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Water flows from slotted pipes

Description: Results of experiments and analyses that determine jet flow distribution from slotted pipes of dimensions typical for OC-OTEC evaporators or condensers are described. For a pipe with a 6.3-cm inside diameter and 0.64-cm wide slot, the measured and predicted jet flow was low and nearly parallel to the pipe at the entrance, and high and perpendicular to the pipe only near the closed end. Slot lengths ranged from 1.5 m to 4.6 m, and inlet flow rates varied from 6 kg/s to 17 kg/s. Friction reduces the pressure in the entrance and intermediate portions of the pipe, while the rapidly decelerating flow produces high pressure recovery as it approaches the closed end. In the region of high flow next to the closed end, the ratio of slot area (slot length times width) to pipe cross-sectional area is less than two. To use a slotted pipe for generating falling jets in an OC-OTEC plant, the slot length should be 1 m or less (for a pipe with a 6.3-cm inside diameter and a 0.64-cm wide slot).
Date: April 1, 1981
Creator: Olson, D.A.
Partner: UNT Libraries Government Documents Department

Looking for anomalons with a segmented Cerenkov detector

Description: An experiment performed at the Lawrence Berkeley Laboratory Bevalac, Expt. 676H, to study the anomalon effect with a segmented total-internal-reflection Cerenkov detector is reported. Radiators of 3mm thick BK7W optical glass and 2mm thick fused silica and a beam of /sup 40/Ca at 2.1 GeV/nucleon were used. Results are presented and discussed.
Date: October 1, 1984
Creator: Olson, D.L.
Partner: UNT Libraries Government Documents Department

Liquid lithium corrosion research. Progress report, April 1, 1975-- December 31, 1975

Description: Kinetics for grain boundary penetration and weight loss were determined for 304L stainless steel in Ti-gettered liquid Li. Empirical weight loss rate coefficient expressions were determined as function of both N content and temperature which predict the weight loss behavior of stainless steel for Li with high N content. Capillarity was eliminated as a possible driving force for grain boundary penetration of Fe by Li with the evidence of a grain boundary groove. Coupled ionic diffusion in a corrosion product surface film is suggested as the controlling mechanism for grain boundary grooving of Fe in N-contaminated liquid Li. Stress-enhanced grain boundary penetration showed that the penetration of stressed Fe is a function of t sup 1/3 rather than t sup 1/2, suggesting that primary creep of the Fe is continually breaking the protective corrosion product in the grain boundaries. A new purification procedure and systems were designed and constructed to achieve very low N contents in the liquid Li (less than 300 ppM N). A gas purification train, based on a molten Al bubbler for the removal of O and N, was designed and built, and vacuum melting of as-received Li and gettering are being initiated. Experiments designed to determine the role of Cr in stainless steel resistance are in progress. Also experiments have been designed which will investigate how liquid metal corrosion is a function of the contact potential between the metals. (auth)
Date: January 1, 1975
Creator: Olson, D.L. & Bradley, W.L.
Partner: UNT Libraries Government Documents Department

Surveillance application using patten recognition software at the EBR-II Reactor Facility

Description: The System State Analyzer (SSA) is a software based pattern recognition system. For the past several year this system has been used at Argonne National Laboratory's Experimental Breeder Reactor 2 (EBR-2) reactor for detection of degradation and other abnormalities in plant systems. Currently there are two versions of the SSA being used at EBR-2. One version of SSA is used for daily surveillance and trending of the reactor delta-T and startups of the reactor. Another version of the SSA is the QSSA which is used to monitor individual systems of the reactor such as the Secondary Sodium System, Secondary Sodium Pumps, and Steam Generator. This system has been able to detect problems such as signals being affected by temperature variations due to a failing temperature controller.
Date: January 1, 1992
Creator: Olson, D.L.
Partner: UNT Libraries Government Documents Department

Silicon halide-alkali metal flames as a source of solar grade silicon. Third quarterly report

Description: It is proposed to determine the feasibility of using continuous flames of alkali metals and silicon halides in a large scale process to produce solar-grade silicon at low cost. Primary emphasis is being given to the reaction of Na with SiCl/sub 4/. The measurements of K or Na + SiCl/sub 4/, Na + SiHCl/sub 3/, and K or Na + SiF/sub 4/ flame spectra were completed. Construction of the scaled-up tubular flow reactor has been completed and experiments begun. Stable flames of Na + SiCl/sub 4/ diluted with H/sub 2//Ar were achieved and samples of solid product were taken from the reactor walls. Thermochemical calculations of the input conditions necessary to simulate the Westinghouse silicon process showed that we can achieve the same total enthalpy (and reaction zone temperature) by using vaporized reactants with H/sub 2//Ar heated to 1300 K. Construction of the necessary H/sub 2//Ar oven has been completed and experiments have begun.
Date: March 1, 1978
Creator: Olson, D.B. & Miller, W.J.
Partner: UNT Libraries Government Documents Department

Lithium compatibility research: status and requirements for ferrous materials

Description: A brief historical review and a description of the present status of the knowledge accumulated on lithium-ferrous alloy corrosion research are presented and discussed. The effects of various parameters are discussed and the future requirements of lithium corrosion research are presented and discussed.
Date: January 1, 1978
Creator: Selle, J.E. & Olson, D.L.
Partner: UNT Libraries Government Documents Department

Silicon halide--alkali metal flames as a source of solar grade silicon

Description: This program is designed to demonstrate the feasibility of using alkali metal-silicon halide diffusion flames to produce solar-cell-grade silicon in large quantities at low cost. Prior work has demonstrated that high purity silicon (metallic impurities < 5 ppm) can be produced using Na + SiCl/sub 4/ and Na + SiF/sub 4/ flames. Much lower flame temperatres were observed in the latter case as well as low silicon yields due to Na/sub 2/SiF/sub 6/ formation. Work performed during the current reporting period has shown that reactor wall temperaure of approximately 1000 K are sufficient to prevent formation of Na/sub 2/SiF/sub 6/. Silicon produced from SiF/sub 4/ appears identical in form and purity to that from SiCl/sub 4/ although product collection and separation are less thermo-chemically favored in the fluoride system. To separate the silicon from the byproduct salt in an efficient and continuous manner, higher temeratures are necessary. Resistively heated thin-walled graphite tubular reactors have been used to achieve these temperatures (> 1700 K), and successful product separation has been experimentally demonstrated using a Na + SiCl/sub 4/ flame. Keys to this success appear to be sustaining high reaction temperatures and not using a diluent gas in the recent flows.
Date: October 1, 1978
Creator: Olson, D.B. & Miller, W.J.
Partner: UNT Libraries Government Documents Department

Silicon halide-alkali metal flames as a source of solar grade silicon. Seventh quarterly report

Description: This program is aimed at determining the feasibility of using high temperature reactions of alkali metals and silicon halides to produce low cost solar-grade silicon. Experiments are being performed to evaluate product separation and collection processes, measure heat release parameters for scaling purposes, and determine the effects of the reactants and/or products on materials of reactor construction. Prior work has demonstrated continuous separation of silicon from the byproduct alkali salt at a production rate of 0.5 kg h/sup -1/ in a graphite reactor using the reaction of Na with SiCl/sub 4/. Silicon of similar purity is obtained from Na + SiF/sub 4/ flames although yields are lower and product separation and collection are less thermochemically favored. During the current reporting period the results of heat release experiments have been used to design and construct a new type of thick-walled graphite reactor to produce larger quantities of silicon. A new reactor test facility has been constructed. Material compatibility tests have been performed for NA in contact with graphite and several coated graphites. All samples were rapidly degraded at T = 1200 K, while samples retained structural strength at 1700 K. Pyrolytic graphite coatings cracked and separated from substrates in all cases.
Date: April 1, 1979
Creator: Olson, D.B. & Gould, R.K.
Partner: UNT Libraries Government Documents Department

Silicon halide--alkali metal flames as a source of solar grade silicon. Fourth quarterly report, March 1--May 31, 1978

Description: This program is designed to demonstrate the feasibility of using alkali metal-silicon halide diffusion flames in a process for producing large quantities of solar cell grade silicon at low cost. Na + SiCl/sub 4/ flow tube experiments were completed under a variety of conditions of pressure, reactor temperature, and flow velocity. Comparative experiments using 300 K Ar and 1000 K H/sub 2//Ar diluents were performed with few differences in deposition rates or product characteristics found. Silicon from both sets of experiments was found to contain small amounts of Fe and other metal impurities. A Na + SiF/sub 4/ experiment, run in an unheated reactor tube, was found to produce a large fraction of Na/sub 2/SiF/sub 6/, with only a small yield of Si.
Date: June 1, 1978
Creator: Olson, D.B. & Miller, W.J.
Partner: UNT Libraries Government Documents Department

Organic Based Nanocomposite Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-04-145

Description: This CRADA will focus on the development of organic-based solar cells. Key interfacial issues in these cells will be investigated. In this rapidly emerging technology, it is increasingly clear that cell architecture will need to be at the nanoscale and the interfacial issues between organic elements (small molecule and polymer), transparent conducting oxides, and contact metallizations are critical. Thus this work will focus on the development of high surface area and nanostructured nanocarpets of inorganic oxides, the development of appropriate surface binding/acceptor molecules for the inorganic/organic interface, and the development of next-generation organic materials. Work will be performed in all three areas jointly at NREL and Konarka (with their partner in the third area of the University of Delaware). Results should be more rapid progress toward cheap large-area photovoltaic cells.
Date: January 1, 2013
Creator: Olson, D.
Partner: UNT Libraries Government Documents Department

Novel concepts in weld metal science: Role of gradients and composite structure

Description: The effects of compositional and microstructural gradients on weld metal properties are being investigated. Crack propagation is solidified alloy structures is being characterized as to solidification orientation and the profile of the compositional variations. The effects of compositional gradients, are considered based on a thermodynamic analysis, referred to as the Cahn-Hillard analysis, which describes the degree to which a local surface energy is modified by the presence of a compositional gradient. The analysis predicts that both ductile and brittle fracture mechanisms are enhanced by the presence of a composition gradient. Special techniques to produce laboratory samples with microstructures which simulate the composition and microstructure gradients in solidified weld metal are used, along with appropriate mathematical models, to evaluate the properties of the composite weld metals. The composite modeling techniques are being applied to describe the effects of compositional and microstructural gradients on weld metal properties in Ni-Cu alloys. The development of metal matrix composition weld deposits on austenitic stainless steels has been studied. The particulate metal matrix composites were produced with ceramic or refractory metal powder filled cored wire, which was gas tungsten arc and gas metal arc welded.
Date: December 1, 1991
Creator: Matlock, D.K. & Olson, D.L.
Partner: UNT Libraries Government Documents Department

A system safety approach to the FAA surveillance process

Description: As commercial air travel grows in terms of the number of passenger miles flown, there is expected to be a corresponding dramatic increase in the absolute number of accidents. This despite an enviable safety record and a very low accident rate. The political environment is such that an increase in the absolute number of accidents is not acceptable, with a stated goal of a factor of five reduction in the aviation fatal accident rate within ten years. The objective of this project is to develop an improved surveillance process that will provide measurements of the current state-of-health and predictions of future state of health of aircraft, operators, facilities, and personnel. Methodologies developed for nuclear weapon safety, in addition to more well known system safety and high-consequence engineering techniques, will be used in this approach.
Date: August 8, 1997
Creator: Werner, P.W. & Olson, D.R.
Partner: UNT Libraries Government Documents Department

Open-cycle OTEC system performance analysis. [Claude cycle]

Description: An algorithm developed to calculate the performance of Claude-Cycle ocean thermal energy conversion (OTEC) systems is described. The algorithm treats each component of the system separately and then interfaces them to form a complete system, allowing a component to be changed without changing the rest of the algorithm. Two components that are subject to change are the evaporator and condenser. For this study we developed mathematical models of a channel-flow evaporator and both a horizontal jet and spray director contact condenser. The algorithm was then programmed to run on SERI's CDC 7600 computer and used to calculate the effect on performance of deaerating the warm and cold water streams before entering the evaporator and condenser, respectively. This study indicates that there is no advantage to removing air from these streams compared with removing the air from the condenser.
Date: October 1, 1980
Creator: Lewandowski, A.A.; Olson, D.A. & Johnson, D.H.
Partner: UNT Libraries Government Documents Department

Thin film reactions on alloy semiconductor substrates

Description: The interactions between Pt and In{sub .53}Ga{sub .47}As have been studied. In{sub .53}Ga{sub .47}As substrates with 70nm Pt films were encapsulated in SiO{sub 2}, and annealed up to 600{degree}C in flowing forming gas. The composition and morphology of the reaction product phases were studied using x-ray diffraction, Auger depth profiling, and transmission electron microscopy. The reaction kinetics were examined with Rutherford Backscattering. Results show that Pt/In{sub .53}Ga{sub .47}As reacts to form many of the reaction products encountered in the Pt/GaAs and Pt/InP reactions: PtGa, Pt{sub 3}Ga, and PtAs{sub 2}. In addition, a ternary phase, Pt(In:Ga){sub 2}, develops, which is a solid solution between PtIn{sub 2} and PtGa{sub 2}. The amount of Ga in the ternary phase increases with annealing temperature, which causes a decrease in the lattice parameter of the phase. The reaction products show a tendency to form layered structures, especially for higher temperatures and longer annealing times. Unlike the binary case, the PtAs{sub 2}, phase is randomly oriented on the substrate, and is intermingle with a significant amount of Pt(In:Ga){sub 2}. Following Pt/In{sub .53}Ga{sub .47}As reactions, two orientation relationships between the Pt(In:Ga){sub 2} product phase and the substrate were observed, despite the large mismatch with the substrate ({approximately}8%). For many metal/compound semiconductor interactions, the reaction rate is diffusion limited, i.e. exhibits a parabolic dependence on time. An additional result of this study was the development of an In-rich layer beneath the reacted layer. The Auger depth profile showed a substantial increase in the sample at this layer. This is a significant result for the production of ohmic contacts, as the Schottky barrier height in this system lower for higher In concentrations. 216 refs.
Date: November 1, 1990
Creator: Olson, D.A.
Partner: UNT Libraries Government Documents Department

Silicon halide-alkali metal flames as a source of solar grade silicon. Final report

Description: The object of this program was to determine the feasibility of using continuous high-temperature reactions of alkali metals and silicon halides to produce silicon in large quantities and of suitable purity for use in the production of photovoltaic solar cells. Equilibrium calculations showed that a range of conditions were available where silicon was produced as a condensed phase but the byproduct alkali metal salt was a vapor. A process was proposed using the vapor phase reaction of Na with SiCl/sub 4/. Low pressure experiments were performed demonstrating that free silicon was produced and providing experience with the construction of reactant vapor generators. Further experiments at higher reagent flow rates were performed in a low temperature flow tube configuration with co-axial injection of reagents. Relatively pure silicon was produced in these experiments. A high temperature graphite flow tube was built and continuous separation of Si from NaCl was demonstrated. A larger-scaled well-stirred reactor was built. Experiments were performed to investigate the compatibility of graphite-based reactor materials of construction with sodium. At 1100 to 1200 K none of these materials were found to be suitable. At 1700 K the graphites performed well with little damage except to coatings of pyrolytic graphite and silicon carbide which were damaged.
Date: January 1, 1980
Creator: Olson, D.B.; Miller, W.J. & Gould, R.K.
Partner: UNT Libraries Government Documents Department