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Cationically polymerizable monomers derived from renewable sources
The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. Their photopolymerization was carried out using cationic photoinitiators and the mechanical properties of the resulting polymers characterized. Preliminary biodegradation studies are being conducted on the photopolymerized films from several of these oils. Limonene was cationically polymerized to give dimers and the dimers epoxidized to yield highly reactive monomers suitable for coatings, inks and adhesives. The direct phase transfer epoxidation of squalene and natural rubber was carried out. The modified rubbers undergo facile photocrosslinking in the presence of onium salts to give crosslinked elastomers. 12 refs., 3 figs., 10 tabs.
Date:
October 1, 1991
Creator:
Crivello, J. V.
Object Type:
Report
System:
The UNT Digital Library
Ceramic technology for Advanced Heat Engines Project
Significant accomplishments in fabricating ceramic components for advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and database and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a five year project plan was developed with extensive input from private industry. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. This project is managed by ORNL for the Office …
Date:
July 1, 1991
Creator:
Johnson, D. R.
Object Type:
Report
System:
The UNT Digital Library
(Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)
An environmental investigation of ground water conditions has been undertaken at Wright-Patterson Air Force Base (WPAFB), Ohio to obtain data to assist in the evaluation of a potential removal action to prevent, to the extent practicable, migration of the contaminated ground water across Base boundaries. Field investigations were limited to the central section of the southwestern boundary of Area C and the Springfield Pike boundary of Area B. Further, the study was limited to a maximum depth of 150 feet below grade. Three primary activities of the field investigation were: (1) installation of 22 monitoring wells, (2) collection and analysis of ground water from 71 locations, (3) measurement of ground water elevations at 69 locations. Volatile organic compounds including trichloroethylene, perchloroethylene, and/or vinyl chloride were detected in concentrations exceeding Maximum Contaminant Levels (MCL) at three locations within the Area C investigation area. Ground water at the Springfield Pike boundary of Area B occurs in two primary units, separated by a thicker-than-expected clay layers. One well within Area B was determined to exceed the MCL for trichloroethylene.
Date:
March 1, 1992
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory
This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. It is not to be inferred that these methods are universal for any type of sample, but they have been found very reliable for the types of samples mentioned.
Date:
August 1, 1991
Creator:
Greulich, K. A. & Gray, C. E.
Object Type:
Report
System:
The UNT Digital Library
Surfaces and Thin Films Studied by Picosecond Ultrasonics
This research is the study of thin films and interfaces via the use of the picosecond ultrasonic technique. In these experiments ultrasonic waves are excited in a structure by means of a picosecond light pulse ( pump pulse''). The propagation of these waves is detected through the use of a probe light pulse that is time-delayed relative to the pump. This probe pulse measures the change {Delta}R(t) in the optical reflectivity of the structure that occurs because the ultrasonic wave changes the optical properties of the structure. This technique make possible the study of the attenuation and velocity of ultrasonic waves up to much higher frequencies than was previously possible (up to least 500 GHz). In addition, the excellent time-resolution of the method makes it possible to study nanostructures of linear dimensions down to 100 {Angstrom} or less by ultrasonic pulse-echo techniques. 25 refs.
Date:
May 1, 1992
Creator:
Maris, J. H. & Tauc, J.
Object Type:
Report
System:
The UNT Digital Library
Westinghouse Hanford Company waste minimization and pollution prevention awareness program plan
The purpose of this plan is to establish the Westinghouse Hanford Company's Waste Minimization Program. The plan specifies activities and methods that will be employed to reduce the quantity and toxicity of waste generated at Westinghouse Hanford Company (Westinghouse Hanford). It is designed to satisfy the US Department of Energy (DOE) and other legal requirements that are discussed in Subsection C of the section. The Pollution Prevention Awareness Program is included with the Waste Minimization Program as permitted by DOE Order 5400.1 (DOE 1988a). This plan is based on the Hanford Site Waste Minimization and Pollution Prevention Awareness Program Plan, which directs DOE Field Office, Richland contractors to develop and maintain a waste minimization program. This waste minimization program is an organized, comprehensive, and continual effort to systematically reduce waste generation. The Westinghouse Hanford Waste Minimization Program is designed to prevent or minimize pollutant releases to all environmental media from all aspects of Westinghouse Hanford operations and offers increased protection of public health and the environment. 14 refs., 2 figs., 1 tab.
Date:
August 1, 1991
Creator:
Craig, P.A.; Nichols, D.H. & Lindsey, D.W.
Object Type:
Report
System:
The UNT Digital Library
Molecular interactions in dilute supercritical mixtures: Molecular dynamics investigation
We performed a series of molecular dynamics simulations aimed at investigating the nature of the microstructure around solute molecules in a supercritical solvent, in the limit of infinite dilution (no solute-solute interactions). The choice of model system (pyrene in supercritical carbon dioxide) and state conditions (5--20 moles/liter; 37{degrees}C and 75{degrees}C) was done so as to match corresponding fluorescence experiments performed at Georgia Tech. 18 refs., 3 figs.
Date:
January 1, 1991
Creator:
Debenedetti, P.G.
Object Type:
Report
System:
The UNT Digital Library
Particle production and spectra in E802 at BNL-AGS
The production of {pi}, K, and protons measured in the E802 spectrometer are studied for p+A and Si+A collisions. Systematic properties of particle spectra and rapidity density distributions are discussed in terms of centrality and reaction system. A detailed comparison of the data to the RQMD model, which employs the experimental acceptance and cuts are presented. 8 refs., 6 figs.
Date:
January 1, 1991
Creator:
Videbaek, F.
Object Type:
Article
System:
The UNT Digital Library
An update on environmental, health and safety issues of interest to the photovoltaic industry
There is growing interest in the environmental, health, and safety issues related to new photovoltaic technologies as they approach commercialization. Such issues include potential toxicity of II--VI compounds; the impacts of new environmental regulations on module manufacturers; and, the need for recycling of spent modules and manufacturing wastes. This paper will review these topics. 20 refs.
Date:
January 1, 1992
Creator:
Moskowitz, P. D.; Viren, J. & Fthenakis, V. M.
Object Type:
Article
System:
The UNT Digital Library
X-ray, soft x-ray, and vuv beam position monitor
An x-ray beam position monitor has been developed and is currently operational at the NIST beamline X-24A of the National Synchrotron Light Source, Upton, NY. It was developed to accurately measure the vertical position of the synchrotron beam and to allow precise positioning of beamline optics. It is an area type monitor positioned 5.6 meters from the Tangent Point and precedes all beamline instrumentation. Vertical beam position is given by the differential photoemission current from two grids mounted on a Macor frame. The monitor also senses the total photon beam flux. 7 refs., 4 figs.
Date:
January 1, 1991
Creator:
Karlin, B.A. (Brookhaven National Lab., Upton, NY (United States)); Cowan, P.L. (Argonne National Lab., IL (United States)) & Woicik, J.C. (National Inst. of Standards and Technology (IMSE), Gaithersburg, MD (United States))
Object Type:
Article
System:
The UNT Digital Library
A design of experiment study of plasma sprayed alumina-titania coatings
An experimental study of the plasma spraying of alumina-titania powder is presented in this paper. This powder system is being used to fabricate heater tubes that emulate nuclear fuel tubes for use in thermal-hydraulic testing. Coating experiments were conducted using a Taguchi fractional-factorial design parametric study. Operating parameters were varied around the typical spray parameters in a systematic design of experiments in order to display the range of plasma processing conditions and their effect on the resultant coating. The coatings were characterized by hardness and electrical tests, image analysis, and optical metallography. Coating qualities are discussed with respect to dielectric strength, hardness, porosity, surface roughness, deposition efficiency, and microstructure. The attributes of the coatings are correlated with the changes in operating parameters.
Date:
January 1, 1992
Creator:
Steeper, T. J. (Du Pont de Nemours (E.I.) and Co., Aiken, SC (United States). Savannah River Lab.); Varacalle, D. J. Jr.; Wilson, G. C. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Riggs, W. L. II (Tubal Cain Co., Loveland, OH (United States)); Rotolico, A. J. & Nerz, J. E. (Metco/Perkin-Elmer, Westbury, NY (United States))
Object Type:
Article
System:
The UNT Digital Library
Writer's Guide for technical procedures
A primary objective throughout the Department of Energy (DOE) complex is that operations be conducted in a deliberate and controlled manner with emphasis upon recognition and maintenance of the facility-specific safety envelope. One critical element of maintaining the safety envelope is procedures. DOE is providing guidance through this and other writer's guides to assist procedure writers across the DOE complex in producing accurate, complete, and usable procedures that promote safe and efficient operations in keeping with such DOE Orders as 5480.19, Conduct of Operations for DOE Facilities'', 5480.5, Safety of Nuclear facilities'', and 5480.6, Safety of Department of Energy-Owned Nuclear Reactors''. This Writer's Guide addresses the content, format, and style of technical procedures (procedures that prescribe production, operation of equipment and facilities, and maintenance activities) and is intended to be applied in a manner appropriate to the individual facility, 15 refs.
Date:
September 1, 1991
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Structural analysis of the central Columbia Plateau utilizing radar, digital topography, and magnetic data bases
Interest in the Hanford site (Washington) as a nuclear production, power, and waste disposal site has led to generation of a vast quantity of geophysical and remote sensing data sets of the central Columbia Plateau. To data, these various studies, including at least 13 independent magnetic linear and image lineament studies, have not been adequately correlated. Therefore, these studies provide a unique opportunity to compare and contrast the viability of the different geophysical and remote sensing techniques. The geology of the central Columbia Plateau is characterized by subdued topography and limited outcrop, with most of the exposure concentrated in localized folded/faulted mountains (the Yakima folds) and along river canyons. In order to efficiently compare lineament data bases, we have written an automated computer routine that correlated lineaments that are within a user specified distance of each other. The angle between their trends has to be less than an input maximum separation angle. If more than two lineament maps exist for the area, the analyst may also specify the minimum number of times each structure must be seen. The lineament correlation routine was applied to data bases of all aeromagnetic linears as well as lineaments seen on radar and a digital …
Date:
August 1, 1991
Creator:
Thiessen, R. L.; Eliason, J. R.; Johnson, L. K.; Brougher, C. W. (Washington State Univ., Pullman, WA (United States). Dept. of Geology); Foley, M. G. & Beaver, D. E. (Pacific Northwest Lab., Richland, WA (United States))
Object Type:
Article
System:
The UNT Digital Library
Theoretical study of the structure, energetics, and dynamics of silicon and carbon systems using tight-binding approaches
Semiempirical interatomic potentials are developed for silicon and carbon by modeling the total energy of the system using tight-binding approaches. The parameters of the models were obtained by fitting to results from accurate first-principles Local Density Functional calculations. Applications to the computation of phonons as a function of volume for diamond-structured silicon and carbon and the thermal expansions for silicon and diamond yields results which agree well with experiment. The physical origin of the negative thermal expansion observed in silicon is explained. A tight-binding total energy model is generated capable of describing carbon systems with a variety of atomic coordinations and topologies. The model reproduces the total energy versus volume curves of various carbon polytypes as well as phonons and elastic constants of diamond and graphite. The model has also been used in the molecular-dynamics simulation of the properties of carbon clusters. The calculated ground-state geometries of small clusters (C{sub 2}--C{sub 10}) correlates well with results from accurate quantum chemical calculations, and the structural trend of clusters from C{sub 2} to C{sub 60} are investigated. 67 refs., 19 figs.
Date:
October 25, 1991
Creator:
Xu, Chunhui.
Object Type:
Report
System:
The UNT Digital Library
Thin polymer icemaker development and test program
We have constructed and tested a small device to produce ice in ice/water mixtures using a cold fluid as the heat sink. The device is a flexible heat exchanger constructed from a thin film of a suitable polymer. When filled with circulating liquid coolant the heat exchanger consists of an inflated series of parallel tubes; ice forms on the outside in complementary half cylinders. When the circulation is cut off, gravity drains the coolant and the static head of the water bath crushes the tubes, freeing them from the ice which floats to the surface. Brine circulation is then re-started and the cycle begins again. Here we report recent testing of this device: it makes ice readily under water and easily sheds the semi-cylinders of ice over many cycles of operation. It produces ice at a rate of 10 kg/m{sup 2}-hour. It offers substantial benefits in simplicity and reliability over mechanical harvester ice making systems, and the potential for significant improvements in energy efficiency compared to systems which use a re-heat cycle to harvest the ice. A reliable method of leak detection has been developed. The device should be of substantial value to systems where efficiency and reliability are at …
Date:
August 1, 1991
Creator:
Leigh, R.W. (Pratt Inst., Brooklyn, NY (United States))
Object Type:
Report
System:
The UNT Digital Library
Least cost planning from a customer's perspective
In this paper, I offer some thoughts about least cost planning, not from the perspective of the regulator or utility, but from the perspective of a residential customer. The problem that I address is, as a homeowner in northern Virginia, I am about to make a long term fuel choice for my household, where the options include, natural gas, electricity and fuel oil. An additional choice is the energy efficiency capital investment in my home that could decrease my monthly fuel costs. My decision process, hopefully as a rational consumer, offers implications about the efficiency of various services provided by all three fuel suppliers, including the local natural gas distribution companies (LDC).
Date:
March 2, 1992
Creator:
Sutherland, R.J.
Object Type:
Article
System:
The UNT Digital Library
Environmental recordkeeping: The administrative record
This document provides information on an environmental records management system. It includes information on environmental recordkeeping; environmental regulations with emphasis on the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); and the administrative record including a case study of the Hanford Site's administrative record system. This paper will focus on the following objectives: (1) Identify resources that can be used as reference tools; (2) understand the reasons for developing and maintaining an administrative record; and, (3) evaluate an existing system and identify means of complying with the regulations. 15 refs., 2 figs.
Date:
August 1, 1991
Creator:
Sprouse, B.S.
Object Type:
Article
System:
The UNT Digital Library
The rate dependence of the saturation flow stress of Cu and 1100 Al
The strain-rate dependence of the saturation flow stress of OFHC Cu and 1100 Al from 10{sup {minus}3}s{sup {minus}1} to nearly to 10{sup 12}s{sup {minus}1} is examined. The flow stress above 10{sup 9}s{sup {minus}1} is estimated using Wallace's theory of overdriven shocks in metals. A transition to the power-law behavior {Psi} {approximately} {tau}{sub s}{sup 5} occurs at a strain rate of order 10{sup 5}s{sup {minus}1}. 10 refs., 2 figs.
Date:
January 1, 1991
Creator:
Preston, D.L.; Tonks, D.L. & Wallace, D.C.
Object Type:
Article
System:
The UNT Digital Library
Hot gas desulfurization with oxides of zinc, iron, and vanadium
The objective of this study is to develop an improved sorbent which can reduce H{sub 2}S levels up to 1 ppmv or less, which can stabilize zinc, and produce economically recoverable amounts of elemental sulfur during regeneration. For this purpose, the desulfurization performance of sorbents prepared by the addition of various amounts of V{sub 2}O{sub 5} to the zinc ferrite sorbent is investigated.
Date:
January 1, 1992
Creator:
Akyurtlu, J.F. & Akyurtlu, A.
Object Type:
Article
System:
The UNT Digital Library
Jet rates from deep inelastic muon scattering in the W range of 15 to 35 GeV
Production rates of forward jets in deep inelastic muon scattering are studied using the JADE jet finding algorithm. The evolution of di-jet rates with W is compared to QCD first order predictions in the W range of 15 to 25 GeV. 7 refs., 3 figs.
Date:
August 1, 1991
Creator:
Salgado, C.
Object Type:
Article
System:
The UNT Digital Library
Lattice gaugefixing and other optics in lattice gauge theory
We present results from four projects. In the first, quark and gluon propagators and effective masses and {Delta}I = 1/2 Rule operator matching coefficients are computed numerically in gaugefixed lattice QCD. In the second, the same quantities are evaluated analytically in the strong coupling, N {yields} {infinity} limit. In the third project, the Schwinger model is studied in covariant gauges, where we show that the effective electron mass varies with the gauge parameter and that longitudinal gaugefixing ambiguities affect operator product expansion coefficients (analogous to {Delta}I = 1/2 Rule matching coefficients) determined by matching gauge variant matrix elements. However, we find that matching coefficients even if shifted by the unphysical modes are {xi} invariant. In the fourth project, we show that the strong coupling parallelogram lattice Schwinger model as a different thermodynamic limit than the weak coupling continuum limit. As a function of lattice skewness angle these models span the {Delta} = {minus}1 critical line of 6-vertex models which, in turn, have been identified as c = 1 conformal field theories.
Date:
June 1, 1992
Creator:
Yee, Ken.
Object Type:
Report
System:
The UNT Digital Library
Micro-scale mass-transfer variations during electrodeposition
Results of two studies on micro-scale mass-transfer enhancement are reported: (1) Profiled cross-sections of striated zinc surfaces deposited in laminar channel flow were analyzed with fast-fourier transforms (FFT) to determine preferred striation wavelengths. Striation frequency increases with current density until a minimum separation between striae of 150 {mu}m is reached. Beyond this point, independent of substrate used, striae meld together and form a relatively smooth, nodular deposit. Substrates equipped with artificial micron-sized protrusions result in significantly different macro-morphology in zinc deposits. Micro-patterned electrodes (MPE) with hemispherical protrusions 5 {mu}m in diameter yield thin zinc striae at current densities that ordinarily produce random nodular deposits. MPEs with artificial hemi-cylinders, 2.5 {mu}m in height and spaced 250 {mu}m apart, form striae with a period which matches the spacing of micron-sized ridges. (2) A novel, corrosion-resistant micromosaic electrode was fabricated on a silicon wafer. Measurements of mass-transport enhancement to a vertical micromosaic electrode caused by parallel bubble streams rising inside of the diffusion boundary-layer demonstrated the presence of two co-temporal enhancement mechanisms: surface-renewal increases the limiting current within five bubble diameters of the rising column, while bubble-induced laminar flows cause weaker enhancement over a much broader swath. The enhancement caused by bubble curtains …
Date:
August 1, 1991
Creator:
Sutija, D.P.
Object Type:
Report
System:
The UNT Digital Library
Investigation of breached depleted UF sub 6 cylinders
In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. An investigation team was immediately formed to determine the cause of the failures and their impact on future storage procedures and to recommend corrective actions. Subsequent investigation showed that the failures most probably resulted from mechanical damage that occurred at the time that the cylinders had been placed in the storage yard. In both cylinders evidence pointed to the impact of a lifting lug of an adjacent cylinder near the front stiffening ring, where deflection of cylinder could occur only by tearing the cylinder. The impacts appear to have punctured the cylinders and thereby set up corrosion processes that greatly extended the openings in the wall and obliterated the original crack. Fortunately, the reaction products formed by this process were relatively protective and prevented any large-scale loss of uranium. The main factors that precipitated the failures were inadequate spacing between cylinders and deviations in the orientations of lifting lugs from their intended horizontal position. After reviewing the causes and effects of the failures, the …
Date:
January 1, 1991
Creator:
DeVan, J. H.
Object Type:
Article
System:
The UNT Digital Library
Precision measurement of the direct CP violation parameter. var epsilon. prime /. var epsilon. via the four K yields 2. pi. decay modes and a high sensitivity search for CP violating rare K sub L decays, Task J
This report discusses the progress on the measurement of the direct CP violation parameter {var epsilon}{prime}/{var epsilon} and the rare KL decay. The progress has been as follows: (A) results from the complete E731 data set which was collected in the 1987/88 fixed target run; preparations for and the taking of the data for (B) E773 (CPT symmetry test) and (C) E799 (rare decay study); and finally (D) R D for a new detector to further study {var epsilon}{prime}/{var epsilon} and rate decays.
Date:
April 1, 1992
Creator:
Wah, Yau W.
Object Type:
Report
System:
The UNT Digital Library