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Colorado's clean energy choices (open access)

Colorado's clean energy choices

The daily choices made as consumers affect the environment and the economy. Based on the state of today's technology and economics, Colorado consumers can include energy efficiency and renewable energy into many aspects of their lives. These choices include where they obtain electricity, how they use energy at home, and how they transport themselves from one place to another. In addition to outlining how they can use clean energy, Colorado's Clean Energy Choices gives consumers contacts and links to Web sites for where to get more information.
Date: April 15, 2000
Creator: Strawn, N. & Jones, J.
Object Type: Book
System: The UNT Digital Library
Combined Heat and Power for Saving Energy and Carbon inResidential Buildings (open access)

Combined Heat and Power for Saving Energy and Carbon inResidential Buildings

This report is the description of saving carbon in residences using the microCHP.
Date: April 15, 2000
Creator: Kaarsberg, Tina; Fiskum, Ronald; Deppe, Andreas; Kumar, Satish; Rosenfeld, Arthur; Romm, Joseph et al.
Object Type: Article
System: The UNT Digital Library
Excess Weapons Plutonium Immobilization in Russia (open access)

Excess Weapons Plutonium Immobilization in Russia

The joint goal of the Russian work is to establish a full-scale plutonium immobilization facility at a Russian industrial site by 2005. To achieve this requires that the necessary engineering and technical basis be developed in these Russian projects and the needed Russian approvals be obtained to conduct industrial-scale immobilization of plutonium-containing materials at a Russian industrial site by the 2005 date. This meeting and future work will provide the basis for joint decisions. Supporting R&D projects are being carried out at Russian Institutes that directly support the technical needs of Russian industrial sites to immobilize plutonium-containing materials. Special R&D on plutonium materials is also being carried out to support excess weapons disposition in Russia and the US, including nonproliferation studies of plutonium recovery from immobilization forms and accelerated radiation damage studies of the US-specified plutonium ceramic for immobilizing plutonium. This intriguing and extraordinary cooperation on certain aspects of the weapons plutonium problem is now progressing well and much work with plutonium has been completed in the past two years. Because much excellent and unique scientific and engineering technical work has now been completed in Russia in many aspects of plutonium immobilization, this meeting in St. Petersburg was both timely …
Date: April 15, 2000
Creator: Jardine, L. & Borisov, G.B.
Object Type: Report
System: The UNT Digital Library
Innovative, new and advanced high voltage power supply for capacitor charging at linear collider. Final report (open access)

Innovative, new and advanced high voltage power supply for capacitor charging at linear collider. Final report

None
Date: April 15, 2000
Creator: Clanin, W.; Krichtafovitch, I.; White, D. & Gnehm, C.
Object Type: Report
System: The UNT Digital Library
Microbial ecology of thermophilic anaerobic digestion. Final report (open access)

Microbial ecology of thermophilic anaerobic digestion. Final report

This grant supported research on methanogenic archaea. The two major areas that were supported were conversion of acetic acid to methane and nitrogen fixation by Methanosarcina. Among the achievements of this research were the isolation of novel methanogenic cultures, elucidation of the pathways from acetate to methane, description of a specific DNA-binding complex in nitrogen fixing methanogens, and demonstration of an alternative nitrogenase in Methanosarcina.
Date: April 15, 2000
Creator: Zinder, Stephen H.
Object Type: Report
System: The UNT Digital Library
Annual Report 2000. Chemical Structure and Dynamics (open access)

Annual Report 2000. Chemical Structure and Dynamics

This annual report describes the research and accomplishments of the Chemical Structure and Dynamics Program in the year 2000, one of six research programs at the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) - a multidisciplinary, national scientific user facility and research organization. The Chemical Structure and Dynamics (CS&D) program is meeting the need for a fundamental, molecular-level understanding by 1) extending the experimental characterization and theoretical description of chemical reactions to encompass the effects of condensed media and interfaces; 2) developing a multidisciplinary capability for describing interfacial chemical processes relevant to environmental chemistry; and 3) developing state-of-the-art research and analytical methods for characterizing complex materials of the types found in natural and contaminated systems.
Date: April 15, 2001
Creator: Colson, Steven D. & McDowell, Robin S.
Object Type: Report
System: The UNT Digital Library
A Development of On-Line Temperature Measurement Instrumentation for Gasification Process Control Progress Report (open access)

A Development of On-Line Temperature Measurement Instrumentation for Gasification Process Control Progress Report

This progress report covers continuing work to develop a temperature probe for a coal gasifier. A workable probe design requires finding answers to crucial questions involving the probe materials. We report on attempts to answer those questions. We attempted to measure the laser-input power at a wavelength of 355 nm that would damage the ends of sapphire fiber optics. We were surprised and pleased to learn that they survived an input power density of about 3 x 10{sup 9} W/cm{sup 2}, which greatly exceeds the best that fused-silica fibers can do. During a run of our new simulator to obtain an upgraded calibration curve for the improved YAG:Dy phosphors, we found that the phosphor appeared to form a eutectic, with the fused-silica cuvette used to hold the phosphor, when the temperature exceeded 1450 C. This result could have substantial ramifications in this and other high-temperature applications. Our new proprietary detector package that replaced the original photomultiplier tube gave excellent results, with much better signal-to-noise ratio at a given temperature than the old package. Our new plasma-spraying operation has succeeded in spraying YAG, which we think may be a technological breakthrough.
Date: April 15, 2001
Creator: Noel, Bruce W.
Object Type: Report
System: The UNT Digital Library
Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report (open access)

Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report

In this quarter, the research effort is to develop the drill control unit (DCU) that acquire, store drilling parameters and control the drilling operation. The relevant publications have been reviewed and the methodology developed by previous researchers has been evaluated using the collected data in our laboratory and field tests conducted prior to the start of this project. Numerical modeling for exploring roof bolting mechanism has been started.
Date: April 15, 2001
Creator: Peng, Syd S.
Object Type: Report
System: The UNT Digital Library
MAPPING INDUCED POLARIZATION WITH NATURAL ELECTROMAGNETIC FIELDS FOR EXPLORATION AND RESOURCES CHARACTERIZATION BY THE MINING INDUSTRY (open access)

MAPPING INDUCED POLARIZATION WITH NATURAL ELECTROMAGNETIC FIELDS FOR EXPLORATION AND RESOURCES CHARACTERIZATION BY THE MINING INDUSTRY

In this first quarter we made an organizational change in the project that should allow us to more easily meet the project milestones. This change consists of designing a new systems that will allow to simplify field operation and reduce survey costs. The new system design has been completed and we are in the process of completing the manufacture and test of the first prototype. Production of the final system for the survey should be completed by end of July. The new acquisition and processing software is in progress and will be ready by the end of July. The new processing software will include the robust processing developed by Larsen and Egbert.
Date: April 15, 2001
Creator: Nichols, Edward
Object Type: Report
System: The UNT Digital Library
Structural aspects of the fivefold quasicrystalline Al-Cu-Fe surface from STM and dynamical LEED Studies (open access)

Structural aspects of the fivefold quasicrystalline Al-Cu-Fe surface from STM and dynamical LEED Studies

We investigate the atomic structure of the fivefold surface of an icosahedral Al-Cu-Fe alloy, using scanning tunneling microscopy (STM) imaging and a special dynamical low energy-electron diffraction (LEED) method. STM indicates that the step heights adopt (primarily) two values in the ratio of tau, but the spatial distribution of these two values does not follow a Fibonacci sequence, thus breaking the ideal bulk-like quasicrystalline layer stacking order perpendicular to the surface. The appearance of screw dislocations in the STM images is another indication of imperfect quasicrystallinity. On the other hand, the LEED analysis, which was successfully applied to Al-Pd-Mn in a previous study, is equally successful for Al-Cu-Fe. Similar structural features are found for both materials, in particular for interlayer relaxations and surface terminations. Although there is no structural periodicity, there are clear atomic planes in the bulk of the quasicrystal, some of which can be grouped in recurring patterns. The surface tends to form between these grouped layers in both alloys. For Al-Cu-Fe, the step heights measured by STM are consistent with the thicknesses of the grouped layers favored in LEED. These results suggest that the fivefold Al-Cu-Fe surface exhibits a quasicrystalline layering structure, but with stacking defects.
Date: April 15, 2001
Creator: Cai, T.; Shi, F.; Shen, Z.; Gierer, M.; Goldman, A. I.; Kramer, M. J. et al.
Object Type: Article
System: The UNT Digital Library
ULTRA-LIGHTWEIGHT CEMENT (open access)

ULTRA-LIGHTWEIGHT CEMENT

The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter.
Date: April 15, 2001
Creator: Sabins, Fred
Object Type: Report
System: The UNT Digital Library
Advances in Low-Defect Multilayers for EUVL Mask Blanks (open access)

Advances in Low-Defect Multilayers for EUVL Mask Blanks

Low-defect multilayer coatings are required to fabricate mask blanks for Extreme Ultraviolet Lithography (EUVL). The mask blanks consist of high reflectance E W multilayers on low thermal expansion substrates. A defect density of 0.0025 printable defects/cm{sup 2} for both the mask substrate and the multilayer is required to provide a mask blank yield of 60%. Current low defect multilayer coating technology allows repeated coating-added defect levels of 0.05/cm{sup 2} for defects greater than 90 nm polystyrene latex sphere (PSL) equivalent size for lots of 20 substrates. Extended clean operation of the coating system at levels below 0.08/cm{sup 2} for 3 months of operation has also been achieved. Two substrates with zero added defects in the quality area have been fabricated, providing an existence proof that ultra low defect coatings are possible. Increasing the ion source-to-target distance from 410 to 560 mm to reduce undesired coating of the ion source caused the defect density to increase to 0.2/cm{sup 2}. Deposition and etching diagnostic witness substrates and deposition pinhole cameras showed a much higher level of ion beam spillover (ions missing the sputter target) than expected. Future work will quantify beam spillover, and test designs to reduce spillover, if it is confirmed …
Date: April 15, 2002
Creator: Folta, J. A.; Davidson, J. C.; Larson, C. C.; Walton, C. C. & Kearney, P. A.
Object Type: Article
System: The UNT Digital Library
BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS (open access)

BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), and up to 5500 psi with emphasis upon 35 MPa (5000 psi) steam. In the 21st century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while at the same time preserving environmental values. Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios. The use of coal for electricity generation poses a unique set of challenges. On the one hand, coal is plentiful and available at low cost in much of the world, notably in the U.S., China, and India. Countries with large coal reserves will want to develop them to foster economic growth and energy security. On the other hand, traditional methods of coal combustion emit pollutants and CO{sub 2} at high levels relative to other generation options. Maintaining coal as a generation option in the 21st century will require methods for addressing these environmental …
Date: April 15, 2002
Creator: Viswanathan, R.
Object Type: Report
System: The UNT Digital Library
Design, operational experiences and beam results obtained with the SNS H- ion source and LEBT at Berkeley Lab (open access)

Design, operational experiences and beam results obtained with the SNS H- ion source and LEBT at Berkeley Lab

The ion source and Low-Energy Transport (LEBT) system that will provide H{sup -} ion beams to the Spallation Neutron Source (SNS)** Front End and the accelerator chain have been developed into a mature unit that fully satisfies the operational requirements through the commissioning and early operating phases of SNS. Compared to the early R&D version, many features of the ion source have been improved, and reliable operation at 6% duty factor has been achieved producing beam currents in the 35-mA range and above. LEBT operation proved that the purely electrostatic focusing principle is well suited to inject the ion beam into the RFQ accelerator, including the steering and pre-chopping functions. This paper will discuss the latest design features of the ion source and LEBT, give performance data for the integrated system, and report on commissioning results obtained with the SNS RFQ and Medium-Energy Beam Transport (MEBT) system. Prospects for further improvements will be outlined in concluding remarks.
Date: April 15, 2002
Creator: Keller, R.; Thomae, R.; Stockli, M. & Welton, R.
Object Type: Article
System: The UNT Digital Library
Disruption of NBS1 gene leads to early embryonic lethality in homozygous null mice and induces specific cancer in heterozygous mice (open access)

Disruption of NBS1 gene leads to early embryonic lethality in homozygous null mice and induces specific cancer in heterozygous mice

Nijmegen breakage syndrome (NBS) is a rare autosomal recessive chromosome instability syndrome characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition, with cellular features similar to that of ataxia telangiectasia (AT). NBS results from mutations in the mammalian gene Nbs1 that codes for a 95-kDa protein called nibrin, NBS1, or p95. To establish an animal model for NBS, we attempted to generate NBS1 knockout mice. However, NBS1 gene knockouts were lethal at an early embryonic stage. NBS1 homozygous(-/-) blastocyst cells cultured in vitro showed retarded growth and subsequently underwent growth arrest within 5 days of culture. Apoptosis, assayed by TUNEL staining, was observed in NBSI homozygous(-/-) blastocyst cells cultured for four days. NBSI heterozygous(+/-) mice were normal, and exhibited no specific phenotype for at least one year. However, fibroblast cells from NBSI heterozygous(+/-) mice displayed an enhanced frequency of spontaneous transformation to anchorage-independent growth as compared to NBS1 wild-type(+/+) cells. Furthermore, heterozygous(+/-) mice exhibited a high incidence of hepatocellular carcinoma after one year compared to wild-type mice, even though no significant differences in the incidence of other tumors such as lung adenocarcinoma and lymphoma were observed. Taken together, these results strongly suggest that NBS1 heterozygosity and reduced NBSI expression induces …
Date: April 15, 2002
Creator: Kurimasa, Akihiro; Burma, Sandeep; Henrie, Melinda; Ouyang, Honghai; Osaki, Mitsuhiko; Ito, Hisao et al.
Object Type: Report
System: The UNT Digital Library
Documentation for FY2002 BTS GPRA Metrics (open access)

Documentation for FY2002 BTS GPRA Metrics

PNNL estimated the FY2002 energy, environmental, and financial benefits (i.e., metrics) of the technologies and practices in the U.S. Department of Energy's (DOE's) Office of Building Technology, State and Community Programs (BTS). BTS uses the estimates of benefits as part of its annual budget request. This report includes an overview of the analytical approaches used to estimate energy savings for the FY2002 appropriated budget for BTS. The report also includes descriptions of key assumptions and the methodology that is used to calculate energy savings estimates for each BTS program.
Date: April 15, 2002
Creator: Hostick, Donna J.; Belzer, David B.; Cort, Katherine A. & Dirks, James A.
Object Type: Report
System: The UNT Digital Library
Documentation for FY2003 BTS GPRA Metrics (open access)

Documentation for FY2003 BTS GPRA Metrics

PNNL estimated the FY2003 energy, environmental, and financial benefits (i.e., metrics) of the technologies and practices in the U.S. Department of Energy's (DOE's) Office of Building Technology, State and Community Programs (BTS). BTS uses the estimates of benefits as part of its annual budget request. This report includes an overview of the analytical approaches used to estimate energy savings for the FY2003 appropriated budget for BTS. The report also includes descriptions of key assumptions and the methodology that is used to calculate energy savings estimates for each BTS program.
Date: April 15, 2002
Creator: Hostick, Donna J.; Belzer, David B.; Cort, Katherine A.; Dirks, James A. & Pool, Rita H.
Object Type: Report
System: The UNT Digital Library
The effect of penetration factor, deposition, and environmental factors on the indoor concentration of PM2.5 sulfate, nitrate, and carbon (open access)

The effect of penetration factor, deposition, and environmental factors on the indoor concentration of PM2.5 sulfate, nitrate, and carbon

Indoor exposure to particles of outdoor origin constitutes an important exposure pathway. We conducted an intensive set of indoor particle measurements in an unoccupied house under differing operating conditions. Real-time measurements were conducted both indoors and outdoors, including PM2.5 nitrate, sulfate, and carbon. Because the time-scale of the fluctuations in outdoor particle concentrations and meteorological conditions are often similar to the time constant for building air exchange, a steady state concentration may never be reached. The time-series experimental data were used to determine the effect of changes in air exchange rate and indoor/outdoor temperature and relative humidity differences on indoor particle concentrations. A multivariate regression was performed to investigate the difference between measured indoor concentrations and results from a simple time-dependent physical model. Environmental conditions had a significant effect on indoor concentrations of all three PM2.5 species, but did not explain all of the model variation.
Date: April 15, 2002
Creator: Thatcher, T. L.; Lunden, M. M.; Sextro, R. G.; Hering, S. & Brown, N. J.
Object Type: Article
System: The UNT Digital Library
Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source (open access)

Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source

Carbon-doped GaN was grown by plasma-assisted molecular-beam epitaxy using carbon tetrachloride vapor as the dopant source. For moderate doping mainly acceptors were formed, yielding semi-insulating GaN. However at higher concentrations p-type conductivity was not observed, and heavily doped films (>5 x 10{sup 20} cm{sup -3}) were actually n-type rather than semi-insulating. Photoluminescence measurements showed two broad luminescence bands centered at 2.2 and 2.9 eV. The intensity of both bands increased with carbon content, but the 2.2 eV band dominated in n-type samples. Intense, narrow ({approx}6 meV) donor-bound exciton peaks were observed in the semi-insulating samples.
Date: April 15, 2002
Creator: Armitage, Rob; Yang, Qing; Feick, Henning; Park, Yeonjoon & Weber, Eicke R.
Object Type: Article
System: The UNT Digital Library
Employing Thin HPGe Detectors for Gamma-Ray Imaging (open access)

Employing Thin HPGe Detectors for Gamma-Ray Imaging

We have evaluated a collimator-less gamma-ray imaging system, which is based on thin layers of double-sided strip HPGe detectors. The position of individual gamma-ray interactions will be deduced by the strip addresses and the Ge layers which fired. Therefore, high bandwidth pulse processing is not required as in thick Ge detectors. While the drawback of such a device is the increased number of electronics channels to be read out and processed, there are several advantages, which are particularly important for remote applications: the operational voltage can be greatly reduced to fully deplete the detector and no high bandwidth signal processing electronics is required to determine positions. Only a charge sensitive preamplifier, a slow pulse shaping amplifier, and a fast discriminator are required on a per channel basis in order to determine photon energy and interaction position in three dimensions. Therefore, the power consumption and circuit board real estate can be minimized. More importantly, since the high bandwidth signal shapes are not used to determine the depth position, lower energy signals can be processed. The processing of these lower energy signals increases the efficiency for the recovery of small angle scattering. Currently, we are studying systems consisting of up to ten …
Date: April 15, 2002
Creator: Vetter, K; Mihailescu, L; Ziock, K; Burks, M; Hull, E; Madden, N et al.
Object Type: Article
System: The UNT Digital Library
ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION (open access)

ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION

This quarterly report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 1/3/2001 through 4/02/2002. Most of the achievements are milestones in our efforts to complete the tasks and subtasks that constitute the project objectives, and we are currently on schedule to complete Phase I activities by 10/2002, the milestone date from the original project timeline. As indicated in the list of accomplishments below, we are continuing to evaluate candidate organisms and growth surfaces, and we are expanding the test facilities in preparation for scaled up system-level testing. Specific results and accomplishments for the first quarter of 2002 include: Organisms and Growth Surfaces: (1) Isolate 1.2 s.c. (2) has been selected for further investigations because of its favorable growth properties. (2) Research on optimal conditions for the growth of cyanobacterial isolates from YNP should be carried out using distilled water which has more stable chemical parameters, although tap water use may be permissible during full scale operations (at the cost of longer organism doubling times). (3) Tr. 9.4 WF is able to generate a biofilm on an Omnisil surface. Over the long term Omnisil does not inhibit the growth of TR 9.4 isolate, …
Date: April 15, 2002
Creator: Kremer, Dr. Gregory; Bayless, David J.; Vis, Dr. Morgan; Prudich, Dr. Michael; Cooksey, Dr. Keith & Muhs, Dr. Jeff
Object Type: Report
System: The UNT Digital Library
Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report (open access)

Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report

Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. More laboratory tests have been performed in this quarter. The analysis performed on the testing data showed: (1) abnormal rotational accelerations can be used as the indicator of the rock interfaces, and (2) the sharp drops of drilling thrust and torque agree well with the locations of fractures.
Date: April 15, 2002
Creator: Peng, Syd S.
Object Type: Report
System: The UNT Digital Library
Investigations of low amplitude radio frequency pulses at and awayfro m rotary resonance conditions for I = 5/2 nuclei (open access)

Investigations of low amplitude radio frequency pulses at and awayfro m rotary resonance conditions for I = 5/2 nuclei

Additional experimental evidence of rotary resonance effects for multiple-quantum coherence conversion in a spin-5/2 system is presented. Two dimensional plots of the relative efficiency of MQ excitation and conversion are given as a function of radio frequency (rf) amplitude and pulse width. Data are presented for the excitation of five-quantum coherence (5QC), as well as for 5QC to three-quantum coherence (3QC) conversion, 5QC to 1QC (the central transition coherence) conversion, and 3QC to 1QC conversion. A two-fold increase in the signal-to-noise ratio is achieved by substituting low amplitude rf pulses in place of hard rf pulses for 5QC excitation and 5QC to 3QC conversion in a mixed multiple-quantum MAS (MMQMAS) experiment. The anisotropic line shape for the low amplitude rf pulse version of the MMQMAS experiment was observed to be distorted from the MAS line shape. The cause and implications of the distortion are discussed.
Date: April 15, 2002
Creator: Logan, John W.; Urban, Jeffry T.; Walls, Jamie D.; Lim, Kwang Hun; Jerschow, Alexej & Pines, Alexander
Object Type: Article
System: The UNT Digital Library
Modeling of Intellite 3 Layer Deformable Mirror (open access)

Modeling of Intellite 3 Layer Deformable Mirror

This is a report on modeling of the Intellite three layer membrane mirror design. The goal of this project was to provide Intellite with a model that will allow them to design a mirror with confidence.
Date: April 15, 2002
Creator: Papavasiliou, A
Object Type: Report
System: The UNT Digital Library