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Sample records for anechoic chamber facility

  1. An anechoic chamber facility for investigating aerodynamic noise

    NASA Technical Reports Server (NTRS)

    Massier, P. F.; Parthasarathy, S. P.

    1972-01-01

    The aerodynamic noise facility was designed to be used primarily for investigating the noise-generating mechanisms of high-temperature supersonic and subsonic jets. The facility consists of an anechoic chamber, an exhaust jet silencer, instrumentation equipment, and an air heater with associated fuel and cooling systems. Compressed air, when needed for jet noise studies, is provided by the wind tunnel compressor facility on a continuous basis. The chamber is 8.1 m long, 5.0 m wide, and 3.0 m high. Provisions have been made for allowing outside air to be drawn into the anechoic chamber in order to replenish the air that is entrained by the jet as it flows through the chamber. Also, openings are provided in the walls and in the ceiling for the purpose of acquiring optical measurements. Calibration of the chamber for noise reflections from the wall was accomplished in octave bands between 31.2 Hz and 32 kHz.

  2. Almond test body. [for microwave anechoic chambers

    NASA Technical Reports Server (NTRS)

    Dominek, Allen K. (Inventor); Wood, Richard M. (Inventor); Gilreath, Melvin C. (Inventor)

    1989-01-01

    The invention is an almond shaped test body for use in measuring the performance characteristics of microwave anechoic chambers and for use as a support for components undergoing radar cross-section measurements. The novel aspect of this invention is its shape, which produces a large dynamic scattered field over large angular regions making the almond valuable for verifying the performance of microwave anechoic chambers. As a component mount, the almond exhibits a low return that does not perturb the measurement of the component and it simulates the backscatter characteristics of the component as if over an infinite ground plane.

  3. Tests of anechoic chamber for aeroacoustics investigations

    NASA Astrophysics Data System (ADS)

    Palchikovskiy, V. V.; Bersenev, Yu. V.; Makashov, S. Yu.; Belyaev, I. V.; Korin, I. A.; Sorokin, E. V.; Khramtsov, I. V.; Kustov, O. Yu.

    2016-10-01

    The paper presents the results of qualification tests in the new anechoic chamber of Perm National Research Polytechnic University (PNRPU) built in 2014-2015 and evaluation of the chamber quality in aeroacoustic experiments. It describes design features of the chamber and its sound-absorption lining. The qualification tests were carried out with tonal and broadband noise sources in the frequency range 100 Hz - 20 kHz for two different cases of the source arrangement. In every case, measurements were performed in three directions by traverse microphones. Qualification tests have determined that in the chamber there is a free acoustic field within radius of 2 m for tonal noise and 3 m for broadband noise. There was also evaluated acoustic quality of the chamber by measurements of the jet noise and vortex ring noise. The results of the experiments demonstrate that PNRPU anechoic chamber allows the aeroacoustic measurements to be performed to obtain quantitative results.

  4. Anechoic chamber in industrial plants. [construction materials and structural design

    NASA Technical Reports Server (NTRS)

    Halpert, E.; Juncu, O.; Lorian, R.; Marfievici, D.; Mararu, I.

    1974-01-01

    A light anechoic chamber for routine acoustical measurements in the machine building industry is reported. The outer housing of the chamber consists of modules cast in glass fiber reinforced polyester resin; the inner housing consists of pyramidal modules cut out of sound absorbing slates. The parameters of this anechoic chamber facilitate acoustical measurements according to ISO and CAEM recommendations.

  5. Anechoic Chambers: Aerospace Applications. (Latest Citations from the Aerospace Database)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The bibliography contains citations concerning the design, development, performance, and applications of anechoic chambers in the aerospace industry. Anechoic chamber testing equipment, techniques for evaluation of aerodynamic noise, microwave and radio antennas, and other acoustic measurement devices are considered. Shock wave studies on aircraft models and components, electromagnetic measurements, jet flow studies, and antenna radiation pattern measurements for industrial and military aerospace equipment are discussed. (Contains 50-250 citations and includes a subject term index and title list.)

  6. Anechoic Chambers: Aerospace Applications. (Latest Citations from the Aerospace Database)

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The bibliography contains citations concerning the design, development, performance, and applications of anechoic chambers in the aerospace industry. Anechoic chamber testing equipment, techniques for evaluation of aerodynamic noise, microwave and radio antennas, and other acoustic measurement devices are considered. Shock wave studies on aircraft models and components, electromagnetic measurements, jet flow studies, and antenna radiation pattern measurements for industrial and military aerospace equipment are discussed. (Contains 50-250 citations and includes a subject term index and title list.)

  7. Characteristics of an anechoic chamber for fan noise testing

    NASA Technical Reports Server (NTRS)

    Wuzyniak, J. A.; Shaw, L. M.; Essary, J. D.

    1977-01-01

    Acoustical and mechanical design features of NASA Lewis Research Center's engine fan noise facility are described. Acoustic evaluation of the chamber, which is lined with an array of stepped wedges, is described. Results from the evaluation in terms of cut-off frequency and non-anechoic areas near the walls are detailed. Fan models are electrically driven to 20,600 RPM in either the inlet mode or exhaust mode to facilitate study of both fore and aft fan noise. Inlet noise characteristics of the first fan tested are discussed and compared to full-scale levels. Turbulence properties of the inlet flow and acoustic results are compared with and without a turbulence reducing screen over the fan inlet.

  8. Experimental investigation of sound absorption of acoustic wedges for anechoic chambers

    NASA Astrophysics Data System (ADS)

    Belyaev, I. V.; Golubev, A. Yu.; Zverev, A. Ya.; Makashov, S. Yu.; Palchikovskiy, V. V.; Sobolev, A. F.; Chernykh, V. V.

    2015-09-01

    The results of measuring the sound absorption by acoustic wedges, which were performed in AC-3 and AC-11 reverberation chambers at the Central Aerohydrodynamic Institute (TsAGI), are presented. Wedges of different densities manufactured from superfine basaltic and thin mineral fibers were investigated. The results of tests of these wedges were compared to the sound absorption of wedges of the operating AC-2 anechoic facility at TsAGI. It is shown that basaltic-fiber wedges have better sound-absorption characteristics than the investigated analogs and can be recommended for facing anechoic facilities under construction.

  9. Design and characterization of an anechoic aeroacoustic facility

    NASA Astrophysics Data System (ADS)

    Mathew, Jose; Bahr, Chris; Carroll, Bruce; Sheplak, Mark; Cattafesta, Lou

    2005-09-01

    The design and characterization of an anechoic wind tunnel facility at the University of Florida are presented. A previously existing and ISO 3745 validated 100-Hz anechoic chamber is upgraded to incorporate an open-jet anechoic wind tunnel facility suitable for airframe noise studies, including swept-wing trailing edge studies. For suitable modeling of landing conditions, a chord-based Reynolds number of 3 to 4 million is required. The wind tunnel is driven by a 224-kW centrifugal fan controlled by a variable frequency drive. The test section measures 0.74 m (29) by 1.12 m (44) by 1.83 m (6 ft). The estimated maximum velocity attainable in the test section is ~ 76 m/s (250 ft/s). Preliminary measurements at 17 m/s indicate excellent flow uniformity and a turbulence intensity of 0.11%. Background noise level measurements with an empty test section reveal an overall SPL from 100 Hz 20 kHz of 49.9 dB, with a peak 1/3 octave-band level of 46 dB at 100 Hz that decreases to 29.9 dB at 1 kHz. Facility characterization experiments over a range of test section speeds are also reported, along with the results of preliminary trailing edge noise experiments.

  10. On the acoustic wedge design and simulation of anechoic chamber

    NASA Astrophysics Data System (ADS)

    Jiang, Changyong; Zhang, Shangyu; Huang, Lixi

    2016-10-01

    This study proposes an alternative to the classic wedge design for anechoic chambers, which is the uniform-then-gradient, flat-wall (UGFW) structure. The working mechanisms of the proposed structure and the traditional wedge are analyzed. It is found that their absorption patterns are different. The parameters of both structures are optimized for achieving minimum absorber depth, under the condition of absorbing 99% of normal incident sound energy. It is found that, the UGFW structure achieves a smaller total depth for the cut-off frequencies ranging from 100 Hz to 250 Hz. This paper also proposes a modification for the complex source image (CSI) model for the empirical simulation of anechoic chambers, originally proposed by Bonfiglio et al. [J. Acoust. Soc. Am. 134 (1), 285-291 (2013)]. The modified CSI model considers the non-locally reactive effect of absorbers at oblique incidence, and the improvement is verified by a full, finite-element simulation of a small chamber. With the modified CSI model, the performance of both decorations with the optimized parameters in a large chamber is simulated. The simulation results are analyzed and checked against the tolerance of 1.5 dB deviation from the inverse square law, stipulated in the ISO standard 3745(2003). In terms of the total decoration depth and anechoic chamber performance, the UGFW structure is better than the classic wedge design.

  11. Analysis of Anechoic Chamber Testing of the Hurricane Imaging Radiometer

    NASA Technical Reports Server (NTRS)

    Fenigstein, David; Ruf, Chris; James, Mark; Simmons, David; Miller, Timothy; Buckley, Courtney

    2010-01-01

    The Hurricane Imaging Radiometer System (HIRAD) is a new airborne passive microwave remote sensor developed to observe hurricanes. HIRAD incorporates synthetic thinned array radiometry technology, which use Fourier synthesis to reconstruct images from an array of correlated antenna elements. The HIRAD system response to a point emitter has been measured in an anechoic chamber. With this data, a Fourier inversion image reconstruction algorithm has been developed. Performance analysis of the apparatus is presented, along with an overview of the image reconstruction algorithm

  12. The New Anechoic Shielded Chambers Designed for Space and Commercial Applications at LIT

    NASA Technical Reports Server (NTRS)

    da Silva, Benjamim; Galvao, M. C.; Pereira, Clovis Solano

    2008-01-01

    The main objective of this paper is to present the capabilities of the new anechoic shielded rooms designed for space and commercial applications as part of the Integration and Testing Laboratory (LIT, Laboratorio de Integracao e Testes) in Brazil. A new anechoic shielded room named CBA2 has been in full operation since March 2007 and a remodeled chamber CBA1 is planned to be ready by the end of 2008, replacing an old facility which was in operation for the last 18 years. The Brazilian Space Program started with very small and simple satellites and the old CBA1 chamber was conceived in 1987 to accomplish the EMI/EMC tests not requiring significant volumes. Since the very beginning this facility was also used by the private sector for other applications mainly due to the absorption of digital electronics in all kind of products. The intense use of this facility during the last years, operating three shifts a day, caused a normal degradation and imposed several limitations. Therefore, a new totally remodeled chamber was designed considering the state of the art in terms of absorbers and associated instrumentation. On the other hand the facility CBA2 was conceived, designed and implemented to test large satellites taking into account the advance of the technology in terms of RF frequencies, power level, testing methodologies and several other factors. A very interesting and unique aspect of this project was the partnership between the private sector and governmental institution. As a result, the total investment was shared between several companies and consequently a time-sharing use of the facility as well.

  13. Inlet noise on 0.5-meter-diameter NASA QF-1 fan as measured in an unmodified compressor aerodynamic test facility and in an anechoic chamber

    NASA Technical Reports Server (NTRS)

    Gelder, T. F.; Soltis, R. F.

    1975-01-01

    Narrowband analysis revealed grossly similar sound pressure level spectra in each facility. Blade passing frequency (BPF) noise and multiple pure tone (MPT) noise were superimposed on a broadband (BB) base noise. From one-third octave bandwidth sound power analyses the BPF noise (harmonics combined), and the MPT noise (harmonics combined, excepting BPF's) agreed between facilities within 1.5 db or less over the range of speeds and flows tested. Detailed noise and aerodynamic performance is also presented.

  14. Design and analysis of a hemi-anechoic chamber at Michigan Technological University

    NASA Astrophysics Data System (ADS)

    Dreyer, Jason; Jangale, Ashish; Rao, Mohan D.

    2005-09-01

    A four-wheel chassis roll dynamometer test facility was installed on the campus of Michigan Technological University (MTU). The chassis dynamometer was enclosed in a soundproof hem-anechoic room in order to conduct noise radiation measurements on test vehicles. All surfaces of the room, except the floor and control room window, were acoustically treated with donated tetrahedral acoustic cones and panels. The acoustic absorption properties of these materials were characterized through reverberation chamber and impedance tube testing, and the effects of air gaps, cone orientation, and cone mounting materials were qualitatively evaluated. The design of the wall, ceiling, and door treatments of the chamber was based on the sound absorption properties of these materials, in addition to spatial constraints and cost considerations. The treated chamber acoustics were predicted based on the amount of acoustic material that could be applied to given chamber dimensions and would still preserve the functionality of the room. These predictions were validated through evaluation of the actual room treatment based on average reverberation time at 100-Hz third-octave band, free sound field characteristic 6-dB reduction in sound pressure level (SPL) per doubling in distance from source, noise reduction at the chamber boundaries, and background SPL Noise Criteria (NC) Rating.

  15. A two dimensional finite difference time domain analysis of the quiet zone fields of an anechoic chamber

    NASA Technical Reports Server (NTRS)

    Ryan, Deirdre A.; Luebbers, Raymond J.; Nguyen, Truong X.; Kunz, Karl S.; Steich, David J.

    1992-01-01

    Prediction of anechoic chamber performance is a difficult problem. Electromagnetic anechoic chambers exist for a wide range of frequencies but are typically very large when measured in wavelengths. Three dimensional finite difference time domain (FDTD) modeling of anechoic chambers is possible with current computers but at frequencies lower than most chamber design frequencies. However, two dimensional FDTD (2D-FTD) modeling enables much greater detail at higher frequencies and offers significant insight into compact anechoic chamber design and performance. A major subsystem of an anechoic chamber for which computational electromagnetic analyses exist is the reflector. First, an analysis of the quiet zone fields of a low frequency anechoic chamber produced by a uniform source and a reflector in two dimensions using the FDTD method is presented. The 2D-FDTD results are compared with results from a three dimensional corrected physical optics calculation and show good agreement. Next, a directional source is substituted for the uniform radiator. Finally, a two dimensional anechoic chamber geometry, including absorbing materials, is considered, and the 2D-FDTD results for these geometries appear reasonable.

  16. Reduction of fan noise in an anechoic chamber by reducing chamber wall induced inlet flow disturbances

    NASA Technical Reports Server (NTRS)

    Dittmar, J. H.; Mackinnon, M. J.; Woodward, R. P.

    1978-01-01

    The difference between the flight and ground static noise of turbofan engines presents a significant problem in engine noise testing. The additional noise for static testing has been attributed to inlet flow disturbances or turbulence interacting with the fan rotor. In an attempt to determine a possible source of inflow disturbances entering fans tested in the Lewis Research Center anechoic chamber, the inflow field was studied using potential flow analysis. These potential flow calculations indicated that there was substantial flow over the wall directly behind the fan inlet that could produce significant inflow disturbances. Fan noise tests were run with various extensions added to the fan inlet to move the inlet away from this backwall and thereby reduce the inlet flow disturbances. Significant noise reductions were observed with increased inlet length. Over 5 db reduction of the blade passage tone sound power level was observed between the shortest and longest inlets at 90% fan speed and the first overtone was reduced 9 db. High frequency broadband noise was also reduced.

  17. A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber

    SciTech Connect

    Chiang, W. Y.; Wu, M. H.; Wu, K. L.; Lin, M. H.; Teng, H. H.; Barnett, L. R.; Chu, K. R.; Tsai, Y. F.; Ko, C. C.; Yang, E. C.; Jiang, J. A.

    2014-08-15

    Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.

  18. A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber.

    PubMed

    Chiang, W Y; Wu, M H; Wu, K L; Lin, M H; Teng, H H; Tsai, Y F; Ko, C C; Yang, E C; Jiang, J A; Barnett, L R; Chu, K R

    2014-08-01

    Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.

  19. A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber

    NASA Astrophysics Data System (ADS)

    Chiang, W. Y.; Wu, M. H.; Wu, K. L.; Lin, M. H.; Teng, H. H.; Tsai, Y. F.; Ko, C. C.; Yang, E. C.; Jiang, J. A.; Barnett, L. R.; Chu, K. R.

    2014-08-01

    Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.

  20. ATS 6 EMI field measurements techniques and results. [anechoic chamber scale model testing

    NASA Technical Reports Server (NTRS)

    Afifi, M. S.; Keiser, B. E.

    1974-01-01

    At the present time 'Applications Technology Satellite (ATS)-6' is the world's largest communication satellite. It handles telecommunications in the frequency range of 40 - 30,000 MHz. Power levels on board the spacecraft range from -110 dBm to 52.5 dBw. Consequently considerable care was required in the design and test of this spacecraft, in order to provide assurances that the spacecraft would perform properly in its own RF environments. The testing was performed first by placing the earth viewing module (EVM) in a specially constructed 'small' anechoic chamber with an overhead parabolic reflector section, of 8' in diameter, instead of the 30' reflector of the full scale design. The near field analysis of this paper proves that this test configuration leads to a desirable overtest for the spacecraft. The test requirements, procedure and results are also explained.

  1. Supervised Self-Organizing Classification of Superresolution ISAR Images: An Anechoic Chamber Experiment

    NASA Astrophysics Data System (ADS)

    Radoi, Emanuel; Quinquis, André; Totir, Felix

    2006-12-01

    The problem of the automatic classification of superresolution ISAR images is addressed in the paper. We describe an anechoic chamber experiment involving ten-scale-reduced aircraft models. The radar images of these targets are reconstructed using MUSIC-2D (multiple signal classification) method coupled with two additional processing steps: phase unwrapping and symmetry enhancement. A feature vector is then proposed including Fourier descriptors and moment invariants, which are calculated from the target shape and the scattering center distribution extracted from each reconstructed image. The classification is finally performed by a new self-organizing neural network called SART (supervised ART), which is compared to two standard classifiers, MLP (multilayer perceptron) and fuzzy KNN ([InlineEquation not available: see fulltext.] nearest neighbors). While the classification accuracy is similar, SART is shown to outperform the two other classifiers in terms of training speed and classification speed, especially for large databases. It is also easier to use since it does not require any input parameter related to its structure.

  2. Calibration of the Ames Anechoic Facility. Phase 1: Short range plan

    NASA Technical Reports Server (NTRS)

    Hickey, D.; Soderman, P. T.; Karamcheti, K.; Koutsoyannis, S. P.; Hopkins, R.; Mclachlan, B.

    1980-01-01

    A calibration was made of the acoustic and aerodynamic characteristics of a small, open-jet wind tunnel in an anechoic room. The jet nozzle was 102 mm diameter and was operated subsonically. The anechoic-room dimensions were 7.6 m by 5.5 m by 3.4 m high (wedge tip to wedge tip). Noise contours in the chamber were determined by various jet speeds and exhaust collector positions. The optimum nozzle/collector separation from an acoustic standpoint was 2.1 m. Jet velocity profiles and turbulence levels were measured using pressure probes and hot wires. The jet was found to be symmetric, with no unusual characteristics. The turbulence measurements were hampered by oil mist contamination of the airflow.

  3. LLNL heart valve condition classification project anechoic testing results at the TRANSDEC evaluation facility

    SciTech Connect

    Candy, J V

    1999-10-31

    This report first briefly outlines the procedures and support/activation fixture developed at LLNL to perform the heart valve tests in an anechoic-like tank at the US Navy Transducer Evaluation Facility (TransDec) located in San Diego, CA. Next they discuss the basic experiments performed and the corresponding experimental plan employed to gather meaningful data systematically. The signal processing required to extract the desired information is briefly developed along with some of the data. Finally, they show the results of the individual runs for each valve, point out any of the meaningful features and summaries.

  4. Investigation on High Performance of 10m Semi Anechoic Chamber by using Open-Top Hollow Pyramidal Hybrid EM Wave Absorber

    NASA Astrophysics Data System (ADS)

    Kurihara, Hiroshi; Saito, Toshifumi; Suzuki, Yoshikazu; Nishikata, Atsuhiro; Hashimoto, Osamu

    The emission radiated from electric and electronic equipments is evaluated through OATS. Recently, it is not fully prepared the environment for OATS because of a variety of communication radiation sources (e.g., digital television broadcast and cellular phone station). Therefore, the EM anechoic chambers are becoming more and more important as EMI test site. On the other hand, the EM anechoic chambers are needed high performance in order to cut down EMI countermeasure cost and calculate the antenna factor. The objective of this paper is mainly to present the EM wave absorber design in order to obtain within ±2dB against the theoretical site attenuation values in the 10m semi anechoic chamber at 30MHz to 300MHz. We get the necessary reflectivity of EM wave absorber by the basic site attenuation equation. We design the open-top hollow pyramidal new hybrid EM wave absorber consisted of 180cm long dielectric loss foam and ferrite tiles. Then, we design the 10m semi anechoic chamber by using the ray-tracing simulation and construct it in the size of L24m×W15.2m×H11.2m. More over, we measure the site attenuation of the constructed 10m semi anechoic chamber by using the broadband calculable dipole antennas. As the result, we confirm the validity of the designed open-top hollow pyramidal new hybrid EM wave absorber.

  5. Effectiveness of an inlet flow turbulence control device to simulate flight noise fan in an anechoic chamber

    NASA Technical Reports Server (NTRS)

    Woodward, R. P.; Wazyniak, J. A.; Shaw, L. M.; Mackinnon, M. J.

    1977-01-01

    A hemispherical inlet flow control device was tested on a 50.8 cm. (20-inch) diameter fan stage in the NASA-Lewis anechoic chamber. The control device used honeycomb and wire mesh to reduce turbulence intensities entering the fan. Far field acoustic power level results show about a 5 db reduction in blade passing tone and about 10 dB reduction in multiple pure tone sound power at 90% design fan speed with the inlet device in place. Hot film cross probes were inserted in the inlet to obtain data for two components of the turbulence at 65 and 90% design fan speed. Without the flow control device, the axial intensities were below 1.0%, while the circumferential intensities were almost twice this value. The inflow control device significantly reduced the circumferential turbulence intensities and also reduced the axial length scale.

  6. National Ignition Facility Target Chamber

    SciTech Connect

    Wavrik, R W; Cox, J R; Fleming, P J

    2000-10-05

    On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method of fabrication and construction of the aluminum target chamber was devised by Pitt-Des Moines, Inc. (PDM). PDM also participated in the design of the chamber in areas such as the Target Chamber Realignment and Adjustment System, which would allow realignment of the sphere laser beams in the event of earth settlement or movement from a seismic event. During the fabrication of the target chamber the sphericity tolerances had to be addressed for the individual plates. Procedures were developed for forming, edge preparation and welding of individual plates. Construction plans were developed to allow the field construction of the target chamber to occur parallel to other NIF construction activities. This was

  7. Space Power Facility Reverberation Chamber Calibration Report

    NASA Technical Reports Server (NTRS)

    Lewis, Catherine C.; Dolesh, Robert J.; Garrett, Michael J.

    2014-01-01

    This document describes the process and results of calibrating the Space Environmental Test EMI Test facility at NASA Plum Brook Space Power Facility according to the specifications of IEC61000-4-21 for susceptibility testing from 100 MHz to 40 GHz. The chamber passed the field uniformity test, in both the empty and loaded conditions, making it the world's largest Reverberation Chamber.

  8. X-43A Undergoing Controlled Radio Frequency Testing in the Benefield Anechoic Facility at Edwards Ai

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The X-43A Hypersonic Experimental (Hyper-X) Vehicle hangs suspended in the cavernous Benefield Aenechoic Facility at Edwards Air Force Base during radio frequency tests in January 2000. Hyper-X, the flight vehicle for which is designated as X-43A, is an experimental flight-research program seeking to demonstrate airframe-integrated, 'air-breathing' engine technologies that promise to increase payload capacity for future vehicles, including hypersonic aircraft (faster than Mach 5) and reusable space launchers. This multiyear program is currently underway at NASA Dryden Flight Research Center, Edwards, California. The Hyper-X schedule calls for its first flight later this year (2000). Hyper-X is a joint program, with Dryden sharing responsibility with NASA's Langley Research Center, Hampton, Virginia. Dryden's primary role is to fly three unpiloted X-43A research vehicles to validate engine technologies and hypersonic design tools as well as the hypersonic test facility at Langley. Langley manages the program and leads the technology development effort. The Hyper-X Program seeks to significantly expand the speed boundaries of air-breathing propulsion by being the first aircraft to demonstrate an airframe-integrated, scramjet-powered free flight. Scramjets (supersonic-combustion ramjets) are ramjet engines in which the airflow through the whole engine remains supersonic. Scramjet technology is challenging because only limited testing can be performed in ground facilities. Long duration, full-scale testing requires flight research. Scramjet engines are air-breathing, capturing their oxygen from the atmosphere. Current spacecraft, such as the Space Shuttle, are rocket powered, so they must carry both fuel and oxygen for propulsion. Scramjet technology-based vehicles need to carry only fuel. By eliminating the need to carry oxygen, future hypersonic vehicles will be able to carry heavier payloads. Another unique aspect of the X-43A vehicle is the airframe integration

  9. Design and Characterization of the UTIAS Anechoic Wind Tunnel

    NASA Astrophysics Data System (ADS)

    Chow, Derrick H. F.

    The anechoic open-jet wind tunnel facility at the University of Toronto Institute for Aerospace Studies was updated and characterized to meet the needs of current and future aeroacoustic experiments. The wind tunnel inlet was resurfaced and flow-conditioning screens were redesigned to improve the freestream turbulence intensity to below 0.4% in the test section. The circular nozzle was replaced with a square secondary contraction that increased the maximum test section velocity to 75 m/s and improved flow uniformity to over 99% across a usable cross-sectional area of 500 mm x 500 mm. Acoustic baffles were installed in front of the wind tunnel inlet and foam wedges were installed in the anechoic chamber. The overall background sound pressure levels in the chamber were improved by 8-18 db over the range of operational freestream velocities. The anechoic chamber cut-off frequency is 170 Hz and the reverberation time for a 60 dB sound power decay is 0.032 s.

  10. Indian LSSC (Large Space Simulation Chamber) facility

    NASA Technical Reports Server (NTRS)

    Brar, A. S.; Prasadarao, V. S.; Gambhir, R. D.; Chandramouli, M.

    1988-01-01

    The Indian Space Agency has undertaken a major project to acquire in-house capability for thermal and vacuum testing of large satellites. This Large Space Simulation Chamber (LSSC) facility will be located in Bangalore and is to be operational in 1989. The facility is capable of providing 4 meter diameter solar simulation with provision to expand to 4.5 meter diameter at a later date. With such provisions as controlled variations of shroud temperatures and availability of infrared equipment as alternative sources of thermal radiation, this facility will be amongst the finest anywhere. The major design concept and major aspects of the LSSC facility are presented here.

  11. Making an anechoic choral recording

    NASA Astrophysics Data System (ADS)

    Freiheit, Ron; Alexander, John; Ferguson, John

    2005-09-01

    The utilization of auralization as a tool for acoustic analysis continues to grow and develop. An important element for successful auralization listening experiences is the selection of anechoic source material. In researching the current library of anechoically recorded source material, it was discovered that choral material was not readily available. The Wenger Corporation, St. Olaf College, and 3M undertook a joint project to create an anechoic choral recording. The paper describes the challenges of this recording project-from the technological, logistical, and musical standpoints-and the solutions that were successfully implemented.

  12. Electromagnetic Radiation (EMR) coupling to complex systems : aperture coupling into canonical cavities in reverberant and anechoic environments and model validation.

    SciTech Connect

    Charley, Dawna R.; Higgins, Matthew B.

    2007-12-01

    Mode-stirred chamber and anechoic chamber measurements were made on two sets of canonical test objects (cylindrical and rectangular) with varying numbers of thin slot apertures. The shielding effectiveness was compared to determine the level of correction needed to compensate the mode-stirred data to levels commensurate with anechoic data from the same test object.

  13. A multiple sampling ionization chamber for the External Target Facility

    NASA Astrophysics Data System (ADS)

    Zhang, X. H.; Tang, S. W.; Ma, P.; Lu, C. G.; Yang, H. R.; Wang, S. T.; Yu, Y. H.; Yue, K.; Fang, F.; Yan, D.; Zhou, Y.; Wang, Z. M.; Sun, Y.; Sun, Z. Y.; Duan, L. M.; Sun, B. H.

    2015-09-01

    A multiple sampling ionization chamber used as a particle identification device for high energy heavy ions has been developed for the External Target Facility. The performance of this detector was tested with a 239Pu α source and RI beams. A Z resolution (FWHM) of 0.4-0.6 was achieved for nuclear fragments of 18O at 400 AMeV.

  14. Static and wind tunnel near-field/far-field jet noise measurements from model scale single-flow base line and suppressor nozzles. Summary report. [conducted in the Boeing large anechoic test chamber and the NASA-Ames 40by 80-foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Jaeck, C. L.

    1977-01-01

    A test program was conducted in the Boeing large anechoic test chamber and the NASA-Ames 40- by 80-foot wind tunnel to study the near- and far-field jet noise characteristics of six baseline and suppressor nozzles. Static and wind-on noise source locations were determined. A technique for extrapolating near field jet noise measurements into the far field was established. It was determined if flight effects measured in the near field are the same as those in the far field. The flight effects on the jet noise levels of the baseline and suppressor nozzles were determined. Test models included a 15.24-cm round convergent nozzle, an annular nozzle with and without ejector, a 20-lobe nozzle with and without ejector, and a 57-tube nozzle with lined ejector. The static free-field test in the anechoic chamber covered nozzle pressure ratios from 1.44 to 2.25 and jet velocities from 412 to 594 m/s at a total temperature of 844 K. The wind tunnel flight effects test repeated these nozzle test conditions with ambient velocities of 0 to 92 m/s.

  15. The Kevlar-walled anechoic wind tunnel

    NASA Astrophysics Data System (ADS)

    Devenport, William J.; Burdisso, Ricardo A.; Borgoltz, Aurelien; Ravetta, Patricio A.; Barone, Matthew F.; Brown, Kenneth A.; Morton, Michael A.

    2013-08-01

    The aerodynamic and acoustic performance of an anechoic wind tunnel test section with walls made from thin Kevlar cloth have been measured and analyzed. The Kevlar test section offers some advantages over a conventional free-jet arrangement. The cloth contains the bulk of the flow but permits the transmission of sound with little loss. The containment results in smaller far-field aerodynamic corrections meaning that larger models can be tested at higher Reynolds numbers. The containment also eliminates the need for a jet catcher and allows for a much longer test section. Model-generated noise is thus more easily separated from facility background using beamforming. Measurements and analysis of acoustic and aerodynamic corrections for a Kevlar-walled test section are presented and discussed, along with benchmark trailing edge noise measurements.

  16. Mode-Stirred Method Implementation for HIRF Susceptibility Testing and Results Comparison with Anechoic Method

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Koppen, Sandra V.

    2001-01-01

    This paper describes the implementation of mode-stirred method for susceptibility testing according to the current DO-160D standard. Test results on an Engine Data Processor using the implemented procedure and the comparisons with the standard anechoic test results are presented. The comparison experimentally shows that the susceptibility thresholds found in mode-stirred method are consistently higher than anechoic. This is consistent with the recent statistical analysis finding by NIST that the current calibration procedure overstates field strength by a fixed amount. Once the test results are adjusted for this value, the comparisons with the anechoic results are excellent. The results also show that test method has excellent chamber to chamber repeatability. Several areas for improvements to the current procedure are also identified and implemented.

  17. Method for material characterization in a non-anechoic environment

    NASA Astrophysics Data System (ADS)

    Pometcu, L.; Sharaiha, A.; Benzerga, R.; Tamas, R. D.; Pouliguen, P.

    2016-04-01

    This paper presents a characterization method for extracting the reflection coefficient of materials and the real part of their permittivity. The characterization is performed in a real environment, as opposed to the classical measurement methods that require an anechoic chamber. In order to reduce the effects of the multipath propagation, a free space bistatic measurement was performed at different distances material-antennas in far field. By using a Teflon sample and a commercial absorbing material sample, measurements have been performed in order to validate the characterization technique.

  18. Trade study comparing specimen chamber servicing methods for the Space Station Centrifuge Facility

    NASA Technical Reports Server (NTRS)

    Calvisi, Michael L.; Sun, Sidney C.

    1991-01-01

    The Specimen Chamber Service Unit, a component of the Space Station Centrifuge Facility, must provide a clean enclosure on a continuing basis for the facility's plant, rodent and primate specimens. The specimen chambers can become soiled and can require periodic servicing to maintain a clean environment for the specimens. Two methods of servicing the specimen chambers are discussed: washing the chambers with an on-board washer, or disposing of the soiled chambers and replacing them with clean ones. Many of these issues are addressed by developing several servicing options, using either cleaning or replacement as the method of providing clean specimen chambers, and then evaluating each option according to a set of established quantitative and qualitative criteria. Disposing and replacing the Specimen Chambers is preferable to washing them.

  19. A new plant chamber facility, PLUS, coupled to the atmosphere simulation chamber SAPHIR

    NASA Astrophysics Data System (ADS)

    Hohaus, T.; Kuhn, U.; Andres, S.; Kaminski, M.; Rohrer, F.; Tillmann, R.; Wahner, A.; Wegener, R.; Yu, Z.; Kiendler-Scharr, A.

    2016-03-01

    A new PLant chamber Unit for Simulation (PLUS) for use with the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) has been built and characterized at the Forschungszentrum Jülich GmbH, Germany. The PLUS chamber is an environmentally controlled flow-through plant chamber. Inside PLUS the natural blend of biogenic emissions of trees is mixed with synthetic air and transferred to the SAPHIR chamber, where the atmospheric chemistry and the impact of biogenic volatile organic compounds (BVOCs) can be studied in detail. In PLUS all important environmental parameters (e.g., temperature, photosynthetically active radiation (PAR), soil relative humidity (RH)) are well controlled. The gas exchange volume of 9.32 m3 which encloses the stem and the leaves of the plants is constructed such that gases are exposed to only fluorinated ethylene propylene (FEP) Teflon film and other Teflon surfaces to minimize any potential losses of BVOCs in the chamber. Solar radiation is simulated using 15 light-emitting diode (LED) panels, which have an emission strength up to 800 µmol m-2 s-1. Results of the initial characterization experiments are presented in detail. Background concentrations, mixing inside the gas exchange volume, and transfer rate of volatile organic compounds (VOCs) through PLUS under different humidity conditions are explored. Typical plant characteristics such as light- and temperature- dependent BVOC emissions are studied using six Quercus ilex trees and compared to previous studies. Results of an initial ozonolysis experiment of BVOC emissions from Quercus ilex at typical atmospheric concentrations inside SAPHIR are presented to demonstrate a typical experimental setup and the utility of the newly added plant chamber.

  20. A new plant chamber facility PLUS coupled to the atmospheric simulation chamber SAPHIR

    NASA Astrophysics Data System (ADS)

    Hohaus, T.; Kuhn, U.; Andres, S.; Kaminski, M.; Rohrer, F.; Tillmann, R.; Wahner, A.; Wegener, R.; Yu, Z.; Kiendler-Scharr, A.

    2015-11-01

    A new PLant chamber Unit for Simulation (PLUS) for use with the atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) has been build and characterized at the Forschungszentrum Jülich GmbH, Germany. The PLUS chamber is an environmentally controlled flow through plant chamber. Inside PLUS the natural blend of biogenic emissions of trees are mixed with synthetic air and are transferred to the SAPHIR chamber where the atmospheric chemistry and the impact of biogenic volatile organic compounds (BVOC) can be studied in detail. In PLUS all important enviromental parameters (e.g. temperature, PAR, soil RH etc.) are well-controlled. The gas exchange volume of 9.32 m3 which encloses the stem and the leafes of the plants is constructed such that gases are exposed to FEP Teflon film and other Teflon surfaces only to minimize any potential losses of BVOCs in the chamber. Solar radiation is simulated using 15 LED panels which have an emission strength up to 800 μmol m-2 s-1. Results of the initial characterization experiments are presented in detail. Background concentrations, mixing inside the gas exchange volume, and transfer rate of volatile organic compounds (VOC) through PLUS under different humidity conditions are explored. Typical plant characteristics such as light and temperature dependent BVOC emissions are studied using six Quercus Ilex trees and compared to previous studies. Results of an initial ozonolysis experiment of BVOC emissions from Quercus Ilex at typical atmospheric concentrations inside SAPHIR are presented to demonstrate a typical experimental set up and the utility of the newly added plant chamber.

  1. Evaluation of Gas-filled Ionization Chamber Method for Radon Measurement at Two Reference Facilities

    SciTech Connect

    Ishikawa, Tetsuo; Tokonami, Shinji; Kobayashi, Yosuke; Sorimachi, Atsuyuki; Yatabe, Yoshinori; Miyahara, Nobuyuki

    2008-08-07

    For quality assurance, gas-filled ionization chamber method was tested at two reference facilities for radon calibration: EML (USA) and PTB (Germany). Consequently, the radon concentrations estimated by the ionization chamber method were in good agreement with the reference radon concentrations provided by EML as well as PTB.

  2. The crop growth research chamber: A ground-based facility for CELSS research

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.

    1990-01-01

    A ground based facility for the study of plant growth and development under stringently controlled environments is being developed by the Closed Ecological Life Support System (CELSS) program at the Ames Research Center. Several Crop Growth Research Chambers (CGRC) and laboratory support equipment provide the core of this facility. The CGRC is a closed (sealed) system with a separate recirculating atmosphere and nutrient delivery systems. The atmospheric environment, hydroponic environment, systems controls, and data acquisition are discussed.

  3. Analysis of electromagnetic pulse (EMP) measurements in the National Ignition Facility's target bay and chamber

    NASA Astrophysics Data System (ADS)

    Brown, C. G.; Clancy, T. J.; Eder, D. C.; Ferguson, W.; Throop, A. L.

    2013-11-01

    From May 2009 to the present we have recorded electromagnetic pulse (EMP) strength and spectrum (100 MHz - 5 GHz) in the target bay and chamber of the National Ignition Facility (NIF). The dependence of EMP strength and frequency spectrum on target type and laser energy is discussed. The largest EMP measured was for relatively low-energy, short-pulse (100 ps) flat targets.

  4. A facility for long-term Mars simulation experiments: the Mars Environmental Simulation Chamber (MESCH).

    PubMed

    Jensen, Lars Liengaard; Merrison, Jonathan; Hansen, Aviaja Anna; Mikkelsen, Karina Aarup; Kristoffersen, Tommy; Nørnberg, Per; Lomstein, Bente Aagaard; Finster, Kai

    2008-06-01

    We describe the design, construction, and pilot operation of a Mars simulation facility comprised of a cryogenic environmental chamber, an atmospheric gas analyzer, and a xenon/mercury discharge source for UV generation. The Mars Environmental Simulation Chamber (MESCH) consists of a double-walled cylindrical chamber. The double wall provides a cooling mantle through which liquid N(2) can be circulated. A load-lock system that consists of a small pressure-exchange chamber, which can be evacuated, allows for the exchange of samples without changing the chamber environment. Fitted within the MESCH is a carousel, which holds up to 10 steel sample tubes. Rotation of the carousel is controlled by an external motor. Each sample in the carousel can be placed at any desired position. Environmental data, such as temperature, pressure, and UV exposure time, are computer logged and used in automated feedback mechanisms, enabling a wide variety of experiments that include time series. Tests of the simulation facility have successfully demonstrated its ability to produce temperature cycles and maintain low temperature (down to -140 degrees C), low atmospheric pressure (5-10 mbar), and a gas composition like that of Mars during long-term experiments. PMID:18593229

  5. Anechoic aquarium for ultrasonic neural telemetry.

    PubMed Central

    Mensinger, A F; Deffenbaugh, M

    2000-01-01

    An acoustic neural telemetry tag has been developed for recording from free-swimming aquatic animals. Microwire electrodes were implanted into the VIIIth nerve of the toadfish, Opsanus tau, and interfaced to the subdermally implanted tag. The telemetry tag frequency modulates the neural signal, converting it into a varying frequency, which is amplified and transmitted acoustically (centre frequency of 90 kHz and a 20 kHz bandwidth). This acoustic signal is detected by a receiver hydrophone, and the receiver reconstructs the full neural waveform from the acoustic signal. However, due to the multipath environment in the experimental aquarium, the acoustic signal is quickly degraded as the hydrophone is moved away from the source. In order to receive the signal independent of fish position, an anechoic aquarium was designed. Streams of microbubbles (ca. 70 microm diameter) were generated to produce a curtain of sound-absorptive material along the walls and water surface of the aquarium. Microbubble generation significantly reduced the multipath artefacts, and allowed signal discrimination independent of fish and hydrophone position. The anechoic aquarium will allow the recording of neural activity from free-swimming fishes in quasi-natural habitats, thus allowing better understanding of the neural mechanisms of behaviour. PMID:11079420

  6. A large hemi-anechoic enclosure for community-compatible aeroacoustic testing of aircraft propulsion systems

    NASA Astrophysics Data System (ADS)

    Cooper, Beth A.

    A large hemi-anechoic (absorptive walls and acoustically hard floor) noise control enclosure has been erected around a complex of test stands at the NASA Lewis Research Center in Cleveland, Ohio. This new state-of-the-art Aeroacoustic Propulsion Laboratory (APL) provides an all-weather, semisecure test environment while limiting noise to acceptable levels in surrounding residential neighborhoods. The 39.6 m (130 ft) diameter geodesic dome structure houses the new Nozzle Aeroacoustic Test Rig (NATR), an ejector-powered M = 0.3 free jet facility for acoustic testing of supersonic aircraft exhaust nozzles and turbomachinery. A multi-axis, force-measuring Powered Lift Facility (PLF) stand for testing of Short Takeoff Vertical Landing (STOVL) vehicles is also located within the dome. The design of the Aeroacoustic Propulsion Laboratory efficiently accomodates the research functions of two separate test rigs, one of which (NATR) requires a specialized environment for taking acoustic measurements. Absorptive fiberglass wedge treatment on the interior surface of the dome provides a hemi-anechoic interior environment for obtaining the accurate acoustic measurements required to meet research program goals. The APL is the first known geodesic dome structure to incorporate transmission-loss properties as well as interior absorption into a free-standing, community-compatible, hemi-anechoic test facility.

  7. A Large Hemi-Anechoic Enclosure for Community-Compatible Aeroacoustic Testing of Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Cooper, Beth A.

    1993-01-01

    A large hemi-anechoic (absorptive walls and acoustically hard floor) noise control enclosure has been erected around a complex of test stands at the NASA Lewis Research Center in Cleveland, Ohio. This new state-of-the-art Aeroacoustic Propulsion Laboratory (APL) provides an all-weather, semisecure test environment while limiting noise to acceptable levels in surrounding residential neighborhoods. The 39.6 m (130 ft) diameter geodesic dome structure houses the new Nozzle Aeroacoustic Test Rig (NATR), an ejector-powered M = 0.3 free jet facility for acoustic testing of supersonic aircraft exhaust nozzles and turbomachinery. A multi-axis, force-measuring Powered Lift Facility (PLF) stand for testing of Short Takeoff Vertical Landing (STOVL) vehicles is also located within the dome. The design of the Aeroacoustic Propulsion Laboratory efficiently accomodates the research functions of two separate test rigs, one of which (NATR) requires a specialized environment for taking acoustic measurements. Absorptive fiberglass wedge treatment on the interior surface of the dome provides a hemi-anechoic interior environment for obtaining the accurate acoustic measurements required to meet research program goals. The APL is the first known geodesic dome structure to incorporate transmission-loss properties as well as interior absorption into a free-standing, community-compatible, hemi-anechoic test facility.

  8. Characterization of the Reverberation Chamber at the NASA Langley Structural Acoustics Loads and Transmission (SALT) Facility

    NASA Technical Reports Server (NTRS)

    Grosveld, Ferdinand W.

    2013-01-01

    In 2011 the noise generating capabilities in the reverberation chamber of the Structural Acoustic Loads and Transmission (SALT) facility at NASA Langley Research Center were enhanced with two fiberglass reinforced polyester resin exponential horns, each coupled to Wyle Acoustic Source WAS-3000 airstream modulators. This report describes the characterization of the reverberation chamber in terms of the background noise, diffusivity, sound pressure levels, the reverberation times and the related overall acoustic absorption in the empty chamber and with the acoustic horn(s) installed. The frequency range of interest includes the 80 Hz to 8000 Hz one-third octave bands. Reverberation time and sound pressure level measurements were conducted and standard deviations from the mean were computed. It was concluded that a diffuse field could be produced above the Schroeder frequency in the 400 Hz one-third octave band and higher for all applications. This frequency could be lowered by installing panel diffusers or moving vanes to improve the acoustic modal overlap in the chamber. In the 80 Hz to 400 Hz one-third octave bands a successful measurement will be dependent on the type of measurement, the test configuration, the source and microphone locations and the desired accuracy. It is recommended that qualification measurements endorsed in the International Standards be conducted for each particular application.

  9. Ion-chamber-based loss monitor system for the Los Alamos Meson Physics Facility

    SciTech Connect

    Plum, M.A.; Brown, D.; Browman, A.; Macek, R.J.

    1995-05-01

    A new loss monitor system has been designed and installed at the Los Alamos Meson Physics Facility (LAMPF). The detectors are ion chambers filled with N{sub 2} gas. The electronics modules have a threshold range of 1:100, and they can resolve changes in beam loss of about 2% of the threshold settings. They can generate a trip signal in 2 {mu}s if the beam loss is large enough; if the response time of the Fast Protect System is included the beam will be shut off in about 37 {mu}s.

  10. Formation of Brown Aqueous Secondary Organic Aerosol during Multiphase Cloud Simulations using the CESAM Chamber Facility

    NASA Astrophysics Data System (ADS)

    Hawkins, L. N.; Welsh, H.; De Haan, D. O.; Doussin, J. F.; Pednekar, R.; Caponi, L.; Pangui, E.; Gratien, A.; Cazaunau, M.; Formenti, P.; Pajunoja, A.

    2015-12-01

    We investigated the formation of aqueous brown carbon (aqBrC) from methylglyoxal and methylamine in multiphase reactions using the CESAM chamber facility at the University Paris-Est Creteil. Following reaction in the chamber, droplets and particles were sampled with a Particle-Into-Liquid-Sampler (PILS), a capillary waveguide cell for UV/visible spectroscopy, and a total organic carbon analyzer (TOC). Particle size distributions were measured with a scanning mobility particle sizer and used to determine the mass absorption coefficient (a normalized absorbance measurement). Absorption spectra were recorded while aerosol or gas phase aqBrC precursors were introduced into the humid chamber. Sampling was continuous during and after cloud events. The events lasted 5-10 minutes and produced measurable brown carbon signal at 365 nm. When lights were used, absorbance at 365 nm decreased steadily indicating photobleaching of aqBrC products or preferential formation of different, non-absorbing products. Although absorptivity increases prior to cloud formation, cloud events produce sharp increased in aqBrC absorptivity. While measurable absorbance at 365 nm indicates aqBrC formation, very little absorbance was recorded beyond 450 nm indicating that the products were not as oligomerized as products observed in prior work in multi-day, bulk phase simulations.

  11. University of Missouri-Rolla cloud simulation facility - Proto II chamber

    NASA Technical Reports Server (NTRS)

    White, Daniel R.; Carstens, John C.; Hagen, Donald E.; Schmitt, John L.; Kassner, James L.

    1987-01-01

    The design and supporting systems for the cooled-wall expansion cloud chamber, designated Proto II, are described. The chamber is a 10-sided vertical cylinder designed to be operated with interior wall temperatures between +40 and -40 C, and is to be utilized to study microphysical processes active in atmospheric clouds and fogs. Temperatures are measured using transistor thermometers which have a range of + or - 50 C and a resolution of about + or - 0.001 C; and pressures are measured in the chamber by a differential strain gauge pressure transducer. The methods used for temperature and pressure control are discussed. Consideration is given to the chamber windows, optical table, photographic/video, optical attenuation, Mie scattering, and the scanning system for the chamber. The system's minicomputer and humidifier, sample preparation, and chamber flushing are examined.

  12. Performance of a liquid argon time projection chamber exposed to the CERN West Area Neutrino Facility neutrino beam

    SciTech Connect

    Arneodo, F.; Cavanna, F.; Mitri, I. De; Mortari, G. Piano; Benetti, P.; Borio di Tigliole, A.; Calligarich, E.; Cesana, E.; Dolfini, R.; Mauri, F.; Montanari, C.; Rappoldi, A.; Raselli, G. L.; Rubbia, C.; Terrani, M.; Vignoli, C.; Bonesini, M.; Boschetti, B.; Cavalli, D.; Curioni, A.

    2006-12-01

    We present the results of the first exposure of a Liquid Argon TPC to a multi-GeV neutrino beam. The data have been collected with a 50 liters ICARUS-like chamber located between the CHORUS and NOMAD experiments at the CERN West Area Neutrino Facility (WANF). We discuss both the instrumental performance of the detector and its capability to identify and reconstruct low-multiplicity neutrino interactions.

  13. The ASIBIA sea-ice facility: First results from the Atmosphere-Sea-Ice-Biogeochemistry in the Arctic chamber

    NASA Astrophysics Data System (ADS)

    France, James L.; Thomas, Max

    2016-04-01

    Working in the natural ocean-ice-atmosphere system is very difficult, as conducting fieldwork on sea-ice presents many challenges ice including costs, safety, experimental controls and access. The new ASIBIA (Atmosphere-Sea-Ice-Biogeochemistry in the Arctic) coupled Ocean-Sea-Ice-(Snow)-Atmosphere chamber facility at the University of East Anglia, UK, we are aiming to perform controlled first-year sea-ice investigations in areas such as sea-ice physics, physicochemical and biogeochemical processes in sea-ice and quantification of the bi-directional flux of gases in various states of first-year sea-ice conditions. The facility is a medium sized chamber with programmable temperatures from -55°C to +30°C, allowing a full range of first year sea-ice growing conditions in both the Arctic and Antarctic to be simulated. The water depth can be up to 1 m (including up to 25 cm of sea-ice) and an optional 1 m tall Teflon film atmosphere on top of the sea-ice, thus creating a closed and coupled ocean-sea-ice-atmosphere mesocosm. Ice growth in the tank is well suited for studying first-year sea-ice physical properties, with in-situ ice-profile measurements of temperature, salinity, conductivity, pressure and spectral light transmission. Underwater and above ice cameras are installed to record the physical development of the sea-ice. Here, we present the data from the first suites of experiments in the ASIBIA chamber focussing on sea-ice physics and give a brief description of the capabilities of the facility going forward. The ASIBIA chamber was funded as part of an ERC consolidator grant to the late Prof. Roland von Glasow and we hope this work and further development of the facility will act as a lasting legacy.

  14. Anechoic wind tunnel study of turbulence effects on wind turbine broadband noise

    NASA Technical Reports Server (NTRS)

    Loyd, B.; Harris, W. L.

    1995-01-01

    This paper describes recent results obtained at MIT on the experimental and theoretical modelling of aerodynamic broadband noise generated by a downwind rotor horizontal axis wind turbine. The aerodynamic broadband noise generated by the wind turbine rotor is attributed to the interaction of ingested turbulence with the rotor blades. The turbulence was generated in the MIT anechoic wind tunnel facility with the aid of biplanar grids of various sizes. The spectra and the intensity of the aerodynamic broadband noise have been studied as a function of parameters which characterize the turbulence and of wind turbine performance parameters. Specifically, the longitudinal integral scale of turbulence, the size scale of turbulence, the number of turbine blades, and free stream velocity were varied. Simultaneous measurements of acoustic and turbulence signals were made. The sound pressure level was found to vary directly with the integral scale of the ingested turbulence but not with its intensity level. A theoretical model based on unsteady aerodynamics is proposed.

  15. A Concept for a Low Pressure Noble Gas Fill Intervention in the IFE Fusion Test Facility (FTF) Target Chamber

    SciTech Connect

    Gentile, C. A.; Blanchard, W. R.; Kozub, T. A.; Aristova, M.; McGahan, C.; Natta, S.; Pagdon, K.; Zelenty, J.

    2010-01-14

    An engineering evaluation has been initiated to investigate conceptual engineering methods for implementing a viable gas shield strategy in the Fusion Test Facility (FTF) target chamber. The employment of a low pressure noble gas in the target chamber to thermalize energetic helium ions prior to interaction with the wall could dramatically increase the useful life of the first wall in the FTF reactor1. For the purpose of providing flexibility, two target chamber configurations are addressed: a five meter radius sphere and a ten meter radius sphere. Experimental studies at Nike have indicated that a low pressure, ambient gas resident in the target chamber during laser pulsing does not appear to impair the ability of laser light from illuminating targets2. In addition, current investigations into delivering, maintaining, and processing low pressure gas appear to be viable with slight modification to current pumping and plasma exhaust processing technologies3,4. Employment of a gas fill solution for protecting the dry wall target chamber in the FTF may reduce, or possibly eliminate the need for other attenuating technologies designed for keeping He ions from implanting in first wall structures and components. The gas fill concept appears to provide an effective means of extending the life of the first wall while employing mostly commercial off the shelf (COTS) technologies. Although a gas fill configuration may provide a methodology for attenuating damage inflicted on chamber surfaces, issues associated with target injection need to be further analyzed to ensure that the gas fill concept is viable in the integrated FTF design5. In the proposed system, the ambient noble gas is heated via the energetic helium ions produced by target detonation. The gas is subsequently cooled by the chamber wall to approximately 800oC, removed from the chamber, and processed by the chamber gas processing system (CGPS). In an optimized scenario of the above stated concept, the chamber

  16. Processing of Prosthetic Heart Valve Sounds from Anechoic Tank Measurements

    SciTech Connect

    Candy, J V; Meyer, A W

    2001-03-20

    People with serious cardiac problems have had their life span extended with the development of the prosthetic heart valve. However, the valves operate continuously at approximately 39 million cycles per year and are therefore subject to structural failures either by faulty design or material fatigue. The development of a non-invasive technique using an acoustic contact microphone and sophisticated signal processing techniques has been proposed and demonstrated on limited data sets. In this paper we discuss an extension of the techniques to perform the heart valve tests in an anechoic like. Here the objective is to extract a ''pure'' sound or equivalently the acoustical vibration response of the prosthetic valves in a quiet environment. The goal is to demonstrate that there clearly exist differences between values which have a specific mechanical defect known as single leg separation (SLS) and non-defective valves known as intact (INT). We discuss the signal processing and results of anechoic acoustic measurements on 50 prosthetic valves in the tank. Finally, we show the results of the individual runs for each valve, point out any of the meaningful features that could be used to distinguish the SLS from INT and summarize the experiments.

  17. Management of unconverted light for the National Ignition Facility target chamber

    SciTech Connect

    Anderson, A. T.; Bletzer, K.; Burnham, A. K.; Dixit, S; Genin, F. Y.; Hibbard, W.; Norton, J.; Scott, J. M.; Whitman, P. K.

    1998-07-08

    The NIF target chamber beam dumps must survive high x-ray, laser, ion, and shrapnel exposures without excessive generation of vapors or particulate that will contaminate the final optics debris shields, thereby making the debris shields susceptible to subsequent laser damage. The beam dumps also must be compatible with attaining and maintaining the required target chamber vacuum and must not activate significantly under high neutron fluxes. Finally, they must be developed, fabricated, and maintained for a reasonable cost. The primary challenge for the beam dump is to survive up to 20 J/cm{sup 2} of lpm light and 1 - 2 J/cm{sup 2} of nominally 200 - 350 eV blackbody temperature x rays. Additional threats include target shrapnel, and other contamination issues. Designs which have been evaluated include louvered hot-pressed boron carbide (B{sub 4}C) or stainless steel (SS) panels, in some cases covered with transparent Teflon film, and various combinations of inexpensive low thermal expansion glasses backed by inexpensive absorbing glass. Louvered designs can recondense a significant amount of ablated material that would otherwise escape into the target chamber. Transparent Teflon was evaluated as an alternative way to capture ablated material. The thin Teflon sheet would need to be replaced after each shot since it exhibits both laser damage and considerable x- ray ablation with each shot. Uncontaminated B{sub 4}C, SS, and low thermal expansion glasses have reasonably small x-ray and laser ablation rates, although the glasses begin to fail catastrophically after 100 high fluence shots. Commercially available absorbing glasses require a pre-shield of either Teflon or low thermal expansion glass to prevent serious degradation by the x-ray fluence. Advantages of the hot-pressed B{sub 4}C and SS over glass are their performance against microshrapnel, their relative indifference to contamination, and their ability to be refurbished by aggressive cleaning using CO{sub 2

  18. Classification of heart valve sounds from experiments in an anechoic water tank

    SciTech Connect

    Axelrod, M C; Clark, G A; Scott, D

    1999-06-01

    In vivo studies in both sheep and humans were plagued by a number of problems including movement artifacts, biological noise, low signal-to-noise ratio (SNR), chest-wall reverberation, and limited bandwidth recordings as discussed by [1]. To overcome these problems it was decided to record heart valve sounds under controlled conditions deep in an anechoic water tank, free from reverberation noise, including surface reflections. Experiments were conducted in a deep water tank at the Transdec facility in San Diego, which satisfies these requirements. The Transdec measurements are free of reverberations, but not totally free of acoustic and electrical noise. We used a high quality hydrophone together with a wide-band data acquisition system [2]. We recorded sounds from 100 repetitions of the opening-closing cycles on each of 50 different heart valves, including 21 SLS valves and 29 intact valves. The power spectrum of the opening and closing phases of each cycle were calculated and outlier spectra removed as described by Candy [2]. In this report, we discuss the results of our classification of the heart valve sound measurements. The goal of this classification task was to apply the fundamental classification algorithms developed for the clinical data in 1994 and 1996 to the measurements from the anechoic water tank. From the beginning of this project, LLNL's responsibility has been to process and classify the heart valve opening sounds. For this experiment, however, we processed both the opening sounds and closing sounds for comparison purposes. The results of this experiment show that the classifier did not perform well. We believe this is because of low signal-to-noise ratio and excessive variability in signal power from beat-to-beat for a given valve.

  19. Classification of heart valve sounds from experiments in an anechoic water tank

    SciTech Connect

    Axelrod, M C; Clark, G A; Scott, D

    1999-06-01

    In vivo studies in both sheep and humans were plagued by a number of problems including movement artifacts, biological noise, low signal-to-noise ratio (SNR), chest-wall reverberation, and limited bandwidth recordings as discussed by [1]. To overcome these problems it was decided to record heart valve sounds under controlled conditions deep in an anechoic water tank, free from reverberation noise. The main goal of this experiment was to obtain measurements of ''pure'' heart valve sounds free of the scattering effects of the body. Experiments were conducted at the Transdec facility in San Diego [2]. We used a high quality hydrophone together with a wide-band data acquisition system [2]. We recorded sounds from 100 repetitions of the opening-closing cycles on each of 50 different heart valves, including 21 SLS valves and 29 intact valves. The power spectrum of the opening and closing phases of each cycle were calculated and outlier spectra removed as described by Candy [2]. In this report, we discuss the results of our classification of the heart valve sound measurements. The goal of this classification task was to apply the fundamental classification algorithms developed for the clinical data in 1994 and 1996 to the measurements from the anechoic water tank. From the beginning of this project, LLNL's responsibility has been to process and classify the heart valve sounds. For this experiment, however, we processed both the opening sounds and closing sounds for comparison purposes. The results of this experiment show that the classifier did not perform well because of low signal-to-noise ratio and excessive variability in signal power from beat-to-beat for a given valve.

  20. Venus Pressure Chamber: A Small Testing Facility Available to the Community

    NASA Technical Reports Server (NTRS)

    Johnson, Natasha M.; Wegel, D. C.

    2011-01-01

    Venus is an inhospitable planet where the surface mean. temperature is approximately 740K and the global mean pressure is approximately 95 bars. The atmosphere is comprised mostly of CO2 (approximately 96.5%) and N2 (approximately3.5%) with trace amounts of CO and other reactive gases. Although Venus is very similar in size and mass with the Earth and is Earth's nearest planetary neighbor, it has not received many visitors from Earth, especially those that can land on the surface. The challenge most often cited for this scarcity of surface probes is the workability/survivability of instruments and equipment in Venus' harsh environment. In order to overcome this obstacle, a small pressure chamber has been acquired for use by the scientific community. It is housed at Goddard Space. Flight Center in Maryland and is available to the community for testing of small flight components, instruments and short-term experiments that require high temperatures and pressures.

  1. The Irradiation Characteristics of the Kur Heavy Water Facility (ii) - Neutron and Gamma-Ray Dose Measurements with a Twin-Chamber

    NASA Astrophysics Data System (ADS)

    Sakurai, Yoshinori; Kobayashi, Tooru

    2003-06-01

    The Heavy Water Neutron Irradiation Facility of the Kyoto University Reactor can supply neutron energy spectra from almost pure thermal to mainly epi-thermal, using a spectrum shifter and thermal neutron filters. We will report about the measurement of the neutron and gamma-ray doses using a twin-chamber. The used twin-chamber is the combination of a tissue-equivalent ionization-chamber and a graphite ionization chamber, with detecting volumes of 80 cc. From the comparisons between the chamber-measured dose rates and the nominal values, it was confirmed that the relative dependencies of the neutron and gamma-ray doses on the heavy water thickness, were almost the same, excepting the smaller heavy-water-thickness mode, such as CB-0000-F.

  2. Calibration of a new experimental chamber for PIXE analysis at the Accelerator Facilities Division of Atomic Energy Centre Dhaka (AECD)

    NASA Astrophysics Data System (ADS)

    Hassan, Md. Taufique; Shariff, Md. Asad; Hossein, Amzad; Abedin, Md. Joynal; Fazlul Hoque, A. K. M.; Chowdhuri, M. S.

    2015-05-01

    A new experimental chamber has been installed at the 3 MV Van de Graaff Accelerator Facilities Division in the Atomic Energy Centre, Dhaka, to perform different Ion Beam Analysis (IBA) techniques. The calibration of this new setup for Particle Induced X-ray Emission (PIXE) technique has been done using a set of thin MicroMatter standards and GUPIX (PIXE spectrum analysis software), which is explicated in this paper. The effective thicknesses of the beryllium window of the X-ray detector and of the different absorbers used were determined. For standardization, the so called instrumental constant H (product of detector solid angle and the correction factor for the setup) as function of X-ray energy were determined and stored inside the GUPIX library for further PIXE analysis.

  3. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    SciTech Connect

    Scarpitta, S.C.; Tu, K.W.; Fisenne, I.M.; Cavallo, A.; Perry, P.

    1996-10-01

    Results are presented from the Fifth Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurements conducted in the EML radon exposure and test facility in May 1996. In total, thirty-four government, private and academic facilities participated in the exercise with over 170 passive and electronic devices exposed in the EML test chamber. During the first week of the exercise, passive and continuous measuring devices were exposed (usually in quadruplicate) to about 1,280 Bq m{sup {minus}3} {sup 222}Rn for 1--7 days. Radon progeny measurements were made during the second week of the exercise. The results indicate that all of the tested devices that measure radon gas performed well and fulfill their intended purpose. The grand mean (GM) ratio of the participants` reported values to the EML values, for all four radon device categories, was 0.99 {plus_minus} 0.08. Eighty-five percent of all the radon measuring devices that were exposed in the EML radon test chamber were within {plus_minus}1 standard deviation (SD) of the EML reference values. For the most part, radon progeny measurements were also quite good as compared to the EML values. The GM ratio for the 10 continuous PAEC instruments was 0.90 {plus_minus} 0.12 with 75% of the devices within 1 SD of the EML reference values. Most of the continuous and integrating electronic instruments used for measuring the PAEC underestimated the EML values by about 10--15% probably because the concentration of particles onto which the radon progeny were attached was low (1,200--3,800 particles cm{sup {minus}3}). The equilibrium factor at that particle concentration level was 0.10--0.22.

  4. Sound absorption of a rib-stiffened plate covered by anechoic coatings.

    PubMed

    Fu, Xinyi; Jin, Zhongkun; Yin, Yao; Liu, Bilong

    2015-03-01

    Underwater vehicles are often equipped with anechoic coatings to absorb the sound waves of active sonar and attenuate the noise emitted from the vessels. Rubber layers with periodically distributed air cavities are widely used as anechoic coatings. In this paper, the sound absorption of anechoic coatings embedded with doubly periodic cavities and backed with periodically rib-stiffened plates is investigated using a finite element method (FEM) with Bloch-periodic boundary conditions. Numerical results given by the FEM are compared with those of a simplified transfer impedance approach to explain the shifting of the main absorption peak. Further a simplified FEM approach, which reduces calculation time significantly and maintains the reasonable accuracy, is proposed for a comparison. The results indicate that the plate and the ribs can have significant impacts on the absorption performance of anechoic coatings, especially at low frequencies. PMID:25786965

  5. Sound absorption of a rib-stiffened plate covered by anechoic coatings.

    PubMed

    Fu, Xinyi; Jin, Zhongkun; Yin, Yao; Liu, Bilong

    2015-03-01

    Underwater vehicles are often equipped with anechoic coatings to absorb the sound waves of active sonar and attenuate the noise emitted from the vessels. Rubber layers with periodically distributed air cavities are widely used as anechoic coatings. In this paper, the sound absorption of anechoic coatings embedded with doubly periodic cavities and backed with periodically rib-stiffened plates is investigated using a finite element method (FEM) with Bloch-periodic boundary conditions. Numerical results given by the FEM are compared with those of a simplified transfer impedance approach to explain the shifting of the main absorption peak. Further a simplified FEM approach, which reduces calculation time significantly and maintains the reasonable accuracy, is proposed for a comparison. The results indicate that the plate and the ribs can have significant impacts on the absorption performance of anechoic coatings, especially at low frequencies.

  6. Ultra-light duct for an anechoic wind tunnel

    NASA Technical Reports Server (NTRS)

    Lambourion, J.; Lewy, S.; Papirnyk, O.; Rahier, G.; Remandet, J.-N.

    1989-01-01

    A tunnel ultra-light (or TUL) is a duct composed of acoustically transparent cloth designed to transform an open-jet wind tunnel into a closed-jet wind tunnel. This concept is of interest (a priori) for anechoic wind tunnels because it improves the aerodynamic quality without hindering the measurement of sound in the far field. A full scale device designed for the 3 m diameter test section of CEPRA 19 was described. The apparatus installation did not develop any significant problems, and the mechanical support turned out to be excellent. Aerodynamic and acoustic tests are discussed. Certain imperfections in the installation as tested - instabilities above 25 m/s and acceptable cloth transmission up to 4kHz were revealed. The system as tested could eventually be used in certain applications, for example, in ground based transport. However, the concept of TUL must be developed further to arrive at a reliable mechanism for use in a large number of applications.

  7. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    SciTech Connect

    George, A.C.; Knutson, E.O.; Tu, K.W.; Fisenne, I.M.

    1995-12-01

    The results from the May 1995 Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurement conducted in the EML radon exposure and test facility are presented. Represented were 13 participants that measure radon with open faced and diffusion barrier activated carbon collectors, 10 with nuclear alpha track detectors, 9 with short-term and long-term electret/ionization chambers, and 13 with active and passive commercial electronic continuous monitors. For radon progeny, there were four participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy concentration (PAEC). There were 11 participants with continuous and integrating commercial electronic instruments that are used for measuring the PAEC. The results indicate that all the tested instruments that measure radon fulfill their intended purpose. All instruments and methods used for grab sampling for radon progeny did very well. However, most of the continuous and integrating electronic instruments used for measuring the PAEC or working level appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is <5,000 cm{sup -3}.

  8. CFD Simulation on the J-2X Engine Exhaust in the Center-Body Diffuser and Spray Chamber at the B-2 Facility

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen; Wey, Thomas; Buehrle, Robert

    2009-01-01

    A computational fluid dynamic (CFD) code is used to simulate the J-2X engine exhaust in the center-body diffuser and spray chamber at the Spacecraft Propulsion Facility (B-2). The CFD code is named as the space-time conservation element and solution element (CESE) Euler solver and is very robust at shock capturing. The CESE results are compared with independent analysis results obtained by using the National Combustion Code (NCC) and show excellent agreement.

  9. Capabilities, Design, Construction and Commissioning of New Vibration, Acoustic, and Electromagnetic Capabilities Added to the World's Largest Thermal Vacuum Chamber at NASA's Space Power Facility

    NASA Technical Reports Server (NTRS)

    Motil, Susan M.; Ludwiczak, Damian R.; Carek, Gerald A.; Sorge, Richard N.; Free, James M.; Cikanek, Harry A., III

    2011-01-01

    NASA s human space exploration plans developed under the Exploration System Architecture Studies in 2005 included a Crew Exploration Vehicle launched on an Ares I launch vehicle. The mass of the Crew Exploration Vehicle and trajectory of the Ares I coupled with the need to be able to abort across a large percentage of the trajectory generated unprecedented testing requirements. A future lunar lander added to projected test requirements. In 2006, the basic test plan for Orion was developed. It included several types of environment tests typical of spacecraft development programs. These included thermal-vacuum, electromagnetic interference, mechanical vibration, and acoustic tests. Because of the size of the vehicle and unprecedented acoustics, NASA conducted an extensive assessment of options for testing, and as result, chose to augment the Space Power Facility at NASA Plum Brook Station, of the John H. Glenn Research Center to provide the needed test capabilities. The augmentation included designing and building the World s highest mass capable vibration table, the highest power large acoustic chamber, and adaptation of the existing World s largest thermal vacuum chamber as a reverberant electromagnetic interference test chamber. These augmentations were accomplished from 2007 through early 2011. Acceptance testing began in Spring 2011 and will be completed in the Fall of 2011. This paper provides an overview of the capabilities, design, construction and acceptance of this extraordinary facility.

  10. Hyperechoic renal tumors: anechoic rim and intratumoral cysts in US differentiation of renal cell carcinoma from angiomyolipoma.

    PubMed

    Yamashita, Y; Ueno, S; Makita, O; Ogata, I; Hatanaka, Y; Watanabe, O; Takahashi, M

    1993-07-01

    To determine whether angiomyolipomas (AMLs) and renal cell carcinomas (RCCs) can be differentiated at ultrasonography (US), the authors retrospectively evaluated the sonographic appearances of 31 AMLs and 38 RCCs. Sonograms were evaluated by three radiologists without knowledge of histologic findings, with respect to the echogenicity of the tumor, predominant echotexture, and whether an anechoic rim was present. All patients had also undergone computed tomography (CT) to check for tumoral fat. Intratumoral fat was evident at CT in 28 of the 31 AMLs. RCCs had no fat at CT or histologic evaluation. An anechoic rim was evident in 32 of 38 (84%) RCCs, and 10 RCCs had small anechoic areas with back echo enhancement, which corresponded to intratumoral cysts or cystic necrosis at histologic evaluation. The anechoic rim and areas indicative of cysts were not found in AMLs. Demonstration of an anechoic rim and/or intratumoral cysts in a hyperechoic mass at US suggests that the tumor is an RCC.

  11. Acoustic anechoic layers with singly periodic array of scatterers: Computational methods, absorption mechanisms, and optimal design

    NASA Astrophysics Data System (ADS)

    Yang, Hai-Bin; Li, Yue; Zhao, Hong-Gang; Wen, Ji-Hong; Wen, Xi-Sen

    2014-10-01

    The acoustic properties of anechoic layers with a singly periodic array of cylindrical scatterers are investigated. A method combined plane wave expansion and finite element analysis is extended for out-of-plane incidence. The reflection characteristics of the anechoic layers with cavities and locally resonant scatterers are discussed. The backing is a steel plate followed by an air half space. Under this approximate zero transmission backing condition, the reflection reduction is induced by the absorption enhancement. The absorption mechanism is explained by the scattering/absorption cross section of the isolated scatterer. Three types of resonant modes which can induce efficient absorption are revealed. Due to the fact that the frequencies of the resonant modes are related to the size of the scatterers, anechoic layers with scatterers of mixed size can broaden the absorption band. A genetic optimization algorithm is adopted to design the anechoic layer with scatterers of mixed size at a desired frequency band from 2 kHz to 10 kHz for normal incidence, and the influence of the incident angle is also discussed.

  12. Bakeout Chamber Within Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Taylor, Daniel M.; Soules, David M.; Barengoltz, Jack B.

    1995-01-01

    Vacuum-bakeout apparatus for decontaminating and measuring outgassing from pieces of equipment constructed by mounting bakeout chamber within conventional vacuum chamber. Upgrade cost effective: fabrication and installation of bakeout chamber simple, installation performed quickly and without major changes in older vacuum chamber, and provides quantitative data on outgassing from pieces of equipment placed in bakeout chamber.

  13. Subjective evaluation of auralizations created from multi-channel anechoic recordings of a talker in motion

    NASA Astrophysics Data System (ADS)

    Vigeant, Michelle C.; Wang, Lily M.

    2005-04-01

    A high degree of speech intelligibility is very important in educational environments. When designing such spaces, like classrooms, auralizations can be used to subjectively assess the degree of speech intelligibility and clarity. Auralizations are most commonly made by convolving the impulse response (IR) of an omni-directional source with a single channel anechoic speech recording. This paper explores the idea of using multi-channel recordings to create the auralizations, using a female talker in motion. An omni-directional source is split into quadrants and the IR is calculated for each section. These IR's are convolved with the appropriate channel of the anechoic recording and then the four auralizations are mixed to create one final auralization. The auralizations were made using four-channel anechoic recordings of a person walking on a platform while talking. Subjective tests were conducted to determine the ease with which subjects could identify the direction of the movement of the source in rooms with varying amounts of absorption. This method can be used to create more realistic classroom auralizations, as teachers typically move around the room as they teach. [Work supported by the National Science Foundation.

  14. Exposure chamber

    DOEpatents

    Moss, Owen R.; Briant, James K.

    1983-01-01

    An exposure chamber includes an imperforate casing having a fluid inlet at the top and an outlet at the bottom. A single vertical series of imperforate trays is provided. Each tray is spaced on all sides from the chamber walls. Baffles adjacent some of the trays restrict and direct the flow to give partial flow back and forth across the chambers and downward flow past the lowermost pan adjacent a central plane of the chamber.

  15. Exposure chamber

    DOEpatents

    Moss, Owen R.

    1980-01-01

    A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

  16. Performance of the high speed anechoic wind tunnel at Lyon University

    NASA Technical Reports Server (NTRS)

    Sunyach, M.; Brunel, B.; Comte-Bellot, G.

    1986-01-01

    The characteristics of the feed duct, the wind tunnel, and the experiments run in the convergent-divergent anechoic wind tunnel at Lyon University are described. The wind tunnel was designed to eliminate noise from the entrance of air or from flow interactions with the tunnel walls so that noise caused by the flow-test structure interactions can be studied. The channel contains 1 x 1 x 0.2 m glass and metal foil baffles spaced 0.2 m apart. The flow is forced by a 350 kW fan in the primary circuit, and a 110 kW blower in the secondary circuit. The primary circuit features a factor of four throat reductions, followed by a 1.6 reduction before the test section. Upstream and downstream sensors permit monitoring of the anechoic effectiveness of the channel. Other sensors allow modeling of the flow structures in the tunnel. The tunnel was used to examine turbulent boundary layers in flows up to 140 m/sec, tubulence-excited vibrations in walls, and the effects of laminar and turbulent flows on the appearance and locations of noise sources.

  17. Wire chamber

    DOEpatents

    Atac, Muzaffer

    1989-01-01

    A wire chamber or proportional counter device, such as Geiger-Mueller tube or drift chamber, improved with a gas mixture providing a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor.

  18. IONIZATION CHAMBER

    DOEpatents

    Redman, W.C.; Shonka, F.R.

    1958-02-18

    This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

  19. Ionization chamber

    DOEpatents

    Walenta, Albert H.

    1981-01-01

    An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

  20. Ionization chamber

    DOEpatents

    Walenta, A.H.

    An ionization chamber is described which has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionizes the gas.

  1. Anechoic coatings obtained from two- and three-dimensional monopole resonance diffraction gratings.

    PubMed

    Ivansson, Sven M

    2012-04-01

    Underwater sound reflections can be reduced in magnitude by a rubber coating including three-dimensional (3-D) cavities forming a doubly periodic diffraction grating. A monopole resonance for sphere-like cavities enhances absorption in the surrounding rubber solid. A corresponding resonance for an infinite cylinder is studied in the present paper. Appearing at a considerably lower frequency than for a sphere with the same radius, it suggests the possibility of much thinner anechoic coatings including cylindrical cavities, with axes in a lateral direction, forming a diffraction grating with a single period. This is effectively a 2-D case, because of invariance in the axial direction. Subsequent coating design computations, using the layer-multiple-scattering method and including cavities of different sizes, show improved reflection reduction with coatings only about one third as thick. Still accounting for multiple scattering among the cavities and capturing the essential physics, the monopole approximation is applied to advance the analytic study of the reflection reduction. An energy decomposition relation is derived and used to quantify the absorption of the incident sound energy by cavities of different sizes. Coatings based on filled inclusions and other resonance effects are briefly considered. Again, the 2-D alternative with cylinders of mixed sizes gives thinner coatings.

  2. Chamber B Thermal/Vacuum Chamber: User Test Planning Guide

    NASA Technical Reports Server (NTRS)

    Montz, Mike E.

    2012-01-01

    Test process, milestones and inputs are unknowns to first-time users of Chamber B. The User Test Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their test engineering personnel in test planning and execution. Material covered includes a roadmap of the test process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, test article interfaces, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

  3. Anechoic Sphere Phantoms for Estimating 3-D Resolution of Very High Frequency Ultrasound Scanners

    PubMed Central

    Madsen, Ernest L.; Frank, Gary R.; McCormick, Matthew M.; Deaner, Meagan E.; Stiles, Timothy A.

    2013-01-01

    Two phantoms have been constructed for assessing the performance of high frequency ultrasound imagers. They also allow for periodic quality assurance tests. The phantoms contain eight blocks of tissue-mimicking material where each block contains a spatially random distribution of suitably small anechoic spheres having a small distribution of diameters. The eight mean sphere diameters are distributed from 0.10 to 1.09 mm. The two phantoms differ primarily in terms of the backscatter coefficient of the background material in which the spheres are suspended. The mean scatterer diameter for one phantom is larger than that for the other phantom resulting in a lesser increase in backscatter coefficient for the second phantom; however, the backscatter curves cross at about 35 MHz. Since spheres have no preferred orientation, all three (spatial) dimensions of resolution contribute to sphere detection on an equal basis; thus, the resolution is termed 3-D. Two high frequency scanners are compared. One employs single-element (fixed focus) transducers, and the other employs variable focus linear arrays. The nominal frequency for the single element transducers were 25 and 55 MHz and for the linear array transducers were 20, 30 and 40 MHz. The depth range for detection of spheres of each size is determined corresponding to determination of 3-D resolution as a function of depth. As expected, the single-element transducers are severely limited in useful imaging depth ranges compared with the linear arrays. Note that these phantoms could also be useful for training technicians in using higher frequency scanners. PMID:20889416

  4. Research and test facilities

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A description is given of each of the following Langley research and test facilities: 0.3-Meter Transonic Cryogenic Tunnel, 7-by 10-Foot High Speed Tunnel, 8-Foot Transonic Pressure Tunnel, 13-Inch Magnetic Suspension & Balance System, 14-by 22-Foot Subsonic Tunnel, 16-Foot Transonic Tunnel, 16-by 24-Inch Water Tunnel, 20-Foot Vertical Spin Tunnel, 30-by 60-Foot Wind Tunnel, Advanced Civil Transport Simulator (ACTS), Advanced Technology Research Laboratory, Aerospace Controls Research Laboratory (ACRL), Aerothermal Loads Complex, Aircraft Landing Dynamics Facility (ALDF), Avionics Integration Research Laboratory, Basic Aerodynamics Research Tunnel (BART), Compact Range Test Facility, Differential Maneuvering Simulator (DMS), Enhanced/Synthetic Vision & Spatial Displays Laboratory, Experimental Test Range (ETR) Flight Research Facility, General Aviation Simulator (GAS), High Intensity Radiated Fields Facility, Human Engineering Methods Laboratory, Hypersonic Facilities Complex, Impact Dynamics Research Facility, Jet Noise Laboratory & Anechoic Jet Facility, Light Alloy Laboratory, Low Frequency Antenna Test Facility, Low Turbulence Pressure Tunnel, Mechanics of Metals Laboratory, National Transonic Facility (NTF), NDE Research Laboratory, Polymers & Composites Laboratory, Pyrotechnic Test Facility, Quiet Flow Facility, Robotics Facilities, Scientific Visualization System, Scramjet Test Complex, Space Materials Research Laboratory, Space Simulation & Environmental Test Complex, Structural Dynamics Research Laboratory, Structural Dynamics Test Beds, Structures & Materials Research Laboratory, Supersonic Low Disturbance Pilot Tunnel, Thermal Acoustic Fatigue Apparatus (TAFA), Transonic Dynamics Tunnel (TDT), Transport Systems Research Vehicle, Unitary Plan Wind Tunnel, and the Visual Motion Simulator (VMS).

  5. Chamber propagation

    SciTech Connect

    Langdon, B.

    1991-01-16

    Propagation of a heavy ion beam to the target appears possible under conditions thought to be realizable by several reactor designs. Beam quality at the lens is believed to provide adequate intensity at the target -- but the beam must pass through chamber debris and its self fields along the way. This paper reviews present consensus on propagation modes and presents recent results on the effects of photoionization of the beam ions by thermal x-rays from the heated target. Ballistic propagation through very low densities is a conservative mode. The more-speculative self-pinched mode, at 1 to 10 Torr, offers reactor advantages and is being re-examined by others. 13 refs.

  6. Chamber transport

    SciTech Connect

    OLSON,CRAIG L.

    2000-05-17

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  7. Quality assurance procedures for environmental control and monitoring in plant growth facilities. Report of the North Central Regional 101 Committee on Growth Chamber Use

    NASA Technical Reports Server (NTRS)

    Tibbitts, T. W. (Principal Investigator)

    1986-01-01

    This report includes procedures for ensuring the quality of the environment provided for plant growth in controlled environment facilities. Biologists and engineers may use these procedures for ensuring quality control during experiments or for ensuring quality control in the design of plant growth facilities. Environmental monitoring prior to and during experiments is included in these procedures. Specific recommendations cover control, acquisition, and calibration for sensor types for the separate parameters of radiation (light), temperature, humidity, carbon dioxide, and air movement.

  8. Space Station Live: Historic Vacuum Chamber to Test Webb Telescope

    NASA Video Gallery

    NASA Public Affairs Officer Dan Huot recently visited Johnson Space Center’s 400,000 cubic foot vacuum chamber, Chamber A, and spoke with Mary Cerimele, the lab manager for this historic facility.

  9. 'Flight effect' analysis of turbojet and turbofan nozzle models in the CEPRA 19 anechoic wind tunnel at the CEP

    NASA Astrophysics Data System (ADS)

    Fayot, C.; Gely, D.

    Measurements have been obtained at the Centre d'Essais des Propulseurs CEPRA 19 anechoic wind tunnel using turbojet and turbofan nozzle models in order to study the effect of flight velocity on jet noise. The present results are found to be in good general agreement with both theoretical results and flight test data. It is suggested that noise spectra anomalies noted at frequencies higher than 40 kHz may reflect the passage of sound waves across the mixing zone and/or the turbulent boundary layer which develops along the nozzle fuel line.

  10. A new laboratory facility to study the interactions of aerosols, cloud droplets/ice crystals, and trace gases in a turbulent environment: The Π Chamber

    NASA Astrophysics Data System (ADS)

    Cantrell, W. H., II; Chang, K.; Ciochetto, D.; Niedermeier, D.; Bench, J.; Shaw, R. A.

    2014-12-01

    A detailed understanding of gas-aerosol-cloud interaction within the turbulent atmosphere is of prime importance for an accurate understanding of Earth's climate system. As one example: While every cloud droplet began as an aerosol particle, not every aerosol particle becomes a cloud droplet. The particle to droplet transformation requires that the particle be exposed to some critical concentration of water vapor, which differs for different combinations of particle size and chemical composition. Similarly, the formation of ice particles in mixed phase clouds is also catalyzed by aerosol particles. Even in the simplest scenarios it is challenging to gain a full understanding of the aerosol activation and ice nucleation processes. At least two other factors contribute significantly to the complexity observed in the atmosphere. First, aerosols and cloud particles are not static entities, but are continuously interacting with their chemical environment, and therefore changing in their properties. Second, clouds are ubiquitously turbulent, so thermodynamic and compositional variables, such as water vapor or other trace gas concentrations, fluctuate in space and time. Indeed, the coupling between turbulence and microphysical processes is one of the major research challenges in cloud physics. We have developed a multiphase, turbulent reaction chamber, (dubbed the Π Chamber, after the internal volume of 3.14 cubic meters) designed to address the problems outlined above. It is capable of pressures ranging from sea level to ~ 100 mbar, and can sustain temperatures of +40 to -55 ºC. We can independently control the temperatures on the surfaces of three heat transfer zones. This allows us to establish a temperature gradient between the floor and ceiling inducing Rayleigh-Benard convection and inducing a turbulent environment. Interior surfaces are electropolished stainless steel to facilitate cleaning before and after chemistry experiments. At present, supporting

  11. Equivalent modulus method for finite element simulation of the sound absorption of anechoic coating backed with orthogonally rib-stiffened plate

    NASA Astrophysics Data System (ADS)

    Jin, Zhongkun; Yin, Yao; Liu, Bilong

    2016-03-01

    The finite element method is often used to investigate the sound absorption of anechoic coating backed with orthogonally rib-stiffened plate. Since the anechoic coating contains cavities, the number of grid nodes of a periodic unit cell is usually large. An equivalent modulus method is proposed to reduce the large amount of nodes by calculating an equivalent homogeneous layer. Applications of this method in several models show that the method can well predict the sound absorption coefficient of such structure in a wide frequency range. Based on the simulation results, the sound absorption performance of such structure and the influences of different backings on the first absorption peak are also discussed.

  12. D0 central tracking chamber performance studies

    SciTech Connect

    Pizzuto, D.

    1991-12-01

    The performance of the completed DO central tracking chamber was studied using cosmic rays at the State University of New York at Stony Brook. Also studied was a prototype tracking chamber identical in design to the completed DO tracking chamber. The prototype chamber was exposed to a collimated beam of 150 GeV pions at the Fermilab NWA test facility. Results indicate an R{Phi} tracking resolution compatible with the limitations imposed by physical considerations, excellent 2 track resolution, and a high track reconstruction efficiency along with a good rejection power against {gamma} {yields} e {sup +} e{sup {minus}} events.

  13. Portable Hyperbaric Chamber

    NASA Technical Reports Server (NTRS)

    Schneider, William C. (Inventor); Locke, James P. (Inventor); DeLaFuente, Horacio (Inventor)

    2001-01-01

    A portable, collapsible hyperbaric chamber was developed. A toroidal inflatable skeleton provides initial structural support for the chamber, allowing the attendant and/or patient to enter the chamber. Oval hatches mate against bulkhead rings, and the hyperbaric chamber is pressurized. The hatches seal against an o-ring, and the internal pressure of the chamber provides the required pressure against the hatch to maintain an airtight seal. In the preferred embodiment, the hyperbaric chamber has an airlock to allow the attendant to enter and exit the patient chamber during treatment. Visual communication is provided through portholes in the patient and/or airlock chamber. Life monitoring and support systems are in communication with the interior of the hyperbaric chamber and/or airlock chamber through conduits and/or sealed feed-through connectors into the hyperbaric chamber.

  14. A large hemi-anechoic enclosure for community-compatible aeroacoustic testing of aircraft propulsion systems

    NASA Astrophysics Data System (ADS)

    Cooper, Beth A.

    1993-04-01

    A large hemianechoic (absorptive walls and acoustically hard floor) noise control enclosure was erected around a complex of test stands at the NASA Lewis Research Center in Cleveland, Ohio. This new state-of-the art Aeroacoustic Propulsion Laboratory (APL) provides an all-weather, semi secure test environment while limiting noise to acceptable levels in surrounding residential neighborhoods. The 39.6-m- (130-ft-) diameter geodesic dome houses the new nozzle aeroacoustic test rig (NATR), an ejector-powered Mach 0.3 free jet facility for acoustic testing of supersonic aircraft exhaust nozzles and turbomachinery. A multiaxis, force-measuring, powered lift facility (PLF) stand for testing short takeoff vertical-landing (STOVL) vehicles is also located in the dome. The design of the Aeroacoustic Propulsion Laboratory efficiently accommodates the research functions of two separate test rigs, one of which (NATR) requires a specialized environment for taking acoustic measurements. An absorptive fiberglass wedge treatment on the interior surface of the dome provides a hemianechoic environment for obtaining the accurate acoustic measurements required to meet research program goals. The APL is the first known geodesic dome structure to incorporate transmission-loss properties as well as interior absorption in a free-standing, community-compatible, hemianechoic test facility.

  15. CONTINUOUS ROTATION SCATTERING CHAMBER

    DOEpatents

    Verba, J.W.; Hawrylak, R.A.

    1963-08-01

    An evacuated scattering chamber for use in observing nuclear reaction products produced therein over a wide range of scattering angles from an incoming horizontal beam that bombards a target in the chamber is described. A helically moving member that couples the chamber to a detector permits a rapid and broad change of observation angles without breaching the vacuum in the chamber. Also, small inlet and outlet openings are provided whose size remains substantially constant. (auth)

  16. APS Storage Ring vacuum chamber fabrication

    SciTech Connect

    Goeppner, G.A.

    1990-01-01

    The 1104-m circumference Advanced Photon Source Storage Ring Vacuum System is composed of 240 individual sections, which are fabricated from a combination of aluminum extrusions and machined components. The vacuum chambers will have 3800 weld joints, each subject to strict vacuum requirements, as well as a variety of related design criteria. The vacuum criteria and chamber design are reviewed, including a discussion of the weld joint geometries. The critical fabrication process parameters for meeting the design requirements are discussed. The experiences of the prototype chamber fabrication program are presented. Finally, the required facilities preparation for construction activity is briefly described. 6 refs., 6 figs., 1 tab.

  17. Two chamber reaction furnace

    DOEpatents

    Blaugher, R.D.

    1998-05-05

    A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  18. Two chamber reaction furnace

    DOEpatents

    Blaugher, Richard D.

    1998-05-05

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  19. Stove with multiple chambers

    SciTech Connect

    Black, A.

    1987-04-21

    A stove is described for burning a solid fuel such as wood. The wall means defines a main air inlet, a combustion gas outlet, and four chambers through which gas passes sequentially from the main air inlet to the combustion gas outlet. The chambers comprises a pre-heat plenum chamber into which the main air inlet opens. A main combustion chamber contains solid fuel to be burned into which gas passes from the pre-heat plenum chamber, a second combustion chamber which is downstream of the main combustion chamber with respect to the flow of gas from the main air inlet to the combustion gas outlet, and a third combustion chamber from which the combustion gas outlet opens. The stove also comprises a plate having a restricted opening for providing communication between the second and third combustion chambers. And a catalytic converter comprises a body of solid material formed with passageways, the body of solid material being fitted in the restricted opening so that gas passes from the second combustion chamber to the third combustion chamber by way of the passageways in the body.

  20. BOREAS TGB-1 NSA SF6 Chamber Flux Data

    NASA Technical Reports Server (NTRS)

    Crill, Patrick; Varner, Ruth K.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-1 team made several chamber and tower measurements of trace gases at sites in the BOREAS NSA. This data set contains sulfur hexafluoride (SF6) dark chamber flux measurements at the NSA-OJP and NSA-YJP sites from 16-May through 13-Sep-1994. Gas samples were extracted approximately every 7 days from dark chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  1. Target chambers for gammashpere

    SciTech Connect

    Carpenter, M.P.; Falout, J.W.; Nardi, B.G.

    1995-08-01

    One of our responsibilities for Gammasphere, was designing and constructing two target chambers and associated beamlines to be used with the spectrometer. The first chamber was used with the early implementation phase of Gammasphere, and consisted of two spun-Al hemispheres welded together giving a wall thickness of 0.063 inches and a diameter of 12 inches.

  2. Static diffusion cloud chambers

    NASA Technical Reports Server (NTRS)

    Ayers, G.

    1981-01-01

    The chamber geometry and optical arrangement are described. The supersaturation range is given and consists of readings taken at five fixed points: 0.25%, 0.5%, 0.75%, 1.0%, and 1.25%. The detection system is described including light source, cameras, and photocell detectors. The temperature control and the calibration of the chamber are discussed.

  3. A soundproof pressure chamber.

    PubMed

    Kitahara, M; Kodama, A; Ozawa, H; Inoue, S

    1994-01-01

    For neurotological research we designed a soundproof pressure chamber in which pressure can be adjusted +/- 1000 mmH2O at the rate of less than 100 mmH2O per second. Noise in the chamber can be maintained under 30-35 dB while pressure is kept at a given level.

  4. The Mobile Chamber

    NASA Technical Reports Server (NTRS)

    Scharfstein, Gregory; Cox, Russell

    2012-01-01

    A document discusses a simulation chamber that represents a shift from the thermal-vacuum chamber stereotype. This innovation, currently in development, combines the capabilities of space simulation chambers, the user-friendliness of modern-day electronics, and the modularity of plug-and-play computing. The Mobile Chamber is a customized test chamber that can be deployed with great ease, and is capable of bringing payloads at temperatures down to 20 K, in high vacuum, and with the desired metrology instruments integrated to the systems control. Flexure plans to lease Mobile Chambers, making them affordable for smaller budgets and available to a larger customer base. A key feature of this design will be an Apple iPad-like user interface that allows someone with minimal training to control the environment inside the chamber, and to simulate the required extreme environments. The feedback of thermal, pressure, and other measurements is delivered in a 3D CAD model of the chamber's payload and support hardware. This GUI will provide the user with a better understanding of the payload than any existing thermal-vacuum system.

  5. High resolution drift chambers

    SciTech Connect

    Va'vra, J.

    1985-07-01

    High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

  6. Evaluation of Carbon Dioxide Dissipation within a Euthanasia Chamber

    PubMed Central

    Djoufack-Momo, Shelly M; Amparan, Ashlee A; Grunden, Beverly; Boivin, Gregory P

    2014-01-01

    CO2 euthanasia is used widely for small laboratory animals, such as rodents. A common necessity in many animal research facilities is to euthanize mice in sequential batches. We assessed the effects of several variables on the time it took for CO2 to dissipate within a chamber. Using standard euthanasia time, changes in flow rate were compared between a slow 15% fill rate for 7 min, and a slow 15% followed by a rapid 50% filling for a total of 5 min. Additional variables assessed included the effects of opening the lid after the completion of chamber filling, turning the chamber over after completion of filling, and the use and removal of a cage from within the chamber. For all trials, CO2 levels in the chambers peaked between 50% and 80%. After the gas was turned off, the concentration of CO2 dropped to below 10% CO2 within 2 min, except when the lid was left on the chamber, where concentration levels remained above 10% after 20 min. CO2 dissipation was significantly faster when the chamber was turned upside down after filling. Significant interaction effects occurred among the factors of cage presence within the chamber, flow rate, and chamber position. Only leaving the lid on the chamber had any practical implication for delaying CO2 dissipation. We recommend that users allow 2 min for CO2 to clear from the chamber before subsequent euthanasia procedures, unless the chamber is manipulated to increase the dissipation rate. PMID:25199098

  7. 16. NBS TOPSIDE CONTROL ROOM, THE NBS HYPERBARIC CHAMBER IS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. NBS TOPSIDE CONTROL ROOM, THE NBS HYPERBARIC CHAMBER IS VERY CLOSE TO THE WATER'S EDGE AND HERE FOR DIVER EMERGENCY SUPPORT. A MEDICAL STAFF IS LOCATED ON THE MARSHALL SPACE FLIGHT CENTER (MSFC) AND SUPPORTS THE NBS PERSONNEL WHEN HYPERBARIC CHAMBER OPERATION IS NECESSARY. - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

  8. 45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), VIEW LOOKING EAST. LEAD ENCLOSED PIPING IS DRAIN FROM BOILER CHAMBER No. 1 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  9. Acoustic-Levitation Chamber

    NASA Technical Reports Server (NTRS)

    Barmatz, M. B.; Granett, D.; Lee, M. C.

    1984-01-01

    Uncontaminated environments for highly-pure material processing provided within completely sealed levitation chamber that suspends particles by acoustic excitation. Technique ideally suited for material processing in low gravity environment of space.

  10. The Mars Chamber

    NASA Video Gallery

    The Mars chamber is a box about the size of a refrigerator that re-creates the temperatures, pressures, and atmosphere of the Martian surface, essentially creating a Mars environment on Earth! Scie...

  11. Sleeve reaction chamber system

    DOEpatents

    Northrup, M. Allen; Beeman, Barton V.; Benett, William J.; Hadley, Dean R.; Landre, Phoebe; Lehew, Stacy L.; Krulevitch, Peter A.

    2009-08-25

    A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

  12. Solar thermal plasma chamber

    NASA Astrophysics Data System (ADS)

    Bonometti, Joseph; Buchele, Donald R.; Castle, Charles H.; Gregory, Don A.

    2001-11-01

    A unique solar thermal chamber has been designed and fabricated to produce the maximum concentration of solar energy and highest temperature possible. Its primary purpose was for solar plasma propulsion experiments and related material specimen testing above 3000 Kelvin. The design not only maximized solar concentration, but also, minimized infrared heat loss. This paper provides the underlining theory and operation of the chamber and initial optical correlation to the actual fabricated hardware. The chamber is placed at the focal point of an existing primary concentrator with a 2.74-meter (9 foot) focal length. A quartz lens focuses a smaller sun image at the inlet hole of the mirrored cavity. The lens focuses two image planes at prescribed positions; the sun at the cavity's entrance hole, and the primary concentrator at the junction plane of two surfaces that form the cavity chamber. The back half is an ellipsoid reflector that produces a 1.27 cm diameter final sun image. The image is 'suspended in space' 7.1cm away from the nearest cavity surface, to minimize thermal and contaminate damage to the mirror surfaces. A hemisphere mirror makes up the front chamber and has its center of curvature at the target image, where rays leaving the target are reflected back upon themselves, minimizing radiation losses.

  13. Improved Rhenium Thrust Chambers

    NASA Technical Reports Server (NTRS)

    O'Dell, John Scott

    2015-01-01

    Radiation-cooled bipropellant thrust chambers are being considered for ascent/ descent engines and reaction control systems on various NASA missions and spacecraft, such as the Mars Sample Return and Orion Multi-Purpose Crew Vehicle (MPCV). Currently, iridium (Ir)-lined rhenium (Re) combustion chambers are the state of the art for in-space engines. NASA's Advanced Materials Bipropellant Rocket (AMBR) engine, a 150-lbf Ir-Re chamber produced by Plasma Processes and Aerojet Rocketdyne, recently set a hydrazine specific impulse record of 333.5 seconds. To withstand the high loads during terrestrial launch, Re chambers with improved mechanical properties are needed. Recent electrochemical forming (EL-Form"TM") results have shown considerable promise for improving Re's mechanical properties by producing a multilayered deposit composed of a tailored microstructure (i.e., Engineered Re). The Engineered Re processing techniques were optimized, and detailed characterization and mechanical properties tests were performed. The most promising techniques were selected and used to produce an Engineered Re AMBR-sized combustion chamber for testing at Aerojet Rocketdyne.

  14. Drift Chamber Experiment

    NASA Astrophysics Data System (ADS)

    Walenta, A. H.; ćonka Nurdan, T.

    2003-07-01

    This paper describes a laboratory course held at ICFA 2002 Regional Instrumentation School in Morelia, Mexico. This course intends to introduce drift chambers, which play an important role in particle physics experiments as tracking detectors. The experimental setup consists of a single-sided, single-cell drift chamber, a plastic scintillator detector and a collimated 90Sr source. The measurements on the drift velocity of electrons, its change as a function of a drift field, gas gain and diffusion are performed at this laboratory course.

  15. Electrostatic Levitator Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Optical ports ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (beam passes through the window at left), positioning lasers (one port is at center), and lamps to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

  16. Internal combustion chamber

    SciTech Connect

    Schmitz, D.L.

    1988-03-08

    In combination with a high-powered reciprocating piston internal combustion engine, an internal combustion cylinder assembly is described comprising: a cylinder head made of weldable material; a cylinder liner for containing and guiding a reciprocating piston of the engine, a coolant jacket adapted to receive a cooling fluid, mounted on and surrounding the cylinder liner, the jacket being attached to the cylinder head and detachably supported by the cylinder liner, and forming a cooling chamber around the cylinder liner; means to supply the cooling fluid to the cooling chamber and to discharge the cooling fluid therefrom.

  17. Filament wound rocket motor chambers

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The design, analysis, fabrication and testing of a Kevlar-49/HBRF-55A filament wound chamber is reported. The chamber was fabricated and successfully tested to 80% of the design burst pressure. Results of the data reduction and analysis from the hydrotest indicate that the chamber design and fabrication techniques used for the chamber were adequate and the chamber should perform adequately in a static test.

  18. Automated soil gas monitoring chamber

    DOEpatents

    Edwards, Nelson T.; Riggs, Jeffery S.

    2003-07-29

    A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural microclimate within the chamber has been invented. The chamber opens between measurements and therefore does not alter the metabolic processes that influence soil gas efflux rates. A multiple chamber system provides for repetitive multi-point sampling, undisturbed metabolic soil processes between sampling, and an essentially airtight sampling chamber operating at ambient pressure.

  19. Ultrasonic Drying Processing Chamber

    NASA Astrophysics Data System (ADS)

    Acosta, V.; Bon, J.; Riera, E.; Pinto, A.

    The design of a high intensity ultrasonic chamber for drying process was investigated. The acoustic pressure distribution in the ultrasonic drying chamber was simulated solving linear elastic models with attenuation for the acoustic-structure interaction. Together with the government equations, the selection of appropriate boundary conditions, mesh refinement, and configuration parameters of the calculation methods, which is of great importance to simulate adequately the process, were considered. Numerical solution, applying the finite element method (FEM), of acoustic-structure interactions involves to couple structural and fluid elements (with different degrees of freedom), whose solution implies several problems of hardware requirements and software configuration, which were solved. To design the drying chamber, the influence of the directivity of the drying open camera and the staggered reflectors over the acoustic pressure distribution was analyzed. Furthermore, to optimize the influence of the acoustic energy on the drying process, the average value of the acoustic energy distribution in the drying chamber was studied. This would determine the adequate position of the food samples to be dried. For this purpose, the acoustic power absorbed by the samples will be analyzed in later studies.

  20. Flame-Test Chamber

    NASA Technical Reports Server (NTRS)

    Bjorklund, R. A.

    1984-01-01

    Experimental chamber provides controlled environment for observation and measurement of flames propagating in expanding plume of flammable air/fuel mixture under atmospheric conditions. Designed to evaluate quenching capability of screen-type flame arresters in atmospheric vents of fuel cargo tanks aboard marine cargo vessels.

  1. Improved wire chamber

    DOEpatents

    Atac, M.

    1987-05-12

    An improved gas mixture for use with proportional counter devices, such as Geiger-Mueller tubes and drift chambers. The improved gas mixture provides a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor. 2 figs.

  2. Review of straw chambers

    SciTech Connect

    Toki, W.H.

    1990-03-01

    This is a review of straw chambers used in the HRS, MAC, Mark III, CLEO, AMY, and TPC e{sup +}e{sup {minus}} experiments. The straws are 6--8 mm in diameter, operate at 1--4 atmospheres and obtain resolutions of 45--100 microns. The designs and constructions are summarized and possible improvements discussed.

  3. Liquid Wall Chambers

    SciTech Connect

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  4. A comparison of the acoustic and aerodynamic measurements of a model rotor tested in two anechoic wind tunnels

    NASA Technical Reports Server (NTRS)

    Boxwell, D. A.; Schmitz, F. H.; Splettstoesser, W. R.; Schultz, K. J.; Lewy, S.; Caplot, M.

    1986-01-01

    Two aeroacoustic facilities--the CEPRA 19 in France and the DNW in the Netherlands--are compared. The two facilities have unique acoustic characteristics that make them appropriate for acoustic testing of model-scale helicopter rotors. An identical pressure-instrumented model-scale rotor was tested in each facility and acoustic test results are compared with full-scale-rotor test results. Blade surface pressures measured in both tunnels were used to correlated nominal rotor operating conditions in each tunnel, and also used to assess the steadiness of the rotor in each tunnel's flow. In-the-flow rotor acoustic signatures at moderate forward speeds (35-50 m/sec) are presented for each facility and discussed in relation to the differences in tunnel geometries and aeroacoustic characteristics. Both reports are presented in appendices to this paper. ;.);

  5. A comparison of the acoustic and aerodynamic measurements of a model rotor tested in two anechoic wind tunnels

    NASA Technical Reports Server (NTRS)

    Boxwell, D. A.; Schmitz, F. H.; Splettstoesser, W. R.; Schultz, K. J.; Lewy, S.

    1986-01-01

    Two aeroacoustic facilities - the CEPRA 19 in France and the DNW in the Netherlands - are compared. The two facilities have unique acoustic characteristics that make them appropriate for acoustic testing of model-scale helicopter rotors. An identical pressure-instrumented model-scale rotor was tested in each facility and acoustic test results are compared with full-scale-rotor test results. Blade surface pressures measured in both tunnels were used to correlated nominal rotor operating conditions in each tunnel, and also used to assess the steadiness of the rotor in each tunnel's flow. In-the-flow rotor acoustic signatures at moderate forward speeds (35-50 m/sec) are presented for each facility and discussed in relation to the differences in tunnel geometries and aeroacoustic characteristics. Both reports are presented in appendices to this paper.

  6. Multi-chamber deposition system

    DOEpatents

    Jacobson, Richard L.; Jeffrey, Frank R.; Westerberg, Roger K.

    1989-10-17

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  7. Multi-chamber deposition system

    DOEpatents

    Jacobson, Richard L.; Jeffrey, Frank R.; Westerberg, Roger K.

    1989-06-27

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  8. 44. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION CCC), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION CCC), LOOKING NORTHEAST SHOWING DRAIN PIPE FROM SUMP - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  9. 61. BOILER CHAMBER No. 2, LOOKING SOUTHWEST BETWEEN CHAMBER AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. BOILER CHAMBER No. 2, LOOKING SOUTHWEST BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION PPP) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  10. 41. AUXILIARY CHAMBER, CONCRETE ENCLOSURE CHAMBER AIR LOCK (EXTERIOR), LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. AUXILIARY CHAMBER, CONCRETE ENCLOSURE CHAMBER AIR LOCK (EXTERIOR), LOOKING NORTHEAST FROM SOUTHWEST CORNER (LOCATION AAA) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  11. 50. BOILER CHAMBER No. 1, LOOKING SOUTHEAST BETWEEN CHAMBER AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. BOILER CHAMBER No. 1, LOOKING SOUTHEAST BETWEEN CHAMBER AND ENCLOSURE (LOCATION III) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  12. 72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR AND CANAL (LOCATION T) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  13. Terminal configured vehicle program: Test facilities guide

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The terminal configured vehicle (TCV) program was established to conduct research and to develop and evaluate aircraft and flight management system technology concepts that will benefit conventional take off and landing operations in the terminal area. Emphasis is placed on the development of operating methods for the highly automated environment anticipated in the future. The program involves analyses, simulation, and flight experiments. Flight experiments are conducted using a modified Boeing 737 airplane equipped with highly flexible display and control equipment and an aft flight deck for research purposes. The experimental systems of the Boeing 737 are described including the flight control computer systems, the navigation/guidance system, the control and command panel, and the electronic display system. The ground based facilities used in the program are described including the visual motion simulator, the fixed base simulator, the verification and validation laboratory, and the radio frequency anechoic facility.

  14. Three chamber negative ion source

    DOEpatents

    Leung, Ka-Ngo; Ehlers, Kenneth W.; Hiskes, John R.

    1985-01-01

    A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

  15. Multiwire proportional chamber development

    NASA Technical Reports Server (NTRS)

    Doolittle, R. F.; Pollvogt, U.; Eskovitz, A. J.

    1973-01-01

    The development of large area multiwire proportional chambers, to be used as high resolution spatial detectors in cosmic ray experiments is described. A readout system was developed which uses a directly coupled, lumped element delay-line whose characteristics are independent of the MWPC design. A complete analysis of the delay-line and the readout electronic system shows that a spatial resolution of about 0.1 mm can be reached with the MWPC operating in the strictly proportional region. This was confirmed by measurements with a small MWPC and Fe-55 X-rays. A simplified analysis was carried out to estimate the theoretical limit of spatial resolution due to delta-rays, spread of the discharge along the anode wire, and inclined trajectories. To calculate the gas gain of MWPC's of different geometrical configurations a method was developed which is based on the knowledge of the first Townsend coefficient of the chamber gas.

  16. CONTINUOUSLY SENSITIVE BUBBLE CHAMBER

    DOEpatents

    Good, R.H.

    1959-08-18

    A radiation detector of the bubble chamber class is described which is continuously sensitive and which does not require the complex pressure cycling equipment characteristic of prior forms of the chamber. The radiation sensitive element is a gas-saturated liquid and means are provided for establishing a thermal gradient across a region of the liquid. The gradient has a temperature range including both the saturation temperature of the liquid and more elevated temperatures. Thus a supersaturated zone is created in which ionizing radiations may give rise to visible gas bubbles indicative of the passage of the radiation through the liquid. Additional means are provided for replenishing the supply of gas-saturated liquid to maintaincontinuous sensitivity.

  17. Electrostatic Levitator Vacuum Chambers

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Optical prots ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (the beam passes through the window at left), poisitioning lasers (one port is at center), and lamps (such as the deuterium arc lamp at right), and to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

  18. Electrostatic Levitator Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Optical prots ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (the beam passes through the window at left), poisitioning lasers (one port is at center), and lamps (arc lamp at right), and to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

  19. Electrostatic Levitator Vaccum Chamber

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Optical ports ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (the beam passes through the window at left), positioning lasers (one port is at center), and lamps (such as the deuterium arc lamp at right), and to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

  20. Vacuum Chamber Design of NSLS-II Storage Ring

    SciTech Connect

    Doom,L.; Ferreira, M.; Hseuh, H. C.; Lincoln, F.; Longo, C.; Ravindranath, V.; Sharma, S.

    2008-06-11

    National Synchrotron Light Source II (NSLS II) will be a 3-GeV, 792-meter circumference, 3rd generation synchrotron radiation facility, with ultra low emittance and extremely high brightness. the storage ring has 30 Double-Bend-Achromatic (DBA) cells. in each cell, there are five magnets and chamber girders, and one straight section for insertion devices or Radio Frequency (RF) cavities or injection. Most vacuum chambers are made from extruded aluminum with two different cross sections: one fitted in the dipole magnets, and the other surrounded by multipole magnets. They discuss the layout of the DBA cells, the detailed design of the cell's vacuum chambers, the mounting of the Beam-Position-Monitor (BPM) buttons, discrete absorbers, lumped pumps and the distributed Non-Evaporable Getter (NEG) strips, and describe the fabrication and testing of these prototype cell chambers. The account also details the development of the chamber bakeout process, the NEG stri's supports, and the RF shielded bellows.

  1. Calibration of PICO Bubble Chamber Dark Matter Detectors

    NASA Astrophysics Data System (ADS)

    Jin, Miaotianzi; PICO Collaboration

    2016-03-01

    The PICO Collaboration builds bubble chambers for the direct detection of WIMP dark matter. I will present the suite of calibration experiments performed to measure the sensitivity of these chambers to nuclear recoils (the expected WIMP signal) and to gamma rays (a common background to the WIMP signal). These calibrations include measurements with a 10-ml C3F8 bubble chamber at Northwestern University and with a 30-ml C3F8 bubble chamber deployed in the University of Montreal's tandem Van de Graaf facility, giving the bubble chamber response to a variety of gamma rays, broad-spectrum neutron sources, and mono-energetic low energy neutrons. I will compare our measured sensitivities to those predicted by a simple thermodynamic model and will show how the results impact our ability to detect dark matter, with a focus on light WIMP searches. Supported by DOE Grant: DE-SC0012161.

  2. Using the Nova target chamber for high-yield targets

    SciTech Connect

    Pitts, J.H.

    1987-09-28

    The existing 2.2-m-radius Nova aluminum target chamber, coated and lined with boron-seeded carbon shields, is proposed for use with 1000-MJ-yield targets in the next laser facility. The laser beam and diagnostic holes in the target chamber are left open and the desired 10/sup -2/ Torr vacuum is maintained both inside and outside the target chamber; a larger target chamber room is the vacuum barrier to the atmosphere. The hole area available is three times that necessary to maintain a maximum fluence below 12 J/cm/sup 2/ on optics placed at a radius of 10 m. Maximum stress in the target chamber wall is 73 MPa, which complies with the intent of the ASME Pressure Vessel Code. However, shock waves passing through the inner carbon shield could cause it to comminute. We propose tests and analyses to ensure that the inner carbon shield survives the environment. 13 refs.

  3. Vibrating-chamber levitation systems

    NASA Technical Reports Server (NTRS)

    Barmatz, M. B.; Granett, D.; Lee, M. C. (Inventor)

    1985-01-01

    Systems are described for the acoustic levitation of objects, which enable the use of a sealed rigid chamber to avoid contamination of the levitated object. The apparatus includes a housing forming a substantially closed chamber, and means for vibrating the entire housing at a frequency that produces an acoustic standing wave pattern within the chamber.

  4. Vertical two chamber reaction furnace

    DOEpatents

    Blaugher, Richard D.

    1999-03-16

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  5. Vertical two chamber reaction furnace

    DOEpatents

    Blaugher, R.D.

    1999-03-16

    A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  6. Vibrating-chamber levitation systems

    NASA Astrophysics Data System (ADS)

    Barmatz, M. B.; Granett, D.; Lee, M. C.

    1985-10-01

    Systems are described for the acoustic levitation of objects, which enable the use of a sealed rigid chamber to avoid contamination of the levitated object. The apparatus includes a housing forming a substantially closed chamber, and means for vibrating the entire housing at a frequency that produces an acoustic standing wave pattern within the chamber.

  7. Multi-anode ionization chamber

    DOEpatents

    Bolotnikov, Aleksey E.; Smith, Graham; Mahler, George J.; Vanier, Peter E.

    2010-12-28

    The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

  8. Ionization chamber dosimeter

    DOEpatents

    Renner, Tim R.; Nyman, Mark A.; Stradtner, Ronald

    1991-01-01

    A method for fabricating an ion chamber dosimeter collecting array of the type utilizing plural discrete elements formed on a uniform collecting surface which includes forming a thin insulating layer over an aperture in a frame having surfaces, forming a predetermined pattern of through holes in the layer, plating both surfaces of the layer and simultaneously tilting and rotating the frame for uniform plate-through of the holes between surfaces. Aligned masking and patterned etching of the surfaces provides interconnects between the through holes and copper leads provided to external circuitry.

  9. Review of wire chamber aging

    SciTech Connect

    Va'Vra, J.

    1986-02-01

    This paper makes an overview of the wire chamber aging problems as a function of various chamber design parameters. It emphasizes the chemistry point of view and many examples are drawn from the plasma chemistry field as a guidance for a possible effort in the wire chamber field. The paper emphasizes the necessity of variable tuning, the importance of purity of the wire chamber environment, as well as it provides a practical list of presently known recommendations. In addition, several models of the wire chamber aging are qualitatively discussed. The paper is based on a summary talk given at the Wire Chamber Aging Workshop held at LBL, Berkeley on January 16-17, 1986. Presented also at Wire Chamber Conference, Vienna, February 25-28, 1986. 74 refs., 18 figs., 11 tabs.

  10. Diogene pictorial drift chamber

    SciTech Connect

    Gosset, J.

    1984-01-01

    A pictorial drift chamber, called DIOGENE, has been installed at Saturne in order to study central collisions of high energy heavy ions. It has been adapted from the JADE internal detector, with two major differences to be taken into account. First, the center-of-mass of these collisions is not identical to the laboratory reference frame. Second, the energy loss and the momentum ranges of the particles to be detected are different from the ones in JADE. It was also tried to keep the cost as small as possible, hence the choice of minimum size and minimum number of sensitive wires. Moreover the wire planes are shifted from the beam axis: this trick helps very much to quickly reject the bad tracks caused by the ambiguity of measuring drift distances (positive or negative) through times (always positive).

  11. Mush Column Magma Chambers

    NASA Astrophysics Data System (ADS)

    Marsh, B. D.

    2002-12-01

    Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior

  12. Environmental calibration chamber operations

    NASA Technical Reports Server (NTRS)

    Lester, D. L.

    1988-01-01

    Thermal vacuum capabilities are provided for the development, calibration, and functional operation checks of flight sensors, sources, and laboratory and field instruments. Two systems are available. The first is a 46 cm diameter diffusion pumped vacuum chambler of the bell jar variety. It has an internal thermal shroud, LN2 old trap, two viewing ports, and various electrical and fluid feedthroughs. The other, also an oil diffusion pumped system, consists of a 1.8 m diameter by 2.5 m long stainless steel vacuum tank, associated pumping and control equipment, a liquid nitrogen storage and transfer system and internal IR/visible calibration sources. This is a two story system with the chamber located on one floor and the pumping/cryogenic systems located on the floor below.

  13. Diogene pictorial drift chamber

    NASA Astrophysics Data System (ADS)

    Gosset, J.

    1984-02-01

    A pictorial drift chamber, called DIOGENE, has been installed at Saturne in order to study central collisions of high energy heavy ions. It has been adapted from the JADE internal detector, with two major differences to be taken into account. First, the center-of-mass of these collisions is not identical to the laboratory reference frame. Second, the energy loss and the momentum ranges of the particles to be detected are different from the ones in JADE. It was also tried to keep the cost as small as possible, hence the choice of minimum size and minimum number of sensitive wires. Moreover the wire planes are shifted from the beam axis: this trick helps very much to quickly reject the bad tracks caused by the ambiguity of measuring drift distances (positive or negative) through times (always positive).

  14. National Ignition Facility system design requirements conventional facilities SDR001

    SciTech Connect

    Hands, J.

    1996-04-09

    This System Design Requirements (SDR) document specifies the functions to be performed and the minimum design requirements for the National Ignition Facility (NIF) site infrastructure and conventional facilities. These consist of the physical site and buildings necessary to house the laser, target chamber, target preparation areas, optics support and ancillary functions.

  15. Initial Back-to-Back Fission Chamber Testing in ATRC

    SciTech Connect

    Benjamin Chase; Troy Unruh; Joy Rempe

    2014-06-01

    Development and testing of in-pile, real-time neutron sensors for use in Materials Test Reactor experiments is an ongoing project at Idaho National Laboratory. The Advanced Test Reactor National Scientific User Facility has sponsored a series of projects to evaluate neutron detector options in the Advanced Test Reactor Critical Facility (ATRC). Special hardware was designed and fabricated to enable testing of the detectors in the ATRC. Initial testing of Self-Powered Neutron Detectors and miniature fission chambers produced promising results. Follow-on testing required more experiment hardware to be developed. The follow-on testing used a Back-to-Back fission chamber with the intent to provide calibration data, and a means of measuring spectral indices. As indicated within this document, this is the first time in decades that BTB fission chambers have been used in INL facilities. Results from these fission chamber measurements provide a baseline reference for future measurements with Back-to-Back fission chambers.

  16. HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF PLENUM WITH ATTACHED DRAFT REGULATOR. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  17. EVA Training and Development Facilities

    NASA Technical Reports Server (NTRS)

    Cupples, Scott

    2016-01-01

    Overview: Vast majority of US EVA (ExtraVehicular Activity) training and EVA hardware development occurs at JSC; EVA training facilities used to develop and refine procedures and improve skills; EVA hardware development facilities test hardware to evaluate performance and certify requirement compliance; Environmental chambers enable testing of hardware from as large as suits to as small as individual components in thermal vacuum conditions.

  18. A hyperbaric oxygen chamber for animal experimental purposes.

    PubMed

    Djasim, U M; Spiegelberg, L; Wolvius, E B; van der Wal, K G H

    2012-02-01

    Facilities for hyperbaric oxygen therapy that are suitable for animal experimental research are scarce. In this paper, the authors introduce a hyperbaric oxygen chamber that was developed specifically for animal experimental purposes. The hyperbaric oxygen chamber was designed to meet a number of criteria regarding safety and ease of use. The hyperbaric oxygen chamber conforms to 97/23/EC (Pressure Equipment Directive), Conformity Assessment Module G Product Group 1. It provides easy access, and can be run in manual mode, semi-automatic mode and full-automatic mode. Sensors for pressure level, oxygen level, temperature, humidity and carbon dioxide level allow full control. This state-of-the-art hyperbaric oxygen chamber for animal experimental purposes permits the investigation of the biological mechanisms through which hyperbaric oxygen therapy acts at a fundamental level.

  19. Coating experiment with 1.6-m vacuum evaporation chamber

    NASA Astrophysics Data System (ADS)

    Kamata, Yukiko; Hayashi, Saeko S.; Noguchi, Takeshi; Kanzawa, Tomio; Sasaki, Goro; Torii, Yasuo; Yutani, Masami; Ishikawa, Tsuyoshi

    1998-08-01

    We have conducted a series of coating experiments using the newly installed 1.6 m evaporation chamber at the Advanced Technology Center (ATC) of the National Astronomical Observatory of Japan. The main task of this chamber is to re-aluminize the 1.6 m mirror of the Infrared Simulator at the ATC. The design concept of the 1.6 m chamber is basically the same with the 8.3 m coating facility for Subaru Telescope. Therefore, we could utilize this chamber to evaluate the fundamental performance of the larger chamber. The extensive coating experiments were done in the spring, autumn of 1996, and autumn of 1997. Reduction of the number of the filaments has lead to the increase in their size, which caused difficulty in the annealing process. Attempts are focused on securing the sufficient metal loads on the filaments. Then the filaments are fired to measure the spray pattern of a single filament exposure, or the uniformity pattern resulted from the full setup of filament arrays. Using small slide glasses, the important parameters of the resultant reflecting film that are the thickness, the uniformity of the thickness, and the spectroscopic reflectance are measured. The absolute value of the reflectivity is estimated to be around 91% immediately after opening the chamber. In order to cover a wide range of observing wavelengths for the Infrared Simulator, and eventually for the optical-IR Subaru Telescope, it is necessary to seek after a higher evaporation rate with these chambers.

  20. ECRB REFUGE CHAMBER

    SciTech Connect

    J. W. Keifer

    2001-12-03

    The purpose of this calculation is to identify the initial design requirements for refuge stations, including the client requirements, standards, codes, laws, and regulations, general discipline design criteria, and design basis events and hazards. The scope of this document is for the specific task of designing and constructing refuge stations in the Enhanced Characterization Repository Block (ECRB) subsurface openings as necessary personnel safety enhancements to the current construction, maintenance and testing operations. This document is for the construction at the Exploratory Site Facility (ESF). The criteria is not intended to be incorporated into the proposed repository design and does not support Site Recommendation or License Application efforts. This calculation is prepared in accordance with N-3.12Q as a field support calculation and was prepared using the ''Technical Work Plan for Test Facilities Design FY01 Work Activities'' (TWP) (CRWMS M&O 2000b).

  1. A compact Time Projection Chamber for the Crystal Ball

    NASA Astrophysics Data System (ADS)

    Steffen, O.; Wolfes, M.; Gradl, W.

    2016-07-01

    We report on a development of a compact Time Projection Chamber with triple Gas Electron Multiplier readout to replace the current tracking detector in the Crystal Ball/TAPS Experiment at the A2 Tagged Photon Facility at MAMI in Mainz, Germany. Challenges are the limitations in size and the absence of a longitudinal magnetic flied.

  2. 13. VIEW OF VACUUM CHAMBER AND WELDING EQUIPMENT IN MODULE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. VIEW OF VACUUM CHAMBER AND WELDING EQUIPMENT IN MODULE E. PARTS WERE WELDED UNDER A VACUUM TO PREVENT CORROSION. (11/6/73) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO

  3. 14. VIEW OF VACUUM COATING CHAMBER. THE SYSTEM USED TITANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. VIEW OF VACUUM COATING CHAMBER. THE SYSTEM USED TITANIUM VAPORS TO DEPOSIT TITANIUM COATING ONTO URANIUM PARTS UNDER A VACUUM. (1/11/83) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  4. Overview of the ICF 1000 MJ experiment chamber design

    SciTech Connect

    Slaughter, D.

    1988-09-23

    A conceptual design of an experiment chamber for a high gain ICF facility (1000 MJ) is being developed. Performance goals have been established. Several design approaches are being evaluated through computer simulation, engineering analysis, and experimental testing of candidate first wall components. 10 refs., 3 figs.

  5. Automated protein crystal growth facility

    NASA Technical Reports Server (NTRS)

    Donald, Stacey

    1994-01-01

    A customer for the protein crystal growth facility fills the specially designed chamber with the correct solutions, fills the syringes with their quenching solutions, and submits the data needed for the proper growth of their crystal. To make sure that the chambers and syringes are filled correctly, a NASA representative may assist the customer. The data needed is the approximate growth time, the growth temperature, and the desired crystal size, but this data can be changed anytime from the ground, if needed. The chambers are gathered and placed into numbered slots in special drawers. Then, data is entered into a computer for each of the chambers. Technicians map out when each chamber's growth should be activated so that all of the chambers have enough time to grow. All of this data is up-linked to the space station when the previous growth session is over. Anti-vibrational containers need to be constructed for the high forces encountered during the lift off and the landing of the space shuttle, and though our team has not designed these containers, we do not feel that there is any reason why a suitable one could not be made. When the shuttle reaches the space station, an astronaut removes a drawer of quenched chambers from the growth facility and inserts a drawer of new chambers. All twelve of the drawers can be replaced in this fashion. The optical disks can also be removed this way. The old drawers are stored for the trip back to earth. Once inside the growth facility, a chamber is removed by the robot and placed in one of 144 active sites at a time previously picked by a technician. Growth begins when the chamber is inserted into an active site. Then, the sensing system starts to determine the size of the protein crystal. All during the crystal's growth, the customer can view the crystal and read all of the crystal's data, such as growth rate and crystal size. When the sensing system determines that the crystal has reached the predetermined size, the robot is

  6. LRL 25-inch Bubble Chamber

    DOE R&D Accomplishments Database

    Alvarez, L. W.; Gow, J. D.; Barrera, F.; Eckman, G.; Shand, J.; Watt, R.; Norgren, D.; Hernandez, H. P.

    1964-07-08

    The recently completed 25-inch hydrogen bubble chamber combines excellent picture quality with a fast operating cycle. The chamber has a unique optical system and is designed to take several pictures each Bevatron pulse, in conjunction with the Bevatron rapid beam ejection system.

  7. Fast-response cloud chamber

    NASA Technical Reports Server (NTRS)

    Fogal, G. L.

    1977-01-01

    Wall structure keeps chambers at constant, uniform temperature, yet allows them to be cooled rapidly if necessary. Wall structure, used in fast-response cloud chamber, has surface heater and coolant shell separated by foam insulation. It is lightweight and requires relatively little power.

  8. Chamber Music: Skills and Teamwork.

    ERIC Educational Resources Information Center

    Villarrubia, Charles

    2000-01-01

    Focuses on the benefits of participating in chamber music ensembles, such as the development of a heightened level of awareness, and considers the role of the music educator/conductor. Provides tools and exercises that teachers can introduce to chamber music players to improve their rehearsals and performances. (CMK)

  9. Ion chamber based neutron detectors

    DOEpatents

    Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

    2014-12-16

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  10. A large high vacuum, high pumping speed space simulation chamber for electric propulsion

    NASA Technical Reports Server (NTRS)

    Grisnik, Stanley P.; Parkes, James E.

    1994-01-01

    Testing high power electric propulsion devices poses unique requirements on space simulation facilities. Very high pumping speeds are required to maintain high vacuum levels while handling large volumes of exhaust products. These pumping speeds are significantly higher than those available in most existing vacuum facilities. There is also a requirement for relatively large vacuum chamber dimensions to minimize facility wall/thruster plume interactions and to accommodate far field plume diagnostic measurements. A 4.57 m (15 ft) diameter by 19.2 m (63 ft) long vacuum chamber at NASA Lewis Research Center is described. The chamber utilizes oil diffusion pumps in combination with cryopanels to achieve high vacuum pumping speeds at high vacuum levels. The facility is computer controlled for all phases of operation from start-up, through testing, to shutdown. The computer control system increases the utilization of the facility and reduces the manpower requirements needed for facility operations.

  11. BOREAS TGB-1/TGB-3 CH4 Chamber Flux Data over the NSA Fen

    NASA Technical Reports Server (NTRS)

    Bubier, Jill L.; Moore, Tim R.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-3 team collected methane (CH4) chamber flux measurements at the NSA fen site during May-September 1994 and June-October 1996. Gas samples were extracted approximately every 7 days from chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  12. Starting a High School Chamber Music Group.

    ERIC Educational Resources Information Center

    Rutkowski, Joseph

    2000-01-01

    Presents ideas on how to begin a chamber music ensemble. Discusses how to find time to accomplish chamber music playing in and around the school day. Presents short descriptions of chamber music that can be used with ensembles. Includes chamber music resources and additional chamber works. (CMK)

  13. Neutron detection via bubble chambers.

    PubMed

    Jordan, D V; Ely, J H; Peurrung, A J; Bond, L J; Collar, J I; Flake, M; Knopf, M A; Pitts, W K; Shaver, M; Sonnenschein, A; Smart, J E; Todd, L C

    2005-01-01

    Research investigating the application of pressure-cycled bubble chambers to fast neutron detection is described. Experiments with a Halon-filled chamber showed clear sensitivity to an AmBe neutron source and insensitivity to a (137)Cs gamma source. Bubble formation was documented using high-speed photography, and a ceramic piezo-electric transducer element registered the acoustic signature of bubble formation. In a second set of experiments, the bubble nucleation response of a Freon-134a chamber to an AmBe neutron source was documented with high-speed photography.

  14. IRIS Leaves Thermal Vacuum Chamber

    NASA Video Gallery

    This video shows the transportation of the IRIS observatory from the thermal vacuum chamber back to the clean tent for final testing and preparations for delivery to the launch site at Vandenberg A...

  15. The multigap resistive plate chamber

    SciTech Connect

    Zeballos, E. Cerron; Crotty, I.; Hatzifotiadou, D.; Valverde, J. Lamas; Neupane, S.; Williams, M. C. S.; Zichichi, A.

    2015-02-03

    The paper describes the multigap resistive plate chamber (RPC). This is a variant of the wide gap RPC. However it has much improved time resolution, while keeping all the other advantages of the wide gap RPC design.

  16. Light diffusing fiber optic chamber

    DOEpatents

    Maitland, Duncan J.

    2002-01-01

    A light diffusion system for transmitting light to a target area. The light is transmitted in a direction from a proximal end to a distal end by an optical fiber. A diffusing chamber is operatively connected to the optical fiber for transmitting the light from the proximal end to the distal end and transmitting said light to said target area. A plug is operatively connected to the diffusing chamber for increasing the light that is transmitted to the target area.

  17. Analysis of physical processes in ICF target chambers

    SciTech Connect

    MacFarlane, J.J.; Peterson, R.R.; Moses, G.A.

    1989-03-01

    When a high-gain inertial fusion target explodes, roughly one third of the energy is released in the form of x-rays and energetic ions, which can damage the wall of the chamber. One method of protecting the wall is to place a gas in the chamber cavity. The authors use a 1-D Lagrangian radiation-hydrodynamics code (CONRAD) to study the target energy deposition in this cavity gas and first surface material, the growth of and radiative emission from the microfireball, the expansion of the shock front, the vaporization and hydromotion of the first surface material, and the recondensation of that material back onto the wall. The authors describe recent improvements to CONRAD, and present results for two target chamber designs currently being considered by Lawrence Livermore National Laboratory for the Laboratory Microfusion Facility.

  18. Spectra, composition, and interactions of nuclei with magnet interaction chambers

    NASA Technical Reports Server (NTRS)

    Parneil, T. A.; Derrickson, J. H.; Fountain, W. F.; Roberts, F. E.; Tabuki, T.; Watts, J. W.; Burnett, T. H.; Cherry, M. C.; Dake, S.; Fuki, M.

    1990-01-01

    Emulsion chambers will be flown in the Astromag Facility to measure the cosmic ray composition and spectra to 10 exp 15 eV total energy and to definitively study the characteristics of nucleus-nucleus interactions above 10 exp 12 eV/n. Two configurations of emulsion chambers will be flown in the SCIN/MAGIC experiment. One chamber has an emulsion target and a calorimeter similar to those recently flown on balloons for composition and spectra measurements. The other has an identical calorimeter and a low-density target section optimized for performing rigidity measurements on charged particles produced in interactions. The transverse momenta of charged and neutral mesons, direct hadronic pairs from resonance decays and interference effects, and possible charge clustering in high-density states of matter will be studied.

  19. 63. Interior view, kitchen chamber, north elevation. The kitchen chamber ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    63. Interior view, kitchen chamber, north elevation. The kitchen chamber was completed in the first stages of phase III construction. The paneled wall to the fireplace's right displays a phase III molding profile. The mark between the cabinet doors and on the large lower panel indicates the former position of a partition wall. The chimney-breast paneling bears a phase I profile and might have been moved to the room when the fireplace mass in the hall was reduced. - John Bartram House & Garden, House, 54th Street & Lindbergh Boulevard, Philadelphia, Philadelphia County, PA

  20. Microgravity Simulation Facility (MSF)

    NASA Technical Reports Server (NTRS)

    Richards, Stephanie E. (Compiler); Levine, Howard G.; Zhang, Ye

    2016-01-01

    The Microgravity Simulator Facility (MSF) at Kennedy Space Center (KSC) was established to support visiting scientists for short duration studies utilizing a variety of microgravity simulator devices that negate the directional influence of the "g" vector (providing simulated conditions of micro or partial gravity). KSC gravity simulators can be accommodated within controlled environment chambers allowing investigators to customize and monitor environmental conditions such as temperature, humidity, CO2, and light exposure.

  1. Plant growth chamber M design

    NASA Technical Reports Server (NTRS)

    Prince, R. P.; Knott, W. M.

    1986-01-01

    Crop production is just one of the many processes involved in establishing long term survival of man in space. The benefits of integrating higher plants into the overall plan was recognized early by NASA through the Closed Ecological Life Support System (CELSS) program. The first step is to design, construct, and operate a sealed (gas, liquid, and solid) plant growth chamber. A 3.6 m diameter by 6.7 m high closed cylinder (previously used as a hypobaric vessel during the Mercury program) is being modified for this purpose. The chamber is mounted on legs with the central axis vertical. Entrance to the chamber is through an airlock. This chamber will be devoted entirely to higher plant experimentation. Any waste treatment, food processing or product storage studies will be carried on outside of this chamber. Its primary purpose is to provide input and output data on solids, liquids, and gases for single crop species and multiple species production using different nutrient delivery systems.

  2. Emulsion Chamber Technology Experiment (ECT)

    NASA Technical Reports Server (NTRS)

    Gregory, John C.; Takahashi, Yoshiyuki

    1996-01-01

    The experimental objective of Emulsion Chamber Technology (ECT) was to develop space-borne emulsion chamber technology so that cosmic rays and nuclear interactions may subsequently be studied at extremely high energies with long exposures in space. A small emulsion chamber was built and flown on flight STS-62 of the Columbia in March 1994. Analysis of the several hundred layers of radiation-sensitive material has shown excellent post-flight condition and suitability for cosmic ray physics analysis at much longer exposures. Temperature control of the stack was 20 +/-1 C throughout the active control period and no significant deviations of temperature or pressure in the chamber were observed over the entire mission operations period. The unfortunate flight attitude of the orbiter (almost 90% Earth viewing) prevented any significant number of heavy particles (Z greater than or equal to 10) reaching the stack and the inverted flow of shower particles in the calorimeter has not allowed evaluation of absolute primary cosmic ray-detection efficiency nor of the practical time limits of useful exposure of these calorimeters in space to the level of detail originally planned. Nevertheless, analysis of the observed backgrounds and quality of the processed photographic and plastic materials after the flight show that productive exposures of emulsion chambers are feasible in low orbit for periods of up to one year or longer. The engineering approaches taken in the ECT program were proven effective and no major environmental obstacles to prolonged flight are evident.

  3. Neutron Detection via Bubble Chambers

    SciTech Connect

    Jordan, David V.; Ely, James H.; Peurrung, Anthony J.; Bond, Leonard J.; Collar, J. I.; Flake, Matthew; Knopf, Michael A.; Pitts, W. K.; Shaver, Mark W.; Sonnenschein, Andrew; Smart, John E.; Todd, Lindsay C.

    2005-10-06

    The results of a Pacific Northwest National Laboratory (PNNL) exploratory research project investigating the feasibility of fast neutron detection using a suitably prepared and operated, pressure-cycled bubble chamber are described. The research was conducted along two parallel paths. Experiments with a slow pressure-release Halon chamber at the Enrico Fermi Institute at the University of Chicago showed clear bubble nucleation sensitivity to an AmBe neutron source and insensitivity to the 662 keV gammas from a 137Cs source. Bubble formation was documented via high-speed (1000 frames/sec) photography, and the acoustic signature of bubble formation was detected using a piezo-electric transducer element mounted on the base of the chamber. The chamber’s neutron sensitivity as a function of working fluid temperature was mapped out. The second research path consisted of the design, fabrication, and testing of a fast pressure-release Freon-134a chamber at PNNL. The project concluded with successful demonstrations of the PNNL chamber’s AmBe neutron source sensitivity and 137Cs gamma insensitivity. The source response tests of the PNNL chamber were documented with high-speed photography.

  4. Plasma chemistry in wire chambers

    SciTech Connect

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an {sup 55}Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed.

  5. Ames Hybrid Combustion Facility

    NASA Technical Reports Server (NTRS)

    Zilliac, Greg; Karabeyoglu, Mustafa A.; Cantwell, Brian; Hunt, Rusty; DeZilwa, Shane; Shoffstall, Mike; Soderman, Paul T.; Bencze, Daniel P. (Technical Monitor)

    2003-01-01

    The report summarizes the design, fabrication, safety features, environmental impact, and operation of the Ames Hybrid-Fuel Combustion Facility (HCF). The facility is used in conducting research into the scalability and combustion processes of advanced paraffin-based hybrid fuels for the purpose of assessing their applicability to practical rocket systems. The facility was designed to deliver gaseous oxygen at rates between 0.5 and 16.0 kg/sec to a combustion chamber operating at pressures ranging from 300 to 900. The required run times were of the order of 10 to 20 sec. The facility proved to be robust and reliable and has been used to generate a database of regression-rate measurements of paraffin at oxygen mass flux levels comparable to those of moderate-sized hybrid rocket motors.

  6. Iridium-Coated Rhenium Combustion Chamber

    NASA Technical Reports Server (NTRS)

    Schneider, Steven J.; Tuffias, Robert H.; Rosenberg, Sanders D.

    1994-01-01

    Iridium-coated rhenium combustion chamber withstands operating temperatures up to 2,200 degrees C. Chamber designed to replace older silicide-coated combustion chamber in small rocket engine. Modified versions of newer chamber could be designed for use on Earth in gas turbines, ramjets, and scramjets.

  7. The CLAS drift chamber system

    SciTech Connect

    Mestayer, M.D.; Carman, D.S.; Asavaphibhop, B.

    1999-04-01

    Experimental Hall B at Jefferson Laboratory houses the CEBAF Large Acceptance Spectrometer, the magnetic field of which is produced by a superconducting toroid. The six coils of this toroid divide the detector azimuthally into six sectors, each of which contains three large multi-layer drift chambers for tracking charged particles produced from a fixed target on a toroidal axis. Within the 18 drift chambers are a total of 35,148 individually instrumented hexagonal drift cells. The novel geometry of these chambers provides for good tracking resolution and efficiency, along with large acceptance. The design and construction challenges posed by these large-scale detectors are described, and detailed results are presented from in-beam measurements.

  8. Impedances of Laminated Vacuum Chambers

    SciTech Connect

    Burov, A.; Lebedev, V.; /Fermilab

    2011-06-22

    First publications on impedance of laminated vacuum chambers are related to early 70s: those are of S. C. Snowdon [1] and of A. G. Ruggiero [2]; fifteen years later, a revision paper of R. Gluckstern appeared [3]. All the publications were presented as Fermilab preprints, and there is no surprise in that: the Fermilab Booster has its laminated magnets open to the beam. Being in a reasonable mutual agreement, these publications were all devoted to the longitudinal impedance of round vacuum chambers. The transverse impedance and the flat geometry case were addressed in more recent paper of K. Y. Ng [4]. The latest calculations of A. Macridin et al. [5] revealed some disagreement with Ref. [4]; this fact stimulated us to get our own results on that matter. Longitudinal and transverse impendances are derived for round and flat laminated vacuum chambers. Results of this paper agree with Ref. [5].

  9. Hydrostatic Hyperbaric Chamber Ventilation System

    NASA Technical Reports Server (NTRS)

    Sargusingh, Miriam M.

    2011-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications, including the treatment of medical conditions. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy available in the developing world for the treatment of a variety of medical conditions. Specifically, hyperbaric oxygen therapy is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. Hyperbaric oxygen therapy is simply too expensive and too dangerous to implement in the developing world using standard equipment. The hydrostatic hyperbaric chamber technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system that will provide controlled pressurization of the system, and provide adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the

  10. Open-chamber combustion study

    NASA Astrophysics Data System (ADS)

    Meyers, D. P.; Meyer, R. C.

    1994-04-01

    The test program was undertaken to research trade-offs between engine design and operational parameters on open-chamber, premixed spark-ignited gas engines, with a primary focus on combustion effects. This included combustion chamber designs which are conceptually diametrically opposed -- a high squish design typical of diesel engines and a virtually quiescent design. The reader should note that these data are somewhat abstract compared to conventional engines, because the Labeco test engine has exceptionally high friction and the lean-burn data were run unboosted.

  11. The Mark III vertex chamber

    SciTech Connect

    Adler, J.; Bolton, T.; Bunnell, K.; Cassell, R.; Cheu, E.; Freese, T.; Grab, C.; Mazaheri, G.; Mir, R.; Odian, A.

    1987-07-01

    The design and construction of the new Mark III vertex chamber is described. Initial tests with cosmic rays prove the ability of track reconstruction and yield triplet resolutions below 50 ..mu..m at 3 atm using argon/ethane (50:50). Also performed are studies using a prototype of a pressurized wire vertex chamber with 8 mm diameter straw geometry. Spatial resolution of 35mm was obtained using dimethyl ether (DME) at 1 atm and 30 ..mu..m using argon/ethane (50/50 mixture) at 4 atm. Preliminary studies indicate the DME to adversely affect such materials as aluminized Mylar and Delrin.

  12. Test chamber for alpha spectrometry

    DOEpatents

    Larsen, Robert P.

    1977-01-01

    Alpha emitters for low-level radiochemical analysis by measurement of alpha spectra are positioned precisely with respect to the location of a surface-barrier detector by means of a chamber having a removable threaded planchet holder. A pedestal on the planchet holder holds a specimen in fixed engagement close to the detector. Insertion of the planchet holder establishes an O-ring seal that permits the chamber to be pumped to a desired vacuum. The detector is protected against accidental contact and resulting damage.

  13. Laboratory Course on Drift Chambers

    NASA Astrophysics Data System (ADS)

    García-Ferreira, Ix-B.; García-Herrera, J.; Villaseñor, L.

    2006-09-01

    Drift chambers play an important role in particle physics experiments as tracking detectors. We started this laboratory course with a brief review of the theoretical background and then moved on to the the experimental setup which consisted of a single-sided, single-cell drift chamber. We also used a plastic scintillator paddle, standard P-10 gas mixture (90% Ar, 10% CH4) and a collimated 90Sr source. During the laboratory session the students performend measurements of the following quantities: a) drift velocities and their variations as function of the drift field; b) gas gains and c) diffusion of electrons as they drifted in the gas.

  14. Characterization and testing of a new environmental chamber

    NASA Astrophysics Data System (ADS)

    Leskinen, A.; Yli-Pirilä, P.; Kuuspalo, K.; Sippula, O.; Jalava, P.; Hirvonen, M.-R.; Jokiniemi, J.; Virtanen, A.; Komppula, M.; Lehtinen, K. E. J.

    2015-06-01

    A 29 m3 Teflon chamber, designed for studies on the aging of combustion aerosols, at the University of Eastern Finland is described and characterized. The chamber is part of a research facility, called Ilmari, where small-scale combustion devices, a dynamometer for vehicle exhaust studies, dilution systems, the chamber, and cell and animal exposure devices are located side by side under the same roof. The small surface-to-volume ratio of the chamber enables reasonably long experiment times, with particle wall loss rate constants of 0.088, 0.080, 0.045, and 0.040 h-1 for polydisperse, 50, 100, and 200 nm monodisperse aerosols, respectively. The NO2 photolysis rate can be adjusted from 0 to 0.62 min-1. The irradiance spectrum is centered at either 350 or 365 nm, and the maximum irradiance, produced by up to 160 blacklight lamps, is 29.7 W m-2, which corresponds to the ultraviolet (UV) irradiance in Central Finland at noon on a sunny day in the midsummer. The temperature inside the chamber is uniform and can be kept at 25±1 °C. The chamber is kept in an overpressure with a moving top frame, which reduces sample dilution and entrance of contamination during an experiment. The functionality of the chamber was tested with oxidation experiments of toluene, resulting in secondary organic aerosol (SOA) yields of 12-42%, depending on the initial conditions, such as NOx concentration and UV irradiation. The highest gaseous oxidation product yields of 12.4-19.5% and 5.8-19.5% were detected with ions corresponding to methyl glyoxal (m/z 73.029) and 4-oxo-2-pentenal (m/z 99.044), respectively. Overall, reasonable yields of SOA and gaseous reaction products, comparable to those obtained in other laboratories, were obtained.

  15. Atmosphere contamination following repainting of a human hyperbaric chamber complex.

    PubMed

    Lillo, R S; Morris, J W; Caldwell, J M; Balk, D M; Flynn, E T

    1990-09-01

    The Naval Medical Research Institute currently conducts hyperbaric research in a Man-Rated Chamber Complex (MRCC) originally installed in 1977. Significant engineering alterations to the MRCC and rusting of some of its interior sections necessitated repainting, which was completed in 1988. Great care was taken in selecting an appropriate paint (polyamide epoxy) and in ensuring correct application and curing procedures. Only very low levels of hydrocarbons were found in the MRCC atmosphere before initial pressurization after painting and curing. After pressurization, however, significant chemical contamination was found. The primary contaminants were aromatic hydrocarbons: xylenes (which were a major component of both the primer and topcoat paint) and ethyl benzene. The role that pressure played in stimulating off-gassing from the paint is not clear; the off-gassing rate was observed to be similar over a large range in chamber pressures from 1.6 to 31.0 atm abs. Scrubbing the chamber atmosphere with the chemical absorbent Purafil was effective in removing the contaminants. Contamination has been observed to slowly decline with chamber use and is expected to continue to improve with time. However, this contamination experience emphasizes the need for a high precision gas analysis program at any diving facility to ensure the safety of the breathing gas and chamber atmosphere.

  16. Annular-Cross-Section CFE Chamber

    NASA Technical Reports Server (NTRS)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Proposed continuous-flow-electrophoresis (CFE) chamber of annular cross section offers advantages over conventional CFE chamber, and wedge-cross-section chamber described in "Increasing Sensitivity in Continuous-Flow Electrophoresis" (MFS-26176). In comparison with wedge-shaped chamber, chamber of annular cross section virtually eliminates such wall effects as electro-osmosis and transverse gradients of velocity. Sensitivity enhanced by incorporating gradient maker and radial (collateral) flow.

  17. Evaluation of Impinging Stream Vortex Chamber Concepts for Liquid Rocket Engine Applications

    NASA Technical Reports Server (NTRS)

    Trinh, Huu P.; Bullard, Brad; Kopicz, Charles; Michaels, Scott

    2002-01-01

    for the liquid oxygen (LOX) hydrocarbon fuel (RP-1) system has been derived from the one for the gel propellant. An unlike impinging injector was employed to deliver the propellants to the chamber. MSFC is also conducting an alternative injection scheme, called the chasing injector, associated with this vortex chamber concept. In this injection technique, both propellant jets and their impingement point are in the same chamber cross-sectional plane. Long duration tests (approximately up to 15 seconds) will be conducted on the ISVC to study the thermal effects. This paper will report the progress of the subject efforts at NASA Marshall Space Flight Center. Thrust chamber performance and thermal wall compatibility will be evaluated. The chamber pressures, wall temperatures, and thrust will be measured as appropriate. The test data will be used to validate CFD models, which, in turn, will be used to design the optimum vortex chambers. Measurements in the previous tests showed that the chamber pressures vary significantly with radius. This is due to the existence of the vortices in the chamber flow field. Hence, the combustion efficiency may not be easily determined from chamber pressure. For this project, measured thrust data will be collected. The performance comparison will be in terms of specific impulse efficiencies. In addition to the thrust measurements, several pressure and temperature readings at various locations on the chamber head faceplate and the chamber wall will be made. The first injector and chamber were designed and fabricated based on the available data and experience gained during gel propellant system tests by the U.S. Army. The alternate injector for the ISVC was also fabricated. Hot-fire tests of the vortex chamber are about to start and are expected to complete in February of 2003 at the TS115 facility of MSFC.

  18. Lightweight Chambers for Thrust Assemblies

    NASA Technical Reports Server (NTRS)

    Elam, Sandra K.; Lee, Jonathan; Holmes, Richard; Zimmerman, Frank; Effinger, Mike; Turner, James E. (Technical Monitor)

    2001-01-01

    The Marshall Space Flight Center (MSFC) of the National Aeronautics and Space Administration (NASA) has successfully applied new materials and fabrication techniques to create actively cooled thrust chambers that operate 200-400 degrees hotter and weigh 50% lighter than conventional designs. In some vehicles, thrust assemblies account for as much as 20% of the engine weight. So, reducing the weight of these components and increasing their operating range will benefit many engines and vehicle designs, including Reusable Launch Vehicle (RLV) concepts. Obviously, copper and steel alloys have been used successfully for many years in the chamber components of thrust assemblies. Yet, by replacing the steel alloys with Polymer Matrix Composite (PMC) and/or Metal Matrix Composite (MMC) materials, design weights can be drastically reduced. In addition, replacing the traditional copper alloys with a Ceramic Matrix Composite (CMC) or an advanced copper alloy (Cu-8Cr-4Nb, also known as GRCop-84) significantly increases allowable operating temperatures. Several small MMC and PMC demonstration chambers have recently been fabricated with promising results. Each of these designs included GRCop-84 for the cooled chamber liner. These units successfully verified that designs over 50% lighter are feasible. New fabrication processes, including advanced casting technology and a low cost vacuum plasma spray (VPS) process, were also demonstrated with these units. Hot-fire testing at MSFC is currently being conducted on the chambers to verify increased operating temperatures available with the GRCop-84 liner. Unique CMC chamber liners were also successfully fabricated and prepared for hot-fire testing. Yet, early results indicate these CMC liners need significantly more development in order to use them in required chamber designs. Based on the successful efforts with the MMC and PMC concepts, two full size "lightweight" chambers are currently being designed and fabricated for hot

  19. Thermal System Upgrade of the Space Environment Simulation Test Chamber

    NASA Technical Reports Server (NTRS)

    Desai, Ashok B.

    1997-01-01

    The paper deals with the refurbishing and upgrade of the thermal system for the existing thermal vacuum test facility, the Space Environment Simulator, at NASA's Goddard Space Flight Center. The chamber is the largest such facility at the center. This upgrade is the third phase of the long range upgrade of the chamber that has been underway for last few years. The first phase dealt with its vacuum system, the second phase involved the GHe subsystem. The paper describes the considerations of design philosophy options for the thermal system; approaches taken and methodology applied, in the evaluation of the remaining "life" in the chamber shrouds and related equipment by conducting special tests and studies; feasibility and extent of automation, using computer interfaces and Programmable Logic Controllers in the control system and finally, matching the old components to the new ones into an integrated, highly reliable and cost effective thermal system for the facility. This is a multi-year project just started and the paper deals mainly with the plans and approaches to implement the project successfully within schedule and costs.

  20. Neutron facility for radiobiological studies

    NASA Astrophysics Data System (ADS)

    Policroniades, Rafael; Varela, A.; Guzman, J.; Graaf, U.

    1997-02-01

    A neutron facility suitable for radiobiological applications is described. The small chamber can house, either, solid targets or a gas target. Using this facility, absorbed doses ranging up to 7.2 Gy were delivered to Drosophila melanogaster larvae in order to study induced somatic mutation and mitiotic recombination. Some preliminary results concerning these effects, related to a mean neutron energy of 2.15 MeV provided by a d + Be source, are presented.

  1. Simulation of Layered Magma Chambers.

    ERIC Educational Resources Information Center

    Cawthorn, Richard Grant

    1991-01-01

    The principles of magma addition and liquid layering in magma chambers can be demonstrated by dissolving colored crystals. The concepts of density stratification and apparent lack of mixing of miscible liquids is convincingly illustrated with hydrous solutions at room temperature. The behavior of interstitial liquids in "cumulus" piles can be…

  2. Nondestructive test of regenerative chambers

    NASA Technical Reports Server (NTRS)

    Malone, G. A.; Stauffis, R.; Wood, R.

    1972-01-01

    Flat panels simulating internally cooled regenerative thrust chamber walls were fabricated by electroforming, brazing and diffusion bonding to evaluate the feasibility of nondestructive evaluation techniques to detect bonds of various strength integrities. Ultrasonics, holography, and acoustic emission were investigated and found to yield useful and informative data regarding the presence of bond defects in these structures.

  3. Chamber Music for Every Instrumentalist.

    ERIC Educational Resources Information Center

    Latten, James E.

    2001-01-01

    Discusses why students who play musical instruments should participate in a chamber music ensemble. Provides rationale for using small ensembles in the high school band curriculum. Focuses on the topic of scheduling, illustrating how to insert small ensembles into the lesson schedule, and how to set up a new schedule. (CMK)

  4. Chamber Music for Better Bands.

    ERIC Educational Resources Information Center

    Brown, Michael R.

    1998-01-01

    Considers why students should participate in a chamber music ensemble: (1) students develop a sense of collegiality and self-worth; (2) ensembles encourage practice time; and (3) ensembles provide flexible performance opportunities. Highlights the different aspects of creating an ensemble from the availability of faculty to selecting challenging…

  5. Chamber Clearing First Principles Modeling

    SciTech Connect

    Loosmore, G

    2009-06-09

    LIFE fusion is designed to generate 37.5 MJ of energy per shot, at 13.3 Hz, for a total average fusion power of 500 MW. The energy from each shot is partitioned among neutrons ({approx}78%), x-rays ({approx}12%), and ions ({approx}10%). First wall heating is dominated by x-rays and debris because the neutron mean free path is much longer than the wall thickness. Ion implantation in the first wall also causes damage such as blistering if not prevented. To moderate the peak-pulse heating, the LIFE fusion chamber is filled with a gas (such as xenon) to reduce the peak-pulse heat load. The debris ions and majority of the x-rays stop in the gas, which re-radiates this energy over a longer timescale (allowing time for heat conduction to cool the first wall sufficiently to avoid damage). After a shot, because of the x-ray and ion deposition, the chamber fill gas is hot and turbulent and contains debris ions. The debris needs to be removed. The ions increase the gas density, may cluster or form aerosols, and can interfere with the propagation of the laser beams to the target for the next shot. Moreover, the tritium and high-Z hohlraum debris needs to be recovered for reuse. Additionally, the cryogenic target needs to survive transport through the gas mixture to the chamber center. Hence, it will be necessary to clear the chamber of the hot contaminated gas mixture and refill it with a cool, clean gas between shots. The refilling process may create density gradients that could interfere with beam propagation, so the fluid dynamics must be studied carefully. This paper describes an analytic modeling effort to study the clearing and refilling process for the LIFE fusion chamber. The models used here are derived from first principles and balances of mass and energy, with the intent of providing a first estimate of clearing rates, clearing times, fractional removal of ions, equilibrated chamber temperatures, and equilibrated ion concentrations for the chamber. These can be used

  6. Chamber and target technology development for inertial fusion energy

    SciTech Connect

    Abdou, M; Besenbruch, G; Duke, J; Forman, L; Goodin, D; Gulec, K; Hoffer, J; Khater, H; Kulcinsky, G; Latkowski, J F; Logan, B G; Margevicious, B; Meier, W R; Moir, R W; Morley, N; Nobile, A; Payne, S; Peterson, P F; Peterson, R; Petzoldt, R; Schultz, K; Steckle, W; Sviatoslavsky, L; Tillack, M; Ying, A

    1999-04-07

    Fusion chambers and high pulse-rate target systems for inertial fusion energy (IFE) must: regenerate chamber conditions suitable for target injection, laser propagation, and ignition at rates of 5 to 10 Hz; extract fusion energy at temperatures high enough for efficient conversion to electricity; breed tritium and fuel targets with minimum tritium inventory; manufacture targets at low cost; inject those targets with sufficient accuracy for high energy gain; assure adequate lifetime of the chamber and beam interface (final optics); minimize radioactive waste levels and annual volumes; and minimize radiation releases under normal operating and accident conditions. The primary goal of the US IFE program over the next four years (Phase I) is to develop the basis for a Proof-of-Performance-level driver and target chamber called the Integrated Research Experiment (IRE). The IRE will explore beam transport and focusing through prototypical chamber environment and will intercept surrogate targets at high pulse rep-rate. The IRE will not have enough driver energy to ignite targets, and it will be a non-nuclear facility. IRE options are being developed for both heavy ion and laser driven IFE. Fig. 1 shows that Phase I is prerequisite to an IRE, and the IRE plus NIF (Phase II) is prerequisite to a high-pulse rate. Engineering Test Facility and DEMO for IFE, leading to an attractive fusion power plant. This report deals with the Phase-I R&D needs for the chamber, driver/chamber interface (i.e., magnets for accelerators and optics for lasers), target fabrication, and target injection; it is meant to be part of a more comprehensive IFE development plan which will include driver technology and target design R&D. Because of limited R&D funds, especially in Phase I, it is not possible to address the critical issues for all possible chamber and target technology options for heavy ion or laser fusion. On the other hand, there is risk in addressing only one approach to each technology

  7. Hydrostatic Hyperbaric Chamber Ventilation System

    NASA Technical Reports Server (NTRS)

    Sarguisingh, Miriam J.

    2012-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy (HBOT) available in the developing world for the treatment of a variety of medical conditions. Specifically, HBOT is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. HBOT is simply too expensive and too dangerous to implement in the developing world using standard equipment. The HHC technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system to provide controlled pressurization and adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware

  8. Chamber dynamic research with pulsed power

    SciTech Connect

    PETERSON,ROBERT R.; OLSON,CRAIG L.; RENK,TIMOTHY J.; ROCHAU,GARY E.; SWEENEY,MARY ANN

    2000-05-15

    In Inertial Fusion Energy (IFE), Target Chamber Dynamics (TCD) is an integral part of the target chamber design and performance. TCD includes target output deposition of target x-rays, ions and neutrons in target chamber gases and structures, vaporization and melting of target chamber materials, radiation-hydrodynamics in target chamber vapors and gases, and chamber conditions at the time of target and beam injections. Pulsed power provides a unique environment for IFE-TCD validation experiments in two important ways: they do not require the very clean conditions which lasers need and they currently provide large x-ray and ion energies.

  9. MSFC ESL Facility and Beamline Studies

    NASA Technical Reports Server (NTRS)

    Rogers, J. R.; Hyers, R. W.; Rathz, T. J.; Robinson, M. B.; Kelton, K. F.; Gangopadhyay, A. K.; Woo, G. L.; Fountain, G.; Huie, D.; Allen, T.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    The poster presentation provides an overview of the MSFC ESL facility. The technical capabilities and accomplishments of the facility are summarized. Future plans including the development of a pressurized processing chamber and additional high-energy X-ray beamline studies are outlined.

  10. Recent Enhancements to the NASA Langley Structural Acoustics Loads and Transmission (SALT) Facility

    NASA Technical Reports Server (NTRS)

    Rizzi, Stephen A.; Cabell, Randolph H.; Allen, Albert R.

    2013-01-01

    The Structural Acoustics Loads and Transmission (SALT) facility at the NASA Langley Research Center is comprised of an anechoic room and a reverberant room, and may act as a transmission loss suite when test articles are mounted in a window connecting the two rooms. In the latter configuration, the reverberant room acts as the noise source side and the anechoic room as the receiver side. The noise generation system used for qualification testing in the reverberant room was previously shown to achieve a maximum overall sound pressure level of 141 dB. This is considered to be marginally adequate for generating sound pressure levels typically required for launch vehicle payload qualification testing. Recent enhancements to the noise generation system increased the maximum overall sound pressure level to 154 dB, through the use of two airstream modulators coupled to 35 Hz and 160 Hz horns. This paper documents the acoustic performance of the enhanced noise generation system for a variety of relevant test spectra. Additionally, it demonstrates the capability of the SALT facility to conduct transmission loss and absorption testing in accordance with ASTM and ISO standards, respectively. A few examples of test capabilities are shown and include transmission loss testing of simple unstiffened and built up structures and measurement of the diffuse field absorption coefficient of a fibrous acoustic blanket.

  11. Medical devices and procedures in the hyperbaric chamber.

    PubMed

    Kot, Jacek

    2014-12-01

    The aim of this paper is to present current controversies concerning the safety of medical devices and procedures under pressure in a hyperbaric chamber including: defibrillation in a multiplace chamber; implantable devices during hyperbaric oxygen treatment (HBOT) and the results of a recent European questionnaire on medical devices used inside hyperbaric chambers. Early electrical defibrillation is the only effective therapy for cardiac arrest caused by ventricular fibrillation or pulseless ventricular tachycardia. The procedure of defibrillation under hyperbaric conditions is inherently dangerous owing to the risk of fire, but it can be conducted safely if certain precautions are taken. Recently, new defibrillators have been introduced for hyperbaric medicine, which makes the procedure easier technically, but it must be noted that sparks and fire have been observed during defibrillation, even under normobaric conditions. Therefore, delivery of defibrillation shock in a hyperbaric environment must still be perceived as a hazardous procedure. Implantable devices are being seen with increasing frequency in patients referred for HBOT. These devices create a risk of malfunction when exposed to hyperbaric conditions. Some manufacturers support patients and medical practitioners with information on how their devices behave under increased pressure, but in some cases an individual risk-benefit analysis should be conducted on the patient and the specific implanted device, taking into consideration the patient's clinical condition, the indication for HBOT and the capability of the HBOT facility for monitoring and intervention in the chamber. The results of the recent survey on use of medical devices inside European hyperbaric chambers are also presented. A wide range of non-CE-certified equipment is used in European chambers. PMID:25596835

  12. Medical devices and procedures in the hyperbaric chamber.

    PubMed

    Kot, Jacek

    2014-12-01

    The aim of this paper is to present current controversies concerning the safety of medical devices and procedures under pressure in a hyperbaric chamber including: defibrillation in a multiplace chamber; implantable devices during hyperbaric oxygen treatment (HBOT) and the results of a recent European questionnaire on medical devices used inside hyperbaric chambers. Early electrical defibrillation is the only effective therapy for cardiac arrest caused by ventricular fibrillation or pulseless ventricular tachycardia. The procedure of defibrillation under hyperbaric conditions is inherently dangerous owing to the risk of fire, but it can be conducted safely if certain precautions are taken. Recently, new defibrillators have been introduced for hyperbaric medicine, which makes the procedure easier technically, but it must be noted that sparks and fire have been observed during defibrillation, even under normobaric conditions. Therefore, delivery of defibrillation shock in a hyperbaric environment must still be perceived as a hazardous procedure. Implantable devices are being seen with increasing frequency in patients referred for HBOT. These devices create a risk of malfunction when exposed to hyperbaric conditions. Some manufacturers support patients and medical practitioners with information on how their devices behave under increased pressure, but in some cases an individual risk-benefit analysis should be conducted on the patient and the specific implanted device, taking into consideration the patient's clinical condition, the indication for HBOT and the capability of the HBOT facility for monitoring and intervention in the chamber. The results of the recent survey on use of medical devices inside European hyperbaric chambers are also presented. A wide range of non-CE-certified equipment is used in European chambers.

  13. Rocket Engine Thrust Chamber Assembly

    NASA Technical Reports Server (NTRS)

    Cornelius, Charles S. (Inventor); Counts, Richard H. (Inventor); Myers, W. Neill (Inventor); Lackey, Jeffrey D. (Inventor); Peters, Warren (Inventor); Shadoan, Michael D. (Inventor); Sparks, David L. (Inventor); Lawrence, Timothy W. (Inventor)

    2001-01-01

    A thrust chamber assembly for liquid fueled rocket engines and the method of making it wherein a two-piece mandrel wrapped with a silica tape saturated with a phenolic resin, the tape extending along the mandrel and covering the combustion chamber portion of the mandrel to the throat portion. The phenolic in the tape is cured and the end of the wrap is machined. The remainder of the mandrel is wrapped with a third silica tape. The resin in the third tape is cured and the assembly is machined. The entire assembly is then wrapped with a tow of graphite fibers wetted with an epoxy resin and, after the epoxy resin is cured, the graphite is machined to final dimensions.

  14. Space Chambers for Crop Treatment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Vacuum chambers, operated by McDonnell Douglas Corporation to test spacecraft, can also be used to dry water-soaked records. The drying temperature is low enough to allow paper to dry without curling or charging. Agricultural crops may also be dried using a spinoff system called MIVAC, which has proven effective in drying rice, wheat, soybeans, corn, etc. The system is energy efficient and can incorporate a sanitation process for destroying insects without contamination.

  15. The STAR Time Projection Chamber

    SciTech Connect

    Retiere, F.; STAR Collaboration

    2002-01-11

    The STAR Time Projection Chamber was successfully operated during the first RHIC run in 2000. Most of the STAR contributions reported in these proceedings are based on the analysis of data from the TPC. In this article, we show that the performance achieved by the TPC, in terms of track reconstruction, position resolution, and particle identification are well suited for measuring precise and reliable physics observables.

  16. MPS II drift chamber system

    SciTech Connect

    Platner, E.D.

    1982-01-01

    The MPS II detectors are narrow drift space chambers designed for high position resolution in a magnetic field and in a very high particle flux environment. Central to this implementation was the development of 3 multi-channel custom IC's and one multi-channel hybrid. The system is deadtimeless and requires no corrections on an anode-to-anode basis. Operational experience and relevance to ISABELLE detectors is discussed.

  17. Contamination Control Assessment of the World's Largest Space Environment Simulation Chamber

    NASA Technical Reports Server (NTRS)

    Snyder, Aaron; Henry, Michael W.; Grisnik, Stanley P.; Sinclair, Stephen M.

    2012-01-01

    The Space Power Facility s thermal vacuum test chamber is the largest chamber in the world capable of providing an environment for space simulation. To improve performance and meet stringent requirements of a wide customer base, significant modifications were made to the vacuum chamber. These include major changes to the vacuum system and numerous enhancements to the chamber s unique polar crane, with a goal of providing high cleanliness levels. The significance of these changes and modifications are discussed in this paper. In addition, the composition and arrangement of the pumping system and its impact on molecular back-streaming are discussed in detail. Molecular contamination measurements obtained with a TQCM and witness wafers during two recent integrated system tests of the chamber are presented and discussed. Finally, a concluding remarks section is presented.

  18. The crop growth research chamber

    NASA Technical Reports Server (NTRS)

    Wagenbach, Kimberly

    1993-01-01

    The Crop Growth Research Chamber (CGRC) has been defined by CELSS principle investigators and science advisory panels as a necessary ground-based tool in the development of a regenerative life support system. The focus of CGRC research will be on the biomass production component of the CELSS system. The ground-based Crop Growth Research Chamber is for the study of plant growth and development under stringently controlled environments isolated from the external environment. The chamber has importance in three areas of CELSS activities: (1) crop research; (2) system control and integration, and (3) flight hardware design and experimentation. The laboratory size of the CGRC will be small enough to allow duplication of the unit, the conducting of controlled experiments, and replication of experiments, but large enough to provide information representative of larger plant communities. Experiments will focus on plant growth in a wide variety of environments and the effects of those environments on plant production of food, water, oxygen, toxins, and microbes. To study these effects in a closed system, tight control of the environment is necessary.

  19. Rocket Engine Thrust Chamber Assembly

    NASA Technical Reports Server (NTRS)

    Cornelius, Charles S. (Inventor); Counts, Richard H. (Inventor); Myers, W. Neill (Inventor); Lackey, Jeffrey D. (Inventor); Peters, Warren (Inventor); Shadoan, Michael (Inventor); Sparks, David L. (Inventor); Lawrence, Timothy W. (Inventor)

    2001-01-01

    A thrust chamber assembly for liquid fueled rocket engines and the method of making it wherein a two-piece mandrel having the configuration of an assembly having a combustion chamber portion connected to a nozzle portion through a throat portion is wrapped with a silica tape saturated with a phenolic resin, the tape extending along the mandrel and covering the combustion chamber portion of the mandrel to the throat portion. The width of the tape is positioned at an angle of 30 to 50 deg. to the axis of the mandrel such that one edge of the tape contacts the mandrel while the other edge is spaced from the mandrel. The phenolic in the tape is cured and the end of the wrap is machined to provide a frusto-conical surface extending at an angle of 15 to 30 deg. with respect to the axis of the mandrel for starting a second wrap on the mandrel to cover the throat portion. The remainder of the mandrel is wrapped with a third silica tape having its width positioned at a angle of 5 to 20 deg. from the axis of the mandrel. The resin in the third tape is cured and the assembly is machined to provide a smooth outer surface. The entire assembly is then wrapped with a tow of graphite fibers wetted with an epoxy resin and, after the epoxy resin is cured, the graphite is machined to final dimensions.

  20. 21 CFR 868.5470 - Hyperbaric chamber.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... than atmospheric pressure. This device does not include topical oxygen chambers for extremities (§ 878... hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote...

  1. Sensorineural deafness due to compression chamber noise.

    PubMed

    Hughes, K B

    1976-05-01

    A case of unilateral sensorineural deafness following exposure to compression chamber noise is described. A review of the current literature concerning the otological hazards of compression chambers is made. The possible pathological basis is discussed.

  2. BOREAS TGB-1 NSA CH4 and CO2 Chamber Flux Data

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Crill, Patrick; Varner, Ruth K.

    2000-01-01

    The BOREAS TGB-1 team made methane (CH4) and carbon dioxide (CO2) dark chamber flux measurements at the NSA-OJP, NSA-OBS, NSA-BP, and NSA-YJP sites from 16-May-1994 through 13-Sep-1994. Gas samples were extracted approximately every 7 days from dark chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  3. Gas-Grain Simulation Facility (GGSF)

    NASA Technical Reports Server (NTRS)

    Greenwald, Ken

    1992-01-01

    The goal of the Gas-Grain Simulation Facility project is to provide a microgravity laboratory to facilitate research relevant to exobiology (the study of the origin and evolution of life in the universe). Such a facility will also be useful in other areas of study important to NASA including planetary science, biology, atmospheric science, astrophysics, chemistry, and physics. To achieve this goal, the project will develop and support the GGSF, a modular facility-class payload planned for inclusion on Space Station Freedom. The GGSF will consist of the following: an experiment chamber(s) supported by subsystems that provide chamber environment regulation and monitoring capabilities; sample generation, injection, positioning, and retrieval capabilities; and computer control, data acquisition, and housekeeping capabilities. The facility will also provide analytical tools such as light-scattering measurement systems, aerosol size-spectrum measurement devices, and optical imaging systems.

  4. Design and testing of a model CELSS chamber robot

    NASA Technical Reports Server (NTRS)

    Davis, Mark; Dezego, Shawn; Jones, Kinzy; Kewley, Christopher; Langlais, Mike; Mccarthy, John; Penny, Damon; Bonner, Tom; Funderburke, C. Ashley; Hailey, Ruth

    1994-01-01

    A robot system for use in an enclosed environment was designed and tested. The conceptual design will be used to assist in research performed by the Controlled Ecological Life Support System (CELSS) project. Design specifications include maximum load capacity, operation at specified environmental conditions, low maintenance, and safety. The robot system must not be hazardous to the sealed environment, and be capable of stowing and deploying within a minimum area of the CELSS chamber facility. This design consists of a telescoping robot arm that slides vertically on a shaft positioned in the center of the CELSS chamber. The telescoping robot arm consists of a series of links which can be fully extended to a length equal to the radius of the working envelope of the CELSS chamber. The vertical motion of the robot arm is achieved through the use of a combination ball screw/ball spline actuator system. The robot arm rotates cylindrically about the vertical axis through use of a turntable bearing attached to a central mounting structure fitted to the actuator shaft. The shaft is installed in an overhead rail system allowing the entire structure to be stowed and deployed within the CELSS chamber. The overhead rail system is located above the chamber's upper lamps and extends to the center of the CELSS chamber. The mounting interface of the actuator shaft and rail system allows the entire actuator shaft to be detached and removed from the CELSS chamber. When the actuator shaft is deployed, it is held fixed at the bottom of the chamber by placing a square knob on the bottom of the shaft into a recessed square fitting in the bottom of the chamber floor. A support boot ensures the rigidity of the shaft. Three student teams combined into one group designed a model of the CELSS chamber robot that they could build. They investigated materials, availability, and strength in their design. After the model arm and stand were built, the class performed pre-tests on the entire system

  5. Making a fish tank cloud chamber

    NASA Astrophysics Data System (ADS)

    Green, Frances

    2012-05-01

    The cloud chambers described here are large, made from readily available parts, simple to set up and always work. With no source in the chamber, background radiation can be observed. A large chamber means that a long rod containing a weakly radioactive material can be introduced, increasing the chance of seeing decays. Details of equipment and construction are given.

  6. Uniform-Temperature Walls for Cloud Chambers

    NASA Technical Reports Server (NTRS)

    Fleischman, G.

    1985-01-01

    Flat heat pipes rapidly transfer heat to and from experimental volumes. Heat pipe vapor chamber carries heat to and from thermo electric modules. Critical surface acts as evaporator or condenser in cloud physics experiments. Used as walls of spaceborne atmospheric cloud chambers. On Earth, used as isothermal floors for environmental test chambers.

  7. Making a Fish Tank Cloud Chamber

    ERIC Educational Resources Information Center

    Green, Frances

    2012-01-01

    The cloud chambers described here are large, made from readily available parts, simple to set up and always work. With no source in the chamber, background radiation can be observed. A large chamber means that a long rod containing a weakly radioactive material can be introduced, increasing the chance of seeing decays. Details of equipment and…

  8. Simple Cloud Chambers Using Gel Ice Packs

    ERIC Educational Resources Information Center

    Kamata, Masahiro; Kubota, Miki

    2012-01-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

  9. A Sensitive Cloud Chamber without Radioactive Sources

    ERIC Educational Resources Information Center

    Zeze, Syoji; Itoh, Akio; Oyama, Ayu; Takahashi, Haruka

    2012-01-01

    We present a sensitive diffusion cloud chamber which does not require any radioactive sources. A major difference from commonly used chambers is the use of a heat sink as its bottom plate. The result of a performance test of the chamber is given. (Contains 8 figures.)

  10. EPA GAS PHASE CHEMISTRY CHAMBER STUDIES

    EPA Science Inventory

    Gas-phase smog chamber experiments are being performed at EPA in order to evaluate a number of current chemical mechanisms for inclusion in EPA regulatory and research models. The smog chambers are 9000 L in volume and constructed of 2-mil teflon film. One of the chambers is co...

  11. Fluidized wall for protecting fusion chamber walls

    SciTech Connect

    Maniscalco, J.A.; Meier, W.R.

    1982-08-17

    Apparatus for protecting the inner wall of a fusion chamber from microexplosion debris, x-rays, neutrons, etc. Produced by deuterium-tritium (DT) targets imploded within the fusion chamber. The apparatus utilizes a fluidized wall similar to a waterfall comprising liquid lithium or solid pellets of lithiumceramic, the waterfall forming a blanket to prevent damage of the structural materials of the chamber.

  12. Experimental biomass burning emission assessment by combustion chamber

    NASA Astrophysics Data System (ADS)

    Lusini, Ilaria; Pallozzi, Emanuele; Corona, Piermaria; Ciccioli, Paolo; Calfapietra, Carlo

    2014-05-01

    Biomass burning is a significant source of several atmospheric gases and particles and it represents an important ecological factor in the Mediterranean ecosystem. In this work we describe the performances of a recently developed combustion chamber to show the potential of this facility in estimating the emission from wildland fire showing a case study with leaves, small branches and litter of two representative species of Mediterranean vegetation, Quercus pubescens and Pinus halepensis. The combustion chamber is equipped with a thermocouple, a high resolution balance, an epiradiometer, two different sampling lines to collect organic volatile compounds (VOCs) and particles, a sampling line connected to a Proton Transfer Reaction Mass-Spectrometer (PTR-MS) and a portable analyzer to measure CO and CO2 emission. VOCs emission were both analyzed with GC-MS and monitored on-line with PTR-MS. The preliminary qualitative analysis of emission showed that CO and CO2 are the main gaseous species emitted during the smoldering and flaming phase, respectively. Many aromatics VOCs as benzene and toluene, and many oxygenated VOC as acetaldehyde and methanol were also released. This combustion chamber represents an important tool to determine the emission factor of each plant species within an ecosystem, but also the contribution to the emissions of the different plant tissues and the kinetics of different compound emissions during the various combustion phases. Another important feature of the chamber is the monitoring of the carbon balance during the biomass combustion.

  13. Design and construction of a sample preparation chamber for atomic beam scattering

    NASA Astrophysics Data System (ADS)

    Nielsen, C.

    1992-05-01

    A new type of atomic beam scattering spectrometer was built to advance the usefulness of the atomic beam scattering technique as a surface dynamics probe. The facility was not only built to investigate the typical alkali halide samples such as NaCl, NaF, and LiF, but also to investigate metallic surfaces. Metal samples are more complicated to study, due to their reactive surfaces and the sample preparation process. A surface analysis chamber was constructed as an attachment to the scattering facility to treat samples under ultra high vacuum (UHV) and then transfer these samples into the scattering facility. This surface analysis chamber is referred to as the sample preparation chamber and is the basis for this thesis.

  14. Progress and critical issues for IFE blanket and chamber research

    SciTech Connect

    Abdou, M.; Kulcinski, G.L.; Latkowski, J.F.; Logan, B.G.; Meier, W.R.; Moir, R.W.; Nobile, A.; Peterson, P.F.; Petti, D.; Schultz, K.R.; Tillack, M.S.

    1999-06-23

    Advances in high gain target designs for Inertial Fusion Energy (IFE), and the initiation of construction of large megajoule-class laser facilities in the U.S. (National Ignition Facility) and France (Laser-Megajoule) capable of testing the requirements for inertial fusion ignition and propagating burn, have improved the prospects for IFE. Accordingly, there have recently been modest increases in the US fusion research program related to the feasibility of IFE. These research areas include heavy-ion accelerators, Krypton-Fluoride (KrF) gas lasers, diode-pumped, solid-state (DPSSL) lasers, IFE target designs for higher gains, feasibility of low cost IFE target fabrication and accurate injection, and long-lasting IFE fusion chambers and final optics. Since several studies of conceptual IFE power plant and driver designs were completed in 1992-1996 [1-5], U.S. research in the IFE blanket, chamber, and target technology areas has focused on the critical issues relating to the feasibility of IFE concepts towards the goal of achieving economically-competitive and environmentally-attractive fusion energy. This paper discusses the critical issues in these areas, and the approaches taken to address these issues. The U.S. research in these areas, called IFE Chamber and Target Technologies, is coordinated through the Virtual Laboratory for Technology (VLT) formed by the Department of Energy in December 1998.

  15. Triple ion beam irradiation facility

    SciTech Connect

    Lewis, M.B.; Allen, W.R.; Buhl, R.A.; Packan, N.H.; Cook, S.W.; Mansur, L.K.

    1988-12-01

    A unique ion irradiation facility consisting of three accelerators is described. The accelerators can be operated simultaneously to deliver three ion beams on one target sample. The energy ranges of the ions are 50 to 400 keV, 200 keV to 2.5 MeV, and 1.0 to 5.0 MeV. Three different ions in the appropriate mass range can be simultaneously implanted to the same depth in a target specimen as large as 100 mm/sup 2/ in area. Typical depth ranges are 0.1 to 1.0 ..mu..m. The X-Y profiles of all three ion beams are measured by a system of miniature Faraday cups. The low-voltage accelerator can periodically ramp the ion beam energy during the implantation. Three different types of target chambers are in use at this facility. The triple-beam high-vacuum chamber can hold nine transmission electron microscopy specimens at elevated temperature during a irradiation by the three simultaneous beams. A second high-vacuum chamber on the medium-voltage accelerator beamline houses a low- and high-temperature translator and a two-axis goniometer for ion channeling measurements. The third chamber on the high-energy beamline can be gas-filled for special stressed specimen irradiations. Special applications for the surface modification of materials with this facility are described. Appendixes containing operating procedures are also included. 18 refs., 27 figs., 1 tab.

  16. A molecular beam epitaxy facility for in situ neutron scattering

    SciTech Connect

    Dura, J. A.; LaRock, J.

    2009-07-15

    A molecular beam epitaxy (MBE) facility has been built to enable in situ neutron scattering measurements during growth of epitaxial layers. While retaining the full capabilities of a research MBE chamber, this facility has been optimized for polarized neutron reflectometry measurements. Optimization includes a compact lightweight portable design, a neutron window, controllable magnetic field, deposition across a large 76 mm diameter sample with exceptional flux uniformity, and sample temperatures continuously controllable from 38 to 1375 K. A load lock chamber allows for sample insertion, storage of up to 4 samples, and docking with other facilities. The design and performance of this chamber are described here.

  17. Outdoor chamber study to test multi-day effects. Volume 2. Environmental chamber data tabulations. Final report, August 1982-August 1984

    SciTech Connect

    Carter, W.P.L.; Dodd, M.C.; Long, W.D.; Atkinson, R.

    1984-12-01

    The smog chamber facilities of the University of California, Riverside were used to collect experimental data to assess the effects of multi-day irradiations on photochemical oxidant formation. This volume contains the printouts of all the data that were collected in the study. These data are suitable for use in developing and testing kinetic mechanisms of photochemical smog formation.

  18. Liquid argon Time Projection Chamber

    SciTech Connect

    Doe, P.J.; Mahler, H.J.; Chen, H.H.

    1984-01-01

    The principal features of the liquid argon TPC are outlined and the status of development efforts, particularly at UCI, are discussed. Technical problems associated with liquid TPC's are: the liquid must be maintained at a high level of purity to enable long distance drifting of ionization electrons, and the signal size is small due to the absence of practical charge multiplication as found in gas chambers. These problems have been largely resolved in studies using small (1 to 100 l) detectors, thus allowing a realistic consideration of the physics potential of such devices.

  19. Chamber propagation physics for heavy ion fusion

    SciTech Connect

    Callahan, D.A.

    1995-09-01

    Chamber transport is an important area of study for heavy ion fusion. Final focus and chamber-transport are high leverage areas providing opportunities to significantly decrease the cost of electricity from a heavy ion fusion power plant. Chamber transport in two basic regimes is under consideration. In the low chamber density regime ({approx_lt}0.003 torr), ballistic or nearly-ballistic transport is used. Partial beam neutralization has been studied to offset the effects of beam stripping. In the high chamber density regime ({approx_gt}.1 torr), two transport modes (pinched transport and channel transport) are under investigation. Both involve focusing the beam outside the chamber then transporting it at small radius ({approx} 2 mm). Both high chamber density modes relax the constraints on the beam quality needed from the accelerator which will reduce the driver cost and the cost of electricity.

  20. Hydrocarbon-fuel/combustion-chamber-liner materials compatibility

    NASA Technical Reports Server (NTRS)

    Gage, Mark L.

    1990-01-01

    Results of material compatibility experiments using hydrocarbon fuels in contact with copper-based combustion chamber liner materials are presented. Mil-Spec RP-1, n- dodecane, propane, and methane fuels were tested in contact with OFHC, NASA-Z, and ZrCu coppers. Two distinct test methods were employed. Static tests, in which copper coupons were exposed to fuel for long durations at constant temperature and pressure, provided compatibility data in a precisely controlled environment. Dynamic tests, using the Aerojet Carbothermal Test Facility, provided fuel and copper compatibility data under realistic booster engine service conditions. Tests were conducted using very pure grades of each fuel and fuels to which a contaminant, e.g., ethylene or methyl mercaptan, was added to define the role played by fuel impurities. Conclusions are reached as to degradation mechanisms and effects, methods for the elimination of these mechanisms, selection of copper alloy combustion chamber liners, and hydrocarbon fuel purchase specifications.

  1. Status of the construction of the Gluex Forward Drift Chambers

    NASA Astrophysics Data System (ADS)

    Taylor, Simon

    2013-04-01

    Currently under construction at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia, the full GlueX detector is designed to study gluonic degrees of freedom through the production of ``hybrid'' mesons with exotic quantum numbers. To accomplish this task the detector requires high acceptance and reasonably good resolution for both charged and neutral particles. The core of the detector is housed within the bore of a 2.0 Tesla solenoidal magnet. Charged particles emanating from the target for angles greater than about 20 degrees with respect to the beam line will be tracked with a straw-tube detector (the Central Drift Chamber). Forward-going charged particles will be detected using the Forward Drift Chambers (FDC). I will describe the design and construction of the FDC and present preliminary resolution measurements.

  2. [Taylor and Hill, Incorporated's JSC Cryo Chamber A

    NASA Technical Reports Server (NTRS)

    Morales, Rito

    2008-01-01

    NASA commissioned construction of an environmental simulation test chamber which was completed in 1964 at Johnson Space Center (JSC) in Houston, Texas. The facility, Chamber A, was invaluable for testing spacecraft and satellites before deployment to space. By testing spacecraft in an environment similar to the one they would be functioning in, potential problems could be addressed before launch. A new addition to NASA's observatory inventory is called the James Webb Space Telescope (JWST), after a former Administrator of NASA. The new telescope will have 7 times the mirror area of the Hubble, with a target destination approximately one million miles from earth. Scheduled for launch in 2013, the JWST will allow scientists the ability to see, for the first time, the first galaxies that formed in the early Universe. Pre-launch testing of JWST must be performed in environments that approximate its final target space environment as closely as possible.

  3. A Fast Ionization Chamber for GODDESS

    NASA Astrophysics Data System (ADS)

    Lumb, R. T.; Lipman, A. S.; Baugher, T.; Cizewski, J. A.; Ratkiewicz, A.; Pain, S. D.; Kozub, R. L.

    2014-09-01

    Transfer reactions are among the main methods used in nuclear physics to probe the structure of nuclei. Such information is needed to constrain nuclear models and to understand various nucleosynthesis processes. In many cases, the nuclear level densities are too high to be resolved in transfer reactions via charged particle detection alone. This problem and issues arising from contaminants in radioactive beams can be addressed by using particle- γ coincidence techniques along with heavy recoil identification in inverse kinematics. A device to accomplish these tasks is Gammasphere ORRUBA: Dual Detectors for Experimental Structure Studies (GODDESS), currently being commissioned for the ATLAS facility at ANL. We are currently building a compact, tilted grid ionization chamber for GODDESS to detect and identify beam-like recoils near zero degrees in the lab. The tilt (30 degrees off normal to the beam) helps the ion pairs to be detected quickly, after drifting only a short distance away from the beam axis. This reduces the response time, allowing counting rates of ~500,000/s. The design and current status of the project will be presented. Research supported by the U. S. DOE.

  4. Large coil test facility

    SciTech Connect

    Nelms, L.W.; Thompson, P.B.

    1980-01-01

    Final design of the facility is nearing completion, and 20% of the construction has been accomplished. A large vacuum chamber, houses the test assembly which is coupled to appropriate cryogenic, electrical, instrumentation, diagnostc systems. Adequate assembly/disassembly areas, shop space, test control center, offices, and test support laboratories are located in the same building. Assembly and installation operations are accomplished with an overhead crane. The major subsystems are the vacuum system, the test stand assembly, the cryogenic system, the experimental electric power system, the instrumentation and control system, and the data aquisition system.

  5. Thrust chamber material technology program

    NASA Astrophysics Data System (ADS)

    Andrus, J. S.; Bordeau, R. G.

    1989-03-01

    This report covers work performed at Pratt & Whitney on development of copper-based materials for long-life, reusable, regeneratively cooled rocket engine thrust chambers. The program approached the goal of enhanced cyclic life through the application of rapid solidification to alloy development, to introduce fine dispersions to strengthen and stabilize the alloys at elevated temperatures. After screening of alloy systems, copper-based alloys containing Cr, Co, Hf, Ag, Ti, and Zr were processed by rapid-solidification atomization in bulk quantities. Those bulk alloys showing the most promise were characterized by tensile testing, thermal conductivity testing, and elevated-temperature, low-cycle fatigue (LFC) testing. Characterization indicated that Cu- 1.1 percent Hf exhibited the greatest potential as an improved-life thrust chamber material, exhibiting LCF life about four times that of NASA-Z. Other alloys (Cu- 0.6 percent Zr, and Cu- 0.6 percent Zr- 1.0 percent Cr) exhibited promise for use in this application, but needed more development work to balance properties.

  6. Thrust chamber material technology program

    NASA Technical Reports Server (NTRS)

    Andrus, J. S.; Bordeau, R. G.

    1989-01-01

    This report covers work performed at Pratt & Whitney on development of copper-based materials for long-life, reusable, regeneratively cooled rocket engine thrust chambers. The program approached the goal of enhanced cyclic life through the application of rapid solidification to alloy development, to introduce fine dispersions to strengthen and stabilize the alloys at elevated temperatures. After screening of alloy systems, copper-based alloys containing Cr, Co, Hf, Ag, Ti, and Zr were processed by rapid-solidification atomization in bulk quantities. Those bulk alloys showing the most promise were characterized by tensile testing, thermal conductivity testing, and elevated-temperature, low-cycle fatigue (LFC) testing. Characterization indicated that Cu- 1.1 percent Hf exhibited the greatest potential as an improved-life thrust chamber material, exhibiting LCF life about four times that of NASA-Z. Other alloys (Cu- 0.6 percent Zr, and Cu- 0.6 percent Zr- 1.0 percent Cr) exhibited promise for use in this application, but needed more development work to balance properties.

  7. Optical testing cryogenic thermal vacuum facility

    NASA Technical Reports Server (NTRS)

    Dohogne, Patrick W.; Carpenter, Warren A.

    1990-01-01

    The construction of a turnkey cryogenic vacuum test facility was recently completed. The facility will be used to measure and record the surface profile of large diameter and 540 kg optics under simulated space conditions. The vacuum test chamber is a vertical stainless steel cylinder with a 3.5 diameter and a 7 m tangent length. The chamber was designed to maximize optical testing quality by minimizing the vibrations between the laser interferometer and the test specimen. This was accomplished by designing the chamber for a high natural frequency and vibration isolating the chamber. An optical test specimen is mounted on a movable presentation stage. During thermal vacuum testing, the specimen may be positioned to + or - 0.00025 cm accuracy with a fine adjustment mechanism. The chamber is evacuated by a close coupled Roots-type blower and rotary vane pump package and two cryopumps. The chamber is equipped with an optically dense gaseous nitrogen cooled thermal shroud. The thermal shroud is used to cool or warm the optical test specimen at a controlled rate. A control system is provided to automatically evacuate the chamber and cooldown the test specimen to the selected control temperature.

  8. Acoustic facilities for human factors research at NASA Langley Research Center: Description and operational capabilities

    NASA Technical Reports Server (NTRS)

    Hubbard, H. H.; Powell, C. A.

    1981-01-01

    A number of facilities were developed which provide a unique test capability for psychoacoustics and related human factors research. The design philosophy, physical layouts, dimensions, construction features, operating capabilities, and example applications for these facilities are described. In the exterior effects room, human subjects are exposed to the types of noises that are experienced outdoors, and in the interior effects room, subjects are exposed to the types of noises and noise-induced vibrations that are experience indoors. Subjects are also exposed to noises in an echo-free environment in the anechoic listening room. An aircraft noise synthesis system, which simulates aircraft flyover noise at an observer position on the ground, is used in conjunction with these three rooms. The passenger ride quality apparatus, a device for studying passenger response to noise and vibration in aircraft, or in other vehicles, is described.

  9. Neutron-chamber detectors and applications

    SciTech Connect

    Fehlau, P.E.; Atwater, H.F.; Coop, K.L.

    1990-01-01

    Detector applications in Nuclear Safeguards and Waste Management have included measuring neutrons from fission and (alpha,n) reactions with well-moderated neutron proportional counters, often embedded in a slab of polyethylene. Other less-moderated geometries are useful for detecting both bare and moderated fission-source neutrons with good efficiency. The neutron chamber is an undermoderated detector design comprising a large, hollow, polyethylene-walled chamber containing one or more proportional counters. Neutron-chamber detectors are relatively inexpensive; can have large apertures, usually through a thin chamber wall; and offer very good detection efficiency per dollar. Neutron-chamber detectors have also been used for monitoring vehicles and for assaying large crates of transuranic waste. Our Monte Carlo calculations for a new application (monitoring low-density waste for concealed plutonium) illustrate the advantages of the hollow-chamber design for detecting moderated fission sources. 9 refs., 6 figs., 2 tabs.

  10. Sequential Notch activation regulates ventricular chamber development

    PubMed Central

    D'Amato, Gaetano; Luxán, Guillermo; del Monte-Nieto, Gonzalo; Martínez-Poveda, Beatriz; Torroja, Carlos; Walter, Wencke; Bochter, Matthew S.; Benedito, Rui; Cole, Susan; Martinez, Fernando; Hadjantonakis, Anna-Katerina; Uemura, Akiyoshi; Jiménez-Borreguero, Luis J.; de la Pompa, José Luis

    2016-01-01

    Ventricular chambers are essential for the rhythmic contraction and relaxation occurring in every heartbeat throughout life. Congenital abnormalities in ventricular chamber formation cause severe human heart defects. How the early trabecular meshwork of myocardial fibres forms and subsequently develops into mature chambers is poorly understood. We show that Notch signalling first connects chamber endocardium and myocardium to sustain trabeculation, and later coordinates ventricular patterning and compaction with coronary vessel development to generate the mature chamber, through a temporal sequence of ligand signalling determined by the glycosyltransferase manic fringe (MFng). Early endocardial expression of MFng promotes Dll4–Notch1 signalling, which induces trabeculation in the developing ventricle. Ventricular maturation and compaction require MFng and Dll4 downregulation in the endocardium, which allows myocardial Jag1 and Jag2 signalling to Notch1 in this tissue. Perturbation of this signalling equilibrium severely disrupts heart chamber formation. Our results open a new research avenue into the pathogenesis of cardiomyopathies. PMID:26641715

  11. An airborne isothermal haze chamber

    NASA Technical Reports Server (NTRS)

    Hindman, E. E.

    1981-01-01

    Thermal gradient diffusion cloud chambers (TGDCC) are used to determine the concentrations of cloud condensation nuclei (CCN) with critical supersaturations greater than or equal to about 0.2%. The CCN concentrations measured with the airborne IHC were lower than theoretically predicted by factors ranging between 7.9 and 9.0. The CCN concentrations measured with the airborne IHC were lower than the concentrations measured with the larger laboratory IHC's by factors ranging between 3.9 and 7.5. The bounds of the supersaturation ranges of the airborne IHC and the CSU-Mee TGDCC do not overlap. Nevertheless, the slopes of the interpolated data between the bounds agree favorably with the theoretical slopes.

  12. Drift chamber tracking with neural networks

    SciTech Connect

    Lindsey, C.S.; Denby, B.; Haggerty, H.

    1992-10-01

    We discuss drift chamber tracking with a commercial log VLSI neural network chip. Voltages proportional to the drift times in a 4-layer drift chamber were presented to the Intel ETANN chip. The network was trained to provide the intercept and slope of straight tracks traversing the chamber. The outputs were recorded and later compared off line to conventional track fits. Two types of network architectures were studied. Applications of neural network tracking to high energy physics detector triggers is discussed.

  13. IFE Chamber Technology - Status and Future Challenges

    SciTech Connect

    Meier, W R; Raffrary, A R; Abdel-Khalik, S; Kulcinski, G; Latkowski, J F; Najmabadi, F; Olson, C L; Peterson, P F; Ying, A; Yoda, M

    2002-11-15

    Significant progress has been made on addressing critical issues for inertial fusion energy (IFE) chambers for heavy-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry-wall (currently favored for laser IFE), wetted-wall (applicable to both laser and ion drivers), and thick-liquid-wall favored by heavy ion and z-pinch drivers. Recent progress and remaining challenges in developing IFE chambers are reviewed.

  14. Free-Flow Open-Chamber Electrophoresis

    NASA Technical Reports Server (NTRS)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Free-flow open-chamber electrophoresis variant of free-flow electrophoresis performed in chamber with open ends and in which velocity of electro-osmotic flow adjusted equal to and opposite mean electrophoretic velocity of sample. Particles having electrophoretic mobilities greater than mean mobility of sample particles move toward cathode, those with mobilities less move toward anode. Technique applied to separation of components of mixtures of biologically important substances. Sensitivity enhanced by use of tapered chamber.

  15. Fluidized wall for protecting fusion chamber walls

    DOEpatents

    Maniscalco, James A.; Meier, Wayne R.

    1982-01-01

    Apparatus for protecting the inner wall of a fusion chamber from microexplosion debris, x-rays, neutrons, etc. produced by deuterium-tritium (DT) targets imploded within the fusion chamber. The apparatus utilizes a fluidized wall similar to a waterfall comprising liquid lithium or solid pellets of lithium-ceramic, the waterfall forming a blanket to prevent damage of the structural materials of the chamber.

  16. Engineering verification of the biomass production chamber

    NASA Technical Reports Server (NTRS)

    Prince, R. P.; Knott, W. M., III; Sager, J. C.; Jones, J. D.

    1992-01-01

    The requirements for life support systems, both biological and physical-chemical, for long-term human attended space missions are under serious study throughout NASA. The KSC 'breadboard' project has focused on biomass production using higher plants for atmospheric regeneration and food production in a special biomass production chamber. This chamber is designed to provide information on food crop growth rate, contaminants in the chamber that alter plant growth requirements for atmospheric regeneration, carbon dioxide consumption, oxygen production, and water utilization. The shape and size, mass, and energy requirements in relation to the overall integrity of the biomass production chamber are under constant study.

  17. The NASA Ames Controlled Environment Research Chamber: Present status

    NASA Technical Reports Server (NTRS)

    Gross, Anthony R.; Korsmeyer, David J.; Harper, Lynn D.; Force, Edwin L.

    1994-01-01

    The Controlled Environment Research Chamber (CERC) at the NASA Ames Research Center was created for early-on investigation of promising new technologies for life support of advanced space exploration missions. The CERC facility is being used to address the advanced technology requirements necessary to implement an integrated working and living environment for a planetary habitat. The CERC, along with a human-powered centrifuge, a planetary terrain simulator, advanced displays, and a virtual reality, is able to develop and demonstrate applicable technologies for future planetary exploration. There will be several robotic mechanisms performing exploration tasks external to the habitat that will be controlled through the virtual environment to provide representative workloads for the crew. Finally, there will be a discussion of innovative new multidisciplinary test facilities, and how effective they are to the investigation of the wide range of human and machine problems inherent in exploration missions.

  18. The NASA Ames Controlled Environment Research Chamber - Present status

    NASA Technical Reports Server (NTRS)

    Gross, Anthony R.; Korsmeyer, David J.; Harper, Lynn D.; Force, Edwin L.

    1994-01-01

    The Controlled Environment Research Chamber (CERC) at the NASA Ames Research Center was created for early-on investigation of promising new technologies for life support of advanced space exploration missions. The CERC facility is being used to address the advanced technology requirements necessary to implement an integrated working and living environment for a planetary habitat. The CERC, along with a human-powered centrifuge, a planetary terrain simulator, advanced displays, and a virtual reality capability, is able to develop and demonstrate applicable technologies for future planetary exploration. There will be several robotic mechanisms performing exploration taskes external to the habitat that will be controlled through the virtual environment to provide representative workloads for the crew. Finally, there will be a discussion of innovative new multidisciplinary test facilities, and how effective they are to the investigation of the wide range of human and machine problems inherent in exploration missions.

  19. The design and verification of a MEMS combustor chamber

    NASA Astrophysics Data System (ADS)

    Meadors, Constance Y.

    A pre-combustion micro-mixing chamber has been designed as a component of the University of Arkansas at Little Rock's (UALR) proposed complete microelectromechanical (MEMS) hybrid rocket on a silicon chip. A MEMS pre-combustion mixer allows identification of pressures and flow rates for stochiometric mixing of combustion gases. The pre-combustion mixer has been designed to interface with a mass spectrometer for detection and characterization of combustion reactants and products as the first stage of a UALR hybrid micro-thruster. This research focuses on the design, fabrication, and validation of a pre-combustion micro-mixer that satisfies the requirements of MEMS micro-spacecraft and operates in space conditions. Gases are injected into the chamber via inlet ports and ignited. The combustion products are carried from the device to an online mass spectrometer to verify and quantify the combustion reaction. MEMS design techniques and fabrication facilities are utilized to design a micromixer. The mixing chamber has been qualitatively and quantitatively verified through combustion and mass spectrometry. The detection of water using the mass spectrometer confirmed mixing and combustion, confirming the ability to mix and ignite combustion gases under vacuum conditions. Therefore, for space applications a MEMS combustor may be utilized.

  20. Response of ionization chamber based pocket dosimeter to beta radiation.

    PubMed

    Kumar, Munish; Gupta, Anil; Pradhan, S M; Bakshi, A K; Chougaonkar, M P; Babu, D A R

    2013-12-01

    Quantitative estimate of the response of ionization chamber based pocket dosimeters (DRDs) to various beta sources was performed. It has been established that the ionization chamber based pocket dosimeters do not respond to beta particles having energy (Emax)<1 MeV and same was verified using (147)Pm, (85)Kr and (204)Tl beta sources. However, for beta particles having energy >1 MeV, the DRDs exhibit measureable response and the values are ~8%, ~14% and ~27% per mSv for natural uranium, (90)Sr/(90)Y and (106)Ru/(106)Rh beta sources respectively. As the energy of the beta particles increases, the response also increases. The response of DRDs to beta particles having energy>1 MeV arises due to the fact that the thickness of the chamber walls is less than the maximum range of beta particles. This may also be one of the reasons for disparity between doses measured with passive/legal dosimeters (TLDs) and DRDs in those situations in which radiation workers are exposed to mixed field of gamma photons and beta particles especially at uranium processing plants, nuclear (power and research) reactors, waste management facilities and fuel reprocessing plants etc. The paper provides the reason (technical) for disparity between the doses recorded by TLDs and DRDs in mixed field of photons and beta particles.

  1. study on trace contaminants control assembly for sealed environment chamber

    NASA Astrophysics Data System (ADS)

    Pang, L. P.; Wang, J.; Liu, L. K.; Liu, H.

    The biological and Physicochemical P C life support technologies are all important parts to establish a human Closed Ecological Life Support System CELSS for long-duration mission The latter has the advantages of lower power consumption lower mass and higher efficiency therefore researchers often incorporate the use of biological systems with P C life support technologies to continuously recycle air water and part of the solid waste stream generated such as the Russian BLSS and the NASA-sponsored Lunar-Mars Life Support Test Project LMLSTP In short these tests were very successful in integrating biological and P C life support technologies for long-duration life support Therefore we should use a combination of integrated biological with P C life support technologies in a human CELSS Human construction materials plants animals and soils release much trace toxic gases in a CELSS and they will inhibit plant growth and badly affect human health when their concentrations rise over their threshold levels The effect of biological trace contaminant control technologies is slower especially for a human sealed chamber because human produce much more methane and other contaminants A regenerative Trace Contaminant Control Subsystem TCCS with P C technology is a more important part in this case to control quickly the airborne contaminants levels and assure human in good condition in a sealed chamber This paper describes a trace contaminant control test facility incorporated a 8 m3 sealed environment chamber a regenerative TCCS with P C

  2. LAYOUT AND SIZING OF ESF ALCOVES AND REFUGE CHAMBERS

    SciTech Connect

    John Beesley and Romeo S. Jurani

    1995-08-25

    The purpose of this analysis is to establish size requirements and approximate locations of Exploratory Studies Facility (ESF) test and operations alcoves, including refuge chambers during construction of the Topopah Spring (TS) loop. Preliminary conceptual layouts for non-deferred test alcoves will be developed to examine construction feasibility based on current test plans and available equipment. The final location and configuration layout for alcoves will be developed when in-situ rock conditions can be visually determined. This will be after the TBM has excavated beyond the alcove location and the rock has been exposed. The analysis will examine the need for construction of walkways and electrical alcoves in the ramps and main drift. Niches that may be required to accommodate conveyor booster drives and alignments are not included in this analysis. The analysis will develop design criteria for refuge chambers to meet MSHA requirements and will examine the strategic location of refuge chambers based on their potential use in various ESF fire scenarios. This document supersedes DI:BABE00000-01717-0200-00003 Rev 01, ''TS North Ramp Alcove and Stubout Location Analysis'' in its entirety (Reference 5-6).

  3. Modeling smog chamber measurements of vehicle exhaust VOC reactivities

    SciTech Connect

    Chang, T.Y.; Nance, B.I.; Kelly, N.A.

    1997-12-31

    Vehicle exhaust VOC reactivities, measured at GM`s smog chamber facility, have been modeled using the SAPRC93 photochemical mechanism. The vehicle exhaust mixtures were generated by a single vehicle run over a portion of the Federal Test Procedure using three Auto/Oil reformulated test gasolines. For each run, up to 156 individual VOC species were identified. Initial HONO concentrations are needed to simulate reactivity measurement runs. (HONO is expected to be generated in a Tedlar bag holding the exhaust sample prior to its transfer to the smog chambers.) Measured and simulated relative incremental reactivities for the three exhaust mixtures are highly consistent. However, measured relative incremental reactivities are more sensitive to fuel effects than simulated ones. The maximum incremental reactivity (MIR)-based relative incremental reactivities, derived from individual species concentrations and MIR factors, are very close to simulated ones. A number of sensitivity simulation runs have been carried out to investigate the impact of HONO and other variables. Results show that relative reactivities of actual vehicle exhaust emissions can be measured by chamber runs in spite of the HONO effect.

  4. ATRF Ribbon-Cutting Ceremony Coincides with Chamber of Commerce Centennial Gala | Poster

    Cancer.gov

    By Frank Blanchard, Staff Writer U.S. Rep. Roscoe Bartlett, NCI Deputy Director for Management John Czajkowski, and SAIC Corporate Chief Executive Officer (CEO) John Jumper were joined by representatives of the Frederick County Chamber of Commerce in cutting the ribbon for the National Cancer Institute’s Advanced Technology Research Facility (ATRF).

  5. FULL-SCALE CHAMBER INVESTIGATION AND SIMULATION OF AIR FRESHENER EMISSIONS IN THE PRESENCE OF OZONE

    EPA Science Inventory

    The paper discusses results of tests, conducted in the EPA large chamber facility, determining emissions and chemical degradation of volatile organic compounds (VOCs) from one electrical plug-in type pine-scented air freshener in the presence of ozone supplied by a device markete...

  6. Studying Phototropism Using a Small Growth Chamber.

    ERIC Educational Resources Information Center

    Fisher, Maryanna, F.; Llewellyn, Gerald C.

    1978-01-01

    Describes a simple and inexpensive way to construct two small growth chambers for studying phototropism in the science classroom. One chamber is designed to illustrate how plants grow around obstacles to reach light and the other to illustrate directional light responses. (HM)

  7. 21 CFR 868.5470 - Hyperbaric chamber.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hyperbaric chamber. 868.5470 Section 868.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5470 Hyperbaric chamber. (a) Identification....

  8. 21 CFR 868.5470 - Hyperbaric chamber.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hyperbaric chamber. 868.5470 Section 868.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5470 Hyperbaric chamber. (a) Identification....

  9. 21 CFR 868.5470 - Hyperbaric chamber.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hyperbaric chamber. 868.5470 Section 868.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5470 Hyperbaric chamber. (a) Identification....

  10. 21 CFR 868.5470 - Hyperbaric chamber.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hyperbaric chamber. 868.5470 Section 868.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5470 Hyperbaric chamber. (a) Identification....

  11. 21 CFR 866.2120 - Anaerobic chamber.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anaerobic chamber. 866.2120 Section 866.2120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber....

  12. 21 CFR 866.2120 - Anaerobic chamber.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Anaerobic chamber. 866.2120 Section 866.2120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber....

  13. 21 CFR 866.2120 - Anaerobic chamber.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anaerobic chamber. 866.2120 Section 866.2120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber....

  14. 21 CFR 866.2120 - Anaerobic chamber.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Anaerobic chamber. 866.2120 Section 866.2120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber....

  15. 21 CFR 866.2120 - Anaerobic chamber.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Anaerobic chamber. 866.2120 Section 866.2120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber....

  16. Chamber Music's Lesson in Performing Confidence.

    ERIC Educational Resources Information Center

    Stubbs, Darrel W.

    1983-01-01

    Chamber music has the advantage of offering the student maximum exposure as an individual performer. The absence of a conductor means that the student assumes the role of interpreter, thereby gaining musical maturity. For these reasons, curriculum hours should be more evenly divided between chamber music and larger ensembles. (CS)

  17. Creating Chamber Music Enthusiasts in High School.

    ERIC Educational Resources Information Center

    Cummiskey, Cynthia

    1999-01-01

    Describes the Fairfield High School Chamber Music Honors Program for students in grades nine through twelve in Fairfield (Connecticut). Explains that the program's goal is to provide students with a positive experience in chamber music. Highlights the creation and the first two years of the program. (CMK)

  18. Promoting "Minds-on" Chamber Music Rehearsals

    ERIC Educational Resources Information Center

    Berg, Margaret H.

    2008-01-01

    Chamber music provides myriad opportunities to develop students' ability to think like professional musicians while engaged in the authentic task of working closely with and learning from peers. However, the potential for musical growth inherent in chamber music participation is often unrealized due to either a lack of teacher guidance and support…

  19. Incinerator system arrangement with dual scrubbing chambers

    SciTech Connect

    Domnitch, I.

    1987-01-13

    An incinerator arrangement is described comprising: an incinerator housing located near the lowest point in a building, the housing containing incinerator elements therein; a chute-flue having a first end in communication with the incinerator housing, a second end at the top of the building for evacuation of combustion gases to the atmosphere therethrough, and at least one intermediately located waste disposal opening through which waste is dropped into the incinerator housing; the incinerator elements including: a main combustion chamber, an opening between the main combustion chamber and the first end of the chute-flue and a flue-damper covering the opening. The flue-damper is biased in a closed position and being operable by the weight of waste to admit the waste into the combustion chamber; a scrubbing chamber located exteriorly along the top of the combustion chamber and having a first opening into the combustion chamber and a second opening into the chute-flue; and water spraying means in the scrubbing chamber for directing a water spray at the combustion gases to wash particulate matter from the gases before the gases enter the chute-flue whereby the water spraying means which are located adjacent the combustion chamber are protected against freezing and the elements.

  20. Compact ion chamber based neutron detector

    DOEpatents

    Derzon, Mark S.; Galambos, Paul C.; Renzi, Ronald F.

    2015-10-27

    A directional neutron detector has an ion chamber formed in a dielectric material; a signal electrode and a ground electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; readout circuitry which is electrically coupled to the signal and ground electrodes; and a signal processor electrically coupled to the readout circuitry. The ion chamber has a pair of substantially planar electrode surfaces. The chamber pressure of the neutron absorbing material is selected such that the reaction particle ion trail length for neutrons absorbed by the neutron absorbing material is equal to or less than the distance between the electrode surfaces. The signal processor is adapted to determine a path angle for each absorbed neutron based on the rise time of the corresponding pulse in a time-varying detector signal.

  1. Ionization-chamber smoke detector system

    DOEpatents

    Roe, Robert F.

    1976-10-19

    This invention relates to an improved smoke-detection system of the ionization-chamber type. In the preferred embodiment, the system utilizes a conventional detector head comprising a measuring ionization chamber, a reference ionization chamber, and a normally non-conductive gas triode for discharging when a threshold concentration of airborne particulates is present in the measuring chamber. The improved system is designed to reduce false alarms caused by fluctuations in ambient temperature. Means are provided for periodically firing the gas discharge triode and each time recording the triggering voltage required. A computer compares each triggering voltage with its predecessor. The computer is programmed to energize an alarm if the difference between the two compared voltages is a relatively large value indicative of particulates in the measuring chamber and to disregard smaller differences typically resulting from changes in ambient temperature.

  2. An atmospheric exposure chamber for small animals

    NASA Technical Reports Server (NTRS)

    Glaser, R. M.; Weiss, H. S.; Pitt, J. F.; Grimard, M.

    1982-01-01

    The purpose of this project was to design a long-term environmental exposure chamber for small animals. This chamber is capable of producing hypoxic, normoxic and hyperoxic atmospheres which are closely regulated. The chamber, which is of the recycling type, is fashioned after clear plastic germ-free isolators. Oxygen concentration is set and controlled by a paramagnetic O2 analyzer and a 3-way solenoid valve. In this way either O2 or N2 may be provided to the system by way of negative O2 feedback. Relative humidity is maintained at 40-50 percent by a refrigeration type dryer. Carbon dioxide is absorbed by indicating soda lime. A diaphragm pump continuously circulates chamber gas at a high enough flow rate to prevent buildup of CO2 and humidity. This chamber has been used for numerous studies which involve prolonged exposure of small animals to various O2 concentrations.

  3. Note: Small anaerobic chamber for optical spectroscopy

    SciTech Connect

    Chauvet, Adrien A. P. Chergui, Majed; Agarwal, Rachna; Cramer, William A.

    2015-10-15

    The study of oxygen-sensitive biological samples requires an effective control of the atmosphere in which they are housed. In this aim however, no commercial anaerobic chamber is adequate to solely enclose the sample and small enough to fit in a compact spectroscopic system with which analysis can be performed. Furthermore, spectroscopic analysis requires the probe beam to pass through the whole chamber, introducing a requirement for adequate windows. In response to these challenges, we present a 1 l anaerobic chamber that is suitable for broad-band spectroscopic analysis. This chamber has the advantage of (1) providing access, via a septum, to the sample and (2) allows the sample position to be adjusted while keeping the chamber fixed and hermetic during the experiment.

  4. The INAF/IAPS Plasma Chamber for ionospheric simulation experiment

    NASA Astrophysics Data System (ADS)

    Diego, Piero

    2016-04-01

    The plasma chamber is particularly suitable to perform studies for the following applications: - plasma compatibility and functional tests on payloads envisioned to operate in the ionosphere (e.g. sensors onboard satellites, exposed to the external plasma environment); - calibration/testing of plasma diagnostic sensors; - characterization and compatibility tests on components for space applications (e.g. optical elements, harness, satellite paints, photo-voltaic cells, etc.); - experiments on satellite charging in a space plasma environment; - tests on active experiments which use ion, electron or plasma sources (ion thrusters, hollow cathodes, field effect emitters, plasma contactors, etc.); - possible studies relevant to fundamental space plasma physics. The facility consists of a large volume vacuum tank (a cylinder of length 4.5 m and diameter 1.7 m) equipped with a Kaufman type plasma source, operating with Argon gas, capable to generate a plasma beam with parameters (i.e. density and electron temperature) close to the values encountered in the ionosphere at F layer altitudes. The plasma beam (A+ ions and electrons) is accelerated into the chamber at a velocity that reproduces the relative motion between an orbiting satellite and the ionosphere (≈ 8 km/s). This feature, in particular, allows laboratory simulations of the actual compression and depletion phenomena which take place in the ram and wake regions around satellites moving through the ionosphere. The reproduced plasma environment is monitored using Langmuir Probes (LP) and Retarding Potential Analyzers (RPA). These sensors can be automatically moved within the experimental space using a sled mechanism. Such a feature allows the acquisition of the plasma parameters all around the space payload installed into the chamber for testing. The facility is currently in use to test the payloads of CSES satellite (Chinese Seismic Electromagnetic Satellite) devoted to plasma parameters and electric field

  5. RADIATION MONITOR CONTAINING TWO CONCENTRIC IONIZATION CHAMBERS AND MEANS FOR INSULATING THE SEPARATE CHAMBERS

    DOEpatents

    Braestrup, C.B.; Mooney, R.T.

    1964-01-21

    This invention relates to a portable radiation monitor containing two concentric ionization chambers which permit the use of standard charging and reading devices. It is particularly adapted as a personnel x-ray dosimeter and to this end comprises a small thin walled, cylindrical conductor forming an inner energy dependent chamber, a small thin walled, cylindrical conductor forming an outer energy independent chamber, and polymeric insulation means which insulates said chambers from each other and holds the chambers together with exposed connections in a simple, trouble-free, and compact assembly substantially without variation in directional response. (AEC)

  6. PSL Icing Facility Upgrade Overview

    NASA Technical Reports Server (NTRS)

    Griffin, Thomas A.; Dicki, Dennis J.; Lizanich, Paul J.

    2014-01-01

    The NASA Glenn Research Center Propulsion Systems Lab (PSL) was recently upgraded to perform engine inlet ice crystal testing in an altitude environment. The system installed 10 spray bars in the inlet plenum for ice crystal generation using 222 spray nozzles. As an altitude test chamber, the PSL is capable of simulating icing events at altitude in a groundtest facility. The system was designed to operate at altitudes from 4,000 to 40,000 ft at Mach numbers up to 0.8M and inlet total temperatures from -60 to +15 degF. This paper and presentation will be part of a series of presentations on PSL Icing and will cover the development of the icing capability through design, developmental testing, installation, initial calibration, and validation engine testing. Information will be presented on the design criteria and process, spray bar developmental testing at Cox and Co., system capabilities, and initial calibration and engine validation test. The PSL icing system was designed to provide NASA and the icing community with a facility that could be used for research studies of engine icing by duplicating in-flight events in a controlled ground-test facility. With the system and the altitude chamber we can produce flight conditions and cloud environments to simulate those encountered in flight. The icing system can be controlled to set various cloud uniformities, droplet median volumetric diameter (MVD), and icing water content (IWC) through a wide variety of conditions. The PSL chamber can set altitudes, Mach numbers, and temperatures of interest to the icing community and also has the instrumentation capability of measuring engine performance during icing testing. PSL last year completed the calibration and initial engine validation of the facility utilizing a Honeywell ALF502-R5 engine and has duplicated in-flight roll back conditions experienced during flight testing. This paper will summarize the modifications and buildup of the facility to accomplish these tests.

  7. The emulsion chamber technology experiment

    NASA Technical Reports Server (NTRS)

    Gregory, John C.

    1992-01-01

    Photographic emulsion has the unique property of recording tracks of ionizing particles with a spatial precision of 1 micron, while also being capable of deployment over detector areas of square meters or 10's of square meters. Detectors are passive, their cost to fly in Space is a fraction of that of instruments of similar collecting. A major problem in their continued use has been the labor intensiveness of data retrieval by traditional microscope methods. Two factors changing the acceptability of emulsion technology in space are the astronomical costs of flying large electronic instruments such as ionization calorimeters in Space, and the power and low cost of computers, a small revolution in the laboratory microscope data-taking. Our group at UAH made measurements of the high energy composition and spectra of cosmic rays. The Marshall group has also specialized in space radiation dosimetry. Ionization calorimeters, using alternating layers of lead and photographic emulsion, to measure particle energies up to 10(exp 15) eV were developed. Ten balloon flights were performed with them. No such calorimeters have ever flown in orbit. In the ECT program, a small emulsion chamber was developed and will be flown on the Shuttle mission OAST-2 to resolve the principal technological questions concerning space exposures. These include assessments of: (1) pre-flight and orbital exposure to background radiation, including both self-shielding and secondary particle generation; the practical limit to exposure time in space can then be determined; (2) dynamics of stack to optimize design for launch and weightlessness; and (3) thermal and vacuum constraints on emulsion performance. All these effects are cumulative and affect our ability to perform scientific measurements but cannot be adequately predicted by available methods.

  8. A telescience monitoring and control concept for a CELSS plant growth chamber

    NASA Technical Reports Server (NTRS)

    Rasmussen, Daryl N.; Mian, Arshad

    1989-01-01

    Consideration is given to the use of telescience to monitor and control a Space Station CELSS plant growth chamber (PGC). The proposed telescience control system contains controllers for PGC subsystems, a local master controller, and remote controllers. The benefits of telescience are discussed and the functional requirements of the PGC are outlined. A typical monitoring and control scenario is described. It is suggested that the proposed concept would provide remote access to a ground-based CELSS research facility, Space Station plant growth facilities, lunar-based CELSS facilities, and manned interplanetary spacecraft.

  9. Investigating 14CO2 chamber methodologies

    NASA Astrophysics Data System (ADS)

    Egan, J. E.; Phillips, C. L.; Nickerson, N. R.; Risk, D. A.

    2012-12-01

    The radiogenic isotope of carbon (14C) is an exceptionally useful tool in studying soil respired CO2, providing information about soil turnover rates, depths of production and the biological sources of production through partitioning. Unfortunately, little work has been done to thoroughly investigate the possibility of inherent biases in the current measurement techniques for 14CO2, caused by disturbances to the soil's natural diffusive regime, because of high costs and sampling logistics. Our aim in this study is to investigate the degree of bias present in the current sampling methodologies using a numerical model and laboratory calibration device. Four chamber techniques were tested numerically with varying fraction modern of production, δ13C of production, collar lengths, flux rates and diffusivities. Two of the chambers were then tested on the lab calibration device. One of these chambers, Iso-FD, has recently been tested for its use as a 13CO2 chamber and it does not induce gas transport fractionation biases present in other 13CO2 sampling methodologies. We then implemented it in the field to test its application as a 14CO2 chamber because of its excellent performance as a 13CO2chamber. Presented here are the results from the numerical modeling experiment, the laboratory calibration experiment and preliminary field results from the Iso-FD chamber.

  10. Performance evaluation of multi sampling ionization chamber for heavy ion beams by comparison with GEANT4 simulation

    NASA Astrophysics Data System (ADS)

    Kanke, Yuki; Himac H093 Collaboration

    2014-09-01

    In high-energy heavy-ion accelerator facilities, multi sampling ionization chambers are often used for the identification of the atomic number Z by detecting the energy deposit in it. In the study at GSI, the picture of the escape of secondary electrons, δ rays, from the ionization chamber explains the experimental data of pulse-height resolution. If this picture is correct, the pulse-height resolution should depend on the effective area of the ionization chamber. The experiment have been performed at NIRS-HIMAC. The pulse-height resolutions of two ionization chambers with different effective area were compared by using a 400-MeV/u Ni beam and their fragments. The difference in the pulse-height resolutions was observed. By comparison with the GEANT4 simulation including the δ-rays emission, the performance of the ionization chamber have been evaluated.

  11. The JPL Molecular Contamination Investigation Facility

    NASA Technical Reports Server (NTRS)

    Taylor, Daniel M.; Soules, David; Osborn, David

    1990-01-01

    The Molecular Contamination Investigation Facility (MCIF) is discussed in terms of its use for improving the far-UV performance of a camera and its broader applications. The MCIF incorporates two independent vacuum systems with sample isolation chambers and regulated heat exchangers as well as three quartz-crystal microbalances (QCMs) and a residual gas analyzer. One cryogenic QCM is heat sunk into an LN2 heat exchanger, while the others are thermoelectrically controlled and are heat sunk into a regulated heat exchanger. Outgas accumulation can be measured at three surface temperatures between -180 and 80 C simultaneously, and results are presented for the testing of 34 samples in a large-chambered system and 22 samples in a system with a smaller chamber. The MCIF results provide a database for fabrication processes, material selection, maximum bakeout temperatures, and the development of an ultraclean bakeout chamber.

  12. Vapor wall deposition in Teflon chambers

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Schwantes, R. H.; McVay, R. C.; Lignell, H.; Coggon, M. M.; Flagan, R. C.; Seinfeld, J. H.

    2014-10-01

    Teflon chambers are ubiquitous in studies of atmospheric chemistry. Secondary organic aerosol (SOA) formation can be substantially underestimated owing to deposition of SOA-forming compounds to chamber walls. We present here an experimental protocol to constrain the nature of wall deposition of organic vapors in Teflon chambers. We measured the wall deposition rates of 25 oxidized organic compounds generated from the photooxidation of isoprene, toluene, α-pinene, and dodecane in two chambers that had been extensively used and in two new unused chambers. We found that the extent of prior use of the chamber did not significantly affect the sorption behavior of the Teflon films. The dominant parameter governing the extent of wall deposition of a compound is its wall accommodation coefficient (αw,i), which can be correlated through its volatility (Ci*) with the number of carbons (nC) and oxygens (nO) in the molecule. Among the 25 compounds studied, the maximum wall deposition rate is approached by the most highly oxygenated and least volatile compounds. The extent to which vapor wall deposition impacts measured SOA yields depends on the competition between uptake of organic vapors by suspended particles and chamber walls. Gas-particle equilibrium partitioning is established relatively rapidly in the presence of perfect accommodation of organic vapors onto particles or when a sufficiently large concentration of suspended particles is present. The timescale associated with vapor wall deposition can vary from minutes to hours depending on the value of αw,i. For volatile and intermediate volatility organic compounds (small αw,i), gas-particle partitioning will be dominant for typical particle number concentrations in chamber experiments. For large αw,i, vapor transport to particles is suppressed by competition with the chamber walls even with perfect particle accommodation.

  13. Gas Electron Multiplier (GEM) Chamber Characteristics Test

    SciTech Connect

    Yu, Jaehoon; White, Andy; Park, Seongtae; Hahn, Changhie; Baldeloma, Edwin; Tran, Nam; McIntire, Austin; Soha, Aria; /Fermilab

    2011-01-11

    Gas Electron Multipliers (GEMs) have been used in many HEP experiments as tracking detectors. They are sensitive to X-rays which allows use beyond that of HEP. The UTA High Energy group has been working on using GEMs as the sensitive gap detector in a DHCAL for the ILC. The physics goals at the ILC put a stringent requirement on detector performance. Especially the precision required for jet mass and positions demands an unprecedented jet energy resolution to hadronic calorimeters. A solution to meet this requirement is using the Particle Flow Algorithm (PFA). In order for PFA to work well, high calorimeter granularity is necessary. Previous studies based on GEANT simulations using GEM DHCAL gave confidence on the performance of GEM in the sensitive gap in a sampling calorimeter and its use as a DHCAL in PFA. The UTA HEP team has built several GEM prototype chambers, including the current 30cm x 30cm chamber integrated with the SLAC-developed 64 channel kPiX analog readout chip. This chamber has been tested on the bench using radioactive sources and cosmic ray muons. In order to have fuller understanding of various chamber characteristics, the experiments plan to expose 1-3 GEM chambers of dimension 35cm x 35cm x 5cm with 1cm x 1cm pad granularity with 64 channel 2-D simultaneous readout using the kPiX chip. In this experiment the experiments pan to measure MiP signal height, chamber absolute efficiencies, chamber gain versus high voltage across the GEM gap, the uniformity of the chamber across the 8cm x 8cm area, cross talk and its distance dependence to the triggered pad, chamber rate capabilities, and the maximum pad occupancy rate.

  14. Vapor wall deposition in Teflon chambers

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Schwantes, R. H.; McVay, R. C.; Lignell, H.; Coggon, M. M.; Flagan, R. C.; Seinfeld, J. H.

    2015-04-01

    Teflon chambers are ubiquitous in studies of atmospheric chemistry. Secondary organic aerosol (SOA) formation can be underestimated, owing to deposition of SOA-forming vapors to the chamber wall. We present here an experimental protocol and a model framework to constrain the vapor-wall interactions in Teflon chambers. We measured the wall deposition rates of 25 oxidized organic compounds generated from the photooxidation of isoprene, toluene, α-pinene, and dodecane in two chambers that had been extensively used and in two new unused chambers. We found that the extent of prior use of the chamber did not significantly affect the sorption behavior of the Teflon films. Among the 25 compounds studied, the maximum wall deposition rate is exhibited by the most highly oxygenated and least volatile compounds. By optimizing the model output to the observed vapor decay profiles, we identified that the dominant parameter governing the extent of wall deposition of a compound is its wall accommodation coefficient (αwi), which can be correlated through its volatility with the number of carbons and oxygens in the molecule. By doing so, the wall-induced deposition rate of intermediate/semi-volatile organic vapors can be reasonably predicted based on their molecular constituency. The extent to which vapor wall deposition impacts measured SOA yields depends on the competition between uptake of organic vapors by suspended particles and the chamber wall. The timescale associated with vapor wall deposition can vary from minutes to hours depending on the value of αw,i. For volatile and intermediate volatility organic compounds (small αw,i), gas-particle partitioning will dominate wall deposition for typical particle number concentrations in chamber experiments. For compounds characterized by relatively large αw,i, vapor transport to particles is suppressed by competition with the chamber wall even with perfect particle accommodation.

  15. Making MUSIC: A multiple sampling ionization chamber

    NASA Astrophysics Data System (ADS)

    Shumard, B.; Henderson, D. J.; Rehm, K. E.; Tang, X. D.

    2007-08-01

    A multiple sampling ionization chamber (MUSIC) was developed for use in conjunction with the Atlas scattering chamber (ATSCAT). This chamber was developed to study the (α, p) reaction in stable and radioactive beams. The gas filled ionization chamber is used as a target and detector for both particles in the outgoing channel (p + beam particles for elastic scattering or p + residual nucleus for (α, p) reactions). The MUSIC detector is followed by a Si array to provide a trigger for anode events. The anode events are gated by a gating grid so that only (α, p) reactions where the proton reaches the Si detector result in an anode event. The MUSIC detector is a segmented ionization chamber. The active length of the chamber is 11.95 in. and is divided into 16 equal anode segments (3.5 in. × 0.70 in. with 0.3 in. spacing between pads). The dead area of the chamber was reduced by the addition of a Delrin snout that extends 0.875 in. into the chamber from the front face, to which a mylar window is affixed. 0.5 in. above the anode is a Frisch grid that is held at ground potential. 0.5 in. above the Frisch grid is a gating grid. The gating grid functions as a drift electron barrier, effectively halting the gathering of signals. Setting two sets of alternating wires at differing potentials creates a lateral electric field which traps the drift electrons, stopping the collection of anode signals. The chamber also has a reinforced mylar exit window separating the Si array from the target gas. This allows protons from the (α, p) reaction to be detected. The detection of these protons opens the gating grid to allow the drift electrons released from the ionizing gas during the (α, p) reaction to reach the anode segment below the reaction.

  16. The Japanese Radon and Thoron Reference Chambers

    SciTech Connect

    Tokonami, Shinji; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Takahashi, Hiroyuki; Miyahara, Nobuyuki

    2008-08-07

    Passive detectors used for large-scale and long-term surveys are generally calibrated in a well-controlled environment such as a radon chamber. It has been also pointed out that some of them are sensitive to thoron. Thus it is necessary to check the thoron contribution to the detector response with the proposed or similar test before practical use. The NIRS accommodates radon/aerosol and thoron chambers for quality assurance and quality control of radon measurements. Thus both chambers work so well that they can supply us with the calibration technique and consequently, a good level of knowledge of the radon and thoron issue.

  17. Performance of NIRS Thoron Chamber System

    NASA Astrophysics Data System (ADS)

    Sorimachi, Atsuyuki; Tokonami, Shinji; Takahashi, Hiroyuki; Kobayashi, Yosuke

    2008-08-01

    In order to carry out thoron sensitivity test for passive radon detectors, a thoron chamber system has been set up at NIRS, Japan. The thoron chamber system consists of four components: the exposure, monitoring, calibration, and humidity control systems, which was mounted in this study due to humidity dependence on the thoron concentration emanated from lantern mantles as the thoron source. The thoron concentration in the thoron chamber is controlled by humidity passed through the thoron source and the weight of the lantern mantle.

  18. Simple cloud chambers using gel ice packs

    NASA Astrophysics Data System (ADS)

    Kamata, Masahiro; Kubota, Miki

    2012-07-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry ice or liquid nitrogen. The gel can be frozen in normal domestic freezers, and can be used repeatedly by re-freezing. The tracks of alpha-ray particles can be observed continuously for about 20 min, and the operation is simple and easy.

  19. Francium Trapping Facility at TRIUMF for weak interaction studies

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Orozco, L. A.; Collister, R.; Gwinner, G.; Tandecki, M.; Behr, J. A.; Pearson, M. R.; Gomez, E.; Aubin, S.; Frpnc Collaboration

    2014-05-01

    We present the current status of the Francium Trapping Facility at TRIUMF. After successfully commissioning the capture chamber we are now in the process of finishing the science chamber where weak interaction measurements on Fr will be performed. We require transfer of the cold atoms from the capture chamber to the science chamber where they can be re-trapped for precision spectroscopy. The modular design of the science chamber allows for microwave studies for the anapole moment measurement and optical studies for the weak charge measurements using atomic parity non-conservation. We will present our current status and the plans for the commissioning run of the science chamber. Work supported by NSERC and NRC from Canada, NSF and DOE from USA, CONACYT from Mexico.

  20. 30 CFR 77.305 - Access to drying chambers, hot gas inlet chambers and ductwork; installation and maintenance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Access to drying chambers, hot gas inlet chambers and ductwork; installation and maintenance. 77.305 Section 77.305 Mineral Resources MINE SAFETY... drying chambers, hot gas inlet chambers and ductwork; installation and maintenance. Drying chambers,...

  1. 30 CFR 77.305 - Access to drying chambers, hot gas inlet chambers and ductwork; installation and maintenance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Access to drying chambers, hot gas inlet chambers and ductwork; installation and maintenance. 77.305 Section 77.305 Mineral Resources MINE SAFETY... drying chambers, hot gas inlet chambers and ductwork; installation and maintenance. Drying chambers,...

  2. The National Ignition Facility

    SciTech Connect

    Miller, G H; Moses, E I; Wuest, C R

    2004-02-06

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter-diameter target chamber and room for 100 diagnostics. NIF is the world's largest and most energetic laser experimental system, providing a scientific center to study inertial confinement fusion and matter at extreme energy densities and pressures. NIF's energetic laser beams will compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. Other NIF experiments will study physical processes at temperatures approaching 10{sup 8} K and 10{sup 11} bar; conditions that exist naturally only in the interior of stars and planets. NIF has completed the first phases of its laser commissioning program. The first four beams of NIF have generated 106 kilojoules in 23-ns pulses of infrared light and over 16 kJ in 3.5-ns pulses at the third harmonic (351 nm). NIF's target experimental systems are being commissioned and experiments have begun. This paper provides a detailed look the NIF laser systems, laser and optical performance, and results from recent laser commissioning shots. We follow this with a discussion of NIF's high-energy-density and inertial fusion experimental capabilities, the first experiments on NIF, and plans for future capabilities of this unique facility.

  3. The National Ignition Facility

    SciTech Connect

    Miller, G H; Moses, E I; Wuest, C R

    2004-06-03

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is a stadium-sized facility that, when completed in 2008, will contain a 192-beam, 1.8- Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter-diameter target chamber and room for 100 diagnostics. NIF is the world's largest and most energetic laser experimental system and will provide a scientific center to study inertial confinement fusion and matter at extreme energy densities and pressures. NIF's energetic laser beams will compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. Other NIF experiments will study physical processes at temperatures approaching 10{sup 8} K and 10{sup 11} bar; conditions that exist naturally only in the interior of stars and planets. NIF has completed the first phases of its laser commissioning program. The first four beams of NIF have generated 106 kilojoules in 23-ns pulses of infrared light and over 16 kJ in 3.5- ns pulses at the third harmonic (351 nm). NIF's target experimental systems are being commissioned and experiments have begun. This paper provides a detailed look the NIF laser systems, laser and optical performance, and results from recent laser commissioning shots. We follow this with a discussion of NIF's high-energy-density and inertial fusion experimental capabilities, the first experiments on NIF, and plans for future capabilities of this unique facility.

  4. Outdoor chamber study to test multi-day effects. Volume 3. Documentation for computer-readable environmental chamber data. Final report, August 1982-August 1984

    SciTech Connect

    Carter, W.P.L.; Dodd, M.C.; Long, W.D.; Atkinson, R.

    1984-12-01

    The smog chamber facilities of the University of California, Riverside were used to collect experimental data to assess the effects of multi-day irradiations on photochemical oxidant formation. This volume includes documentation on the computer-readable magnetic tape that contains all the data collected in the study. The tape is suitable for use by modelers to develop and test kinetic mechanisms of photochemical smog formation.

  5. 11. Detail view west from airlock chamber of typical refrigerator ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Detail view west from airlock chamber of typical refrigerator door into Trophic Chamber. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  6. DETAIL OF THE GROOVED RIM ON TOP FACE OF CHAMBER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF THE GROOVED RIM ON TOP FACE OF CHAMBER SHELL, ALTITUDE CHAMBER L, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  7. Construction of a fast ionization chamber for high-rate particle identification

    NASA Astrophysics Data System (ADS)

    Chae, K. Y.; Ahn, S.; Bardayan, D. W.; Chipps, K. A.; Manning, B.; Pain, S. D.; Peters, W. A.; Schmitt, K. T.; Smith, M. S.; Strauss, S. Y.

    2014-07-01

    A new gas-filled ionization chamber for high count rate particle identification has been constructed and commissioned at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL). To enhance the response time of the ionization chamber, a design utilizing a tilted entrance window and tilted electrodes was adopted, which is modified from an original design by Kimura et al. [1]. A maximum counting rate of ~700,000 particles per second has been achieved. The detector has been used for several radioactive beam measurements performed at the HRIBF.

  8. BOREAS TGB-3 CH4 and CO2 Chamber Flux Data over NSA Upland Sites

    NASA Technical Reports Server (NTRS)

    Savage, Kathleen; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Moore, Tim R.

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-3) team collected methane and carbon dioxide (CH4, CO2) chamber flux measurements at the Northern Study Area (NSA) Fen, Old Black Spruce (OBS), Young Jack Pine (YJP), and auxiliary sites along Gillam Road and the 1989 burn site. Gas samples were extracted from chambers and analyzed at the NSA lab facility approximately every 7 days during May to September 1994 and June to October 1996. The data are provided in tabular ASCII files.

  9. IFE thick liquid wall chamber dynamics: Governing mechanisms andmodeling and experimental capabilities

    SciTech Connect

    Raffray, A.R.; Meier, W.; Abdel-Khalik, S.; Bonazza, R.; Calderoni, P.; Debonnel, C.S.; Dragojlovic, Z.; El-Guebaly, L.; Haynes,D.; Latkowski, J.; Olson, C.; Peterson, P.F.; Reyes, S.; Sharpe, P.; Tillack, M.S.; Zaghloul, M.

    2005-01-24

    For thick liquid wall concepts, it is important to understand the different mechanisms affecting the chamber dynamics and the state of the chamber prior to each shot a compared with requirements from the driver and target. These include ablation mechanisms, vapor transport and control, possible aerosol formation, as well as protective jet behavior. This paper was motivated by a town meeting on this subject which helped identify the major issues, assess the latest results, review the capabilities of existing modeling and experimental facilities with respect to addressing remaining issues, and helping guide future analysis and R&D efforts; the paper covers these exact points.

  10. A multiple sampling time projection ionization chamber for nuclear fragment tracking and charge measurement

    NASA Astrophysics Data System (ADS)

    Bauer, G.; Bieser, F.; Brady, F. P.; Chance, J. C.; Christie, W. F.; Gilkes, M.; Lindenstruth, V.; Lynen, U.; Müller, Walter F. J.; Romero, J. L.; Sann, H.; Tull, C. E.; Warren, P.

    1997-02-01

    A detector has been developed for the tracking and charge measurement of the projectile fragment nuclei produced in relativistic nuclear collisions. This device, MUSIC II, is a second generation Multiple Sampling Ionization Chamber (MUSIC), and employs the principles of ionization and time projection chambers. It provides unique charge determination for charges Z≥6, and excellent track position measurement. MUSIC II has been used most recently with the EOS (Equation of State) TPC and other EOS Collaboration detectors. Earlier it was used with other systems in experiments at the Heavy Ion Superconducting Spectrometer (HISS) facility at Lawrence Berkeley Laboratory and the ALADIN spectrometer at GSI.

  11. LDCM TIRS: Cracking open the chamber

    NASA Video Gallery

    Engineers at Goddard Space Flight Center inspect and move the Thermal Infrared Sensor (TIRS) after two months of testing in the thermal vacuum chamber. TIRS completed its first round of thermal vac...

  12. Three dimensional thrust chamber life prediction

    NASA Technical Reports Server (NTRS)

    Armstrong, W. H.; Brogren, E. W.

    1976-01-01

    A study was performed to analytically determine the cyclic thermomechanical behavior and fatigue life of three configurations of a Plug Nozzle Thrust Chamber. This thrust chamber is a test model which represents the current trend in nozzle design calling for high performance coupled with weight and volume limitations as well as extended life for reusability. The study involved the use of different materials and material combinations to evaluate their application to the problem of low-cycle fatigue in the thrust chamber. The thermal and structural analyses were carried out on a three-dimensional basis. Results are presented which show plots of continuous temperature histories and temperature distributions at selected times during the operating cycle of the thrust chamber. Computed structural data show critical regions for low-cycle fatigue and the histories of strain within the regions for each operation cycle.

  13. Internal combustion engine with multiple combustion chambers

    SciTech Connect

    Gruenwald, D.J.

    1992-05-26

    This patent describes a two-cycle compression ignition engine. It comprises one cylinder, a reciprocable piston moveable in the cylinder, a piston connecting rod, a crankshaft for operation of the piston connecting rod, a cylinder head enclosing the cylinder, the upper surface of the piston and the enclosing surface of the cylinder head defining a cylinder clearance volume, a first combustion chamber and a second combustion chamber located in the cylinder head. This patent describes improvement in means for isolating the combustion process for one full 360{degrees} rotation of the crankshaft; wherein the combustion chambers alternatively provide for expansion of combustion products in the respective chambers into the cylinder volume near top dead center upon each revolution of the crankshaft.

  14. HYLIFE-II reactor chamber design refinements

    SciTech Connect

    House, P.A.

    1994-06-01

    Mechanical design features of the reactor chamber for the HYLIFE-II inertial confinement fusion power plant are presented. A combination of oscillating and steady, molten salt streams (Li{sub 2}BeF{sub 4}) are used for shielding and blast protection of the chamber walls. The system is designed for a 6 Hz repetition rate. Beam path clearing, between shots, is accomplished with the oscillating flow. The mechanism for generating the oscillating streams is described. A design configuration of the vessel wall allows adequate cooling and provides extra shielding to reduce thermal stresses to tolerable levels. The bottom portion of the reactor chamber is designed to minimize splash back of the high velocity (>12 m/s) salt streams and also recover up to half of the dynamic head. Cost estimates for a 1 GWe and 2 GWe reactor chamber are presented.

  15. Developing Cloud Chambers with High School Students

    NASA Astrophysics Data System (ADS)

    Ishizuka, Ryo; Tan, Nobuaki; Sato, Shoma; Zeze, Syoji

    The result and outcome of the cloud chamber project, which aims to develop a cloud chamber useful for science education is reported in detail. A project includes both three high school students and a teacher as a part of Super Science High School (SSH) program in our school. We develop a dry-ice-free cloud chamber using salt and ice (or snow). Technical details of the chamber are described. We also argue how the project have affected student's cognition, motivation, academic skills and behavior. The research project has taken steps of professional researchers, i.e., in planning research, applying fund, writing a paper and giving a talk in conferences. From interviews with students, we have learnt that such style of scientific activity is very effective in promoting student's motivation for learning science.

  16. Effectiveness of Chamber Music Ensemble Experience

    ERIC Educational Resources Information Center

    Zorn, Jay D.

    1973-01-01

    This investigation was concerned with the effectiveness of chamber music ensemble experience for certain members of a ninth grade band and the evaluation of the effectiveness in terms of performing abilities, cognitive learnings, and attitude changes. (Author)

  17. Rocket Combustion Chambers Resist Thermal Fatigue

    NASA Technical Reports Server (NTRS)

    Kazaroff, John M.; Jankovsky, Robert S.; Pavli, Albert J.

    1995-01-01

    Improved design concept developed for combustion chambers for rocket engines, described in three reports. Provides compliance allowing unrestrained thermal expansion in circumferential direction. Compliance lengthens life of rocket engine by reducing amount of thermal deformation caused by repeated firings.

  18. Tracking with wire chambers at the SSC

    SciTech Connect

    Hanson, G.G.; Gundy, M.C.; Palounek, A.P.T.

    1989-07-01

    Limitations placed on wire chambers by radiation damage and rate requirements in the SSC environment are reviewed. Possible conceptual designs for wire chamber tacking systems that meet these requirements are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 13 refs., 11 fig., 1 tab.

  19. Cloud chamber visualization of primary cosmic rays

    SciTech Connect

    Earl, James A.

    2013-02-07

    From 1948 until 1963, cloud chambers were carried to the top of the atmosphere by balloons. From these flights, which were begun by Edward P. Ney at the University of Minnesota, came the following results: discovery of heavy cosmic ray nuclei, development of scintillation and cherenkov detectors, discovery of cosmic ray electrons, and studies of solar proton events. The history of that era is illustrated here by cloud chamber photographs of primary cosmic rays.

  20. A model to forecast magma chamber rupture

    NASA Astrophysics Data System (ADS)

    Browning, John; Drymoni, Kyriaki; Gudmundsson, Agust

    2016-04-01

    An understanding of the amount of magma available to supply any given eruption is useful for determining the potential eruption magnitude and duration. Geodetic measurements and inversion techniques are often used to constrain volume changes within magma chambers, as well as constrain location and depth, but such models are incapable of calculating total magma storage. For example, during the 2012 unrest period at Santorini volcano, approximately 0.021 km3 of new magma entered a shallow chamber residing at around 4 km below the surface. This type of event is not unusual, and is in fact a necessary condition for the formation of a long-lived shallow chamber. The period of unrest ended without culminating in eruption, i.e the amount of magma which entered the chamber was insufficient to break the chamber and force magma further towards the surface. Using continuum-mechanics and fracture-mechanics principles, we present a model to calculate the amount of magma contained at shallow depth beneath active volcanoes. Here we discuss our model in the context of Santorini volcano, Greece. We demonstrate through structural analysis of dykes exposed within the Santorini caldera, previously published data on the volume of recent eruptions, and geodetic measurements of the 2011-2012 unrest period, that the measured 0.02% increase in volume of Santorini's shallow magma chamber was associated with magmatic excess pressure increase of around 1.1 MPa. This excess pressure was high enough to bring the chamber roof close to rupture and dyke injection. For volcanoes with known typical extrusion and intrusion (dyke) volumes, the new methodology presented here makes it possible to forecast the conditions for magma-chamber failure and dyke injection at any geodetically well-monitored volcano.

  1. Robust Acoustic Transducers for Bubble Chambers

    NASA Astrophysics Data System (ADS)

    Wells, Jonathan

    2015-04-01

    The PICO collaboration utilizes bubble chambers filled with various superheated liquids as targets for dark matter. Acoustic sensors have proved able to distinguish nuclear recoils from radioactive background on an event-by-event basis. We have recently produced a more robust transducer which should be able to operate for years, rather than months, in the challenging environment of a heated high pressure hydraulic fluid outside these chambers. Indiana University South Bend.

  2. How does a bubble chamber work?

    SciTech Connect

    Konstantinov, D.; Homsi, W.; Luzuriaga, J.; Su, C.K.; Weilert, M.A.; Maris, H.J.

    1998-11-01

    A charged particle passing through a bubble chamber produces a track of bubbles. The way in which these bubbles are produced has been a matter of some controversy. The authors consider the possibility that in helium and hydrogen bubble chambers the production of bubbles is primarily a mechanical process, rather than a thermal process as has often been assumed. The model the authors propose gives results which are in excellent agreement with experiment.

  3. Engine Knock and Combustion Chamber Form

    NASA Technical Reports Server (NTRS)

    Zinner, Karl

    1939-01-01

    The present report is confined to the effect of the combustion chamber shape on engine knock from three angles, namely: 1) The uniformity of flame-front movement as affected by chamber design and position of the spark plug; 2) The speed of advance of the flame as affected by turbulence and vibrations; 3) The reaction processes in the residual charge as affected by the walls.

  4. Tracking with wire chambers at high luminosities

    SciTech Connect

    Hanson, G.G. Stanford Linear Accelerator Center, Menlo Park, CA )

    1989-12-01

    Radiation damage and rate limitations impose severe constraints on wire chambers at the SSC. Possible conceptual designs for wire chamber tracking systems that satisfy these constraints are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 11 refs., 10 figs.

  5. 40 CFR 792.45 - Test system supply facilities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... maintaining algae and aquatic plants. (2) Facilities, as specified in the protocol, for plant growth, including but not limited to, greenhouses, growth chambers, light banks, and fields. (c) When appropriate... supplies shall be preserved by appropriate means. (b) When appropriate, plant supply facilities shall...

  6. 40 CFR 792.45 - Test system supply facilities.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... maintaining algae and aquatic plants. (2) Facilities, as specified in the protocol, for plant growth, including but not limited to, greenhouses, growth chambers, light banks, and fields. (c) When appropriate... supplies shall be preserved by appropriate means. (b) When appropriate, plant supply facilities shall...

  7. 40 CFR 792.45 - Test system supply facilities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... maintaining algae and aquatic plants. (2) Facilities, as specified in the protocol, for plant growth, including but not limited to, greenhouses, growth chambers, light banks, and fields. (c) When appropriate... supplies shall be preserved by appropriate means. (b) When appropriate, plant supply facilities shall...

  8. 40 CFR 792.45 - Test system supply facilities.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... maintaining algae and aquatic plants. (2) Facilities, as specified in the protocol, for plant growth, including but not limited to, greenhouses, growth chambers, light banks, and fields. (c) When appropriate... supplies shall be preserved by appropriate means. (b) When appropriate, plant supply facilities shall...

  9. The GODDESS ionization chamber: developing robust windows

    NASA Astrophysics Data System (ADS)

    Blanchard, Rose; Baugher, Travis; Cizewski, Jolie; Pain, Steven; Ratkiewicz, Andrew; Goddess Collaboration

    2015-10-01

    Reaction studies of nuclei far from stability require high-efficiency arrays of detectors and the ability to identify beam-like particles, especially when the beam is a cocktail beam. The Gammasphere ORRUBA Dual Detectors for Experimental Structure Studies (GODDESS) is made up of the Oak Ridge-Rutgers University Barrel Array (ORRUBA) of silicon detectors for charged particles inside of the gamma-ray detector array Gammasphere. A high-rate ionization chamber is being developed to identify beam-like particles. Consisting of twenty-one alternating anode and cathode grids, the ionization chamber sits downstream of the target chamber and is used to measure the energy loss of recoiling ions. A critical component of the system is a thin and robust mylar window which serves to separate the gas-filled ionization chamber from the vacuum of the target chamber with minimal energy loss. After construction, windows were tested to assure that they would not break below the required pressure, causing harm to the wire grids. This presentation will summarize the status of the ionization chamber and the results of the first tests with beams. This work is supported in part by the U.S. Department of Energy and National Science Foundation.

  10. Upright Imaging of Drosophila Egg Chambers

    PubMed Central

    Manning, Lathiena; Starz-Gaiano, Michelle

    2015-01-01

    Drosophila melanogaster oogenesis provides an ideal context for studying varied developmental processes since the ovary is relatively simple in architecture, is well-characterized, and is amenable to genetic analysis. Each egg chamber consists of germ-line cells surrounded by a single epithelial layer of somatic follicle cells. Subsets of follicle cells undergo differentiation during specific stages to become several different cell types. Standard techniques primarily allow for a lateral view of egg chambers, and therefore a limited view of follicle cell organization and identity. The upright imaging protocol describes a mounting technique that enables a novel, vertical view of egg chambers with a standard confocal microscope. Samples are first mounted between two layers of glycerin jelly in a lateral (horizontal) position on a glass microscope slide. The jelly with encased egg chambers is then cut into blocks, transferred to a coverslip, and flipped to position egg chambers upright. Mounted egg chambers can be imaged on either an upright or an inverted confocal microscope. This technique enables the study of follicle cell specification, organization, molecular markers, and egg development with new detail and from a new perspective. PMID:25867882

  11. Development of sputtered techniques for thrust chambers

    NASA Technical Reports Server (NTRS)

    Mullaly, J. R.; Hecht, R. J.; Schmid, T. E.; Torrey, C. T.

    1975-01-01

    Techniques and materials were developed and evaluated for the fabrication and coating of advanced, long life, regeneratively cooled thrust chambers. Materials were analyzed as fillers for sputter application of OFHC copper as a closeout layer to channeled inner structures; of the materials evaluated, aluminum was found to provide the highest bond strength and to be the most desirable for chamber fabrication. The structures and properties were investigated of thick sputtered OFHC copper, 0.15 Zr-Cu, Al2O3,-Cu, and SiC-Cu. Layered structures of OFHC copper and 0.15 Zr-Cu were investigated as means of improving chamber inner wall fatigue life. The evaluation of sputtered Ti-5Al-2.5Sn, NASA IIb-11, aluminum and Al2O3-Al alloys as high strength chamber outer jackets was performed. Techniques for refurbishing degraded thrust chambers with OFHC copper and coating thrust chambers with protective ZrO2 and graded ZrO2-copper thermal barrier coatings were developed.

  12. Chamber for Growing and Observing Fungi

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Molina, Thomas C.

    2005-01-01

    A chamber has been designed to enable growth and observation of microcolonies of fungi in isolation from the external environment. Unlike prior fungus-growing apparatuses, this chamber makes it possible to examine a fungus culture without disrupting it. Partly resembling a small picture frame, the chamber includes a metal plate having a rectangular through-thethickness opening with recesses for a top and a bottom cover glass, an inlet for air, and an inlet for water. The bottom cover glass is put in place and held there by clips, then a block of nutrient medium and a moisture pad are placed in the opening. The block is inoculated, then the top cover glass is put in place and held there by clips. Once growth is evident, the chamber can be sealed with tape. Little (if any) water evaporates past the edges of the cover glasses, and, hence there is little (if any) need to add water. A microscope can be used to observe the culture through either cover glass. Because the culture is sealed in the chamber, it is safe to examine the culture without risking contamination. The chamber can be sterilized and reused.

  13. Designing an Active Target Test Projection Chamber

    NASA Astrophysics Data System (ADS)

    Koci, James; Tan Ahn Collaboration, Dr.; Nicolas Dixneuf Collaboration

    2015-10-01

    The development of instrumentation in nuclear physics is crucial for advancing our ability to measure the properties of exotic nuclei. One limitation of the use of exotic nuclei in experiment is their very low production intensities. Recently, detectors, called active-target dectectors, have been developed to address this issue. Active-target detectors use a gas medium to image charged-particle tracks that are emitted in nuclear reactions. Last semester, I designed a vacuum chamber to be used in developing Micro-Pattern Gas detectors that will upgrade the capabilities of an active-target detector called the Prototype AT-TPC. With the exterior of the chamber complete, I have now been using an electric field modeling program, Garfield, developed by CERN to design a field cage to be placed within the vacuum chamber. The field cage will be a box-like apparatus consisting of two parallel metal plates connected with a resistor chain and attached to wires wrapped between them. The cage will provide a uniform electric field within the chamber to drift electrons from nuclear reactions down to the detector in the bottom of the chamber. These signals are then amplified by a proportional counter, and the data is sent to a computer. For the long term, we would like to incorporate a Micro-Pattern Gas Detectors in the interior of the chamber and eventually use the AT-TPC to examine various nuclei. Dr. Ahn is my advising professor.

  14. Expandable Purge Chambers Would Protect Cryogenic Fittings

    NASA Technical Reports Server (NTRS)

    Townsend, Ivan I., III

    2004-01-01

    Expandable ice-prevention and cleanliness-preservation (EIP-CP) chambers have been proposed to prevent the accumulation of ice or airborne particles on quick-disconnect (QD) fittings, or on ducts or tubes that contain cryogenic fluids. In the original application for which the EIP-CP chambers were conceived, there is a requirement to be able to disconnect and reconnect the QD fittings in rapid succession. If ice were to form on the fittings by condensation and freezing of airborne water vapor on the cold fitting surfaces, the ice could interfere with proper mating of the fittings, making it necessary to wait an unacceptably long time for the ice to thaw before attempting reconnection. By keeping water vapor away from the cold fitting surfaces, the EIP-CP chambers would prevent accumulation of ice, preserving the ability to reconnect as soon as required. Basically, the role of an EIP-CP chamber would be to serve as an enclosure for a flow of dry nitrogen gas that would keep ambient air away from QD cryogenic fittings. An EIP-CP chamber would be an inflatable device made of a fabriclike material. The chamber would be attached to an umbilical plate holding a cryogenic QD fitting.

  15. The PEP Quark Search Proportional Chambers

    NASA Astrophysics Data System (ADS)

    Parker, S. I.; Harris, F.; Karliner, I.; Yount, D.; Ely, R.; Hamilton, R.; Pun, T.; Guryn, W.; Miller, D.; Fries, R.

    1981-04-01

    Proportional chambers are used in the PEP Free Quark Search to identify and remove possible background sources such as particles traversing the edges of counters, to permit geometric corrections to the dE/dx and TOF information from the scintillator and Cerenkov counters, and to look for possible high cross section quarks. The present beam pipe has a thickness of 0.007 interaction lengths (λi) and is followed in both arms (each with 45° <= θ <= 135°. Δphi = 90°) by 5 proportional chambers, each 0.0008 λi thick with 32 channels of pulse height readout, and by 3 thin scintillator planes, each 0.003 λi thick. Following this thin front end, each arm of the detector has 8 layers of scintillator (one with scintillating light pipes) interspersed with 4 proportional chambers and a layer of lucite Cerenkov counters. Both the calculated ion statistics and measurements using He-CH4 gas in a test chamber indicate that the chamber efficiencies should be > 98% for q = 1/3. The Landau spread measured in the test was equal to that observed for normal q = 1 traversals. One scintillator plane and thin chamber in each arm will have an extra set of ADC's with a wide gate bracketing the normal one so timing errors and tails of earlier pulses should not produce fake quarks.

  16. Upright imaging of Drosophila egg chambers.

    PubMed

    Manning, Lathiena; Starz-Gaiano, Michelle

    2015-03-13

    Drosophila melanogaster oogenesis provides an ideal context for studying varied developmental processes since the ovary is relatively simple in architecture, is well-characterized, and is amenable to genetic analysis. Each egg chamber consists of germ-line cells surrounded by a single epithelial layer of somatic follicle cells. Subsets of follicle cells undergo differentiation during specific stages to become several different cell types. Standard techniques primarily allow for a lateral view of egg chambers, and therefore a limited view of follicle cell organization and identity. The upright imaging protocol describes a mounting technique that enables a novel, vertical view of egg chambers with a standard confocal microscope. Samples are first mounted between two layers of glycerin jelly in a lateral (horizontal) position on a glass microscope slide. The jelly with encased egg chambers is then cut into blocks, transferred to a coverslip, and flipped to position egg chambers upright. Mounted egg chambers can be imaged on either an upright or an inverted confocal microscope. This technique enables the study of follicle cell specification, organization, molecular markers, and egg development with new detail and from a new perspective.

  17. Cyclic fatigue analysis of rocket thrust chambers. Volume 1: OFHC copper chamber low cycle fatigue

    NASA Technical Reports Server (NTRS)

    Miller, R. W.

    1974-01-01

    A three-dimensional finite element elasto-plastic strain analysis was performed for the throat section of a regeneratively cooled rocket combustion chamber. The analysis employed the RETSCP finite element computer program. The analysis included thermal and pressure loads, and the effects of temperature dependent material properties, to determine the strain range corresponding to the chamber operating cycle. The analysis was performed for chamber configuration and operating conditions corresponding to a hydrogen-oxygen combustion chamber which was fatigue tested to failure. The computed strain range at typical chamber operating conditions was used in conjunction with oxygen-free, high-conductivity (OHFC) copper isothermal fatigue test data to predict chamber low-cycle fatigue life.

  18. 12. View north of Tropic Chamber. Natick Research & ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. View north of Tropic Chamber. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  19. 13. View south of Arctic Chamber. Natick Research & ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. View south of Arctic Chamber. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  20. RADIATION FACILITY FOR NUCLEAR REACTORS

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1961-12-12

    A radiation facility is designed for irradiating samples in close proximity to the core of a nuclear reactor. The facility comprises essentially a tubular member extending through the biological shield of the reactor and containing a manipulatable rod having the sample carrier at its inner end, the carrier being longitudinally movable from a position in close proximity to the reactor core to a position between the inner and outer faces of the shield. Shield plugs are provided within the tubular member to prevent direct radiation from the core emanating therethrough. In this device, samples may be inserted or removed during normal operation of the reactor without exposing personnel to direct radiation from the reactor core. A storage chamber is also provided within the radiation facility to contain an irradiated sample during the period of time required to reduce the radioactivity enough to permit removal of the sample for external handling. (AEC)

  1. Temperature dependent BRDF facility

    NASA Astrophysics Data System (ADS)

    Airola, Marc B.; Brown, Andrea M.; Hahn, Daniel V.; Thomas, Michael E.; Congdon, Elizabeth A.; Mehoke, Douglas S.

    2014-09-01

    Applications involving space based instrumentation and aerodynamically heated surfaces often require knowledge of the bi-directional reflectance distribution function (BRDF) of an exposed surface at high temperature. Addressing this need, the Johns Hopkins University Applied Physics Laboratory (JHU/APL) developed a BRDF facility that features a multiple-port vacuum chamber, multiple laser sources covering the spectral range from the longwave infrared to the ultraviolet, imaging pyrometry and laser heated samples. Laser heating eliminates stray light that would otherwise be seen from a furnace and requires minimal sample support structure, allowing low thermal conduction loss to be obtained, which is especially important at high temperatures. The goal is to measure the BRDF of ceramic-coated surfaces at temperatures in excess of 1000°C in a low background environment. Most ceramic samples are near blackbody in the longwave infrared, thus pyrometry using a LWIR camera can be very effective and accurate.

  2. [Characterization of photochemical smog chamber and initial experiments].

    PubMed

    Jia, Long; Xu, Yong-Fu; Shi, Yu-Zhen

    2011-02-01

    A self-made new indoor environmental chamber facility for the study of atmospheric processes leading to the formation of ozone and secondary organic aerosols has been introduced and characterized. The characterization experiments include the measurements of wall effects for reactive species and the determination of chamber dependent * OH radical sources by CO-NO(x) irradiation experiments. Preliminary ethene-NO(x) and benzene-NO(x) experiments were conducted as well. The results of characterization experiments show that the wall effects for O3 and NO2 in a new reactor are not obvious. Relative humidity has a great effect on the wall losses in the old reactor, especially for O3. In the old reactor, the rate constant for O3 wall losses is obtained to be 1.0 x 10(-5) s(-1) (RH = 5%) and 4.0 x10(-5) s(-1) (RH = 91%), whereas for NO2, it is 1.0 x 10(-6) s(-1) (RH = 5%) and 0.6 x 10(-6) s(-1) (RH = 75%). The value for k(NO2 --> HONO) determined by CO-NO(x) irradiation experiments is (4.2-5.2) x 10(-5) s(-1) and (2.3-2.5) x 10(-5) s(-1) at RH = 5% and RH 75% -77%, respectively. The average *OH concentration is estimated to be (2.1 +/- 0.4) x 10(6) molecules/cm3 by using a reaction rate coefficient of CO and * OH. The sensitivity of chamber dependent auxiliary reactions to the O3 formation is discussed. Results show that NO2 --> HONO has the greatest impact on the O3 formation during the initial stage, N2O5 + H2O --> 2HNO3 has a minus effect to maximum O3 concentration, and that the wall losses of both O3 and NO2 have little impact on the O3 formation. The results from the ethene-NO(x) and benzene-NO(x) experiments are in good agreement with those from the MCM simulation, which reflects that the facility for the study of the formation of secondary pollution of ozone and secondary organic aerosols is reliable. This demonstrates that our facility can be further used in the deep-going study of chemical processes in the atmosphere.

  3. SRMAFTE facility checkout model flow field analysis

    NASA Technical Reports Server (NTRS)

    Dill, Richard A.; Whitesides, Harold R.

    1992-01-01

    The Solid Rocket Motor Air Flow Equipment (SRMAFTE) facility was constructed for the purpose of evaluating the internal propellant, insulation, and nozzle configurations of solid propellant rocket motor designs. This makes the characterization of the facility internal flow field very important in assuring that no facility induced flow field features exist which would corrupt the model related measurements. In order to verify the design and operation of the facility, a three-dimensional computational flow field analysis was performed on the facility checkout model setup. The checkout model measurement data, one-dimensional and three-dimensional estimates were compared, and the design and proper operation of the facility was verified. The proper operation of the metering nozzles, adapter chamber transition, model nozzle, and diffuser were verified. The one-dimensional and three-dimensional flow field estimates along with the available measurement data are compared.

  4. TRIDENT high-energy-density facility experimental capabilities and diagnostics.

    PubMed

    Batha, S H; Aragonez, R; Archuleta, F L; Archuleta, T N; Benage, J F; Cobble, J A; Cowan, J S; Fatherley, V E; Flippo, K A; Gautier, D C; Gonzales, R P; Greenfield, S R; Hegelich, B M; Hurry, T R; Johnson, R P; Kline, J L; Letzring, S A; Loomis, E N; Lopez, F E; Luo, S N; Montgomery, D S; Oertel, J A; Paisley, D L; Reid, S M; Sanchez, P G; Seifter, A; Shimada, T; Workman, J B

    2008-10-01

    The newly upgraded TRIDENT high-energy-density (HED) facility provides high-energy short-pulse laser-matter interactions with powers in excess of 200 TW and energies greater than 120 J. In addition, TRIDENT retains two long-pulse (nanoseconds to microseconds) beams that are available for simultaneous use in either the same experiment or a separate one. The facility's flexibility is enhanced by the presence of two separate target chambers with a third undergoing commissioning. This capability allows the experimental configuration to be optimized by choosing the chamber with the most advantageous geometry and features. The TRIDENT facility also provides a wide range of standard instruments including optical, x-ray, and particle diagnostics. In addition, one chamber has a 10 in. manipulator allowing OMEGA and National Ignition Facility (NIF) diagnostics to be prototyped and calibrated.

  5. TRIDENT high-energy-density facility experimental capabilities and diagnosticsa)

    NASA Astrophysics Data System (ADS)

    Batha, S. H.; Aragonez, R.; Archuleta, F. L.; Archuleta, T. N.; Benage, J. F.; Cobble, J. A.; Cowan, J. S.; Fatherley, V. E.; Flippo, K. A.; Gautier, D. C.; Gonzales, R. P.; Greenfield, S. R.; Hegelich, B. M.; Hurry, T. R.; Johnson, R. P.; Kline, J. L.; Letzring, S. A.; Loomis, E. N.; Lopez, F. E.; Luo, S. N.; Montgomery, D. S.; Oertel, J. A.; Paisley, D. L.; Reid, S. M.; Sanchez, P. G.; Seifter, A.; Shimada, T.; Workman, J. B.

    2008-10-01

    The newly upgraded TRIDENT high-energy-density (HED) facility provides high-energy short-pulse laser-matter interactions with powers in excess of 200TW and energies greater than 120J. In addition, TRIDENT retains two long-pulse (nanoseconds to microseconds) beams that are available for simultaneous use in either the same experiment or a separate one. The facility's flexibility is enhanced by the presence of two separate target chambers with a third undergoing commissioning. This capability allows the experimental configuration to be optimized by choosing the chamber with the most advantageous geometry and features. The TRIDENT facility also provides a wide range of standard instruments including optical, x-ray, and particle diagnostics. In addition, one chamber has a 10in. manipulator allowing OMEGA and National Ignition Facility (NIF) diagnostics to be prototyped and calibrated.

  6. Neutron imaging with bubble chambers for inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Ghilea, Marian C.

    One of the main methods to obtain energy from controlled thermonuclear fusion is inertial confinement fusion (ICF), a process where nuclear fusion reactions are initiated by heating and compressing a fuel target, typically in the form of a pellet that contains deuterium and tritium, relying on the inertia of the fuel mass to provide confinement. In inertial confinement fusion experiments, it is important to distinguish failure mechanisms of the imploding capsule and unambiguously diagnose compression and hot spot formation in the fuel. Neutron imaging provides such a technique and bubble chambers are capable of generating higher resolution images than other types of neutron detectors. This thesis explores the use of a liquid bubble chamber to record high yield 14.1 MeV neutrons resulting from deuterium-tritium fusion reactions on ICF experiments. A design tool to deconvolve and reconstruct penumbral and pinhole neutron images was created, using an original ray tracing concept to simulate the neutron images. The design tool proved that misalignment and aperture fabrication errors can significantly decrease the resolution of the reconstructed neutron image. A theoretical model to describe the mechanism of bubble formation was developed. A bubble chamber for neutron imaging with Freon 115 as active medium was designed and implemented for the OMEGA laser system. High neutron yields resulting from deuterium-tritium capsule implosions were recorded. The bubble density was too low for neutron imaging on OMEGA but agreed with the model of bubble formation. The research done in here shows that bubble detectors are a promising technology for the higher neutron yields expected at National Ignition Facility (NIF).

  7. Operations on the National Ignition Facility

    DOE PAGESBeta

    Brereton, Sandra J.; Burr, Robert F.; Folta, Peg; Keane, Christopher J.; Kohut, Thomas R.; Merritt, Bernard T.; Van Wonterghem, Bruno M.

    2014-03-24

    The National Ignition Facility (NIF) is a fully operational high energy density physics experimental user facility that focuses 192 laser beams onto a small target at the center of a target chamber. This paper describes how we execute experimental shots on the NIF, both from the user perspective and from the facility perspective. We review the planning processes and tools used to facilitate operations. Safety and radiological aspects of NIF’s operations are discussed. We also describe efforts to continuously improve operations and further increase shot rate.

  8. Calibration of IR test chambers with the missile defense transfer radiometer

    NASA Astrophysics Data System (ADS)

    Kaplan, Simon G.; Woods, Solomon I.; Carter, Adriaan C.; Jung, Timothy M.

    2013-05-01

    The Missile Defense Transfer Radiometer (MDXR) is designed to calibrate infrared collimated and flood sources over the fW/cm2 to W/cm2 power range from 3 μm to 28μ m in wavelength. The MDXR operates in three different modes: as a filter radiometer, a Fourier-transform spectrometer (FTS)-based spectroradiometer, and as an absolute cryogenic radiometer (ACR). Since 2010, the MDXR has made measurements of the collimated infrared irradiance at the output port of seven different infrared test chambers at several facilities. We present a selection of results from these calibration efforts compared to signal predictions from the respective chamber models for the three different MDXR calibration modes. We also compare the results to previous measurements made of the same chambers with a legacy transfer radiometer, the NIST BXR. In general, the results are found to agree within their combined uncertainties, with the MDXR having 30 % lower uncertainty and greater spectral coverage.

  9. Stability of A-150 plastic ionization chamber response over a ~30 year period

    SciTech Connect

    Kroc, Thomas K.; Lennox, Arlene J.; /Fermilab

    2007-08-01

    At the NIU Institute for Neutron Therapy at Fermilab, the clinical tissue-equivalent ionization chamber response is measured every treatment day using a cesium source that was configured to match readings obtained at the National Bureau of Standards. Daily measurements are performed in air using the air-to-tissue dose conversion factors given in AAPM Report no. 7. The measured exposure calibration factors have been tabulated and graphed as a function of time from 1978 to present. For A-150 plastic ionization chambers, these factors exhibit a sinusoidal variation with a period of approximately one year and amplitude of {+-} 1%. This variation, attributable to the hygroscopic nature of A-150 plastic, is correlated with the relative humidity of the facility, and is greater than the humidity corrections for gas described in the literature. Our data suggest that chamber calibration should be performed at least weekly to accommodate these variations.

  10. Motor Controls for the NIFFTE Time Projection Chamber Positioning Stand

    NASA Astrophysics Data System (ADS)

    Pamplin, Daniel; Pickle, Nathan

    2010-11-01

    The next generation nuclear power plants will be more efficient and produce smaller amounts of radioactive waste. Design of these new reactors is limited partially by the lack of precise neutron induced fission cross sections at certain incident neutron energies of several isotopes. In order to reduce the uncertainty of the cross sections to less than 1 percent, a Time Projection Chamber (TPC) was built by the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration. These improvements in precision will be possible due to the TPC's ability for a full 3-D reconstruction of the fission fragment tracks. The NIFFTE TPC will be installed at Los Alamos National Lab's LANSCE facility. Thin targets will be mounted in the center of the TPC in a pressurized hydrogen gas chamber so that both hemispheres of the reaction will be covered. In this work we will discuss the control of the stepper motors that drive the positioning table of the TPC, which has all of its readout electronics attached, to be lined up with the beam. This includes both the controlling software and its graphical interface to the MIDAS online data acquisition system.

  11. Motor Controls for the NIFFTE Time Projection Chamber Positioning Stand

    NASA Astrophysics Data System (ADS)

    Pamplin, Daniel; Pickle, Nathan

    2010-10-01

    The next generation nuclear power plants will be more efficient and produce smaller amounts of radioactive waste. Design of these new reactors is limited partially by the lack of precise neutron induced fission cross sections at certain incident neutron energies of several isotopes. In order to reduce the uncertainty of the cross sections to less than 1%, a Time Projection Chamber (TPC) was built by the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration. These improvements in precision will be possible due to the TPC's ability for a full 3-D reconstruction of the fission fragment tracks. The NIFFTE TPC will be installed at Los Alamos National Lab's LANSCE facility. Thin targets will be mounted in the center of the TPC in a pressurized hydrogen gas chamber so that both hemispheres of the reaction will be covered. This talk considers the control of the stepper motors that drive the positioning table of the TPC, which has all of its readout electronics attached, to be lined up with the beam. This includes both the controlling software and its graphical interface to the MIDAS online data acquisition system.

  12. Development of the Position Sensitive Ionization Chamber for ANASEN

    NASA Astrophysics Data System (ADS)

    Gardiner, Hannah; Blackmon, Jeff; Deibel, Catherine; Gardiner, Emily; Lai, Jianping; Lauer, Amber; Linhardt, Laura; Macon, Kevin; Rasco, Charlie; Baby, Lagy; Koshchiy, Yevegn; Rogachev, Grigory; Santiago-Gonzales, Daniel; Wiedenhoever, Ingo; Bardayan, Dan; Matos, Milan

    2013-10-01

    The Array for Nuclear Astrophysics Studies with Exotic Nuclei (ANASEN) is a charged-particle detector array developed for reaction studies using radioactive ion beams to help improve understanding of the nuclear reactions important in stellar explosions. A gas-filled ionization chamber with two position-sensitive anode wire grid planes read out in 32 channels, and 12 alternating anode/cathode planes was developed and tested for use with ANASEN to identify the kinematic trajectory and atomic number of recoiling heavy ions by their relative energy loss. The position sensitive grids are arranged perpendicularly to each other in order to determine the x-y position of each ion with better than 4 mm resolution. This ionization chamber was tested using a stable beam of 12C at FSU. We report on the performance of this test experiment and plans for measurements with radioactive ion beams at FSU. Two other versions of the detector have been constructed and are now in place at the National Superconducting Cyclotron Laboratory and at the ATLAS accelerator facility at Argonne National Laboratory.

  13. Focal Point Inside the Vacuum Chamber for Solar Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated, and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. The 20- by 24-ft heliostat mirror (not shown in this photograph) has dual-axis control that keeps a reflection of the sunlight on an 18-ft diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. This photograph is a close-up view of a 4-in focal point inside the vacuum chamber at the MSFC Solar Thermal Propulsion Test facility. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move the Nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth orbit, rapid travel throughout the solar system, and exploration of interstellar space.

  14. Comments on settling chamber design for quiet, blowdown wind tunnels

    NASA Technical Reports Server (NTRS)

    Beckwith, I. E.

    1981-01-01

    Transfer of an existing continous circuit supersonic wind tunnel to Langley and its operation there as a blowdown tunnel is planned. Flow disturbance requirements in the supply section and methods for reducing the high level broad band acoustic disturbances present in typical blowdown tunnels are reviewed. Based on recent data and the analysis of two blowdown facilities at Langley, methods for reducing the total turbulence levels in the settling chamber, including both acoustic and vorticity modes, to less than one percent are recommended. The pertinent design details of the damping screens and honeycomb and the recommended minimum pressure drop across the porous components providing the required two orders of magnitude attenuation of acoustic noise levels are given. A suggestion for the support structure of these high pressure drop porous components is offered.

  15. Team Huddle Before Lifting Phoenix into Test Chamber

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Spacecraft specialists huddle to discuss the critical lift of NASA's Phoenix Mars Lander into a thermal vacuum chamber.

    In December 2006, the spacecraft was in a cruise configuration prior to going into environmental testing at a Lockheed Martin Space Systems facility near Denver. At all stages of assembly and testing, the spacecraft is handled with extreme care and refinement.

    The Phoenix mission is led by Principal Investigator Peter H. Smith of the University of Arizona, Tucson, with project management at NASA's Jet Propulsion Laboratory and development partnership with Lockheed Martin Space Systems. International contributions for Phoenix are provided by the Canadian Space Agency, the University of Neuchatel (Switzerland), the University of Copenhagen, and the Max Planck Institute in Germany. JPL is a division of the California Institute of Technology in Pasadena.

  16. Design characteristics of a heat pipe test chamber

    NASA Technical Reports Server (NTRS)

    Baker, Karl W.; Jang, J. Hoon; Yu, Juin S.

    1992-01-01

    LeRC has designed a heat pipe test facility which will be used to provide data for validating heat pipe computer codes. A heat pipe test chamber that uses helium gas for enhancing heat transfer was investigated. The conceptual design employs the technique of guarded heating and guarded cooling to facilitate accurate measurements of heat transfer rates to the evaporator and from the condenser. The design parameters are selected for a baseline heat pipe made of stainless steel with an inner diameter of 38.10 mm and a wall thickness of 1.016 mm. The heat pipe operates at a design temperature of 1000 K with an evaporator radial heat flux of 53 W/sq. cm.

  17. Tuned Chamber Core Panel Acoustic Test Results

    NASA Technical Reports Server (NTRS)

    Schiller, Noah H.; Allen, Albert R.

    2016-01-01

    This report documents acoustic testing of tuned chamber core panels, which can be used to supplement the low-frequency performance of conventional acoustic treatment. The tuned chamber core concept incorporates low-frequency noise control directly within the primary structure and is applicable to sandwich constructions with a directional core, including corrugated-, truss-, and fluted-core designs. These types of sandwich structures have long, hollow channels (or chambers) in the core. By adding small holes through one of the facesheets, the hollow chambers can be utilized as an array of low-frequency acoustic resonators. These resonators can then be used to attenuate low-frequency noise (below 400 Hz) inside a vehicle compartment without increasing the weight or size of the structure. The results of this test program demonstrate that the tuned chamber core concept is effective when used in isolation or combined with acoustic foam treatments. Specifically, an array of acoustic resonators integrated within the core of the panels was shown to improve both the low-frequency absorption and transmission loss of the structure in targeted one-third octave bands.

  18. [Inhospital thrombolism of right cardiac chambers].

    PubMed

    Vasil'tseva, O Ia; Vorozhtsova, I N; Karpov, R S

    2013-01-01

    Veins of lower extremities are classic sources of pulmonary artery thromboembolism (PATE). But one should not underestimate presence of thrombi in other potential sources - veins of small pelvis, superior vena cava, and chambers of the heart. We analyzed 652 case histories and autopsy data of patients in whom PATE had been revealed at pathological anatomical investigation and selected 157 cases in which right heart chambers were sources of emboli (right atrium in 83.5% and right ventricle - in 13.7% of cases). According to autopsy data average mass of the heart was 512.5+/-36.1 g. In most patients it exceeded norm. Thrombi in both right and left cardiac chambers were found in 52.3% of cases. Eighty three patients had history of myocardial infarction or were treated for MI during last hospitalization; 52.3% of patients had atrial fibrillation. After detailed study of all anamnestic, clinical, instrumental, and pathologic-anatomic data we selected 69 factors which according to contemporary views could facilitate formation of thrombus in the right cardiac chambers. Using these factors and method of logistic regression we created a mathematical model for assessment of probability of the presence of thrombi in right cardiac chambers.

  19. Chamber, Target and Final Focus Integrated Design

    SciTech Connect

    Moir, R.W

    2000-03-22

    Liquid wall protection, which challenges chamber clearing, has such advantages it's Heavy Ion Fusion's (HIF) main line chamber design. Thin liquid protection from x rays is necessary to avoid erosion of structural surfaces and thick liquid makes structures behind 0.5 m of Flibe (7 mean free paths for 14 MeV neutrons), last the life of the plant. Liquid wall protection holds the promise of greatly increased economic competitiveness. Driver designers require {approx}200 beams to illuminate recent target designs from two sides. The illumination must be compatible with liquid wall protection. The ''best'' values for driver energy, gain, yield and pulse rate comes out of well-known trade-off studies. An integrated chamber design, yet to be made, depends on several key assumptions, which are to be proven before HIF can be shown to be feasible. The chamber R&D needed to reduce the unknowns and risks depend on resolving a few technical issues such as jet surface smoothness and rapid chamber clearing.

  20. Chamber, Target and Final Focus Integrated Design

    SciTech Connect

    Moir, R.W.

    2000-03-03

    Liquid wall protection, which challenges chamber clearing, has such advantages it's Heavy Ion Fusion's (HIF) main line chamber design. Thin liquid protection from x rays is necessary to avoid erosion of structural surfaces and thick liquid makes structures behind 0.5 m of Flibe (7 mean free paths for 14 MeV neutrons), last the life of the plant. Liquid wall protection holds the promise of greatly increased economic competitiveness. Driver designers require {approx}200 beams to illuminate recent target designs from two sides. The illumination must be compatible with liquid wall protection. The ''best'' values for driver energy, gain, yield and pulse rate comes out of well-known trade-off studies. The chamber design is based on several key assumptions, which are to be proven before HIF can be shown to be feasible. The chamber R&D needed to reduce the unknowns and risks depend on resolving a few technical issues such as jet surface smoothness and rapid chamber clearing.

  1. Aging effect in the BESIII drift chamber

    NASA Astrophysics Data System (ADS)

    Dong, Ming-Yi; Xiu, Qing-Lei; Wu, Ling-Hui; Wu, Zhi; Qin, Zhong-Hua; Shen, Pin; An, Fen-Fen; Ju, Xu-Dong; Liu, Yi; Zhu, Kai; Qun, Ou-Yang; Chen, Yuan-Bo

    2016-01-01

    As the main tracking detector of BESIII, the drift chamber provides accurate measurements of the position and the momentum of the charged particles produced in e+e- collisions at BEPCII. After six years of operation, the drift chamber is suffering from aging problems due to huge beam-related background. The gains of the cells in the first ten layers show an obvious decrease, reaching a maximum decrease of about 29% for the first layer cells. Two calculation methods for the gain change (Bhabha events and accumulated charges with 0.3% aging ratio for inner chamber cells) give almost the same results. For the Malter effect encountered by the inner drift chamber in January 2012, about 0.2% water vapor was added to the MDC gas mixture to solve this cathode aging problem. These results provide an important reference for MDC operating high voltage settings and the upgrade of the inner drift chamber. Supported by the CAS Center for Excellence in Particle Physics (CCEPP)

  2. Facility Planning.

    ERIC Educational Resources Information Center

    Graves, Ben E.

    1984-01-01

    This article reviews recommendations on policies for leasing surplus school space made during the Council of Educational Facility Planners/International conference. A case study presentation of a Seattle district's use of lease agreements is summarized. (MJL)

  3. Health Facilities

    MedlinePlus

    Health facilities are places that provide health care. They include hospitals, clinics, outpatient care centers, and specialized care centers, such as birthing centers and psychiatric care centers. When you ...

  4. Production facilities

    SciTech Connect

    Not Available

    1989-01-01

    This book presents a cross section of different solutions to the many unique production problems operators face. Sections address benefit vs. cost options for production facility designs, oil and gas separation processes and equipment, oil treating and desalting systems, and water treating methods and equipment. Papers were selected to give an overall view of factors involved in optimizing the design of cost-effective production facilities.

  5. Final report for NIF chamber dynamics studies, final rept (May 1997), Subcontract No. B291847

    SciTech Connect

    Peterson, P.F.; Jin, H.; Scott, J.M.

    1997-07-01

    The National Ignition Facility (NIF), a 1.8 MJ, 192 laser beam facility, will have anticipated fusion yields of up to 20 MJ from D-T pellets encased in a gold hohlraum target. The energy emitted from the target in the form of x rays, neutrons, target debris kinetic energy, and target shrapnel will be contained in a 5 m. radius spherical target chamber. Various diagnostics will be stationed around the target at varying distances from the target. During each shot, the target will emit x rays that will vaporize nearby target facing surfaces including those of the diagnostics, the target positioner, and other chamber structures. This ablated vapor will be transported throughout the chamber, and will eventually condense and deposit on surfaces in the chamber, including the final optics debris shields. The research at the University of California at Berkeley relates primarily to the NIF chamber dynamics. The key design issues are the ablation of the chamber structures, transport of the vapor through the chamber and the condensation or deposition processes of those vaporized materials. An understanding of these processes is essential in developing a concept for protecting the final optics debris shields from an excessive coating (> 10 {Angstrom}) of target debris and ablated material, thereby prolonging their lifetime between change- outs. At Berkeley, we have studied the physical issues of the ablation process and the effects of varying materials, the condensation process of the vaporized material, and design schemes that can lower the threat posed to the debris shields by these processes. In addition to the work described briefly above, we performed extensive analysis of the target-chamber thermal response to in- chamber CO{sub 2} Cleaning and of work performed to model the behavior of silica vapor. The work completed this year has been published in several papers and a dissertation [1-6]. This report provides a summary of the work completed this year, as well as copies

  6. Development of a EUV Test Facility at the Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    West, Edward; Pavelitz, Steve; Kobayashi, Ken; Robinson, Brian; Cirtain, Johnathan; Gaskin, Jessica; Winebarger, Amy

    2011-01-01

    This paper will describe a new EUV test facility that is being developed at the Marshall Space Flight Center (MSFC) to test EUV telescopes. Two flight programs, HiC - high resolution coronal imager (sounding rocket) and SUVI - Solar Ultraviolet Imager (GOES-R), set the requirements for this new facility. This paper will discuss those requirements, the EUV source characteristics, the wavelength resolution that is expected and the vacuum chambers (Stray Light Facility, Xray Calibration Facility and the EUV test chamber) where this facility will be used.

  7. The Mark III vertex chamber and prototype test results

    SciTech Connect

    Grab, C.

    1987-07-01

    A vertex chamber has been constructed for use in the Mark III experiment. The chamber is positioned inside the current main drift chamber and will be used to trigger data collection, to aid in vertex reconstruction, and to improve the momentum resolution. This paper discusses the chamber's construction and performance and tests of the prototype.

  8. Chamber LIDAR measurements of aerosolized biological simulants

    NASA Astrophysics Data System (ADS)

    Brown, David M.; Thrush, Evan P.; Thomas, Michael E.; Siegrist, Karen M.; Baldwin, Kevin; Quizon, Jason; Carter, Christopher C.

    2009-05-01

    A chamber aerosol LIDAR is being developed to perform well-controlled tests of optical scattering characteristics of biological aerosols, including Bacillus atrophaeus (BG) and Bacillus thuringiensis (BT), for validation of optical scattering models. The 1.064 μm, sub-nanosecond pulse LIDAR allows sub-meter measurement resolution of particle depolarization ratio or backscattering cross-section at a 1 kHz repetition rate. Automated data acquisition provides the capability for real-time analysis or recording. Tests administered within the refereed 1 cubic meter chamber can provide high quality near-field backscatter measurements devoid of interference from entrance and exit window reflections. Initial chamber measurements of BG depolarization ratio are presented.

  9. Thermal Vacuum Chamber Repressurization with Instrument Purging

    NASA Technical Reports Server (NTRS)

    Woronowicz, Michael

    2016-01-01

    At the end of James Webb Space Telescope (JWST) OTIS (Optical Telescope Element-OTE-Integrated Science Instrument Module-ISIM) cryogenic vacuum testing in NASA Johnson Space Centers (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are mooting the idea that chamber particulate material stirred up by the repressurization process may be kept from falling into the ISIM interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This memo describes development of a series of models designed to describe this process. These are strung together in tandem to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.

  10. Thermal Vacuum Chamber Repressurization with Instrument Purging

    NASA Technical Reports Server (NTRS)

    Woronowicz, Michael S.

    2014-01-01

    At the conclusion of cryogenic vacuum testing of the James Webb Space Telescope Optical Telescope Element Integrated Science Instrument Module (JWST-OTIS) in NASA Johnson Space Center’s (JSCs) thermal vacuum (TV) Chamber A, contamination control (CC) engineers are postulating that chamber particulate material stirred up by the repressurization process may be kept from falling into the Integrated Science Instrument Module (ISIM) interior to some degree by activating instrument purge flows over some initial period before opening the chamber valves. This manuscript describes development of a series of models designed to describe this process. The models are strung together in tandem with a fictitious set of conditions to estimate overpressure evolution from which net outflow velocity behavior may be obtained. Creeping flow assumptions are then used to determine the maximum particle size that may be kept suspended above the ISIM aperture, keeping smaller particles from settling within the instrument module.

  11. High temperature thrust chamber for spacecraft

    NASA Technical Reports Server (NTRS)

    Chazen, Melvin L. (Inventor); Mueller, Thomas J. (Inventor); Kruse, William D. (Inventor)

    1998-01-01

    A high temperature thrust chamber for spacecraft (20) is provided herein. The high temperature thrust chamber comprises a hollow body member (12) having an outer surface and an internal surface (16) defining the high temperature chamber (10). The body member (12) is made substantially of rhenium. An alloy (18) consisting of iridium and at least alloying metal selected of the group consisting of rhodium, platinum and palladium is deposited on at least a portion of the internal surface (16) of the body member (12). The iridium and the alloying metal are electrodeposited onto the body member (12). A HIP cycle is performed upon the body member (12) to cause the coating of iridium and the alloying metal to form the alloy (18) which protects the body member (12) from oxidation.

  12. Fission chambers designer based on Monte Carlo techniques working in current mode and operated in saturation regime

    NASA Astrophysics Data System (ADS)

    Antolínez, Alfonso; Rapisarda, David

    2016-07-01

    Fission chambers have become one of the main devices for the measurement of neutron fluxes in nuclear facilities; including fission reactors, future fusion ones, spallation sources, etc. The main goal of a fission chamber is to estimate the neutron flux inside the facility, as well as instantaneous changes in the irradiation conditions. A Monte Carlo Fission Chamber Designer (MCFCD) has been developed in order to assist engineers in the complete design cycle of the fission chambers. So far MCFCD focuses on the most important neutron reactions taking place in a thermal nuclear reactor. A theoretical model describing the most important outcomes in fission chambers design has been developed, including the expected electrical signals (current intensity and drop in potential) and, current-polarization voltage characteristics (sensitivity and saturation plateau); the saturation plateau is the zone of the saturation curve where the output current is proportional to fission rate; fission chambers work in this region. Data provided by MCFCD are in good agreement with measurements available.

  13. Simulation of BaBar Drift Chamber

    SciTech Connect

    Anderson, Rachel; /Wisconsin U., Eau Claire /SLAC

    2006-09-27

    The BaBar drift chamber (DCH) is used to measure the properties of charged particles created from e{sup +}e{sup -} collisions in the PEP-II asymmetric-energy storage rings by making precise measurements of position, momentum and ionization energy loss (dE/dx). In October of 2005, the PEP-II storage rings operated with a luminosity of 10 x 10{sup 33} cm{sup -2}s{sup -1}; the goal for 2007 is a luminosity of 20 x 10{sup 33} cm{sup -2}s{sup -1}, which will increase the readout dead time, causing uncertainty in drift chamber measurements to become more significant in physics results. The research described in this paper aims to reduce position and dE/dx uncertainties by improving our understanding of the BaBar drift chamber performance. A simulation program--called GARFIELD--is used to model the behavior of the drift chamber with adjustable parameters such as gas mixture, wire diameter, voltage, and magnetic field. By exploring the simulation options offered in GARFIELD, we successfully produced a simulation model of the BaBar drift chamber. We compared the time-to-distance calibration from BaBar to that calculated by GARFIELD to validate our model as well as check for discrepancies between the simulated and calibrated time-to-distance functions, and found that for a 0{sup o} entrance angle there is a very good match between calibrations, but at an entrance angle of 90{sup o} the calibration breaks down. Using this model, we also systematically varied the gas mixture to find one that would optimize chamber operation, which showed that the gas mixture of 80:20 Helium:isobutane is a good operating point, though more calculations need to be done to confirm that it is the optimal mixture.

  14. Lightweight Chambers for Thrust Cell Applications

    NASA Technical Reports Server (NTRS)

    Elam, S.; Effinger, M.; Holmes, R.; Lee, J.; Jaskowiak, M.

    2000-01-01

    Traditional metals like steel and copper alloys have been used for many years to fabricate injector and chamber components of thruster assemblies. While the materials perform well, reducing engine weights would help existing and future vehicles gain performance and payload capability. It may now be possible to reduce current thruster weights up to 50% by applying composite materials. In this task, these materials are being applied to an existing thrust cell design to demonstrate new fabrication processes and potential weight savings. Two ceramic matrix composite (CMC) designs, three polymer matrix composite (PMC) designs, and two metal matrix composite (MMC) designs are being fabricated as small chamber demonstration units. In addition, a new alloy of copper, chrome, and niobium (Cu-8Cr-4Nb) is being investigated for thrust chamber liners since it offers higher strength and increased cycle life over traditional alloys. This new alloy is being used for the liner in each MMC and PMC demonstration unit. During June-August of 2000, hot-fire testing of each unit is planned to validate designs in an oxygen/hydrogen environment at chamber pressures around 850 psi. Although the weight savings using CMC materials is expected to be high, they have proven to be much harder to incorporate into chamber designs based on current fabrication efforts. However, the PMC & MMC concepts using the Cu-8Cr-4Nb liner are nearly complete and ready for testing. Additional efforts intend to use the PMC & MMC materials to fabricate a full size thrust chamber (60K lb(sub f) thrust class). The fabrication of this full size unit is expected to be complete by October 2000, followed by hot-fire testing in November-December 2000.

  15. The National Ignition Facility

    SciTech Connect

    Miller, G H

    2003-12-19

    The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter diameter target chamber and room for 100 diagnostics. NIF is the world's largest and most energetic laser experimental system, providing a scientific center to study inertial confinement fusion and matter at extreme energy densities and pressures. NIF's energetic laser beams will compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. Other NIF experiments will study physical processes at temperatures approaching 10{sup 8} K and 10'' bar; conditions that exist naturally only in the interior of stars and planets. NIF has completed the first phases of its laser commissioning program. The first four beams of NIF have generated 106 kilojoules in 23-ns pulses of infrared light and over 16 kJ in 3.5 ns pulses at the third harmonic (351 nm). NIF's target experimental systems are being commissioned and experiments have begun. This paper discusses NIF's current and future experimental capability, plans for diagnostics, cryogenic target systems, specialized optics for experiments, and potential enhancements to NIF such as multi-color laser operation and high-energy short pulse operation.

  16. NSTAR Extended Life Test Discharge Chamber Flake Analysis

    NASA Technical Reports Server (NTRS)

    deGroh, Kim K.; Banks, Bruce A.; Karniotis, Christina A.

    2005-01-01

    The Extended Life Test (ELT) of the NASA Solar Electric Propulsion Technology Readiness (NSTAR) ion thruster was concluded after 30,352 hours of operation. The ELT was conducted using the Deep Space 1 (DS1) back-up flight engine, a 30 cm diameter xenon ion thruster. Post-test inspection of the ELT engine revealed numerous contaminant flakes distributed over the bottom of the cylindrical section of the anode within the discharge chamber (DC). Extensive analyses were conducted to determine the source of the particles, which is critical to the understanding of degradation mechanisms of long life ion thruster operation. Analyses included: optical microscopy (OM) and particle length histograms, field emission scanning electron microscopy (FESEM) combined with energy dispersive spectroscopy (EDS), and atomic oxygen plasma exposure tests. Analyses of the particles indicate that the majority of the DC flakes consist of a layered structure, typically with either two or three layers. The flakes comprising two layers were typically found to have a molybdenum-rich (Mo-rich) layer on one side and a carbon-rich (C-rich) layer on the other side. The flakes comprising three layers were found to be sandwich-like structures with Mo-rich exterior layers and a C-rich interior layer. The presence of the C-rich layers indicates that these particles were produced by sputter deposition build-up on a surface external to the discharge chamber from ion sputter erosion of the graphite target in the test chamber. This contaminant layer became thick enough that particles spalled off, and then were electro-statically attracted into the ion thruster interior, where they were coated with Mo from internal sputter erosion of the screen grid and cathode components. Atomic oxygen tests provided evidence that the DC chamber flakes are composed of a significant fraction of carbon. Particle size histograms further indicated that the source of the particles was spalling of carbon flakes from downstream

  17. Sandia National Laboratories' new high level acoustic test facility

    SciTech Connect

    Rogers, J. D.; Hendrick, D. M.

    1989-01-01

    A high intensity acoustic test facility has been designed and is under construction at Sandia National Laboratories in Albuquerque, NM. The chamber is designed to provide an acoustic environment of 154dB (re 20 {mu}Pa) overall sound pressure level over the bandwidth of 50 Hz to 10,000 Hz. The chamber has a volume of 16,000 cubic feet with interior dimensions of 21.6 ft {times} 24.6 ft {times} 30 ft. The construction of the chamber should be complete by the summer of 1990. This paper discusses the design goals and constraints of the facility. The construction characteristics are discussed in detail, as are the acoustic performance design characteristics. The authors hope that this work will help others in designing acoustic chambers. 12 refs., 6 figs.

  18. Steady State Vacuum Ultraviolet Exposure Facility With Automated Calibration Capability

    NASA Technical Reports Server (NTRS)

    Stueber, Thomas J.; Sechkar, Edward A.; Dever, Joyce A.; Banks, Bruce A.

    2000-01-01

    NASA Glenn Research Center at Lewis Field designed and developed a steady state vacuum ultraviolet automated (SSVUVa) facility with in situ VUV intensity calibration capability. The automated feature enables a constant accelerated VUV radiation exposure over long periods of testing without breaking vacuum. This test facility is designed to simultaneously accommodate four isolated radiation exposure tests within the SSVUVa vacuum chamber. Computer-control of the facility for long, term continuous operation also provides control and recording of thermocouple temperatures, periodic recording of VUV lamp intensity, and monitoring of vacuum facility status. This paper discusses the design and capabilities of the SSVUVa facility.

  19. Sealed Plant-Growth Chamber For Clinostat

    NASA Technical Reports Server (NTRS)

    Brown, Christopher S.; Dreschel, Thomas W.

    1993-01-01

    Laboratory chamber for growing plants used to measure photosynthesis and respiration in simulated microgravity. Holds plant specimens while rotated on clinostat, see article, "Clinostat Delivers Power To Plant-Growth Cabinets" (KSC-11537). Provides way of comparing gas-exchange rates of plants rotated horizontally on clinostat with those of stationary or vertically rotated plants. Gas extracted for analysis without stopping clinostat. Chamber includes potlike base and cylindrical cover, both made of transparent acrylic pipe. Gasket forms seal between cover and bottom plate of base. Cover bolted to pot baseplate, which in turn bolted to clinostat.

  20. Quasi-Porous Plug With Vortex Chamber

    NASA Technical Reports Server (NTRS)

    Walsh, J. V.

    1985-01-01

    Pressure-letdown valve combines quasi-porous-plug and vortex-chamber in one controllable unit. Valve useful in fossil-energy plants for reducing pressures in such erosive two-phase process streams as steam/water, coal slurries, or combustion gases with entrained particles. Quasi-Porous Plug consists of plenums separated by perforated plates. Number or size of perforations increases with each succeeding stage to compensate for expansion. In Vortex Chamber, control flow varies to control swirl and therefore difference between inlet and outlet pressures.

  1. Measurements of a 1/4-scale model of an explosives firing chamber

    SciTech Connect

    Pastrnak, J.W.; Baker, C.F.; Simmons, L.F.

    1995-01-27

    In anticipation of increasingly stringent environmental regulations, Lawrence Livermore National Laboratory (LLNL) proposes to construct a 60-kg firing chamber to provide blast-effects containment for most of its open-air, high-explosive, firing operations. Even though these operations are within current environmental limits, containment of the blast effects and hazardous debris will further drastically reduce emissions to the environment and minimize the generated hazardous waste. The major design consideration of such a chamber is its overall structural dynamic response in terms of long-term containment of all blast effects from repeated internal detonations of high explosives. Another concern is how much other portions of the facility outside the firing chamber must be hardened to ensure personnel protection in the event of an accidental detonation while the chamber door is open. To assess these concerns, a 1/4-scale replica model of the planned contained firing chamber was designed, constructed, and tested with scaled explosive charges ranging from 25 to 125% of the operational explosives limit of 60 kg. From 16 detonations of high explosives, 880 resulting strains, blast pressures, and temperatures within the model were measured to provide information for the final design. Factors of safety for dynamic yield of the firing chamber structure were calculated and compared to the design criterion of totally elastic response. The rectangular, reinforced-concrete chamber model exhibited a lightly damped vibrational response that placed the structure in alternating cycles of tension and compression. During compression, both the reinforcing steel and the concrete remained elastic.

  2. Outdoor smog chamber experiments to test photochemical models. Final report May 78-May 81

    SciTech Connect

    Feffries, H.E.; Kamens, R.M.; Sexron, K.G.; Gerhardt, A.A.

    1982-04-01

    The smog chamber facility of the University of North Carolina was used in a study to provide experimental data for developing and testing kinetic mechanisms of photochemical smog formation. The smog chamber, located outdoors in rural North Carolina, is an A-frame structure covered with Teflon film. Because the chamber is partitioned into two sections, each with a volume of 156 cu m, two experiments can be conducted simultaneously. The dual chamber is operated under natural conditions of solar radiation, temperature, and relative humidity. In this study, 115 dual all-day experiments were conducted using NOx and a variety of organic species. The organic compounds investigated included various paraffins, olefins, aromatics and oxygenates, both singly and in mixtures of two or more components. In this report the data collected over the three-year period of the study are described. The experimental procedures and analytical methods used in this study and the limitations and uncertainties of the data are discussed. Guidance for modeling of the data is also given, including a detailed discussion of how to estimate photolytic rate constants from the available UV and total solar radiation data and how to treat such chamber artifacts as dilution, wall sources and losses of pollutants, and reactivity of the background air.

  3. Quality assurance for radon exposure chambers at the National Air and Radiation Environmental Laboratory, Montgomery, Alabama

    SciTech Connect

    Semler, M.O.; Sensintaffar, E.L.

    1993-12-31

    The Office of Radiation and Indoor Air, U.S. Environmental Protection Agency (EPA), operates six radon exposure chambers in its two laboratories, the National Air and Radiation Environmental Laboratory (NAREL) in Montgomery, Alabama, and the Las Vegas Facility, Las Vegas, Nevada. These radon exposure chambers are used to calibrate and test portable radon measuring instruments, test commercial suppliers of radon measurement services through the Radon Measurement Proficiency Program, and expose passive measurement devices to known radon concentrations as part of a quality assurance plan for federal and state studies measuring indoor radon concentrations. Both laboratories participate in national and international intercomparisons for the measurement of radon and are presently working with the National Institute of Standards and Technology (NIST) to receive a certificate of traceability for radon measurements. NAREL has developed an estimate of the total error in its calibration of each chamber`s continuous monitors as part of an internal quality assurance program. This paper discusses the continuous monitors and their calibration for the three chambers located in Montgomery, Alabama, as well as the results of the authors intercomparisons and total error analysis.

  4. Experiment 8: Environmental Conditions in the ASTROCULTURE(trademark) Plant Chamber During the USML-2 Mission

    NASA Technical Reports Server (NTRS)

    Bula, R. J.; Zhou, Weijia; Yetka, R. A.; Draeger, N. A.

    1998-01-01

    Conducting plant research to assess the impact of microgravity on plant growth and development requires a plant chamber that has the capability to control other environmental parameters involved in plant growth and development. The environmental control in a space-based plant chamber must be equivalent to that available in such facilities used for terrestrial plant research. Additionally, plants are very sensitive to a number of atmospheric gaseous materials. Thus, the atmosphere of a plant chamber must be isolated from the space vehicle atmosphere, and the plant growth unit should have the capability to remove any such deleterious materials that may impact plant growth and development. The Wisconsin Center for Space Automation and Robotics (WCSAR), University of Wisconsin-Madison, has developed a totally enclosed controlled environment plant growth unit. The flight unit was used to support the ASTROCULTURE(TM) experiment conducted during the USML-2 mission. The experiment had two major objectives: 1) Provide further validation of the flight unit to control the experiment-defined environmental parameters in the plant chamber, and 2) support a plant experiment to assess the capability of potato plant material to produce tubers in microgravity. This paper describes the temperature, humidity, and carbon dioxide conditions of the plant chamber during the mission, from launch to landing. Another paper will present the plant response data.

  5. A space simulation test chamber development for the investigation of radiometric properties of materials

    NASA Technical Reports Server (NTRS)

    Enlow, D. L.

    1972-01-01

    The design, fabrication, and preliminary utilization of a thermal vacuum space simulation facility are discussed. The facility was required to perform studies on the thermal radiation properties of materials. A test chamber was designed to provide high pumping speed, low pressure, a low photon level radiation background (via high emissivity, coated, finned cryopanels), internal heat sources for rapid warmup, and rotary and linear motion of the irradiated materials specimen. The radiation detection system consists of two wideband infrared photoconductive detectors, their cryogenic coolers, a cryogenic-cooled blackbody source, and a cryogenic-cooled optical radiation modulator.

  6. Threshold bubble chamber for measurement of knock-on DT neutron tails from magnetic and inertial confinement experiments

    SciTech Connect

    Fisher, R.K.; Zaveryaev, V.S.; Trusillo, S.V.

    1997-01-01

    We propose a new {open_quotes}threshold{close_quotes} bubble chamber detector for measurement of knock-on neutron tails. These energetic neutrons result from fusion reactions involving energetic fuel ions created by alpha knock-on collisions in tokamak and other magnetic confinement experiments, and by both alpha and neutron knock-on collisions in inertial confinement fusion (ICF) experiments. The energy spectrum of these neutrons will yield information on the alpha population and energy distribution in tokamaks, and on alpha target physics and {rho}R measurements in ICF experiments. The bubble chamber should only detect neutrons with energies above a selectable threshold energy controlled by the bubble chamber pressure. The bubble chamber threshold mechanism, detection efficiency, and proposed applications to the International Thermonuclear Experimental Reactor and National Ignition Facility experiments will be discussed. {copyright} {ital 1997 American Institute of Physics.}

  7. Threshold bubble chamber for measurement of knock-on DT neutron tails from magnetic and inertial confinement experiments

    SciTech Connect

    Fisher, R.K.; Zaveryaev, V.S.; Trusillo, S.V.

    1996-07-01

    We propose a new {open_quotes}threshold{close_quotes} bubble chamber detector for measurement of knock-on neutron tails. These energetic neutrons result from fusion reactions involving energetic fuel ions created by alpha knock-on collisions in tokamak and other magnetic confinement experiments, and by both alpha and neutron knock-on collisions in inertial confinement fusion (ICF) experiments. The energy spectrum of these neutrons will yield information on the alpha population and energy distribution in tokamaks, and on alpha target physics and {rho}R measurements in ICF experiments. The bubble chamber should only detect neutrons with energies above a selectable threshold energy controlled by the bubble chamber pressure. The bubble chamber threshold mechanism, detection efficiency, and proposed applications to the International Thermonuclear Experimental Reactor (ITER) and National Ignition Facility (NIF) experiments will be discussed.

  8. SEPAC system test in NASDA space chamber

    NASA Astrophysics Data System (ADS)

    Obayashi, T.; Kuriki, K.; Kawashima, N.; Nagatomo, M.; Kudo, I.; Ninomiya, K.; Ushirokawa, A.; Ejiri, M.; Sasaki, S.

    1980-01-01

    Test results of the second NASDA space chamber test using SEPAC (Space Experiment with Particle Acceleration) prototype models are reviewed. A safety level of electrical charge is determined, the electromagnetic interference effect caused by an electron beam and MPD arcjet firing is evaluated, and beam spread for EBA software mask design is measured.

  9. A reusable prepositioned ATP reaction chamber

    NASA Technical Reports Server (NTRS)

    Hoffman, D. G.

    1972-01-01

    Luminescence biometer detects presence of life by means of light-emitting chemical reaction of luciferin and luciferase with adenosine triphosphate (ATP) that occurs in all living cells. Amount of light in reaction chamber is measured to determine presence and extent of life.

  10. Lifetime tests for MAC vertex chamber

    SciTech Connect

    Nelson, H.N.

    1986-07-01

    A vertex chamber for MAC was proposed to increase precision in the measurement of the B hadron and tau lepton lifetimes. Thin-walled aluminized mylar drift tubes were used for detector elements. A study of radiation hardness was conducted under the conditions of the proposed design using different gases and different operating conditions. (LEW)

  11. Detecting dark matter with scintillating bubble chambers

    NASA Astrophysics Data System (ADS)

    Zhang, Jianjie; Dahl, C. Eric; Jin, Miaotianzi; Baxter, Daniel

    2016-03-01

    Threshold based direct WIMP dark matter detectors such as the superheated bubble chambers developed by the PICO experiment have demonstrated excellent electron-recoil and alpha discrimination, excellent scalability, ease of change of target fluid, and low cost. However, the nuclear-recoil like backgrounds have been a limiting factor in their dark matter sensitivity. We present a new type of detector, the scintillating bubble chamber, which reads out the scintillation pulse of the scattering events as well as the pressure, temperature, acoustic traces, and bubble images as a conventional bubble chamber does. The event energy provides additional handle to discriminate against the nuclear-recoil like backgrounds. Liquid xenon is chosen as the target fluid in our prototyping detector for its high scintillation yield and suitable vapor pressure which simplifies detector complexity. The detector can be used as an R&D tool to study the backgrounds present in the current PICO bubble chambers or as a prototype for standalone dark matter detectors in the future. Supported by DOE Grant DE-SC0012161.

  12. Miniature reaction chamber and devices incorporating same

    DOEpatents

    Mathies, Richard A.; Woolley, Adam T.

    2000-10-17

    The present invention generally relates to miniaturized devices for carrying out and controlling chemical reactions and analyses. In particular, the present invention provides devices which have miniature temperature controlled reaction chambers for carrying out a variety of synthetic and diagnostic applications, such as PCR amplification, nucleic acid hybridization, chemical labeling, nucleic acid fragmentation and the like.

  13. Anterior Chamber Live Loa loa: Case Report.

    PubMed

    Kagmeni, G; Cheuteu, R; Bilong, Y; Wiedemann, P

    2016-01-01

    We reported a case of unusual intraocular Loa loa in a 27-year-old patient who presented with painful red eye. Biomicroscopy revealed a living and active adult worm in the anterior chamber of the right eye. After surgical extraction under local anesthesia, parasitological identification confirmed L. loa filariasis. PMID:27441005

  14. Acoustical-Levitation Chamber for Metallurgy

    NASA Technical Reports Server (NTRS)

    Barmatz, M. B.; Trinh, E.; Wang, T. G.; Elleman, D. D.; Jacobi, N.

    1983-01-01

    Sample moved to different positions for heating and quenching. Acoustical levitation chamber selectively excited in fundamental and second-harmonic longitudinal modes to hold sample at one of three stable postions: A, B, or C. Levitated object quickly moved from one of these positions to another by changing modes. Object rapidly quenched at A or C after heating in furnace region at B.

  15. Chamber transport for heavy ion fusion

    NASA Astrophysics Data System (ADS)

    Olson, Craig L.

    2014-01-01

    A brief review is given of research on chamber transport for HIF (heavy ion fusion) dating from the first HIF Workshop in 1976 to the present. Chamber transport modes are categorized into ballistic transport modes and channel-like modes. Four major HIF reactor studies are summarized (HIBALL-II, HYLIFE-II, Prometheus-H, OSIRIS), with emphasis on the chamber transport environment. In general, many beams are used to provide the required symmetry and to permit focusing to the required small spots. Target parameters are then discussed, with a summary of the individual heavy ion beam parameters required for HIF. The beam parameters are then classified as to their line charge density and perveance, with special emphasis on the perveance limits for radial space charge spreading, for the space charge limiting current, and for the magnetic (Alfven) limiting current. The major experiments on ballistic transport (SFFE, Sabre beamlets, GAMBLE II, NTX, NDCX) are summarized, with specific reference to the axial electron trapping limit for charge neutralization. The major experiments on channel-like transport (GAMBLE II channel, GAMBLE II self-pinch, LBNL channels, GSI channels) are discussed. The status of current research on HIF chamber transport is summarized, and the value of future NDCX-II transport experiments for the future of HIF is noted.

  16. Simple chamber facilitates chemiluminescent detection of bacteria

    NASA Technical Reports Server (NTRS)

    Marts, E. C.; Wilkins, J. R.

    1970-01-01

    Test chamber enables rapid estimation of bacteria in a test sample through the reaction of luminol and an oxidant with the cytochrome C portion of certain species of bacteria. Intensity of the light emitted in the reaction is a function of the specific bacteria in the test sample.

  17. Multiphysics Nuclear Thermal Rocket Thrust Chamber Analysis

    NASA Technical Reports Server (NTRS)

    Wang, Ten-See

    2005-01-01

    The objective of this effort is t o develop an efficient and accurate thermo-fluid computational methodology to predict environments for hypothetical thrust chamber design and analysis. The current task scope is to perform multidimensional, multiphysics analysis of thrust performance and heat transfer analysis for a hypothetical solid-core, nuclear thermal engine including thrust chamber and nozzle. The multiphysics aspects of the model include: real fluid dynamics, chemical reactivity, turbulent flow, and conjugate heat transfer. The model will be designed to identify thermal, fluid, and hydrogen environments in all flow paths and materials. This model would then be used to perform non- nuclear reproduction of the flow element failures demonstrated in the Rover/NERVA testing, investigate performance of specific configurations and assess potential issues and enhancements. A two-pronged approach will be employed in this effort: a detailed analysis of a multi-channel, flow-element, and global modeling of the entire thrust chamber assembly with a porosity modeling technique. It is expected that the detailed analysis of a single flow element would provide detailed fluid, thermal, and hydrogen environments for stress analysis, while the global thrust chamber assembly analysis would promote understanding of the effects of hydrogen dissociation and heat transfer on thrust performance. These modeling activities will be validated as much as possible by testing performed by other related efforts.

  18. Anterior Chamber Live Loa loa: Case Report

    PubMed Central

    Kagmeni, G.; Cheuteu, R.; Bilong, Y.; Wiedemann, P.

    2016-01-01

    We reported a case of unusual intraocular Loa loa in a 27-year-old patient who presented with painful red eye. Biomicroscopy revealed a living and active adult worm in the anterior chamber of the right eye. After surgical extraction under local anesthesia, parasitological identification confirmed L. loa filariasis. PMID:27441005

  19. Presenting Chamber Music to Young Children

    ERIC Educational Resources Information Center

    Smith, Terry Fonda

    2011-01-01

    The number of professional ensembles and organizations with dedicated outreach concerts has been steadily increasing over the past decade. More recently, educational concerts pairing chamber music with young children have been documented. The work presented in this article is a study in the efficacy and feasibility of this format. Various music…

  20. Try Chamber Music--Here's How.

    ERIC Educational Resources Information Center

    Rudaitis, Cheryl

    1995-01-01

    Profiles four middle school teachers maintaining early chamber music programs. The teachers advise varying degrees of musical competency before students begin the program, but all of them caution against starting too soon. They also stress the importance of purchasing early music scores and establishing rehearsal times. (MJP)

  1. Chamber for Aerosol Deposition of Bioparticles

    NASA Technical Reports Server (NTRS)

    Kern, Roger; Kirschner, Larry

    2008-01-01

    Laboratory apparatus is depicted that is a chamber for aerosol deposition of bioparticles on surfaces of test coupons. It is designed for primary use in inoculating both flat and three-dimensional objects with approximately reproducible, uniform dispersions of bacterial spores of the genus Bacillus so that the objects could be used as standards for removal of the spores by quantitative surface sampling and/or cleaning processes. The apparatus is also designed for deposition of particles other than bacterial spores, including fungal spores, viruses, bacteriophages, and standard micron-sized beads. The novelty of the apparatus lies in the combination of a controllable nebulization system with a settling chamber large enough to contain a significant number of test coupons. Several companies market other nebulizer systems, but none are known to include chambers for deposition of bioparticles to mimic the natural fallout of bioparticles. The nebulization system is an expanded and improved version of commercially available aerosol generators that include nebulizers and drying columns. In comparison with a typical commercial aerosol generator, this system includes additional, higher-resolution flowmeters and an additional pressure regulator. Also, unlike a typical commercial aerosol generator, it includes stopcocks for separately controlling flows of gases to the nebulizer and drying column. To maximize the degree of uniformity of dispersion of bioaerosol, the chamber is shaped as an axisymmetrical cylinder and the aerosol generator is positioned centrally within the chamber and aimed upward like a fountain. In order to minimize electric charge associated with the aerosol particles, the drying column is made of aluminum, the drying column is in direct contact with an aluminum base plate, and three equally spaced Po-210 antistatic strips are located at the exit end of the drying column. The sides and top of the chamber are made of an acrylic polymer; to prevent

  2. Thermistors Used in Climatic Chamber at High Temperature and Humidity

    NASA Astrophysics Data System (ADS)

    van Geel, J. L. W. A.; Bosma, R.; van Wensveen, J.; Peruzzi, A.

    2015-03-01

    In 2011, VSL initiated the development of a facility for a relative humidity between and for calibrating high-temperature relative humidity sensors at pressures other than atmospheric. The setup for calculating the relative humidity uses the dew-point temperature, measured by a chilled mirror hygrometer, and the temperature distribution in the chamber, measured by a series of thermistors. This paper describes the results of thermal tests performed on the thermistors to ensure that they meet the requirements of the humidity calibration facility. Different types of thermistors were evaluated up to , and the selected type showed a short-term drift of less than 2 mK. Exposure of these thermistors to temperatures up to gave an initial hysteresis of 40 mK, but after this initial hysteresis, the hysteresis, over the range from up to , was less than 10 mK. Use of a digital multimeter, with a low-power option, limited the self-heating of the thermistors, over the range from up to , to less than 5 mK. During use in the new setup, the thermistors were exposed to changing humidities between 1 %Rh and 90 %Rh and temperatures up to , showing drifts of less than 10 mK.

  3. Secondary organic aerosol formation from gasoline vehicle emissions in a new mobile environmental reaction chamber

    NASA Astrophysics Data System (ADS)

    Platt, S. M.; El Haddad, I.; Zardini, A. A.; Clairotte, M.; Astorga, C.; Wolf, R.; Slowik, J. G.; Temime-Roussel, B.; Marchand, N.; Ježek, I.; Drinovec, L.; Močnik, G.; Möhler, O.; Richter, R.; Barmet, P.; Bianchi, F.; Baltensperger, U.; Prévôt, A. S. H.

    2012-10-01

    We present a new mobile environmental reaction chamber for the simulation of the atmospheric aging of aerosols from different emissions sources without limitation from the instruments or facilities available at any single site. The chamber can be mounted on a trailer for transport to host facilities or for mobile measurements. Photochemistry is simulated using a set of 40 UV lights (total power 4 KW). Characterisation of the emission spectrum of these lights shows that atmospheric photochemistry can be accurately simulated over a range of temperatures from -7-25 °C. A photolysis rate of NO2, JNO2, of (8.0 ± 0.7) × 10-3 molecules cm-3 s-1 was determined at 25 °C. Further, we present the first application of the mobile chamber and demonstrate its utility by quantifying primary organic aerosol (POA) emission and secondary organic aerosol (SOA) production from a Euro 5 light duty gasoline vehicle. Exhaust emissions were sampled during the New European Driving Cycle (NEDC), the standard driving cycle for European regulatory purposes, and injected into the chamber. The relative concentrations of oxides of nitrogen (NOx) and total hydrocarbon (THC) during the aging of emissions inside the chamber were controlled using an injection system developed as a part of the new mobile chamber set up. Total OA (POA + SOA) emission factors of (370 ± 18) × 10-3 g kg-1 fuel, or (14.6 ± 0.8) × 10-3 g km-1, after aging, were calculated from concentrations measured inside the smog chamber during two experiments. The average SOA/POA ratio for the two experiments was 15.1, a much larger increase than has previously been seen for diesel vehicles, where smog chamber studies have found SOA/POA ratios of 1.3-1.7. Due to this SOA formation, carbonaceous particulate matter (PM) emissions from a gasoline vehicle may approach those of a diesel vehicle of the same class. Furthermore, with the advent of emission controls requiring the use of diesel particle filters, gasoline vehicle emissions

  4. Four chamber pacing in dilated cardiomyopathy.

    PubMed

    Cazeau, S; Ritter, P; Bakdach, S; Lazarus, A; Limousin, M; Henao, L; Mundler, O; Daubert, J C; Mugica, J

    1994-11-01

    A 54-year-old man received a four chamber pacing system for severe congestive heart failure (NYHA functional Class IV). His ECG showed a left bundle branch block (200-msec QRS duration) with 200-msec PR interval, normal QRS axis, and 90-msec interatrial interval. An acute hemodynamic study with insertion of four temporary leads was performed prior to the implant, which demonstrated a significant increase in cardiac output and decrease of pulmonary capillary wedge pressure. A permanent pacemaker was implanted based on the encouraging results of the acute study. The right chamber leads were introduced by cephalic and subclavian approaches. The left atrium was paced with a coronary sinus lead, Medtronic SP 2188-58 model. An epicardial Medtronic 5071 lead was placed on the LV free wall. The four leads were connected to a standard bipolar DDD pacemaker, Chorus 6234. The two atrial leads were connected via a Y-connector to the atrial channel of the pacemaker with a bipolar pacing configuration. The two ventricular leads were connected in a similar fashion to the ventricular channel of the device. The right chamber leads were connected to the distal poles. The left chamber leads were connected to the proximal poles of the pacemaker. Six weeks later, the patient's clinical status improved markedly with a weight loss of 17 kg and disappearance of peripheral edema. His functional class was reduced to NYHA II. Four chamber pacing is technically feasible. In patients with evidence of interventricular dyssynchrony, this original pacing mode probably provides a mechanical activation sequence closer to the natural one.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Test plan pressure fed thrust chamber technology

    NASA Technical Reports Server (NTRS)

    Dunn, Glenn

    1990-01-01

    Aerojet is developing the technology for the design of a reliable, low cost, efficient, and lightweight LOX/RP-1 pressure fed engine. This technology program is a direct result of Aerojet's liquid rocket booster (LRB) study and previous NASA studies that identified liquid engines using high bulk density hydrocarbon fuels as very attractive for a space transportation system (STS). Previous large thrust LOX/RP-1 engine development programs were characterized by costly development problems due to combustion instability damage. The combustion stability solution was typically obtained through trial and error methods of minimizing instability damage by degrading engine performance. The approach to this program was to utilize existing and newly developed combustion analysis models and design methodology to create a thrust chamber design with features having the potential of producing reliable and efficient operation. This process resulted in an engine design with a unique high thrust-per-element OFO triplet injector utilizing a low cost modular approach. Cost efficient ablative materials are baselined for the injector face and chamber. Technology demonstration will be accomplished through a hot fire test program using appropriately sized subscale hardware. This subscale testing will provide a data base to supplement the current industry data bank and to anchor and validate the applied analysis models and design methodology. Once anchored and validated, these analysis models and design methodology can be applied with greatly increased confidence to design and characterize a large scale pressure fed LOX/RP-1 thrust chamber. The objective of this test program is to generate a data base that can be used to anchor and validate existing analysis models and design methodologies and to provide early concept demonstration of a low cost, efficient LOX/RP-1 thrust chamber. Test conditions and hardware instrumentation were defined to provide data sufficient to characterize combustion

  6. LOTIS facility initial operational capabilities: flexible user interfaces

    NASA Astrophysics Data System (ADS)

    Hutchison, Sheldon B.; Bell, Raymond M., Jr.; Borota, Stephen A.; Cuzner, Gregor J.; Cochrane, Andrew T.

    2010-10-01

    The Large Optical Test and Integration Site (LOTIS) at the Lockheed Martin Space Systems Company in Sunnyvale, CA, has successfully reached Initial Operational Capability (IOC). LOTIS is designed for the verification and testing of optical systems. The facility consists of a large, temperature stabilized vacuum chamber that also functions as a class 10k cleanroom. Within this chamber and atop an advanced vibration-isolation bench are the 6.5 meter diameter LOTIS Collimator and Scene Generator, LOTIS alignment and support equipment. IOC included completion of the entire facility as well as operation of the LOTIS collimator in air. Wavefront properties of the collimator will be described as well as facility vibration isolation properties and turbulence levels within the collimator test chamber. User-specific test capabilities will also be addressed for two major areas of concern.

  7. Pressure Control System Design for a Closed Crop Growth Chamber

    NASA Technical Reports Server (NTRS)

    Tsai, K.; Blackwell, C.; Harper, Lynn D. (Technical Monitor)

    1994-01-01

    The Controlled Ecological Life Support System (CELSS) is an area of active research at NASA. CELSS is a plant-based bioregenerative life support system for long term manned space flights where resupply is costly or impractical. The plants in a CELSS will function to convert the carbon dioxide (exhaled by the crew) into oxygen, purify non-potable water into potable quality water, and provide food for the crew. Prior to implementing a CELSS life support system, one must have knowledge on growing plants in a closed chamber under low gravity. This information will come from research to be conducted on the CELSS Test Facility that will operate on the Space Station Freedom. Currently a ground-based CELSS Test Facility is being built at NASA Ames Research Center. It is called the EDU (Engineering Development Unit). This system will allow researchers to identify issues that may cause difficulties in the development of the CELSS Test Facility and aid in the development of new needed technologies. The EDU consists of a 1 m2 crop growth chamber that is surrounded by a containment enclosure. The containment enclosure isolates the system so there is very little mass and thermal exchange with the ambient. The leakage rate is on the order of 1 % of the enclosure's volume per day (with 0.2S psi pressure difference). The thermal leakage is less than 0.5% of the electrical power supplied to the system per degree Celsius difference from the surrounding. The pressure in the containment enclosure is regulated at 62.5 Pa below the ambient by an active controller. The goal is to maintain this set point for a variety of conditions, such as a range of operating temperatures, heat load variations that occur when the lights are turned on and off, and fluctuations in ambient pressure. In addition certain transition tracking performance is required. This paper illustrates the application of some advanced systems control methods to the task of synthesizing the EDU's pressure control system.

  8. Centrifuge facility conceptual system study. Volume 2: Facility systems and study summary

    NASA Technical Reports Server (NTRS)

    Synnestvedt, Robert (Editor); Blair, Patricia; Cartledge, Alan; Garces-Porcile, Jorge; Garin, Vladimir; Guerrero, Mike; Haddeland, Peter; Horkachuck, Mike; Kuebler, Ulrich; Nguyen, Frank

    1991-01-01

    The Centrifuge Facility is a major element of the biological research facility for the implementation of NASA's Life Science Research Program on Space Station Freedom using nonhuman species (small primates, rodents, plants, insects, cell tissues, etc.). The Centrifuge Facility consists of a variable gravity Centrifuge to provide artificial gravity up to 2 earth G's' a Holding System to maintain specimens at microgravity levels, a Glovebox, and a Service Unit for servicing specimen chambers. The following subject areas are covered: (1) Holding System; (2) Centrifuge System; (3) Glovebox System; (4) Service System; and (5) system study summary.

  9. Facilities Management.

    ERIC Educational Resources Information Center

    Bete, Tim, Ed.

    1998-01-01

    Presents responses from Matt McGovern, "School Planning and Management's" Maintenance and Operations columnist, on the issue of school facility maintenance. McGovern does not believe schools will ever likely meet acceptable levels of maintenance, nor use infrared thermography for assessing roofs, outsource all maintenance work, nor find a pressing…

  10. THE NOAA/EPA FLUID MODELING FACILITY'S CONTRIBUTIONS TO THE UNDERSTANDING OF THE ATMOSPHERIC DISPERSION

    EPA Science Inventory

    Over the past thirty years, scientists at the Environmental Protection Agency's (EPA) Fluid Modeling Facility (FMF) have conducted laboratory studies of fluid flow and pollutant dispersion within three distinct experimental chambers: a meteorological wind tunnel, a water-channel ...

  11. The membrane chamber: a new type of in vitro recording chamber.

    PubMed

    Hill, M R H; Greenfield, S A

    2011-01-30

    In vitro brain slice electrophysiology is a powerful and highly successful technique where a thin slice is cut from the brain and kept alive artificially in a recording chamber. The design of this recording chamber is pivotal to the success and the quality of such experiments. Most often one of two types of chambers is used today, the interface chamber or the submerged chamber. These chambers, however, have the disadvantage that they are limited in either their experimental or their physiological properties respectively. Here we present a new working principle for an in vitro chamber design which aims at combining the advantages of the classical designs whilst overcoming their disadvantages. This is achieved by using a semipermeable membrane on which the slice is placed. The membrane allows for a fast flow of artificial cerebrospinal fluid of up to at least 17 ml/min. Due to a Bernoulli effect, this high speed flow also causes a 64% increase in flow of solution across the membrane on which the slice rests. The fact that the membrane is transparent introduces the possibility of wide field inverted optical imaging to brain slice electrophysiology. The utility of this setup was demonstrated in the recording of local field potential, single cell and voltage sensitive dye imaging data simultaneously from an area smaller then 1/8mm(2). The combination of all these features in the membrane chamber make it a versatile and promising device for many current and future in vitro applications, especially in the regard to optical imaging. PMID:21075142

  12. Convective Regimes in Crystallizing Basaltic Magma Chambers

    NASA Astrophysics Data System (ADS)

    Gilbert, A. J.; Neufeld, J. A.; Holness, M. B.

    2015-12-01

    Cooling through the chamber walls drives crystallisation in crustal magma chambers, resulting in a cumulate pile on the floor and mushy regions at the walls and roof. The liquid in many magma chambers, either the bulk magma or the interstitial liquid in the mushy regions, may convect, driven either thermally, due to cooling, or compositionally, due to fractional crystallization. We have constructed a regime diagram of the possible convective modes in a system containing a basal mushy layer. These modes depend on the large-scale buoyancy forcing characterised by a global Rayleigh number and the proportion of the chamber height constituting the basal mushy region. We have tested this regime diagram using an analogue experimental system composed of a fluid layer overlying a pile of almost neutrally buoyant inert particles. Convection in this system is driven thermally, simulating magma convection above and within a porous cumulate pile. We observe a range of possible convective regimes, enabling us to produce a regime diagram. In addition to modes characterised by convection of the bulk and interstitial fluid, we also observe a series of regimes where the crystal pile is mobilised by fluid motions. These regimes feature saltation and scouring of the crystal pile by convection in the bulk fluid at moderate Rayleigh numbers, and large crystal-rich fountains at high Rayleigh numbers. For even larger Rayleigh numbers the entire crystal pile is mobilised in what we call the snowglobe regime. The observed mobilisation regimes may be applicable to basaltic magma chambers. Plagioclase in basal cumulates crystallised from a dense magma may be a result of crystal mobilisation from a plagioclase-rich roof mush. Compositional convection within such a mush could result in disaggregation, enabling the buoyant plagioclase to be entrained in relatively dense descending liquid plumes and brought to the floor. The phenocryst load in porphyritic lavas is often interpreted as a

  13. The ENEA-IRP thoron calibration facility.

    PubMed

    Calamosca, M; Penzo, S

    2010-10-01

    To check the consistency of a (220)Rn measurement, performed by passive alpha track detector (ATD), the use of an accurate (220)Rn exposure calibration facility is mandatory. The ENEA Radon Service developed a new CR-39 ATD-Tn, coupled to the radon ATD-Rn and, to assess its sensitivity, had to design a small calibration facility, which has been recently modified to improve the spatial homogeneity exposure conditions inside the chamber, to get a continuous monitoring of the (220)Rn concentration and to reduce radon contamination. A better knowledge of the circuit response allowed selecting the best-operating conditions and how to regulate the thoron concentration. The active thoron monitor has been changed to serve as a continuous sampling and measuring device rather than a grab one; particular care has been devoted to assess the (216)Po losses on the device's inner surfaces and to evaluate the chamber transit time correction factor.

  14. Development of a triple beam irradiation facility

    NASA Astrophysics Data System (ADS)

    Hamada, S.; Miwa, Y.; Yamaki, D.; Katano, Y.; Nakazawa, T.; Noda, K.

    1998-10-01

    A triple beam ion irradiation facility has been developed to study the synergistic effects of displacement damage, helium and hydrogen atoms on microstructural changes of materials under irradiation environments simulating a fusion reactor. The system consists of a vacuum chamber and three beamlines, which are connected with each electrostatic accelerator. Samples can be irradiated in the wide temperature range from liquid nitrogen to 1273 K in the chamber by replacing two kinds of sample stages alternatively. An austenitic stainless steel was simultaneously irradiated with triple beam of nickel, helium and hydrogen ions at 573-673 K using this facility and TEM observations were carried out from a cross sectional view normal to the incident surface. It was shown that the number density of dislocation loops decreased in the region where hydrogen and helium were deposited in comparison with ones in the region where only displacement damage was induced to a similar damage level.

  15. The Large Mars Atmosphere Simulation Chamber at the University of Winnipeg

    NASA Astrophysics Data System (ADS)

    Cole, S. B.; Cloutis, E.; Cuddy, M.; Izawa, M. R.; Mann, P.; Craig, M. A.; Pietrasz, V. B.; Squyres, S. W.

    2014-12-01

    We present a new Mars atmosphere simulation chamber (ME: Mars Environment) at the University of Winnipeg Planetary Spectroscopy Facility, available for community use. Our rectangular chamber is 36" wide, 25" high, and 24" deep, with a versatile design capable of accommodating powdered samples, moderately-sized instruments, and geological hand samples and exposing them to a simulated Martian atmosphere. Viewing windows span the upper front and one side, and there are two additional 10"x10" transparent ports on the front, which can be easily opened to install and manipulate apparatus prior to pumping the system down. The windows and ports, which allow for full viewing of the interior, consist of 0.75" thick polycarbonate. The chamber was fabricated from 0.5" thick Al alloy.Our system includes two externally-controlled sample wheels, each of which can hold up to 16 one-inch diameter samples. The samples can be viewed from above through a pair of windows for spectroscopic analysis. In our current configuration, one window above each wheel is ZnS and the other is sapphire, but these can be easily exchanged with other materials to suit various wavelength transmission ranges. One sample wheel is in thermal contact with copper tubing for heating or cooling; the wheel is removable and the tubing manifold can be configured to hold a hand sample for spectroscopic analysis under a controlled temperature and Martian atmospheric pressure.The chamber is large enough to accommodate instruments under consideration for landed missions. A 24-wire electrical pass through enables applications such as powering instruments or monitoring chamber properties (temperatures, atmospheric pressure, etc.).The chamber is available for national and international collaborations and can be used to support a diversity of projects. Our commissioning experiment involves examining the medium-term (several weeks) stability of various water-bearing minerals exposed to Martian surface conditions.

  16. Cryogenic Test Capability at Marshall Space Flight Center's X-ray Cryogenic Test Facility

    NASA Technical Reports Server (NTRS)

    Kegley, Jeffrey; Baker, Mark; Carpenter, Jay; Eng, Ron; Haight, Harlan; Hogue, William; McCracken, Jeff; Siler, Richard; Wright, Ernie

    2006-01-01

    Marshall Space Flight Center's X-ray & Cryogenic Test Facility (XRCF) has been performing sub-liquid nitrogen temperature testing since 1999. Optical wavefront measurement, thermal structural deformation, mechanism functional & calibration, and simple cryo-conditioning tests have been completed. Recent modifications have been made to the facility in support of the James Webb Space Telescope (JWST) program. The chamber's payload envelope and the facility s refrigeration capacity have both been increased. Modifications have also been made to the optical instrumentation area improving access for both the installation and operation of optical instrumentation outside the vacuum chamber. The facility's capabilities, configuration, and performance data will be presented.

  17. Optical processing of bubble chamber photographs.

    PubMed

    Falconer, D G

    1966-09-01

    The processing of bubble chamber photographs has emerged as a major task in the experimental study of sub-atomic decays and interactions. Although electronic computer techniques have proved useful in reconstructing the geometry and ascertaining the kinematics of high-energy events, the scanning and measuring of bubble chamber photographs has remained for the most part unautomated. An alternate approach to the computerization of the scan-measure task is through the newly developed optical computer, a device which accepts input data on photographic film and thus obviates the need for digitizing photographs before processing. The optical computer can aid the scan-measure task by suppressing beam tracks, measuring track widths, and determining scattering angles.

  18. Method of electroforming a rocket chamber

    NASA Technical Reports Server (NTRS)

    Fortini, A. (Inventor)

    1974-01-01

    A transpiration cooled rocket chamber is made by forming a porous metal wall on a suitably shaped mandrel. The porous wall may be made of sintered powdered metal, metal fibers sintered on the mandrel or wires woven onto the mandrel and then sintered to bond the interfaces of the wires. Intersecting annular and longitudinal ribs are then electroformed on the porous wall. An interchamber wall having orifices therein is then electroformed over the annular and longitudinal ribs. Parallel longitudinal ribs are then formed on the outside surface of the interchamber wall after which an annular jacket is electroformed over the parallel ribs to form distribution passages therewith. A feed manifold communicating with the distribution passages may be fabricated and welded to the rocket chamber or the feed manifold may be electroformed in place.

  19. Bubble chamber as a trace chemical detector

    SciTech Connect

    Luo, X.; McCreary, E.I.; Atencio, J.H.; McCown, A.W.; Sander, R.K.

    1998-08-01

    A novel concept for trace chemical analysis in liquid has been demonstrated. The technique utilizes light absorption in a superheated liquid. Although a superheated liquid is thermodynamically unstable, a high degree of superheating can be dynamically achieved for a short period of time. During this time the superheated liquid is extremely sensitive to boiling at nucleation sites produced by energy deposition. Observation of bubbles in the superheated liquid in some sense provides amplification of the initial energy deposition. Bubble chambers containing superheated liquids have been used to detect energetic particles; now a bubble chamber is used to detect a trace chemical in superheated liquid propane by observing bubble formation initiated by optical absorption. Crystal violet is used as a test case and can be detected at the subpart-per-10{sup 12} level by using a Nd:YAG laser. The mechanism for bubble formation and ideas for further improvement are discussed. {copyright} 1998 Optical Society of America

  20. Bubble chamber as a trace chemical detector.

    PubMed

    Luo, X; McCreary, E I; Atencio, J H; McCown, A W; Sander, R K

    1998-08-20

    A novel concept for trace chemical analysis in liquids has been demonstrated. The technique utilizes light absorption in a superheated liquid. Although a superheated liquid is thermodynamically unstable, a high degree of superheating can be dynamically achieved for a short period of time. During this time the superheated liquid is extremely sensitive to boiling at nucleation sites produced by energy deposition. Observation of bubbles in the superheated liquid in some sense provides amplification of the initial energy deposition. Bubble chambers containing superheated liquids have been used to detect energetic particles; now a bubble chamber is used to detect a trace chemical in superheated liquid propane by observing bubble formation initiated by optical absorption. Crystal violet is used as a test case and can be detected at the subpart-per-10(12) level by using a Nd:YAG laser. The mechanism for bubble formation and ideas for further improvement are discussed.

  1. Space station auxiliary thrust chamber technology

    NASA Technical Reports Server (NTRS)

    Senneff, J. M.

    1987-01-01

    A program to design, fabricate, and test a 50 lb sub f (222 N) thruster was undertaken to demonstrate the applicability of the reverse flow concept as an item of auxillary propulsion for the Space Station. The thruster was to operate at a mixture ratio (O/F) of 4, be capable of operating for 2 million lb sub f-seconds (8.896 million N-seconds) impulse with a chamber pressure of 75 psia (52N/sq cm) and a nozzle area ratio of 40. A successful demonstration of an (0/F) of 4 thruster, was followed by the design objective of operating at (O/F) of 8. The demonstration of this thruster resulted in the order of and additional (O/F) of 8 thruster chamber under the present NAS 3-24883 contract. The effort to fabricate and test the second (0/F) of 8 thruster is documented.

  2. Combustion interaction with radiation-cooled chambers

    NASA Technical Reports Server (NTRS)

    Rosenberg, S. D.; Jassowski, D. M.; Barlow, R.; Lucht, R.; Mccarty, K.

    1990-01-01

    Over 15 hours of thruster operation at temperatures between 1916 and 2246 C without failure or erosion has been demonstrated using iridium-coated rhenium chamber materials with nitrogen tetroxide/monomethylhydrazine propellants operating over a mixture ratio range of 1.60-2.05. Research is now under way to provide a basic understanding of the mechanisms which make high-temperature operation possible and to extend the capability to a wider range of conditions, including other propellant combinations and chamber materials. Techniques have been demonstrated for studying surface fracture phenomena. These include surface Raman and Auger for study of oxide formation, surface Raman and X-ray diffraction to determine the oxide phase, Auger to study oxide stoichiometry, and sputter Auger to study interdiffusion of alloy species.

  3. Test facilities for high power electric propulsion

    NASA Technical Reports Server (NTRS)

    Sovey, James S.; Vetrone, Robert H.; Grisnik, Stanley P.; Myers, Roger M.; Parkes, James E.

    1991-01-01

    Electric propulsion has applications for orbit raising, maneuvering of large space systems, and interplanetary missions. These missions involve propulsion power levels from tenths to tens of megawatts, depending upon the application. General facility requirements for testing high power electric propulsion at the component and thrust systems level are defined. The characteristics and pumping capabilities of many large vacuum chambers in the United States are reviewed and compared with the requirements for high power electric propulsion testing.

  4. High pressure hydrogen time projection chamber

    SciTech Connect

    Goulianos, K.

    1983-01-01

    We describe a high pressure hydrogen gas time projection chamber which consists of two cylindrical drift regions each 45 cm in diameter and 75 cm long. Typically, at 15 atm of H/sub 2/ with 2 kV/cm drift field and 7 kV on the 35..mu.. sense wires, the drift velocity is about 0.5 cm/..mu..sec and the spatial resolution +-200..mu...

  5. Compact Vapor Chamber Cools Critical Components

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Advancements in the production of proton exchange membrane fuel cells have NASA considering their use as a power source for spacecraft and robots in future space missions. With SBIR funding from Glenn Research Center, Lancaster, Pennsylvania-based Thermacore Inc. developed strong, lightweight titanium vapor chambers to keep the fuel cells operating at optimum temperatures. The company is now selling the technology for cooling electronic components.

  6. Comment on 'Proton beam monitor chamber calibration'.

    PubMed

    Palmans, Hugo; Vatnitsky, Stanislav M

    2016-09-01

    We comment on a recent article (Gomà et al 2014 Phys. Med. Biol. 59 4961-71) which compares different routes of reference dosimetry for the energy dependent beam monitor calibration in scanned proton beams. In this article, a 3% discrepancy is reported between a Faraday cup and a plane-parallel ionization chamber in the experimental determination of the number of protons per monitor unit. It is further claimed that similar discrepancies between calorimetry and ionization chamber based dosimetry indicate that [Formula: see text]-values tabulated for proton beams in IAEA TRS-398 might be overestimated. In this commentary we show, however, that this supporting argument misrepresents the evidence in the literature and that the results presented, together with published data, rather confirm that there exist unresolved problems with Faraday cup dosimetry. We also show that the comparison in terms of the number of protons gives a biased view on the uncertainty estimates for both detectors while the quantity of interest is absorbed dose to water or dose-area-product to water, even if a beam monitor is calibrated in terms of the number of protons. Gomà et al (2014 Phys. Med. Biol. 59 4961-71) also report on the discrepancy between cylindrical and plane-parallel ionization chambers and confirm experimentally that in the presence of a depth dose gradient, theoretical values of the effective point of measurement, or alternatively a gradient correction factor, account for the discrepancy. We believe this does not point to an error or shortcoming of IAEA TRS-398, which prescribes taking the centre of cylindrical ionization chambers as reference point, since it recommends reference dosimetry to be performed in the absence of a depth dose gradient. But these observations reveal that important aspects of beam monitor calibration in scanned proton beams are not addressed in IAEA TRS-398 given that those types of beams were not widely implemented at the time of its publication

  7. CFD Code Survey for Thrust Chamber Application

    NASA Technical Reports Server (NTRS)

    Gross, Klaus W.

    1990-01-01

    In the quest fo find analytical reference codes, responses from a questionnaire are presented which portray the current computational fluid dynamics (CFD) program status and capability at various organizations, characterizing liquid rocket thrust chamber flow fields. Sample cases are identified to examine the ability, operational condition, and accuracy of the codes. To select the best suited programs for accelerated improvements, evaluation criteria are being proposed.

  8. Magma chamber dynamics and Vesuvius eruption forecasting

    NASA Astrophysics Data System (ADS)

    Dobran, F.

    2003-04-01

    Magma is continuously or periodically refilling an active volcano and its eruption depends on the mechanical, fluid, thermal, and chemical aspects of the magma storage region and its surroundings. A cyclically loaded and unloaded system can fail from a weakness in the system or its surroundings, and the fluctuating stresses can produce system failures at stress levels that are considerably below the yield strength of the material. Magma in a fractured rock system within a volcano is unstable and propagates toward the surface with the rate depending on the state of the system defined by the inertia, gravity, friction, and permeability parameters of magma and its source region. Cyclic loading and unloading of magma from a reservoir caused by small- or medium-scale eruptions of Vesuvius can produce catastrophic plinian eruptions because of the structural failure of the system and the quiescent periods between these eruptions increase with time until the next eruption cycle which will be plinian or subplinian and will occur with a very high probability this century. Such a system behavior is predicted by a Global Volcanic Simulator of Vesuvius developed for simulating different eruption scenarios for the purpose of urban planning the territory, reducing the number of people residing too close to the cone of the volcano, and providing safety to those beyond about 5 km radius of the crater. The magma chamber model of the simulator employs a thermomechanical model that includes magma inflow and outflow from the chamber, heat and mass transfer between the chamber and its surroundings, and thermoelastoplastic deformation of the shell surrounding the magma source region. These magma chamber, magma ascent, and pyroclastic dispersion models and Vesuvius eruption forecasting are described in Dobran, F., VOLCANIC PROCESSES, Kluwer Academic/Plenum Publishers, 2001, 590 pp.

  9. Basaltic injections into floored silicic magma chambers

    NASA Astrophysics Data System (ADS)

    Wiebe, R. A.

    Recent studies have provided compelling evidence that many large accumulations of silicic volcanic rocks erupted from long-lasting, floored chambers of silicic magma that were repeatedly injected by basaltic magma. These basaltic infusions are commonly thought to play an important role in the evolution of the silicic systems: they have been proposed as a cause for explosive silicic eruptions [Sparks and Sigurdsson, 1977], compositional variation in ash-flow sheets [Smith, 1979], mafic magmatic inclusions in silicic volcanic rocks [Bacon, 1986], and mixing of mafic and silicic magmas [Anderson, 1976; Eichelberger, 1978]. If, as seems likely, floored silicic magma chambers have frequently been invaded by basalt, then plutonic bodies should provide records of these events. Although plutonic evidence for mixing and commingling of mafic and silicic magmas has been recognized for many years, it has been established only recently that some intrusive complex originated through multiple basaltic injections into floored chambers of silicic magma [e.g., Wiebe, 1974; Michael, 1991; Chapman and Rhodes, 1992].

  10. SONTRAC: A solar neutron track chamber detector

    NASA Technical Reports Server (NTRS)

    Frye, G. M., Jr.; Jenkins, T. L.; Owens, A.

    1985-01-01

    The recent detection on the solar maximum mission (SMM) satellite of high energy neutrons emitted during large solar flares has provided renewed incentive to design a neutron detector which has the sensitivity, energy resolution, and time resolution to measure the neutron time and energy spectra with sufficient precision to improve our understanding of the basic flare processes. Over the past two decades a variety of neutron detectors has been flown to measure the atmospheric neutron intensity above 10 MeV and to search for solar neutrons. The SONTRAC (Solar Neutron Track Chamber) detector, a new type of neutron detector which utilizes n-p scattering and has a sensitivity 1-3 orders of magnitude greater than previous instruments in the 20-200 MeV range is described. The energy resolution is 1% for neutron kinetic energy, T sub n 50 MeV. When used with a coded aperture mask at 50 m (as would be possible on the space station) an angular resolution of approx. 4 arc sec could be achieved, thereby locating the sites of high energy nuclear interactions with an angular precision comparable to the existing x-ray experiments on SMM. The scintillation chamber is investigated as a track chamber for high energy physics, either by using arrays of scintillating optical fibers or by optical imaging of particle trajectories in a block of scintillator.

  11. Sperm Cell Dynamics in Shallow Chambers

    NASA Astrophysics Data System (ADS)

    Condat, Carlos; Marconi, Veronica; Guidobaldi, Alejandro; Giojalas, Laura; Silhanek, Alejandro; Jeyaram, Yogesh; Moshchalkov, Victor

    2015-03-01

    Self-propelled microorganisms are attracted to surfaces. This makes their dynamic behavior in restricted geometries very different from that observed in the bulk. Here we analyze the motion of spermatozoids confined to shallow chambers, investigating the nature of the cell trajectories and their accumulation near the side boundaries. Observed cell trajectories are composed of a succession of quasi-circular and quasi-linear segments. This suggests that the cells follow a path of intermittent trappings near the top and down surfaces separated by stretches of quasi-free motion near the center of the gap. Use of microstructured petal-shaped edges limits accumulation near the borders and contributes to increase the concentration in the chamber interior. System stabilization occurs over times of the order of minutes, which agrees well with a theoretical estimate that assumes that the cell mean-square displacement is largely due to the quasi-linear segments. Pure quasi-circular trajectories would require several hours to stabilize. Our estimates also indicate that stabilization proceeds 2.5 times faster in the rosette geometries than in the smooth-edged chambers, which is another practical reason to prefer the former.

  12. 23. PHOTOCOPY OF PHOTOGRAPH. View west of Tropic Chamber refrigeration ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. PHOTOCOPY OF PHOTOGRAPH. View west of Tropic Chamber refrigeration equipment, ca. 1955. (Source: NRDEC). - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  13. 1. View southeast of Climatic Chambers Building from roof of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View southeast of Climatic Chambers Building from roof of Research Building. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  14. 7. Detail view west of Arctic Chamber wind tunnel shell ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail view west of Arctic Chamber wind tunnel shell (typical) in east elevation. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  15. 21. PHOTOCOPY OF PHOTOGRAPH. view north of Tropic Chamber, ca. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. PHOTOCOPY OF PHOTOGRAPH. view north of Tropic Chamber, ca. 1955. (Source: NRDEC). - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  16. EXTERIOR VIEW OF AIRLOCK FOR ALTITUDE CHAMBER R, FACING SOUTHEAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR VIEW OF AIRLOCK FOR ALTITUDE CHAMBER R, FACING SOUTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  17. DETAIL OF DOMED BOTTOM, ALTITUDE CHAMBER R, FACING EAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF DOMED BOTTOM, ALTITUDE CHAMBER R, FACING EAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  18. VIEW OF PUMP ROOM FOR ALTITUDE CHAMBERS, FACING SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF PUMP ROOM FOR ALTITUDE CHAMBERS, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  19. INTERIOR OF AIRLOCK FROM INTERIOR OF ALTITUDE CHAMBER R, FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF AIRLOCK FROM INTERIOR OF ALTITUDE CHAMBER R, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  20. DETAIL OF THE INTERIOR OF THE DOMED LID, ALTITUDE CHAMBER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF THE INTERIOR OF THE DOMED LID, ALTITUDE CHAMBER R, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  1. DETAIL OF PLATFORM SUPPORT BRACKET, ALTITUDE CHAMBER L, FACING NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF PLATFORM SUPPORT BRACKET, ALTITUDE CHAMBER L, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  2. DETAIL OF WALLMOUNTED STAIRS ON INTERIOR OF ALTITUDE CHAMBER L, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF WALL-MOUNTED STAIRS ON INTERIOR OF ALTITUDE CHAMBER L, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  3. EXTERIOR OF ALTITUDE CHAMBERS R (TO LEFT) AND L (TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OF ALTITUDE CHAMBERS R (TO LEFT) AND L (TO RIGHT), FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  4. EXTERIOR OF ALTITUDE CHAMBERS R (TO LEFT) AND L (TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OF ALTITUDE CHAMBERS R (TO LEFT) AND L (TO RIGHT), FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  5. EXTERIOR AND INTERIOR VIEW OF AIRLOCK FOR ALTITUDE CHAMBER R, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR AND INTERIOR VIEW OF AIRLOCK FOR ALTITUDE CHAMBER R, FACING SOUTH - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  6. BOTTOM LEVEL OF ALTITUDE CHAMBER L, FACING SOUTHWEST Cape ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BOTTOM LEVEL OF ALTITUDE CHAMBER L, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  7. UPPER HALF OF THE INTERIOR OF ALTITUDE CHAMBER R, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    UPPER HALF OF THE INTERIOR OF ALTITUDE CHAMBER R, LOOKING UP FROM BOTTOM LEVEL, FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  8. INTERIOR OF ALTITUDE CHAMBER R, LOOKING DOWN FROM AIRLOCK, FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF ALTITUDE CHAMBER R, LOOKING DOWN FROM AIRLOCK, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  9. VIEW OF THE CONTROL ROOM FOR THE ALTITUDE CHAMBERS, FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF THE CONTROL ROOM FOR THE ALTITUDE CHAMBERS, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  10. DETAIL OF THE EXTERIOR OF THE DOMED LID, ALTITUDE CHAMBER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF THE EXTERIOR OF THE DOMED LID, ALTITUDE CHAMBER R, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  11. DETAIL OF REPRESSURIZATION AIR PIPE, ALTITUDE CHAMBER L, FACING SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF RE-PRESSURIZATION AIR PIPE, ALTITUDE CHAMBER L, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  12. INTERIOR OF ALTITUDE CHAMBER L FROM TOP LEVEL OF ACCESS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF ALTITUDE CHAMBER L FROM TOP LEVEL OF ACCESS PLATFORMS, FACING WEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  13. DETAIL OF DOMED BOTTOM, ALTITUDE CHAMBER L, FACING NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF DOMED BOTTOM, ALTITUDE CHAMBER L, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  14. LOWER HALF OF THE INTERIOR OF ALTITUDE CHAMBER R, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LOWER HALF OF THE INTERIOR OF ALTITUDE CHAMBER R, LOOKING UP FROM BOTTOM LEVEL, FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  15. INTERIOR OF ALTITUDE CHAMBER L, LOOKING UP FROM BOTTOM LEVEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF ALTITUDE CHAMBER L, LOOKING UP FROM BOTTOM LEVEL OF INTERNAL PLATFORMS, FACING EAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  16. 30 CFR 57.7807 - Flushing the combustion chamber.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and Rotary Jet Piercing Rotary Jet Piercing-Surface Only § 57.7807 Flushing the combustion chamber. The combustion chamber of a jet drill stem which has been sitting unoperated in a drill hole shall...

  17. 30 CFR 57.7807 - Flushing the combustion chamber.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Rotary Jet Piercing Rotary Jet Piercing-Surface Only § 57.7807 Flushing the combustion chamber. The combustion chamber of a jet drill stem which has been sitting unoperated in a drill hole shall...

  18. 30 CFR 56.7807 - Flushing the combustion chamber.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Rotary Jet Piercing Rotary Jet Piercing § 56.7807 Flushing the combustion chamber. The combustion chamber of a jet drill stem which has been sitting unoperated in a drill hole shall be flushed with...

  19. 30 CFR 56.7807 - Flushing the combustion chamber.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Rotary Jet Piercing Rotary Jet Piercing § 56.7807 Flushing the combustion chamber. The combustion chamber of a jet drill stem which has been sitting unoperated in a drill hole shall be flushed with...

  20. DETAIL OF VACUUM PIPE OPENING WITHIN ALTITUDE CHAMBER R, FACING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF VACUUM PIPE OPENING WITHIN ALTITUDE CHAMBER R, FACING SOUTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  1. Andy Chambers Homestead, Chicken Coop, Saddle Shop, and Granary, looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Andy Chambers Homestead, Chicken Coop, Saddle Shop, and Granary, looking northeast - Andy Chambers Homestead, 0.4 mile south of Antelope Flats Road on the east side of Mormon Row Road, Kelly, Teton County, WY

  2. Chamber Design For Slow Nucleation Protein Crystal Growth

    NASA Technical Reports Server (NTRS)

    Pusey, Marc Lee

    1995-01-01

    Multiple-chamber dialysis apparatus grows protein crystals on Earth or in microgravity with minimum of intervention by technician. Use of multiple chambers provides gradation of nucleation and growth rates.

  3. 11. Second floor, northwest chamber, south wall. Former passage to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Second floor, northwest chamber, south wall. Former passage to southwest chamber (door blocked off on far side) on left; closet on right. - Conner Homestead, House, Epping Road (State Route 101), Exeter, Rockingham County, NH

  4. CONTAINMENT SYSTEM, SPRAY CHAMBER, LOOKING NORTH WITH MIST COOLING MOLTEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CONTAINMENT SYSTEM, SPRAY CHAMBER, LOOKING NORTH WITH MIST COOLING MOLTEN STEEL SLABS AS THEY PROGRESS THROUGH THIS CHAMBER. - U.S. Steel, Fairfield Works, Continuous Caster, Fairfield, Jefferson County, AL

  5. DESIGN, CONSTRUCTION, AND EVALUATION OF A CHAMBER FOR AEROBIOLOGY

    EPA Science Inventory

    A chamber was designed and constructed for aeromicrobiology applications. An ultraviolet (UV) radiation source was incorporated to sterilize the chamber between trials. Twelve bacterial species originally isolated from air samples and obtained from the American Type Culture Colle...

  6. Utilizing Chamber Data for Developing and Validating Climate Change Models

    NASA Technical Reports Server (NTRS)

    Monje, Oscar

    2012-01-01

    Controlled environment chambers (e.g. growth chambers, SPAR chambers, or open-top chambers) are useful for measuring plant ecosystem responses to climatic variables and CO2 that affect plant water relations. However, data from chambers was found to overestimate responses of C fluxes to CO2 enrichment. Chamber data may be confounded by numerous artifacts (e.g. sidelighting, edge effects, increased temperature and VPD, etc) and this limits what can be measured accurately. Chambers can be used to measure canopy level energy balance under controlled conditions and plant transpiration responses to CO2 concentration can be elucidated. However, these measurements cannot be used directly in model development or validation. The response of stomatal conductance to CO2 will be the same as in the field, but the measured response must be recalculated in such a manner to account for differences in aerodynamic conductance, temperature and VPD between the chamber and the field.

  7. 58. Interior view, porch chamber, south elevation. The room door ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    58. Interior view, porch chamber, south elevation. The room door is open allowing a view into the study chamber. - John Bartram House & Garden, House, 54th Street & Lindbergh Boulevard, Philadelphia, Philadelphia County, PA

  8. 19. View northwest of Tropic Chamber reciprocal compressors (typical), in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. View northwest of Tropic Chamber reciprocal compressors (typical), in machine area. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  9. 16. View northwest of Arctic Chamber Worthington centrifugal compressor and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. View northwest of Arctic Chamber Worthington centrifugal compressor and control panel, in machine area. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  10. 18. View north of Tropic Chamber Worthington centrifugal compressor and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. View north of Tropic Chamber Worthington centrifugal compressor and control panel, in machine area. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  11. 17. View northwest of Tropic Chamber refrigeration equipment, in machine ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. View northwest of Tropic Chamber refrigeration equipment, in machine area. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  12. 51. UPPER CHAMBER OF BISCUIT KILN No. 4, FROM THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. UPPER CHAMBER OF BISCUIT KILN No. 4, FROM THE SECOND FLOOR. ALL BRICK KILNS AT THE MORAVIAN POTTERY AND TILE WORKS HAD TWO CHAMBERS. WARE WAS STACKED IN THE LOWER CHAMBERS FOR FIRING AND THE UPPER CHAMBERS PROVIDED ACCESS TO FLUES AND DAMPERS FROM THE SECOND FLOOR. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

  13. Herds of methane chambers grazing bubbles

    NASA Astrophysics Data System (ADS)

    Grinham, Alistair; Dunbabin, Matthew

    2014-05-01

    Water to air methane emissions from freshwater reservoirs can be dominated by sediment bubbling (ebullitive) events. Previous work to quantify methane bubbling from a number of Australian sub-tropical reservoirs has shown that this can contribute as much as 95% of total emissions. These bubbling events are controlled by a variety of different factors including water depth, surface and internal waves, wind seiching, atmospheric pressure changes and water levels changes. Key to quantifying the magnitude of this emission pathway is estimating both the bubbling rate as well as the areal extent of bubbling. Both bubbling rate and areal extent are seldom constant and require persistent monitoring over extended time periods before true estimates can be generated. In this paper we present a novel system for persistent monitoring of both bubbling rate and areal extent using multiple robotic surface chambers and adaptive sampling (grazing) algorithms to automate the quantification process. Individual chambers are self-propelled and guided and communicate between each other without the need for supervised control. They can maintain station at a sampling site for a desired incubation period and continuously monitor, record and report fluxes during the incubation. To exploit the methane sensor detection capabilities, the chamber can be automatically lowered to decrease the head-space and increase concentration. The grazing algorithms assign a hierarchical order to chambers within a preselected zone. Chambers then converge on the individual recording the highest 15 minute bubbling rate. Individuals maintain a specified distance apart from each other during each sampling period before all individuals are then required to move to different locations based on a sampling algorithm (systematic or adaptive) exploiting prior measurements. This system has been field tested on a large-scale subtropical reservoir, Little Nerang Dam, and over monthly timescales. Using this technique

  14. Layer Formation in Convective Magma Chambers

    NASA Astrophysics Data System (ADS)

    Höink, T.; Schmalzl, J.; Hansen, U.

    2004-12-01

    The dynamics of a convective magma chamber is crucially influenced by the competetion between sedimentation and convective suspension of crystals. Crystal settling combined with the crystal's density contribution is a possible mechanism leading to differentiation and layer formation. Here we address the question whether crystals can remain suspended or whether they are able to dynamically form a layered structure within the convective lifetime of a magma chamber. We employ an existing numerical method that, by means of a finite volume scheme, discretizes the equations for thermally driven convection in an infinite Prandtl-number Boussinesq fluid in Cartesian geometry. We implement a newly developed settling algorithm for the numerical study of finite-sized-particle settling in a non-dilute convective suspension. Our approach considers a consistent settling velocity and the density contribution due to particle mass. The buoyancy ratio B, which is the ratio of the density variation due to crystal mass to the thermal density variation, is varied for five different Rayleigh numbers, covering a range of four orders of magnitude. We find B to be a critical parameter and its critical value to depend on the Rayleigh number. For subcritical values we observe that the presence of a crystal phase reduces convective vigor and most crystals stay suspended. When a critical buoyancy ratio is exceeded, the presence of crystals can significantly alter convective motion. For all investigated Rayleigh numbers we find a critical buoyancy ratio, above which layering can be achieved from an initially unstratified fluid. Most of the crystal mass collects in the dynamically created bottom layer, even for cases where the average settling velocity is three orders of magnitude smaller than the root mean square convective velocity. The time it takes a crystal to travel across the height of the cell with the full settling velocity in the absence of a thermal gradient defines the settling

  15. Recent Improvements to the Acoustical Testing Laboratory at the NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Podboy, Devin M.; Mirecki, Julius H.; Walker, Bruce E.; Sutliff, Daniel L.

    2014-01-01

    The Acoustical Testing Laboratory (ATL) consists of a 27- by 23- by 20-ft (height) convertible hemi/anechoic chamber and separate sound-attenuating test support enclosure. Absorptive fiberglass wedges in the test chamber provide an anechoic environment down to 100 Hz. A spring-isolated floor system affords vibration isolation above 3 Hz. These specifications, along with very low design background levels, enable the acquisition of accurate and repeatable acoustical measurements on test articles that produce very low sound pressures. Removable floor wedges allow the test chamber to operate in either a hemi-anechoic or anechoic configuration, depending on the size of the test article and the specific test being conducted. The test support enclosure functions as a control room during normal operations. Recently improvements were accomplished in support of continued usage of the ATL by NASA programs including an analysis of the ultra-sonic characteristics. A 3-D traverse system inside the chamber was utilized for acquiring acoustic data for these tests. The traverse system drives a linear array of 13, 1/4 in.-microphones spaced 3 in. apart (36 in. span). An updated data acquisition system was also incorporated into the facility.

  16. Recent Improvements to the Acoustical Testing Laboratory at the NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Podboy, Devin M.; Mirecki, Julius H.; Walker, Bruce E.; Sutliff, Daniel L.

    2014-01-01

    The Acoustical Testing Laboratory (ATL) consists of a 27 by 23 by 20 ft (height) convertible hemi/anechoic chamber and separate sound-attenuating test support enclosure. Absorptive fiberglass wedges in the test chamber provide an anechoic environment down to 100 Hz. A spring-isolated floor system affords vibration isolation above 3 Hz. These specifications, along with very low design background levels, enable the acquisition of accurate and repeatable acoustical measurements on test articles that produce very low sound pressures. Removable floor wedges allow the test chamber to operate in either a hemi-anechoic or anechoic configuration, depending on the size of the test article and the specific test being conducted. The test support enclosure functions as a control room during normal operations. Recently improvements were accomplished in support of continued usage of the ATL by NASA programs including an analysis of the ultra-sonic characteristics. A 3 dimensional traverse system inside the chamber was utilized for acquiring acoustic data for these tests. The traverse system drives a linear array of 13, 1/4"-microphones spaced 3" apart (36" span). An updated data acquisition system was also incorporated into the facility.

  17. Characterization of a homemade ionization chamber for radiotherapy beams.

    PubMed

    Neves, Lucio P; Perini, Ana P; dos Santos, Gelson P; Xavier, Marcos; Khoury, Helen J; Caldas, Linda V E

    2012-07-01

    A homemade cylindrical ionization chamber was studied for routine use in therapy beams of (60)Co and X-rays. Several characterization tests were performed: leakage current, saturation, ion collection efficiency, polarity effect, stability, stabilization time, chamber orientation and energy dependence. All results obtained were within international recommendations. Therefore the homemade ionization chamber presents usefulness for routine dosimetric procedures in radiotherapy beams.

  18. 7 CFR 58.423 - Cheese vacuumizing chamber.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and...

  19. 7 CFR 58.423 - Cheese vacuumizing chamber.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and...

  20. 7 CFR 58.423 - Cheese vacuumizing chamber.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and...

  1. 7 CFR 58.423 - Cheese vacuumizing chamber.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and...

  2. 7 CFR 58.423 - Cheese vacuumizing chamber.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and...

  3. VIEW OF THE TOPS OF ALTITUDE CHAMBER R (TO LEFT) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF THE TOPS OF ALTITUDE CHAMBER R (TO LEFT) AND ALTITUDE CHAMBER L (TO RIGHT) FROM THE 42’-0” LEVEL OF ACCESS PLATFORMS, FACING NORTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  4. Engineering analyses of large precision cathode strip chambers for GEM

    SciTech Connect

    Horvath, J.A.; Belser, F.C.; Pratuch, S.M.; Wuest, C.R.; Mitselmakher, G.; Gordeev, A.; Johnson, C.V. |; Polychronakos, V.A.; Golutvin, I.A.

    1993-10-21

    Structural analyses of large precision cathode strip chambers performed up to the date of this publication are documented. Mechanical property data for typical chamber materials are included. This information, originally intended to be an appendix to the {open_quotes}CSC Structural Design Bible,{close_quotes} is presented as a guide for future designers of large chambers.

  5. Cloud Chamber Activities for the High School Classroom.

    ERIC Educational Resources Information Center

    Perry, John Timothy; Sankey, Mary Ann

    1995-01-01

    Presents the idea that cloud chambers can be used by students as an experimental tool enabling them to conduct their own investigations on radiation. Provides detail regarding the construction of a cloud chamber and suggestions for student assignments that involve the cloud chamber. (DDR)

  6. 21 CFR 884.5225 - Abdominal decompression chamber.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Abdominal decompression chamber. 884.5225 Section... Devices § 884.5225 Abdominal decompression chamber. (a) Identification. An abdominal decompression chamber is a hoodlike device used to reduce pressure on the pregnant patient's abdomen for the relief...

  7. 46 CFR 197.332 - PVHO-Decompression chambers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false PVHO-Decompression chambers. 197.332 Section 197.332... STANDARDS GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.332 PVHO—Decompression chambers. Each decompression chamber must— (a) Meet the requirements of § 197.328; (b) Have internal...

  8. Detail of interior of compressed air chamber showing top of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of interior of compressed air chamber showing top of working chamber and tie rods that strengthen the outer shell plates of the compression chamber. - Sub Marine Explorer, Located along the beach of Isla San Telmo, Pearl Islands, Isla San Telmo, Former Panama Canal Zone, CZ

  9. Coking oven with horizontal chambers for producing coke

    SciTech Connect

    Jakobi, W.

    1984-06-26

    In a coking oven with a horizontal chamber the chamber is provided with a filling hole having a cylindrical portion with the diameter D and a reduced portion downwardly extending therefrom into the chamber over the height H. The ratio between D and H 1.5.

  10. Semiclosed-circuit atmosphere control in a portable recompression chamber

    NASA Technical Reports Server (NTRS)

    Riegel, P. S.; Caudy, D. W.

    1972-01-01

    A small portable recompression chamber is described that can be used both to treat a diver for decompression sickness or to transport him to a larger chamber complex. The device can be operated in either open circuit or semiclosed circuit atmospheres, permits two way conversation between patient and attendant, and uses an air injector for circulation of the chamber atmosphere.

  11. The Biological Flight Research Facility

    NASA Technical Reports Server (NTRS)

    Johnson, Catherine C.

    1993-01-01

    NASA Ames Research Center (ARC) is building a research facility, the Biological Flight Research Facility (BFRF), to meet the needs of life scientists to study the long-term effects of variable gravity on living systems. The facility will be housed on Space Station Freedom and is anticipated to operate for the lifetime of the station, approximately thirty years. It will allow plant and animal biologists to study the role of gravity, or its absence, at varying gravity intensities for varying periods of time and with various organisms. The principal difference between current Spacelab missions and those on Space Station Freedom, other than length of mission, will be the capability to perform on-orbit science procedures and the capability to simulate earth gravity. Initially the facility will house plants and rodents in habitats which can be maintained at microgravity or can be placed on a 2.5 meter diameter centrifuge. However, the facility is also being designed to accommodate future habitats for small primates, avian, and aquatic specimens. The centrifuge will provide 1 g for controls and will also be able to provide gravity from 0.01 to 2.0 g for threshold gravity studies as well as hypergravity studies. Included in the facility are a service unit for providing clean chambers for the specimens and a glovebox for manipulating the plant and animal specimens and for performing experimental protocols. The BFRF will provide the means to conduct basic experiments to gain an understanding of the effects of microgravity on the structure and function of plants and animals, as well as investigate the role of gravity as a potential countermeasure for the physiological changes observed in microgravity.

  12. CFD-CAA Coupled Calculations of a Tandem Cylinder Configuration to Assess Facility Installation Effects

    NASA Technical Reports Server (NTRS)

    Redonnet, Stephane; Lockard, David P.; Khorrami, Mehdi R.; Choudhari, Meelan M.

    2011-01-01

    This paper presents a numerical assessment of acoustic installation effects in the tandem cylinder (TC) experiments conducted in the NASA Langley Quiet Flow Facility (QFF), an open-jet, anechoic wind tunnel. Calculations that couple the Computational Fluid Dynamics (CFD) and Computational Aeroacoustics (CAA) of the TC configuration within the QFF are conducted using the CFD simulation results previously obtained at NASA LaRC. The coupled simulations enable the assessment of installation effects associated with several specific features in the QFF facility that may have impacted the measured acoustic signature during the experiment. The CFD-CAA coupling is based on CFD data along a suitably chosen surface, and employs a technique that was recently improved to account for installed configurations involving acoustic backscatter into the CFD domain. First, a CFD-CAA calculation is conducted for an isolated TC configuration to assess the coupling approach, as well as to generate a reference solution for subsequent assessments of QFF installation effects. Direct comparisons between the CFD-CAA calculations associated with the various installed configurations allow the assessment of the effects of each component (nozzle, collector, etc.) or feature (confined vs. free jet flow, etc.) characterizing the NASA LaRC QFF facility.

  13. Stormwater treatment at critical areas: The multi-chambered treatment train (MCTT). Final report

    SciTech Connect

    Pitt, R.; Peterson, B.; Barron, P.; Ayyoubi, A.; Clark, S.

    1999-02-01

    Past studies have identified urban runoff as a major contributor to the degradation of many urban streams and rivers. The objective of this research was to characterize typical toxicant concentrations in stormwater, and investigate the effectiveness of treatment processes to control the toxicants. A prototype treatment device (the multi-chambered treatment train, or MCTT) was tested during the final phase of this project. The MCTT is an underground device that has three main chambers: an initial grit chamber for trapping of the largest sediment and release of most volatile materials; a main setting chamber (providing initial aeration and sorbent pillows) for the trapping of fine sediment and associated toxicants and floating hydrocarbons; and a sand and peat mixed media filter (sorption-ion exchange) unit for the monitoring period. During monitoring of 13 storms at a parking facility, the pilot-scale MCTT was found to have the following overall median reduction rates: 96% for total toxicity, 98% for filtered toxicity, 83% for SS, 60% for COD, 40% for turbidity, 100% for lead, 91% for zinc, 100% for n-Nitro-di-n-proplamine, 100% for pyrene, and 99% for bis (2-ethyl-hexyl) phthalate. the color was increased by about 50% due to staining from the peat and the pH decreased by about one-half pH unit, also from the peat media. Ammonia nitrogen was increased by several times, and nitrate nitrogen had low reductions (about 14%).

  14. Drift time spectrum and gas monitoring in the ATLAS Muon Spectrometer precision chambers

    NASA Astrophysics Data System (ADS)

    Levin, Daniel S.; Amram, Nir; Ball, Robert; ben Moshe, Meny; Benhammou, Yan; Chapman, John W.; Dai, Tiesheng; Diehl, Edward B.; Etzion, Erez; Ferretti, Claudio; Goldfarb, Steven; Gregory, Jeffery; Kiesel, Mike; McKee, Shawn; Thun, Rudi; Weaverdyck, Curtis; Wilson, Alan; Zhao, Zhengguo; Zhou, Bing

    2008-04-01

    The ATLAS Muon Spectrometer incorporates 354 000 drift tubes assembled into 1200 Monitored Drift Tube (MDT) precision chambers, with a total gas volume of 723 m3. This MDT gas, Ar 93% and CO2 7% at 3 bar, is cycled through the spectrometer at a rate of one total detector volume per day. Achieving the 80 μm drift tube design resolution requires stringent gas quality control as a fundamental component of the MDT calibration program. We report on the design, deployment and performance of a dedicated MDT mini-chamber conceived for continuous monitoring and drift time calibration of the ATLAS MDT operating gas. This chamber enables measurement of the drift spectra from which gas properties relevant to MDT calibrations and stable operating conditions are determined. Located in the ATLAS gas facility at CERN, the mini-chamber produces hourly drift spectra which are automatically analyzed. Results are published online and disseminated to the ATLAS muon system conditions and calibration databases in real time.

  15. Proposal of a growth chamber for growing Super-Dwarf Rice in Space Agriculture

    NASA Astrophysics Data System (ADS)

    Hirai, Hiroaki; Kitaya, Yoshiaki; Tsukamoto, Koya; Yamashita, Youichirou; Hirai, Takehiro

    Space agriculture needs to be considered to supply food for space crew who stay in space over an extended time period. So far crops such as wheat, onion, oat, pea and lettuce grew to explore the possibility of space agriculture. Although rice is a staple food for most of the world, research on rice cultivation in space has not been done much. Rice grains are nutrient-rich with carbohydrate, protein and dietary fiber. Moreover, rice is a high yield crop and harvested grains have a long shelf life. However, the plant height of standard rice cultivars is relatively long, requiring much space. In addition, rice plants require higher light intensities for greater yield. For these reasons, it is difficult to establish facilities for rice culture in a limited space with a low cost. We propose to employee a super-dwarf cultivar and a small growth chamber with a new type of LEDs. The super-dwarf rice is a short-grain japonica variety and the plant height is approximately 20 cm that is one-fifth as tall as standard cultivars. The LED light used as a light source for this study can provide full spectrum of 380 nm to 750 nm. Air temperature and humidity were controlled by a Peltier device equipped in the chamber. The characteristics of the new type of LEDs and other equipments of the chamber and the ground based performance of super-dwarf rice plants grown in the chamber will be reported.

  16. The U.S. Lab is placed in vacuum chamber for leak test

    NASA Technical Reports Server (NTRS)

    2000-01-01

    With the lid of the three-story vacuum chamber in place, a worker on top checks release of the cables. Inside the chamber is the U.S. Lab, a component of the International Space Station. The 32,000-pound scientific research lab, named Destiny, is the first Space Station element to spend seven days in the renovated vacuum chamber for a leak test. Destiny is scheduled to be launched on Shuttle mission STS-98, the 5A assembly mission, targeted for Jan. 18, 2001. During the mission, the crew will install the Lab in the Space Station during a series of three space walks. The STS-98 mission will provide the Station with science research facilities and expand its power, life support and control capabilities. The U.S. Lab module continues a long tradition of microgravity materials research, first conducted by Skylab and later Shuttle and Spacelab missions. Destiny is expected to be a major feature in future research, providing facilities for biotechnology, fluid physics, combustion, and life sciences research.

  17. Modeling, Calibration, and Verification of a Fission Chamber for ACRR Experimentersa

    NASA Astrophysics Data System (ADS)

    Coburn, Jonathan; Luker, S. Michael; Parma, Edward J.; DePriest, K. Russell

    2016-02-01

    When performing research at a reactor facility, experimenters often need to determine the neutron fluence achieved during an operation. Facilities typically provide guidance in the form of neutron fluence per megajoule (MJ) or through passive dosimetry results. After experiment completion, there is sometimes a delay of several days (or weeks) before the passive dosimetry results are available. In the interim, an experimenter does not have confirmation that the desired irradiation levels were reached. Active dosimetry may provide an estimate of neutron fluxes, but few active detectors are available that have been calibrated to measure neutron fluxes obtained inside the Annular Core Research Reactor (ACRR) central cavity environment. For past experiments at the ACRR, the neutron fluence was calculated by integrating the response of a fission chamber rate detection signal and then normalizing this integral to fluence determined from passive dosimetry. An alternative method of directly measuring neutron flux is desired; the new methodology described provides a complete neutron flux profile after a reactor pulse, utilizing fission chamber physics in combination with a compensating ion chamber to extract and convert a current signal to neutron flux as a function of time. Work supported by the United States Department of Energy at Sandia National Laboratories. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  18. A combination drift chamber/pad chamber for very high readout rates

    SciTech Connect

    Spiegel, L.; Cataldi, G.; Elia, V.; Mazur, P.; Murphy, C.T.; Smith, R.P.; Yang, W. ); Alexopoulos, T.; Durandet, C.; Erwin, A.; Jennings, J. ); Antoniazzi, L.; Introzzi, G.; Lanza, A.; Liguori, G.; Torre, P. Istituto Nazionale di Fisica Nucleare, Rome ); Arenton, M.; Conetti, S.

    1991-11-01

    Six medium-sized ({approx}1 {times} 2 m{sup 2}) drift chambers with pad and stripe readout have been constructed for and are presently operating in Fermi National Accelerator Laboratory experiment E-771. Each chamber module actually represents a pair of identical planes: two sets of anode wires, two sets of stripes, and two sets of pads. The wire planes are read out separately and represent X measurements in the coordinate system of the experiment. The twin stripe and pad planes are internally paired within the chamber modules; stripe signals represent Y measurements and pad signals combination X and Y measurements. Signals which develop on the stripes and pads are mirror (but inverted) images of what is seen on the wires. In addition to being used in the off-line pattern recognition, pad signals are also used as inputs to an on-line high transverse momentum (pt) trigger processor. While the techniques involved in the design and construction of the chambers are not novel, they may be of interest to experiments contemplating very large area, high rate chambers for future spectrometers.

  19. ORNL irradiation creep facility

    SciTech Connect

    Reiley, T.C.; Auble, R.L.; Beckers, R.M.; Bloom, E.E.; Duncan, M.G.; Saltmarsh, M.J.; Shannon, R.H.

    1980-09-01

    A machine was developed at ORNL to measure the rates of elongation observed under irradiation in stressed materials. The source of radiation is a beam of 60 MeV alpha particles from the Oak Ridge Isochronous Cyclotron (ORIC). This choice allows experiments to be performed which simulate the effects of fast neutrons. A brief review of irradiation creep and experimental constraints associated with each measurement technique is given. Factors are presented which lead to the experimental choices made for the Irradiation Creep Facility (ICF). The ICF consists of a helium-filled chamber which houses a high-precision mechanical testing device. The specimen to be tested must be thermally stabilized with respect to the temperature fluctuations imposed by the particle beam which passes through the specimen. Electrical resistance of the specimen is the temperature control parameter chosen. Very high precision in length measurement and temperature control are required to detect the small elongation rates relevant to irradiation creep in the test periods available (approx. 1 day). The apparatus components and features required for the above are presented in some detail, along with the experimental procedures. The damage processes associated with light ions are discussed and displacement rates are calculated. Recent irradiation creep results are given, demonstrating the suitability of the apparatus for high resolution experiments. Also discussed is the suitability of the ICF for making high precision thermal creep measurements.

  20. DFL, Canada's Space AIT Facilities - Current and Planned Capabilities

    NASA Astrophysics Data System (ADS)

    Singhal, R.; Mishra, S.; Choueiry, E.; Dumoulin, J.; Ahmed, S.

    2004-08-01

    The David Florida Laboratory (DFL) of the Canadian Space Agency is the Canadian national ISO 9001:2000 registered facility for the assembly, integration, and (environmental) testing of space hardware. This paper briefly describes the three main qualification facilities: Structural Qualification Facilities (SQF); Radio Frequency Qualification Facilities (RFQF); and Thermal Qualification Facilities (TQF). The paper also describes the planned/new upgrades/improvements to the DFL's existing capabilities. These include: cylindrical near-field antenna measurement system, current capabilities in multi-frequency multi-band passive intermodulation (PIM) measurement; combined thermal/vibration test facility, improvement in efficiency and performance of the photogrammetry capability, acquisition of an additional mass properties measurement system for small and micro-satellites; combined control and data acquisition system for all existing thermal vacuum facilities, plus a new automatic thermal control system and hypobaric chamber.