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Using Cytochrome c{sub 3} to Make Selenium Nanowires
We report on a new method to make nanostructures, in this case selenium nanowires, in aqueous solution at room temperature. We used the protein cytochrome c{sub 3} to reduce selenate (SeO{sub 4}{sup 2{minus}}) to selenium (Se{sup 0}). Cytochrome c{sub 3} is known for its ability to catalyze reduction of metals including U{sup VI} {yields} U{sup IV}, Cr{sup VI} {yields} Cr{sup III}, Mo{sup VI} {yields} Mo{sup IV}, Cu{sup II} {yields} Cu{sup 0}, Pb{sup II} {yields} Pb{sup 0}, Hg{sup II} {yields} Hg{sup 0}. Nanoparticles of Se{sup 0} precipitated from an aqueous solution at room temperature, followed by spontaneous self-assembling into nanowires. Cytochrome c{sub 3} was extracted from the sulfate-reducing bacteria Desulfovibrio vulgaris (strain Holdenborough) and isolated by the procedure of DerVartanian and Legall.
Date:
November 24, 1999
Creator:
Abdelouas, A.; Franco, R.; Gong, W. L.; Lutze, W.; Moura, I. & Shelnutt, John A.
Object Type:
Article
System:
The UNT Digital Library
Depth Measurement of Moving Slurry at the Wet End of a Paper Machine
The paper industry has long had a need to better understand and control its papermaking process upstream, specifically at the wet end in the forming section of a paper machine. A vision-based system is under development that addresses this need by automatically measuring and interpreting the pertinent paper web parameters at the wet end in real time. The wet-end characterization of the paper web by a vision system involves a four-dimensional measurement of the slurry in real time. These measurements include the two-dimensional spatial information, the intensity profile, and the depth profile. This paper describes the real-time depth profile measurement system for the high-speed moving slurry. A laser line-based measurement method is used with a high-speed programmable camera to directly measure slurry height. The camera is programmed with a profile algorithm, producing depth data at fast sampling rates. Analysis and experimentation have been conducted to optimize the system for the characteristics of the slurry and laser line image. On-line experimental results are presented.
Date:
January 24, 1999
Creator:
Abidi, B. R.; Goddard, J. S., Jr.; Hunt, M. A.; Sari-Sarraf, H. & Turner, J. C.
Object Type:
Article
System:
The UNT Digital Library
Year 2000 TWRS Maintenance procedure review report
A concern exists that some equipment in use might contain microprocessors that are dependent upon a time date function. The majority of the software programming for microprocessors has only utilized a 2 digit identifier for the year. With the approach of the year 2000, (Y2K), there is concern that the date function will not be correctly recognized and some functions will not operate properly. TWRS maintenance procedures have been reviewed to identify equipment components that may not be Y2K compliant. Engineering judgment was utilized to eliminate procedures and equipment that is obviously not impacted by Y2K.
Date:
February 24, 1999
Creator:
Adams, M. R.
Object Type:
Report
System:
The UNT Digital Library
PARTICLE TRANSPORT AND DEPOSITION IN THE HOT-GAS FILTER AT WILSONVILLE
Particle transport and deposition in the Wilsonville hot-gas filter vessel is studied. The filter vessel contains a total of 72 filters, which are arranged in two tiers. These are modeled by six upper and one lower cylindrical effective filters. An unstructured grid of 312,797 cells generated by GAMBIT is used in the simulations. The Reynolds stress model of FLUENT{trademark} (version 5.0) code is used for evaluating the gas mean velocities and root mean-square fluctuation velocities in the vessel. The particle equation of motion includes the drag, the gravitational and the lift forces. The turbulent instantaneous fluctuation velocity is simulated by a filtered Gaussian white-noise model provided by the FLUENT code. The particle deposition patterns are evaluated, and the effect of particle size is studied. The effect of turbulent dispersion, the lift force and the gravitational force are analyzed. The results show that the deposition pattern depends on particle size. Turbulent dispersion plays an important role in transport and deposition of particles. Lift and gravitational forces affect the motion of large particles, but has no effect on small particles.
Date:
June 24, 1999
Creator:
Ahmadi, Goodarz
Object Type:
Report
System:
The UNT Digital Library
Synthesis, Characterization, and Catalytic Activity of Sulfided Silico-Alumino-Titanate (Si-Al-Ti) Mixed Oxides Xerogels Supported Ni-Mo Catalyst
Layered semicrystalline silico-alumino-titanate (Si-Al-Ti) mixed oxides were synthesized by a modified sol-gel method with hydrothermal synthesis temperatures less than 200 C and autogenic pressure. The solid products are semicrystalline materials with a surface area of 136-367 m{sup 2}/g and a monomodal pore size distribution with an average pore diameter of 3.6-4.7 nrn. The catalytic activity for pyrene hydrogenation in a batch reactor at 300 C and 500 psig was determined for sulfided Ni-Mo supported on the Si-Al-Ti mixed oxide. The activity was a function of the support composition the heat treatment before and after loading the active metals, the addition of organic templates, and different methods of metal loading. The most active sulfided Ni-Mo/Si-Al-Ti catalyst has an activity in the same range as the commercial catalyst, Shell 324, but the metal loading is 37% less than the commercial catalyst.
Date:
February 24, 1999
Creator:
Al-Adwani, H. A.; Anthony, R. G.; Gardner, T. J. & Thammachote, N.
Object Type:
Article
System:
The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 112, Ed. 1 Wednesday, February 24, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
February 24, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
TFA FY00-FY04 Multiyear Program Plan
This multiyear program plan (MYPP) reflects the TFA's plan for the next five fiscal years (FY00-FY04). Most of the planning emphasis is on FY00 and FY01.
Date:
August 24, 1999
Creator:
Allen, Robert W.; Brouns, Thomas M.; Carteret, Betty A.; Gilchrist, Roger L.; Schlahta, Stephan N.; Westsik, Joseph H. et al.
Object Type:
Report
System:
The UNT Digital Library
Modeling Manufacturing Processes to Mitigate Technological Risk
An economic model is a tool for determining the justifiable cost of new sensors and subsystems with respect to value and operation. This process balances the R and D costs against the expense of maintaining current operations and allows for a method to calculate economic indices of performance that can be used as control points in deciding whether to continue development or suspend actions. The model can also be used as an integral part of an overall control loop utilizing real-time process data from the sensor groups to make production decisions (stop production and repair machine, continue and warn of anticipated problems, queue for repairs, etc.). This model has been successfully used and deployed in the CAFE Project. The economic model was one of seven (see Fig. 1) elements critical in developing an investment strategy. It has been successfully used in guiding the R and D activities on the CAFE Project, suspending activities on three new sensor technologies, and continuing development o f two others. The model has also been used to justify the development of a new prognostic approach for diagnosing machine health using COTS equipment and a new algorithmic approach. maintaining current operations and allows for a method …
Date:
October 24, 1999
Creator:
Allgood, G. O. & Manges, W. W.
Object Type:
Article
System:
The UNT Digital Library
Lifetime measurements and dipole transition rates for superdeformed states in {sup 190}Hg.
The Doppler-shift attenuation method was used to measure life-times of superdeformed (SD) states for both the yrast and the first excited superdeformed band of {sup 190}Hg. Intrinsic quadruple moments Q{sub 0} were extracted. For the first time, the dipole transition rates have been extracted for the inter-band transitions which connect the excited SD band to the yrast states in the second minimum. The results support the interpretation of the excited SD band as a rotational band built on an octupole vibration.
Date:
March 24, 1999
Creator:
Amro, H.
Object Type:
Article
System:
The UNT Digital Library
Anisotropic Magnetism in Field-Structured Composites
Magnetic field-structured-composites (FSCs) are made by structuring magnetic particle suspensions in uniaxial or biaxial (e.g. rotating) magnetic fields, while polymerizing the suspending resin. A uniaxial field produces chain-like particle structures, and a biaxial field produces sheet-like particle structures. In either case, these anisotropic structures affect the measured magnetic hysteresis loops, with the magnetic remanence and susceptibility increased significantly along the axis of the structuring field, and decreased slightly orthogonal to the structuring field, relative to the unstructured particle composite. The coercivity is essentially unaffected by structuring. We present data for FSCs of magnetically soft particles, and demonstrate that the altered magnetism can be accounted for by considering the large local fields that occur in FSCs. FSCS of magnetically hard particles show unexpectedly large anisotropies in the remanence, and this is due to the local field effects in combination with the large crystalline anisotropy of this material.
Date:
June 24, 1999
Creator:
Anderson, Robert A.; Martin, James E.; Odinek, Judy & Venturini, Eugene
Object Type:
Article
System:
The UNT Digital Library
Data Management Guide for FEMIS Version 1.4.6
This FEMIS Data Management Guide provides the information needed to manage the data used to support the administrative, user-environment, database management, and operational capabilities of FEMIS.
Date:
June 24, 1999
Creator:
Angel, Linda K.; Bower, John C.; Burnett, Robert A.; Downing, Timothy R.; Fangman, Patricia M.; Hoza, Mark et al.
Object Type:
Report
System:
The UNT Digital Library
Coupled mechanical/heat transfer simulation on MPP platforms using a finite element/linear solver interface
This report describes the implementation of a coupled mechanical /heat transfer simulation using a Finite Element Interface (FEI). The FE1 is an abstraction layer, which lies between the application code and its linear solver libraries, controlling the set-up and solution of the linear system arising in the finite element simulation. The performance and scalability of the ISIS++ FE1 is examined on the ASCI Red and Blue machines in the context of the ALE3D finite element simulation code.
Date:
February 24, 1999
Creator:
Aro, C J; Dube, E I & Futral, W S
Object Type:
Article
System:
The UNT Digital Library
System Administration Guide for FEMIS Version 1.4.6
The FEMIS System Administration Guide provides information on FEMIS System Administrator activities as well as the utilities that are included with FEMIS.
Date:
June 24, 1999
Creator:
Arp, Jonathan A.; Bower, John C.; Burnett, Robert A.; Carter, Richard J.; Downing, Timothy R.; Fangman, Patricia M. et al.
Object Type:
Report
System:
The UNT Digital Library
Magnetic Semiconductor Quantum Wells in High Fields to 60 Tesla: Photoluminescence Linewidth Annealing at Magnetization Steps
Magnetic semiconductors offer a unique possibility for strongly tuning the intrinsic alloy disorder potential with applied magnetic field. We report the direct observation of a series of step-like reductions in the magnetic alloy disorder potential in single ZnSe/Zn(Cd,Mn)Se quantum wells between O and 60 Tesla. This disorder, measured through the linewidth of low temperature photoluminescence spectra drops abruptly at -19, 36, and 53 Tesla, in concert with observed magnetization steps. Conventional models of alloy disorder (developed for nonmagnetic semiconductors) reproduce the general shape of the data, but markedly underestimate the size of the linewidth reduction.
Date:
May 24, 1999
Creator:
Awschalom, D.D.; Crooker, S.A.; Lyo, S.K.; Rickel, D.G. & Samarth, N.
Object Type:
Article
System:
The UNT Digital Library
SNF fuel retrieval sub project safety analysis document
This safety analysis is for the SNF Fuel Retrieval (FRS) Sub Project. The FRS equipment will be added to K West and K East Basins to facilitate retrieval, cleaning and repackaging the spent nuclear fuel into Multi-Canister Overpack baskets. The document includes a hazard evaluation, identifies bounding accidents, documents analyses of the accidents and establishes safety class or safety significant equipment to mitigate accidents as needed.
Date:
February 24, 1999
Creator:
BERGMANN, D.W.
Object Type:
Report
System:
The UNT Digital Library
Tank waste remediation system nuclear criticality safety program management review
This document provides the results of an internal management review of the Tank Waste Remediation System (TWRS) criticality safety program, performed in advance of the DOE/RL assessment for closure of the TWRS Nuclear Criticality Safety Issue, March 1994. Resolution of the safety issue was identified as Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-40-12, due September 1999.
Date:
June 24, 1999
Creator:
BRADY RAAP, M.C.
Object Type:
Report
System:
The UNT Digital Library
Double-shell tank emergency pumping guide
This Double-Shell Tank Emergency Pumping Guide provides the preplanning necessary to expeditiously remove any waste that may leak from the primary tank to the secondary tank for Hanford's 28 DSTS. The strategy is described, applicable emergency procedures are referenced, and transfer routes and pumping equipment for each tank are identified.
Date:
February 24, 1999
Creator:
BROWN, M.H.
Object Type:
Report
System:
The UNT Digital Library
Challenges in the Packaging of MEMS
Microelectromechanical Systems (MEMS) packaging is much different from conventional integrated circuit (IC) packaging. Many MEMS devices must interface to the environment in order to perform their intended function, and the package must be able to facilitate access with the environment while protecting the device. The package must also not interfere with or impede the operation of the MEMS device. The die attachment material should be low stress, and low outgassing, while also minimizing stress relaxation overtime which can lead to scale factor shifts in sensor devices. The fabrication processes used in creating the devices must be compatible with each other, and not result in damage to the devices. Many devices are application specific requiring custom packages that are not commercially available. Devices may also need media compatible packages that can protect the devices from harsh environments in which the MEMS device may operate. Techniques are being developed to handle, process, and package the devices such that high yields of functional packaged parts will result. Currently, many of the processing steps are potentially harmful to MEMS devices and negatively affect yield. It is the objective of this paper to review and discuss packaging challenges that exist for MEMS systems and to …
Date:
September 24, 1999
Creator:
BROWN, WILLIAM D.; EATON, WILLIAM P.; MALSHE, AJAY P.; MILLER, WILLIAM M.; O'NEAL, CHAD & SINGH, SUSHILA B.
Object Type:
Article
System:
The UNT Digital Library
Project W-211 initial tank retrieval systems year 2000 compliance assessment project plan
This assessment describes the potential Year 2000 (Y2K) problems and describes the methods for achieving Y2K Compliance for Project W-211, Initial Tank Retrieval Systems (ITRS). The purpose of this assessment is to give an overview of the project. This document will not be updated and any dates contained in this document are estimates and may change. The scope of project W-211 is to provide systems for retrieval of radioactive wastes from ten double-shell tanks (DST). systems will be installed in tanks 102-AP, 104-AP, 105-AN, 104-AN, 102-AZ, 101-AW, 103-AN, 107-AN, 102-AY, and 102-SY. The current tank selection and sequence supports phase I feed delivery to privatized processing plants. A detailed description of system dates, functions, interfaces, potential Y2K problems, and date resolutions can not be described since the project is in the definitive design phase. This assessment will describe the methods, protocols, and practices to assure that equipment and systems do not have Y2K problems.
Date:
August 24, 1999
Creator:
BUSSELL, J.H.
Object Type:
Report
System:
The UNT Digital Library
Thermo-Chemical-Mechanical Effects on Microstructure Development in Low-Alloy Steel Welds
Effect of aluminum on the decomposition of 5 ferrite to austenite was investigated in a low-alloy steel weld. In addition, the effect of inclusion composition on the transition from bainite to acicular ferrite during austenite decomposition was analyzed. Stress relaxation during decomposition of austenite to allotriomorphic and acicular ferrite was also characterized. Results from the above experiments illustrate the importance of thermomechanical effects on weld microstructure evolution.
Date:
May 24, 1999
Creator:
Babu, S.S.; David, S.A. & Vitek, J.M.
Object Type:
Article
System:
The UNT Digital Library
Project W-030 flammable gas verification monitoring test
This document describes the verification monitoring campaign used to document the ability of the new ventilation system to mitigate flammable gas accumulation under steady state tank conditions. This document reports the results of the monitoring campaign. The ventilation system configuration, process data, and data analysis are presented.
Date:
February 24, 1999
Creator:
Barker, S. A.
Object Type:
Report
System:
The UNT Digital Library
News Bulletin (Castroville, Tex.), Vol. 41, No. 25, Ed. 1 Thursday, June 24, 1999
Weekly newspaper from Castroville, Texas that includes local, state, and national news along with extensive advertising.
Date:
June 24, 1999
Creator:
Barnes, Thomas
Object Type:
Newspaper
System:
The Portal to Texas History
A Pulse Power Modulator System for Commercial High Power Ion Beam Surface Treatment Applications
The Ion Beam Surface Treatment (lBESTrM) process utilizes high energy pulsed ion beams to deposit energy onto the surface of a material allowing near instantaneous melting of the surface layer. The melted layer typically re-solidifies at a very rapid rate which forms a homogeneous, fine- grained structure on the surface of the material resulting in significantly improved surface characteristics. In order to commercialize the IBESTTM process, a reliable and easy-to-operate modulator system has been developed. The QM-I modulator is a thyratron-switched five-stage magnetic pulse compression network which drives a two-stage linear induction adder. The adder provides 400 kV, 150 ns FWHM pulses at a maximum repetition rate of 10 pps for the acceleration of the ion beam. Special emphasis has been placed upon developing the modulator system to be consistent with long-life commercial service.
Date:
May 24, 1999
Creator:
Barrett, D. M.; Cockreham, B.D.; Dragt, A. J.; Ives, H. C.; Neau, E. L.; Reed, K. W. et al.
Object Type:
Article
System:
The UNT Digital Library
EPA's Tier 2 Proposal for Stricter Vehicle Emission Standards: A Fact Sheet
The Clean Air Act Amendments of 1990 established "Tier 1" standards to limit tailpipe emissions from new motor vehicles, and the Environmental Protection Agency (EPA) is required to determine if more stringent requirements are needed to attain or maintain National Ambient Air Quality Standards. EPA also must assess the availability and cost-effectiveness of technologies necessary to control emissions. In a report submitted to Congress in August 1998, EPA concluded that tougher standards are necessary and that essential technologies are available and cost-effective
Date:
June 24, 1999
Creator:
Bearden, David M.
Object Type:
Report
System:
The UNT Digital Library