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Fundamental studies of catalytic processing of synthetic liquids (open access)

Fundamental studies of catalytic processing of synthetic liquids

This project revolves around understanding the fundamental processes involved in the catalytic removal of harmful oxygenated organics present in coal liquids. We will model the complex type of sulfided Mo catalyst proposed for these reactions with a simple single crystal surfaces that display a controlled range and number of reaction sites and can be extensively characterized by surface science techniques.
Date: April 10, 1990
Creator: Watson, P. R.
System: The UNT Digital Library
Dynamics and pattern selection at the crystal-melt interface (open access)

Dynamics and pattern selection at the crystal-melt interface

This paper discusses dendritic sidebranching; anisotropic surface tension; light scattering at the crystal-melt interface; and succinonitrite-dye mixtures.
Date: December 10, 1990
Creator: Cummins, H. Z.
System: The UNT Digital Library
Mechanistic studies on reactivities of organometallic macrocyclic complexes of chromium and cobalt (open access)

Mechanistic studies on reactivities of organometallic macrocyclic complexes of chromium and cobalt

Reaction pathways leading to the formation and cleavage of a transition metal-carbon bond at various oxidation states of the metal occupy a central position in understanding many enzymatic reactions and designing catalysts. The report is divided into six parts that (1) focus on the homolysis vs heterolysis of a C-Cr(III) bond, (2) describes a unique chain reaction and a S{sub E}2 reaction I{sub 2} and RCrL{sup 2+}, (3) concerns the oxidation of organochromium(III) complexes by dihalide and pseudo-dihalide radical anions generated by pulse radiolysis, (4) concentrates on the oxidation mechanism of RCr(H{sub 2}O){sup 2+} and the fate of RCr(H{sub 2}O){sup 3+} as well as the corresponding reduction potentials, (5) extends study of organocobalt complexes with attention to reduction induced cleavages of a transition metal-carbon bond, and (6) describes the crystallization of ((CH{sub 3}){sub 4}N)(Co(dmgBF{sub 2}){sub 2}py) and reports its molecular structure as determined by x-ray diffraction. 182 refs., 25 figs., 16 tabs. (BM)
Date: December 10, 1990
Creator: Shi, Shu.
System: The UNT Digital Library
Radiation studies in the antiproton source (open access)

Radiation studies in the antiproton source

Experiment E760 has a lead glass (Pb-G) calorimeter situated in the antiproton source tunnel in the accumulator ring at location A50. This location is exposed to radiation from several sources during antiproton stacking operations. A series of radiation studies has been performed over the last two years to determine the sources of this radiation and as a result, some shielding has been installed in the antiproton source in order to protect the lead glass from radiation damage.
Date: September 10, 1990
Creator: Church, M.
System: The UNT Digital Library
(Studies of non-linear dynamics of dissipative systems) (open access)

(Studies of non-linear dynamics of dissipative systems)

In the period of this grant I worked on three main areas: (1) Symmetries in inviscid flow equations in one, two, and three dimensions and related nonlinear stability theorems for these flows; (2) applications of Hamiltonian mechanics to the problems of shallow water equations and internal wave dynamics in oceanic flows; and, (3) analysis of signals from chaotic systems with an eye toward learning how to build models of chaotic systems in nature.
Date: September 10, 1990
Creator: Abarbanel, D.I.
System: The UNT Digital Library
Secure resource management: Specifying and testing secure operating systems (open access)

Secure resource management: Specifying and testing secure operating systems

Much work has been devoted to methods for reasoning about the specifications of operating system specifications, the goal being to develop specifications for an operating system that are verified to be secure. Before the verification should be attempted, the specifications should be tested. This paper presents tools that can assist in the security testing of specifications. The first tool is based on the final Algebra Specification and Execution (FASE) system, and would be used to test specifications with real input values. FASE is an executable specification language which is operational in style, in which entities are represented in terms of their observable behavior. To facilitate the testing of an operating system (and its specification), use FASE we have specified a Secure Resource Manager (SRM), a generic template of an operating system. The SRM specification can be specialized to a specification of a particular operating system; the SRM is quite general and handles most features of modern nondistributed operating systems. The second tool, called the PLANNER, is used to derive a sequence of operations that exhibits a security flaw, most often a covert channel for information flow. The PLANNER is based on classical methods of AI planning, specialized to achieve goals …
Date: April 10, 1990
Creator: Archer, M.; Frincke, D.A. & Levitt, K. (California Univ., Davis, CA (USA). Div. of Computer Science)
System: The UNT Digital Library
A novel process for manufacture of methanol (open access)

A novel process for manufacture of methanol

To determine the effect of alternate catalysts on the synthesis. This will include copper chromite catalysts impregnated with alkali metals such as potassium, rubidium and cesium as well as their use as homogenous catalysts in the form of methoxides or similar salts. The use of various copper chromite catalysts with different compositions will be studied: e.g. substituting barium for manganses in copper chromite catalyst has a beneficial effect. To determine the nature of the active catalysts in this reaction and the effect of deactivating agents such as CO{sub 2}, H{sub 2}O and CO. To determine the rate limiting steps in this reaction so that proper scale-up is possible. The effects of catalysts loading and reactor volume are of special importance. To develop mathematical models which can be used for prediction of rates of reaction and are suitable for scale-up of the reaction.
Date: January 10, 1990
Creator: Tierney, J.W. & Wender, I.
System: The UNT Digital Library
Indirect fluorometric detection techniques on thin layer chromatography and effect of ultrasound on gel electrophoresis (open access)

Indirect fluorometric detection techniques on thin layer chromatography and effect of ultrasound on gel electrophoresis

Thin-layer chromatography (TLC) is a broadly applicable separation technique. It offers many advantages over high performance liquid chromatography (HPLC), such as easily adapted for two-dimensional separation, for whole-column'' detection and for handling multiple samples, etc. However, due to its draggy development of detection techniques comparing with HPLC, TLC has not received the attention it deserves. Therefore, exploring new detection techniques is very important to the development of TLC. It is the principal of this dissertation to present a new detection method for TLC -- indirect fluorometric detection method. This detection technique is universal sensitive, nondestructive, and simple. This will be described in detail from Sections 1 through Section 5. Section 1 and 3 describe the indirect fluorometric detection of anions and nonelectrolytes in TLC. In Section 2, a detection method for cations based on fluorescence quenching of ethidium bromide is presented. In Section 4, a simple and interesting TLC experiment is designed, three different fluorescence detection principles are used for the determination of caffeine, saccharin and sodium benzoate in beverages. A laser-based indirect fluorometric detection technique in TLC is developed in Section 5. Section 6 is totally different from Sections 1 through 5. An ultrasonic effect on the separation of …
Date: December 10, 1990
Creator: Yinfa, Ma.
System: The UNT Digital Library
DYNA3D example problem manual (open access)

DYNA3D example problem manual

This manual describes in detail the solution of ten example problems using the explicit nonlinear finite element code DYNA3D. The sample problems include solid, shell, and beam element types, and a variety of linear and nonlinear material models. For each example, there is first an engineering description of the physical problem to be studied. Next, the analytical techniques incorporated in the model are discussed and key features of DYNA3D are highlighted. INGRID commands used to generate the mesh are listed, and sample plots from the DYNA3D analysis are given. Finally, there is a description of the TAURUS post-processing commands used to generate the plots of the solution. This set of example problems is useful in verifying the installation of DYNA3D on a new computer system. In addition, these documented analyses illustrate the application of DYNA3D to a variety of engineering problems, and thus this manual should be helpful to new analysts getting started with DYNA3D. 7 refs., 56 figs., 9 tabs.
Date: October 10, 1990
Creator: Lovejoy, S.C. & Whirley, R.G.
System: The UNT Digital Library
The effects of tributyl phosphate on a polymeric ultrafilter (open access)

The effects of tributyl phosphate on a polymeric ultrafilter

The purpose of this project was to determine the effects that tributyl phosphate (TBP) would have on a polysulfone crossflow ultrafilter. Aqueous simulant solutions containing TBP (100 or 1000 mg/L) and Fe(III), Si(IV), Al(III), and NaNO{sub 3} were examined. Results obtained from simulant solutions containing 100 mg/L TBP were virtually identical to those obtained in the absence of TBP. However, a solution containing higher concentrations of TBP (1000 mg/L) very rapidly reduced the permeate flow rate to nearly zero. Chemical cleaning was successful in restoring initial flow rates. Permeate flux was plotted as a function of transmembrane pressure for clean water before and after the filter had been exposed to TBP. Also, the axial pressure drop was plotted as a function of the Reynolds numbers. Linear correlation of these data suggested that the filter did not swell or become distorted. Therefore, it was concluded that TBP does not have a permanent effect on this polysulfone ultrafilter. 6 refs., 7 figs., 1 tab.
Date: August 10, 1990
Creator: Stewart, C.A.
System: The UNT Digital Library
Report of Foreign Travel of F. Plasil. August 1990 (open access)

Report of Foreign Travel of F. Plasil. August 1990

The traveler spent eleven intense days at CERN, Switzerland. His time was divided between daytime, when he worked mainly on L* issues, and evenings/nights, when he performed shift work during the current run of the WA80 collaboration. It was decided to reduce the size and cost of the proposed L* experiment. Strategy for SSC subsystem proposals was discussed, and several relevant decisions were made.
Date: September 10, 1990
Creator: Plasil, F.
System: The UNT Digital Library
The CSMS (Configurable Seismic Monitoring System) Poorboy deployment: Seismic recording in Pinedale, Wyoming, of the Bullion NTS (Nevada Test Site) nuclear test under the verification provisions of the new TTBT protocol (open access)

The CSMS (Configurable Seismic Monitoring System) Poorboy deployment: Seismic recording in Pinedale, Wyoming, of the Bullion NTS (Nevada Test Site) nuclear test under the verification provisions of the new TTBT protocol

The Configurable Seismic Monitoring System (CSMS), developed at the Lawrence Livermore National Laboratory (LLNL) was deployed in a 13-m deep vault on the AFTAC facility at Pinedale, Wyoming to record the Bullion nuclear test. The purpose of the exercise was to meet all provisions of the new TTBT protocol on in-country seismic recording at a Designated Seismic Station (DSS). The CSMS successfully recorded the Bullion event consistent with and meeting all requirements in the new treaty protocol. In addition, desirable seismic system features not specified in the treaty protocol were determined; treaty protocol ambiguities were identified, and useful background noise recordings at the Pinedale site were obtained. 10 figs.
Date: July 10, 1990
Creator: Harben, P. E.; Rock, D. W. & Carlson, R. C.
System: The UNT Digital Library
Pacific Missile Test Center Information Resources Management Organization (code 0300): The ORACLE client-server and distributed processing architecture (open access)

Pacific Missile Test Center Information Resources Management Organization (code 0300): The ORACLE client-server and distributed processing architecture

Computing architectures using distributed processing and distributed databases are increasingly becoming considered acceptable solutions for advanced data processing systems. This is occurring even though there is still considerable professional debate as to what truly'' distributed computing actually is and despite the relative lack of advanced relational database management software (RDBMS) capable of meeting database and system integrity requirements for developing reliable integrated systems. This study investigates the functionally of ORACLE data base management software that is performing distributed processing between a MicroVAX/VMS minicomputer and three MS-DOS-based microcomputers. The ORACLE database resides on the MicroVAX and is accessed from the microcomputers with ORACLE SQL*NET, DECnet, and ORACLE PC TOOL PACKS. Data gathered during the study reveals that there is a demonstrable decrease in CPU demand on the MicroVAX, due to distributed processing'', when the ORACLE PC Tools are used to access the database as opposed to database access from dumb'' terminals. Also discovered were several hardware/software constraints that must be considered in implementing various software modules. The results of the study indicate that this distributed data processing architecture is becoming sufficiently mature, reliable, and should be considered for developing applications that reduce processing on central hosts. 33 refs., 2 figs.
Date: June 10, 1990
Creator: Beckwith, A. L. & Phillips, J. T.
System: The UNT Digital Library
Report of Foreign Travel of J. D. White, Program Manager, September 1990 (open access)

Report of Foreign Travel of J. D. White, Program Manager, September 1990

While on vacation, the traveler attended the European Nuclear Conference in Lyon, France. This trip was part of an outside activity approved by DOE. The traveler is a consultant to Loyola College, serving as chairman of a panel to assess the state of the art in the controls and instrumentation technology in the European nuclear community. This study is being conducted by Loyola College under subcontract to the National Science Foundation. The traveler was surprised by the level of automation claimed (by the company Siemens AG KWU) to be present in the German Konvoi nuclear power plants. The claim was that this was done to improve the safety of the plant by keeping the operator out of the loop'' for the first 30 minutes of some transients or accidents.
Date: October 10, 1990
Creator: White, J. D.
System: The UNT Digital Library
The effect of slightly faster strain rates and internal hydrogen on uranium-0. 8 weight percent titanium alloy mechanical properties (open access)

The effect of slightly faster strain rates and internal hydrogen on uranium-0. 8 weight percent titanium alloy mechanical properties

Mechanical testing of uranium-0.8 wt % titanium (U-0.8 wt % Ti) alloys can affect the outcome of mechanical properties, primarily ductility, by varying the crosshead velocity, which changes the strain rate. However, most specifications that govern mechanical properties of this alloy reference ASTM E-8, which limits the speed to 0.5 in./in. of gage length per minute. Our current procedure for testing U-0.8 Ti is not at the maximum speed permitted in ASTM E-8, so an experiment was designed to evaluate the effect of maximizing the crosshead velocity per ASTM E-8. In order to create a fair assessment, tensile specimens were prepared that were low in internal hydrogen (0.02 ppM) and higher in internal hydrogen (0.36 ppM). External hydrogen effects were minimized by testing in a controlled environment that contained less than 10% relative humidity. Test results showed that for the low hydrogen test group, increasing the crosshead velocity caused a significant increase in reduction in area (RA), but not in elongation. For the higher hydrogen test group, increasing the speed resulted in a significant increase in RA and an increase, though not statistically significant, in elongation. Of equal importance was an observation that strongly suggests a correlation between material defects, …
Date: October 10, 1990
Creator: Bird, E. L.
System: The UNT Digital Library
Electromagnetic interactions with nuclei and nucleons (open access)

Electromagnetic interactions with nuclei and nucleons

This report discusses the following topics: general LEGS work; photodisintegration of the deuteron; progress towards other experiments; LEGS instrumentation; major LEGS software projects; NaI detector system; nucleon detector system; waveshifting fibers; EGN prototype detector for CEBAF; photon beam facility at CEBAF; delta electroproduction in nuclei; quasielastic scattering and excitation of the Delta by {sup 4}He(e,e{prime}); and quasielastic scattering at high Q{sup 2}.
Date: November 10, 1990
Creator: Thornton, Stephen T. & Sealock, Richard M.
System: The UNT Digital Library
Study of Drift Tube Resolution Using Numerical Simulations (open access)

Study of Drift Tube Resolution Using Numerical Simulations

The results off a simulation of straw tube detector response are presented. These gas ionization detectors and the electronics which must presumably go along with them are characterized in a simple but meaningful manner. The physical processes which comprise the response of the individual straw tubes are broken down and examined in detail. Different parameters of the simulation are varied and resulting predictions of drift tube spatial resolution are shown. In addition, small aspects of the predictions are compared to recent laboratory results, which can be seen as a measure of the simulation's usefulness. 10 refs., 8 figs.
Date: October 10, 1990
Creator: Lundin, Mark C.
System: The UNT Digital Library
Roles of additives and surface control in slurry atomization (open access)

Roles of additives and surface control in slurry atomization

Airblast atomization of micronized coal water slurry is carried out using twin-fluid jet atomizers of various distributor designs. Drop size and size distribution are measured using the laser diffraction technique. We found that the atomized drop sizes of micronized coal water slurries substantially decrease as the atomizing air pressure exceeds a threshold value. We also found that the atomized drop size, represented by the mass median diameter (MMD) can be described by the wave mechanism-based models in terms of three non-dimensional groups, namely, slurry-to-air mass ratio, the Weber number, and the Ohnesorge number. 11 refs.
Date: July 10, 1990
Creator: Tsai, S.C.
System: The UNT Digital Library
Milliwatt Generator Heat Source Progress Report, January--December 1989 (open access)

Milliwatt Generator Heat Source Progress Report, January--December 1989

All hardware shipments to LANL were made on or ahead of schedule, thus satisfying all War Reserve and other hardware/yttrium requirements for the reporting period January--December 1989. A special investigation was conducted to determine the source of a surface staining'' problem observed on some T-111 components. Although the cause was not positively identified, the actions taken as a result of the investigation dramatically reduced both the frequency of occurrence and the magnitude of the problem. Hardware fabrication activates continued in an efficient and timely manner, with production losses at a minimal level. During the reporting period, a 99.4% utilization yield was realized, with a 0.8 dollar percent defectiveness. 1 ref., 15 figs., 5 tabs.
Date: September 10, 1990
Creator: Saylor, Ranny W.
System: The UNT Digital Library
Fundamental studies of catalytic processing of synthetic liquids. Quarterly progress report, January 1, 1990--March 31, 1990 (open access)

Fundamental studies of catalytic processing of synthetic liquids. Quarterly progress report, January 1, 1990--March 31, 1990

This project revolves around understanding the fundamental processes involved in the catalytic removal of harmful oxygenated organics present in coal liquids. We will model the complex type of sulfided Mo catalyst proposed for these reactions with a simple single crystal surfaces that display a controlled range and number of reaction sites and can be extensively characterized by surface science techniques.
Date: April 10, 1990
Creator: Watson, P. R.
System: The UNT Digital Library
D-Zero Central Calorimeter Inner Vessel Pumpdown Information (open access)

D-Zero Central Calorimeter Inner Vessel Pumpdown Information

The information presented in this engineering note can be of value to others who wish to predict pumping times and water content of vessels containing G-IO material. Four predictions of the water content of the G-IO in the D-Zero Central Calorimeter (CC) are given. Experience from pumping on the NW A cryostat was used to help predict the pumpdown time required for the CC. The actual pumpdown time and water removal from the CC agrees quite well with those predicted which gives confidence for future predictions done using the information presented in this engineering note. A listing of the predictions and actual CC pumpdown particulars is given.
Date: December 10, 1990
Creator: Rucinski, R.
System: The UNT Digital Library
Linac BPM (Beam Position Monitor) modification program status (open access)

Linac BPM (Beam Position Monitor) modification program status

In the fall of 1988 the Beam Position Monitor (BPM) Task Force recommended that linac BPM processors be pulled out of the linac, modified, adjusted for offsets, recalibrated, and reinstalled. As of the end of 1989 this process had been completed on all linac type BPM processors. This paper discusses these modifications and tests.
Date: February 10, 1990
Creator: Smith, S. & Williams, S.
System: The UNT Digital Library
Molten-caustic-leaching (Gravimelt) system integration project. Quarterly report, October--December 1989 (open access)

Molten-caustic-leaching (Gravimelt) system integration project. Quarterly report, October--December 1989

Operation of the Gravimelt Integrated Test Circuit for desulfurization and demineralization of coal was completed in a previous quarter when a 48-test process matrix was performed over 750 hours of operational time resulting in the production of 3,000 pounds of treated coal suitable for further test and evaluation. Analysis of the large quantity of data collected continued during the current quarter. Assessment of trace elements in the feed and product coal for two runs (one with Pittsburgh No. 8 coal and one with Kentucky No. 9 coal) indicates that greater than 96% of the silicon, iron and aluminium was removed for both coals. A trace element analysis for 21 elements is presented in the quarterly. Selected samples of the product coal were placed in a GN{sub 2}-purged oven for six hours at 140{degree}F to remove about 15% of the moisture from the samples. These samples were repackaged in 55-gallon drums and shipped to DoE. Data from shakedown was analyzed in detail with particular attention paid to coal product quality (sulfur and ash), carbonate and humic acid formation, particle size distribution, liquid sample analysis, and wash train performance.
Date: January 10, 1990
Creator: unknown
System: The UNT Digital Library
Chemical and nuclear properties of lawrencium (element 103) and hahnium (element 105) (open access)

Chemical and nuclear properties of lawrencium (element 103) and hahnium (element 105)

The chemical and nuclear properties of Lr and Ha have been studied, using 3-minute {sup 260}Lr and 35-second {sup 262}Ha. The crystal ionic radius of Lr{sup 3+} was determined by comparing its elution position from a cation-exchange resin column with those of lanthanide elements having known ionic radii. Comparisons are made to the ionic radii of the heavy actinides, Am{sup 3+} through Es{sup 3+}, obtained by x-ray diffraction methods, and to Md{sup 3+} and Fm{sup 3+} which were determined in the same manner as Lr{sup 3+}. The hydration enthalpy of {minus}3622 kJ/mol was calculated from the crystal ionic radius using an empirical form of the Born equation. Comparisons to the spacings between the ionic radii of the heaviest members of the lanthanide series show that the 2Z spacing between Lr{sup 3+} and Md{sup 3+} is anomalously small, as the ionic radius of Lr{sup 3+} of 0.0886 nm is significantly smaller than had been expected. The chemical properties of Ha were determined relative to the lighter homologs in group 5, Nb and Ta. Group 4 and group 5 tracer activities, as well as Ha, were absorbed onto glass surfaces as a first step toward the determination of the chemical properties of …
Date: September 10, 1990
Creator: Henderson, Roger Alan
System: The UNT Digital Library