Surfactant studies for bench-scale operation (open access)

Surfactant studies for bench-scale operation

A phase II study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: (1) the refurbishment of the high-pressure, high-temperature reactor autoclave, (2) the completion of four coal liquefaction runs with Pittsburgh [number sign]8 coal, two each with and without sodium lignosulfonate surfactant, and (3) the development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.
Date: December 30, 1992
Creator: Hickey, G.S. & Sharma, P.K.
Object Type: Report
System: The UNT Digital Library
The study of redox-active inorganic substituents of cellulase enzymes. Quarterly report, 25 August--25 November 1993 (open access)

The study of redox-active inorganic substituents of cellulase enzymes. Quarterly report, 25 August--25 November 1993

Cellulase (CBHI) was modified by bis (2,2- bipyridine) ruthenium (II) and the modified enzyme was assayed for cellulase activity using p- nitrophenyl beta-D-cellobioside as substrate. Absorption spectroscopy of native and modified CBHI was also conducted.
Date: December 31, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Surfactant studies for bench-scale operation. First quarterly technical progress report, July 1, 1992--September 30, 1992 (open access)

Surfactant studies for bench-scale operation. First quarterly technical progress report, July 1, 1992--September 30, 1992

A phase II study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: (1) the refurbishment of the high-pressure, high-temperature reactor autoclave, (2) the completion of four coal liquefaction runs with Pittsburgh {number_sign}8 coal, two each with and without sodium lignosulfonate surfactant, and (3) the development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.
Date: December 30, 1992
Creator: Hickey, G. S. & Sharma, P. K.
Object Type: Report
System: The UNT Digital Library
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.
Object Type: Article
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.
Object Type: Article
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.
Object Type: Article
System: The UNT Digital Library
SP-100 operational life model. Fiscal Year 1990 annual report (open access)

SP-100 operational life model. Fiscal Year 1990 annual report

This report covers the initial year`s effort in the development of an Operational Life Model (OLM) for the SP-100 Space Reactor Power System. The initial step undertaken in developing the OLM was to review all available documentation from GE on their plans for the OLM and on the degradation and failure mechanisms envisioned for the SP-100. In addition, the DEGRA code developed at JPL, which modelled the degradation of the General Purpose Heat Source based Radioisotope Thermoelectric Generator (GPHS-RTG), was reviewed. Based on the review of the degradation and failure mechanisms, a list of the most pertinent degradation effects along with their key degradation mechanisms was compiled. This was done as a way of separating the mechanisms from the effects and allowing all of the effects to be incorporated into the OLM. The emphasis was on parameters which will tend to change performance as a function of time and not on those that are simply failures without any prior degradation.
Date: December 14, 1990
Creator: Ewell, R. & Awaya, H.
Object Type: Report
System: The UNT Digital Library