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Autoionization of Be-like ions following double electron capture in C sup 4+ , O sup 6+ and Ne sup 8+ ions (open access)

Autoionization of Be-like ions following double electron capture in C sup 4+ , O sup 6+ and Ne sup 8+ ions

This paper describes electron emission following the autoionization of doubly excited states in Be-like ions. The Be-like Auger states are produced by two electron capture in slow C{sup 4+}, O{sup 6+} and Ne{sup 8+} ions. These measurements were performed by means of high resolution Auger electron spectroscopy on different target gases and at different projectile energies. Line assignments and relative cross sections are given for the investigated doubly excited states and the excitation mechanism is discussed. 15 refs., 16 figs., 4 tabs.
Date: September 11, 1990
Creator: McDonald, J.W.
System: The UNT Digital Library
Deactivation by Carbon of Iron Catalysts for Indirect Liquefaction (open access)

Deactivation by Carbon of Iron Catalysts for Indirect Liquefaction

This report describes recent progress in a fundamental, three-year investigation of carbon formation and its effects on the activity and selectivity of promoted iron catalysts for Fischer-Tropsch (FT) synthesis, the objectives of which are: determine rates and mechanisms of carbon deactivation of unsupported Fe and Fe/K catalysts during CO hydrogenation over a range of CO concentrations, CO:H{sub 2} ratios, and temperatures; model the rates of deactivation of the same catalysts in fixed-bed reactors. During the thirteenth quarter design of software for a computer-automated reactor system to be used in the kinetic and deactivation studies was continued. Further progress was made toward the completion of the control language, control routines, and software for operating this system. Progress was also made on the testing of the system hardware and software. H{sub 2} chemisorption capacities and activity selectivity data were also measured for three iron catalysts promoted with 1% alumina. 47 refs., 8 figs., 1 tab.
Date: October 11, 1990
Creator: Bartholomew, C. H.
System: The UNT Digital Library
End Cap Calorimeter Inner Hadronic Module Installation (open access)

End Cap Calorimeter Inner Hadronic Module Installation

The fixture used to hold the IH module while the EC Calorimeter is pul led over it consists of two tripod frames with a double wide flange between them. The two tripods have legs made of 6-inch Schedule 40 pipe, these legs are tied together with 2-inch Schedule 40 pipe. One of the legs sits on and is attached to a box made of 3/4-inch plates. The fixture was analyzed using ANSYS. The element used was a 3-D beam (STIF4). Equivalent properties were figured for the double wide flange. The legs of the tripods were constrained in the Y direction (vertical). The box at the bottom of the tripod leg was not used in this analysis, the leg was constrained at the point of attachment to the box. The cross beam was loaded at two points representing the IH load. The reaction force at the point where the tripod leg attaches to the box was then used in an analysis of the box itself. The box was modeled using plate elements (STIF63). The bottom of the box was constrained in the Y (vertical) direction. The top of the box was loaded in roughly a circular area to represent the pipe …
Date: October 11, 1990
Creator: Stredde, H. J.
System: The UNT Digital Library
Establishment and maintenance of a coal sample bank and data base (open access)

Establishment and maintenance of a coal sample bank and data base

In this Project Status Report for 7/9/89--10/8/89, results of a comparative study of coal sample deterioration in several container types were presented. In April 1990, one year after the initial analyses, the set of analyses was repeated on the most important container types. The new results are included in Table 2. During the current reporting period a total of 42 data printouts were distributed. In addition, 7 special data requests were fulfilled by either search/sort and printout or creation of a data disk, resulting in distribution of limited information on 2083 samples. Several preliminary requests for Sample Bank and Data Base information and price quotations have also been handled.
Date: July 11, 1990
Creator: Davis, A.
System: The UNT Digital Library
Establishment and maintenance of a coal sample bank and data base. [Quarterly] project status report, April 9, 1990--July 8, 1990 (open access)

Establishment and maintenance of a coal sample bank and data base. [Quarterly] project status report, April 9, 1990--July 8, 1990

In this Project Status Report for 7/9/89--10/8/89, results of a comparative study of coal sample deterioration in several container types were presented. In April 1990, one year after the initial analyses, the set of analyses was repeated on the most important container types. The new results are included in Table 2. During the current reporting period a total of 42 data printouts were distributed. In addition, 7 special data requests were fulfilled by either search/sort and printout or creation of a data disk, resulting in distribution of limited information on 2083 samples. Several preliminary requests for Sample Bank and Data Base information and price quotations have also been handled.
Date: July 11, 1990
Creator: Davis, A.
System: The UNT Digital Library
The Flux and Recovery of Bioactive Substances in the Surface Sediments of Deep Basins Off Southern California (open access)

The Flux and Recovery of Bioactive Substances in the Surface Sediments of Deep Basins Off Southern California

Sediment microbial community biomass and activity in Santa Monica Basin, a nearshore basin in the California Continental Borderland, were examined in October 1985, 1986 and 1987, May 1986, April 1987 and January 1990. Millimeter-scale ATP profiles and incubation of intact cores with {sup 3}H-adenine indicated a high-biomass interface microbial population in the low-oxygen central basin, which was absent in samples from the basin slope sediments. A majority of microbial activity and organic matter mineralization occurred in the top cm of sediment. Comparison of measured ATP and total organic carbon profiles suggest that the C:ATP ratio (wt:wt) ranges between 47:1 and 77:1 in central basin interfacial populations, substantially lower than reported for other aquatic environments. Carbon production estimated from DNA synthesis measurements via {sup 3}H-adenine incorporation was compared with TCO{sub 2} fluxes measured by in situ benthic chamber experiments. Within the uncertainty of the C:ATP ratio, an overall microbial carbon assimilation efficiency of 75--90% was indicated. The low C:ATP ratios and high carbon assimilation efficiencies significantly affect estimates of microbial growth and respiration and are substantially different than those often assumed in the literature. These results suggest that without independent knowledge of these ratios, the uncertainty in tracer-derived microbial growth and …
Date: June 11, 1990
Creator: Jahnke, R. A.
System: The UNT Digital Library
Gradient Errors and Correction System Summary (open access)

Gradient Errors and Correction System Summary

None
Date: April 11, 1990
Creator: H., Hahn
System: The UNT Digital Library
Guidelines for structural bolting in accordance with the AISC (American Institute of Steel Construction) eighth edition manual of steel construction'' (open access)

Guidelines for structural bolting in accordance with the AISC (American Institute of Steel Construction) eighth edition manual of steel construction''

This paper specifies the usage of structural bolts in terms of their design, selection and application, in accordance with the American Institute of Steel Construction (AISC) Eighth Edition. Manual of Steel Construction.'' 1 tab.
Date: May 11, 1990
Creator: Western, J. L. & Johns, D. M.
System: The UNT Digital Library
An information-theoretic look at branch-prediction (open access)

An information-theoretic look at branch-prediction

Accurate branch-prediction is necessary to utilize deeply pipelined and Very Long Instruction-Word (VLIW) architectures. For a set of program traces we show the upper limits on branch predictability, and hence machine utilization, for important classes of branch-predictors using static (compiletime) and dynamic (runtime) program information. A set of optimal superpredictors'' is derived from these program traces. These optimal predictors compare favorably with other proposed methods of branch-prediction. 3 refs., 5 figs., 12 tabs.
Date: September 11, 1990
Creator: Ponder, C.G. (Lawrence Livermore National Lab., CA (USA)) & Shebanow, M.C. (Motorola, Inc., Austin, TX (USA))
System: The UNT Digital Library
Mathematical modelling of part voltage and weld current in resistance welders (open access)

Mathematical modelling of part voltage and weld current in resistance welders

A mathematical model is presented to describe the part voltage and weld current that occur in a single-phase resistance welder. Developing an accurate model of part voltage and current is the first step toward understanding instrumentation, testing, calibration, and measurement requirements. Measurement requirements for dynamic part resistance, calculated from these basic process variables, can ultimately be determined using this analysis. This model utilizes electrical characteristics of the welder, power system, and parts, as well as geometric parameters of voltage-sensing wires to describe the resultant time functions. The complete equivalent circuit involves many resistive and inductive components in the welder primary and secondary circuits. These components are reduced to a simple equivalent circuit to obtain a closed-form solution for part voltage and weld current time functions. Actual measurements were acquired from a welder using a constant resistance load to verify accuracy of the model. Accuracy of the model is estimated to be within the measurement uncertainty and is, in general, approximately {plus minus}3% for current and {plus minus}5% for part voltage. Pertinent limitations of the model's accuracy and range of applications are also discussed briefly. 28 refs., 10 figs.
Date: September 11, 1990
Creator: Destefan, D.E.
System: The UNT Digital Library
Mechanical support for straw tubes (open access)

Mechanical support for straw tubes

A design is proposed for mounting a large number of straw tubes to form an SSC central tracking chamber. The assembly is precise and of very low mass. The fabrication is modular and can be carried out with a minimum of tooling and instrumentation. Testing of modules is possible prior to the final assembly. 4 figs.
Date: March 11, 1990
Creator: Joestlein, H.
System: The UNT Digital Library
Opto-mechanical support services. Final report (open access)

Opto-mechanical support services. Final report

This subcontract was for Optomec`c support of the Los Alamos National Laboratory`s (LANL`s) Group MEE-12 in the technical specialty area of opto-mechanical design, engineering and fabrication. Two individual tasks were defined by MEE-12 and completed by Optomec personnel. Edward J. Yavornik acted as Principal Investigator on the Wire and Fluorescent Fiber Offset Grid (WAFFOG) for the Neutral Particle Beam (NPB) GTA (Ground Test Accelerator) Experiment, and Thomas Swann acted as Principal Investigator on the ESS-7 Photometers Project. Some hardware was procured/fabricated for the ESS-7 Photometer task, however, most of the work consisted of design and engineering support resulting in drawings and specifications which were prepared by MEE-12 personnel. There were no technical papers or patents generated by Optomec personnel as a result of this work, and all work defined in the contract was completed.
Date: June 11, 1990
Creator: unknown
System: The UNT Digital Library
Petroleum marketing monthly, September 1990. [Contains Glossary] (open access)

Petroleum marketing monthly, September 1990. [Contains Glossary]

This report is designed to give information and statistical data about a variety of crude oils and refined petroleum products. The publication provides statistics on crude oil costs and refined petroleum products sales for use by industry, government, private sector analysts, education institutions, and consumers. Data on crude oil include the domestic first purchase price, the f.o.b. and landed cost of imported crude oil, and the refiners' acquisition cost of crude oil. Sales data for motor gasoline, distillates, residuals, aviation fuels, kerosene, and propane are presented. 12 figs., 55 tabs.
Date: December 11, 1990
Creator: unknown
System: The UNT Digital Library
Photoionization and electron transfer in ionic crystals (open access)

Photoionization and electron transfer in ionic crystals

Three lines of work have been completed since our previously submitted proposal. These are: spectroscopy of Ce{sup 3+} {minus} Na{sup +} pairs in CaF{sub 2} and SrF{sub 2}, photoionization studies of Sm{sup 2+}, Eu{sup 2+} and Yb{sup 2+} in CaF{sub 2} and SrF{sub 2}; and infrared-detected two-photon spectroscopy of MgO:Ni{sup 2+}, and other two-photon spectroscopy studies. These are discussed in this report.
Date: September 11, 1990
Creator: McClure, D.S.
System: The UNT Digital Library
(Resonance ionization spectroscopy) (open access)

(Resonance ionization spectroscopy)

J. P. Young attended the Fifth International Symposium on Resonance Ionization Spectroscopy and presented an invited oral presentation on research he and coworkers had carried out in applying diode lasers to resonance ionization mass spectrometry. A summary of the conference is given along with an assessment of some of the presentations that the author found of interest. Young also visited Professor Marassi at the University of Camerino to present a seminar and discuss mutual interests in a new molten salt research project of the author. Some of the studies at Camerino are described. Ideas concerning the author's research that came from private discussions are also presented here.
Date: October 11, 1990
Creator: Young, J.P.
System: The UNT Digital Library
(Resonance ionization spectroscopy and its applications) (open access)

(Resonance ionization spectroscopy and its applications)

The Fifth International Symposium in Resonance Ionization Spectroscopy and Its Applications was attended. The Joint Research Centre of the European Communities at Ispra, Italy was also visited. The traveler presented an invited talk, chaired a meeting session and gave an impromptu presentation on how current laser technology limits the development of commercial instrumentation based upon Resonance Ionization Spectroscopy. The conference was truely international with scientists from 19 countries and less than 1/4 from the US. The meeting also provided a health mixture of experimentalists and theoreticians. Technical developments reported included the use of electric field ionization from laser prepared Rydberg states as a way to reduce background signals and commercial development of an optical parametric oscillator for replacing pulsed dye laser. A speaker from the Soviet Union suggested their willingness to market hardware they have developed based upon the resonance ionization technique.
Date: October 11, 1990
Creator: Ramsey, J. M.
System: The UNT Digital Library
RHIC Ring Element Nomenclature System (open access)

RHIC Ring Element Nomenclature System

None
Date: October 11, 1990
Creator: Hahn, H.; Rufer, C. & Sondericker, J.
System: The UNT Digital Library
The US petroleum refining industry in the 1980's (open access)

The US petroleum refining industry in the 1980's

As part of the EIA program on petroleum, The US Petroleum Refining Industry in the 1980's, presents a historical analysis of the changes that took place in the US petroleum refining industry during the 1980's. It is intended to be of interest to analysts in the petroleum industry, state and federal government officials, Congress, and the general public. The report consists of six chapters and four appendices. Included is a detailed description of the major events and factors that affected the domestic refining industry during this period. Some of the changes that took place in the 1980's are the result of events that started in the 1970's. The impact of these events on US refinery configuration, operations, economics, and company ownership are examined. 23 figs., 11 tabs.
Date: October 11, 1990
Creator: unknown
System: The UNT Digital Library
Winter Fuels Report: Week Ending October 5, 1990 (open access)

Winter Fuels Report: Week Ending October 5, 1990

The Winter Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and state and local governments on the following topics: distillate fuel oil net production, imports and stocks for all PADD's and product supplied on a US level; propane net production, imports and stocks for Petroleum Administration for Defense Districts (PADD) I, II, and III; natural gas supply and disposition and underground storage, for the United States and consumption for all PADD's; residential and wholesale pricing data for propane and heating oil for those states participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the United States and selected cities; and US total heating degree-days by city. This report will be published weekly by the EIA starting the first week in October 1990 and will continue until the first week in April 1991. The data will also be electronically after 5:00 p.m. on Thursday during the heating season through the EIA Electronic Publication System (EPUB). See page ii for details. 12 tabs.
Date: October 11, 1990
Creator: unknown
System: The UNT Digital Library
X-ray diffraction measurement of residual stresses in delta plutonium (open access)

X-ray diffraction measurement of residual stresses in delta plutonium

Residual stresses in delta plutonium can be measured by the x-ray diffractometer method. This was accomplished with the aid of an experimental tantalum x-ray target. Preliminary experiments are encouraging and indicate that stresses may be determined precisely and rapidly. Future work will involve determination of x-ray elastic constants, instrument calibration with stress-free standards, higher x-ray power and more sophisticated monochromatization methods. 4 refs., 4 figs., 1 tab.
Date: September 11, 1990
Creator: Steinmeyer, P.A.
System: The UNT Digital Library