relies heavily on particle based methods. In particle-based models, the fluid-fluid interfaces move as the particles representing the fluids move--there is no need for explicit interface tracking, and no artificial front broadening. In addition, particle-based methods rigorously conserve mass because each particle represents a fixed mass of fluid and the number of particles does not change unless particles leave or enter the computational domain (to represent fluid flow into or out of the system). Because different model approaches have characteristic strengths and weaknesses, three different classes of particle-based models (lattice Boltzmann, dissipative particle dynamics and smoothed particle hydrodynamics) are being employed in this program. This will allow us to achieve our objective of simulating multiphase/multicomponent flow under a wide range of flow conditions for a wide range of fluid properties.
Date: June 1, 2004
Creator: Meakin, Paul; McCreery, Glenn E. & McEligot, Donald M.
Object Type: Report
System: The UNT Digital Library
TULSA UNIVERSITY PARAFFIN DEPOSITION PROJECTS (open access)

TULSA UNIVERSITY PARAFFIN DEPOSITION PROJECTS

As oil and gas production moves to deeper and colder water, subsea multiphase production systems become critical for economic feasibility. It will also become increasingly imperative to adequately identify the conditions for paraffin precipitation and predict paraffin deposition rates to optimize the design and operation of these multi-phase production systems. Although several oil companies have paraffin deposition predictive capabilities for single-phase oil flow, these predictive capabilities are not suitable for the multiphase flow conditions encountered in most flowlines and wellbores. For deepwater applications in the Gulf of Mexico, it is likely that multiphase production streams consisting of crude oil, produced water and gas will be transported in a single multiphase pipeline to minimize capital cost and complexity at the mudline. Existing single-phase (crude oil) paraffin deposition predictive tools are clearly inadequate to accurately design these pipelines, because they do not account for the second and third phases, namely, produced water and gas. The objective of this program is to utilize the current test facilities at The University of Tulsa, as well as member company expertise, to accomplish the following: enhance our understanding of paraffin deposition in single and two-phase (gas-oil) flows; conduct focused experiments to better understand various aspects of …
Date: June 1, 2004
Creator: Sarica, Cem & Volk, Michael
Object Type: Report
System: The UNT Digital Library
Remote Manipulation for D&D Exhibiting Teleautonomy and Telecollaboration (open access)

Remote Manipulation for D&D Exhibiting Teleautonomy and Telecollaboration

The purpose of the work is to enhance remote operations of robotic systems for D&D tasks by extending teleoperation with semi-autonomous functions. The work leverages the $1.2M dual-arm work platform (DAWP) developed with broad participation for the CP5 D&D, as well as 2,000 hr DAWP D&D operational experience. We propose to develop a reactive, agent-based control architecture well suited to unstructured and unpredictable environments, and robot control technology, which implements a virtual fixture that can be used to guide the application of tools with force-feedback control. Developed methodologies will be implemented using a structured light sensor and robot hand controller on the dual-arm system.
Date: June 1, 2004
Creator: Ewing, Thomas F.; Colgate, J. Edward; Park, Young S. & Peshkin, Michael A.
Object Type: Report
System: The UNT Digital Library
Hybrid Sulfur Recovery Process for Natural Gas Upgrading Quarterly Report (open access)

Hybrid Sulfur Recovery Process for Natural Gas Upgrading Quarterly Report

This final report describes the objectives, technical approach, results and conclusions for a project funded by the U.S. Department of Energy to test a hybrid sulfur recovery process for natural gas upgrading. The process concept is a configuration of CrystaTech, Inc.'s CrystaSulf{reg_sign} process which utilizes a direct oxidation catalyst upstream of the absorber tower to oxidize a portion of the inlet hydrogen sulfide (H{sub 2}S) to sulfur dioxide (SO{sub 2}) and elemental sulfur. This hybrid configuration of CrystaSulf has been named CrystaSulf-DO and represents a low-cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day and more. This hybrid process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both onshore and offshore applications. CrystaSulf is a nonaqueous sulfur recovery process that removes H{sub 2}S from gas streams and converts it to elemental sulfur. In CrystaSulf, H{sub 2}S in the inlet gas is reacted with SO{sub 2} to make elemental sulfur according to the liquid phase Claus reaction: 2H{sub 2}S + SO{sub …
Date: June 1, 2004
Creator: Dalrymple, Dennis
Object Type: Report
System: The UNT Digital Library
Concordant lipoprotein and weight responses to dietary fat changein identical twins with divergent exercise levels (open access)

Concordant lipoprotein and weight responses to dietary fat changein identical twins with divergent exercise levels

Background/Objective: The purpose of this study is to testthe extent that individual lipoprotein responses to diet can beattributed to genes in the presence of divergent exercise levels.Design:Twenty-eight pairs of male monozygotic twins (one mostly sedentary, theother running an average of 50 km/week more than the sedentary twin) wentfrom a 6-week 40 percent fat diet to a 6-week 20 percent fat diet in acrossover design. The diets reduced fat primarily by reducing saturatedand polyunsaturated fat (both from 14 percent to 4 percent), whileincreasing carbohydrate intake from 45 percent to 65 percent. Results:Despite the twins' differences in physical activity, the dietarymanipulation produced significantly correlated changes (P<0.05) in thetwin's total cholesterol (r=0.56), low-density lipoprotein(LDL)-cholesterol (r=0.70), large, buoyant LDL (Sf7-12, r=0.52), apo A-I(r=0.49), Lp(a) (r=0.49), electrophoresis measurements of LDL-I (LDLsbetween 26 and 28.5 nm diameter, r=0.48), LDL-IIB (25.2-24.6 nm, r=0.54),LDL-IV (22-24.1 nm, r=0.50), and body weights (r=0.41). Replacing fatswith carbohydrates significantly decreased the size and ultracentrifugeflotation rate of the major LDL, the LDL mass concentrations of Sf7-12,LDL-I, high-density lipoprotein (HDL)-cholesterol and apo A-I, andsignificantly increased LDL-IIIA (24.7-25.5 nm diameter) and Lp(a).Conclusions: Even in the presence of extreme exercise difference, genessignificantly affect changes in LDL, apo A-I, Lp(a) and body weight whendietary fats are replaced …
Date: June 1, 2004
Creator: Williams, Paul T.; Blanche, Patricia J.; Rawlings, Robin & Krauss, Ronald M.
Object Type: Article
System: The UNT Digital Library