A 1-D model for highly sensitive tubular reactors (open access)

A 1-D model for highly sensitive tubular reactors

We consider the steady state operation of wall-cooled, fixed-bed tubular reactors. In these reactors the temperature rise ..delta..T must normally be limited to small fractions of the adiabatic temperature rise ..delta..T/sub ad/, both to avoid runaway and maintain product selectivity. Yet ..delta..T/..delta..T/sub ad/ << 1 can only occur if eta = t/sub dif//t/sub reac/ << 1, where t/sub dif/ is the timescale on which heat escapes the reactor by ''diffusing'' to the cooled walls, and t/sub reac/ is the timescale over which the reaction occurs. So here we use asymptotic methods based on eta << 1 to analyze the 2-d reactor equations, and find the radial concentration and temperature profiles to leading order in eta. We then obtain a 1-d model of the reactor by substituting these asymptotically correct profiles into the reactor equations and averaging over r. This model, the ..cap alpha..-model, is identical to the standard (Beek and Singer) 1-d model, except that the reactor's overall heat transfer coefficient U is a decreasing function of the temperature rise ..delta..T. This occurs because as ..delta..T increases, the reaction becomes increasingly concentrated near r = 0, causing a decreased heat transfer efficiency through the reactor's walls. By comparing it with …
Date: January 1, 1987
Creator: Hagan, P. S.; Herskowitz, M. & Pirkle, J. C.
Object Type: Article
System: The UNT Digital Library
2-D ACAR measurements of Ni/sub 3/A1 (open access)

2-D ACAR measurements of Ni/sub 3/A1

In connection with a detailed study of the electronic structure and stability of the aluminides (Ni,Fe)/sub 3/Al, 2-D ACAR positron annihilation measurements were made on a Ni/sub 3/Al single crystal to study the Fermi surface. The results for Ni/sub 3/Al have been compared with results for pure Ni. Strong similarities were found for the electronic structures of these materials. Theoretical calculations of the Fermi surface for Ni/sub 3/Al are in good agreement with the experimental results. The GAMMA/sub 16/ sheet, not previously observed in any experiment, has now been observed for the first time in Ni/sub 3/Al. 14 refs., 10 figs.
Date: July 1987
Creator: Smedskjaer, L. C.; DasGupta, A.; Legnini, D. G. & Stahulak, M. D.
Object Type: Report
System: The UNT Digital Library
2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures (open access)

2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures

The work done consists of three parts: optimizing the disk-and-washer (DAW) structure at ..beta.. = 0.5662 corresponding to E = 200 MeV; comparing the DAW structure with the side-coupled (SCS) structure at various values of beta, ranging from ..beta.. = 0.4569 and E = 116 MeV to ..beta.. = 0.7131 and E = 400 MeV; and re-optimizing the DAW structure at ..beta.. = 0.7131. 4 refs., 51 figs., 41 tabs.
Date: December 1, 1987
Creator: Larry, L.D. Jr.
Object Type: Report
System: The UNT Digital Library
2, Pulse-mode expansions and refractive indices in plane-wave propagation (open access)

2, Pulse-mode expansions and refractive indices in plane-wave propagation

This memo presents basic background theory for treating simultaneous propagation of electromagnetic pulses of various colors, directed along a common ray, through a molecular vapor. The memo discusses some techniques for expanding the positive frequency part of the transverse electric field into pulse modes, characterized by carrier frequencies within a modulated envelope. We discuss, in the approximation of plane waves with slowly varying envelopes, a set of uncoupled envelope equations in which a polarization mode-envelope acts as a source for an electric-field envelope. These equations, when taken with a prescription for the polarization field, are the basic equations of plane-wave pulse propagation through a molecular medium. We discuss two ways of treating dispersive media, one based upon expansions in the frequency domain and the other based in the time domain. In both cases we find envelope equations that involve group velocities. This memo represents a portion of a more extensive treatment of propagation to be presented separately. Many of the equations presented here have been described in various books and articles. They are collected and described here as a summary and review of contemporary theory.
Date: June 20, 1987
Creator: Shore, B. W.; Sacks, R.; Karr, T.; Morris, J. & Paisner, J. A.
Object Type: Report
System: The UNT Digital Library
3-D hybrid PIC code to model the tilt mode in FRCs (open access)

3-D hybrid PIC code to model the tilt mode in FRCs

The results from QN3D are presented. QN3D is a 3-dimensional hybrid particle-in-cell code designed to run efficiently on the Cray-2 Multiprocessor. The chief application has been to the tilt mode instability in FRCs. QN3D accepts as input, the magnetic field, the ion particle density and the ion temperature on a two-dimensional r-z grid. These quantities are interpolated to the rest of the cartesian grid under the assumption of azimuthal symmetry. The particles are initialized with random numbers chosen according to the particle distributions input from the equilibrium code. The runs done here used equilibria computed by EQV, a kinetic equilibrium code.
Date: June 1, 1987
Creator: Horowitz, E. J. & Shumaker, D. E.
Object Type: Article
System: The UNT Digital Library
4,5-methylenedithio-4',5'-propylenedithiotetrathiafulvalene (MPT) and 4,5-ethylenedithio-4',5'-propylenedithiotetrathiafulvalene (EPT) (open access)

4,5-methylenedithio-4',5'-propylenedithiotetrathiafulvalene (MPT) and 4,5-ethylenedithio-4',5'-propylenedithiotetrathiafulvalene (EPT)

The title electron donors, unsymmetrical analogs of Bis(ethylenedithio)tetrathiafulvalene, are synthesized. The utility of /sup 252/Cf Plasma Desorption Mass Spectrometry in the characterization and purity determinations is also reported.
Date: January 1, 1987
Creator: Kini, A. M.; Tytko, S. F.; Hunt, J. E. & Williams, J. M.
Object Type: Article
System: The UNT Digital Library
7-GeV Advanced Photon Source Conceptual Design Report (open access)

7-GeV Advanced Photon Source Conceptual Design Report

During the past decade, synchrotron radiation emitted by circulating electron beams has come into wide use as a powerful, versatile source of x-rays for probing the structure of matter and for studying various physical processes. Several synchrotron radiation facilities with different designs and characteristics are now in regular operation throughout the world, with recent additions in this country being the 0.8-GeV and 2.5-GeV rings of NSLS at Brookhaven National Laboratory. However, none of the operating facilities has been designed to use a low-emittance, high-energy stored beam, together with modern undulator devices, to produce a large number of hard x-ray beams of extremely high brilliance. This document is a proposal to the Department of Energy to construct and operate high-energy synchrotron radiation facility at Argonne National Laboratory. We have now chosen to set the design energy of this facility at 7.0 GeV, with the capability to operate at up to 7.5 GeV.
Date: April 1, 1987
Creator: unknown
Object Type: Report
System: The UNT Digital Library
88-Inch Cyclotron newsletter (open access)

88-Inch Cyclotron newsletter

Activities at the 88-Inch Cyclotron are discussed. Increased beam time demand and operation of the ECR source and cyclotron are reported. Experimental facility improvements are reported, including improvements to the High Energy Resolution Array and to the Recoil Atom Mass Analyzer, a new capture beamline, development of a low background counting facility. Other general improvements are reported that relate to the facility computer network and electronics pool. Approved heavy nuclei research is briefly highlighted. Also listed are the beams accelerated by the cyclotron. (LEW)
Date: February 1, 1987
Creator: Stokstad, R.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
300 Area Process Trench Sediment Analysis Report (open access)

300 Area Process Trench Sediment Analysis Report

This report describes the results of a sampling program for the sediments underlying the Process Trenches serving the 300 Area on the Hanford reservation. These Process Trenches were the subject of a Closure Plan submitted to the Washington State Department of Ecology and to the US Environmental Protection Agency in lieu of a Part B permit application on November 8, 1985. The closure plan described a proposed sampling plan for the underlying sediments and potential remedial actions to be determined by the sample analyses results. The results and proposed remedial action plan are presented and discussed in this report. 50 refs., 6 figs., 8 tabs.
Date: December 1, 1987
Creator: Zimmerman, M.G. & Kossik, C.D.
Object Type: Report
System: The UNT Digital Library
1985 consumer segmentation: Assessment of the market for conservation in the Northwest: Phase 2 (open access)

1985 consumer segmentation: Assessment of the market for conservation in the Northwest: Phase 2

This report presents information on consumer attitudes toward conservation, past and intended conservation behaviors, and utility-sponsored conservation program participation levels. The information was collected by means of random telephone surveys of households in Idaho, Oregon, Washington, and Western Montana. Pacific Northwest Laboratory (PNL) conducted analyses of the survey results for the Bonneville Power Administration (BPA) to obtain a better understanding of consumer attitudes and behaviors and to facilitate conservation program planning, design, and marketing.
Date: May 1987
Creator: Bailey, B. M.; Hattrup, M. P.; Nordi, R. T.; Shankle, S. A. & Ivey, D. L.
Object Type: Report
System: The UNT Digital Library
1985 Libby Reservoir Angler Census: May 13-October 31, 1987 [i.e. 1985] : Interim Report. (open access)

1985 Libby Reservoir Angler Census: May 13-October 31, 1987 [i.e. 1985] : Interim Report.

An intensive creel and economic survey was conducted on Libby Reservoir from May 13 through October 31, 1985. This research was part of a larger effort to quantify the existing reservoir fishery and the effects of dam operation on this fishery. Census techniques incorporated direct interviews and electronic car counters installed at all established boat ramp access sites. A total of 4243 angling party interviews, 2379 car counter interviews and 719 economic surveys were conducted on Libby Reservoir. Interviewed anglers fished for 52,146 hours. Estimated pressure was 518,916 hours or 93,500 angler days equivalent to 2.10 angler days per acre. Eight percent of the total estimated angler days or 7436 fishing grips occurred on the Canadian portion of the reservoir. Boat anglers expended over 96% of the total effort. Anglers caught an estimated 617,097 fish during the creel period, 97% (597,380 fish) of which were kokanee. The majority (98%) of the kokanee harvested were caught on the US portion of the reservoir. Harvest of Salmo spp. was estimated at 15,334 fish. Whitefish and brook trout harvest was estimated at 1273 and 48 fish, respectively. Nongame fish species were almost nonexistent in the creel and estimated harvest was less than 0.5% …
Date: May 1, 1987
Creator: Chisholm, Ian & Hamlin, Paul
Object Type: Report
System: The UNT Digital Library
1985 primary heating fuel use and switching: Assessment of the market for conservation in the Northwest: Phase 2 (open access)

1985 primary heating fuel use and switching: Assessment of the market for conservation in the Northwest: Phase 2

This report presents information on the types of primary heating fuels used in residences in the Pacific Northwest region and how the heating fuels affect the level of investment in energy conservation measures (ECMs) by occupants of the residences. The types of heating fuel switching that occurred during the past two years (1983-1985) is also presented. The information was collected from random telephone surveys of households in Idaho, Oregon, Washington, and western Montana. The Pacific Northwest Laboratory (PNL) conducted analyses of the survey results for the Bonneville Power Administration (BPA) to obtain a better understanding of consumer attitudes and behaviors and to facilitate conservation program planning, design, and marketing. This report covers the following hypotheses: (1) there is no relationship between investing in ECMs and the type of primary heating fuel used in a residence; and (2) there is no relationship between the decision to switch to a new primary heating fuel during 1983-1985 and the original type of primary heating fuel used in the residence.
Date: May 1, 1987
Creator: Hattrup, M. P.; Nordi, R. T. & Ivey, D. L.
Object Type: Report
System: The UNT Digital Library
1986 Environmental Monitoring Report (open access)

1986 Environmental Monitoring Report

SNLL conducts various research activities which have the potential for release of hazardous materials or radionuclides to the environment. Potential emissions include tritium, depleted uranium, metals, solvents, and common laboratory chemicals. SNLL handles gram quantities of tritium, kilogram quantities of depleted uranium, but only microcurie quantities of other isotopes. Airborne tritium released in 1986 during research at the TRL was 760 curies (predominantly the oxide form) and 24 millicuries of tritiated water (HTO) was discharged in the liquid effluent. The quantity of depleted uranium released during 1986 was less than 10 microcuries (or 22 grams - analysis near background level) from both liquid and airborne effluents.
Date: April 1, 1987
Creator: Devlin, T. K.
Object Type: Report
System: The UNT Digital Library
The 1986 residential occupant survey (open access)

The 1986 residential occupant survey

In 1986, Pacific Northwest Laboratory developed the Residential Occupant Survey-Spring '86, which was implemented. The overall purpose of the study was to collect demographic, attitudinal, and behavioral data related to the use and conservation of electricity in dwellings participating in the Bonneville Power Administration's End-Use Load and Conservation Assessment Program (ELCAP). Information was collected on the respondents' perceptions of the energy efficiency of their dwelling, temperature the dwelling was kept when people were at home and awake during the last heating season, which rooms, if any, were not heated during the last heating season, number of times the dwelling was unoccupied for at least one week, number of times pets were let out of the dwelling per day, attitudes toward energy use and conservation and several socio-demographic variables such as age, sex, and total household income. The results of the data analyses showed age to be an important factor for reported indoor temperature and perceived energy efficiency of the dwelling. The results also showed that almost 60% of the ELCAP occupants do not heat one or more rooms during the heating season, and almost 45% of the ELCAP dwellings were unoccupied for at least one week during the reporting period. …
Date: April 1, 1987
Creator: Ivey, D.L. & Alley, P.K.
Object Type: Report
System: The UNT Digital Library
1987 DOE review: First collider run operation (open access)

1987 DOE review: First collider run operation

This review covers the operations of the first run of the 1.8 TeV superconducting super collider. The papers enclosed cover: PBAR source status, fixed target operation, Tevatron cryogenic reliability and capacity upgrade, Tevatron Energy upgrade progress and plans, status of the D0 low beta insertion, 1.8 K and 4.7 K refrigeration for low-..beta.. quadrupoles, progress and plans for the LINAC and booster, near term and long term and long term performance improvements.
Date: May 1, 1987
Creator: Childress, S.; Crawford, J.; Dugan, G.; Edwards, H.; Finley, D. A.; Fowler, W. B. et al.
Object Type: Report
System: The UNT Digital Library
1987 Federal interim storage fee study: A technical and economic analysis (open access)

1987 Federal interim storage fee study: A technical and economic analysis

This document is the latest in a series of reports that are published annually by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). This information in the report, which was prepared by E.R. Johnson Associates under subcontract to PNL, will be used by the DOE to establish a payment schedule for interim storage of spent nuclear fuel under the Federal Interim Storage (FIS) Program, which was mandated by the Nuclear Waste Policy Act of 1982. The information in this report will be used to establish the schedule of charges for FIS services for the year commencing January 1, 1988. 13 tabs.
Date: September 1, 1987
Creator: unknown
Object Type: Report
System: The UNT Digital Library
1987 Gordon Research Conference on Physical Metallurgy. (open access)

1987 Gordon Research Conference on Physical Metallurgy.

None
Date: July 24, 1987
Creator: unknown
Object Type: Article
System: The UNT Digital Library
1987 Oak Ridge model conference: Proceedings (open access)

1987 Oak Ridge model conference: Proceedings

A conference sponsored by the United States Department of Energy (DOE), was held on waste management. Topics included waste management, site remediation, waste minimization, economic and social aspects of waste management, and waste management training. Several case studies of US DOE facilities are included. Individual projects are processed separately for the data bases. (CBS)
Date: October 1, 1987
Creator: unknown
Object Type: Article
System: The UNT Digital Library
1987 Oak Ridge model conference: Proceedings: Volume 2, Environmental protection (open access)

1987 Oak Ridge model conference: Proceedings: Volume 2, Environmental protection

See the abstract for Volume I for general information on the conference. Topics discussed in Volume II include data management techiques for environmental protection efforts, the use of models in environmental auditing, in emergency plans, chemical accident emergency response, risk assessment, monitoring of waste sites, air and water monitoring of waste sites, and in training programs. (TEM)
Date: January 1, 1987
Creator: unknown
Object Type: Article
System: The UNT Digital Library
1987 Oak Ridge model conference: Proceedings: Volume I, Part 2, Waste Management (open access)

1987 Oak Ridge model conference: Proceedings: Volume I, Part 2, Waste Management

A conference sponsored by the United States Department of Energy (DOE) was held on Waste Mangement. Topics discussed were waste stabilization technologies regulations and standards, innovative treatment technology, waste stabilization projects. Individual projects are processed separately for the data bases. (CBS)
Date: January 1, 1987
Creator: unknown
Object Type: Article
System: The UNT Digital Library
1987 Oak Ridge model conference: Proceedings: Volume I, Part 3, Waste Management (open access)

1987 Oak Ridge model conference: Proceedings: Volume I, Part 3, Waste Management

A conference sponsored by the United States Department of Energy (DOE), was held on waste management. Topics of discussion were transuranic waste management, chemical and physical treatment technologies, waste minimization, land disposal technology and characterization and analysis. Individual projects are processed separately for the data bases. (CBS)
Date: January 1, 1987
Creator: unknown
Object Type: Article
System: The UNT Digital Library
A 20mK temperature sensor (open access)

A 20mK temperature sensor

We are developing a 20mK temperature sensor made of neutron transmutation doped (NTD) germanium for use as a phonon detector in a dark matter search. We find that NTD germanium thermistors around 20mK have resistances which are a strong function of temperature, and have sufficient sensitivity to eventually reach a base line rms energy fluctuation of 6eV at 25mK. Further work is needed to understand the extreme sensitivity of the thermistors to bias power. 13 refs., 18 figs.
Date: November 1987
Creator: Wang, N.; Sadoulet, B.; Shutt, T.; Beeman, J.; Haller, E.E.; Lange, A. et al.
Object Type: Article
System: The UNT Digital Library
3DFEMWATER: A three-dimensional finite element model of water flow through saturated-unsaturated media (open access)

3DFEMWATER: A three-dimensional finite element model of water flow through saturated-unsaturated media

The 3DFEMWATER model is designed to treat heterogeneous and anisotropic media consisting of as many geologic formations as desired, consider both distributed and point sources/sinks that are spatially and temporally dependent, accept the prescribed initial conditions or obtain them by simulating a steady state version of the system under consideration, deal with a transient head distributed over the Dirichlet boundary, handle time-dependent fluxes due to pressure gradient varying along the Neumann boundary, treat time-dependent total fluxes distributed over the Cauchy boundary, automatically determine variable boundary conditions of evaporation, infiltration, or seepage on the soil-air interface, include the off-diagonal hydraulic conductivity components in the modified Richards equation for dealing with cases when the coordinate system does not coincide with the principal directions of the hydraulic conductivity tensor, give three options for estimating the nonlinear matrix, include two options (successive subregion block iterations and successive point interactions) for solving the linearized matrix equations, automatically reset time step size when boundary conditions or source/sinks change abruptly, and check the mass balance computation over the entire region for every time step. The model is verified with analytical solutions or other numerical models for three examples.
Date: August 1, 1987
Creator: Yeh, G.T.
Object Type: Report
System: The UNT Digital Library
Ab initio calculation of ground- and excited-state properties of surfaces. [Ge(111):As and Si(111):As] (open access)

Ab initio calculation of ground- and excited-state properties of surfaces. [Ge(111):As and Si(111):As]

A new approach for surface studies using the density functional formalism for structural determination and a first principles many-body theory for the quasiparticle surface state energies is discussed. The many-body calculation involves the evaluation of the electron self-energy operator including both local fields and dynamical screening effects. Results for the Ge(111):As and Si(111):As surface are in excellent agreement with recent angle-resolved photoemission data and show a substantially larger gap between the empty and occupied surface states in comparison to local density functional calculations.
Date: April 1, 1987
Creator: Louie, S.G.
Object Type: Article
System: The UNT Digital Library