Supersymmetry breaking from superstrings and the gauge hierarchy (open access)

Supersymmetry breaking from superstrings and the gauge hierarchy

The gauge hierarchy problem is reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a classical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated. 39 refs.
Date: July 11, 1990
Creator: Gaillard, M.K. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)
Object Type: Article
System: The UNT Digital Library
Impulse gage development for the 100-200 ktap range (open access)

Impulse gage development for the 100-200 ktap range

Special effects underground test (UGT) material response and source diagnostics data require impulse gages that can be used in the 50--150 ktap range and have equilibrated from electrical and mechanical noise sources within 0.001 s. Such gages were designed, analyzed, and tested under this program. One- and two-dimensional stress propagation calculations were performed and predictions were developed for deformation of the gage specimen cup. These predictions were conservative when compared to gas gun test results. The response of the gage will equilibrate within 5% to its final value within 300 {mu}sec. The impulse delivered to the gages for these tests exceeded 250 ktap. The code and experimental results provides a basis for confidence in the operability of the gage in an actual UGT environment.
Date: July 31, 1990
Creator: Rose, P.C. & Naumann, W.J. (General Research Corp., Santa Barbara, CA (USA). Advanced Technologies Div.)
Object Type: Report
System: The UNT Digital Library
Confined vortex scrubber (open access)

Confined vortex scrubber

The program objective is to demonstrate efficient removal of fine particulates to sufficiently low levels to meet proposed small scale coal combustor emission standards using a cleanup technology appropriate to small scale coal combustors. This to be accomplished using a novel particulate removal device, the Confined Vortex Scrubber (CVS), which consists of a cylindrical vortex chamber with tangential flue gas inlets. The clean gas exit is via vortex finder outlets, one at either end of the tube. Liquid is introduced into the chamber and is confined within the vortex chamber by the centrifugal force generated by the gas flow itself. This confined liquid forms a layer through which the flue gas is then forced to bubble, producing a strong gas/liquid interaction, high inertial separation forces and efficient particulate cleanup. During this quarter a comprehensive series of cleanup experiments have been made for three CVS configurations. The first CVS configuration tested gave very efficient fine particulate removal at the design air mass flow rate (1 MM BUT/hr combustor exhaust flow), but had over 20{double prime}WC pressure drop. The first CVS configuration was then re-designed to produce the same very efficient particulate collection performance at a lower pressure drop. The current CVS …
Date: July 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced coal-fueled industrial cogeneration gas turbine system (open access)

Advanced coal-fueled industrial cogeneration gas turbine system

The objective of the Solar/METC program is to prove the technical, economic, and environmental feasibility of coal-fired gas turbine for cogeneration applications through tests of a Centaur Type H engine system operated on coal fuel throughout the engine design operating range. This quarter, work was centered on design, fabrication, and testing of the combustor, cleanup, fuel specifications, and hot end simulation rig. 2 refs., 59 figs., 29 tabs.
Date: July 1, 1990
Creator: LeCren, R. T.; Cowell, L. H.; Galica, M. A.; Stephenson, M. D. & Wen, C. S.
Object Type: Report
System: The UNT Digital Library
Duct injection technology prototype development: Evaluation of engineering data (open access)

Duct injection technology prototype development: Evaluation of engineering data

The objective of the Duct Injection Technology Prototype Development Project is to develop a sound design basis for applying duct injection technology as a post-combustion SO{sub 2}emissions control method to existing coal-fired power plants. The necessary engineering design and scale-up criteria will be developed for the commercialization of duct injection technology for the control of SO{sub 2} emissions from coal-fired boilers in the utility industry. The primary focus of the analyses summarized in this Topical Report is the review of the known technical and economic information associated with duct injection technology. (VC)
Date: July 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems (open access)

Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems

CRS Sirrine (CRSS) is evaluating a novel IGCC process in which gases exiting the gasifier are burned in a gas turbine combustion system. The turbine exhaust gas is used to generate additional power in a conventional steam generator. This results in a significant increase in efficiency. However, the IGCC process requires development of novel approaches to control SO{sub 2} and NO{sub x} emissions and alkali vapors which can damage downstream turbine components. Ammonia is produced from the reaction of coal-bound nitrogen with steam in the reducing zone of any fixed bed coal gasifier. This ammonia can be partially oxidized to NO{sub x} when the product gas is oxidized in a gas turbine combustor. Alkali metals vaporize in the high-temperature combustion zone of the gasifier and laser condense on the surface of small char or ash particles or on cooled metal surfaces. It these alkali-coated materials reach the gas turbine combustor, the alkali will revaporize condense on turbine blades and cause rapid high temperature corrosion. Efficiency reduction will result. PSI Technology Company (PSIT) was contracted by CRSS to evaluate and recommend solutions for NO{sub x} emissions and for alkali metals deposition. Various methods for NO{sub x} emission control and the potential …
Date: July 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Nuclear structure studies at intermediate energies (open access)

Nuclear structure studies at intermediate energies

This report discusses the following topics: Search for dibaryon resonances; analysis of {sup 208}Pb({pi}{sup {plus minus}},{pi}{sup {plus minus}}) data; analysis of {sup 206,207,208}Pb(p,p{prime}) data; study of transition nuclei by (p,p{prime}); search for recoil free {delta}-production; search for low lying magnetic states; proton nucleus scattering and swelling of nucleons; measurement of spin observables in {sup 28}Si(p,p{prime}); strength of tensor force in nuclei; global analysis of (p,p{prime}) reactions to high spin states in {sup 28}Si and {sup 58}Ni and density dependent modifications; MRS Setup and development; and development of coincidence studies with the MRS.
Date: July 1, 1990
Creator: Hintz, Norton M.
Object Type: Report
System: The UNT Digital Library
Mechanisms and enhancement of flame stabilization (open access)

Mechanisms and enhancement of flame stabilization

None
Date: July 10, 1990
Creator: Law, Chung K.
Object Type: Report
System: The UNT Digital Library
TFE Verification Program semiannual report for the period ending March 31, 1990 (open access)

TFE Verification Program semiannual report for the period ending March 31, 1990

The objective of the semiannual progress report is to summarize the technical results obtained during the latest reporting period. The information presented herein will include evaluated test data, design evaluations, the results of analyses and the significance of results. The program objective is to demonstrate the technology readiness of a TFE suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW(e) range, and a full-power life of 7 years. The TFE Verification Program builds directly on the technology and data base developed in the 1960s and early 1970s in an AEC/NASA program, and in the SP-100 program conducted in 1983, 1984 and 1985. In the SP-100 program, the attractive features of thermionic power conversion technology were recognized but concern was expressed over the lack of fast reactor irradiation data. The TFE Verification Program addresses this concern. 6 refs., 67 figs., 37 tabs.
Date: July 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of a numerical computer code and circuit element models for simulation of firing systems (open access)

Development of a numerical computer code and circuit element models for simulation of firing systems

Numerical simulation of firing systems requires both the appropriate circuit analysis framework and the special element models required by the application. We have modified the SPICE circuit analysis code (version 2G.6), developed originally at the Electronic Research Laboratory of the University of California, Berkeley, to allow it to be used on MSDOS-based, personal computers and to give it two additional circuit elements needed by firing systems--fuses and saturating inductances. An interactive editor and a batch driver have been written to ease the use of the SPICE program by system designers, and the interactive graphical post processor, NUTMEG, supplied by U. C. Berkeley with SPICE version 3B1, has been interfaced to the output from the modified SPICE. Documentation and installation aids have been provided to make the total software system accessible to PC users. Sample problems show that the resulting code is in agreement with the FIRESET code on which the fuse model was based (with some modifications to the dynamics of scaling fuse parameters). In order to allow for more complex simulations of firing systems, studies have been made of additional special circuit elements--switches and ferrite cored inductances. A simple switch model has been investigated which promises to give at …
Date: July 2, 1990
Creator: Carpenter, K.H. (Kansas State Univ., Manhattan, KS (USA). Dept. of Electrical and Computer Engineering)
Object Type: Report
System: The UNT Digital Library
Molecular biological enhancement of coal biodesulfurization. [Rhodococcus rhodochrous] (open access)

Molecular biological enhancement of coal biodesulfurization. [Rhodococcus rhodochrous]

The overall objective of this project is to sue molecular genetics to develop strains of bacteria with enhanced ability to remove sulfur from coal and to obtain data that will allow the performance and economics of a coal biodesulfurization process to be predicted. The work planned for the current quarter (May 1990 to July 1990) includes the following activities: (1) Construct a cloning vector that can be used in Rhodococcus rhodochrous IGTS8 from the small cryptic plasmid found in Rhodococcus rhodochrous ATCC 190607; (2) Develop techniques for the genetic analysis of IGTS8; (3) Continue biochemical experiments, particularly those that may allow the identification of desulfurization-related enzymes; (4) Continue experiments with coal to determine the kinetics of organic sulfur removal.
Date: July 1, 1990
Creator: Kilbane, J. J. & Bielaga, B. A.
Object Type: Report
System: The UNT Digital Library
Task 2: Mild gasification technology development process research unit tests using slipstream sampling, February 1988--March 1990 (open access)

Task 2: Mild gasification technology development process research unit tests using slipstream sampling, February 1988--March 1990

Under USDOE sponsorship, a project team consisting of the Institute of Gas Technology (IGT), Peabody Holding Company, Inc., and Bechtel Group is developing a process for the mild gasification of coal in a 100-pound/hour capacity isothermal process research unit (PRU) at IGT in Chicago. The IGT process is capable of converting bituminous coals to value-added co-products that can open new markets for the US coal industry. The conceptual IGT mild gasification process incorporates an integrated fluidized-/entrained-bed reactor supplying heat indirectly by a combination of char and gas recycle. The use of mild operating conditions (1000{degree} to 1300{degree}F), low pressures (<50 psig), and continuous operation in closed reactors, combined with the sale of value-added co-products, offer an environmentally sound and economical approach to advanced coal utilization. The PRU consists of an 8-inch-ID {times} 8-foot-long fluidized-bed reactor closely coupled to a 4-inch-ID {times} 13-foot-long entrained-bed reactor. The PRU test results have demonstrated process performance, including the effect of coal type and temperature on mild gasification co-product yields and their properties. The fates of the heteroatoms have also been analyzed. 9 refs., 16 figs., 41 tabs.
Date: July 1, 1990
Creator: Knight, R. A.; Gissy, J.; Onischak, M.; Babu, S.P.; Wootten, J. M. & Duthie, R. G.
Object Type: Report
System: The UNT Digital Library
Insolation data manual and direct normal solar radiation data manual (open access)

Insolation data manual and direct normal solar radiation data manual

The Insolation Data Manual presents monthly averaged data which describes the availability of solar radiation at 248 National Weather Service (NWS) stations, principally in the United States. Monthly and annual average daily insolation and temperature values have been computed from a base of 24--25 years of data, generally from 1952--1975, and listed for each location. Insolation values represent monthly average daily totals of global radiation on a horizontal surface and are depicted using the three units of measurement: kJ/m{sup 2} per day, Btu/ft{sup 2} per day and langleys per day. Average daily maximum, minimum and monthly temperatures are provided for most locations in both Celsius and Fahrenheit. Heating and cooling degree-days were computed relative to a base of 18.3 C (65 F). For each station, global {bar K}{sub T} (cloudiness index) values were calculated on a monthly and annual basis. Global {bar K}{sub T} is an index of cloudiness and indicates fractional transmittance of horizontal radiation, from the top of the atmosphere to the earth's surface. The second section of this volume presents long-term monthly and annual averages of direct normal solar radiation for 235 NWS stations, including a discussion of the basic derivation process. This effort is in response …
Date: July 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Multidisciplinary study of phase separation in a supersaturated Ni-Si alloy (open access)

Multidisciplinary study of phase separation in a supersaturated Ni-Si alloy

The subject of {gamma}{prime} precipitation in a Ni-12.5 at. % Si alloy has been studied by modern diffraction and scattering techniques in the small-angle and large angle regimes, and by transmission electron microscopy. Special attention is placed upon the mechanism and kinetic evolution of {gamma}{prime} precipitates as a function of ageing conditions. Methods are shown for the determination of interdiffusion coefficient, the interfacial energy and the coherent solubility. The strain effect, due to lattice mismatch, on the spatial correlation and preferred alignment of precipitates is addressed. Scaling law for the particle growth has been tested against the current theories. Results obtained from the three mutually beneficial techniques are shown to be consistent, thereby allowing an integral view of the phase separation process in this system. 29 refs., 19 figs., 3 tabs.
Date: July 1, 1990
Creator: Chen, Haydn (Illinois Univ., Urbana, IL (USA). Dept. of Materials Science and Engineering) & Epperson, J.E. (Argonne National Lab., IL (USA))
Object Type: Article
System: The UNT Digital Library
Indicators of energy efficiency: An international comparison (open access)

Indicators of energy efficiency: An international comparison

The United States has long been accused of being energy inefficient based on a comparison of energy intensities among the industrialized countries. Energy intensity is commonly measured by computing the ratio of energy use per unit of Gross Domestic Product (GDP). This is not a true measure of efficiency, however, because it does not account for differences in the standard of living, differences in population densities, or other factors. After corrections are made to account for these factors, the United States often appears to be as efficient or more efficient than many of the other industrialized countries. In this analysis the industrialized economies considered are the Group of Seven (G7): the United States, Canada, Japan, France, Italy, West Germany, and the United Kingdom. In summary, since 1970 the United States has improved the efficiency of energy use as much or more than have the other G-7 countries. Frequently, the United States is more efficient in its use of energy than are other G-7 countries. Many of the differences in energy use result from the fact that the United States has the comparative advantage of abundant indigenous energy supplies which have been used to develop large energy intensive but not necessarily …
Date: July 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Power Burst Facility/Boron Neutron Capture Therapy program for cancer treatment, Volume 4, No. 7 (open access)

Power Burst Facility/Boron Neutron Capture Therapy program for cancer treatment, Volume 4, No. 7

This report discusses the monthly progress of the Power Burst Facility/Boron Neutron Capture Therapy (PBF/BNLT) program for cancer treatment. Highlights of the PBF/BNCT Program during July 1990 include progress within the areas of: Gross boron analysis in tissue, blood, and urine; noninvasive boron quantitative determination; analytical radiation transport and interaction modeling for BNCT; large animal model studies; neutron source and facility preparation; administration and common support and PBF operations.
Date: July 1, 1990
Creator: Ackermann, A. L.
Object Type: Report
System: The UNT Digital Library
Reactive Chemical Transport in Ground-Water Hydrology: Challenges to Mathematical Modeling (open access)

Reactive Chemical Transport in Ground-Water Hydrology: Challenges to Mathematical Modeling

For a long time, earth scientists have qualitatively recognized that mineral assemblages in soils and rocks conform to established principles of chemistry. In the early 1960's geochemists began systematizing this knowledge by developing quantitative thermodynamic models based on equilibrium considerations. These models have since been coupled with advective-dispersive-diffusive transport models, already developed by ground-water hydrologists. Spurred by a need for handling difficult environmental issues related to ground-water contamination, these models are being improved, refined and applied to realistic problems of interest. There is little doubt that these models will play an important role in solving important problems of engineering as well as science over the coming years. Even as these models are being used practically, there is scope for their improvement and many challenges lie ahead. In addition to improving the conceptual basis of the governing equations, much remains to be done to incorporate kinetic processes and biological mediation into extant chemical equilibrium models. Much also remains to be learned about the limits to which model predictability can be reasonably taken. The purpose of this paper is to broadly assess the current status of knowledge in modeling reactive chemical transport and to identify the challenges that lie ahead.
Date: July 1, 1990
Creator: Narasimhan, T. N. & Apps, J. A.
Object Type: Article
System: The UNT Digital Library
Experimental study of layer mixing, relative ionic escape velocity, and electron temperature gradients in spherical multilayered targets by XUV spectroscopy (open access)

Experimental study of layer mixing, relative ionic escape velocity, and electron temperature gradients in spherical multilayered targets by XUV spectroscopy

This past year we have undertaken experiments at the University of Rochester's Laboratory for Laser Energetics investigating layer mixing and expansion velocities of spherical targets uniformly irradiated by high intensity laser light. We performed high resolution spectroscopic measurements of spherical plasmas, produced using the Omega laser, and have observed enhanced broadening of XUV emission lines due to the expansion velocities.
Date: July 1, 1990
Creator: Griem, H. R.
Object Type: Report
System: The UNT Digital Library
CEC/USDOE workshop on uncertainty analysis (open access)

CEC/USDOE workshop on uncertainty analysis

Any measured or assessed quantity contains uncertainty. The quantitative estimation of such uncertainty is becoming increasingly important, especially in assuring that safety requirements are met in design, regulation, and operation of nuclear installations. The CEC/USDOE Workshop on Uncertainty Analysis, held in Santa Fe, New Mexico, on November 13 through 16, 1989, was organized jointly by the Commission of European Communities (CEC's) Radiation Protection Research program, dealing with uncertainties throughout the field of consequence assessment, and DOE's Atmospheric Studies in Complex Terrain (ASCOT) program, concerned with the particular uncertainties in time and space variant transport and dispersion. The workshop brought together US and European scientists who have been developing or applying uncertainty analysis methodologies, conducted in a variety of contexts, often with incomplete knowledge of the work of others in this area. Thus, it was timely to exchange views and experience, identify limitations of approaches to uncertainty and possible improvements, and enhance the interface between developers and users of uncertainty analysis methods. Furthermore, the workshop considered the extent to which consistent, rigorous methods could be used in various applications within consequence assessment. 3 refs.
Date: July 1, 1990
Creator: Elderkin, C.E. (Pacific Northwest Lab., Richland, WA (USA)) & Kelly, G.N. (Commission of the European Communities, Brussels (Belgium))
Object Type: Article
System: The UNT Digital Library
Investigation of the ROPE copyright (Recycle Oil Pyrolysis and Extraction) process performance on Sunnyside tar sand (open access)

Investigation of the ROPE copyright (Recycle Oil Pyrolysis and Extraction) process performance on Sunnyside tar sand

The main objectives of this research were to determine the optimum pyrolysis temperature for Sunnyside tar sand and to verify the operability and efficiency of the ROPE process at steady-state conditions for production of feedstock materials. The experiments were conducted in the 2-inch screw pyrolysis reactor (SPR). Four 24-hour tests and one 105-hour test were performed in the 2-inch SPR using Sunnyside tar sand. The 24-hour tests were designed to predict the optimum pyrolysis temperature for oil yield. The 105-hour test was conducted to confirm the optimum pyrolysis temperature with sufficient operating time to reach steady-state conditions with respect to product compositions. The following conclusions can be drawn from the Sunnyside tar sand 2-inch SPR tests: (1) Sunnyside tar sand can be processed without any major operational difficulty by the ROPE process. (2) Oil yields greater than Fischer assay were obtained during the 2-inch SPR tests. Oil yield greater than 80 wt % of the bitumen was obtained from the 105-hr test. (3) The ratio of heavy oil to light product oil is strongly dependent upon the pyrolysis temperature and increases with a decrease in the reaction temperature. The gas yield increases with the increase in pyrolysis temperature but the …
Date: July 1, 1990
Creator: Cha, C. Y.; Johnson, L. A. Jr. & Guffey, F. D.
Object Type: Report
System: The UNT Digital Library
Respiratory tract clearance model for dosimetry and bioassay of inhaled radionuclides (open access)

Respiratory tract clearance model for dosimetry and bioassay of inhaled radionuclides

The ICRP Task Group on Respiratory Tract Models is developing a model to describe the retention and clearance of deposited radionuclides for dose-intake calculations and interpretation of bioassay data. Clearance from each region is treated as competition between mechanical transport, which moves particles to the gastro-intestinal tract and lymph nodes, and the translocation of material to blood. It is assumed that mechanical transport rates are the same for all materials, and that rates of translocation to blood are the same in all regions. Time-dependent clearance is represented by combinations of compartments. Representative values of parameters to describe mechanical transport from the human respiratory tract have been estimated, and guidance is given on the determination of translocation rates. It is emphasized that the current version of the model described here is still provisional. 30 refs.
Date: July 1990
Creator: Bailey, M. R.; Birchall, A.; Cuddihy, R. G.; James, A. C. & Roy, M.
Object Type: Article
System: The UNT Digital Library
Some observations concerning alpha instabilities and driven tokamak reactors (open access)

Some observations concerning alpha instabilities and driven tokamak reactors

While much research is needed to assess the reality and consequences of alpha-induced instabilities, crude transport estimates for the TAE mode indicate that as little as 10 percent of the alpha energy would be deposited in steady-state. Even so, CIT and the ITER technology phase would meet their minimal goals of Q = 5 if only the alphas themselves are ejected and not the fuel itself. Higher gain up to Q {approximately} 20 may be possible in driven reactors of a different design, depending on the effects of aspect ratio and other geometric features on confinement. Very high gain still requires alpha testing. 5 refs.
Date: July 16, 1990
Creator: Fowler, T.K. (California Univ., Berkeley, CA (USA))
Object Type: Report
System: The UNT Digital Library
Hydrogen from renewable resources research (open access)

Hydrogen from renewable resources research

In 1986 the Hawaii Natural Energy Institute (HNEI) and the Florida Solar Energy Center (FSEC) were contracted by the Solar Energy Research Institute (SERI) to conduct an assessment of hydrogen production technologies and economic feasibilities of the production and use of hydrogen from renewable resources. In the 1989/90 period all monies were directed toward research and development with an emphasis on integration of tasks, focusing on two important issues, production and storage. The current year's efforts consisted of four tasks, one task containing three subtasks: Hydrogen Production by Gasification of Glucose and Wet Biomass in Supercritical Water; Photoelectrochemical Production of Hydrogen; Photoemission and Photoluminescence Studies of Catalyzed Photoelectrode Surfaces for Hydrogen Production; Solar Energy Chemical Conversion by Means of Photoelectrochemical (PEC) Methods Using Coated Silicon Electrodes; Assessment of Impedance Spectroscopy Methods for Evaluation of Semiconductor-Electrolyte Interfaces; Solar Energy Conversion with Cyanobacteria; Nonclassical Polyhydride Metal Complexes as Hydrogen Storage Materials. 61 refs., 22 figs., 11 tabs.
Date: July 1, 1990
Creator: Takahashi, P.K. & McKinley, K.R.
Object Type: Report
System: The UNT Digital Library
Energy conservation standards for new federal residential buildings: A decision analysis study using relative value discounting (open access)

Energy conservation standards for new federal residential buildings: A decision analysis study using relative value discounting

This report presents a reassessment of the proposed standard for energy conservation in new federal residential buildings. The analysis uses the data presented in the report, Economic Analysis: In Support of Interim Energy Conservation Standards for New Federal Residential Buildings (June 1988)-to be referred to as the EASIECS report. The reassessment differs from that report in several respects. In modeling factual information, it uses more recent forecasts of future energy prices and it uses data from the Bureau of the Census in order to estimate the distribution of lifetimes of residential buildings rather than assuming a hypothetical 25-year lifetime. In modeling social preferences decision analysis techniques are used in order to examine issues of public values that often are not included in traditional cost-benefit analyses. The present report concludes that the public would benefit from the proposed standard. Several issues of public values regarding energy use are illustrated with methods to include them in a formal analysis of a proposed energy policy. The first issue places a value on costs and benefits that will occur in the future as an irreversible consequence of current policy choices. This report discusses an alternative method, called relative value discounting which permits flexible discounting …
Date: July 2, 1990
Creator: Harvey, C. (Houston Univ., TX (USA). Coll. of Business Administration); Merkhofer, M.M. & Hamm, G.L. (Applied Decision Analysis, Inc., Menlo Park, CA (USA))
Object Type: Report
System: The UNT Digital Library