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Configuration Management Program Plan. Revision 1
Westinghouse Savannah River Company (WSRC) has established a configuration management (CM) plan to execute the SRS CM Policy and the requirements of the DOE Order 4700.1. The Reactor Restart Division (RRD) has developed its CM Plan under the SRS CM Program and is implementing it via the RRD CM Program Plan and the Integrated Action Plan. The purpose of the RRD CM program is to improve those processes which are essential to the safe and efficient operation of SRS production reactors. This document provides details of this plan.
Configuration Manual Polarized Proton Collider at RHIC
In this report, the authors present their design to accelerate and store polarized protons in RHIC, with the level of polarization, luminosity, and control of systematic errors required by the approved RHIC spin physics program. They provide an overview of the physics to be studied using RHIC with polarized proton beams, and a brief description of the accelerator systems required for the project.
Configuration Manual Polarized Proton Collider at RHIC
In this report we present our design to accelerate and store polarized protons in RHIC, with the level of polarization, luminosity, and control of systematic errors required by the approved RHIC spin physics program. We provide an overview of the physics to be studied using RHIC with polarized proton beams, and a brief description of the accelerator systems required for the project.
Configuration of Tatum Salt Dome, Lamar County, Mississippi. Technical Letter: Dribble-1
This report addresses the configuration of Tatum Salt Dome, Lamar County, Mississippi.
Configuration of the Top of the Floridan Aquifer Southwest Florida Water Management District and Adjacent Areas
This map depicts the approximate top of the rock that composes the Floridan aquifer. The contours represent the elevation of the top of the Floridan aquifer to mean sea level.
Configuration review of TFCX design options
As part of the preconceptual design effort of the Tokamak Fusion Core Experiment (TFCX), several candidate design options have been explored in order to identify a preferred option that will be developed in further detail during the conceptual design phase of the TFCX program. The development of the TFCX concepts has been a collaborative effort between the Princeton Plasma Physics Laboratory (PPPL) and the Fusion Engineering Design Center (FEDC) with broad community input. The design options being considered include an all-superconducting design, a superconducting/copper toroidal field (TF) hybrid design, and several different all-copper configurations.
Configuration sensitivity of residual p-n interactions
An empirical method to extract the p-n interaction of the last proton and neutron in nearly any nucleus is used to discuss global features of the p-n systematics and evidence for configuration sensitivity in special regions. 11 refs., 2 figs.
Configuration space Faddeev calculations
The detailed study of few-body systems provides one of the most effective means for studying nuclear physics at subnucleon distance scales. For few-body systems the model equations can be solved numerically with errors less than the experimental uncertainties. We have used such systems to investigate the size of relativistic effects, the role of meson-exchange currents, and the importance of quark degrees of freedom in the nucleus. Complete calculations for momentum-dependent potentials have been performed, and the properties of the three-body bound state for these potentials have been studied. Few-body calculations of the electromagnetic form factors of the deuteron and pion have been carried out using a front-form formulation of relativistic quantum mechanics. The decomposition of the operators transforming convariantly under the Poincare group into kinematical and dynamical parts has been studies. New ways for constructing interactions between particles, as well as interactions which lead to the production of particles, have been constructed in the context of a relativistic quantum mechanics. To compute scattering amplitudes in a nonperturbative way, classes of operators have been generated out of which the phase operator may be constructed. Finally, we have worked out procedures for computing Clebsch-Gordan and Racah coefficients on a computer, as well as giving procedures for dealing with the multiplicity problem.
Configuration space Faddeev calculations
The detailed study of few-body systems provides one of the most precise tools for studying the dynamics of nuclei and nucleons. This research program consists of a careful theoretical study of few-body systems and methods for modeling these systems. During the past year several aspects of this program were completed. Brief summaries are given of work on the following topics: The relativistic three quark problem; the relativistic Balian-Brezin method; spin in light front quantum mechanical models; proton-deutron scattering and reactions; point form relativistic quantum mechanics of constituents; solutions of quantum mechanical anharmonic oscillators; shift operators and the U(N) multiplicity problem.
Configuration Space Faddeev Calculations. Progress Report, 1 November 1991--31 October 1992
The detailed study of few-body systems provides one of the most precise tools for studying the dynamics of nuclei and nucleons. This research program consists of a careful theoretical study of few-body systems and methods for modeling these systems. During the past year several aspects of this program were completed. Brief summaries are given of work on the following topics: The relativistic three quark problem; the relativistic Balian-Brezin method; spin in light front quantum mechanical models; proton-deutron scattering and reactions; point form relativistic quantum mechanics of constituents; solutions of quantum mechanical anharmonic oscillators; shift operators and the U(N) multiplicity problem.
Configuration space Faddeev calculations. Progress report, 1 November 1992--31 October 1993
The detailed study of few-body systems provides one of the most precise tools for studying the dynamics of nuclei and nucleons. This research program consists of a careful theoretical study of few-body systems and methods for modeling these systems. Brief summaries are given on several aspects of this program including the following: the use of configuration-space Faddeev equations to solve the proton-deuteron scattering problem with long-range Coulomb interactions; calculations of the triton binding energy; inclusion of dynamical vacuum structures in Hamiltonian light-front dynamics; constraints in Bethe-Salpeter models; signature of quantum chaos; applications of point form relativistic quantum mechanics collective nuclear models and the symplectic group Sp (6,R); and anharmonic oscillators and quantum mechanics systems in nonconstant magnetic fields.
Configuration space Faddeev calculations. Progress report, January 1, 1988--December 31, 1988
The detailed study of few-body systems provides one of the most effective means for studying nuclear physics at subnucleon distance scales. For few-body systems the model equations can be solved numerically with errors less than the experimental uncertainties. We have used such systems to investigate the size of relativistic effects, the role of meson-exchange currents, and the importance of quark degrees of freedom in the nucleus. Complete calculations for momentum-dependent potentials have been performed, and the properties of the three-body bound state for these potentials have been studied. Few-body calculations of the electromagnetic form factors of the deuteron and pion have been carried out using a front-form formulation of relativistic quantum mechanics. The decomposition of the operators transforming convariantly under the Poincare group into kinematical and dynamical parts has been studies. New ways for constructing interactions between particles, as well as interactions which lead to the production of particles, have been constructed in the context of a relativistic quantum mechanics. To compute scattering amplitudes in a nonperturbative way, classes of operators have been generated out of which the phase operator may be constructed. Finally, we have worked out procedures for computing Clebsch-Gordan and Racah coefficients on a computer, as well as giving procedures for dealing with the multiplicity problem.
Configuration space Faddeev calculations. Progress report, November 1, 1993--October 31, 1994
The detailed study of few-body systems provides one of the most precise tools for studying the dynamics of nuclei and nucleons. Our research program consists of a careful theoretical study of few-body systems and methods for modeling these systems. During the past year we have completed several aspects of this program.
Configuration space methods in the three-nucleon problem
The assumptions underlying the formulation and solution of the Schroedinger equation for three nucleons in configuration space are reviewed. Those qualitative aspects of the two-nucleon problem which play an important role in the trinucleon are discussed. The geometrical aspects of the problem are developed, and the importance of the angular momentum barrier is demonstrated. The Faddeev-Noyes formulation of the Schroedinger equation is motivated, and the boundary conditions for various three-body problems is reviewed. The method of splines is shown to provide a particularly useful numerical modelling technique for solving the Faddeev-Noyes equation. The properties of explicit trinucleon solutions for various two-body force models are discussed, and the evidence for three-body forces is reviewed. The status of calculations of trinucleon observables is discussed, and conclusions are presented. 40 refs., 14 figs.
Configuration space representation for micro-mechanism function
This paper describes the configuration space representation of mechanical function and shows how it supports the design of micro-mechanisms. The domain characteristics of curved geometry, joint play, and custom joints render traditional design tools inappropriate, but configuration spaces can model these characteristics. They represent the quantitative and the qualitative aspects of kinematic function in a concise geometric format that helps designers visualize system function under a range of operating conditions, find and correct design flaws, study joint play, and optimize performance. The approach is demonstrated on a surface micromachined counter meshing gear discrimination device developed at Sandia National Laboratories.
A configuration space toolkit for automated spatial reasoning: Technical results and LDRD project final report
A robot`s configuration space (c-space) is the space of its kinematic degrees of freedom, e.g., the joint-space of an arm. Sets in c-space can be defined that characterize a variety of spatial relationships, such as contact between the robot and its environment. C-space techniques have been fundamental to research progress in areas such as motion planning and physically-based reasoning. However, practical progress has been slowed by the difficulty of implementing the c-space abstraction inside each application. For this reason, we proposed a Configuration Space Toolkit of high-performance algorithms and data structures meeting these needs. Our intent was to develop this robotics software to provide enabling technology to emerging applications that apply the c-space abstraction, such as advanced motion planning, teleoperation supervision, mechanism functional analysis, and design tools. This final report presents the research results and technical achievements of this LDRD project. Key results and achievements included (1) a hybrid Common LISP/C prototype that implements the basic C-Space abstraction, (2) a new, generic, algorithm for constructing hierarchical geometric representations, and (3) a C++ implementation of an algorithm for fast distance computation, interference detection, and c-space point-classification. Since the project conclusion, motion planning researchers in Sandia`s Intelligent Systems and Robotics Center have been using the CSTk libcstk.so C++ library. The code continues to be used, supported, and improved by projects in the ISRC.
Configuration Studies and Recommendations for the ILC Damping Rings
We describe the results of studies comparing differentoptions for the baseline configuration of the ILC damping rings. Theprincipal configuration decisions apply to the circumference, beamenergy, lattice type, and technology options for key components,including the injection/extraction kickers and the damping wigglers. Toarrive at our recommended configuration, we performed detailed studies ofa range of lattices representing a variety of different configurationoptions; these lattices are described in Chapter 2. The results of thevarious studies are reported in chapters covering issues of beamdynamics, technical subsystems, costs, and commissioning, reliability andupgradeability. Our detailed recommendations for the baselineconfiguration are given in Chapter 7, where we also outline furtherresearch and development that is needed before a machine using ourrecommended configuration can be built and operated successfully. In thesame chapter, we suggest possible alternatives to the baselineconfiguration.
Configuration Studies and Recommendations for the ILC DampingRings
We describe the results of studies comparing differentoptions for the baseline configuration of the ILC damping rings. Theprincipal configuration decisions apply to the circumference, beamenergy, lattice type, and technology options for key components,including the injection/extraction kickers and the damping wigglers. Toarrive at our recommended configuration, we performed detailed studies ofa range of lattices representing a variety of different configurationoptions; these lattices are described in Chapter 2. The results of thevarious studies are reported in chapters covering issues of beamdynamics, technical subsystems, costs, and commissioning, reliability andupgradeability. Our detailed recommendations for the baselineconfiguration are given in Chapter 7, where we also outline furtherresearch and development that is needed before a machine using ourrecommended configuration can be built and operated successfully. In thesame chapter, we suggest possible alternatives to the baselineconfiguration.
Configuration Studies and Recommendations for the ILC DampingRings
We describe the results of studies comparing different options for the baseline configuration of the ILC damping rings. The principal configuration decisions apply to the circumference, beam energy, lattice type, and technology options for key components, including the injection/extraction kickers and the damping wigglers. To arrive at our recommended configuration, we performed detailed studies of a range of lattices representing a variety of different configuration options; these lattices are described in Chapter 2. The results of the various studies are reported in chapters covering issues of beam dynamics, technical subsystems, costs, and commissioning, reliability and upgrade ability. Our detailed recommendations for the baseline configuration are given in Chapter 7, where we also outline further research and development that is needed before a machine using our recommended configuration can be built and operated successfully. In the same chapter, we suggest possible alternatives to the baseline configuration.
Configuration studies for a small-aspect-ratio tokamak stellarator hybrid
The use of modulated toroidal coils offers a new path to the tokamak-stellarator hybrids. Low-aspect-ratio configurations can be found with robust vacuum flux surfaces and rotational transform close to the transform of a reverse-shear tokamak. These configurations have clear advantages in minimizing disruptions and their effect and in reducing tokamak current drive needs. They also allow the study of low-aspect-ratio effects on stellarator confinement in small devices.
Configurational analysis of an EBT reactor in various magnetic geometries
Optimization of vacuum field particle confinement in an ELMO Bumpy Torus (EBT) reactor has been considered. Several methods of improving the efficient utilization of magnetic fields and the particle confinement characteristics of a reactor have been analyzed. These include the use of (1) magnets with a large mirror ratio, (2) high field Nb/sub 3/Sn or Nb/sub 3/Sn/NbTi hybrid mirror coils, (3) split-wedge mirror coils, (4) aspect ratio enhancement (ARE) coils, and (5) recently developed field symmetrizing (SYM) coils. Of these, particle drift orbits and three-dimensional tensor pressure equilibrium calculations have shown that the ARE and SYM coils used in conjunction with high field magnets offer the most promise of good plasma performance in a smaller size (up to 50%) EBT reactor. The relative merits of each magnetic configuration are discussed, and the design characteristics are given.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates
This quarter we performed some initial scoping experiments dealing with the diffusive adsorption of petroleum/asphalt and coal molecules on alumina catalysts. In this experiments, the concentration of solute molecules in a bath exposed to the adsorbing solid (alumina) was monitored as a function of time. Because these are only preliminary scoping experiments, no quantitative calculations of diffusivity or adsorption equilibria were made; however, these experiments do demonstrate the feasibility of the finite bath technique for diffusivity determination.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Final technical report, September 20, 1991--September 30, 1996
The overall objective of this project was to investigate the diffusion of coal and petroleum asphaltenes in the pores of a supported catalyst. Experimental measurements together with mathematical modeling was conducted to determine how the diffusion rate of asphaltenes, as well as some model compounds, depended on molecule sizes and shapes. The process of diffusion in the pores of a porous medium may occur by several mechanisms. Hindered diffusion occurs when the sizes of the diffusion molecules are comparable to those of the porous pores through which they are diffusing. Hindered diffusion phenomena have been widely observed in catalytic hydrotreatment of asphaltenes, heavy oils, coal derived liquids, etc. Pore diffusion limitations can be greater in spent catalysts due to the deposition of coke and metals in the pores. In this work, a general mathematical model was developed for the hindered diffusion-adsorption of solute in a solvent onto porous materials, e. g. catalysts, from a surrounding bath. This diffusion model incorporated the nonuniformities of pore structures in the porous media. A numerical method called the Method of Lines was used to solve the nonlinear partial differential equations resulting from the mathematical model. The accuracy of the numerical solution was verified by both a mass balance in the diffusion system and satisfactory agreement with known solutions in several special cases.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, 20 December 1993--20 March 1994
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates, i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. This quarter the authors developed a mathematical diffusion model for spent catalyst with a nonuniform pore structure due to nonuniform coke and metals deposition. Diffusion experiments with both spent extrudates and crushed catalysts were performed. Effective diffusivities were obtained by fitting the experimental data with a diffusion model. The results showed that a skin effect due to coke and metals deposition exists in the coal liquefaction catalysts. The uniform particle model did not satisfactorily represent the diffusion behavior in the spent catalyst extrudates, which gave rise to extremely high tortuosity values. On the other hand, the experimental results were well represented by the nonuniform particle model. Due to deposits in catalyst pores during the coal liquefaction process, the effective diffusivity decreased to a very low value.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, December 20, 1991--March 20, 1992
This quarter we performed some initial scoping experiments dealing with the diffusive adsorption of petroleum/asphalt and coal molecules on alumina catalysts. In this experiments, the concentration of solute molecules in a bath exposed to the adsorbing solid (alumina) was monitored as a function of time. Because these are only preliminary scoping experiments, no quantitative calculations of diffusivity or adsorption equilibria were made; however, these experiments do demonstrate the feasibility of the finite bath technique for diffusivity determination.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, December 20, 1994--March 20, 1995
This quarter, GPC column efficiency and resolution were tested. Better resolution and separation of petroleum asphaltenes were obtained in GPC by connecting four columns (1000{Angstrom}, 1000{Angstrom}, 500{Angstrom}, 500{Angstrom} pore sizes, respectively) in series. A good linear column calibration curve was obtained using several polystyrene standards with molecular weights ranging from 500 to 5 {times} 10{sup 4}. The molecular weight distribution of a petroleum asphaltenes was approximated by the polystyrene calibration curve.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, December 20, 1995--March 20, 1996
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry? This quarter, adsorptive diffusion of both coal and petroleum asphaltenes in THF into porous catalysts were performed. A mathematical model with linear adsorption isotherm for asphaltene diffusion was developed. The molecular weight distribution of both asphaltenes were ascertained by GPC using polystyrene standards. The asphaltene diffusion data were simulated fairly well by the mathematical model, and linear adsorption constants were obtained for asphaltene fractions with different equivalent polystyrene molecular weights.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, June 20, 1993--September 20, 1993
This quarter, we measured the surface areas and effective diffusivities for fresh, spent and regenerated unimodal Criterion 324 and bimodal EXP-AO-60 catalysts. The results showed that the surface areas for spent catalysts decreased greatly due to coke formation and metal deposition during coal liquefaction process. After regeneration, the catalyst surface areas were partially or completely restored. Adsorption equilibrium experiments showed that the adsorption isotherms for quinoline in cyclohexane with these six sample of catalysts could be well represented by Freundlich isotherms. The effective diffusivities with these catalysts were obtained by fitting experimental data with the diffusional model. The results indicated that the effective diffusivity for fresh bimodal catalyst with larger pore size was greater than that for fresh unimodal catalyst with a smaller pore size. After the catalysts were used in a coal liquefaction process, the effective diffusivities decreased to less than 1% of those for fresh catalysts. When the spent catalysts were regenerated in air, the effective diffusivites were recovered to 35--50% of those for fresh catalysts.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, June 20, 1995--September 20, 1995
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. This quarter, three petroleum and two coal asphaltenes were prepared from petroleum asphalts and coal derived solids separately by solvent extraction.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, June 20--September 30, 1996
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. The study involves three tasks: Relationship between effective intrapore diffusion coefficients, molecular size, and pore geometry; Effects of solvent composition, solute concentration, and temperature on the molecular configuration and diffusion rate of coal and petroleum asphaltenes in catalyst pores; and Assessment of diffusional limitations in aged catalysts. This quarter, uptake experiments of coal and petroleum asphaltenes into porous catalyst were performed using different initial concentrations, temperatures, and solvents. The adsorption-diffusion parameters were obtained by simulating the experimental data with the mathematical model. The results showed that the adsorption constants for coal asphaltene fractions at 0.5 mg/cm{sup 3} initial concentration are less than those at 0.05 mg/cm{sup 3}, indicating the non-linearity of coal asphaltene adsorption on porous catalyst. Comparison of uptake results using different solvents showed that the adsorption constants with solvent toluene are much larger than those with THF solvent. The effect of temperature on the adsorptive uptake was complex, with the adsorptivity for coal asphaltenes at 35 C exceeding that at 25 C in the lower (< 10{sup 3}) molecular weight region; while the adsorptivities for petroleum asphaltenes are about the same at 20, 35, and 50 C.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, March 20, 1994--June 20, 1994
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates in catalyst pore structures. This quarter, the authors developed a mathematical diffusion model for catalysts with a nonuniform pore structure during the adsorptive diffusion process due to the adsorbed layer of solute molecules on the catalyst pore walls. Diffusion experiments with quinoline and polystyrene were performed. Effective diffusivities were obtained by fitting the experimental data with a diffusion model. Results showed that the uniform pore model did not satisfactorily represent the diffusion behavior of larger polystyrene molecules, which gave rise to very high tortuosity values. The shrinking pore model better represented the adsorptive diffusion uptake behavior of a solute from the surrounding bath, especially for a diffusing solute with larger molecular size. Adsorption of solute molecules on the catalyst pore walls further restricts the diffusion rate due to increased steric and hydrodynamic hindrance factors. The tortuosity factor could also increase during adsorptive diffusion processes due to the increased constrictions caused by the adsorbed solute molecules.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, March 20, 1995--June 20, 1995
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, March 20, 1996--June 20, 1996
This quarter, hindered diffusion of one coal and two petroleum asphaltenes was studied by adsorptive uptake in THF from a bath surrounding a commercial NiMo/Al{sub 2}O{sub 3} catalyst. Several asphaltene fractions were defined via SEC (size exclusion chromatography), with the molecular weight of each fraction being determined by its elution characteristics using polystyrene standards. It was found that both the coal and petroleum asphaltenes have very broad molecular weight distributions; however, the molecular weights of the coal asphaltenes (50--1000) were much smaller than those of the two petroleum asphaltenes (300--10000 and 300--20000 respectively). Simulation results showed that even though the properties of coal and petroleum asphaltenes were quite different, the values of model parameters for the fractions of the three asphaltenes had the same trend; with increasing molecular weight of the fraction, the adsorption constant monotonically increases, and the effective diffusivity decreases. The experimental diffusion data of the three asphaltenes were well represented by similar mathematical models.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, September 20, 1991--December 20, 1991
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry.
Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Quarterly progress report, September 20, 1993--December 20, 1993
Objective is to determine the relation between the size and shape of coal and petroleum macromolecules and their diffusion rates in catalyst pore structures. During this past quarter, experiments using narrow molecular weight polystyrenes and alumina extrudates made in the lab were carried out (cyclohexane was used as solvent). Freundlich and Langmuir constants for the adsorption equilibrium isotherms were determined for these materials. A Langmuir isotherm was a slightly better fit for the data. Results follow the expected trend and may be used to predict the adsorption isotherm for any polystyrene and alumina combination. 8 figs, 19 refs, 4 tabs.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates
Objective is to determine the relation between the size and shape of coal and petroleum micromolecules and their diffusion rates in catalyst pore structures. Diffusivity measurements will be performed with aged catalysts from coal liquefaction pilot plants. During this period, equilibrium adsorption experiments were carried out to determine the adsorption isotherm needed in the data analysis. The equilibrium isotherm for quinoline in cyclohexane with fresh Shell 324 (Ni-Mo/Al[sub 2]O[sub 3]) catalyst was found to be nonlinear and well represented by the Freundlich adsorption isotherm. The effective diffusivity was found to be less than the estimated pore diffusivity for nonrestrictive diffusion, indicating pore restriction for quinoline diffusion in cyclohexane with Shell 324 catalyst.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. Based on the work done, the following conclusions can be drawn: The intrapore diffusional model can be set up mathematically based on certain assumptions, and the mathematical model can be solved numberically; the numerical solution discussed in this quarterly report can be used for typical situations given suitable values for parameters E, R and n; comparison with known solutions for special cases shows the numerical solution to be accurate.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates. [Mathematical configurational diffusion model]
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. This quarter we made a more comprehensive literature survey concerning configurational diffusion in porous catalysts or catalyst supports. A detailed literature review is reported. Also, a mathematical configurational diffusion model was developed. By using this model, the effective diffusivity for model compounds diffusing in porous media and a linear adsorption constant can be determined by fitting experimental data.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates. Quarterly progress report, December 20, 1992--March 20, 1993
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. This quarter, the investigators several approaches to check the effect of external mass transfer on the diffusion rate. Theoretical analyses and experimental results showed that the external mass transfer effect can be neglected for our experimental conditions.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates. Quarterly progress report, June 20, 1992--September 20, 1992
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. Based on the work done, the following conclusions can be drawn: The intrapore diffusional model can be set up mathematically based on certain assumptions, and the mathematical model can be solved numberically; the numerical solution discussed in this quarterly report can be used for typical situations given suitable values for parameters E, R and n; comparison with known solutions for special cases shows the numerical solution to be accurate.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates. Quarterly progress report, March 20, 1992--June 20, 1992
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. That is, how do the effective intrapore diffusivities depend on molecule configuration and pore geometry. This quarter we made a more comprehensive literature survey concerning configurational diffusion in porous catalysts or catalyst supports. A detailed literature review is reported. Also, a mathematical configurational diffusion model was developed. By using this model, the effective diffusivity for model compounds diffusing in porous media and a linear adsorption constant can be determined by fitting experimental data.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates. Quarterly progress report, [March--June 1993]
The objective of this research is to determine the relationship between the size and shape of coal and petroleum macromolecules and their diffusion rates i.e., effective diffusivities, in catalyst pore structures. Finite bath-type diffusion experiments will be performed using both coal and petroleum-derived macromolecular species, e.g. asphaltenes, as well as model compounds, e.g. porphyrins, polymers, of known molecular size. By monitoring the concentration of solute macromolecules in the bath, the effective intrapore diffusion coefficients will be determined through application of the appropriate diffusion equations. Macromolecular species concentrations will be monitored by size exclusion chromatography (SEC). Relationships will be sought between the size, and shape, e.g. planar, coil, of the diffusing solutes and the pore geometry (pore size distribution) of the catalyst support The effects of molecule configuration and catalyst pore size distribution on the effective intrapore diffusivity will be examined. Specially prepared laboratory catalysts with very narrow pore size distributions and other model porous media, eg. porous Vycor glass, will be utilized in the experiments. Pore structures of all catalysts and other porous media will be characterized by mercury porosimetry and surface area (BET) analysis.
Configurational diffusion of asphaltenes in fresh and aged catalysts extrudates. Quarterly progress report, September 20, 1992--December 20, 1992
Objective is to determine the relation between the size and shape of coal and petroleum micromolecules and their diffusion rates in catalyst pore structures. Diffusivity measurements will be performed with aged catalysts from coal liquefaction pilot plants. During this period, equilibrium adsorption experiments were carried out to determine the adsorption isotherm needed in the data analysis. The equilibrium isotherm for quinoline in cyclohexane with fresh Shell 324 (Ni-Mo/Al{sub 2}O{sub 3}) catalyst was found to be nonlinear and well represented by the Freundlich adsorption isotherm. The effective diffusivity was found to be less than the estimated pore diffusivity for nonrestrictive diffusion, indicating pore restriction for quinoline diffusion in cyclohexane with Shell 324 catalyst.
Configurational Diffusion of Coal Macromolecules
As shown in last quarter's report on the configurational diffusion of coal macromolecules, the hindered diffusion data for both TPP and coal macromolecules were significantly different from the theoretical correlations. In order to evaluate the factors which could lead to this difference an error analysis was conducted, and the detailed results reported herein. Generally, we did not find any errors which could account for the deviation from the theory, and thus we conclude that this deviation is real and can be ascribed to some factor not considered by the hindered diffusion theory, i.e., attractive or repulsive forces. 2 refs., 4 figs., 4 tabs.
Configurational diffusion of coal macromolecules
The objective of our research was to obtain fundamental information regarding the functional dependence of the diffusion coefficient of coal molecules on the ratio of molecule to pore diameter. That is, the objective of our study was to examine the effect of molecule size and configuration on hindered diffusion of coal macromolecules through as porous medium. To best accomplish this task, we circumvented the complexities of an actual porous catalyst by using a well defined porous matrix with uniform capillaric pores, i.e., a track-etched membrane. In this way, useful information was obtained regarding the relationship of molecular size and configuration on the diffusion rate of coal derived macromolecules through a pore structure with known geometry. Similar studies were performed using a pellet formed of porous alumina, to provide a link between the idealized membranes and the actual complex pore structure of real catalyst extrudates. The fundamental information from our study will be useful toward the tailoring of catalysts to minimize diffusional influences and thereby increase coal conversion and selectivity for desirable products. (VC)
Configurational Diffusion of Coal Macromolecules
The objective of this project is to investigate the phenomenon of hindered diffusion of coal macromolecules in idealized porous media. Tasks towards this objective include: Construct a diffusion cell with ideal pore structure for determination of diffusion coefficients, prepare and characterize ideal porous membranes, perform model compound experiments to calibrate and test diffusion apparatus and methodology, prepare and characterize coal macromolecules, and analyze data to evaluate the diffusional behavior of coal macromolecules. This report describes work on the hindered diffusion of tetraphenylporphine and asphaltene. 18 refs., 3 figs., 4 tabs.
Configurational diffusion of coal macromolecules. Final technical report, September 15, 1986--September 14, 1991
The objective of our research was to obtain fundamental information regarding the functional dependence of the diffusion coefficient of coal molecules on the ratio of molecule to pore diameter. That is, the objective of our study was to examine the effect of molecule size and configuration on hindered diffusion of coal macromolecules through as porous medium. To best accomplish this task, we circumvented the complexities of an actual porous catalyst by using a well defined porous matrix with uniform capillaric pores, i.e., a track-etched membrane. In this way, useful information was obtained regarding the relationship of molecular size and configuration on the diffusion rate of coal derived macromolecules through a pore structure with known geometry. Similar studies were performed using a pellet formed of porous alumina, to provide a link between the idealized membranes and the actual complex pore structure of real catalyst extrudates. The fundamental information from our study will be useful toward the tailoring of catalysts to minimize diffusional influences and thereby increase coal conversion and selectivity for desirable products. (VC)
Configurational forces in solid nanostructures
The DOE grant (DE-FG02-99ER45787) to Princeton University, entitled Configurational Forces in Solid Nanostructures, was intended to cover the four-year period from September 1999 to September 2003. Effective 1 July 2003, the PI will relocate from Princeton to join the Harvard faculty. Princeton University will submit the Final Financial Report, the Final Property Report, and the Final Patent Report. The expenditures to date are $261,513 with %8,487 remaining of the awarded amount of $320,000. Harvard University will submit a request for the remaining amount. This Final Technical Report covers from the period between September 1999 to June 2003. Three Ph.D. students, Wei Lu, Yanfei Gao and Wei Hong, admitted to Princeton in the fall of 1998, 1999, 2002, respectively, have been dedicated to this project. Wei Lu earned his Ph.D. in August 2001, and is now an assistant professor at The University of Michigan, Ann Arbor. Yanfei Gao earned his Ph.D. in February 2003, and is now a post-doc at Brown University. The amount of funding covers one student at a time. All three students received first-year fellowships from Princeton University. In the Mechanical and Aerospace Engineering Department, to fulfill a doctoral degree requirement, every student serves as a teaching assistant for three semesters, for which the student is partially paid by the University.
Configurational issues and the evolution of the Mirror Fusion Test Facility upgrade
Lawrence Livermore National Laboratory (LLNL) and the Fusion Engineering Design Center (FEDC) have been conducting a study concerning the upgrade of the Mirror Fusion Test Facility (MFTF). With MFTF-upgrade, program emphasis will begin to shift away from resolving specific issues toward systems integration of all the subsystems of a tandem mirror reactor. All of the upgrade options considered call for deuterium-tritium (D-T)-burning plasmas and, hence, systems integration in the necessary but difficult nuclear environment of a reactor. The preferred option, MFTF-..cap alpha..+T, has three main objectives: (1) to extend physics performance to Q equivalent to 2 in a D-T plasma, (2) to gain experience in tandem mirror systems integration in a nuclear environment, and (3) to provide a unique capability for operating a power-producing section of a fusion reactor at reactor-like parameters. In this paper, the evolution of the MFTF-upgrade configuration to the preferred option is outlined, the important configurational issues for the upgrade are discussed, and a brief description of the selected configuration is presented.
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