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Maximally Concentrating Optics for Photovoltaic Solar Energy Conversion. Technical Progress Report, [July 1, 1985--February 15, 1986] (open access)

Maximally Concentrating Optics for Photovoltaic Solar Energy Conversion. Technical Progress Report, [July 1, 1985--February 15, 1986]

The use of a two-stage concentrator with a fresnel lens primary and a non-imaging dielectric totally internally reflecting secondary, has unique advantages for photovoltaic concentration. This new design has a much larger acceptance angle than the conventional lens-cell concentrating system. In the continuation of this research, an optimally designed prototype which employs a 13.6-cm diameter flat fresnel tons as the primary focusing device, a dielectric compound hyperbolic concentrator (DCHC) as secondary and a 1-cm diameter high-concentration cell for electricity conversion has been built, tested and analyzed. Measurements under sunlight show that it has an angular acceptance of {plus_minus}3.6 degrees, which is dramatically better than the {plus_minus}0.5 degree achievable without a secondary concentrator. This performance agrees well with theoretical ray-tracing predictions. The secondary shows an optical efficiency of (91{plus_minus}2)% at normal incidence. Combining with the primary fresnel tens which has an optical efficiency of (82{plus_minus}2)%, tho two-stage system yields a total optical efficiency of (7l{plus_minus}2)%. The measurement of the system electrical performance yielded a net electrical efficiency of 11.9%. No problems associated with non-uniform cell illumination were found, as evidenced by the excellent fill factor of (79{plus_minus}2)% measured under concentration. The secondary geometrical properties and the optimal two-stage design procedures for …
Date: February 27, 1986
Creator: Winston, R.; O`Gallagher, J. & Ning, X.
System: The UNT Digital Library
Transverse Beam Heating Distributions F. (open access)

Transverse Beam Heating Distributions F.

None
Date: February 27, 1986
Creator: Mills, E.
System: The UNT Digital Library
Effects of Fluctuating Environments on the Selection of High Yielding Microalgae (open access)

Effects of Fluctuating Environments on the Selection of High Yielding Microalgae

Microalgae have the potential of producing biomass with a high content of lipids at high productivities using seawater or saline ground water resources. Microalgal lipids are similar to vegetable oils and suitable for processing to liquid fuels. Engineering cost analysis studies have concluded that, at a favorable site, microalgae cultivation for fuel production could be economically viable. The major uncertainties involve the microalgae themselves: biomass and lipid productivity and culture stability.
Date: February 27, 1987
Creator: Benemann, J. R. & Tillett, D. M.
System: The UNT Digital Library
Cryogenic Control System (open access)

Cryogenic Control System

The control system (CS) for the cryogenic arrangement of the DO Liquid Argon Calorimeter consists of a Texas instruments 560/565 Programmable Logical Controller (PLC), two remote bases with Remote Base Controllers and a corresponding set of input/output (I/O) modules, and a PC AST Premium 286 (IBM AT Compatible). The PLC scans a set of inputs and provides a set of outputs based on a ladder logic program and PID control loops. The inputs are logic or analog (current, voltage) signals from equipment status switches or transducers. The outputs are logic or analog (current or voltage) signals for switching solenoids and positioning pneumatic actuators. Programming of the PLC is preformed by using the TISOFT2/560/565 package, which is installed in the PC. The PC communicates to the PLC through a serial RS232 port and provides operator interface to the cryogenic process using Xpresslink software.
Date: February 27, 1989
Creator: Goloborod'ko, S.
System: The UNT Digital Library
Dynamic Aperture and the Role of BC2 (open access)

Dynamic Aperture and the Role of BC2

None
Date: February 27, 1989
Creator: Parzen, G.
System: The UNT Digital Library
Dynamic Aperture for Lattices With Some ß* = 2 Insertions (open access)

Dynamic Aperture for Lattices With Some ß* = 2 Insertions

None
Date: February 27, 1989
Creator: Parzen, G.
System: The UNT Digital Library
Military and Civilian Satellites in Support of Allied Forces in the Persian Gulf War (open access)

Military and Civilian Satellites in Support of Allied Forces in the Persian Gulf War

This Congressional Research Service Report for Congress explains the use of military and civilian space programs to advance satellites for the support of military action.
Date: February 27, 1991
Creator: Smith, Marcia S.
System: The UNT Digital Library
Confined zone dispersion flue gas desulfurization demonstration (open access)

Confined zone dispersion flue gas desulfurization demonstration

The confined zone dispersion (CZD) process involves flue gas post-treatment, physically located between a boiler's outlet and its particulate collector, which in the majority of cases is an electrostatic precipitator. The features that distinguish this process from other similar injection processes are: Injection of an alkaline slurry directly into the duct, instead of injection of dry solids into the duct ahead of a fabric filter. Use of an ultrafine calcium/magnesium hydroxide, type S pressure-hydrated dolomitic lime. This commercial product is made from plentiful, naturally occurring dolomite. Low residence time, made possible by the high effective surface area of the Type S lime. Localized dispersion of the reagent. Slurry droplets contact only part of the gas while the droplets are drying, to remove up to 50 percent of the S0{sub 2} and significant amounts of NO{sub x}. The process uses dual fluid rather than rotary atomizers. Improved electrostatic precipitator performance via gas conditioning from the increased water vapor content, and lower temperatures. Supplemental conditioning with S0{sub 3} is not believed necessary for satisfactory removal of particulate matter.
Date: February 27, 1992
Creator: unknown
System: The UNT Digital Library
Confined zone dispersion flue gas desulfurization demonstration. [Numerical data only; no text] (open access)

Confined zone dispersion flue gas desulfurization demonstration. [Numerical data only; no text]

Report contains only numerical data, no text.
Date: February 27, 1992
Creator: unknown
System: The UNT Digital Library
Confined zone dispersion flue gas desulfurization demonstration. Volume 1, Quarterly report No. 4, August 1, 1991--October 31, 1991 (open access)

Confined zone dispersion flue gas desulfurization demonstration. Volume 1, Quarterly report No. 4, August 1, 1991--October 31, 1991

The confined zone dispersion (CZD) process involves flue gas post-treatment, physically located between a boiler`s outlet and its particulate collector, which in the majority of cases is an electrostatic precipitator. The features that distinguish this process from other similar injection processes are: Injection of an alkaline slurry directly into the duct, instead of injection of dry solids into the duct ahead of a fabric filter. Use of an ultrafine calcium/magnesium hydroxide, type S pressure-hydrated dolomitic lime. This commercial product is made from plentiful, naturally occurring dolomite. Low residence time, made possible by the high effective surface area of the Type S lime. Localized dispersion of the reagent. Slurry droplets contact only part of the gas while the droplets are drying, to remove up to 50 percent of the S0{sub 2} and significant amounts of NO{sub x}. The process uses dual fluid rather than rotary atomizers. Improved electrostatic precipitator performance via gas conditioning from the increased water vapor content, and lower temperatures. Supplemental conditioning with S0{sub 3} is not believed necessary for satisfactory removal of particulate matter.
Date: February 27, 1992
Creator: unknown
System: The UNT Digital Library
Confined zone dispersion flue gas desulfurization demonstration. Volume 2, Quarterly report No. 4, August 1, 1991--October 31, 1991 (open access)

Confined zone dispersion flue gas desulfurization demonstration. Volume 2, Quarterly report No. 4, August 1, 1991--October 31, 1991

Report contains only numerical data, no text.
Date: February 27, 1992
Creator: unknown
System: The UNT Digital Library
Measurement of D->A Momentum Aperture and Test of D->A Field Qualities (open access)

Measurement of D->A Momentum Aperture and Test of D->A Field Qualities

The data presented here were taken during two shifts dedicated to D->A studies. The goal during both of these study periods was a test of the field quality of the D->A channel devices, but for the first study period on 10/21/91 the TBT system was not operational so we simply measured the transfer efficiency as a function of momentum. The conclusion from these measurements is as follows: (1) The momentum aperture of the D->A channel is smaller than expected. (2) The restriction is in physical space is somewhere near A:IKIK. (3) The field quality of the injection channel devices is adequate.
Date: February 27, 1992
Creator: Halling, Mike
System: The UNT Digital Library
Computer software configuration management plan for 200 East/West Liquid Effluent Facilities (open access)

Computer software configuration management plan for 200 East/West Liquid Effluent Facilities

This computer software management configuration plan covers the control of the software for the monitor and control system that operates the Effluent Treatment Facility and its associated truck load in station and some key aspects of the Liquid Effluent Retention Facility that stores condensate to be processed. Also controlled is the Treated Effluent Disposal System`s pumping stations and monitors waste generator flows in this system as well as the Phase Two Effluent Collection System.
Date: February 27, 1995
Creator: Graf, F. A., Jr.
System: The UNT Digital Library
Electron-proton instability in the IPNS-Upgrade RCS: Part I (open access)

Electron-proton instability in the IPNS-Upgrade RCS: Part I

The electron-proton instability in the IPNS-Upgrade RCS is investigated in this report. A dispersion relation applicable to the coasting beam is derived, and the approximations used are stated in order to facilitate the understanding of the underlying mechanism of the instability. The threshold of instability in terms of neutralization of the circulating beam is found for the IPNS-Upgrade RCS. The dependence of threshold on the beam size and the lattice tune is also studied and its numerical results are presented.
Date: February 27, 1995
Creator: Chae, Yong-Chul
System: The UNT Digital Library
Petroleum supply monthly, February 1995, with data for December 1994 (open access)

Petroleum supply monthly, February 1995, with data for December 1994

Data presented in the Petroleum Supply Monthly (PSM) describe the supply and disposition of petroleum products in the US and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the US (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics. The tables and figures in the Summary Statistics section of the PSM present a time series of selected petroleum data on a US level. The detailed Statistics tables of the PSM present statistics for the most current month available as well as year-to-date. In most cases, the statistics are presented for several geographic areas--the US (50 States and the District of Columbia), five PAD Districts, and 12 Refining Districts. 16 figs., 66 tabs.
Date: February 27, 1995
Creator: unknown
System: The UNT Digital Library
QUEST2: Release 1, SA/Release 1 supporting documents deliverable set (open access)

QUEST2: Release 1, SA/Release 1 supporting documents deliverable set

This document contains deliverables which reflect the last of the System Architecture phase analysis for the Quality, Environmental, Safety Tracking System redesign (QUEST2) project. These deliverables are focused on the final insights required to start functional design of the first QUEST2 release. They include the data definitions, conversion rules, standards for design and user interface, performance criteria, and rules to be followed during the prototyping activity described in the Project Management Plan.
Date: February 27, 1995
Creator: Braaten, F.D.
System: The UNT Digital Library
QUEST2: Sysdtem architecture deliverable set (open access)

QUEST2: Sysdtem architecture deliverable set

This document contains the system architecture and related documents which were developed during the Preliminary Analysis/System Architecture phase of the Quality, Environmental, Safety T-racking System redesign (QUEST2) project. Each discreet document in this deliverable set applies to a analytic effort supporting the architectural model of QUEST2. The P+ methodology cites a list of P+ documents normally included in a ``typical`` system architecture. Some of these were deferred to the release development phase of the project. The documents included in this deliverable set represent the system architecture itself. Related to that architecture are some decision support documents which provided needed information for management reviews that occurred during April. Consequently, the deliverables in this set were logically grouped and provided to support customer requirements. The remaining System Architecture Phase deliverables will be provided as a ``Supporting Documents`` deliverable set for the first release.
Date: February 27, 1995
Creator: Braaten, F. D.
System: The UNT Digital Library
Solute travel time in the vadose zone under RWMC at INEL (open access)

Solute travel time in the vadose zone under RWMC at INEL

Solute transport in the vadose zone under the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering Laboratory (INEL) is considered. The objective is to assess the relative importance of variables involved in modeling the travel time of a conservative solute from ground surface to water table. The vadose zone under RWMC is composed of several layers of basalt flows interceded with sediment layers. The thickness of the layers varies with location. The hydraulic properties also vary. The extents of the variations are large, with standard deviations exceed mean in some instances. The vadose zone is idealized as composed of horizontal layers. Solute transport starts at the ground surface and moves vertically downwards to the water table. The perceived process is one-dimensional. This study used VS2DT, a computer code developed by the US Geological Survey, for simulating solute transport in variably saturated porous media.
Date: February 27, 1995
Creator: Liou, J. C. P. & Tian, J.
System: The UNT Digital Library
Tank 241-BY-103 Tank Characterization Plan. Revision 1 (open access)

Tank 241-BY-103 Tank Characterization Plan. Revision 1

This document is a plan which serves as the contractual agreement between the Characterization Program, Sampling Operations and WHC 222-S Laboratory. The scope of this plan is to provide guidance for the sampling and analysis of samples for tank 241-BY-103.
Date: February 27, 1995
Creator: Schreiber, R. D.
System: The UNT Digital Library
Test Plan for Westinghouse Hanford Company`s Hedgehog Shielded Container, Docket 94-39-7A, Type A Container (open access)

Test Plan for Westinghouse Hanford Company`s Hedgehog Shielded Container, Docket 94-39-7A, Type A Container

This report documents the US Department of Transportation Specification 7A Type A (DOT-7A) compliance testing to be followed for qualification of the Westinghouse Hanford Company`s Hedgehog Shielded Container for use as a Type A packaging. The packaging configurations being tested are intended for liquids and solids, and for air transportation.
Date: February 27, 1995
Creator: Kelly, D. L.
System: The UNT Digital Library
Chaotic behavior control in fluidized bed systems using artificial neural network. Quarterly progress report, October 1, 1996--December 31, 1996 (open access)

Chaotic behavior control in fluidized bed systems using artificial neural network. Quarterly progress report, October 1, 1996--December 31, 1996

Pressurized fluidized-bed combustors (FBC) are becoming very popular, efficient, and environmentally acceptable replica for conventional boilers in Coal-fired and chemical plants. In this paper, we present neural network-based methods for chaotic behavior monitoring and control in FBC systems, in addition to chaos analysis of FBC data, in order to localize chaotic modes in them. Both of the normal and abnormal mixing processes in FBC systems are known to undergo chaotic behavior. Even though, this type of behavior is not always undesirable, it is a challenge to most types of conventional control methods, due to its unpredictable nature. The performance, reliability, availability and operating cost of an FBC system will be significantly improved, if an appropriate control method is available to control its abnormal operation and switch it to normal when exists. Since this abnormal operation develops only at certain times due to a sequence of transient behavior, then an appropriate abnormal behavior monitoring method is also necessary. Those methods has to be fast enough for on-line operation, such that the control methods would be applied before the system reaches a non-return point in its transients. It was found that both normal and abnormal behavior of FBC systems are chaotic. However, …
Date: February 27, 1996
Creator: Bodruzzaman, M. & Essawy, M.A.
System: The UNT Digital Library
Degradation kinetics of polymers in solution: Time-dependence of molecular weight distributions. [Quarterly report, January--March 1996] (open access)

Degradation kinetics of polymers in solution: Time-dependence of molecular weight distributions. [Quarterly report, January--March 1996]

Polymer degradation occurs when polymer chains are broken under the influence of thermal, mechanical, or chemical energy. Chain-end depolymerization and random- and midpoint-chain scission are mechanisms that have been observed in liquid-phase polymer degradation. Here we develop mathematical models, unified by continuous-mixture kinetics, to show how these different mechanisms affect polymer degradation in solution. Rate expressions for the fragmentation of molecular-weight distributions (MWDs) govern the evolution of the MWDs. The governing integro-differential equations can be solved analytically for realistic conditions. Moment analysis for first-order continuous kinetics shows the temporal behavior of MWDs. Chain-end depolymerization yields monomer product and polymer molecular-weight moments that vary linearly with time. In contrast, random- and midpoint-chain scission models display exponential time behavior. The mathematical results reasonably portray experimental observations for polymer degradation. This approach, based on the time evolution of continuous distributions of chain length or molecular weight, provides a framework for interpreting several types of polymer degradation processes.
Date: February 27, 1996
Creator: McCoy, B.J. & Madras, G.
System: The UNT Digital Library
Development of design basis capacity for SNF project systems (open access)

Development of design basis capacity for SNF project systems

An estimate of the design capacity for Spent Nuclear Fuel Project systems producing Multi-Canister Overpacks is developed based on completing fuel processing in a two year period. The design basis capacity for systems relates the desired annual processing rate to potential operating inefficiencies which may be actually experienced to project a design capacity for systems. The basis for estimating operating efficiency factors is described. Estimates of the design basis capacity were limited to systems actually producing the Multi-Canister Overpack. These systems include Fuel Retrieval, K Basin SNF Vacuum Drying, Canister Storage Building support for Staging and Storage, and Hot Vacuum conditioning. The capacity of other systems are assumed to be derived from these system capacities such that systems producing a Multi-Canister Overpack are not constrained.
Date: February 27, 1996
Creator: Pajunen, A.L.
System: The UNT Digital Library
Electrical test structures replicated in silicon-on-insulator material (open access)

Electrical test structures replicated in silicon-on-insulator material

Measurements of the linewidths of submicrometer features made by different metrology techniques have frequently been characterized by differences of up to 90 nm. The purpose of the work reported here is to address the special difficulties that this phenomenon presents to the certification of reference materials for the calibration of linewidth-measurement instruments. Accordingly, a new test structure has been designed, fabricated, and undergone preliminary tests. Its distinguishing characteristics are assured cross-sectional profile geometries with known side-wall slopes, surface planarity, and compositional uniformity when it is formed in mono-crystalline material at selected orientations to the crystal lattice. To allow the extraction of electrical linewidth, the structure is replicated in a silicon film of uniform conductivity which is separated from the silicon substrate by a buried oxide layer. The utilization of a Silicon-On-Insulator (SKI) substrate further allows the selective removal of substrate material from local regions below the reference features, thus facilitating measurements by optical and electron-beam transmission microscopy. The combination of planar feature surfaces having known side-wall slopes is anticipated to eliminate factors which are believed to be responsible for methods divergence in linewidth measurements, a capability which is a prerequisite for reliable certification of the linewidths of features on reference …
Date: February 27, 1996
Creator: Cresswell, M. W.; Ghoshtagore, R. N.; Allen, R. A.; Linholm, L. W.; Villarrubia, J. S. & Sniegowski, J. J.
System: The UNT Digital Library