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Theoretical Studies in Heterogenous Catalysis: Towards a Rational Design of Novel Catalysts for Hydrodesulfurization and Hydrogen Production (open access)

Theoretical Studies in Heterogenous Catalysis: Towards a Rational Design of Novel Catalysts for Hydrodesulfurization and Hydrogen Production

Traditionally, knowledge in heterogeneous catalysis has come through empirical research. Nowadays, there is a clear interest to change this since millions of dollars in products are generated every year in the chemical and petrochemical industries through catalytic processes. To obtain a fundamental knowledge of the factors that determine the activity of heterogeneous catalysts is a challenge for modern science since many of these systems are very complex in nature. In principle, when a molecule adsorbs on the surface of a heterogeneous catalyst, it can interact with a large number of bonding sites. It is known that the chemical properties of these bonding sites depend strongly on the chemical environment around them. Thus, there can be big variations in chemical reactivity when going from one region to another in the surface of a heterogeneous catalyst. A main objective is to understand how the structural and electronic properties of a surface affect the energetics for adsorption processes and the paths for dissociation and chemical reactions. In recent years, advances in instrumentation and experimental procedures have allowed a large series of detailed works on the surface chemistry of heterogeneous catalysts. In many cases, these experimental studies have shown interesting and unique phenomena. Theory …
Date: October 1, 2008
Creator: Rodriguez,J.A. & Liu, P.
System: The UNT Digital Library
Couplings between changes in the climate system and biogeochemistry (open access)

Couplings between changes in the climate system and biogeochemistry

The Earth's climate is determined by a number of complex connected physical, chemical and biological processes occurring in the atmosphere, land and ocean. The radiative properties of the atmosphere, a major controlling factor of the Earth's climate, are strongly affected by the biophysical state of the Earth's surface and by the atmospheric abundance of a variety of trace constituents. These constituents include long-lived greenhouse gases (LLGHGs) such as carbon dioxide (CO{sub 2}), methane (CH{sub 4}) and nitrous oxide (N{sub 2}O), as well as other radiatively active constituents such as ozone and different types of aerosol particles. The composition of the atmosphere is determined by processes such as natural and anthropogenic emissions of gases and aerosols, transport at a variety of scales, chemical and microphysical transformations, wet scavenging and surface uptake by the land and terrestrial ecosystems, and by the ocean and its ecosystems. These processes and, more generally the rates of biogeochemical cycling, are affected by climate change, and involve interactions between and within the different components of the Earth system. These interactions are generally nonlinear and may produce negative or positive feedbacks to the climate system. An important aspect of climate research is to identify potential feedbacks and assess …
Date: October 1, 2007
Creator: Menon, Surabi; Denman, Kenneth L.; Brasseur , Guy; Chidthaisong, Amnat; Ciais, Philippe; Cox, Peter M. et al.
System: The UNT Digital Library
Universal Interconnection Technology Workshop Proceedings (open access)

Universal Interconnection Technology Workshop Proceedings

The Universal Interconnection Technology (UIT) Workshop - sponsored by the U.S. Department of Energy, Distributed Energy and Electric Reliability (DEER) Program, and Distribution and Interconnection R&D - was held July 25-26, 2002, in Chicago, Ill., to: (1) Examine the need for a modular universal interconnection technology; (2) Identify UIT functional and technical requirements; (3) Assess the feasibility of and potential roadblocks to UIT; (4) Create an action plan for UIT development. These proceedings begin with an overview of the workshop. The body of the proceedings provides a series of industry representative-prepared papers on UIT functions and features, present interconnection technology, approaches to modularization and expandability, and technical issues in UIT development as well as detailed summaries of group discussions. Presentations, a list of participants, a copy of the agenda, and contact information are provided in the appendices of this document.
Date: October 1, 2002
Creator: Sheaffer, P.; Lemar, P.; Honton, E. J.; Kime, E.; Friedman, N. R.; Kroposki, B. et al.
System: The UNT Digital Library
Program and Abstracts: DOE Solar Program Review Meeting 2004, 25--28 October 2004, Denver, Colorado (open access)

Program and Abstracts: DOE Solar Program Review Meeting 2004, 25--28 October 2004, Denver, Colorado

This booklet contains the agenda and abstracts for the 2004 U.S. DOE Solar Energy Technologies Program Review Meeting. The meeting was held in Denver, Colorado, October 25-28, 2004. More than 240 abstracts are contained in this publication. Topic areas for the research papers include laboratory research, program management, policy analysis, and deployment of solar technologies.
Date: October 1, 2004
Creator: unknown
System: The UNT Digital Library
PROTEIN QUALITY CONTROL IN BACTERIAL CELLS: INTEGRATED NETWORKS OF CHAPERONES AND ATP-DEPENDENT PROTEASES. (open access)

PROTEIN QUALITY CONTROL IN BACTERIAL CELLS: INTEGRATED NETWORKS OF CHAPERONES AND ATP-DEPENDENT PROTEASES.

It is generally accepted that the information necessary to specify the native, functional, three-dimensional structure of a protein is encoded entirely within its amino acid sequence; however, efficient reversible folding and unfolding is observed only with a subset of small single-domain proteins. Refolding experiments often lead to the formation of kinetically-trapped, misfolded species that aggregate, even in dilute solution. In the cellular environment, the barriers to efficient protein folding and maintenance of native structure are even larger due to the nature of this process. First, nascent polypeptides must fold in an extremely crowded environment where the concentration of macromolecules approaches 300-400 mg/mL and on average, each ribosome is within its own diameter of another ribosome (1-3). These conditions of severe molecular crowding, coupled with high concentrations of nascent polypeptide chains, favor nonspecific aggregation over productive folding (3). Second, folding of newly-translated polypeptides occurs in the context of their vehtorial synthesis process. Amino acids are added to a growing nascent chain at the rate of {approx}5 residues per set, which means that for a 300 residue protein its N-terminus will be exposed to the cytosol {approx}1 min before its C-terminus and be free to begin the folding process. However, because protein …
Date: October 1, 2002
Creator: Flanagan, J. M. & Bewley, M. C.
System: The UNT Digital Library
Improving Steam System Performance: A Sourcebook for Industry (open access)

Improving Steam System Performance: A Sourcebook for Industry

A sourcebook designed to provide steam system users with a reference outlining opportunities to improve system performance and optimize energy efficiency in industrial energy systems.
Date: October 1, 2004
Creator: unknown
System: The UNT Digital Library
Steam System Opportunity Assessment for the Pulp and Paper, Chemical Manufacturing, and Petroleum Refining Industries: Main Report (open access)

Steam System Opportunity Assessment for the Pulp and Paper, Chemical Manufacturing, and Petroleum Refining Industries: Main Report

This report assesses steam generation and use in the pulp and paper, chemical, and petroleum refining industries, and estimates the potential for energy savings from implementation of steam system performance and efficiency improvements.
Date: October 1, 2002
Creator: unknown
System: The UNT Digital Library
HIV-AIDS Information Resources from the NLM - ACIO (open access)

HIV-AIDS Information Resources from the NLM - ACIO

As the treatment and management of HIV/AIDS continues to evolve with new scientific breakthroughs, treatment discoveries, and management challenges, it is difficult for people living with HIV/AIDS and those who care for them to keep up with the latest information on HIV/AIDS screening and testing, prevention, treatment, and research. The National Library of Medicine (NLM), of the National Institutes of Health, has a wealth of health information resources freely available on the Internet to address these needs.
Date: October 1, 2010
Creator: Templin-Branner, W.
System: The UNT Digital Library
Superconducting Magnet Technology for Future Hadron Colliders (open access)

Superconducting Magnet Technology for Future Hadron Colliders

The application of superconducting magnets to large-scale particle accelerators was successfully demonstrated with the completion of the Tevatron at Fermilab in 1983. This machine, utilizing dipole magnets operating at 4.5 T, has been operating successfully for the past 12 years. This success was followed a few years later by HERA, an electron-proton collider that uses superconducting quadrupoles and dipoles of a design similar to those in the Tevatron. The next major project was the ill-fated SSC, which was cancelled in 1993. However, the SSC R&D effort did succeed in demonstrating the reliable operation of dipole magnets up to 6.6 T. The LHC, now under construction, pushes the ductile superconductor, NbTi, to its limit in dipoles designed to operate at fields of 8.6 T at 1.8 K. Several recent studies have addressed the issues involved in taking the next step beyond the LHC. The Division of Particles and Fields Workshop on Future Hadron Facilities in the U.S., held at Indiana U. in 1994, examined two possible facilities--a 2-TeV on 2-TeV collider and a 30-Tev on 30-Tev collider. The participants arrived at the following conclusions with regard to superconducting magnets: (1) Superconducting magnets are the enabling technology for high energy colliders. As …
Date: October 1, 1994
Creator: Scanlan, R. M.; Barletta, W. A.; Dell'Orco, D.; McInturff, A. D.; Asner, A.; Collings, E. W. et al.
System: The UNT Digital Library
Spectroscopy of ions using fast beams and ion traps (open access)

Spectroscopy of ions using fast beams and ion traps

A knowledge of the spectra of ionized atoms is of importance in many fields. They can be studied in a wide variety of light sources. In recent years techniques coming under the broad heatings of fast beams and ion traps have been used extensively for such investigations. This article considers the advantages that various techniques have for particular applications.
Date: October 1, 2004
Creator: Pinnington, E. H. & Trabert, E.
System: The UNT Digital Library
[Abilene Board of Commissioners Minutes: 1954-1957] (open access)

[Abilene Board of Commissioners Minutes: 1954-1957]

Ledger containing minutes of the city Board of Commissioners in Abilene, Texas documenting the group's discussions and activities from October 1, 1954 to June 27, 1957. An index with names is included at the front.
Date: 1954-10-01/1957-06-27
Creator: Abilene (Tex.)
System: The Portal to Texas History
[D. M. O'Connor General Business Ledger: 1891-1898] (open access)

[D. M. O'Connor General Business Ledger: 1891-1898]

Ledger kept by Dennis M. O'Connor documenting sales by customer, expenses -- including cattle purchased -- and information related to properties and livestock.
Date: 1891-10-01/1898-01-19
Creator: O'Connor, Dennis Martin
System: The Portal to Texas History
Winnsboro, Texas: Yesterday, Today and Tomorrow (open access)

Winnsboro, Texas: Yesterday, Today and Tomorrow

This book is a reproduction of the original 1952 publication, which is the only bound copy of the history of Winnsboro, Texas. It includes information about the original settlers, the general organization of the city, the railroad system, the original schools, churches and businesses in Winnsboro, as well as information about agriculture and farming.
Date: October 1, 2003
Creator: Suiter, Will D.
System: The Portal to Texas History
Minutes of the Organization and First Annual Session of the Denton County Baptist Association (open access)

Minutes of the Organization and First Annual Session of the Denton County Baptist Association

Minutes of the Organization and First Annual Session of the Denton County Baptist Association. The booklet contains the list of delegates and the location of their churches, constitution, rules of order, and the declaration of faith of the association.
Date: 1886-10-01~
Creator: Denton County Baptist Association
System: The Portal to Texas History
Evaluated Nuclear Data (open access)

Evaluated Nuclear Data

This chapter describes the current status of evaluated nuclear data for nuclear technology applications. We start with evaluation procedures for neutron-induced reactions focusing on incident energies from the thermal energy up to 20 MeV, though higher energies are also mentioned. This is followed by examining the status of evaluated neutron data for actinides that play dominant role in most of the applications, followed by coolants/moderators, structural materials and fission products. We then discuss neutron covariance data that characterize uncertainties and correlations. We explain how modern nuclear evaluated data libraries are validated against an extensive set of integral benchmark experiments. Afterwards, we briefly examine other data of importance for nuclear technology, including fission yields, thermal neutron scattering and decay data. A description of three major evaluated nuclear data libraries is provided, including the latest version of the US library ENDF/B-VII.0, European JEFF-3.1 and Japanese JENDL-3.3. A brief introduction is made to current web retrieval systems that allow easy access to a vast amount of up-to-date evaluated nuclear data for nuclear technology applications.
Date: October 1, 2010
Creator: Oblozinsky, P.; Oblozinsky, P.; Herman, M. & Mughabghab, S. F.
System: The UNT Digital Library
Domestic Water Conservation Technologies: Federal Energy Management Program (FEMP) Federal Technology Alert (Booklet) (open access)

Domestic Water Conservation Technologies: Federal Energy Management Program (FEMP) Federal Technology Alert (Booklet)

Executive Order 13123 calls for the Federal government to conserve water as well as energy in its 500,000 facilities. To help set priorities among water-saving measures, the Federal Energy Management Program conducted a study of Federal water use in 1997. The study indicated that the government consumes more than 50% of its water in just three types of Federal facilities: housing, hospitals, and office buildings. These facilities have enough kitchens, rest rooms, and laundry areas to provide facility managers with many opportunities to begin reducing their water use (and utility costs) with appropriate water-saving fixtures and products. Therefore, this Federal Technology Alert focuses on domestic technologies, products, and appliances such as water-efficient faucets, showerheads, toilets, urinals, washing machines, and dishwashers. Conserving water also saves the energy needed to treat, pump, and heat that water in homes, businesses, and other buildings.
Date: October 1, 2002
Creator: unknown
System: The UNT Digital Library
METAL OXIDE NANOPARTICLES (open access)

METAL OXIDE NANOPARTICLES

This chapter covers the fundamental science, synthesis, characterization, physicochemical properties and applications of oxide nanomaterials. Explains fundamental aspects that determine the growth and behavior of these systems, briefly examines synthetic procedures using bottom-up and top-down fabrication technologies, discusses the sophisticated experimental techniques and state of the art theory results used to characterize the physico-chemical properties of oxide solids and describe the current knowledge concerning key oxide materials with important technological applications.
Date: October 1, 2007
Creator: Fernandez-Garcia, M. & Rodgriguez, J. A.
System: The UNT Digital Library
Full Text of the Game, Fish, and Oyster Laws of Texas, October 1934 (open access)

Full Text of the Game, Fish, and Oyster Laws of Texas, October 1934

Text of laws governing fishing and oyster culture, as well as regulation by the Game, Fish, and Oyster Commission.
Date: October 1, 1934
Creator: Texas. Game, Fish, and Oyster Commission.
System: The Portal to Texas History
Natural Gas Buses: Separating Myth from Fact; Autobuses Urbanos de Gas Natural: Separemos el Mito de la Realidad (open access)

Natural Gas Buses: Separating Myth from Fact; Autobuses Urbanos de Gas Natural: Separemos el Mito de la Realidad

Using a myth vs. fact format, this fact sheet addresses common public misconceptions about compressed natural gas buses.
Date: October 1, 2001
Creator: LaRocque, T.
System: The UNT Digital Library
Small Wind Electric Systems: A Vermont Consumer's Guide (open access)

Small Wind Electric Systems: A Vermont Consumer's Guide

The Vermont Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a state wind resource map and a list of state incentives and state contacts for more information.
Date: October 1, 2001
Creator: O'Dell, K.
System: The UNT Digital Library
FEMP Renewable Energy Fact Sheet: Photovoltaics (open access)

FEMP Renewable Energy Fact Sheet: Photovoltaics

Photovoltaic energy systems, which convert sunlight to electricity, can meet many different needs in Federal facilities. This fact sheet describes how photovoltaic (PV) energy systems can be used to provide electricity for lighting, communications, refrigeration, fans, signs, pumps, drilling equipment, emergency power packs, and cathodic (corrosion) protection, among others. Applications for PV power in Federal facilities include staff housing, parking areas, campgrounds, marinas, visitor centers, roadside communications equipment, ranger stations, underground pipelines, irrigation and disinfecting systems, and disaster response units. PV systems are particularly suitable and cost-effective for facilities that now use diesel power or that are in remote areas far from electric power lines.
Date: October 1, 1999
Creator: unknown
System: The UNT Digital Library
Oral History Interview with Charles C. Christensen, October 1, 1979 (open access)

Oral History Interview with Charles C. Christensen, October 1, 1979

Interview with Navy veteran Charles C. Christensen. The interview includes Christensen's personal experiences while aboard the auxiliary repair ship USS Argonne during the Japanese attack at Pearl Harbor on December 7, 1941. The interview includes an appendix with postcards and letters.
Date: October 1, 1979
Creator: Marcello, Ronald E. & Christensen, Charles C.
System: The UNT Digital Library
Oral History Interview with L. E. Casterline, October 1, 1971 (open access)

Oral History Interview with L. E. Casterline, October 1, 1971

Interview with L. E. Casterline, a fisherman from Fulton, Texas. Casterline discusses his origins in the seafood business, the evolution of large fishing boats and how his company uses them, shrimping practice, differences between towns in the Aransas area, the seafood market, the Parks and Wildlife Department marine lab in Rockport, moving his business, and controversy around mud dredging among clam beds.
Date: October 1, 1971
Creator: Stephens, A. Ray & Casterline, L. E.
System: The UNT Digital Library
Oral History Interview with D. D. Hill, October 1, 1989 (open access)

Oral History Interview with D. D. Hill, October 1, 1989

Interview with D. D. Hill, a United States Navy veteran from Pharr, Texas, regarding his experiences and memories of the Japanese attack on Pearl Harbor of December 7, 1941 while aboard the destroyer USS Dewey.
Date: October 1, 1989
Creator: Marcello, Ronald E. & Hill, D. D.
System: The UNT Digital Library