The coordination and atom transfer chemistry of titanium porphyrin complexes (open access)

The coordination and atom transfer chemistry of titanium porphyrin complexes

Preparation, characterization, and reactivity of ({eta}{sup 2}- alkyne)(meso-tetratolylpoprphrinato)titanium(II) complexes are described, along with inetermetal oxygen atom transfer reactions involving Ti(IV) and Ti(III) porphyrin complexes. The {eta}{sup 2}- alkyne complexes are prepared by reaction of (TTP)TiCl{sub 2} with LiAlH{sub 4} in presence of alkyne. Structure of (OEP)Ti({eta}{sup 2}-Ph-C{triple_bond}C-Ph) (OEP=octaethylporphryin) was determined by XRD. The compounds undergo simple substitution to displace the alkyne and produce doubly substituted complexes. Structure of (TTP)Ti(4-picoline){sub 2} was also determined by XRD. Reaction of (TTP)Ti{double_bond}O with (OEP)Ti-Cl yields intermetal O/Cl exchange, which is a one-electron redox process mediated by O atom transfer. Also a zero-electron redox process mediated by atom transfer is observed when (TTP)TiCl{sub 2} is reacted with (OEP)Ti{double_bond}O.
Date: November 5, 1993
Creator: Hays, J. A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Parameterization of Convective Clouds Mesoscale Convective Systems, and Convective-Generated Cirrus. Final Report, September 15, 1990--October 31, 1993 (open access)

Parameterization of Convective Clouds Mesoscale Convective Systems, and Convective-Generated Cirrus. Final Report, September 15, 1990--October 31, 1993

The overall goal of this research is to develop a scheme to parameterize diabatic heating, moisture/water substance, and momentum transports, and precipitation from mesoscale convective systems (MCSs) for use in general circulation models (GCMs). Our approach is to perform explicit cloud-resolving simulations of MCSs in the spirit of the GEWEX Cloud Systems Study (GCSS), by using the Regional Atmospheric Modeling System (RAMS) developed at Colorado State University (CSU). We then perform statistical analyses (conditional sampling, ensemble-averages, trajectory analyses) of simulated MCSs to assist in fabricating a parameterization scheme, calibrating coefficients, and provide independent tests of the efficacy of the parameterization scheme. A cloud-resolving simulation of ordinary cumulonimbi forced by sea breeze fronts has been completed. Analysis of this case and comparison with parameterized convection simulations has resulted in a number of refinements in the scheme. Three three-dimensional, cloud-resolving simulations of MCSs have been completed. Statistical analyses of model-output data are being performed to assist in developing a parameterization scheme of MCSs in general circulation models.
Date: November 5, 1993
Creator: Cotton, W. R.
Object Type: Report
System: The UNT Digital Library
Relativistic heavy-ion collisions. 1993 annual report (open access)

Relativistic heavy-ion collisions. 1993 annual report

This is a brief report on the work done last year from November 1992 to October 1993. Out of the various areas of research proposed for the three-year period 1993--96, we have successfully carried out investigation in three topics: quark-hadron phase transition, hadron production, and multifractal structure. The results are summarized.
Date: November 5, 1993
Creator: Hwa, R. C.
Object Type: Report
System: The UNT Digital Library
Short-Term Energy Outlook: Quarterly projections. Fourth quarter 1993 (open access)

Short-Term Energy Outlook: Quarterly projections. Fourth quarter 1993

The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The forecast period for this issue of the Outlook extends from the fourth quarter of 1993 through the fourth quarter of 1994. Values for the third quarter of 1993, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data are EIA data published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications.
Date: November 5, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Environmental Release Prevention and Control Plan (ERP and CP) annual review and update for 1993 (open access)

Environmental Release Prevention and Control Plan (ERP and CP) annual review and update for 1993

In the Environmental Release Prevention and Control Plan (ERP and CP), WSRC made a commitment to conduct the following follow-up activities and actions: (1) Complete the action items developed in response to the findings and recommendation of the Environmental Release Prevention Taskteam (WSRC-RP-92-356). (2) Complete all batch and continuous release procedure revisions to incorporate the attributes that WSRC senior management required of each procedure. (3) DOE-SR Assistance Managers and WSRC counterparts to reach consensus and closure on the identified engineered solutions documented in the ERP and CP, develop and drive implementation of facility changes per the agreements. (4) Continue to analyze releases and monitor performance in accordance with the ERP and CP, and utilize the ALARA Release Guides Committee to drive improvements. (5) Conduct annual re-evaluations of the cost benefit analyses of the identified engineered solutions, and identify new options and alternatives for each outfall in response to site mission and facility changes. This report documents the efforts that have been completed over the past year in response to these commitments.
Date: October 5, 1993
Creator: Jannik, G.T.; Mamatey, A. & Arnett, M.
Object Type: Report
System: The UNT Digital Library
General design of the layout for the Advanced Photon Source beamline front ends (open access)

General design of the layout for the Advanced Photon Source beamline front ends

In the first phase of construction, sixteen insertion device beamline front ends and sixteen bending magnet beamline front ends will be built by 1995 for the Advanced Photon Source (APS). Designs for these front ends have been completed. In this paper, the particular designs and specifications as well as the optical and bremsstrahlung ray-tracing analysis for the APS front ends are presented.
Date: October 5, 1993
Creator: Shu, D. & Kuzay, T. M.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 18, Number 76, Pages 6769-6863, October 5, 1993 (open access)

Texas Register, Volume 18, Number 76, Pages 6769-6863, October 5, 1993

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: October 5, 1993
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Anaerobic biprocessing of low rank coals. Final technical report, September 12, 1990--August 10, 1993 (open access)

Anaerobic biprocessing of low rank coals. Final technical report, September 12, 1990--August 10, 1993

Coal solubilization under aerobic conditions results in oxygenated coal product which, in turn, makes the coal poorer fuel than the starting material. A novel approach has been made in this project is to remove oxygen from coal by reductive decarboxylation. In Wyodak subbituminous coal the major oxygen functionality is carboxylic groups which exist predominantly as carboxylate anions strongly chelating metal cations like Ca{sup 2+} and forming strong macromolecular crosslinks which contribute in large measure to network polymer structure. Removal of the carboxylic groups at ambient temperature by anaerobic organisms would unravel the macromoleculer network, resulting in smaller coal macromolecules with increased H/C ratio which has better fuel value and better processing prospects. These studies described here sought to find biological methods to remove carboxylic functionalities from low rank coals under ambient conditions and to assess the properties of these modified coals towards coal liquefaction. Efforts were made to establish anaerobic microbial consortia having decarboxylating ability, decarboxylate coal with the adapted microbial consortia, isolate the organisms, and characterize the biotreated coal products. Production of CO{sup 2} was used as the primary indicator for possible coal decarboxylation.
Date: August 5, 1993
Creator: Jain, M. K. & Narayan, R.
Object Type: Report
System: The UNT Digital Library
Generalized perturbation method expansions of the total energy of an alloy (open access)

Generalized perturbation method expansions of the total energy of an alloy

The generalized perturbation method, commonly used in connection with the band energy contribution to the energy of a solid to approximate the total energy of an ordered configuration of an alloy, is reformulated with respect to total energy. The connection of the results derived here to those obtained based on the band energy is pointed out, and possible applications of the method is discussed.
Date: August 5, 1993
Creator: Gonis, A.; Singh, P. P. & Turchi, P. E. A.
Object Type: Article
System: The UNT Digital Library
Imaging of surface structure with energy-dependent photoelectron diffraction (open access)

Imaging of surface structure with energy-dependent photoelectron diffraction

Energy-dependent photoelectron diffraction (EDPD) has been used to determine the surface structure of a surface alloy. Direct imaging has been achieved by Fourier transformation of experimental energy-dependent photoelectron diffraction data. This holographic method, based upon the intersection of contour arcs associated with each measurement direction, can provide vectorial atomic positions with atomic resolution. Experimental analysis is supported by Fourier transformation of simulations from multiple scattering calculations. The surface geometry of c(2x2) Au/Cu(001) has been imaged in an elementally-specific manner, with clear, non-model-dependent discrimination of the surface alloy over the overlayer structure.
Date: August 5, 1993
Creator: Tobin, J. G.; Waddill, G. D.; Li, Hua & Tong, S. Y.
Object Type: Article
System: The UNT Digital Library
Lattice Information Service for the RHIC Project (open access)

Lattice Information Service for the RHIC Project

None
Date: August 5, 1993
Creator: C., Saltmarsh; Satogata, T. & Peggs, S.
Object Type: Report
System: The UNT Digital Library
Overview of crash and impact analysis at Lawrence Livermore National Laboratory (open access)

Overview of crash and impact analysis at Lawrence Livermore National Laboratory

This work provides a brief overview of past and ongoing efforts at Lawrence Livermore National Laboratory (LLNL) in the area of finite-element modeling of crash and impact problems. The process has been one of evolution in several respects. One aspect of the evolution has been the continual upgrading and refinement of the DYNA, NIKE, and TOPAZ family of finite-element codes. The major missions of these codes involve problems where the dominant factors are high-rate dynamics, quasi-statics, and heat transfer, respectively. However, analysis of a total event, whether it be a shipping container drop or an automobile/barrier collision, may require use or coupling or two or more of these codes. Along with refinements in speed, contact capability, and element technology, material model complexity continues to evolve as more detail is demanded from the analyses. A more recent evolution has involved the mix of problems addressed at LLNL and the direction of the technology thrusts. A pronounced increase in collaborative efforts with the civilian and private sector has resulted in a mix of complex problems involving synergism between weapons applications (shipping container, earth penetrator, missile carrier, ship hull damage) and a more broad base of problems such as vehicle impacts as discussed …
Date: August 5, 1993
Creator: Logan, R. W. & Tokarz, F. J.
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: LO93-060 (open access)

Texas Attorney General Opinion: LO93-060

Letter opinion issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether the College of the Mainland of is required to pay an impact fee assessed by the Galveston Drainage District No. 2 under chapter 395 of the Local Government Code (ID# 19756)
Date: August 5, 1993
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Pecan Pest Management Newsletter, Volume 93, Number 7, August 1993 (open access)

Texas Pecan Pest Management Newsletter, Volume 93, Number 7, August 1993

Newsletter focusing on pecan disease and pest control in Texas, including prevention, identification, treatment, and educational opportunities.
Date: August 5, 1993
Creator: Texas Agricultural Extension Service
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
The Trade and Development Agency (open access)

The Trade and Development Agency

Congressional interest linking foreign aid more directly with commercial interests has grown in recent years as the U.S. budget becomes increasingly strained, constituent support for foreign aid dwindles, and U.S. industries seek Federal assistance. The Trade and Development Agency is one of several Government agencies involved in "aid for trade"--programs that combine development assistance and export promotion.
Date: August 5, 1993
Creator: Epstein, Susan B.
Object Type: Report
System: The UNT Digital Library
Ceramic films and interfaces: Chemical and mechanical properties. Final report (open access)

Ceramic films and interfaces: Chemical and mechanical properties. Final report

Results are reported in two areas: (1) understanding the mechanism of superplasticity in those that show unusual resistance to intergranular cavitation, and (2) understanding the growth of heteroepitaxial films of oxides by CVD (NiO, TiO{sub 2}).
Date: June 5, 1993
Creator: Raj, R.
Object Type: Report
System: The UNT Digital Library
First principles theory of disordered alloys and alloy phase stability (open access)

First principles theory of disordered alloys and alloy phase stability

These lecture notes review the LDA-KKR-CPA method for treating the electronic structure and energetics of random alloys and the MF-CF and GPM theories of ordering and phase stability built on the LDA- KKR-CPA description of the disordered phase. Section 2 lays out the basic LDA-KKR-CPA theory of random alloys and some applications. Section 3 reviews the progress made in understanding specific ordering phenomena in binary solid solutions base on the MF-CF and GPM theories of ordering and phase stability. Examples are Fermi surface nesting, band filling, off diagonal randomness, charge transfer, size difference or local strain fluctuations, magnetic effects; in each case, an attempt is made to link the ordering and the underlying electronic structure of the disordered phase. Section 4 reviews calculations of electronic structure of {beta}-phase Ni{sub c}Al{sub 1-c} alloys using a version of the LDA-KKR-CPA codes generalized to complex lattices.
Date: June 5, 1993
Creator: Stocks, G. M.; Nicholson, D. M. C. & Shelton, W. A.
Object Type: Article
System: The UNT Digital Library
Distinguishing Gyro-Bohm and Bohm scaling in stellarators (open access)

Distinguishing Gyro-Bohm and Bohm scaling in stellarators

With statistical analysis of global data from one, two and four stellarators, it is possible to draw limited conclusions whether Gyro- Bohm or Bohm scaling prevails. Either scaling may be favored, depending on whether corrections are included for possible {Beta} and v{sub *} corrections and whether all data are taken, or selected cases with low collisionality, or low net toroidal current, or with ECH heating applied, and so on. Monte Carlo-like simulations are used to test reliability of inferences about power-law scaling exponents made from data having substantial statistical variance and collinearity of control parameters. These show that for reliable conclusions, statistical studies should be augmented; more directed experimental studies are needed, with well controlled discharges and radially resolved data - such as those already begun on ATF and W7-AS.
Date: May 5, 1993
Creator: Dory, R.A.; Murakami, M. & Stroth, U.
Object Type: Article
System: The UNT Digital Library
Human Factors evaluation of LCS 254 and 255 (open access)

Human Factors evaluation of LCS 254 and 255

This report includes the results of the Human Factors evaluation of the local control stations (LCS) 254 and 255 performed by Savannah River Technology Center (SRTC) Human Factors. Recommendations are included in order that the panel designs will be upgraded to comply with human engineering design guidelines. Figures 1 and 2 are included as examples of recommended changes. Also, consideration was given to including the proposed engineering changes which are currently on-going for LCS 255. Appendix A identifies the human engineering requirements from NUREG-0700 which were used in the evaluation process, and the areas of the design which do not comply with the guidelines. Those areas of the panel design which fail to comply with the human engineering guidelines are label location, label content, location aids, panel layout, and control display integration. Each of these design deficiencies and proposed corrections are described in this report.
Date: May 5, 1993
Creator: Goffe, L. & Held, J. E.
Object Type: Report
System: The UNT Digital Library
Japan's Foreign Aid (open access)

Japan's Foreign Aid

Japan has quickly risen to prominence as a donor of official development assistance (ODA), providing volumes of aid on par with the United States since the late 1980s. Originally a tool to bolster Japan's postwar economic recovery, Japanese aid has gradually assumed importance as a foreign policy tool. Faced with increased pressure from the international community to play a greater role in meeting global challenges and lacking the military and diplomatic resources of other nations, Japan has increasingly turned to its foreign aid as a source of world influence.
Date: May 5, 1993
Creator: Hankes, Nancy J
Object Type: Report
System: The UNT Digital Library
Measurement of source tube radial position in cast EMC testbeam module (open access)

Measurement of source tube radial position in cast EMC testbeam module

Using a {sup 137}Cs source we have determined the position of two of the source tubes embedded in the Pb absorber in the cast EMC module used in the Fermilab test beam. Two scintillator tiles placed in the gaps on both sides of an absorber containing a source tube were readout into independent phototubes. The difference in scintillator response was measured in two towers at two different source tube layers. We find the source tube to be displaced towards the (radial) front of the EMC by about 1.6 mm in both measurements. Work is proceeding now to check other source tubes in other locations.
Date: May 5, 1993
Creator: Jankowski, D. J. & Stanek, R.
Object Type: Report
System: The UNT Digital Library
New techniques in 3D scalar and vector field visualization (open access)

New techniques in 3D scalar and vector field visualization

At Lawrence Livermore National Laboratory (LLNL) we have recently developed several techniques for volume visualization of scalar and vector fields, all of which use back-to-front compositing. The first renders volume density clouds by compositing polyhedral volume cells or their faces. The second is a ``splatting`` scheme which composites textures used to reconstruct the scalar or vector fields. One version calculates the necessary texture values in software, and another takes advantage of hardware texture mapping. The next technique renders contour surface polygons using semi-transparent textures, which adjust appropriately when the surfaces deform in a flow, or change topology. The final one renders the ``flow volume`` of smoke or dye tracer swept out by a fluid flowing through a small generating polygon. All of these techniques are applied to a climate model data set, to visualize cloud density and wind velocity.
Date: May 5, 1993
Creator: Max, N.; Crawfis, R. & Becker, B.
Object Type: Article
System: The UNT Digital Library
Radiative divertor modeling studies (open access)

Radiative divertor modeling studies

A two-dimensional fluid code called UEDGE is used to simulate the edge plasma in tokamak divertors and to evaluate methods for reducing the heat load on divertor plates by radiating some of the power before it reaches the plates. UEDGE is a fully-implicit code being developed jointly by us, D. A. Knoll and R. B. Campbell. For these studies, UEDGE uses a banded matrix solver and a fixed-fraction impurity model. Work is presently underway with Knoll and Campbell to include a memory-efficient iterative solver and a model of impurity transport. Simulations of the proposed TPX device show that a few percent nitrogen concentration in the scrape-off layer can radiate up to 80% of the divertor power, thus reducing the peak heat flux and electron temperature at the divertor plate to acceptable values. A comparison of the neutral gas distribution from UEDGE with results from the DEGAS Monte Carlo neutrals code confirms the validity of our fluid neutrals model.
Date: May 5, 1993
Creator: Rensink, M. E.; Allen, S. L.; Hill, D. N.; Kaiser, T. B. & Rognlien, T. D.
Object Type: Article
System: The UNT Digital Library
Recent developments on ECR sources at LBL (open access)

Recent developments on ECR sources at LBL

After a number of refinements, the stability and ease of tuning of the LBL AECR ion source are greatly improved. Several nuclear science experiments have now used cyclotron ion beams injected by the AECR ion source and have taken advantage of its good short and long term-stability and high performance. Refinements include installation of a dc filament power supply for the electron gun, improved gas flow control.and temperature stabilization of parts of the microwave transmission network. Measurements of the mean plasma potential and plasma potential difference were made on the AECR and the LBL ECR sources. The absolute. mean potentials of plasmas of oxygen, argon, and argon mixed with oxygen in the AECR have been determined. These plasma potentials are positive with respect to the plasma wall and are on the order of a few tens of volts for microwave power up to 600 W and normal operating gas flow. Electrons injected by an electron gun into the AECR plasma reduce the plasma potentials. Beam energy spreads of oxygen, argon and argon mixed with oxygen have also been measured. Measurement of the plasma potential difference between the first and the second stage of the LBL ECR ion source shows that …
Date: May 5, 1993
Creator: Xie, Z. Q. & Lyneis, C. M.
Object Type: Article
System: The UNT Digital Library