A removable and reusable filter attachment system is disclosed. A filter medium is fixed to, and surrounded by, a filter frame having a coaxial, longitudinally extending, annular rim. The rim engages an annular groove which surrounds the opening of a filter housing. The annular groove contains a fusible material and a heating mechanism for melting the fusible material. Upon resolidifying, the fusible material forms a hermetic bond with the rim and groove. Remelting allows detachment and replacement of the filter frame.

A coaxial high voltage, high current switch having a solid cylindrical cold cathode coaxially surrounded by a thin hollow cylindrical inner electrode and a larger hollow cylindrical outer electrode is described. A high voltage trigger between the cathode and the inner electrode causes electrons to be emitted from the cathode and flow to the inner electrode preferably through a vacuum. Some of the electrons penetrate the inner electrode and cause a volumetric discharge in the gas (which may be merely air) between the inner and outer electrodes. The discharge provides a low impedance path between a high voltage charge placed on the outer electrode and a load (which may be a high power laser) coupled to the inner electrode. For high repetition rate the gas between the inner and outer electrodes may be continuously exchanged or refreshed under pressure.

Methods of removing fluorides from water are reviewed and recommendations are made for treating geothermal water used by the Boise Geothermal Project, Boise, Idaho. The Boise geothermal water except for its high fluoride content would be high quality, suitable for primary drinking water. Fluoride ranges from about 15 to 25 mg/l in water from various wells in the Boise region where the Project plans to obtain hot water. Four techniques for removing fluorides from water have been studied extensively during the past 15 years or so. Electrodialysis and reverse osmosis are useful in reducing total dissolved solids from brackish water, but are nonspecific and are too expensive for treatment of the Boise geothermal water. Selective precipitation is a widely used technique for treating water, but would also prove expensive for the Boise geothermal water because of the relatively high solubility of fluoride salts and consequently high concentration (and cost) of precipitants required to reduce the fluorides to an acceptable level. Ion-exchange separation using activated alumina as the exchange medium appears to be the most promising technique and we recommend that some laboratory and pilot studies be conducted to establish suitability and operating boundaries.

An improved downhole steam injector has an angled water orifice to swirl the water through the device for improved heat transfer before it is converted to steam. The injector also has a sloped diameter reduction in the steam chamber to throw water that collects along the side of the chamber during slant drilling into the flame for conversion to steam. In addition, the output of the flame chamber is beveled to reduce hot spots and increase efficiency, and the fuel-oxidant inputs are arranged to minimize coking.

Several practical aspects of rf acceleration (by a MEQALAC accelerator, for example) of positive and negative ions for MFE neutral injection were considered. The beam transport, gas flow, differential pumping, and compatibility with MFE beam lines were examined. It was found that rf acceleration has several advantages over dc acceleration, especially if high energy (over 100 keV) and/or high purity (over 99%) is required. Therefore rf acceleration should be considered especially in connection with negative ions, which also have competitive advantages under such requirements. Beam densities for rf may be lower than dc beam densities because of space charge limitations and electrode transparency. However, the overall dimensions of an rf system are competitive with or smaller than the dimensions of a dc system of equal current and voltage because the gas pumping and electrical insulation are included within the rf electrode assembly. Ion source development is required to produce an array of many small beams suitable for injection into a MEQALAC.

The present invention is directed to a fuel-air control system for a combustor in which coal-derived gas of varying heat content is used. To maintain the temperature in the combustor at an essentially constant value the fuel-to-air ratio is adjusted by using a temperature actuated variable pressure regulator in the gas feed line to compensate for the variability of the heat content of the gas. The velocity of the products of combustion is maintained at an essentially constant flow rate by controlling the mass flow of the air and fuel through linked valves on the gas and air feed lines.

Rutherford scattering of neutral particles by plasma ions is examined as a method for determining plasma ion in the central cell fo the Tandem Mirror Experiment (TMX). When a scattering configuration, consisting of a 20-keV-, 10-A-deuterium neutral beam and an energy analyzer with a 1% resolution, is arranged such that only neutral particles scattered by plasma ions over an angle of 10/sup 0/ are accepted, central-cell ion temperatures in the 30- to 1000-eV range can be measured. The count rate registered by the detector(s) is estimated to be 2000 counts/ms. Consequently, good statistical accuracy and time resolution are attainable simultaneously. The results of the calculation are presented such that the scaling of the count rates and the energy broadening with scattering angle, neutral-beam energy, ion temperature, and plasma density can easily be deduced. Neutral helium beams are also considered; they have some advantages over deuterium beams. The background signal, caused by neutral particles entering the detector after two successive charge-exchange collisions, is examined and ways to completely eliminate this background are indicated.

A breeding ratio of at least 1.2 was a design goal for CRBRP. The value for the initial core (using plutonium with 11% /sup 240/Pu) calculated with ENDF/B-IV data is 1.27. Engineering mock-up studies for CRBRP were made in ZPPR-11. Analysis of ZPPR-11 using ENDF/B-IV data showed consistent underprediction of K/sub eff/ by about 1.5% and overpredictions of the /sup 238/U capture to /sup 239/Pu fission ratio (C8/F9) between 5% and 8%. These results are typical for all LMFBR critical assemblies at ANL. The following approach was used to determine the breeding ratio: sensitivity analysis of a range of fast reactor benchmarks and a fit to the experimental data by data adjustment; tests of the adjusted data against experiments in ZPPR-11; calculations for CRBRP with ENDF/B-IV data and the adjusted data to predict the breeding ratio bias; and estimates of k/sub eff/ and breeding ratio uncertainties using data sensitivities for CRBRP.

Newsletter of the Texas Air Control Board including information about the Board as well as news, events, and other relevant information related to air quality in Texas.

This paper discusses the use of a free-electron laser amplifier as a means of converting the kinetic energy of an electron beam into coherent radiation. In particular, the use of an induction linear accelerator is discussed. The motion of the elections in the tapered and untapered wiggler magnets is discussed as well as the beam emittance, and the radiation fields involved. (LSP)

This paper describes a fast rise, low-impedance pulse generator that has been developed at the Lawrence Livermore National Laboratory. The design specifications of this generator are: 50-kV operating voltage, 1-ohm output impedance, subnanosecond rise time, and a 2 to 10 nanosecond pulse length. High repetition rate is not required. The design chosen is a parallel-plate, folded Blumlein generator. A tack switch is utilized for its simple construction and high performance. The primary diagnostic is a capacitive voltage divider with a B probe used to measure the current waveform.

The TMX-U data system is a general-purpose system for acquiring, analyzing, and output of TMX-U data, and can also apply to any pulsed controlled thermonuclear experiment. In its present implementation, it routinely acquires 3 Mbytes of data per shot at an average rate of one shot every 8 minutes. For increased throughput, the system uses 5 CPUs accessing shared disk memory with a capacity of about 500 Mbytes. All acquisition, analysis, and output of data is handled by a collection of standard program modules (processors), which can be linked together to form chained calculations. Processing for various shots may be allowed to overlap, with higher priority results being available quickly, while lower priority results being allowed to lag behind and catch up in natural lulls in the experiment. Selection of tasks (processor invokations) is done independently by each of the 5 CPUs in the system, and each task can run in any suitable CPU.

Mathematical models and numerical methods for a two-dimensional porous body simulation of steady state and transient thermal-hydraulics conditions in LMFBR subassemblies resulting in the TWIST computer code are presented. Comparison of calculated results to steady state and transient out-of-pile sodium experiments show good agreement for cross-assembly temperature distributions for a wide range of heat transfer and flow conditions.

The current situation concerning supernova simulations and the theory of neutron star structure are studied with respect to what they tell about the equation of state. A new mechanism that could help power supernovae is suggested.

Sensitivity analysis of practical problems can be performed systematically and very efficiently by using adjoint functions. In areas of interest to nuclear reactors, this efficiency has been amply demonstrated on several widely used codes for neutronics and/or thermal hydraulic calculations. Applications of the adjoint method of sensitivity analysis to models involving phase transitions, where non-differentiability occurs, do not seem to have been reported to date. The purpose of this paper is to report results from a successful adjoint sensitivity analysis of a space- and time-dependent system where phase transition occurs due to boiling. The specific model chosen for this analysis is a simplified but representative model of a BWR pump-trip-type accident. This model is of particular importance to BWR safety, since pump failure is one of the most limiting hypothetical accidents in BWR's. This model simulates an exponential flow decay of initially subcooled FREON-114 flowing through a heated channel and undergoing boiling transition.

EPIC is a fluid/envelope type computer code designed to study the energetics and dynamics of a high energy, high current electron beam passing through a gas. The code is essentially two dimensional (x, r, t) and assumes an axisymmetric beam whose r.m.s. radius is governed by an envelope model. Electromagnetic fields, background gas chemistry, and gas hydrodynamics (density channel evolution) are all calculated self-consistently as functions of r, x, and t. The code is a collection of five major subroutines, each of which is described in some detail in this report.

As a part of an ongoing, EPRI-sponsored project whose aim is the quantification and reduction of fluence uncertainties in the pressure vessel of operating PWR's, this work describes the calculation of sensitivities necessary for the propagation of PWR core source distribution uncertainties to the flux spectrum at locations of interest (e.g., the cavity or T/4 pressure vessel locations) in the AN0l reactor. In this case standard perturbation theory requires an adjoint run to be made for each group flux since each group flux is a response. An alternate approach has been developed by Cacuci which should be more efficient than the standard approach although it has not yet been applied to a flux spectrum response.

We have designed, built, and characterized uv preilluminated gas switches for a trigger circuit and a low inductance discharge circuit. These switches have been incorporated into a 54 x 76 x 150 cm pulser module to produce a 1 Ma output current rising at 5 x 10/sup 12/ amps/sec with 1 ns jitter. Twenty such modules will be used on the Nova Inertial Confinement Fusion Laser System for plasma retropulse shutters.

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.

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.

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.

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, Jim Mattox, regarding a legal question submitted for clarification; Authority of the deputy commissioner of agriculture to sit in the commissioner's absence as a voting member of the Texas Agricultural Finance Authority.

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, Jim Mattox, regarding a legal question submitted for clarification; Whether board members of a metropolitan authority created pursuant to V.A.T.C. article 1118x may be appointed for four year terms pursuant to section 6B(e) of the article in light of Texas Constitution restrictions on the lengths of terms for public offices.

Document 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, Jim Mattox, regarding a legal question submitted for clarification; Conflict between provisions of the Parks and Wildlife Code (RQ-1351)