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Fishing for biodiversity: Novel methanopterin-linked C1 transfergenes deduced from the Sargasso Sea metagenome (open access)

Fishing for biodiversity: Novel methanopterin-linked C1 transfergenes deduced from the Sargasso Sea metagenome

The recently generated database of microbial genes from anoligotrophic environment populated by a calculated 1,800 of major phylotypes (the Sargasso Sea metagenome) presents a great source for expanding local databases of genes indicative of a specific function. In this paper we analyze the Sargasso Sea metagenome in terms of the presence of methanopterin-linked C1 transfer genes that are signature for methylotrophy. We conclude that more than 10 phylotypes possessing genes of interest are present in this environment, and a few of these are relatively abundant species. The sequences representative of the major phylotypes do not appear to belong to any known microbial group capable of methanopterin-linked C1 transfer. Instead, they separate from all known sequences on phylogenetic trees, pointing towards their affiliation with a novel microbial phylum. These data imply a broader distribution of methanopterin-linked functions in the microbial world than previously known.
Date: July 1, 2004
Creator: Kalyuzhnaya, Marina G.; Nercessian, Olivier; Lapidus, Alla & Chistoserdova, Ludmila
Object Type: Article
System: The UNT Digital Library
Upgrading Methane Using Ultra-Fast Thermal Swing Adsorption (open access)

Upgrading Methane Using Ultra-Fast Thermal Swing Adsorption

The purpose of this project is to design and demonstrate an approach to upgrade low-BTU methane streams from coal mines to pipeline-quality natural gas. The objective of Phase I of the project was to assess the technical feasibility and cost of upgrading low-BTU methane streams using ultra-fast thermal swing adsorption (TSA) using Velocys modular microchannel process technology. The objective of Phase II is to demonstrate the process at the bench scale. The project is on schedule and on budget. A technical and economic feasibility assessment was completed in Task 3. The proposed Velocys technology appears feasible for the methane upgrading market. Evaluated categories include adsorbent selection, rapid-cycle valve selection, microchannel manufacturability assessment, and system design and cost. The selected adsorbent, granular microporous carbon from either Barnaby-Sutcliffe or Calgon, experimentally demonstrated sufficient methane capacity under differential temperature at 100 pounds per square inch gauge. Several valve options were identified, including candidates that can operate millions of cycles between refurbishment. The microchannel adsorber and desorber designs were made using internal Velocys manufacturability standards, and the associated costs are acceptable as included with the complete nitrogen rejection unit (NRU) cost projection. A system design and cost estimate was completed for the NRU section …
Date: July 1, 2004
Creator: Tonkovich, Anna Lee
Object Type: Report
System: The UNT Digital Library
Search for Excited or Exotic Electron Production Using the Dielectron + Photon Signature at CDF in Run II (open access)

Search for Excited or Exotic Electron Production Using the Dielectron + Photon Signature at CDF in Run II

The author presents a search for excited or exotic electrons decaying to an electron and a photon with high transverse momentum. An oppositely charged electron is produced in association with the excited electron, yielding a final state dielectron + photon signature. The discovery of excited electrons would be a first indication of lepton compositeness. They use {approx} 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the Collider Detector at Fermilab during March 2001 through September 2003. The data are consistent with standard model expectations. Upper limits are set on the experimental cross-section {sigma}({bar p}p {yields} ee* {yields} ee{gamma}) at the 95% confidence level in a contact-interaction model and a gauge-mediated interaction model. Limits are also presented as exclusion regions in the parameter space of the excited electron mass (M{sub e*}) and the compositeness energy scale ({Lambda}). In the contact-interaction model, for which there are no previously published limits, they find M{sub e*} < 906 GeV is excluded for M{sub e*} = {Lambda}. In the gauge-mediated model, the exclusion region in the M{sub e*} versus the phenomenological coupling f/{Lambda} parameter space is extended to M{sub e*} < 430 GeV for f/{Lambda} {approx} 10{sup …
Date: July 1, 2004
Creator: Gerberich, Heather Kay & U., /Duke
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0211 (open access)

Texas Attorney General Opinion: GA-0211

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Whether a county judge whom the State Commission on Judicial Conduct has suspended from office with pay is entitled to his full salary (RQ-0160-GA)
Date: July 1, 2004
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Gridley Ethanol Demonstration Project Utilizing Gasification Technology: Feedstock Supply Plan; March 15, 2004 (open access)

Gridley Ethanol Demonstration Project Utilizing Gasification Technology: Feedstock Supply Plan; March 15, 2004

The report describes a Feedstock Supply Plan for the proposed Gridley Ethanol Demonstration Project to be located in the City of Gridley Industrial Park in Gridley, California. This report also includes information on the establishment of the required infrastructure required for collecting approximately 113,000 Bone Dry Tons (BDT) annually for the proposed facility. Using the Pearson Technology from Aberdeen, Mississippi, and the related engineering assumptions for required feedstock, it is estimated that the proposed Gridley Ethanol Project will use approximately 113,000 BDT of rice straw to produce approximately up to 20 million gallons of ethanol annually, and/or process steam and or electricity. Based on TSS's survey of planted rice acreage in the Sacramento Valley, a total of 379,765 acres of rice are grown within a 30-mile radius of the Gridley site and that 759,530 BDT of recoverable rice straw are generated annually. This volume of rice straw is 6.7 times the 113,000 BDT of tot al feedstock needed by the proposed Gridley facility. Sufficient infrastructure exists with additional market potential for further private market infrastructure expansion in California and the Northwest (Oregon, Washington and Idaho) to collect the annual feedstock requirement of 113,000 BDT for the proposed Gridley Ethanol Demonstration …
Date: July 1, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Wind Farm Power System Model Development: Preprint (open access)

Wind Farm Power System Model Development: Preprint

In some areas, wind power has reached a level where it begins to impact grid operation and the stability of local utilities. In this paper, the model development for a large wind farm will be presented. Wind farm dynamic behavior and contribution to stability during transmission system faults will be examined.
Date: July 1, 2004
Creator: Muljadi, E. & Butterfield, C. P.
Object Type: Article
System: The UNT Digital Library
Multi-Pulse DARHT Machine-Plasma Plume Problem (open access)

Multi-Pulse DARHT Machine-Plasma Plume Problem

The plasma current decay time constant is predicted to be short compared to the pulse length and so self-focusing is predicted for most of the beam pulse. Four- pulse beam envelopes for a high dose case require mitigation, those for a low dose case do not. Methods of mitigation are summarized. Hose instability growth in the plume length is predicted to be minimal.
Date: July 1, 2004
Creator: Lauer, E J
Object Type: Report
System: The UNT Digital Library
NAWIG News: The Quarterly Newsletter of the Native American Wind Interest Group; Summer 2004 (open access)

NAWIG News: The Quarterly Newsletter of the Native American Wind Interest Group; Summer 2004

The United States is home to more than 700 American Indian tribes and Native Alaska villages and corporations located on 96 million acres. Many of these tribes and villages have excellent wind resources that could be commercially developed to meet their electricity needs or for electricity export. The Wind Powering America program engages Native Americans in wind energy development, and as part of that effort, the NAWIG newsletter informs readers of events in the Native American/wind energy community.
Date: July 1, 2004
Creator: unknown
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Photovoltaic and Solar Thermal Modeling with the EnergyPlus Calculation Engine: Preprint (open access)

Photovoltaic and Solar Thermal Modeling with the EnergyPlus Calculation Engine: Preprint

EnergyPlus is a whole-building energy analysis software program developed by DOE. It was recently expanded with the addition of new active solar components for simulation of photovoltaic and solar thermal hot-water heating systems. The active solar models were integrated into the program because low- or zero-energy buildings often use renewable energy resources to accomplish their energy-saving goals. This paper provides an overview of the new models for PV and solar collectors in EnergyPlus and describes some preliminary efforts to validate the implementations.
Date: July 1, 2004
Creator: Griffith, B. T. & Ellis, P. G.
Object Type: Article
System: The UNT Digital Library
State Renewable Energy News -- Vol.13, No. 2, Summer 2004 (Newsletter) (open access)

State Renewable Energy News -- Vol.13, No. 2, Summer 2004 (Newsletter)

This issue, a compilation of renewable electric activities in the states, is prepared for the National Association of Regulatory Utility Commissioners (NARUC). It includes news from Connecticut, Hawaii, Idaho, Illinois, Maryland, Michigan, New York, Rhode Island, Vermont.
Date: July 1, 2004
Creator: unknown
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Optimization of Utility-Scale Wind-Hydrogen-Battery Systems: Preprint (open access)

Optimization of Utility-Scale Wind-Hydrogen-Battery Systems: Preprint

Traditional utility-scale wind energy systems are not dispatchable; that is, the utility cannot instantaneously control their power output. Energy storage, which can come in many forms, is needed to add dispatchability to a wind farm. This study investigates two options: batteries and hydrogen.
Date: July 1, 2004
Creator: Fingersh, L. J.
Object Type: Article
System: The UNT Digital Library
Measurement of the t anti-t production cross-section at s**(1/2) = 1.96-TeV using lifetime tagging (open access)

Measurement of the t anti-t production cross-section at s**(1/2) = 1.96-TeV using lifetime tagging

A measurement of the t{bar t} production cross section in the lepton+jets channels with the D0 detector at {radical}s = 1.96 TeV using the lifetime-tagging techniques is presented. The t{bar t} cross section is estimated from the combination of the e+jets and {mu}+jets channels. The obtained result {sigma}{sub t{bar t}} = 7.47{sub -1.14}{sup +1.22}(stat){sub -1.03}{sup +1.65}(syst) {+-} 0.49(lumi) pb is consistent with the Standard Model expectation.
Date: July 1, 2004
Creator: Khanov, Alexander
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Trombe Walls in Low-Energy Buildings: Practical Experiences; Preprint (open access)

Trombe Walls in Low-Energy Buildings: Practical Experiences; Preprint

Low-energy buildings today improve on passive solar design by incorporating a thermal storage and delivery system called a Trombe wall. Trombe walls were integrated into the envelope of a recently completed Visitor Center at Zion National Park and a site entrance building at the National Wind Technology Center located at the National Renewable Energy Laboratory. NREL helped to design these commercial buildings to minimize energy consumption, using Trombe walls as an integral part of their design.
Date: July 1, 2004
Creator: Torcellini, P. & Pless, S.
Object Type: Article
System: The UNT Digital Library
San Juanico Hybrid System Technical and Institutional Assessment: Preprint (open access)

San Juanico Hybrid System Technical and Institutional Assessment: Preprint

San Juanico is a fishing village of approximately 120 homes in the Municipality of Comondu, Baja California. In April, 1999, a hybrid power system was installed in San Juanico to provide 24-hour power, which was not previously available. Before the installation of the hybrid power system, a field study was conducted to characterize the electrical usage and institutional and social framework of San Juanico. One year after the installation of the hybrid power system a''post-electrification'' study was performed to document the changes that had occurred after the installation. In December of 2003, NREL visited the site to conduct a technical assessment of the system.
Date: July 1, 2004
Creator: Corbus, D.; Newcomb, C. & Yewdall, Z.
Object Type: Article
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 129, No. 5, Ed. 1 Thursday, July 1, 2004 (open access)

The Albany News (Albany, Tex.), Vol. 129, No. 5, Ed. 1 Thursday, July 1, 2004

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: July 1, 2004
Creator: Lucas, Melinda L.
Object Type: Newspaper
System: The Portal to Texas History
NREL Pyrheliometer Comparisons (NPC-2003), September 22 - October 3, 2003, Golden, Colorado (open access)

NREL Pyrheliometer Comparisons (NPC-2003), September 22 - October 3, 2003, Golden, Colorado

NREL Pyrheliometer Comparisons (NPCs) are held annually at the Solar Radiation Research Laboratory (SRRL) in Golden, Colorado. Open to all pyrheliometer owner/operators, the NPC provides an opportunity to determine the unique WRR transfer factor for each participating pyrheliometer.
Date: July 1, 2004
Creator: Stoffel, T.; Reda, I. & Wilcox, S.
Object Type: Report
System: The UNT Digital Library
ACME algorithms for contact in a multiphysics environment API version 2.2. (open access)

ACME algorithms for contact in a multiphysics environment API version 2.2.

An effort is underway at Sandia National Laboratories to develop a library of algorithms to search for potential interactions between surfaces represented by analytic and discretized topological entities. This effort is also developing algorithms to determine forces due to these interactions for transient dynamics applications. This document describes the Application Programming Interface (API) for the ACME (Algorithms for Contact in a Multiphysics Environment) library.
Date: July 1, 2004
Creator: Heinstein, Martin Wilhelm; Glass, Micheal W.; Gullerud, Arne S.; Brown, Kevin H.; Voth, Thomas Eugene & Jones, Reese E.
Object Type: Report
System: The UNT Digital Library
A preliminary report on the development of MATLAB tensor classes for fast algorithm prototyping. (open access)

A preliminary report on the development of MATLAB tensor classes for fast algorithm prototyping.

We describe three MATLAB classes for manipulating tensors in order to allow fast algorithm prototyping. A tensor is a multidimensional or N-way array. We present a tensor class for manipulating tensors which allows for tensor multiplication and 'matricization.' We have further added two classes for representing tensors in decomposed format: cp{_}tensor and tucker{_}tensor. We demonstrate the use of these classes by implementing several algorithms that have appeared in the literature.
Date: July 1, 2004
Creator: Bader, Brett William & Kolda, Tamara Gibson (Sandia National Laboratories, Livermore, CA)
Object Type: Report
System: The UNT Digital Library
Preliminary versions of the MATLAB tensor classes for fast algorithm prototyping. (open access)

Preliminary versions of the MATLAB tensor classes for fast algorithm prototyping.

We present the source code for three MATLAB classes for manipulating tensors in order to allow fast algorithm prototyping. A tensor is a multidimensional or Nway array. This is a supplementary report; details on using this code are provided separately in SAND-XXXX.
Date: July 1, 2004
Creator: Bader, Brett William & Kolda, Tamara Gibson (Sandia National Laboratories, Livermore, CA)
Object Type: Report
System: The UNT Digital Library
An analytically solvable eigenvalue problem for the linear elasticity equations. (open access)

An analytically solvable eigenvalue problem for the linear elasticity equations.

Analytic solutions are useful for code verification. Structural vibration codes approximate solutions to the eigenvalue problem for the linear elasticity equations (Navier's equations). Unfortunately the verification method of 'manufactured solutions' does not apply to vibration problems. Verification books (for example [2]) tabulate a few of the lowest modes, but are not useful for computations of large numbers of modes. A closed form solution is presented here for all the eigenvalues and eigenfunctions for a cuboid solid with isotropic material properties. The boundary conditions correspond physically to a greased wall.
Date: July 1, 2004
Creator: Day, David Minot & Romero, Louis Anthony
Object Type: Report
System: The UNT Digital Library
Sundance 2.0 tutorial. (open access)

Sundance 2.0 tutorial.

Sundance is a system of software components that allows construction of an entire parallel simulator and its derivatives using a high-level symbolic language. With this high-level problem description, it is possible to specify a weak formulation of a PDE and its discretization method in a small amount of user-level code; furthermore, because derivatives are easily available, a simulation in Sundance is immediately suitable for accelerated PDE-constrained optimization algorithms. This paper is a tutorial for setting up and solving linear and nonlinear PDEs in Sundance. With several simple examples, we show how to set up mesh objects, geometric regions for BC application, the weak form of the PDE, and boundary conditions. Each example then illustrates use of an appropriate solver and solution visualization.
Date: July 1, 2004
Creator: Long, Kevin R.
Object Type: Report
System: The UNT Digital Library
AGS Sextupole Error Part II (open access)

AGS Sextupole Error Part II

N/A
Date: July 1, 2004
Creator: L., Hutchinson & Glenn, W.
Object Type: Report
System: The UNT Digital Library
Skew Quadrupole Modulation to Measure Global Betatron Coupling (open access)

Skew Quadrupole Modulation to Measure Global Betatron Coupling

N/A
Date: July 1, 2004
Creator: Y., Luo; Cameron, P.; Lee, R.; Marusic, A.; Pilat, F.; Trbojevic, D. et al.
Object Type: Report
System: The UNT Digital Library
Modeling an RF Cold Crucible Induction Heated Melter with Subsidence (open access)

Modeling an RF Cold Crucible Induction Heated Melter with Subsidence

A method to reduce radioactive waste volume that includes melting glass in a cold crucible radio frequency induction heated melter has been investigated numerically. The purpose of the study is to correlate the numerical investigation with an experimental apparatus that in the above mentioned melter. Unique to this model is the subsidence of the glass as it changes from a powder to molten glass and drastically changes density. A model has been created that couples the magnetic vector potential (real and imaginary) to a transient startup of the melter process. This magnetic field is coupled to the mass, momentum, and energy equations that vary with time and position as the melt grows. The coupling occurs with the electrical conductivity of the glass as it rises above the melt temperature of the glass and heat is generated. Natural convection within the molten glass helps determine the shape of the melt as it progresses in time. An electromagnetic force is also implemented that is dependent on the electrical properties and frequency of the coil. This study shows the progression of the melt shape with time along with temperatures, power input, velocities and magnetic vector potential. Coupled to all of this is a …
Date: July 1, 2004
Creator: Hawkes, Grant L.
Object Type: Article
System: The UNT Digital Library