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On-chip IR spectral sensors by superconducting detector arrays. Semiannual report {number_sign} 2, 18 January 1995--18 July 1995

Description: The overall objective of Phase 2 is to bring this new spectrometer-on-a-chip technology concept to a sufficiently mature stage of development that it can attract commercial support and be carried to market. The specific technical missions of the Phase 2 program are those for the Project Tasks listed below. These mission objectives are: (1) to establish and prove-out the fabrication processing of silicon wafers into arrays of interference-filter plates; (2) to demonstrate that the linear-array HTS detector technology can be scaled up into square arrays of sufficient size and performance to meet the design requirements developed in the Phase 1 effort; (3) to expand the view of the technology so as to see it in a full engineering-systems context, and thus ensure that at the earliest stage possible conflicts can be resolved, thus a systems design can be accomplished that will realistically encompass all the interacting components; (4) to demonstrate, by fabrication and testing, that the components in this systems design can be combined and will deliver the functionality (e.g., spectral region, bandwidth, and resolution) predicted by the design, and in the context of one or two simple emission-line-spectroscopy prototype applications; (5) to identify and resolve conflicts in the design and fabrication methods/processes such that the new spectrometer can meet the desired goal of multiple applications potential. A brief description of each of these 5 tasks is given along with the progress made on each.
Date: September 29, 1995
Creator: Fenner, D.B.; Carangelo, R.M. & Kung, P.J.
Partner: UNT Libraries Government Documents Department

Compression ratio effect on methane HCCI combustion

Description: We have used the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to simulate HCCI (homogeneous charge compression ignition) combustion of methane-air mixtures. HCT is applied to explore the ignition timing, bum duration, NO<sub>x</sub> production, gross indicated efficiency and gross IMEP of a supercharged engine (3 atm. Intake pressure) with 14:1, 16:l and 18:1 compression ratios at 1200 rpm. HCT has been modified to incorporate the effect of heat transfer and to calculate the temperature that results from mixing the recycled exhaust with the fresh mixture. This study uses a single control volume reaction zone that varies as a function of crank angle. The ignition process is controlled by adjusting the intake equivalence ratio and the residual gas trapping (RGT). RGT is internal exhaust gas recirculation which recycles both thermal energy and combustion product species. Adjustment of equivalence ratio and RGT is accomplished by varying the timing of the exhaust valve closure in either 2-stroke or 4-stroke engines. Inlet manifold temperature is held constant at 300 K. Results show that, for each compression ratio, there is a range of operational conditions that show promise of achieving the control necessary to vary power output while keeping indicated efficiency above 50% and NO<sub>x</sub> levels below 100 ppm. HCT results are also compared with a set of recent experimental data for natural gas.
Date: September 29, 1998
Creator: Aceves, S. M.; Pitz, W.; Smith, J. R. & Westbrook, C.
Partner: UNT Libraries Government Documents Department

Evaluation of nitrate and nitrite destruction/separation technologies

Description: This report describes and evaluates four types of nitrate and nitrite destruction and separation technologies that could be used to treat the aqueous, alkaline, nitrate-bearing mixed waste that is generated by the In-Tank Precipitation (ITP) process at the Savannah River Site (SRS). The technologies considered in this report include thermal, hydrothermal, chemical, and electrochemical technologies.
Date: August 29, 1997
Creator: Hobbs, D.T.
Partner: UNT Libraries Government Documents Department

Successful integration of pollution prevention strategies during deactivation and decommissioning of chemistry R{ampersand}D facilities

Description: The Chemistry & Materials Sciences (C&MS) Directorate is in the third year of a four-year space consolidation plan. In 1994, approximately half of the total directorate square footage was comprised of 40-year old wet chemistry research buildings that had exceeded their useful life and were viewed a legacy facilities to the program. This mix of old vs. new laboratory space was not properly aligned nor suited for future needs of C&MS, from both the cultural or economic position, thus change was needed. C&MS instituted an aggressive, strategic, business-driven space consolidation initiative, called SAT (Space Action Team), to optimize space utilization, reduce annual costs, meet strategic program needs, and consolidate activities by functional area. The plan called for a 4-year process beginning in FY95 to realign the directorate`s facility portfolio through relocations, consolidations, transfer of facility ownership, demolition of trailers and new construction with a 20% sq/ft reduction as an end goal. As with all business driven initiatives, existing operating costs, implementation costs, cost avoidance and future operating costs were key metrics to measure against the strategic goal. Where P2 was not an essential element in the strategic planning process, it played a key role in the continuing success of the process. SAT is in year three of the four year plan (approximate $5 million investment), which has made a major contribution to the success of C&MS by achieving the directorate`s goals of improving the utilization of space by 30%, increasing quality of the facilities, and reducing annual operating costs. To date, SAT has achieved an on-going organizational facility charge saving of $2 million /year, minimized Program downtime, transferred 120,000 sq ft to new owners, relocated 86 labs, vacated 9 buildings, deactivate, decommissioned and decontaminated four 40 plus year old R&D facilities, and demolished 9 trailers with no incidents or injuries. ...
Date: August 29, 1997
Creator: Burgin, C. D. & Waterman, M. A.
Partner: UNT Libraries Government Documents Department

Ferrocyanide safety program: Final report on adiabatic calorimetry and tube propagation tests with synthetic ferrocyanide materials

Description: Based on Fauske and Associates, Inc. Reactive System Screening Tool tests, the onset or initiation temperature for a ferrocyanide-nitrate propagating reaction is about 250 degrees Celcius. This is at about 200 degrees Celcius higher than current waste temperatures in the highest temperature ferrocyanide tanks. Furthermore, for current ambient waste temperatures, the tube propagation tests show that a ferrocyanide concentration of 15.5 wt% or more is required to sustain a propagation reaction in the complete absence of free water. Ignoring the presence of free water, this finding rules out propagating reactions for all the Hanford flowsheet materials with the exception of the ferrocyanide waste produced by the original In Farm flowsheet
Date: September 29, 1995
Creator: Fauske, H.F.; Meacham, J.E. & Cash, R.J.
Partner: UNT Libraries Government Documents Department

Volatiles combustion in fluidized beds. Final technical report, 4 September 1992--4 June 1995

Description: The goal of this project is to investigate the conditions in which volatiles will burn within both the dense and freeboard regions of fluidized beds. Experiments using a fluidized bed operated at incipient fluidization are being conducted to characterize the effect of particle surface area, initial fuel concentration, and particle type on the inhibition of volatiles within a fluidized bed. A review of the work conducted under this grant is presented in this Final Technical Report. Both experimental and theoretical work have been conducted to examine the inhibition of the combustion by the fluidized bed material, sand. It has been shown that particulate phase at incipient fluidization inhibits the combustion of propane by free radical destruction at the surface of sand particles within the particulate phase. The implications of these findings is that at bed temperatures lower than the critical temperatures, gas combustion can only occur in the bubble phase or at the top surface of a bubbling fluidized bed. In modeling fluidized bed combustion this inhibition by the particulate phase should be included.
Date: February 29, 1996
Creator: Pendergrass, R.A. II; Raffensperger, C. & Hesketh, R.P.
Partner: UNT Libraries Government Documents Department

Demonstration of a vapor density monitoring system using UV radiation generated from quasi-phasematched SHG waveguide devices

Description: Many industrial applications require non-intrusive diagnostics for process monitoring and control. One example is the physical vapor deposition of titanium alloys. In this paper we present a system based on laser absorption spectroscopy for monitoring titanium vapor. Appropriate transitions for monitoring high rate vaporization of titanium require extension of available IR diode technology to the UV. The heart of this vapor density monitoring system is the 390nm radiation generated from quasi-phase matched interactions within periodically poled waveguides. In this paper, key system components of a UV laser absorption spectroscopy based system specific for titanium density monitoring are described. Analysis is presented showing the minimum power levels necessary from the ultraviolet laser source. Performance data for prototype systems using second harmonic generation (SHG) waveguide technology is presented. Application of this technology to other alloy density monitoring systems is discussed.
Date: January 29, 1996
Creator: Galanti, S. A.; Berzins, L. V.; Brown, J. B.; Tamosaitis, R. S.; Bortz, M. L.; Day, T. et al.
Partner: UNT Libraries Government Documents Department

A new method for measuring the dynamic surface tension of complex-mixture liquid drops

Description: A simple and accurate technique has been developed for measuring dynamic surface tension. The new technique is based on growing a drop at the end of a fine capillary into another immiscible fluid and can follow the changes in tension at a freshly formed interface during its entire period of evolution. When the relative importance of the surface tension force is large compared to gravitational and viscous forces, shapes of growing drops are sections of spheres and the difference in pressure between the interior and the exterior of the drop {triangle}p is related to the surface tension {sigma} and the radius of curvature R by the static Young-Laplace formula {triangle}p = 2{sigma}/R. In contrast to related work, the new technique can determine the surface tension of an interface with a surface age of a few to tens of milliseconds by measuring transient drop shapes and pressures in 1/6 to 1 millisecond. The capabilities of the new method are demonstrated by performing tension measurements on liquid systems that do not exhibit dynamic surface tension as well as ones that exhibit significant dynamic tension effects. Tension measurements made with surfactant-laden solutions show that variation of surface tension is nonmonotonic in time. In such systems, the dynamic behavior of surface tension is shown to depend upon both the rate of interfacial dilatation and that of surfactant transport. A maximum in the surface tension is attained when the lowering of the surfactant concentration on the drop interface due to its dilatation is balanced by the addition of fresh surfactant to the interface by convection and diffusion.
Date: June 29, 1994
Creator: Zhang, X.; Harris, M.T. & Basaran, O.A.
Partner: UNT Libraries Government Documents Department

Measurement of Individual Aileron Hinge Moments and Aileron Control Characteristics of a P-40F Airplane

Description: "Flight measurements have been made of the individual aileron hinge moments, aileron rolling effectiveness pb/2V ,and stick-force characteristics in abrupt aileron rolls with a P-40F airplane (AAF No. 41-14119) over an indicated airspeed range from 108 to 304 miles per hour. Three methods for measuring the rate of change of hinge moment with angle of attack were investigated. Presented for comparison with the flight results are data from two-dimensional wind-tunnel tests of the wing-aileron profile as measured at the center aileron hinge" (p. 1).
Date: January 29, 1945
Creator: Goranson, R. Fabian
Partner: UNT Libraries Government Documents Department

Passive gas separator and accumulator device

Description: A separation device employing a gas separation filter and swirler vanes for separating gas from a gas-liquid mixture is provided. The cylindrical filter uses the principle that surface tension in the filter pores prevents gas bubbles from passing through; the gas collects in the interior of the filter to form larger bubbles in the center of the device. The device is suited for microgravity since the swirlers induce a centrifugal force which forces liquid from the inner region through the pores and the device outlet while the entrained gas is trapped by the filter. The device includes a cylindrical gas storage screen enclosed by the filter. The screen has pores larger than those of the filters. The screen prevents larger bubbles that have been formed from reaching and interfering with the pores of the filter. The device is initially filled with a gas other than that which is to be separated; this results in separation of the gas even before gas bubbles are present in the mixture. Initially filling the device with the dissimilar gas and preventing the gas from escaping before operation can be accomplished by sealing the dissimilar gas in the inner region with a ruptured disc which can be ruptured when the device is activated for use.
Date: November 29, 1993
Creator: Choe, Hwang & Fallas, T.T.
Partner: UNT Libraries Government Documents Department