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(open access)

Electrochemical photovoltaic cells/stabilization and optimization of II-VI semiconductors. First technical progress report, 15 April 1980-30 June 1980

The overall goal of this program is to provide the basis for designing a practical electrochemical solar cell based on the II-VI compound semiconductors. Emphasis is on developing new electrolyte redox systems and electrode surface modifications which will stabilize the II-VI compounds against photodissolution without seriously degrading the long-term solar response. The bulk electrode material properties are also being optimized to provide the maximum solar conversion efficiency and greatest inherent electrode stability. Factors limiting the short circuit current of the n-CdSe/methanol/ferro-ferricyanide system to 17.5 mA/cm/sup 2/ have been identified. The principal limiting factor is apparently specific adsorption of hexacyanoferrate species on the electrode surface which occurs at higher redox couple concentrations and slows the overall charge transfer process. Ion pairing also occurs, resulting in a low mass transport rate (smaller diffusion coefficients and increased solution viscosity), and probably enhances the degree of specific adsorption. Improvements in the performance of this system will require mitigation of the interactions between the redox species and the electrode surface, e.g., via electrolytes with reduced ion-pairing tendencies or the use of electrode surface films. Photoelectrochemically generated polypyrrole films have been shown to protect CdX photoanodes from dissolution while permitting electron exchange with the electrolyte. Current …

Date: July 20, 1980

Creator: Noufi, R.; Tench, D. & Warren, L.

Object Type: Report

System: The UNT Digital Library

(open access)

Extraordinary Light-Trapping Enhancement in Silicon Solar Cell Patterned with Graded Photonic Super-Crystals

This article explores light-trapping enhancement in newly discovered graded photonic super-crystals (GPSCs) with dual periodicity and dual basis.

Date: December 7, 2017

Creator: Hassan, Safaa; Lowell, David; Adewole, Murthada; George, David; Zhang, Hualiang & Lin, Yuankun

Object Type: Article

System: The UNT Digital Library

captions transcript

[News Clip: Pools]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: July 20, 1994, 10:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Eye gouge]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: September 20, 1994, 6:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Parker co courthouse]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: October 20, 1994, 10:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Sikes/Cerelli]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: January 20, 1994, 6:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

(open access)

Temporal perspective on acid deposition research

This statement presented to the Subcommittee on Natural Resources of the US House of Representatives gives a definition of acid rain, presents new data on the regional and temporal nature of the problem, and discusses research needs. (ACR)

Date: February 20, 1980

Creator: Hendrey, George R.

Object Type: Report

System: The UNT Digital Library

(open access)

Site-specific legal and institutional analysis of the barriers to geothermal hydrothermal commercialization present at target prospects in the five Pacific Rim states

The specifics of the permitting process, land access, power plant siting, water law, and other legal or institutional barriers or conflicts are presented for each of the most highly regarded target electric prospects in the five Pacific Rim states: California, Hawaii, Alaska, Oregon, and Wasington. (MHR)

Date: October 20, 1979

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Collector sealants and breathing. Final Report, 25 September 1978-31 December 1979

The objectives of this program were: (1) to investigate the pertinent properties of a variety of possible sealants for solar collectors and identify the most promising candidates, and (2) to study the effect of breathing in flat-plate, thermal solar collector units. The study involved two types of sealants, Class PS which includes preformed seals or gaskets and Class SC which includes sealing compounds or caulks. It was the intent of the study to obtain data regarding initial properties of candidate elastomers from manufacturers and from the technical literature and to use those sources to provide data pertaining to endurance of these materials under environmental service conditions. Where necessary, these data were augmented by experimental measurements. Environmental stresses evaluated by these measurements included elevated temperatures, moisture, ultraviolet light, ozone and oxygen, and fungus. The second major area of the work involved a study of the effects of materials used and design on the durability of solar collectors. Factors such as design, fabrication, materials of construction, seals and sealing techniques and absorber plate coatings were observed on actual field units removed from service. Such phenomena as leakage, corrosion and formation of deposits on glazing and absorber plate were noted. An evaluation of …

Date: February 20, 1980

Creator: Mendelsohn, M A; Luck, R M; Yeoman, F A & Navish, Jr, F W

Object Type: Report

System: The UNT Digital Library

(open access)

The MTX (Microwave Tokamak Experiment) data acquisition system

The diagnostic data from the MTX experiment is acquired and processed by an expandable, distributed, multivendor computer network. The system blends a variety of software into a coordinated, unified, and highly flexible design. Using modular software design techniques, we created a system stressing distributed processing, portability, and transparent data access. In our approach to modularity, we standardized communication interfaces between modules and separated generic tasks from machine and application-specific implementations. For flexible distributed processing, we used modular, portable software and LLNL facility that provides an interprocess communication system (IPCS) in the multivendor network. With transparent data access, any program can access data stored anywhere in the network without knowing the specific location. The computer hardware includes a DEC VAX cluster, HP workstations and HP desktop computers. We are using commercial software in addition to packages from MIT, ORNL, and LLNL. 4 refs., 4 figs.

Date: September 20, 1989

Creator: Butner, D. N.; Drlik, M.; Brown, M. D.; Casper, T. A.; Meyer, W. H. & Moller, J. M.

Object Type: Article

System: The UNT Digital Library

(open access)

State water rights law and geothermal hydrothermal commercialization in five Pacific Rim states

The water rights of the five Pacific states - California, Oregon, Washington, Alaska, and Hawaii - and their possible impacts on geothermal development are discussed. (MHR)

Date: March 20, 1980

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

GENERAL STANDARDS GUIDE FOR EXPERIMENTS IN ORNL RESEARCH REACTORS

The Oak Ridge National Laboratory has three generalpurpose research reactors which accommodate testing loops, target irradiations, and beam-type experiments. Since the experiments must share common or similar facilities and utilities, be designed and fabricated by the same groups, and meet the safe safety criteria, certain standards for these have been developed. These standards deal only with those properties from which safety and economy of time and money can be maximized and do not relate to the intent of the experiment or quality of the data obtained. The necessity for, and the limitations of, the standards are discussed; and a compilation of general standards is included. (auth)

Date: August 20, 1962

Creator: Cagle, C.D.

Object Type: Report

System: The UNT Digital Library

(open access)

Development of Passive Electronic Components for Instrumentation of Improved Geothermal Logging Tools and Components. Semiannual Progress Report. Report No. 1. [For Temperatures Up to 500/sup 0/C]

Research progress is reported on the development of passive components, resistors, capacitors, metallization, and passivation, that will withstand well logging temperatures to 500/sup 0/C and have extremely low temperature coefficients. The lower the temperature coefficients, the more exacting the instrumentation designs can be without elaborate compensation techniques. The method of fabricating the thin film components is that of chemical vapor deposition (CVD) which is a major deviation from the standard approach. The films are grown in a CVD reactor by passing various reactant gases over a heated substrate. The reactor was modified in order to accommodate the gases needed in the deposition of metals. The reactor can be operated over a temperature range of 400/sup 0/C to greater than 1200/sup 0/C, and at any pressure between atmospheric and 1 x 10/sup -3/ torr. Tungsten, tungsten-silicon, and silicon nitride were successfully deposited on oxidized silicon wafers. The tungsten is used for interconnects and capacitor plates, tungsten-silicon is used as a high resistivity material for resistors, and silicon nitride is used as a dielectric for the capacitors and as a passivation layer. The materials are currently being studied in terms of their deposition parameters and electrical characteristics.

Date: April 20, 1977

Creator: Raymond, L. S.; Hamilton, D. J. & Kerwin, W. J.

Object Type: Report

System: The UNT Digital Library

(open access)

Materials testing using laser energy deposition

A convenient method for determining the elastic constants of materials has been devised using the energy from a Q-switched neodymium-glass laser. Stress waves are induced in materials having circular rod or rectangular bar geometries by the absorption of energy from the laser. The wave transit times through the material are recorded with a piezoelectric transducer. Both dilatation and shear wave velocities are determined in a single test using an ultrasonic technique and these velocities are used to calculate the elastic constants of the material. A comparison of the constants determined for ten common engineering materials using this method is made with constants derived using the conventional ultrasonic pulse technique and agreement is shown to be about one percent in most cases. Effects of material geometry are discussed and surface damage to the material caused by laser energy absorption is shown.

Date: December 20, 1977

Creator: Wilcox, W.W. & Calder, C.A.

Object Type: Article

System: The UNT Digital Library

(open access)

Lid Tank Shielding Facility Measurements Behind the ML-1 Mockup

An experimental evaluation of the shield design for the ML-1 mobile reactor was made at the Lid Tank Shielding Facility. Thermal-neutron fluxes, fast-neutron dose rates, and gamma-ray dose rates were measured behind slab mockups of the basic shield design and a number of possible variations. The designs embodied various combinations of lead, Hevimet, stainless steel, boral, water, and aqueous solutions of ammonium pentaborate at two concentrations. The after-shutdown decay characteristics of the basic design were determined, and data were obtained from a fairly accurate mockup of the stainless steel plenum and gas duct typical of the top and bottom regions of the ML-1 shield. Analysis of results and application to the final shield design are not reported. (auth)

Date: September 20, 1961

Creator: MacKellar, A. D.; Jung, L.; Mathews, D. R.; Muckenthaler, F. J.; Miller, J. M. & Sowards, N. K.

Object Type: Report

System: The UNT Digital Library

(open access)

Site 300 hazardous-waste-assessment project. Interim report: December 1981. Preliminary site reconnaissance and project work plan

This document was prepared to outline the scope and objectives of the Hazardous Waste Assessment Project (HWAP) at Site 300. This project was initiated in October, 1981, to investigate the existing solid waste landfills in an effort to satisfy regulatory guidelines and assess the potential for ground-water contamination. This involves a site-specific investigation (utilizing geology, hydrology, geophysics and geochemistry) with the goal of developing an effective ground-water quality monitoring network. Initial site reconnaissance work has begun and we report the results, to date, of our geologic hydrogeologic studies. All known solid waste disposal locations are underlain by rocks of either the Late Miocene Neroly Formation or the Cierbo Formation, both of which are dominantly sandstones interbedded with shale and claystone. The existence of a regional confined (artesian) aquifer, as well as a regional water-table aquifer is postulated for Site 300. Preliminary analysis has led to an understanding of directions and depths of regional ground-water flow.

Date: January 20, 1982

Creator: Raber, E.; Helm, D.; Carpenter, D.; Peifer, D. & Sweeney, J.

Object Type: Report

System: The UNT Digital Library

(open access)

Automatic voltage-imbalance detector

A device is described for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

Date: May 20, 1981

Creator: Bobbett, R. E.; McCormick, J. B. & Kerwin, W. J.

Object Type: Patent

System: The UNT Digital Library

(open access)

Selective emitter. Task II topical report for radiative-cooling materials

The theoretical basis of the selective emitter is that, if a material emits only in the 8-13 micron interval, it will absorb only in the same interval. After a survey of several candidate materials, the silicon oxynitride system was found to have better optical properties than previously used materials as well as economic feasibility, and efforts to acquire a sample are described. Other promising materials are described: polyvinylidene fluoride (Tedlar), silicon monoxide, silicon dioxide, and silicon nitride. (LEW)

Date: September 20, 1981

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Program RELAX: A code designed to calculate atomic relaxation spectra of x-rays and electrons

The code RELAX is designed to calculate atomic relaxation spectra of X-rays and electrons due to bound-bound transitions. This calculation is based on the atomic transition data contained in the Livermore Evaluated Atomic Data Library (EADL). The results produced by this code for fluorescence yield vs. atomic number (Z) have been published in Tables and Graphs of Atomic Subshell and Relaxation Data Derived from the LLNL Evaluated Atomic Data Library (EADL), z = 1--100{double prime}, UCRL-50400, Vol. 30, October 31, 1991, Lawrence Livermore National Laboratory.

Date: March 20, 1992

Creator: Cullen, D.E.

Object Type: Report

System: The UNT Digital Library

(open access)

Monopole search using an accelerator detector

A neutrino detector at the Brookhaven AGS has been used to investigate the feasibility of using an already constructed apparatus for GUT monopole searches. A flux limit (90%CL) of 5.2 x 10/sup -12/ cm/sup -2/ sec/sup -1/ str/sup -1/ was found. The limitations of such an approach are discussed.

Date: December 20, 1983

Creator: Ahrenes, L.A.; Aronson, S.H.; Connolly, P.L.; Erickson, T.E.; Gibbard, B.G.; Montag, M. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Knowledges and abilities catalog for nuclear power plant operators: Savannah River Site (SRS) production reactors

The Knowledges and Abilities Catalog for Nuclear Power Plant Operations: Savannah River Site (SRS) Production Reactors, provides the basis for the development of content-valid certification examinations for Senior Reactor Operators (SROs) and Central Control Room Supervisors (SUP). The position of Shift Technical Engineer (STE) has been included in the catalog for completeness. This new SRS reactor operating shift crew position is held by an individual holding a CCR Supervisor Certification who has received special engineering and technical training. Also, the STE has a Bachelor of Science degree in engineering or a related technical field. The SRS catalog contains approximately 2500 knowledge and ability (K/A) statements for SROs and SUPs at heavy water moderated production reactors. Each K/A statement has been rated for its importance to the safe operation of the plant in a manner ensuring the health and safety of the public. The SRS K/A catalog is presently organized into five major sections: Plant Systems grouped by Safety Function, Plant Wide Generic K/As, Emergency Plant Evolutions, Theory and Components (to be developed).

Date: June 20, 1990

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Fusion product deposition and energy balance

Extensive Monte-Carlo calculations were performed of alpha-particle deposition in the Hill's Vortex configuration, as reported in D.E. Driemeyer's Ph.D. Thesis (University of Illinois, 1980). This has generally been done including a cold plasma density, n/sub c/, on the open field lines, with n/sub C//T/sub C//sup 3/2/ approx. = n/sub H//T/sub H//sup 3/2/ - i.e. with the slowing down ratio tau/sub H//tau/sub C/ lying between .1 and 10. Since many of the alpha particles spend a significant amount of their time on the open field lines, values of tau/sub H//tau/sub C/ greater than unity lead to significant removal of alpha-particle ash from the closed-field region. Surprisingly, one is able to perform this ash removal and still retain enough energy to raise the reactor Q significantly (or even ignite it).

Date: May 20, 1980

Creator: Condit, W.C. & Driemeyer, D.E.

Object Type: Report

System: The UNT Digital Library

(open access)

Comparison of the initial ETA gas propagation experiments with theoretical models

This report contains a description of the initial ETA propagation experiments in air at a beam current of 4.5 kA. The beam was observed to propagate at the pressures anticipated on the basis of previous theory and experiment. A comparison of measured net current waveforms with predictions of the PHOENIX code showed good agreement over the pressure range 0.1 to 200 torr. However, the beam was observed to expand with Z at a faster rate than theory predicts. Excessive transverse beam modulation at injection complicated the experiments and limited their comparison with theory.

Date: April 20, 1982

Creator: Chambers, F. W.; Clark, J. C. & Fessenden, T. J.

Object Type: Report

System: The UNT Digital Library

(open access)

Catalogue of monitoring activities at Rocky Flats: 1978, 1979

A listing of environmental surveillance sampling endeavors for the years 1978 and 1979 is given in which sampling media, i.e., ambient air, stack effluent air, water, and soil are considered. Sampling locations, frequency of sampling, parameters analyzed, and control limits also are given. The objectives of the sampling are considered in defining the program.

Date: June 20, 1980

Creator: Werkema, M. V.

Object Type: Report

System: The UNT Digital Library

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