Genomic Prospecting for Microbial Biodiesel Production (open access)

Genomic Prospecting for Microbial Biodiesel Production

Biodiesel is defined as fatty acid mono-alkylesters and is produced from triacylglycerols. In the current article we provide an overview of the structure, diversity and regulation of the metabolic pathways leading to intracellular fatty acid and triacylglycerol accumulation in three types of organisms (bacteria, algae and fungi) of potential biotechnological interest and discuss possible intervention points to increase the cellular lipid content. The key steps that regulate carbon allocation and distribution in lipids include the formation of malonyl-CoA, the synthesis of fatty acids and their attachment onto the glycerol backbone, and the formation of triacylglycerols. The lipid biosynthetic genes and pathways are largely known for select model organisms. Comparative genomics allows the examination of these pathways in organisms of biotechnological interest and reveals the evolution of divergent and yet uncharacterized regulatory mechanisms. Utilization of microbial systems for triacylglycerol and fatty acid production is in its infancy; however, genomic information and technologies combined with synthetic biology concepts provide the opportunity to further exploit microbes for the competitive production of biodiesel.
Date: March 20, 2008
Creator: Lykidis, Athanasios; Lykidis, Athanasios & Ivanova, Natalia
System: The UNT Digital Library
Collective phenomena in non-central nuclear collisions (open access)

Collective phenomena in non-central nuclear collisions

Recent developments in the field of anisotropic flow in nuclear collision are reviewed. The results from the top AGS energy to the top RHIC energy are discussed with emphasis on techniques, interpretation, and uncertainties in the measurements.
Date: October 20, 2008
Creator: Voloshin, Sergei A.; Poskanzer, Arthur M. & Snellings, Raimond
System: The UNT Digital Library
TOXNET and Beyond: Using the National Library of Medicine's Environmental Health and Toxicology Portal (open access)

TOXNET and Beyond: Using the National Library of Medicine's Environmental Health and Toxicology Portal

The National Library of Medicine's Environmental Health and Toxicology Portal provides access to numerous databases that can help you explore environmental chemicals and risks. TOXNET and Beyond: Using NLM's Environmental Health and Toxicology Portal conveys the fundamentals of searching the NLM's TOXNET system of databases in chemistry, toxicology, environmental health, and related fields. In addition to TOXNET, the course will highlight various resources available through the Environmental Health and Toxicology Portal.
Date: October 20, 2010
Creator: Templin-Branner, W.
System: The UNT Digital Library
Benefits of Parallel I/O in Ab Initio Nuclear Physics Calculations, ICCS 2009 Proceedings (open access)

Benefits of Parallel I/O in Ab Initio Nuclear Physics Calculations, ICCS 2009 Proceedings

Many modern scientific applications rely on highly parallel calculations, which scale to 10's of thousands processors. However, most applications do not concentrate on parallelizing input/output operations. In particular, sequential I/O has been identified as a bottleneck for the highly scalable MFDn (Many Fermion Dynamics for nuclear structure) code performing ab initio nuclear structure calculations. In this paper, we develop interfaces and parallel I/O procedures to use a well-known parallel I/O library in MFDn. As a result, we gain efficient input/output of large datasets along with their portability and ease of use in the downstream processing.
Date: May 20, 2009
Creator: Laghave, Nikhil; Sosonkina, Masha; Maris, Pieter & Vary, James P.
System: The UNT Digital Library
Electronic Structure Calculations and Adaptation Scheme in Multi-core Computing Environments (open access)

Electronic Structure Calculations and Adaptation Scheme in Multi-core Computing Environments

Multi-core processing environments have become the norm in the generic computing environment and are being considered for adding an extra dimension to the execution of any application. The T2 Niagara processor is a very unique environment where it consists of eight cores having a capability of running eight threads simultaneously in each of the cores. Applications like General Atomic and Molecular Electronic Structure (GAMESS), used for ab-initio molecular quantum chemistry calculations, can be good indicators of the performance of such machines and would be a guideline for both hardware designers and application programmers. In this paper we try to benchmark the GAMESS performance on a T2 Niagara processor for a couple of molecules. We also show the suitability of using a middleware based adaptation algorithm on GAMESS on such a multi-core environment.
Date: May 20, 2009
Creator: Seshagiri, Lakshminarasimhan; Sosonkina, Masha & Zhang, Zhao
System: The UNT Digital Library
CHAPTER 7. BERYLLIUM ANALYSIS BY NON-PLASMA BASED METHODS (open access)

CHAPTER 7. BERYLLIUM ANALYSIS BY NON-PLASMA BASED METHODS

The most common method of analysis for beryllium is inductively coupled plasma atomic emission spectrometry (ICP-AES). This method, along with inductively coupled plasma mass spectrometry (ICP-MS), is discussed in Chapter 6. However, other methods exist and have been used for different applications. These methods include spectroscopic, chromatographic, colorimetric, and electrochemical. This chapter provides an overview of beryllium analysis methods other than plasma spectrometry (inductively coupled plasma atomic emission spectrometry or mass spectrometry). The basic methods, detection limits and interferences are described. Specific applications from the literature are also presented.
Date: April 20, 2009
Creator: Ekechukwu, A
System: The UNT Digital Library
Clean Cities Award Winning Coalition: Salt Lake City (open access)

Clean Cities Award Winning Coalition: Salt Lake City

Since its designation as a national Clean City in 1994, Salt Lake Clean Cities has put more than 2,600 alternative fuel vehicles (AFVs) on community streets. The 82 business, nonprofit, and government agencies that comprise the coalition are all dedicated to cleaning the air by reducing vehicle exhaust. Salt Lake Clean Cities has the third largest compressed natural gas and propane-refueling infrastructure in the country, with 98 locations available. They sponsor an annual ''Spring Soiree'' to increase public awareness about the program and educate the public about the benefits of alternative fuel and AFVs.
Date: May 20, 1999
Creator: Kaiser, ICF
System: The UNT Digital Library
Clean Cities Award Winning Coalition: Greater Long Island (open access)

Clean Cities Award Winning Coalition: Greater Long Island

This coalition was the culmination a two-year joint effort by Long Island Lighting Company and the Long Island Regional Planning Board. The group's first alternative fuel project was a single fill compressed natural gas station and a converted Chevrolet Caprice. Since then, the coalition has made steady progress in the alternative fuel and alternative fuel vehicle (AFV) market. They have over 400 AFVs and 21 fueling stations in their operating area. Thanks to strong partnerships with local public and private organizations, they've also passed some of the most progressive state tax incentive legislation for AFVs in the country.
Date: May 20, 1999
Creator: Kaiser, ICF
System: The UNT Digital Library
Clean Cities Award Winning Coalition: Coachella Valley (open access)

Clean Cities Award Winning Coalition: Coachella Valley

Southern California's Coachella Valley became a Clean Cities region in 1996. Since then, they've made great strides. SunLine Transit, the regional public transit provider, was the first transit provider to replace its entire fleet with compressed natural gas buses. They've also built the foundation for a nationally recognized model in the clean air movement, by partnering with Southern California Gas Company to install a refueling station and developing a curriculum for AFV maintenance with the College of the Desert. Today the valley is home to more than 275 AFVs and 15 refueling stations.
Date: May 20, 1999
Creator: Kaiser, ICF
System: The UNT Digital Library
Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research (open access)

Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research

Scanning transmission x-ray microscopy (STXM) combines x-ray microscopy and near edge x-ray absorption fine structure spectroscopy (NEXAFS). This combination provides spatially resolved bonding and oxidation state information. While there are reviews relevant to STXM/NEXAFS applications in other environmental fields (and magnetic materials) this chapter focuses on atmospheric aerosols. It provides an introduction to this technique in a manner approachable to non-experts. It begins with relevant background information on synchrotron radiation sources and a description of NEXAFS spectroscopy. The bulk of the chapter provides a survey of STXM/NEXAFS aerosol studies and is organized according to the type of aerosol investigated. The purpose is to illustrate the current range and recent growth of scientific investigations employing STXM-NEXAFS to probe atmospheric aerosol morphology, surface coatings, mixing states, and atmospheric processing.
Date: January 20, 2011
Creator: Moffet, Ryan C.; Tivanski, Alexei V. & Gilles, Mary K.
System: The UNT Digital Library
Chapter 10: BlueGene/Q Sequoia and Mira (open access)

Chapter 10: BlueGene/Q Sequoia and Mira

None
Date: April 20, 2012
Creator: Vranas, P.
System: The UNT Digital Library
Storing Waste in Ceramic (open access)

Storing Waste in Ceramic

Not all the nuclear waste destined for Yucca Mountain is in the form of spent fuel. Some of it will be radioactive waste generated from the production of nuclear weapons. This so-called defense waste exists mainly as corrosive liquids and sludge in underground tanks. An essential task of the U.S. high-level radioactive waste program is to process these defense wastes into a solid material--called a waste form. An ideal waste form would be extremely durable and unreactive with other repository materials. It would be simple to fabricate remotely so that it could be safely transported to a repository for permanent storage. What's more, the material should be able to tolerate exposure to intense radiation without degradation. And to minimize waste volume, the material must be able to contain high concentrations of radionuclides. The material most likely to be used for immobilization of radioactive waste is glass. Glasses are produced by rapid cooling of high-temperature liquids such that the liquid-like non-periodic structure is preserved at lower temperatures. This rapid cooling does not allow enough time for thermodynamically stable crystalline phases (mineral species) to form. In spite of their thermodynamic instability, glasses can persist for millions of years. An alternate to glass …
Date: July 20, 2004
Creator: Bourcier, W. L. & Sickafus, K.
System: The UNT Digital Library
Clean Cities Award Winning Coalition: Greater Philadelphia (open access)

Clean Cities Award Winning Coalition: Greater Philadelphia

Always going beyond expectations, the Greater Philadelphia Clean Cities Program provides its stakeholders with excellent resources to implement alternative fuel projects. They are known as one of the most successful coalitions in the Clean Cities Program, and are a member-funded organization comprised of large government organizations, utilities, and non-profit groups in the Philadelphia metropolitan area. The coalition aggressively promotes alternative fuel vehicle acquisitions; their public outreach efforts target all stakeholders and provide numerous resources to advance the alternative fuel choice.
Date: May 20, 1999
Creator: Kaiser, ICF
System: The UNT Digital Library
NREL PV working with industry, 1st Quarter 1999 (open access)

NREL PV working with industry, 1st Quarter 1999

This issue of PV Working with Industry profiles the participants in the Photovoltaic Manufacturing Technology (PVMaT) project.
Date: May 20, 1999
Creator: Moon, S.
System: The UNT Digital Library
A quick guide to solar electricity (open access)

A quick guide to solar electricity

A small brochure about solar electricity for the general public to be handed out on Earth Day 2000.
Date: March 20, 2000
Creator: Poole, L.
System: The UNT Digital Library
Advanced Technology and Alternative Fuel Vehicles (open access)

Advanced Technology and Alternative Fuel Vehicles

This fact sheet provides a basic overview of today's alternative fuel choices--including biofuels, biodiesel, electricity, and hydrogen--alternative fuel vehicles, and advanced vehicle technology, such as hybrid electric vehicles, fuel cells and advanced drive trains.
Date: August 20, 2001
Creator: Tuttle, J.
System: The UNT Digital Library
Providing Energy Efficiency and Cost Savings for U.S. Industry: Industries of the Future BestPractices Fact Sheet (open access)

Providing Energy Efficiency and Cost Savings for U.S. Industry: Industries of the Future BestPractices Fact Sheet

This 2-page fact sheet describes the Office of Industrial Technologies BestPractices program activities and services.
Date: September 20, 2000
Creator: unknown
System: The UNT Digital Library
Forest Products -- Industry of the Future (open access)

Forest Products -- Industry of the Future

This 8-page brochure describes the partnership between the forest products industry and DOE's Office of Industrial Technologies. It highlights the benefits to industry of working with the Forest Products Industry of the Future Team to reduce energy consumption and lower costs.
Date: November 20, 2000
Creator: unknown
System: The UNT Digital Library
Alternative Fuel News, Vol. 2, No. 7 (open access)

Alternative Fuel News, Vol. 2, No. 7

What's in store for alternative Fuels and advanced technology vehicles in the new millennium? The Clean Cities Coalitions now operate more than 240,000 alternative fuel vehicles in both public and private sectors and have access to more than 4,000 alternative refueling stations. DOE recently announced the selection of 15 proposals that will receive just under $1.7 million in financial assistance to help expand DOE's information dissemination and public outreach efforts for alternative fuels and advanced transportation technologies.
Date: May 20, 1999
Creator: National Renewable Energy Laboratory (U.S.)
System: The UNT Digital Library
Technology Cooperation Agreement Pilot Project (TCAPP) (open access)

Technology Cooperation Agreement Pilot Project (TCAPP)

The Technology Cooperation Agreement Pilot Project (TCAPP) is helping developing countries design and implement actions to attract investment in clean energy technologies that will meet their economic development goals, while mitigating greenhouse gas emissions. TCAPP was launched by three US government agencies -- the US Agency for International Development (USAID), the US Environmental Protection Agency (USEPA), and the US Department of Energy (USDOE) -- in August 1997 to establish a model for climate change technology cooperation with developing and transition countries. This report describes the TCAPP approach and the significant progress made by the participating countries.
Date: October 20, 1999
Creator: Keegan, P. & Benioff, R.
System: The UNT Digital Library
Models of Superoxide Dismutases (open access)

Models of Superoxide Dismutases

In this review we have focused much of our discussion on the mechanistic details of how the native enzymes function and how mechanistic developments/insights with synthetic small molecule complexes possessing SOD activity have influenced our understanding of the electron transfer processes involved with the natural enzymes. A few overriding themes have emerged. Clearly, the SOD enzymes operate at near diffusion controlled rates and to achieve such catalytic turnover activity, several important physical principles must be operative. Such fast electron transfer processes requires a role for protons; i.e., proton-coupled electron transfer (''H-atom transfer'') solves the dilemma of charge separation developing in the transition state for the electron transfer step. Additionally, outer-sphere electron transfer is likely a most important pathway for manganese and iron dismutases. This situation arises because the ligand exchange rates on these two ions in water never exceed {approx}10{sup +7} s{sup -1}; consequently, 10{sup +9} catalytic rates require more subtle mechanistic insights. In contrast, copper complexes can achieve diffusion controlled (>10{sup +9}) exchange rates in water; thus inner-sphere electron transfer processes are more likely to be operative in the Cu/Zn enzymes. Recent studies have continued to expand our understanding of the mechanism of action of this most important class …
Date: May 20, 1998
Creator: Cabelli, Diane E.; Riley, Dennis; Rodriguez, Jorge A.; Valentine, Joan Selverstone & Zhu, Haining
System: The UNT Digital Library
Financing an Energy-Efficient Home: Energy Efficiency and Renewable Energy Clearinghouse (EREC) Fact Sheet (open access)

Financing an Energy-Efficient Home: Energy Efficiency and Renewable Energy Clearinghouse (EREC) Fact Sheet

This report is a fact sheet that explains the basics of energy-efficient home financing.
Date: September 20, 2000
Creator: Waggoner, T.
System: The UNT Digital Library
Department of Energy's Pantex Plant Saves $10 Million in Energy Costs. Federal Energy Management Program (FEMP) ESPC Case Study Fact Sheet (open access)

Department of Energy's Pantex Plant Saves $10 Million in Energy Costs. Federal Energy Management Program (FEMP) ESPC Case Study Fact Sheet

This two-page case study describes how the U.S. Department of Energy's Pantex Plant in Amarillo, Texas, will save approximately $10 million in energy costs over the next 18 years, thanks to a DOE Super Energy Savings Performance Contract (Super ESPC) delivery order for energy efficiency improvements. The delivery order is the largest to date for a DOE facility. Primarily, the delivery order calls for a new, state-of-the-art energy management control system and a new water/steam piping system, which will be purchased and installed by the contracting energy services company (ESCO). The ESCO will then be repaid over the life of the contract out of the plant's resulting energy cost savings.
Date: November 20, 2001
Creator: Ward, C.
System: The UNT Digital Library
Hydrogen Outgassing from Lithium Hydride (open access)

Hydrogen Outgassing from Lithium Hydride

Lithium hydride is a nuclear material with a great affinity for moisture. As a result of exposure to water vapor during machining, transportation, storage and assembly, a corrosion layer (oxide and/or hydroxide) always forms on the surface of lithium hydride resulting in the release of hydrogen gas. Thermodynamically, lithium hydride, lithium oxide and lithium hydroxide are all stable. However, lithium hydroxides formed near the lithium hydride substrate (interface hydroxide) and near the sample/vacuum interface (surface hydroxide) are much less thermally stable than their bulk counterpart. In a dry environment, the interface/surface hydroxides slowly degenerate over many years/decades at room temperature into lithium oxide, releasing water vapor and ultimately hydrogen gas through reaction of the water vapor with the lithium hydride substrate. This outgassing can potentially cause metal hydriding and/or compatibility issues elsewhere in the device. In this chapter, the morphology and the chemistry of the corrosion layer grown on lithium hydride (and in some cases, its isotopic cousin, lithium deuteride) as a result of exposure to moisture are investigated. The hydrogen outgassing processes associated with the formation and subsequent degeneration of this corrosion layer are described. Experimental techniques to measure the hydrogen outgassing kinetics from lithium hydride and methods employing …
Date: April 20, 2006
Creator: Dinh, L. N.; Schildbach, M. A.; Smith, R. A.; Balazs, B. & McLean, W., II
System: The UNT Digital Library