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A Novel Coal Feeder for Production of Low Sulfur Fuel (open access)

A Novel Coal Feeder for Production of Low Sulfur Fuel

During the past three months, the coal feeding system has been tested and currently undergoing evaluation at the University of Cincinnati. The system consists primarily of an auger feed tube which is used to both convey and provide desulfurization of a high sulfur coal feedstock. The coal is conveyed at temperatures ranging from 350 to 550{degrees}C and under normal atmospheric pressure. Under these mild processing conditions, the coal partially pyrolizes and emits sulfur in the form of hydrogen sulfide while maintaining a relatively high heating value in the char product. The evolved gases are evacuated from the reactor (the feed tube) to another absorbing bed where H{sub 2}S reacts with the sorbent, usually lime or limestone. The resultant sorbent utilization is substantially higher than the values found in current dry scrubbing system and the produced low-sulfur char may then be used in a conventional steam boiler.
Date: January 1, 1990
Creator: Khang, S. J. & Keener, T. C.
Object Type: Report
System: The UNT Digital Library
Health effects models for nuclear power plant accident consequence analysis: Low LET radiation (open access)

Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and other.'' The category, other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent …
Date: January 1, 1990
Creator: Evans, J. S.
Object Type: Report
System: The UNT Digital Library
A Program of FRC Theory Research Annual Report (open access)

A Program of FRC Theory Research Annual Report

At the request of the Office of Fusion Energy, a group of experts was convened on February 6--8, 1990. This group met to assess the world data base on Reversed Field Pinch (RFP) physics, and, further, to assess the role of the ZTH experiment in providing reactor relevant physics understanding for that confinement geometry. This group met, analyzed some of the relevant literature, and heard extensive presentations on the physics of the RFP and the plans for the ZTH and RFX devices. The conclusions of this group of experts are contained in this report.
Date: May 18, 1990
Creator: Krall, Nicholas A.
Object Type: Report
System: The UNT Digital Library
Biological Production of Ethanol From Coal (open access)

Biological Production of Ethanol From Coal

The fermentation pH has been observed to be the key parameter affecting the ratio of ethanol to acetate produced by Clostridium ljungdahlii. The effects of controlled pH on cell growth and product formation by C. ljungdahlii were measured. It was found that cell concentration and acetate concentration increased with pH, while the ethanol concentration was highest at the lower pH. The molar product ratio of ethanol to acetate was 0.74 at pH 4.0, 0.39 at pH 4.5 and 0.12 at pH 5.0. Future experiments will concentrate on studying other important parameters such as agitation rate and nutrients concentrations with controlled pH as a preclude to continuous reactor studies.
Date: January 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Waste Isolation Pilot Plant site environmental report for calendar year 1990 (open access)

Waste Isolation Pilot Plant site environmental report for calendar year 1990

The US Department of Energy (DOE) Waste Isolation Pilot Plant (WIPP) Operational Environmental Monitoring Plan (OEMP) monitors a comprehensive set of parameters in order to detect any potential environmental impacts and establish baselines for future quantitative environmental impact evaluations. Surface water and groundwater, soil, and biotics are measured for background radiation. Nonradiological environmental monitoring activities include meteorological, air quality, soil properties, and the status of the local biological community. Ecological studies focus on the immediate area surrounding the site with emphasis on the salt storage pile, whereas baseline radiological surveillance covers a broader geographic area including nearby ranches, villages, and cities. Since the WIPP is still in a preoperational state, no waste has been received; therefore, certain elements required by Order DOE 5400.1 are not presented in this report. 15 figs. 19 tabs.
Date: January 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Design and operation of an inert gas facility for thermoelectric generator storage (open access)

Design and operation of an inert gas facility for thermoelectric generator storage

While the flight hardware is protected by design from the harsh environments of space, its in-air storage often requires special protection from contaminants such as dust, moisture and other gases. One of these components, the radioisotope thermoelectric generator (RTG) which powers the missions, was deemed particularly vulnerable to pre-launch aging because the generators remain operational at core temperatures in excess of 1000 degrees centigrade throughout the storage period. Any oxygen permitted to enter the devices will react with thermally hot components, preferentially with molybdenum in the insulating foils, and with graphites to form CO/CO{sub 2} gases which are corrosive to the thermopile. It was important therefore to minimize the amount of oxygen which could enter, by either limiting the effective in-leakage areas on the generators themselves, or by reducing the relative amount of oxygen within the environment around the generators, or both. With the generators already assembled and procedures in place to assure minimal in-leakage in handling, the approach of choice was to provide a storage environment which contains significantly less oxygen than normal air. 2 refs.
Date: January 1, 1990
Creator: Goebel, C. J.
Object Type: Article
System: The UNT Digital Library
FLOWTRAN benchmarking with onset of flow instability data from 1988 Columbia University single-tube OFI experiment (open access)

FLOWTRAN benchmarking with onset of flow instability data from 1988 Columbia University single-tube OFI experiment

Benchmarking FLOWTRAN, Version 16.2, with an Onset of Significant Voiding (OSV) criterion against measured Onset of Flow Instability (OFI) data from the 1988--89 Columbia University downflow tests has shown that FLOWTRAN with OSV is a conservative OFI predictor. Calculated limiting flow rates based on the Savannah River Site (SRS) OSV criterion were always higher than the measured flow rates at OFI. This work supplements recent FLOWTRAN benchmarking against 1963 downflow tests at Columbia University and 1988 downflow tests at the Heat Transfer Laboratory. These studies provide confidence that using FLOWTRAN with an OSV based criterion for SRS reactor limits analyses will generate operating limits that are conservative with respect to OFI, the criterion selected to prevent fuel damage.
Date: June 1, 1990
Creator: Chen, K.; Paul, P. K. & Barbour, K. L.
Object Type: Report
System: The UNT Digital Library
H-Area Seepage Basins (open access)

H-Area Seepage Basins

During the third quarter of 1990 the wells which make up the H-Area Seepage Basins (H-HWMF) monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, nonvolatile beta, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, nonvolatile beta, trichloroethylene (TCE), tetrachloroethylene, lead, cadmium, arsenic, and total radium.
Date: December 1, 1990
Creator: Stejskal, G.
Object Type: Report
System: The UNT Digital Library
FY 90 annual research plan (open access)

FY 90 annual research plan

The National Institute for Petroleum and Energy Research (NIPER) was established by the DOE to perform contract research for government and industrial clients. The emphasis of the DOE program is immediate near- and mid-term concerns of domestic oil and gas producibility. Its primary purpose is to improve the fundamental understanding of domestic oil and gas resources and the chemical, physical, and biological phenomena that govern the occurrence and recovery of these resources in addition to their associated environmental issues. The near-term objective of the DOE program is to maintain access to resources presently being produced in domestic oil and gas fields, and to decrease the rate of decline of domestic production. NIPER projects in chemical flooding, gas injection, steam injection, and microbial EOR address near-term concerns of domestic oil production. Further, problems associated with the utilization of heavier fossil feedstocks are being addressed. The mid-term objective of the DOE program is to maximize the recovery efficiency of discovered oil and gas through improved understanding of the resource and to develop advanced extraction and instrumentation techniques. The objective also emphasizes an expanded understanding of the environment. NIPER projects dealing with the quantification of reservoir heterogeneities, pore structure analysis, and fluid flow …
Date: January 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
A study of tau decays of the W boson at CDF (Collider Detector at Fermilab) (open access)

A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)

A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.
Date: January 3, 1990
Creator: Gladney, L. D.
Object Type: Article
System: The UNT Digital Library
Glossary: Carbon dioxide and climate (open access)

Glossary: Carbon dioxide and climate

This Glossary contains definitions of selected CO{sub 2}-related terms as well as tables containing information related to CO{sub 2} and climate. Each term is defined with an emphasis on its relationship to CO{sub 2} and climate. Many of the definitions are then followed by a more detailed description of the term and its use. References to the literature from which the definitions were taken are listed at the end of the Glossary.
Date: August 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Comparison of TRAC and RELAP5 reactor system calculations for a DEGB LOCA in K-14. 1 (open access)

Comparison of TRAC and RELAP5 reactor system calculations for a DEGB LOCA in K-14. 1

A comparison of TRAC and RELAP5 predictions of steady-state and DEGB LOCA results (FI phase) for K-14.1 has been made. Both codes had been previously benchmarked against 1985 L Reactor AC Flow data and were under configuration control. The purpose of the code-to-code comparison is to provide insight on the transient uncertainty in TRAC plenum and tank bottom plenum pressures. The comparisons focus on LOCA results between 0.5 and 2.0 s, which is the primary period of interest for Flow Instability (FI) limits.
Date: September 1, 1990
Creator: Griggs, D.P. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Liebmann, M.L. (Wais and Associates (United States))
Object Type: Report
System: The UNT Digital Library
NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts (open access)

NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Methods of preparation of the copper, cobalt, and titanium catalysts were outlined. The catalyst samples were then analyzed through nuclear magnetic and nuclear quadrupole resonance.
Date: February 1, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The product consistency test for the DWPF wasteform (open access)

The product consistency test for the DWPF wasteform

The preliminary specifications on the glass wasteform to be produced by the Defense Waste Processing Facility (DWPF) require extensive characterization of the glass product both before actual production begins and then during production. To aid in this characterization, a leach test was needed that was easily reproducible, could be performed remotely on highly radioactive samples, and could yield results rapidly. Several standard leach tests were examined with a variety of test configurations. Using existing tests as a starting point, the DWPF Product Consistency Test (PCT) was developed in which crushed glass samples are exposed to 90{degrees}C deionized water for seven days. Based on extensive testing, including a seven-laboratory round robin and confirmatory testing with radioactive samples, the PCT is very reproducible, yields reliable results rapidly, and can be performed in shielded cell facilities with radioactive samples.
Date: January 1, 1990
Creator: Jantzen, Carol M. & Bibler, N. E.
Object Type: Article
System: The UNT Digital Library
A study of steady-state steam-water counterflow in porous media (open access)

A study of steady-state steam-water counterflow in porous media

Vapor-liquid counterflow in porous media arises in processes such as heat pipes, oil recovery and geothermal systems. Previous studies analysed these phenomena in separate contexts. This paper presents a unified description from which previous models result as limiting cases. The analysis includes capillarity, heat conduction, and Kelvin effects. The importance of each term to various processes is examined. Significantly, it is found that the critical heat flux is not constant but increases with decreasing permeability. A threshold permeability is identified below which steady states may not exist. Analogous conclusions are reached regarding liquid-dominated geothermal systems. 24 refs., 15 figs.
Date: February 1, 1990
Creator: Satik, C.; Parlar, M. & Yortsos, Y.C.
Object Type: Report
System: The UNT Digital Library
The electronics and data acquisition system for the Wire Imaging Synchrotron Radiation Detector at the SLC (Stanford Linear Collider) (open access)

The electronics and data acquisition system for the Wire Imaging Synchrotron Radiation Detector at the SLC (Stanford Linear Collider)

The Stanford Linear Collider (SLC) located at the Stanford Linear Accelerator Center collides electrons and positrons produced in the linear accelerator pulse by pulse. We determine the energy of each beam by measuring the angle of deflection of the beam in the SLC extraction lines. Each extraction line consists of two bending magnets that produce synchrotron radiation, and a spectrometer analyzing magnet that deflects the beam. We detect the synchrotron light by using the emission of electrons produced by Compton scattering off Cu-Be wires. We detect the {approximately} 180 fC of charge on the wire by using the electronics system described in this paper. We also discuss the performance of the system, including the equivalent noise charge, cross-talk between channels, stability, and reliability. 4 refs., 7 figs.
Date: January 1, 1990
Creator: Rouse, F.; Briggs, D.D. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)); Gomez, J.J.; Von Zanthier, C. & Kent, J. (California Univ., Santa Cruz, CA (USA))
Object Type: Article
System: The UNT Digital Library
An optimized algorithm for solving the nodal diffusion method on shared memory multiprocessors (open access)

An optimized algorithm for solving the nodal diffusion method on shared memory multiprocessors

Nodal methods play a special role in reactor physics calculations. In recent papers the high computational efficiency of nodal methods has been established and the development of more efficient algorithms tailored to the advanced architectures of modern day computers proposed. The rapidly changing architectures of today's computer influence the way codes have to be programmed so that reasonable speed up and efficiency are attained. We have applied these concepts in solving the one-group neutron diffusion equation in two-dimensional geometry on parallel computers like the Intel iPSC/2 hypercube and the Sequent Balance 8000. The efficiency of the hypercube for the neutron diffusion equation is highly determined by the message passing scheme; on the other hand, on a shared memory processor like the Sequent, it is dependent on the manipulation of variables in shared memory. In this paper, we present a scheme on shared memory processors which produces very high computing efficiencies in agreement with Amdahl's law. 6 refs., 1 fig.
Date: January 1, 1990
Creator: Kirk, B.L. & Azmy, Y.Y.
Object Type: Article
System: The UNT Digital Library
Internal dosimetry technical basis manual (open access)

Internal dosimetry technical basis manual

The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.
Date: December 20, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
A many particle-tracking detector with drift planes and segmented cathode readout (open access)

A many particle-tracking detector with drift planes and segmented cathode readout

We describe the design and performance of a detector system for tracking charged particles in an environment of high track density and rates up to 1 MHz. The system operates in the forward spectrometer of the BNL Heavy Ion experiment E814 and uses principles of general interest in high rate, high multiplicity applications such as at RHIC or SSC. We require our system to perform over a large dynamic range, detecting singly charged particles as well as fully ionized relativistic {sup 28}Si. Results on gas gain saturation, {delta}-ray suppression, and overall detector performance in the presence of a 14.6 GeV/nucleon {sup 28}Si beam and a 14 GeV proton beam are presented. 6 refs., 9 figs.
Date: January 1, 1990
Creator: Fischer, J.; Lissauer, D.; Ludlam, T.; Makowiecki, D.; O'Brien, E.; Radeka, V. et al.
Object Type: Article
System: The UNT Digital Library
Design of a full scale model fuel assembly for full power production reactor flow excursion experiments (open access)

Design of a full scale model fuel assembly for full power production reactor flow excursion experiments

A novel full scale production reactor fuel assembly model was designed and built to study thermal-hydraulic effects of postulated Savannah River Site (SRS) nuclear reactor accidents. The electrically heated model was constructed to simulate the unique annular concentric tube geometry of fuel assemblies in SRS nuclear production reactors. Several major design challenges were overcome in order to produce the prototypic geometry and thermal-hydraulic conditions. The two concentric heater tubes (total power over 6 MW and maximum heat flux of 3.5 MW/m{sup 2}) (1.1E+6 BTU/(ft{sup 2}hr)) were designed to closely simulate the thermal characteristics of SRS uranium-aluminum nuclear fuel. The paper discusses the design of the model fuel assembly, which met requirements of maintaining prototypic geometric and hydraulic characteristics, and approximate thermal similarity. The model had a cosine axial power profile and the electrical resistance was compatible with the existing power supply. The model fuel assembly was equipped with a set of instruments useful for code analysis, and durable enough to survive a number of LOCA transients. These instruments were sufficiently responsive to record the response of the fuel assembly to the imposed transient.
Date: January 1, 1990
Creator: Nash, C. A. (Westinghouse Savannah River Co., Aiken, SC (United States)); Blake, J. E. & Rush, G. C. (Babcock and Wilcox Co., Alliance, OH (United States))
Object Type: Article
System: The UNT Digital Library
Pseudorapidity densities and fluctuations in central sup 32 S interactions at 200A GeV (open access)

Pseudorapidity densities and fluctuations in central sup 32 S interactions at 200A GeV

Observations of heavy ion interactions at the highest available accelerator energies provide essential information for the analysis and interpretation of cosmic ray interactions. We report on an experiment in which emulsion chamber detectors were exposed to beams of 200A GeV {sup 32}S ions at the CERN SPS. We present statistical features of pseudorapidity distributions from central collisions in the experimental sample and compare them with the predictions from the Lund Model (FRITIOF) which contains only conventional physics. 8 refs., 3 figs.
Date: January 1, 1990
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Considerations for high-brightness electron sources (open access)

Considerations for high-brightness electron sources

Particle accelerators are now used in many areas of physics research and in industrial and medical applications. New uses are being studied to address major societal needs in energy production, materials research, generation of intense beams of radiation at optical and suboptical wavelengths, treatment of various kinds of waste, and so on. Many of these modern applications require a high intensity beam at the desired energy, along with a very good beam quality in terms of the beam confinement, aiming, or focusing. Considerations for ion and electron accelerators are often different, but there are also many commonalties, and in fact, techniques derived for one should perhaps more often be considered for the other as well. We discuss some aspects of high-brightness electron sources here from that point of view. 6 refs.
Date: January 1, 1990
Creator: Jameson, Robert A.
Object Type: Article
System: The UNT Digital Library
A bulk niobium superconducting quarter wave resonator (open access)

A bulk niobium superconducting quarter wave resonator

A bath-cooled all-niobium 160 MHz quarter wave resonator prototype was constructed and tested. The objective of this research has been the development of a high performance accelerating element with {beta}{sub opt} {approx equal} 0.11 for the ALPI linac at the Laboratori Nazionali di Legnaro. The design of this resonator was based upon a previous 150 MHz model, with minor changes due to the different frequency and to modified welding procedure. An accelerating field of 5 MV/m was achieved at a power dissipation of 10 W and the low power Q was 2.4 {times} 10{sup 8}. The resonator could dissipate 70 W of power without thermal breakdown. 16 refs., 2 figs., 1 tab.
Date: January 1, 1990
Creator: Ben-Zvi, Ilan; Chiaveri, E.; Elkonin, B. V.; Facco, A. & Sokolowski, J. S.
Object Type: Article
System: The UNT Digital Library
Negative ion-based neutral injection on DIII-D (open access)

Negative ion-based neutral injection on DIII-D

High energy negative ion-based neutral beam injection is a strong candidate for heating and non-inductive current drive in tokamaks. Many of the questions related to the physics and engineering of this technique remain unanswered. In this paper, we consider the possibility of negative ion-based neutral beam injection on DIII-D. We establish the desired parameter space by examining physics trades. This is combined with potential design constraints and a survey of component technology options to establish an injector concept. Injector performance is estimated assuming particular component technologies, and concept flexibility with respect to incorporating alternate technologies is described. 9 refs., 6 figs., 4 tabs.
Date: January 1, 1990
Creator: Stewart, L. D.; Bhadra, D. K.; Colleraine, A. P. & Kim, J.
Object Type: Article
System: The UNT Digital Library