This document recommends an interim dilution strategy for the low nitrite precipitate hydrolysis process. A minimum carbon dioxide purge rate of 27 scan during feeding and for 15 minutes after feeding and a maximum precipitate slurry feed rate of 36 gpm are recommended. These recommendations provide an interim dilution strategy that will provide for the start of cold chemical runs and until additional offgas data is collected from the PHEF (Precipitate Hydrolysis Experimental Facility).

Melter feed preparation processes, incorporating a final wash of the precipitate slurry feed to Defense Waste Processing Facility (DWPF) and a partial substitution of the SRAT formic acid requirement with nitric acid, should not produce peak hydrogen generation rates during Cold Chemical Runs (CCR`s) and radioactive operation greater than their current, respective hydrogen design bases of 0.024 lb/hr and 1.5 lb/hr. A single SRAT bench-scale process simulation for CCR-s produced a DWPF equivalent peak hydrogen generation rate of 0.004 lb/hr. During radioactive operation, the peak hydrogen generation rate will be dependent on the extent DWPF deviates from the nominal precipitate hydrolysis and melter feed preparation process operating parameters. Two actual radioactive sludges were treated according to the new flowsheets. The peak hydrogen evolution rates were equivalent to 0.038 and 0.20 lb/hr (DWPF scale) respectively. Compared to the formic acid -- HAN hydrolysis flowsheets, these peak rates were reduced by a factor of 2.5 and 3.4 for Tank 15 and Tank 11 sludges, respectively.

Objective is to develop producing active, stable iron Fischer-Tropsch catalysts for use in slurry-phase synthesis reactors and to synthesize such catalysts on a large scale for process development and long-term testing in slurry bubble-column reactors. A mixed oxalate of Fe, Cu, and K was prepared; a catalyst will be prepared from this material. An evaluation run was performed on an Fe-based UCI catalyst, which was shown to produce low levels of C{sub 1} and C{sub 2} paraffins; e.g., at the end of the run, when the catalyst was converting 60% of the CO, the C{sub 1} and C{sub 2} paraffin selectivities were 4.2 and 1.0, respectively.

The project objectives are (1) to explore new silylation reagents and reaction conditions with the purpose of reducing the thickness and increasing the permeance of silica membranes, (2) to delineate mechanism and kinetics of silica deposition, (3) to measure the permeability of silica layers at different extents of deposition and (4) to mathematically model the relationship of permeability and membrane structure. Study of the literature has suggested the use of certain ultrafast silylation reagents for the purpose of achieving thinner deposit layers and, hence, increase membrane permeance. The silylation reagents available commercially are suitable for grafting only one molecule per silanol ({minus}OH) group on the solid surface. The silylation reagents needed for our purposes must contain hydrolyzable groups such that the {minus}OH groups can be regenerated and the reaction continued to build a multilayer deposit. During the reporting period we have started to explore the synthesis of silylation reagents suitable for multilayer formation. A systematic series of kinetic experiments were carried out using a thermogravimetric analysis system (TGA) to measure the reaction rate of SiCl{sub 4} with surface {minus}OH groups, the rate of H{sub 2}O with surface chloride groups and the rates of condensation reactions between two {minus}OH groups and …

The present DWPF flowsheet calls for the chemical treatment of waste sludge with 90 wt % formic acid prior to the addition of the Precipitate Hydrolysis Aqueous (PHA) product. An alternative processing methodology, denoted the ``Nitric Acid Flowsheet``, has been proposed. in the application of this flowsheet, nitric acid would be used to neutralize sludge base components (hydroxides and carbonates) prior to the addition of late wash PHA. The late wash PHA will contain sufficient quantities of formic acid to adequately complete necessary reduction-oxidation (REDOX) reactions.

This report describes the work done by Science Applications International Corporation to study the effects of energetic particles on the microstability of a high temperature tokamak. The effects of an energetic population on ballooning modes in a large aspect ratio, shifted circular flux surface tokamak equilibrium are investigated with the newly developed gryokinetic numerical technique. The gryokinetic equations for the background ion and electron, as well as that of the energetic population are solved directly as an initial problem. The energetic particles are modeled with a slow-down distribution in energy. It is found that the ballooning mode stability of the plasma with an energetic species of increasing concentration does not differ much from an increase in the background plasma beta, except for possible energetic particle drift resonances. This result is encouraging to the idea that energetic particles such as alphas may be used to stabilize the ballooning modes in a fusion reactor.

Large eddy simulation, LES, has often been carried out for the idealized situation of a simple convective boundary layer. Studies of dual Doppler radar and aircraft data from the Phoenix II experiment indicate that the boundary layer of the Colorado High Plains is not a purely convective boundary layer and it is influenced by the mountains to the west. The purpose of this study is to investigate the atmospheric boundary layer on one particular day on the Colorado High Plains. This research applies a LES nested within larger grids, which contain realistic topography and can simulate the larger-scale circulations initiated by the presence of the mountain barrier. How and to what extent the atmospheric boundary layer of the Colorado High Plains is influenced by larger scale circulations and other phenomena associated with the mountain barrier to the west is investigated. The nested grid LES reproduces the characteristics of the atmosphere for the case study day reasonably well. The mountains influence the atmospheric boundary layer over the plains to the east in several ways. The mountains contribute to the vertical shear of the horizontal winds through the thermally-induced mountain-plains circulation. As a consequence of the wind shear, the boundary layer that …

Plastic crystal behavior is observed in semiconducting CsPb and NaSn at high temperature (600 and 500 C, respectively). This behavior is associated with M{sub 4}{sup 4{minus}} or A{sub 4}M{sub 4} structural units orientationally disordering about 50 C below the melting point where translational disorder sets in. This orientational disorder is different in the two phases, exhibiting jump reorientations in CsPb and a more isotropic behavior in NaSn. In other Zintl compounds such as KPb, there is a single melting point where orientational and translational disorder sets in simultaneously; the classification of the different Zintl compounds into these two different kinds of behavior will require calorimetry or neutron diffraction below the melting point. (DLC)

Interagency panels evaluating nuclear thermal propulsion (NTP) development options have consistently recognized the need for constructing a major new ground test facility to support fuel element and engine testing. This paper summarizes the requirements, configuration, and baseline performance of some of the major subsystems designed to support a proposed ground test complex for evaluating nuclear thermal propulsion fuel elements and engines being developed for the Space Nuclear Thermal Propulsion (SNTP) program. Some preliminary results of evaluating this facility for use in testing other NTP concepts are also summarized.

A network of hf ionospheric sounders consisting of two transmitter and two receiver stations was deployed to detect the effects of acoustic waves generated by surface ground motion following an underground nuclear test (UGT) at the Nevada Test Site. The frequency of the transmissions were chosen so that the hf radio waves were totally reflected in the E layer of the ionosphere at an altitude of approximately 100 km. The transmissions were highly stable cw tones at two frequencies separated by 100 kHz so that two altitudes separated by approximately .5 km could be sensed. The network sampled four geographic locations in the ionosphere ranging from almost directly overhead of the UGT out to a horizontal range of 60 km. The ionospheric sounders detected disturbances on all the paths beginning at approximately 325 s after the UGT which persisted for up to 100 s. These disturbances will be described in detail in a later paper. Shortly after the UGT an extended series of ionospheric disturbances were detected which we ascribe to the arrival of acoustic shock waves at the E layer caused by the surface detonation of ordinance with effective yields of 450 kg of high explosive during an unrelated …

The primary objective of the study is to develop a computer model for a base line direct coal liquefaction design based on two stage direct coupled catalytic reactors. This primary objective is to be accomplished by completing the following: a base line design based on previous DOE/PETC results from Wilsonville pilot plant and other engineering evaluations; a cost estimate and economic analysis; a computer model incorporating the above two steps over a wide range of capacities and selected process alternatives; a comprehensive training program for DOE/PETC Staff to understand and use the computer model; a thorough documentation of all underlying assumptions for baseline economics; and a user manual and training material which will facilitate updating of the model in the future.

This report discusses whether the events that occur in the universe evolve deterministicly or randomly or both. (LSP).

This report focuses on the design and fabrication of high spectral resolution FTIR (Fourier Transform Infrared) instrumentation for the CART sites of the Atmospheric Radiation Measurement (ARM) Program. The ultimate objective of this grant is to develop three different types of instruments, named the AERI, AERI-X, and SORT. The Atmospheric Emitted Radiance Interferometer (AERI) is the simplest. It will be available for early deployment at the first ARM site and will be deployable at several locations in the extended network to give horizontal coverage. The AERI will be an 0.5 cm{sup {minus}1} resolution instrument, which measures accurately calibrated radiance spectra for radiation studies and for remote sensing of atmospheric state variables. The AERI-X and the SORTI are higher spectral resolution instruments for obtaining the highest practical resolution for spectroscopy at the ARM central sites. The AERI-X, like the AERI will measure atmospheric emitted radiance, but with resolutions as high as 0.1 cm{sup {minus}1}. The Solar Radiance Transmission Interferometer will measure the total transmission of the atmosphere by tracking the sun through changes in atmospheric air mass. The large solar signal makes it practical for this instrument to offer the ultimate in spectral resolution, about 0.002 cm{sup {minus}1}.

We present the results of a measurement to understand the effects of transverse misplacement of the {sup 137}Cs source tube inside the cast Pb plates of the SDC EMC calorimeter. The PMT current from a scintillator was measured as the {sup 137}Cs source was displaced by varying thicknesses of Pb, as well as varying thicknesses of air gap. At a nominal depth of 2 mm in Pb, we find a change in scintillator output of about 25%/mm, and about 10%/mm of air gap. The data are compared to a simple calculation. By taking the sum of the scintillators on top and below a source tube, we estimate a source tube displacement of {plus_minus}450{mu} will cause an error in the PMT output by 1%.

List of the Effective Screening Levels used by the Texas Air Control Board to examine air pollution in 1992.

An investigation aimed at devising a procedure for preparing alkyl-or aryl-capped iron sulfide particles continues. An initial attempt to prepare fine-particle, aryl-capped iron sulfides (S-31) involved the competitive reaction of thiophenol (PhSH) and sodium sulfide (Na{sub 2}S) with Fe(II). However, SEM examination of the particles formed by this procedure indicated that no size control had been attained. It was thought that the phenyl group of thiophenol was not bulky enough to prevent thiolate bridging and consequent particle size growth of the metal sulfide. So the bulkier thiol 1-adamantanethiol was synthesized and used in synthesis S-33 in the next attempt to prepare fine-particle, capped iron sulfides.

An investigation aimed at devising a procedure for preparing alkyl-or aryl-capped iron sulfide particles continues. An initial attempt to prepare fine-particle, aryl-capped iron sulfides (S-31) involved the competitive reaction of thiophenol (PhSH) and sodium sulfide (Na{sub 2}S) with Fe(II). However, SEM examination of the particles formed by this procedure indicated that no size control had been attained. It was thought that the phenyl group of thiophenol was not bulky enough to prevent thiolate bridging and consequent particle size growth of the metal sulfide. So the bulkier thiol 1-adamantanethiol was synthesized and used in synthesis S-33 in the next attempt to prepare fine-particle, capped iron sulfides.

Weekly newsletter discussing natural resources, parks, hunting and fishing, and other information related to the outdoors in Texas.

The authors propose an all-scintillating fiber detector for the purpose of outer tracking for the SDC. The objectives of this tracking system are to: (1) provide a first level trigger for {vert_bar}{eta}{vert_bar} < 2.3 with sharp p{sub T} threshold with the ability to resolve individual beam crossings; (2) provide pattern recognition capability and momentum resolution which complements and extends the capabilities of the inner silicon tracking system; (3) provide three dimensional linkage with outer detection systems including the shower maximum detector, muon detectors, and calorimetry; (4) provide robust tracking and track-triggering at the highest luminosities expected at the SSC. The many attractive features of a fiber tracker include good position resolution, low occupancy, low mass in the active volume, and excellent resistance to radiation damage. An additional important feature, especially at the SSC, is the intrinsically prompt response time of a scintillating fiber. This property is exploited in the construction of a level 1 trigger sensitive to individual beam crossings.

Conducting polymers (CPs) have attracted attention as potentially useful materials for electrochemical capacitors due to their high energy storage capacity and their comparatively low cost. During the course of this research the authors explored a number of poly(heteroaromatic) systems, in conjunction with several nonaqueous electrolytes, that could be used as active materials in electrochemical capacitors. They identified a new configuration for such capacitors based on p- and n-dopable polymers and prepared a number4r of such materials. A new electrolyte, TMATFMS, which facilitates n-doping in these polymers was also synthesized and tested. A patent disclosure on these discoveries has been filed with Mr. Ray Wilson of LANL.

Two radio frequency (RF) cavities are needed in the Positron Accumulator Ring (PAR) of the Advanced Photon Source. One is for the first harmonic frequency at 9.8 MHz, and the other is for the twelfth harmonic frequency at 118 MHz. This note reports on the design of the 118 MHz RF cavity. Computer models are used to find the mode frequencies, impedances, Q-factors, and field distributions in the cavity. The computer codes MAFIA, URMEL, and URMEL-T are useful tools which model and simulate the resonance characteristics of a cavity. These codes employ the finite difference method to solve Maxwell`s equations. MAFIA is a three-dimensional problem solver and uses square patches to approximate the inner surface of a cavity. URMEL and URMEL-T are two-dimensional problem solvers and use rectangular and triangular meshes, respectively. URMEL-T and MAFIA can handle problems with arbitrary dielectric materials located inside the boundary. The cavity employs a circularly cylindrical ceramic window to limit the vacuum to the beam pipe. The ceramic window used in the modeling will have a wall thickness of 0.9 cm. This wall thickness is not negligible in determining the resonant frequencies of the cavity. In the following, results of two- and three-dimensional modeling …

Shocks form in finite time in systems of quasilinear hyperbolic equations in one space variable which are genuinely nonlinear. The authors write down a simple geometric construction for systems of two equations, and use it to obtain a priori estimates for the growth of the derivatives. They also find realistic bounds on the maximum and minimum time of existence of smooth solutions for large amplitude waves in a model system of an unusual type.

Annual report about the overall condition of the East Central Independent School District in San Antonio, providing statistics and assessments for the 1990-1991 school year.

Newsletter of the Texas Bureau of Disease Control and Epidemiology discussing the news, activities, and events of the organization and other information related to health in Texas.