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13th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Extended Abstracts and Papers (open access)

13th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Extended Abstracts and Papers

The 13th Workshop will provide a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. It will offer an excellent opportunity for researchers in private industry and at universities to prioritize mutual needs for future collaborative research. The workshop is intended to address the fundamental aspects of impurities and defects in silicon: their properties, the dynamics during device processing, and their application for developing low-cost processes for manufacturing high-efficiency silicon solar cells. A combination of oral, poster, and discussion sessions will review recent advances in crystal growth, new cell structures, new processes and process characterization techniques, and cell fabrication approaches suitable for future manufacturing demands.
Date: August 1, 2003
Creator: Sopori, B. L.; Rand, J.; Saitoh, T.; Sinton, R.; Stavola, M.; Swanson, D. et al.
System: The UNT Digital Library
14th Workshop on Crystalline Silicon Solar Cells & Modules: Materials and Processes; Extended Abstracts and Papers (open access)

14th Workshop on Crystalline Silicon Solar Cells & Modules: Materials and Processes; Extended Abstracts and Papers

The 14th Workshop will provide a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. It will offer an excellent opportunity for researchers in private industry and at universities to prioritize mutual needs for future collaborative research. The workshop is intended to address the fundamental properties of PV silicon, new solar cell designs, advanced solar cell processing techniques, and cell-related module issues. A combination of oral presentations by invited speakers, poster sessions, and discussion sessions will review recent advances in crystal growth, new cell designs, new processes and process characterization techniques, cell fabrication approaches suitable for future manufacturing demands, and solar cell encapsulation. This year's theme, ''Crystalline Si Solar Cells: Leapfrogging the Barriers,'' reflects the continued success of crystalline Si PV in overcoming technological barriers to improve solar cell performance and lower the cost of Si PV. The workshop will consist of presentations by invited speakers, followed by discussion sessions. In addition, there will be two poster sessions presenting the latest research and development results. Some presentations will address recent technologies in the microelectronics field that may have a direct bearing on PV. The sessions will include: Advances in …
Date: August 1, 2004
Creator: Sopori, B. L.
System: The UNT Digital Library
2001-2002 Federal Energy Saver Showcases (open access)

2001-2002 Federal Energy Saver Showcases

This book recognizes Federal Energy Saver Showcase winners from both 2001 and 2002. These Federal facilities have been awarded for implementing a variety of significant energy and water efficiency improvement projects. These projects, which employ a wide variety of technologies and products, represent savings in both dollars and environmental impact.
Date: July 1, 2003
Creator: unknown
System: The UNT Digital Library
Aberration-Coreected Electron Microscopy at Brookhaven National Laboratory (open access)

Aberration-Coreected Electron Microscopy at Brookhaven National Laboratory

The last decade witnessed the rapid development and implementation of aberration correction in electron optics, realizing a more-than-70-year-old dream of aberration-free electron microscopy with a spatial resolution below one angstrom [1-9]. With sophisticated aberration correctors, modern electron microscopes now can reveal local structural information unavailable with neutrons and x-rays, such as the local arrangement of atoms, order/disorder, electronic inhomogeneity, bonding states, spin configuration, quantum confinement, and symmetry breaking [10-17]. Aberration correction through multipole-based correctors, as well as the associated improved stability in accelerating voltage, lens supplies, and goniometers in electron microscopes now enables medium-voltage (200-300kV) microscopes to achieve image resolution at or below 0.1nm. Aberration correction not only improves the instrument's spatial resolution but, equally importantly, allows larger objective lens pole-piece gaps to be employed thus realizing the potential of the instrument as a nanoscale property-measurement tool. That is, while retaining high spatial resolution, we can use various sample stages to observe the materials response under various temperature, electric- and magnetic- fields, and atmospheric environments. Such capabilities afford tremendous opportunities to tackle challenging science and technology issues in physics, chemistry, materials science, and biology. The research goal of the electron microscopy group at the Dept. of Condensed Matter Physics and …
Date: April 1, 2008
Creator: Zhu, Y. & Wall, J.
System: The UNT Digital Library
ACCELERATED PROCESSING OF SB4 AND PREPARATION FOR SB5 PROCESSING AT DWPF (open access)

ACCELERATED PROCESSING OF SB4 AND PREPARATION FOR SB5 PROCESSING AT DWPF

The Defense Waste Processing Facility (DWPF) initiated processing of Sludge Batch 4 (SB4) in May 2007. SB4 was the first DWPF sludge batch to contain significant quantities of HM or high Al sludge. Initial testing with SB4 simulants showed potential negative impacts to DWPF processing; therefore, Savannah River National Laboratory (SRNL) performed extensive testing in an attempt to optimize processing. SRNL's testing has resulted in the highest DWPF production rates since start-up. During SB4 processing, DWPF also began incorporating waste streams from the interim salt processing facilities to initiate coupled operations. While DWPF has been processing SB4, the Liquid Waste Organization (LWO) and the SRNL have been preparing Sludge Batch 5 (SB5). SB5 has undergone low-temperature aluminum dissolution to reduce the mass of sludge for vitrification and will contain a small fraction of Purex sludge. A high-level review of SB4 processing and the SB5 preparation studies will be provided.
Date: December 1, 2008
Creator: Herman, C
System: The UNT Digital Library
Advanced process analysis for petroleum refining (open access)

Advanced process analysis for petroleum refining

This is a fact sheet on an advanced computer analysis system for petroleum refining written for the NICE3 Program.
Date: February 1, 2000
Creator: National Renewable Energy Laboratory (U.S.)
System: The UNT Digital Library
Advancements in the characterization of 'hyper-thin' oxynitride gate dielectrics through exit wave reconstruction HRTEM and XPS (open access)

Advancements in the characterization of 'hyper-thin' oxynitride gate dielectrics through exit wave reconstruction HRTEM and XPS

The physical thickness of silicon oxynitride gate dielectric materials currently in development have dimensions in the range of 15-20 Angstrom ({approx}6-8 oxygen atoms), while approaching the dielectric constant equivalent oxide thickness (EOT) of 12 Angstrom silicon dioxide. These structures present serious challenges in meeting stringent requirements within the semiconductor industry for precise determination of thickness, interfacial roughness and chemical distribution. Limitations in conventional HRTEM must be removed that would minimize errors in such measurements. Our approach was to use the National Center for Electron Microscopy (NCEM) One Angstrom Microscope (O Angstrom M), together with focal series acquisition (FSA) and exit wave reconstruction (EWR) techniques to obtain <0.8A interpretable resolution. HRTEM data on the same oxynitride materials from an aberration corrected (Cs=0) microscope were also collected as part of this work, as were scanning TEM (STEM) measurements. The H RTEM characterization provides an absolute calibration and validation for a precise ''near-line'' metrology to determine gate oxide thickness and nitrogen dose using x-ray photoelectron spectroscopy (XPS).
Date: September 1, 2002
Creator: Principe, E.L.; Watson, D.G. & Kisielowski, C.
System: The UNT Digital Library
Aerosol, Clouds, and Climate Change (open access)

Aerosol, Clouds, and Climate Change

Earth's climate is thought to be quite sensitive to changes in radiative fluxes that are quite small in absolute magnitude, a few watts per square meter, and in relation to these fluxes in the natural climate. Atmospheric aerosol particles exert influence on climate directly, by scattering and absorbing radiation, and indirectly by modifying the microphysical properties of clouds and in turn their radiative effects and hydrology. The forcing of climate change by these indirect effects is thought to be quite substantial relative to forcing by incremental concentrations of greenhouse gases, but highly uncertain. Quantification of aerosol indirect forcing by satellite- or ground-based remote sensing has proved quite difficult in view of inherent large variation in the pertinent observables such as cloud optical depth, which is controlled mainly by liquid water path and only secondarily by aerosols. Limited work has shown instances of large magnitude of aerosol indirect forcing, with local instantaneous forcing upwards of 50 W m{sup 66}-2. Ultimately it will be necessary to represent aerosol indirect effects in climate models to accurately identify the anthropogenic forcing at present and over secular time and to assess the influence of this forcing in the context of other forcings of climate change. …
Date: September 1, 2005
Creator: Schwartz, S. E.
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. 5, No. 2 (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. 5, No. 2

A quarterly magazine with articles the proposed National Energy Policy; the 2001 National Clean Cities Conference including Clean Cities Coalition Award and National Partner Award recipients; station cars (shared my multiple drivers); and new emissions-reducing incentives in Texas.
Date: August 1, 2001
Creator: LaRocque, T.
System: The UNT Digital Library
Analysis and Classification of Mammography Reports Using Maximum Variation Sampling (open access)

Analysis and Classification of Mammography Reports Using Maximum Variation Sampling

Currently, no automated means of detecting abnormal mammograms exist. While knowledge discovery capabilities through data mining and data analytics tools are widespread in many industries, the healthcare industry as a whole lags far behind. Providers are only just beginning to recognize the value of data mining as a tool to analyze patient care and clinical outcomes. The research conducted by the authors investigates the use of genetic algorithms for classification of unstructured mammography reports, which can be later correlated to the images for extraction and testing. In mammography, much effort has been expended to characterize findings in the radiology reports. Various computer-assisted technologies have been developed to assist radiologists in detecting cancer; however, the algorithms still lack high degrees of sensitivity and specificity, and must undergo machine learning against a training set with known pathologies in order to further refine the algorithms with higher validity of truth. In a large database of reports and corresponding images, automated tools are needed just to determine which data to include in the training set. Validation of these data is another issue. Radiologists disagree with each other over the characteristics and features of what constitutes a normal mammogram and the terminology to use in …
Date: January 1, 2011
Creator: Patton, Robert M.; Beckerman, Barbara G. & Potok, Thomas E.
System: The UNT Digital Library
Analysis of Essential Nuclear Reactor Materials (open access)

Analysis of Essential Nuclear Reactor Materials

This book is intended as a laboratory reference tool. The separate book chapters have been written by workers in the various fields covered, with a couple written by the contributing editor, Clement J. Rodden. The chapters were abstracted separately for the database.
Date: January 1, 1964
Creator: Rodden, C. J.
System: The UNT Digital Library
Analysis of Inter-Vehicle Communication Using Network Simulator (open access)

Analysis of Inter-Vehicle Communication Using Network Simulator

Inter-Vehicle Communication (IVC) could be an important component of next-generation Intelligent Transportation System (ITS). It provides wireless connectivity among traveling vehicles to exchange real-time road condition and traffic information to support safe driving and traffic management. IVC system can be considered as a special form of mobile ad-hoc network (MANET). The MANET and IVC are both hot issues for researches. However, there are few domestic literatures combining the two topics. Most of them are discussed separately. Thus, the studies on architecture and protocols of mobile ad-hoc network have great value for establishing vehicular networks. The simulating method is an available way to assess the performance of networks. This paper has a specific description about the network simulator NS-2 . Under the basic of simulating practices, the design method and procedure for MANET simulation are summarized in detail. In this report, two simple IVC scenarios are implemented on NS-2. The quantitative metrics like network throughput, delay and packet-loss are used to assess the performance of MANET for IVC under different vehicular speeds, transport layer protocols and routing protocols. The results indicate that MANET can be used for IVC well. The different speeds and protocols should be chosen based on specific IVC …
Date: January 1, 2013
Creator: Lu, Wei
System: The UNT Digital Library
Anisotropic Hexagonal Boron Nitride Nanomaterials - Synthesis and Applications (open access)

Anisotropic Hexagonal Boron Nitride Nanomaterials - Synthesis and Applications

Boron nitride (BN) is a synthetic binary compound located between III and V group elements in the Periodic Table. However, its properties, in terms of polymorphism and mechanical characteristics, are rather close to those of carbon compared with other III-V compounds, such as gallium nitride. BN crystallizes into a layered or a tetrahedrally linked structure, like those of graphite and diamond, respectively, depending on the conditions of its preparation, especially the pressure applied. Such correspondence between BN and carbon readily can be understood from their isoelectronic structures [1, 2]. On the other hand, in contrast to graphite, layered BN is transparent and is an insulator. This material has attracted great interest because, similar to carbon, it exists in various polymorphic forms exhibiting very different properties; however, these forms do not correspond strictly to those of carbon. Crystallographically, BN is classified into four polymorphic forms: Hexagonal BN (h-BN) (Figure 1(b)); rhombohedral BN (r-BN); cubic BN (c-BN); and wurtzite BN (w-BN). BN does not occur in nature. In 1842, Balmain [3] obtained BN as a reaction product between molten boric oxide and potassium cyanide under atmospheric pressure. Thereafter, many methods for its synthesis were reported. h-BN and r-BN are formed under ambient …
Date: August 1, 2008
Creator: Han,W.Q.
System: The UNT Digital Library
Annual Report Fiscal Year 2001: Office of Industrial Technologies (OIT) Chemical Industry of the Future (open access)

Annual Report Fiscal Year 2001: Office of Industrial Technologies (OIT) Chemical Industry of the Future

The Chemical Annual Report provides program highlights during the past year. Included are updates on technology R&D projects, recent success, and industry trends.
Date: November 1, 2001
Creator: unknown
System: The UNT Digital Library
Application of Synchrotron Radiation in the Geological and Environmental Sciences (open access)

Application of Synchrotron Radiation in the Geological and Environmental Sciences

A survey of some of the different ways that synchrotrons x-ray beams can be used to study geological materials is presented here. This field developed over a period of about 30 years, and it is clear that the geological community has made major use of the many synchrotrons facilities operating around the world during this time period. This was a time of rapid change in the operational performance of the synchrotrons facilities and this in itself has made it possible for geologists to develop new and more refined types of experiments that have yielded many important results. The advance in experimental techniques has proceeded in parallel with a revolution in computing techniques that has made it possible to cope with the great amount of data accumulated in the experiments. It is reasonable, although risky, to speculate about what might be expected to develop in the field during the next five- to ten-year period. It does seem plausible that the rate of change in the performance of what might now be called conventional x-ray storage rings will slow. There are no new facilities that are superior to the ESRF, ALS, APS, or SPring8 facilities under construction or about to come into …
Date: September 1, 1999
Creator: Jones, Keith W.
System: The UNT Digital Library
Assessing the Potential for Renewable Energy on National Forest System Lands (open access)

Assessing the Potential for Renewable Energy on National Forest System Lands

This technical report and CD for the U.S. Department of Agriculture, Forest Service (USFS), evaluates the potential for renewable energy resource development on National Forest System (NFS) lands. USFS can use the report findings to consider potential for development of solar and wind energy resources on NFS lands, in land management decisions. The Geographical Information System (GIS) based analysis resulted in the following findings: (1) Ninety-nine National Forest Units have high potential for power production from one or more of these solar and wind energy sources; and (2) Twenty National Forest Units in nine states have high potential for power production from two or more of these solar and wind energy sources.
Date: January 1, 2005
Creator: unknown
System: The UNT Digital Library
Atomic-Resolution STEM at Low Primary Energies (open access)

Atomic-Resolution STEM at Low Primary Energies

Aberration-corrected scanning transmission electron microscopes (STEMs) can now produce electron probes as small as 1 {angstrom} at 60 keV. This level of performance allows individual light atoms to be imaged in various novel materials including graphene, monolayer boron nitride, and carbon nanotubes. Operation at 60 keV avoids direct knock-on damage in such materials, but some radiation damage often remains, and limits the maximum usable electron dose. Elemental identification by electron energy loss spectroscopy (EELS) is then usefully supplemented by annular dark-field (ADF) imaging, for which the signal is much larger and the spatial resolution significantly better. Because of its strong dependence on the atomic number Z, ADF can be used to identify the chemical type of individual atoms, both heavy and light. We review the instrumental requirements for atomic resolution imaging at 60 keV and lower energies, and we illustrate the kinds of studies that have now become possible by ADF images of graphene, monolayer BN, and single-wall carbon nanotubes, and by ADF images and EEL spectra of carbon nanotubes containing nanopods filled with single atoms of Er. We then discuss likely future developments.
Date: January 1, 2011
Creator: Krivanek, Ondrej L.; Chisholm, Matthew F; Dellby, N. & Murfitt, M. F.
System: The UNT Digital Library
Audio-Magnetotelluric Data Log and Station Location Map for Gerlach Northwest Known Geothermal Resource Area, Nevada (open access)

Audio-Magnetotelluric Data Log and Station Location Map for Gerlach Northwest Known Geothermal Resource Area, Nevada

Observed apparent resistivity data in ohm-meters, standard error data in ohm-meters, and number of observations are tabulated. (JGB)
Date: January 1, 1977
Creator: Long, C. L. & Senterfit, M.
System: The UNT Digital Library
Bacteria in Permafrost (open access)

Bacteria in Permafrost

Significant numbers of viable ancient microorganisms are known to be present within the permafrost. They have been isolated in both polar regions from the cores up to 400 m deep and ground temperatures of -27 C. The age of the cells corresponds to the longevity of the permanently frozen state of the soils, with the oldest cells dating back to {approx}3 million years in the Arctic, and {approx}5 million years in the Antarctic. They are the only life forms known to have retained viability over geological time. Thawing of the permafrost renews their physiological activity and exposes ancient life to modern ecosystems. Thus, the permafrost represents a stable and unique physicochemical complex, which maintains life incomparably longer than any other known habitats. If we take into account the depth of the permafrost layers, it is easy to conclude that they contain a total microbial biomass many times higher than that of the soil cover. This great mass of viable matter is peculiar to permafrost only.
Date: January 1, 2008
Creator: Gilichinsky, David A.; Vishnivetskaya, Tatiana A.; Petrova, Maya A.; Spirina, Elena V.; Mamikin, Vladimir & Rivkina, Elizaveta
System: The UNT Digital Library
Become One In A Million: Partnership Updates -- Million Solar Roofs and Interstate Renewable Energy Council (open access)

Become One In A Million: Partnership Updates -- Million Solar Roofs and Interstate Renewable Energy Council

The Million Solar Roofs Partnership Update is an annual report from all the Partnership and Partners who participate in the Million Solar Roofs Initiative.
Date: June 1, 2004
Creator: unknown
System: The UNT Digital Library
Benefits of stimulating geothermal energy development with tax and research subsidies (open access)

Benefits of stimulating geothermal energy development with tax and research subsidies

A technique is demonstrated for evaluating benefits of subsidies and examples are given for using it to determine the cost-benefit ratio. Examples use two preferential tax treatments as opposed to direct research grants for the high-temperature, low-salinity hydrothermal resources. Results are compared and some conclusions are given. (PCS)
Date: January 1, 1976
Creator: Knutsen, C. A.
System: The UNT Digital Library
Biofuels News, Vol. 2, Issue 3, Summer 99 (open access)

Biofuels News, Vol. 2, Issue 3, Summer 99

The focus of this Biofuels News is biodiesel. Biodiesel is a domestically produced renewable fuel that is made by reacting alcohol (usually methanol or ethanol) with vegetable oils, animal fats, or recycled cooking greases. It can be used neat (pure) or in blends (the most popular is 20% biodiesel blend) with any type of diesel fuel.
Date: September 1, 1999
Creator: Woodward, S.
System: The UNT Digital Library
Biomass Cofiring in Coal-Fired Boilers (open access)

Biomass Cofiring in Coal-Fired Boilers

Cofiring biomass-for example, forestry residues such as wood chips-with coal in existing boilers is one of the easiest biomass technologies to implement in a federal facility. The current practice is to substitute biomass for up to 20% of the coal in the boiler. Cofiring has many benefits: it helps to reduce fuel costs as well as the use of landfills, and it curbs emissions of sulfur oxide, nitrogen oxide, and the greenhouse gases associated with burning fossil fuels. This Federal Technology Alert was prepared by the Department of Energy's Federal Energy Management Program to give federal facility managers the information they need to decide whether they should pursue biomass cofiring at their facilities.
Date: June 1, 2004
Creator: unknown
System: The UNT Digital Library
Buildings Sector Analysis (open access)

Buildings Sector Analysis

A joint NREL, ORNL, and PNNL team conducted market analysis to help inform DOE/EERE's Weatherization and Intergovernmental Program planning and management decisions. This chapter presents the results of the market analysis for the Buildings sector.
Date: August 1, 2005
Creator: Hostick, Donna J.; Nicholls, Andrew K.; McDonald, Sean C. & Hollomon, Jonathan B.
System: The UNT Digital Library