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A 2D electrostatic PIC code for the Mark III Hypercube (open access)

A 2D electrostatic PIC code for the Mark III Hypercube

We have implemented a 2D electrostastic plasma particle in cell (PIC) simulation code on the Caltech/JPL Mark IIIfp Hypercube. The code simulates plasma effects by evolving in time the trajectories of thousands to millions of charged particles subject to their self-consistent fields. Each particle`s position and velocity is advanced in time using a leap frog method for integrating Newton`s equations of motion in electric and magnetic fields. The electric field due to these moving charged particles is calculated on a spatial grid at each time by solving Poisson`s equation in Fourier space. These two tasks represent the largest part of the computation. To obtain efficient operation on a distributed memory parallel computer, we are using the General Concurrent PIC (GCPIC) algorithm previously developed for a 1D parallel PIC code.
Date: December 31, 1990
Creator: Ferraro, R. D.; Liewer, P. C. & Decyk, V. K.
System: The UNT Digital Library
Dynamic load balancing in a concurrent plasma PIC code on the JPL/Caltech Mark III hypercube (open access)

Dynamic load balancing in a concurrent plasma PIC code on the JPL/Caltech Mark III hypercube

Dynamic load balancing has been implemented in a concurrent one-dimensional electromagnetic plasma particle-in-cell (PIC) simulation code using a method which adds very little overhead to the parallel code. In PIC codes, the orbits of many interacting plasma electrons and ions are followed as an initial value problem as the particles move in electromagnetic fields calculated self-consistently from the particle motions. The code was implemented using the GCPIC algorithm in which the particles are divided among processors by partitioning the spatial domain of the simulation. The problem is load-balanced by partitioning the spatial domain so that each partition has approximately the same number of particles. During the simulation, the partitions are dynamically recreated as the spatial distribution of the particles changes in order to maintain processor load balance.
Date: December 31, 1990
Creator: Liewer, P. C.; Leaver, E. W.; Decyk, V. K. & Dawson, J. M.
System: The UNT Digital Library
Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter) (open access)

Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of the alkali metal, and low electrical resistance, other high temperature components of the cell face equally demanding requirements. The beta{double_prime} alumina solid electrolyte (BASE), the seal between the BASE ceramic and its metallic transition to the hot alkali metal (liquid or vapor) source, and metallic components of the device are exposed to hot liquid alkali metal. Modification of AMTEC components may also be useful in optimizing the device for particular operating conditions. In particular, a potassium AMTEC may be expected to operate more efficiently at lower temperatures.
Date: December 31, 1991
Creator: Williams, R. M.; Jeffries-Nakamura, B.; Underwood, M. L.; Ryan, M. A.; O`Connor, D. & Kikkert, S.
System: The UNT Digital Library
Direct Conversion of Methane to Methanol in a Non-Isothermal Catalytic Membrane Reactor (open access)

Direct Conversion of Methane to Methanol in a Non-Isothermal Catalytic Membrane Reactor

The direct partial oxidation of CH{sub 4} to CH{sub 3}OH has been studied in a non-permselective, non-isothermal catalytic membrane reactor system. A cooling tube introduced coaxially inside a tubular membrane reactor quenches the product stream rapidly so that further oxidation of CH{sub 3}OH is inhibited. Selectivity for CH{sub 3}OH formation is significantly higher with quenching than in experiments without quenching. For CH{sub 4} conversion of 4% to 7% CH{sub 3}OH selectivity is 40% to 50% with quenching and 25% to 35% without quenching.
Date: December 31, 1993
Creator: Noble, R. D. & Falconer, J. L.
System: The UNT Digital Library
Vada Phillips Felder: Educator hosted MLK's visit to Fort Worth in 1959 (open access)

Vada Phillips Felder: Educator hosted MLK's visit to Fort Worth in 1959

Text of an obituary for Vada Phillips Felder, including background biographical information, statements from those who knew her, and a summary of and interview about hosting Dr. Martin Luther King, Jr. during a trip he took to Fort Worth.
Date: July 31, 2008
Creator: Smith, Diane
System: The Portal to Texas History
[Advance Proof of Harper's Magazine Article: The Easy Chair] (open access)

[Advance Proof of Harper's Magazine Article: The Easy Chair]

Article by Bernard DeVoto detailing the situation that led Dr. Homer P. Rainey to be fired from his position as President of the University of Texas, including his supposed sympathy for "communists and homosexuals" and his attempts to increase opportunities for African American students. DeVoto goes on to describe the impact this will have on higher education and freedom of speech as a whole.
Date: July 31, 1945
Creator: De Voto, Bernard, 1897-1955
System: The Portal to Texas History