This paper discusses dendritic sidebranching; anisotropic surface tension; light scattering at the crystal-melt interface; and succinonitrite-dye mixtures.

Reaction pathways leading to the formation and cleavage of a transition metal-carbon bond at various oxidation states of the metal occupy a central position in understanding many enzymatic reactions and designing catalysts. The report is divided into six parts that (1) focus on the homolysis vs heterolysis of a C-Cr(III) bond, (2) describes a unique chain reaction and a S{sub E}2 reaction I{sub 2} and RCrL{sup 2+}, (3) concerns the oxidation of organochromium(III) complexes by dihalide and pseudo-dihalide radical anions generated by pulse radiolysis, (4) concentrates on the oxidation mechanism of RCr(H{sub 2}O){sup 2+} and the fate of RCr(H{sub 2}O){sup 3+} as well as the corresponding reduction potentials, (5) extends study of organocobalt complexes with attention to reduction induced cleavages of a transition metal-carbon bond, and (6) describes the crystallization of ((CH{sub 3}){sub 4}N)(Co(dmgBF{sub 2}){sub 2}py) and reports its molecular structure as determined by x-ray diffraction. 182 refs., 25 figs., 16 tabs. (BM)

During the 1988/1989 run at the Fermilab Tevatron, the CDF detector collected {approx equal}4.1 pb{sup {minus}1} of p{bar p} data at {radical}s = 1.8 TeV. The main goals of this run being physics at high p{sub t}, the CDF trigger was tuned'' for maximizing signals from Z{sup 0}s, Ws, t-quarks, etc. As such, compared to the high p{sub t} physics, the b-physics program was of secondary importance other than that which would be used for background calculations. Also, CDF had no vertex chamber capability for seeing displaced vertices. However, significant b-quark, physics results are evident in two data samples; inclusive electrons and inclusive J/{psi} where J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}. We can then ask ourselves, given all this, why is it that CDF is able to do b-quark physics The answer is that nature has been kind enough to provide b-quarks at an extremely high rate at the Tevatron. The production cross-section for b{bar b} production is quite large. In the rest of this paper, I will try to specify the goals for b-physics using the inclusive electrons and J/{psi} signals for the 1988/1989 data set. I will then provide a brief look at the data, and will finish with …

Low energy collisions involving neutral excited states of hydrogen are being studied with vacuum ultraviolet spectroscopy. Atomic hydrogen is generated by focusing an energetic pulse of ArF, KrF, or YAG laser light into a cell of molecular hydrogen, where a plasma is created near the focal point. The H{sub 2} molecules in and near this region are dissociated, and the cooling atomic hydrogen gas is examined with laser and dispersive optical spectroscopy. In related experiments, we are also investigating neutral H + O and H + metal {minus} atom collisions in these laser-generated plasmas.

The safety and optimal performance of large, commercial, light-water reactors require the knowledge at all time of the neutron-flux distribution in the core. In principle, this information can be obtained by solving the time-dependent neutron diffusion equations. However, this approach is complicated and very expensive. Sufficiently accurate, real-time calculations (time scale of approximately one second) are not yet possible on desktop computers, even with fast-running, nodal kinetics codes. A semi-experimental, nodal synthesis method which avoids the solution of the time-dependent, neutron diffusion equations is described. The essential idea of this method is to approximate instantaneous nodal group-fluxes by a linear combination of K, precomputed, three-dimensional, static expansion-functions. The time-dependent coefficients of the combination are found from the requirement that the reconstructed flux-distribution agree in a least-squares sense with the readings of J ({ge}K) fixed, prompt-responding neutron-detectors. Possible numerical difficulties with the least-squares solution of the ill-conditioned, J-by-K system of equations are brought under complete control by the use of a singular-value-decomposition technique. This procedure amounts to the rearrangement of the original, linear combination of K expansion functions into an equivalent more convenient, linear combination of R ({le}K) orthogonalized modes'' of decreasing magnitude. Exceedingly small modes are zeroed to eliminate any …

Thin-layer chromatography (TLC) is a broadly applicable separation technique. It offers many advantages over high performance liquid chromatography (HPLC), such as easily adapted for two-dimensional separation, for whole-column'' detection and for handling multiple samples, etc. However, due to its draggy development of detection techniques comparing with HPLC, TLC has not received the attention it deserves. Therefore, exploring new detection techniques is very important to the development of TLC. It is the principal of this dissertation to present a new detection method for TLC -- indirect fluorometric detection method. This detection technique is universal sensitive, nondestructive, and simple. This will be described in detail from Sections 1 through Section 5. Section 1 and 3 describe the indirect fluorometric detection of anions and nonelectrolytes in TLC. In Section 2, a detection method for cations based on fluorescence quenching of ethidium bromide is presented. In Section 4, a simple and interesting TLC experiment is designed, three different fluorescence detection principles are used for the determination of caffeine, saccharin and sodium benzoate in beverages. A laser-based indirect fluorometric detection technique in TLC is developed in Section 5. Section 6 is totally different from Sections 1 through 5. An ultrasonic effect on the separation of …

We study the sensitivity of pion interferometry in {bar p}p and {bar p}p collisions at ISR energies to the resonance abundance. We show that those data are not compatible with the full resonance fractions predicted by the Lund model. The preliminary S+S and O+Au data at 200 GeV are, however, not incompatible with the Lund predictions, although their sensitivity to resonances is significantly weaker than in the pp/{bar p}p case.

This is a summary of some of the many recent results from the CERN and Fermilab colliders, presented for an audience of nuclear, medium-energy, and elementary particle physicists. The topics are jets and QCD at very high energies, precision measurements of electroweak parameters, the remarkably heavy top quark, and new results on the detection of the large flux of B mesons produced at these machines. A summary and some comments on the bright prospects for the future of hadron colliders conclude the talk. 39 refs., 44 figs., 3 tabs.

A new way to characterize the performance of the LBL HIF ion source has been found. In the LBL source, ions are drawn from an arc-generated plasma reservoir in which the electrons are confined by a negative-biased switch'' mesh. Stagnation of the plasma is prevented by absorption of the excess ion flow on this mesh. The ion beam is generated by an external negative voltage that provides Child-Langmuir extraction of the ions through the switch mesh. We elucidate the physics requirements of the source and deduce switch mesh parameters needed for successful operation. 2 refs., 2 figs.

A review of recent developments in the quantum differential calculus. The quantum group GL[sub q](n) is treated by considering it as a particular quantum space. Functions on SL[sub q] (n) are defined as a subclass of functions on GL[sub q](n). The case of SO[sub q](n) is also briefly considered. These notes cover part of a lecture given at the XIX International Conference on Group Theoretic Methods in Physics, Salamanca, Spain 1992.

Within High-Level Waste Management (HLWM), CAMs and VAMPs are currently considered Class B equipment, therefore, alarm conditions associated with the CAMs and VAMPs result in an Unusual Occurrence or Off-Normal notification and subsequent occurrence reporting. Recent equipment difficulties associated with Continuous Air Monitors (CAMs) and Victoreen Area Radiation Monitors (VAMPs) have resulted in a significant number of notification reports. These notification have the potential to decrease operator sensitivity to the significance of specific CAM and VAMP failures. Additionally, the reports are extremely costly and are not appropriate as a means for tracking and trending equipment performance. This report provides a technical basis for a change in Waste Management occurrence reporting categorization for specific CAM and VAMP failure modes.

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The Nuclear Weapons Reduction Initiative announced by President Bush on September 27, 1991, is described herein as set forth in Defense Secretary Cheney`s Nuclear Arsenal Reduction Order issued September 28, 1991. The implications of the Bush Initiative for improved nuclear weapons safety are assessed in response to a request by US Senators Harkin, Kennedy, and Wirth to the Lawrence Livermore National Laboratory that the author prepare such an assessment. The author provides an estimate of the number of nuclear tests needed to accomplish a variety of specified warhead safety upgrades, then uses the results of this estimate to answer three questions posed by the Senators. These questions concern pit reuse and the number of nuclear tests needed for specified safety upgrades of those ballistic missiles not scheduled for retirement, namely the Minuteman III, C4, and D5 missiles.

The goal of this program is the construction of an x-ray laser in the kilovolt regime. Recent experimental results indicate that a new technique for the generation of strong amplification of x-ray wavelengths is feasible. It involves the combination of (1) a new ultrahigh brightness subpicosecond laser technology and (2) a recently discovered unique mode of strong-field interaction, particularly applicable to molecules. A concept of molecular x-ray design emerges from the considerations which matches the mode of excitation to the structure of the molecular system. The molecular approach enables the combination of very highly electronically excited conditions with an environment characteristic of dense cold matter, a general situation exceptionally conducive to x-ray amplification. Both high efficiency and wavelength tunability are intrinsic features of this method. Recent results discussed in this report are revealing important characteristics of the molecular strong-field coupling pertinent to this goal. A continued program of research is proposed to evaluate this method for the production of x-ray amplification in the kilovolt region.

The information presented in this engineering note can be of value to others who wish to predict pumping times and water content of vessels containing G-IO material. Four predictions of the water content of the G-IO in the D-Zero Central Calorimeter (CC) are given. Experience from pumping on the NW A cryostat was used to help predict the pumpdown time required for the CC. The actual pumpdown time and water removal from the CC agrees quite well with those predicted which gives confidence for future predictions done using the information presented in this engineering note. A listing of the predictions and actual CC pumpdown particulars is given.

A review of recent developments in the quantum differential calculus. The quantum group GL{sub q}(n) is treated by considering it as a particular quantum space. Functions on SL{sub q} (n) are defined as a subclass of functions on GL{sub q}(n). The case of SO{sub q}(n) is also briefly considered. These notes cover part of a lecture given at the XIX International Conference on Group Theoretic Methods in Physics, Salamanca, Spain 1992.

The Mine Waste Working Group discussed the nature and possible contributions to the solution of this class of waste problem at length. There was a consensus that the mine waste problem presented some fundamental differences from the other classes of waste addresses by the Develop On-Site Innovative Technologies (DOIT) working groups. Contents of this report are: executive summary; stakeholders address the problems; the mine waste program; current technology development programs; problems and issues that need to be addressed; demonstration projects to test solutions; conclusion-next steps; and appendices.

The IBM ASCI Blue-Pacific System is a scalable, distributed/shared memory architecture designed to reach multi-teraflop performance. The IBM SP pieces together a large number of nodes, each having a modest number of processors. The system is designed to accommodate a mixed programming model as well as a pure message-passing paradigm. We examine a number of applications on this architecture and evaluate their performance and scalability.

This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development Department (WPDD) as specified in the Waste Package Implementation Plan and Waste Package Plan. The design data request addressed herein is: (1) Characterize the conceptual 44 boiling water reactor (BWR) uncanistered fuel (UCF) waste package (WP) to show that the design is feasible for use in the MGDS environment. The purpose of this analysis is to respond to a concern that the long-term disposal thermal issues for the UCF waste package do not preclude UCF waste package compatibility with the MGDS. The objective of this analysis is to provide thermal parameter information for the conceptual UCF WP design under nominal MGDS repository conditions. The results are intended to show that the design has a reasonable chance to meet the MGDS design requirements for normal MGDS operation and to provide the required guidance to determining the major design issues for future design efforts. Future design efforts will focus on UCF design changes as further design and operations information becomes available.

The ORNL Heat Pump Design Model is a FORTRAN-IV computer program to predict the steady-state performance of conventional, vapor compression, electrically-driven, air-to-air heat pumps in both heating and cooling modes. This model is intended to serve as an analytical design tool for use by heat pump manufacturers, consulting engineers, research institutions, and universities in studies directed toward the improvement of heat pump performance. The Heat Pump Design Model allows the user to specify: system operating conditions, compressor characteristics, refrigerant flow control devices, fin-and-tube heat exchanger parameters, fan and indoor duct characteristics, and any of ten refrigerants. The model will compute: system capacity and COP (or EER), compressor and fan motor power consumptions, coil outlet air dry- and wet-bulb temperatures, air- and refrigerant-side pressure drops, a summary of the refrigerant-side states throughout the cycle, and overall compressor efficiencies and heat exchanger effectiveness. This report provides thorough documentation of how to use and/or modify the model. This is a revision of an earlier report containing miscellaneous corrections and information on availability and distribution of the model--including an interactive version.

The work summarizes results of the authors' studies on the energetic ion transport induced by sawtooth oscillations in tokamaks. The main attention is paid to description of physical mechanisms responsible for the transport. In addition to overview, the work contains new material. The new results concern the resonant interaction of the particles and the electromagnetic field of the sawtooth crash. In particular, it is discovered that the dominant harmonic of the crash (m = n = 1) can lead to stochastic motion of particles having large orbit width (potatoes). Regular motion of potatoes and quasi-stagnation particles in the presence of an n = 1 mode is studied, and their characteristic displacements associated with quick switching on/off the mode are found.

With the rapid developments in experimental and theoretical fusion energy research towards more geometric details, visualization plays an increasingly important role. In this paper we will give an overview of how visualization can be used to compare and contrast some different configurations for future fusion reactors. Specifically we will focus on the stellarator and tokamak concepts. In order to gain understanding of the underlying fundamental differences and similarities these two competing concepts are compared and contrasted by visualizing some key attributes.

A three-field model to study drift-resistive, low-frequency waves in low-beta, non-axisymmetric plasmas [J.L.V. Lewandowski, Phys. Plasmas, 4 (11) 4023 (1997)] is used to analyze the effect of the inhomogeneities in the stellarator magnetic field on the fastest (linear) growth rate, gamma. Extensive numerical calculations for a toroidal heliac show that not all Fourier components in the representation of the equilibrium configuration are important as far as gamma is concerned.

The 1994 SIAM Forum examined applied mathematics in industry with a particular focus on the ingredients for a successful career. The presentations were a mix of panel discussions and individual speakers. In their presentations and discussions, members of four different panels explored: the experiences of recent graduates whose first job was in industry; the hiring process from the point of view of managers; the place of mathematics and of mathematicians in smaller firms; the insights of industrial applied mathematicians whose terminal degree is not in mathematics. Another view of careers in business, industry, and government was provided by a presentation of preliminary data from SIAM`s Mathematics in Industry (MII) project. Finally, techniques for building bridges from academia to industry were described by several experienced speakers. In spite of the diverse backgrounds of the Forum`s panelists and speakers, the central ideas they presented were strikingly similar. These common themes are outlined here. The Forum program is appended to this report.