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UCLA program in reactor studies: The ARIES tokamak reactor study

Description: The ARIES research program is a multi-institutional effort to develop several visions of tokamak reactors with enhanced economic, safety, and environmental features. The aims are to determine the potential economics, safety, and environmental features of a range of possible tokamak reactors, and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Four ARIES visions are currently planned for the ARIES program. The ARIES-1 design is a DT-burning reactor based on modest'' extrapolations from the present tokamak physics database and relies on either existing technology or technology for which trends are already in place, often in programs outside fusion. ARIES-2 and ARIES-4 are DT-burning reactors which will employ potential advances in physics. The ARIES-2 and ARIES-4 designs employ the same plasma core but have two distinct fusion power core designs; ARIES-2 utilize the lithium as the coolant and breeder and vanadium alloys as the structural material while ARIES-4 utilizes helium is the coolant, solid tritium breeders, and SiC composite as the structural material. Lastly, the ARIES-3 is a conceptual D-{sup 3}He reactor. During the period Dec. 1, 1990 to Nov. 31, 1991, most of the ARIES activity has been directed toward completing the technical work for the ARIES-3 design and documenting the results and findings. We have also completed the documentation for the ARIES-1 design and presented the results in various meetings and conferences. During the last quarter, we have initiated the scoping phase for ARIES-2 and ARIES-4 designs.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department

(Energy related studies utilizing microline thermochronology)

Description: The past two years of research conducted have been fruitful and exciting. Using Microcline Thermochronology (MTC), we have investigated the hydrothermal maturity of the Salton Sea Geothermal Field, potential for hydrocarbon maturation associated with heating due to ridge subduction beneath accretionary prism sediments, developed a single crystal dating system which has proven to greatly enhance interpretations regarding MTC, and also have begun to develop sound theoretical and experimental techniques which truly revolutionize our understanding of argon systematics in K-feldspars.
Date: January 1, 1989
Partner: UNT Libraries Government Documents Department

(Energy related studies utilizing microline thermochronology)

Description: In our first year of the current funding cycle, we have investigated three interrelated aspects of K-feldspar thermochronology; (1) the Ar diffusion properties and microstructures of K-feldspars, (2) the thermal evolution of the Valles Caldera and (3) the continued development of microanalysis. Results of TEM and light microscopy on heated and unheated samples of MH-10 K-feldspar reveal three classes of substructure are present: (1) cross hatched extinction is common and there is almost no albite/pericline twinning, only tweed microstructure; (2) 5--10 vol. % of this K-feldspar are turbid zones with complex twin and tweed structures at the sub-micron scale and numerous dislocation and strain features; (3) about 20% of the K-feldspar is comprised of 0.01 {times} 0.2-1{mu}m albite exsolution lamellae. The network of fractured/turbid zones divides the sample into blocks of approximately 50 {mu}m and the separation between albite exsolution lamellae produce K-feldspar domains of the order 0.1 {mu}m. Independent crushing and diffusion experiments suggest the scale of the largest domain is order ten's of micron whereas the smallest domain size is inferred to be {approximately}0.1 {mu}m. Many, and perhaps most, alkali feldspars contain diffusion domains with activation energies that may vary by as much as 8 kcal/mol. An extraordinary consequence of even relatively small variations in activation energy between domains is that the shape of an age spectrum can change dramatically by varying the laboratory heating schedule. We have performed {sup 40}Ar/{sup 39}Ar age spectrum experiments on K-feldspar separated from Proterozoic quartz monzonite taken from a depth of 1.76 km down the VC-2B drill hole, Valles Caldera, north-central New Mexcio.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department

(Energy related studies utilizing K-feldspar thermochronology)

Description: In our second year of current funding cycle, we have investigated the Ar diffusion properties and microstructures of K-feldspars and the application of domain theory to natural K-feldspars. We completed a combined TEM and argon diffusion study of the effect of laboratory heat treatment on the microstructure and kinetic properties of K-feldspar. We conclude in companion papers that, with one minor exception, no observable change in the diffusion behavior occurs during laboratory extraction procedures until significant fusion occurs at about 1100{degrees}C. The effect that is observed involves a correlation between the homogenization of cryptoperthite lamelle and the apparent increase in retentivity of about 5% of the argon in the K-feldspar under study. We can explain this effect of both as an artifact of the experiment or the loss of a diffusion boundary. Experiments are being considered to resolve this question. Refinements have been made to our experimental protocol that appears that greatly enhance the retrieval of multi-activation energies from K-feldspars. We have applied the multi-domain model to a variety of natural environments (Valles Caldera, Red River fault, Appalachian basin) with some surprising results. Detailed {sup 40}Ar/{sup 39} Ar coverage of the Red River shear zone, thought to be responsible for the accommodation of a significant fraction of the Indo-Asian convergence, strongly suggests that our technique can precisely date both the termination of ductile strike-slip motion and the initiation of normal faulting. Work has continued on improving our numerical codes for calculating thermal histories and the development of computer based graphing tools has significantly increased our productivity.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department

Particle physics

Description: This report discusses: rare and forbidden decays of eta mesons and muons to test the standard model; tests of charge symmetry and isospin invariance; studies of baryon resonances; and exploratory investigations in support of the new programs under consideration. (LSP)
Date: October 1, 1991
Creator: Nefkens, B.M.K.
Partner: UNT Libraries Government Documents Department

High resolution Raman spectroscopy of complexes and clusters in molecular beams

Description: The DOE-sponsored project in this laboratory has two facets. The first is the development of methods of nonlinear Raman spectroscopy for application in studies of sparse samples. The second is the application of such methods to structural and dynamical studies of species in supersonic molecular beams. The progress we have made in both of these areas is described in this paper. The report is divided into five remaining sections. The first pertains to theoretical and experimental developments in Fourier transform stimulated emission spectroscopy and Fourier transform hole-burning spectroscopy. The second deals with progress in the development of ionization-detected stimulated Raman spectroscopies (IDSRS). The third describes results from the application of IDSRS methods to studies of jet-cooled benzene clusters. The fourth describes IDSRS results from studies of hydrogen-bonded complexes containing phenols. The fifth relates to studies of carbazole-(Ar){sub n} clusters.
Date: January 1, 1991
Creator: Felker, P.M.
Partner: UNT Libraries Government Documents Department

Cross flow induced vibrations in staggered arrays of cylindrical structures

Description: Flow induced vibrations cause by instability is the subject of this investigation. The bulk of the work performed is theoretical in nature, the comparison with some of existing experimental data is given for each of four models described. First model encompasses the effects of prescribed motion on the cylinder. Such circumstances occur in the case of vortex shedding initiated instability. The reduced velocity within the cylinder array is low and there is no coupling between the adjacent cylinders. Second model assumes certain form of vibration and corresponding behavior of the perturbed velocity field in temporal and one of spatial coordinates thus transforming partial differential equations into ordinary differential equations and takes into account the motion of the neighboring cylinder. This corresponds to fluid elastic controlled instabilities. The resulting equations are solved analytically. The model is used for better understanding of the equations of cylinder motion as well as for quick estimates of threshold of instability. Third model relaxes an assumption about the form of vibration in spatial direction and uses the vorticity formulation of equation of fluid motion to account for fluid-solid interaction. This model analysis is of two phase (air-water mixture) flow. The void fraction distribution is found to be the single most decisive factor to determine the onset of instability for such a domain. In conclusion, two distinct mechanism were found to be responsible for flow induced vibration caused instabilities, (1) outside source controlled periodic excitation (such as vortex shedding) -- described by the first model and (2) fluid elastic forces -- described by second, third and fourth models. For the values of reduced velocity below 0.7 first model is proposed, for the values above 0.7, the rest.
Date: December 31, 1991
Creator: Marn, J.
Partner: UNT Libraries Government Documents Department

An experimental investigation of two-phase crossflow over rigidly and flexibly mounted tubes

Description: Two-phase crossflow over heat exchanger tubes induces vibrations which contribute greatly to the wear on the tubes. Of the three mechanisms leading to two-phase flow-induced vibrations which have been identified, fluid-elastic instability has been recognized as that which leads to the vibrations with the largest amplitude. The mass damping parameter is used to predict the onset of fluid-elastic instability, and the mean drag coefficient is used to calculate the mass damping parameter. In this thesis, the drag coefficient measured over single tubes and tubes within array, in single-phase and two-phase flow at various Reynolds numbers, is discussed. The drag coefficient was measured by two methods. For flexibly mounted tubes, strain gages were mounted on cantilever beams which held the tube in place and allowed it to vibrate in the direction parallel to the flow only. For both rigidly and flexibly mounted tubes, pressure distributions were measured around the perimeter of the tube. Forces, and then the drag coefficient, could be calculated from this information. The drag coefficient was not found to depend upon the flexibility of the tube mounting. As the void fraction of the flow increases, the drag coefficient over the tube increases. This effect was found to be quite large at low Reynolds numbers, and weaker at higher Reynolds numbers, and a different effect was found at very high Reynolds numbers.
Date: December 31, 1991
Creator: Gerhart, S.M.
Partner: UNT Libraries Government Documents Department

Use of artificial intelligence in severe accident diagnosis for PWRs

Description: A combination approach of an expert system and neural networks is used to implement a prototype severe accident diagnostic system which would monitor the progression of the severe accident and provide necessary plant status information to assist the plant staff in accident management during the accident. The station blackout accident in a pressurized water reactor (PWR) is used as the study case. The current phase of research focus is on distinguishing different primary system failure modes and following the accident transient before and up to vessel breach.
Date: December 31, 1995
Creator: Wu, Zheng; Okrent, D. & Kastenberg, W.E.
Partner: UNT Libraries Government Documents Department

Fracture toughness of ordered intermetallic compounds exhibiting limited ductility and mechanical properties of ion-irradiated polycrystalline NiAl. Final report, July 1, 1986--June 30, 1997

Description: The focus of the research performed under the auspices of this grant changed several times during the lifetime of the project. The initial activity was an investigation of irradiation-induced amorphization of ordered intermetallic compounds, using energetic protons as the bombarding species. Two significant events stimulated a change of direction: (1) the proton accelerating facility that the authors had been using at the California State University at Los Angeles became unavailable late in 1988 because of a personnel matter involving the only individual capable of operating the machine; (2) they learned that disordering and amorphization of intermetallic compounds produced interesting effects on their mechanical properties. Loss of access t the local accelerator prompted a collaboration with Dr. Droa Pedraza of the Oak Ridge National Laboratory (ORNL), enabling access to the accelerator at ORNL. The influence of disordering and amorphization on mechanical properties ultimately stimulated the development of a miniaturized disk-bend testing (MDBT) facility, the intent of which was to provide semiquantitative and even quantitative measures of the mechanical behavior of ion-irradiated ordered intermetallic alloys. The second phase of the project involved the perfection and usage of the MDBT, and involved exploratory experiments on unirradiated materials like amorphous alloy ribbons and brittle grain boundaries in Ni{sub 3}Al. This report is a brief summary of the research highlights of the project, organized according to the activity that was emphasized at the time.
Date: September 1, 1997
Creator: Ardell, A.J.
Partner: UNT Libraries Government Documents Department

Impact of global climate change on ecosystem-level interactions among sympatric plants from all three photosynthetic pathways. Terminal report

Description: The proposed research will determine biochemical and physiological responses to variations in environmental factors for plants of all three photosynthetic pathways under competitive situations in the field. These responses will be used to predict the effects of global climatic change on an ecosystem in the northwestern Sonoran Desert where the C{sub 3} subshrub Encelia farinosa, the C{sub 4} bunchgrass Hilaria rigida, and the CAM succulent Agave deserti are co-dominants. These perennials are relatively short with overlapping shallow roots facilitating the experimental measurements as well as leading to competition for soil water. Net CO{sub 2} uptake over 24-h periods measured in the laboratory will be analyzed using an environmental productivity index (EPI) that can incorporate simultaneous effects of soil water, air temperature, and light. Based on EPI, net CO{sub 2} uptake and hence plant productivity will be predicted for the three species in the field under various treatments. Activity of the two CO{sub 2} fixation enzymes, Rubisco and PEPCase, will be determined for these various environmental conditions; also, partitioning of carbon to various organs will be measured based on {sup 14}CO{sub 2} labeling and dry weight analysis. Thus, enzymatic and partitioning controls on competition among sympatric model plants representing all three photosynthetic pathways will be investigated.
Date: December 17, 1997
Creator: Nobel, P.S.
Partner: UNT Libraries Government Documents Department

Use of Behaviorally Anchored Rating Scales (BARS) for deep technical knowledge

Description: The University of California at Los Angeles (UCLA) participated in a U.S. Nuclear Regulatory Commission research program to investigate methods to measure the effect of management and organization on nuclear plant safety. The UCLA research team focused its efforts on understanding {open_quotes}deep technical knowledge,{close_quotes} and its relation to probabilistic risk assessment. As a result, the research team combined deep technical knowledge with a commonly used rating system for understanding the effectiveness of management and organizations.
Date: December 31, 1993
Creator: Okrent, D.; Xions, Yongjie; Abbott, E.C. & Leonard, J.D. Jr.
Partner: UNT Libraries Government Documents Department

CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report

Description: The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net C0{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.
Date: December 31, 1994
Creator: Nobel, P.S.
Partner: UNT Libraries Government Documents Department

An experimental study of fluidelastic instability and draf force on a tube in two-phase cross flow

Description: Two-phase cross flow over heat exchanger tubes creates vibrations which contribute greatly to the wear on the tubes. Fluidelastic instability is a major mechanism by which tubes can fail. In this work, the fluidelastic instability of a tube placed in an array subjected to two-phase cross flow has been studied. For the determination of fluidelastic instability, a triangular tube array was used. The tubes were made of acrylic and were 2.2 cm or 2.37 cm in diameter and 20 cm in length. Eighteen tubes and 4 half tubes formed 5 rows with a pitch to diameter ratio of 1.4. All of the tubes except the test tube were rigidly supported at the text section wall. The test tube was flexibly supported with two cantilever beams. By installing cantilever beams horizontally and vertically, drag and lift direction tube vibration were studied. Parameters of tube mass, structural stiffness, natural frequency, and pitch to diameter ratio were varied. The drag coefficients on a rigidly held tube in an array subjected to two-phase cross flow were measured. The tube in an array was located at displaced positions as well as at the normal position in order to study the variation of fluid force as the tube vibrates. In the experiments, gap Reynolds numbers up to 1 x 10{sup 5} were obtained, while void fraction was varied from zero to 0.5. The drag coefficients in two-phase flow are much higher than those in single phase flow. The ratio of two-phase to single phase drag coefficient decreases as Reynolds number increases. The drag coefficient on a tube in an array increases as the tube is displaced in the direction of flow. The drag coefficient increases rapidly when the tube is displaced more than a certain critical distance.
Date: December 31, 1994
Creator: Joo, Youngcheol
Partner: UNT Libraries Government Documents Department

University of California, Los Angeles Campus School of Medicine Atomic Energy Project quarterly progress report for period ending March 31, 1952

Description: The fifteenth quarterly report being submitted for Contract No. AT04-1-GEN-12 is issued in accordance with Service Request Number 1 except for the report of the Alamogordo Section, Code 91810, which is submitted in accordance with the provisions of Service Request Number 2. Work is in progress on continuing existing projects. In addition, new projects have been initiated including the Kinetics and Mechanism of Protein Denaturation (10018); The Effect of Irradiation on the Constituents of Embryonic Serum (30033); and The Use of Controlled Atmospheres for Spectrographic Excitation Sources (40053). Many of the Project units are either wholly or partially completed and the following initial reports are available: Identification of Ferritin in Blood of Dogs Subjected to Radiation from an Atomic Detonation (UCLA-180); The Nutritional Value of Intravenous Tapioca Dextrin in Normal and Irradiated Rabbits (UCLA-181); The-Decarboxylation and Reconstitution of Linoleic Acid (UCLA-183); Preparation and Properties of Thymus Nucleic Acid (UCLA-184); The Radiation Chemistry of Cysteine Solutions Part II. (a) The Action of Sulfite on the Irradiated Solutions; (b) The Effect on Cystine (UCLA-185); A Revolving Specimen Stage for the Electron Microscope (UCLA-178); An Automatic Geiger-Mueller Tube Tester (UCLA-186); The Value of Gamma Radiation Dosimetry in Atomic Warfare Including a Discussion of Practical Dosage Ranges (UCLA-187); and A New Plastic Tape Film Badge Holder (UCLA-189). Two additional reports were issued; one by Dr. Wilbur Selle entitled Attempts to Alter the Response to Ionizing Radiations from the School of Medicine, UCLA (UCLA-176), and two, a restricted distribution report from the Alamogordo Section entitled Field Observations and Preliminary Field Data Obtained by the UCLA Survey Group on Operation Jangle, November 1951 (UCLA-182).
Date: April 10, 1952
Creator: Warren, S.L.
Partner: UNT Libraries Government Documents Department

The radioisotope osteogram: Kinetic studies of skeletal disorders in humans

Description: Radioactive strontium can serve as a tracer to gain information concerning calcium metabolism in human subjects. Gamma-emitting Sr{sup 85} is used rather than the much more hazardous, beta-emitting Sr{sup 89} and Sr{sup 90}. (ca{sup 47} -- the ideal tracer for normal calcium -- is quite expensive and difficult to procure.) Very significant information may be obtained merely by measuring and recording the changes in radioactivity in various body areas during the first hour after intravenous injection of the bone-seeking radioisotope. This is accomplished by placing a lead-shielded gamma-scintillation detector in contact with the skin over the sites of interest and recording the activities on a scaler or ratemeter. The activity versus time curves so obtained are called radioisotope osteograms. Data were presented which indicated that Sr{sup 85} osteograms for patients afflicted with osteoporosis, Paget`s disease, tumor metastases to bone, and possibly multiple myeloma, differ significantly from those obtained from subjects with no skeletal abnormalities. Some interpretations of these deviations were discussed. The value of conducting double-tracer tests (e.g. -- Sr{sup 85} plus radio-iodinated serum albumin) was demonstrated, and correlations with excretion data were made. With further refinements the technique may ultimately become useful for certain diagnostic problems in the clinic and.for evaluating the efficacy of treatment of these disorders.
Date: October 16, 1959
Creator: MacDonald, N.S.
Partner: UNT Libraries Government Documents Department

CO{sub 2} exchange, environmental productivity indices, and productivity of Agaves and Cacti under current and elevated atmospheric CO{sub 2} concentrations. Terminal report

Description: The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net CO{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.
Date: June 1, 1995
Partner: UNT Libraries Government Documents Department

Applications of mesoscopic physics

Description: This report discusses the following topics: Acoustical nondestructive evaluation of heterogeneous materials in the multiple scattering regime. Classical and quantum superdiffusion in a time-dependent random potential. Negative Magnetoresistance in Variable Range Hopping Conduction. Reproducible Conductance Fluctuations in Macroscopic Anderson Insulators. Feasibility of far-infared lasers using multiple semiconductor quantum wells.
Date: January 1, 1992
Creator: Feng, Shechao.
Partner: UNT Libraries Government Documents Department

Evaporation and burning of a spherical fuel droplet in a uniform convective flowfield

Description: An analytical/numerical model is developed for the evaporation and burning of a spherical fuel droplet in a subsonic crossflow. The external gaseous flowfield is represented using an approximate compressible potential-flow solution, while the internal flowfield of the droplet is represented by the classical Hill's spherical vortex. This allows a numerical solution for the external boundary layer, from which the droplet's effective drag coefficent, rate of mass loss, size, and the shape of the diffusion flame with infinitely fast chemical reaction kinetics are determined. Subsequently, the quasi-steady model with uniform liquid temperature is extended to examine the effects of the transient heating of the droplet interior. Time-dependent calculations are performed with updated droplet Reynolds numbers and updated surface temperatures. Comparisons of model predictions with experimental data are made. To examine the effects of finite-rate chemical reaction kinetics, a one-step formulation of the combustion mechanism is integrated into the gaseous boundary layer equations. Simplifying assumptions for the variation of gas properties commonly used in combustion calculations, are subjected to an examination as to their degree of accuracy. For this purpose, the droplet model is extended to account for the variation of gas properties with temperature and gas composition within the boundary layer. Comparisons are made between the predictions obtained from the different models developed in this study, as well as with existing experimental data.
Date: January 1, 1992
Creator: Madooglu, K.
Partner: UNT Libraries Government Documents Department

(Particle physics)

Description: This report briefly discusses the following topics: rare and forbidden eta meson and muon decays to test the standard model; tests of charge symmetry and isospin invariance; studies of baryon resonances; and exploratory investigations in support of the previous programs. (LSP)
Date: July 1, 1990
Partner: UNT Libraries Government Documents Department