The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of related diffraction, imaging and spectroscopic methods, it is now possible to obtain structural and chemical information from the same region of the sample at high spatial resolution. In this review, recent advances along with representative examples in the application of high resolution electron microscopy (HREM), convergent beam electron diffraction (CBED), low atomic number element microanalysis by x-ray emission spectroscopy (XES), fine structures in electron energy-loss spectroscopy (EELS) and specific site occupancy determination by channeling experiments are discussed.

Modeling assessments of the atmospheric chemistry, air quality and climatic conditions of the past, present and future require as input inventories of emissions of the appropriate chemical species constructed on appropriate spatial and temporal scales. The task of the Global Emissions Inventories Activity (GEIA) of the International Global Atmospheric Chemistry Project (IGAC) is the production of global inventories suitable for a range of research applications. Current GEIA programs are generally based on addressing emissions by species; these include CO{sub 2}, NH{sub 3}/N{sub 2}O, SO{sub 2}/NO{sub x}, CFC, volatile organic compounds and radioisotopes. In addition a separate program to inventory emissions from biomass burning is also being structured, plus an additional program to address data management issues for all the developing inventories. Program priorities are based on current knowledge and tasks needed to produce the desired inventories. This paper will discuss the different types of global inventories to be developed by the GEIA programs, their key characteristics, and areas to be addressed in the compilation of such inventories. Results of the first GEIA task, a survey of existing inventories and auxiliary data, will be presented. The survey included status assessments for the available inventory information for nineteen different atmospheric species or …

Condensing economizers can be used to increase the thermal efficiency of boilers and furnaces. This project has involved a study of these specifically for application to coal-water mixture fuels although the results can be extended to other fuels. experimental studies to evaluate thermal performance and removal of particulates across indirect contract economizers have been performed. The test arrangement incorporates oil firing with the injection of flyash into the flue gas to simulate coal combustion products. Water sprays into the combustion products are used to achieve variable flue gas moisture content and a variable amount of condensation in the economizers. The economizers are tubular with flue gas on the outside of the tubes. Tube surfaces are plastic coated to prevent corrosion. The gas temperature and condensation profiles through the economizers have been predicted and overall predicted performance has been compared with test results. Mechanisms for particle removal are discussed and predicted removal efficiencies as a functions of particle diameter are presented. It is is shown that inertial impaction is the dominant mechanism and particle removal efficiencies up to 89% have been realized.

We present new results in axiomatic group theory obtained by using automated deduction programs. The results include single axioms, some with the identity and others without, for groups of exponents 3, 4, 5 and 7, and a general form for single axioms for groups of odd exponent. The results were obtained by using the programs in three separate ways: as a symbolic calculator, to search for proofs,and to search for couterexamples. We also touch on relations between logic programming and automated reasoning.

AC-coupled strip detectors biased with a FOXFET transistor structure have been studied. Measurement results for the basic operational characteristics of the FOXFET are presented together with a brief description of the physics underlying its operation. Radiation effects were studied using photons from a {sup 137}Cs source. Changes in the FOXFET characteristics as a function of radiation dose up to 1 MRad are reported. Results about the effect of radiation on the noise from a FOXFET biased detector are described. 13 refs.

A simple way to relate Lorentz transformations to a finite and discrete model of counter firings is presented. We first abstract from counter firings with finite resolution to rational fraction velocities and a finite step-length. Discrete Lorentz transformations and quantized rotations follow. These are encoded by three integers and a triangle with integer sides: the RQM Triangle. The double slit experiment allows us to observe quantized space steps and measure invariant step lengths for any particle in rational ratio to one such length for any convenient reference particle. A discrete version of the Mandelstam analysis of elastic and anelastic scattering is implied. The results fit naturally into the bit-string formalism used in earlier work.

Supersymmetric models with explicit R-parity violation can induce new rare decay modes of the Z boson into single supersymmetric particles. Here, the rate and signature for one such decay, Z {yields} {tilde {upsilon}} {gamma}, is examined, where it is found that the rate is at least an order of magnitude smaller than that for the process Z{yields} H{gamma}, even with larger values of the R-parity violating couplings.

Inspired by Stillman Drake's definition of Galilean Units as those for which (L/T{sup 2} = ({pi}{sup 2}/8)g) where g is any finite, constant acceleration measured in units of L and T, we construct a kinematical dimensional analysis based only on two universal, dimensionless constants. For the linear relation between L and T we use Einsteinian Units L/ = (1)c. For orbiting masses negligible compared to some mass unit M, we use Keplerian Units based on his second law (L{sup 2}/T = (1/2{pi})h/M). Then the unit for orbital angular momentum is {Dirac h}, independent of the mass scale. This allows us to define dimensionless coupling constants f{sup 2} = {beta} = v/c where v is the orbital velocity. We find that most of relativistic quantum mechanics requires only kinematical units. Dynamical units require a mass scale with universal significance, set by the orbital velocity v = c (or f{sup 2} = 1). In dimensional form this becomes M = (1)({Dirac h}c/G){sup 1/2}. Assuming baryon number conservation, the fact that the proton is the lightest stable baryon allows us to calculate {Dirac h}c/Gm{sub p}{sup 2} {approx} 1.7 {times} 10{sup 38} as the Beckenstein number of the proton--the number of bits of information …

The phase structure of a field theory can have two qualitatively different forms- the less familiar of which involves high temperature symmetry breaking and low temperature symmetry restoration and is dubbed an inverse phase transition. After a general discussion of such inverse phase transitions we present an application of this phenomenon in which the symmetry under consideration is baryon number. The model has the virtues of generating the observed quark-antiquark asymmetry (with no explicit baryon number violating interactions) while simultaneously providing the dark matter known to exist in galactic halos and clusters of galaxies. Constraints from cosmology and particle physics highly constrain the mass of this dark matter candidate: 40GeV < m{sub phi} < 50GeV. In this way we demonstrate our main conclusion: the exotic phase structure of the inverted form can give rise to novel, predictive and testable cosmological phenomenon.

The ability of a country to follow sustainable development paths is determined to a large extent by the capacity or capabilities of its people and its institutions. Specifically, capacity-building in the UNCED terminology encompasses the country's human, scientific, technological, organizational, institutional, and resource capabilities. A fundamental goal of capacity-building is to enhance the ability to pose, evaluate and address crucial questions related to policy choices and methods of implementation among development options. As a result the United Nations Conference on Environment and Development (UNCED) Agenda 21 planning process has identified the need for better methods by which information can be transferred between industrialized nations and developing nations. The reasons for better methods of information transfer include facilitating decisions related to sustainable development and building the capacity of developing nations to better plan their future in both an economical and environmentally sound manner. This paper is a discussion on mechanisms for providing information and technologies available for presenting the information to a variety of cultures and levels of technical literacy. Consideration is given to access to information technology as well as to the cost to the user. One concept discussed includes an Engineering Partnership'' which brings together the talents and resources …

P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.

In the past few years, atom clusters with diameters in the range of 2--20 nm of a variety of materials, including both metals and ceramics, have been synthesized by evaporation and condensation in high-purity gases and subsequently consolidated in situ under ultrahigh vacuum conditions to create nanophase materials. These new utlrafine-grained materials have properties that are often significantly different and considerably improved relative to those of their coarser-grained counterparts owing to both their small grain-size scale and the large percentage of their atoms in grain boundary environments. Since their properties can be engineered during the synthesis and processing steps, cluster-assembled materials appear to have significant potential for the introduction of a hierarchy of both structure and properties. Some of the recent research on nanophase materials related to properties and scale are reviewed and some of the possibilities for synthesizing hierarchical nanostructures via cluster assembly are considered.

Distributions of the A-center (oxygen-vacancy) in neutron silicon detectors have been studied using Deep Level Transient Spectroscopy. A-centers have been found to be nearly uniformly distributed in the silicon water depth for medium resistivity (0.1 {minus} 0.2 k{Omega}-cm) silicon detectors. A positive filling pulse was needed to detect the A-centers in high resistivity (>4 k{Omega}-cm) silicon detectors, and this effect was found to be dependent on the oxidation temperature. A discussion of this effect is presented. 16 refs.

The TPC's (Time Projection Chamber) used in E-810 at the AGS (Alternating Gradient Synchroton) were exposed to silicon ion fluxes equivalent to more than 10{sup 7} minimum ionizing particles per second to measure the distortion of the electric field caused by positive ions in the drift region. Results of these tests are presented and the consequences for the TPC based experiment at RHIC (Relativistic Heavy Ion Collider) are discussed.

An approximation method is being developed to predict the dynamic plastic response of rigid, strain-hardening structures. This method is analogous to the instantaneous mode techniques used to treat rigid, perfectly plastic structures in that deflection shape involving a number of arbitrary functions of time selected, based on static deformation profiles. Two stress fields are associated with the deflection shape: one satisfies the equations of motion with appropriate boundary and continuity conditions, and the other satisfies the strain-hardening constitutive relation with appropriate boundary and smoothness conditions. The method is illustrated using the case of a simply-supported beam with a central plastic region.

Future high luminosity low energy machines will need low mass tracking chambers to order to minimize multiple scattering of the relatively low momentum tracks produced at these facilities. A drift chamber using a helium based gas rather than a conventional argon based gas would greatly reduce the amount of multiple scattering. This paper summarizes measurements of the drift velocity and position resolution for gas mixtures of helium with CO{sub 2} and isobutane and helium with DME. Good spatial resolutions are obtained. A design of a drift chamber with only 0.12% of a radiation length (gas plus wire) over a 60 cm tracking distance is presented.

Spin-polarized electron photoemission has been investigated for strained III--V compounds; (1) strained In{sub x}Ga{sub 1-x}As epitaxially grown on a GaAs substrate, and (2) strained GaAs grown on a GaAs{sub 1-x}P{sub x} buffer layer. The lattice mismatched heterostructure results in a highly strained epitaxial layer, and electron spin polarization as high as 90% has been observed.

The Next Linear Collider (NLC) currently under investigation at SLAC requires a positron source with a flux of about 8.6 {times} 10{sup 13} particles per second, 14.4 times more than the SLC source. Based on the SLC experience, a source for NLC is proposed that can be realized with present accelerator technology. It consists of a 7 GeV S-band electron linac, a solid moving target, a 1.8 GeV L-band positron accelerator and a pre-damping ring with a large acceptance. The pre-damping ring performs positron accumulation and the matching of the positron source emittance to the NLC main damping ring acceptance. The scheme and parameters of the NLC positron source are given and the expected source performance is computed.

The Atmospheric Neutrino Deficit defines a region in {Delta}m{sup 2}-sin{sup 2}2{theta} space which ought to be conclusively tested in a long-baseline experiment. This talk sets out a region to cover (which may change as more data is analyzed) and translates that region into an L/E. I present exclusion curves for different experiments based on their distance and their precision; I conclude that an experiment which can detect oscillations down to 1% located at 1200 km will cleanly test the allowed region from Kamioka and IMB. I then describe the techniques which can perform such a measurement and outline both a detector capable of performing such an experiment and some of the systematic problems we might expect.

The purpose of this workshop is to focus attention on, and to stimulate the scientific exploitation of, the natural polarization properties of bend-magnet synchrotron radiation at the ALS -- for research in biology, materials science, physics, and chemistry. The topics include: The Advanced Light Source; Magnetic Circular Dichroism and Differential Scattering on Biomolecules; Tests of Fundamental Symmetries; High {Tc} Superconductivity; Photoemission from Magnetic and Non-magnetic Solids; Studies of Highly Correlated Systems; and Instrumentation for Photon Transport and Polarization Measurements.

A system is currently being developed at Lawrence Livermore Laboratory to treat transuranic wastes by means of a mediated electrochemical oxidation process. The process involves generating Ag({sup ++}) from a solution of silver nitrate and nitric acid in an electrochemical cell. Ag({sup ++}) is highly reactive and is capable of attacking many organic and inorganic substances. In particular, if a mixture of particles containing transuranic and other scrap metal oxides is allowed to react with Ag({sup ++}) in a nitric acid solution, the transuranic oxides will dissolve and can be removed with the solution leaving the other insoluble oxides behind. The dissolution of the transuranic oxides by reactions with Ag({sup ++}) occurs due to further oxidation to higher valence states and the formation of soluble ions such as MO{sub 2}{sup +} and MO{sub 2}{sup ++}. 7 refs., 5 figs., 1 tab.

As part of the research and development program in preparation for a possible B Factory at SLAC, a group has been studying various aspects of HEP computing. In particular, the group is investigating the use of UNIX for all computing, from data acquisition, through analysis, and word processing. A summary of some of the results of this study will be given, along with some personal opinions on these topics.

As the old saying goes, If you have no objective, any road will take your there.'' So it is with the audit checklist. The checklist is the primary tool for providing order to Quality Assurance audit activities. With a well-planned and well-defined checklist, success is achievable. Without a checklist, the auditor has a disjointed, disorganized activity and no place to document his or her failed efforts. A number of formal quality programs which include audits as one of their program elements require the audit to be performed using a checklist or procedures to document what the auditor reviewed and what he or she found. It is the intent of this paper to provide the reader with the some insight as to the value of the checklist; the varieties of checklists that can be constructed; the pitfalls of improper application; and the success that can be achieved when the checklist has been properly researched, developed, and deployed.

Recent progress in molecular-dynamics studies of radiation-induced crystalline-to-amorphous transition in the ordered intermetallic compounds of the Cu-Ti system is discussed. The effect of irradiation was simulated by the generation of Frenkel pairs,which resulted in both the formation of stable point defects and chemical disorder upon defect recombination. The thermodynamic, structural and mechanical responses of the compounds during irradiation were determined by monitoring changes in the system potential energy, volume expansion, pair correlation function, diffraction patterns, and elastic constants. It was found that the intermetallics Cu{sub 4}Ti{sub 3}, CuTi, and CuTi{sub 2} could be rendered amorphous by the creation of Frenkel pairs, but Cu{sub 4}Ti could not, consistent with experimental observations during electron irradiation. However, the simulations showed that Cu{sub 4}Ti did become amorphous when clusters of Frenkel pairs were introduced, indicating that this compound may be susceptible to amorphization by heavy-ion bombardment. A generalization of the Lindemann criterion was used to develop a thermodynamic description of solid-state amorphization as a disorder- induced melting process.