Cavity Microwave Searches for Cosmological Axions (open access)

Cavity Microwave Searches for Cosmological Axions

This chapter will cover the search for dark matter axions based on microwave cavity experiments proposed by Pierre Sikivie. We will start with a brief overview of halo dark matter and the axion as a candidate. The principle of resonant conversion of axions in an external magnetic field will be described as well as practical considerations in optimizing the experiment as a signal-to-noise problem. A major focus of this chapter will be the two complementary strategies for ultra-low noise detection of the microwave photons--the 'photon-as-wave' approach (i.e. conventional heterojunction amplifiers and soon to be quantum-limited SQUID devices), and 'photon-as-particle' (i.e. Rydberg-atom single-quantum detection). Experimental results will be presented; these experiments have already reached well into the range of sensitivity to exclude plausible axion models, for limited ranges of mass. The section will conclude with a discussion of future plans and challenges for the microwave cavity experiment.
Date: January 22, 2007
Creator: Carosi, G. & van Bibber, K.
System: The UNT Digital Library
Comparative assessment of status and opportunities for carbon Dioxide Capture and storage and Radioactive Waste Disposal In North America (open access)

Comparative assessment of status and opportunities for carbon Dioxide Capture and storage and Radioactive Waste Disposal In North America

Aside from the target storage regions being underground, geologic carbon sequestration (GCS) and radioactive waste disposal (RWD) share little in common in North America. The large volume of carbon dioxide (CO{sub 2}) needed to be sequestered along with its relatively benign health effects present a sharp contrast to the limited volumes and hazardous nature of high-level radioactive waste (RW). There is well-documented capacity in North America for 100 years or more of sequestration of CO{sub 2} from coal-fired power plants. Aside from economics, the challenges of GCS include lack of fully established legal and regulatory framework for ownership of injected CO{sub 2}, the need for an expanded pipeline infrastructure, and public acceptance of the technology. As for RW, the USA had proposed the unsaturated tuffs of Yucca Mountain, Nevada, as the region's first high-level RWD site before removing it from consideration in early 2009. The Canadian RW program is currently evolving with options that range from geologic disposal to both decentralized and centralized permanent storage in surface facilities. Both the USA and Canada have established legal and regulatory frameworks for RWD. The most challenging technical issue for RWD is the need to predict repository performance on extremely long time scales …
Date: July 22, 2011
Creator: Oldenburg, C. & Birkholzer, J.T.
System: The UNT Digital Library
Susceptibility to Exposure to Heterocyclic Amines from Cooked Food: Role of UDP-glucuronosyltransferases (open access)

Susceptibility to Exposure to Heterocyclic Amines from Cooked Food: Role of UDP-glucuronosyltransferases

A number of carcinogenic heterocyclic amines (PhIP, MeIQx, and DiMeIQx) are produced from the condensation of creatinine, hexoses and amino acids during the cooking of meat (1). There are many variables that impact the production and subsequent ingestion of these compounds in our diet. Temperature, type of meat product, cooking method, doneness, and other factors affect the quantity of these carcinogens consumed by humans. Estimates of ingestion of these carcinogens are 1-20 ng/kg body weight per day (2). Human case control studies that correlate meat consumption from well-done cooking practices with cancer incidence indicate excess tumors for breast, colon, stomach, esophagus, and possibly prostate (3-5).
Date: August 22, 2005
Creator: Malfatti, M. A. & Felton, J. S.
System: The UNT Digital Library
RECENT ADVANCES IN THE DEVELOPMENT OF THE HYBRID SULFUR PROCESS FOR HYDROGEN PRODUCTION (open access)

RECENT ADVANCES IN THE DEVELOPMENT OF THE HYBRID SULFUR PROCESS FOR HYDROGEN PRODUCTION

Thermochemical processes are being developed to provide global-scale quantities of hydrogen. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process, which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce the hydrogen. In the HyS Process, sulfur dioxide is oxidized in the presence of water at the electrolyzer anode to produce sulfuric acid and protons. The protons are transported through a cation-exchange membrane electrolyte to the cathode and are reduced to form hydrogen. In the second stage of the process, the sulfuric acid by-product from the electrolyzer is thermally decomposed at high temperature to produce sulfur dioxide and oxygen. The two gases are separated and the sulfur dioxide recycled to the electrolyzer for oxidation. The Savannah River National Laboratory (SRNL) has been exploring a fuel-cell design concept for the SDE using an anolyte feed comprised of concentrated sulfuric acid saturated with sulfur dioxide. The advantages of this design concept include high electrochemical efficiency and small footprint compared to a parallel-plate electrolyzer design. This paper will provide a summary of recent advances in the development of the SDE for the HyS process.
Date: July 22, 2010
Creator: Hobbs, D.
System: The UNT Digital Library
Sequencing and comparing whole mitochondrial genomes ofanimals (open access)

Sequencing and comparing whole mitochondrial genomes ofanimals

Comparing complete animal mitochondrial genome sequences is becoming increasingly common for phylogenetic reconstruction and as a model for genome evolution. Not only are they much more informative than shorter sequences of individual genes for inferring evolutionary relatedness, but these data also provide sets of genome-level characters, such as the relative arrangements of genes, that can be especially powerful. We describe here the protocols commonly used for physically isolating mtDNA, for amplifying these by PCR or RCA, for cloning,sequencing, assembly, validation, and gene annotation, and for comparing both sequences and gene arrangements. On several topics, we offer general observations based on our experiences to date with determining and comparing complete mtDNA sequences.
Date: April 22, 2005
Creator: Boore, Jeffrey L.; Macey, J. Robert & Medina, Monica
System: The UNT Digital Library
ELECTRONS IN NONPOLAR LIQUIDS. (open access)

ELECTRONS IN NONPOLAR LIQUIDS.

Excess electrons can be introduced into liquids by absorption of high energy radiation, by photoionization, or by photoinjection from metal surfaces. The electron's chemical and physical properties can then be measured, but this requires that the electrons remain free. That is, the liquid must be sufficiently free of electron attaching impurities for these studies. The drift mobility as well as other transport properties of the electron are discussed here as well as electron reactions, free-ion yields and energy levels, Ionization processes typically produce electrons with excess kinetic energy. In liquids during thermalization, where this excess energy is lost to bath molecules, the electrons travel some distance from their geminate positive ions. In general the electrons at this point are still within the coulombic field of their geminate ions and a large fraction of the electrons recombine. However, some electrons escape recombination and the yield that escapes to become free electrons and ions is termed G{sub fi}. Reported values of G{sub fi} for molecular liquids range from 0.05 to 1.1 per 100 eV of energy absorbed. The reasons for this 20-fold range of yields are discussed here.
Date: October 22, 2002
Creator: Holroyd, R. A.
System: The UNT Digital Library
Energy Matters - September/October 2000 issue (open access)

Energy Matters - September/October 2000 issue

This is a bimonthly newsletter from DOE's Office of Industrial Technologies to promote the use of energy-efficient industrial systems.
Date: September 22, 2000
Creator: Mallory, M.
System: The UNT Digital Library
Geothermal Energy Heat from the Earth: Nevada; GeoPowering the West Series Fact Sheet (Revised October 2001) (open access)

Geothermal Energy Heat from the Earth: Nevada; GeoPowering the West Series Fact Sheet (Revised October 2001)

General use fact sheet about geothermal energy in Nevada. Nevada holds the largest amount of untapped geothermal resources in the U.S., with a potential of 2,500 to 3,700 megawatts of electricity (Mwe).
Date: October 22, 2001
Creator: Boddy, S.
System: The UNT Digital Library
Guide to alternative fuel vehicle incentives and laws: September 1998 (open access)

Guide to alternative fuel vehicle incentives and laws: September 1998

This guide provides information in support of the National Clean Cities Program, which will assist one in becoming better informed about the choices and options surrounding the use of alternative fuels and the purchase of alternative fuel vehicles. The information printed in this guide is current as of September 15, 1998. For recent additions or more up-to-date information, check the Alternative Fuels Data Center Web site at http://www.afdc.doe.gov
Date: December 22, 1998
Creator: Riley, C. & O'Connor, K.
System: The UNT Digital Library
The technology roadmap for plant/crop-based renewable resources 2020 (open access)

The technology roadmap for plant/crop-based renewable resources 2020

The long-term well-being of the nation and maintenance of a sustainable leadership position in agriculture, forestry, and manufacturing, clearly depend on current and near-term support of multidisciplinary research for the development of a reliable renewable resource base. This document sets a roadmap and priorities for that research. America needs leadership that will continue to recognize, support, and move rapidly to meet the need to expand the use of sustainable renewable resources. This roadmap has highlighted potential ways for progress and has identified goals in specific components of the system. Achieving success with these goals will provide the opportunity to hit the vision target of a fivefold increase in renewable resource use by 2020.
Date: February 22, 1999
Creator: McLaren, J.
System: The UNT Digital Library
POLYETHYLENE ENCAPSULATION. (open access)

POLYETHYLENE ENCAPSULATION.

Polyethylene microencapsulation physically homogenizes and incorporates mixed waste particles within a molten polymer matrix, forming a solidified final waste form upon cooling. Each individual particle of waste is embedded within the polymer block and is surrounded by a durable, leach-resistant coating. The process has been successfully applied for the treatment of a broad range of mixed wastes, including evaporator concentrate salts, soil, sludges, incinerator ash, off-gas blowdown solutions, decontamination solutions, molten salt oxidation process residuals, ion exchange resins, granular activated carbon, shredded dry active waste, spill clean-up residuals, depleted uranium powders, and failed grout waste forms. For waste streams containing high concentrations of soluble toxic metal contaminants, additives can be used to further reduce leachability, thus improving waste loadings while meeting or exceeding regulatory disposal criteria. In this configuration, contaminants are both chemically stabilized and physically solidified, making the process a true stabilization/solidification (S/S) technology. Unlike conventional hydraulic cement grouts or thermosetting polymers, thermoplastic polymers such as polyethylene require no chemical. reaction for solidification. Thus, a stable, solid, final waste form product is assured on cooling. Variations in waste chemistry over time do not affect processing parameters and do not require reformulation of the recipe. Incorporation of waste particles within …
Date: August 22, 2001
Creator: Kalb, P.
System: The UNT Digital Library
FEMP: Showering with the sun at Chickasaw National Recreation Area case study (open access)

FEMP: Showering with the sun at Chickasaw National Recreation Area case study

This FEMP Technical Assistance Case Study describes the use of solar water heating at the Chickasaw National Recreation Area in Oklahoma. The solar systems are an environmentally sound and cost-effective way to heat water. By using renewable energy technologies to satisfy its mandate to provide services for visitors and protect the park system's natural resources, the National Park Service sets a good example for other Federal agencies and the general public.
Date: February 22, 1999
Creator: McIntyre, M.
System: The UNT Digital Library
Alternative Fuel News: Official Publication of the U.S. Department of Energy's Clean Cities Network and the Alternative Fuels Data Center; Vol. 4, No. 4 (open access)

Alternative Fuel News: Official Publication of the U.S. Department of Energy's Clean Cities Network and the Alternative Fuels Data Center; Vol. 4, No. 4

Alternative Fuel News, an ongoing quarterly publication for the U.S. Department of Energy. An official publication of the Clean Cities Network and the Alternative Fuels Data Center.
Date: February 22, 2001
Creator: Coulter, J. & Ficker, C.
System: The UNT Digital Library
OIT Tools Can Help You Improve Productivity: Office of Industrial Technologies (OIT) Industries of the Future BestPractices Tools and Information Fact Sheet (open access)

OIT Tools Can Help You Improve Productivity: Office of Industrial Technologies (OIT) Industries of the Future BestPractices Tools and Information Fact Sheet

This case study is the latest in a series on industrial firms who are implementing energy efficient technologies and system improvements into their manufacturing processes. The case studies document the activities, savings, and lessons learned on these projects.
Date: August 22, 2001
Creator: United States. Department of Energy.
System: The UNT Digital Library
Laboratories for the 21st Century: An Introduction to Low-Energy Design; Federal Energy Management Program (FEMP) Brochure (open access)

Laboratories for the 21st Century: An Introduction to Low-Energy Design; Federal Energy Management Program (FEMP) Brochure

With its extensive requirements for environmental systems, flexibility, and growth, energy-efficient laboratory design is a challenge. Unlike other building types, a laboratory has HVAC and energy considerations that cannot be deferred; they must play a key, formative role if the building is to succeed. This publication should help to sensitize building professionals and their clients to the complex array of issues associated with efficient laboratory design and performance. This is only an introduction and you will need to consult other resources for in-depth information about energy-efficient laboratory design.
Date: August 22, 2000
Creator: Prowler, D.
System: The UNT Digital Library
Plant-Wide Assessments Help Industry Identify Energy and Cost Savings Opportunities: Office of Industrial Technologies (OIT) Industries of the Future BestPractices Plant-Wide Assessments Fact Sheet (open access)

Plant-Wide Assessments Help Industry Identify Energy and Cost Savings Opportunities: Office of Industrial Technologies (OIT) Industries of the Future BestPractices Plant-Wide Assessments Fact Sheet

This case study is the latest in a series on industrial firms who are implementing energy efficient technologies and system improvements into their manufacturing processes. The case studies document the activities, savings, and lessons learned on these projects.
Date: August 22, 2001
Creator: United States. Department of Energy.
System: The UNT Digital Library
SULFUR POLYMER ENCAPSULATION. (open access)

SULFUR POLYMER ENCAPSULATION.

Sulfur polymer cement (SPC) is a thermoplastic polymer consisting of 95 wt% elemental sulfur and 5 wt% organic modifiers to enhance long-term durability. SPC was originally developed by the U.S. Bureau of Mines as an alternative to hydraulic cement for construction applications. Previous attempts to use elemental sulfur as a construction material in the chemical industry failed due to premature degradation. These failures were caused by the internal stresses that result from changes in crystalline structure upon cooling of the material. By reacting elemental sulfur with organic polymers, the Bureau of Mines developed a product that successfully suppresses the solid phase transition and significantly improves the stability of the product. SPC, originally named modified sulfur cement, is produced from readily available, inexpensive waste sulfur derived from desulfurization of both flue gases and petroleum. The commercial production of SPC is licensed in the United States by Martin Resources (Odessa, Texas) and is marketed under the trade name Chement 2000. It is sold in granular form and is relatively inexpensive ({approx}$0.10 to 0.12/lb). Application of SPC for the treatment of radioactive, hazardous, and mixed wastes was initially developed and patented by Brookhaven National Laboratory (BNL) in the mid-1980s (Kalb and Colombo, 1985; …
Date: August 22, 2001
Creator: Kalb, P.
System: The UNT Digital Library