Science.gov

Sample records for katrin jgar jt

  1. JT-60 Control System

    SciTech Connect

    Yonekawa, I.; Kawamata, Y.; Totsuka, T.; Akasaka, H.; Sueoka, M.; Kurihara, K.; Kimura, T.

    2002-09-15

    The present status of the JT-60U control system is reported including its original design concept, the progress of the system, and various modifications since the JT-60 upgrade. This control system has features of a functionally distributed and hierarchical structure, using CAMAC interfaces initially, which have been replaced by versatile module Europe (VME)-bus interfaces, and a protective interlock system composed of both software and hard-wired interlock logics. Plant monitoring and control are performed by efficient data communication through CAMAC highways and Ethernet with TCP/IP protocols. Sequential control of plasma discharges is executed by a combination of a remodeled VME-bus system and a timing system. A real-time plasma control system and a human interface system have been continuously modified corresponding to the progress of JT-60U experiments.

  2. Status of the neutrino mass experiment KATRIN

    SciTech Connect

    Bornschein, L.; Bornschein, B.; Sturm, M.; Roellig, M.; Priester, F.

    2015-03-15

    The most sensitive way to determine the neutrino mass scale without further assumptions is to measure the shape of a tritium beta spectrum near its kinematic end-point. Tritium is the nucleus of choice because of its low endpoint energy, superallowed decay and simple atomic structure. Within an international collaboration the Karlsruhe Tritium Neutrino experiment (KATRIN) is currently being built up at KIT. KATRIN will allow a model-independent measurement of the neutrino mass scale with an expected sensitivity of 0.2 eV/c{sup 2} (90% CL). KATRIN will use a source of ultrapure molecular tritium. This contribution presents the status of the KATRIN experiment, thereby focusing on its Calibration and Monitoring System (CMS), which is the last component being subject to research/development. After a brief overview of the KATRIN experiment in Section II the CMS is introduced in Section III. In Section IV the Beta Induced X-Ray Spectroscopy (BIXS) as method of choice to monitor the tritium activity of the KATRIN source is described and first results are presented.

  3. The closed tritium cycle of KATRIN

    NASA Astrophysics Data System (ADS)

    Bornschein, B.; The Katrin Collaboration

    2006-07-01

    The objective of the KArlsruhe TRItium Neutrino experiment (KATRIN) is a direct measurement of the absolute mass of the electron (anti)neutrino by means of a precise spectroscopy of the tritium β-spectrum near its endpoint. KATRIN combines an ultra-luminous molecular windowless tritium source (WGTS) with a high resolution electrostatic retarding spectrometer. It is planned to inject ultra-cold molecular tritium gas of high isotopic purity (>95%) through a set of capillaries at the middle of the 10 m long WGTS tube. For a gas injection pressure of 3.4×10 -3 mbar and a source temperature of 27 K, the column density of the WGTS is fixed to the reference value of 5×10 17 molecules/cm 2. Since the main systematic uncertainty of the WGTS is associated with the column density, it has to be known to a precision of 0.1%. This stability is the most challenging requirement for the KATRIN WGTS and has essentially influenced its design and the design of the connected tritium cycles. Technical solutions to meet these demands are the proposed WGTS tube cooling system by means of two-phase neon to a stability of ±30 mK and the setup of a so-called Inner Loop to achieve a tritium injection rate of 4.7 Ci/s=1.7×10 11 Bq/s (=40 g tritium throughput per day) with a stability on the level of 0.1%. The Tritium Laboratory Karlsruhe is worldwide the only scientific laboratory which can provide the infrastructure necessary to accomplish such a challenging task.

  4. EM field, tracking and scattering simulations for the KATRIN experiment

    NASA Astrophysics Data System (ADS)

    Glück, Ferenc; KATRIN Collaboration

    2013-02-01

    The aim of the KATRIN experiment is to determine the absolute neutrino mass scale in a model independent way, by measuring the electron energy spectrum shape near the endpoint of tritium beta decay. For this purpose, the KATRIN experiment uses two spectrometers with high voltage, and many superconducting and air coils, to create the necessary electric and magnetic fields. In order to design the spectrometer electrodes and the coils, and to investigate and understand the various background processes and systematic effects, one needs various accurate electric and magnetic field, charged particle tracking and scattering computations, for which we use mainly our self-written C and C++ codes.

  5. Penning Trap Searches in the KATRIN Main Spectrometer

    NASA Astrophysics Data System (ADS)

    Wierman, Kevin; Katrin Collaboration

    2015-10-01

    The Karlsruhe Tritium Neutrino Experiment (KATRIN) aims to make a precision measurement of the tritium beta decay spectrum with a projected sensitivity to neutrino mass of 200 meV. Meeting this goal requires low backgrounds in the beta decay endpoint region. In KATRIN, spatially confined charged particles represent a potential source of backgrounds and systematic errors. Trapping conditions can occur in KATRIN's 10m diameter main spectrometer due to the high magnetic and electrostatic fields required to momentum analyze the electrons. Backgrounds are generated by trapped particles due to scattering off residual gas in the spectrometer causing negative ions to be accelerated towards KATRIN's detector system. Additionally, systematic errors in the neutrino mass measurement can be caused by the electrostatic field generated by trapped electrons. To search for these conditions, the spectrometer was probed by a monoenergetic electron source to determine trapping probabilities as a function of the applied electric and magnetic fields. We acknowledge the support of the German Helmholtz Association, the German Ministry for Education and Research, the Helmholtz Alliance for Astroparticle Physics, the Grant Agency of the Czech Republic, and the US Department of Energy.

  6. First tritium results of the KATRIN test experiment TRAP

    SciTech Connect

    Eichelhardt, F.; Bornschein, B.; Bornschein, L.; Kazachenko, O.; Kernert, N.; Sturm, M.

    2008-07-15

    The TRAP experiment (Tritium Argon frost Pump) has been built at the Tritium Laboratory Karlsruhe (TLK) as a test rig for the Cryogenic Pumping Section (CPS) of the Karlsruhe Tritium Neutrino Experiment (KATRIN). TRAP employs a heterogeneous layer of pre-condensed argon to adsorb hydrogen isotopes at {approx} 4.2 K This paper presents results obtained in the first three tritium experiments with TRAP. (authors)

  7. Wall conditioning in JT-60

    NASA Astrophysics Data System (ADS)

    Arai, T.; Yamamoto, M.; Akino, N.; Kodama, K.; Nakamura, H.; Niikura, S.; Takatsu, H.; Shimizu, M.; Ohkubo, M.; Ohta, M.; JT-60 Team

    1987-02-01

    The vacuum vessel of JT-60 has a volume of 160 m 3 and a vacuum side surface of 2750 m 2 containing the surfaces of the first wall and many types of ports. The first wall is made of 20 μm TiC coated molybdenum and Inconel 625, bolted to the inner surface of the vacuum vessel. The vacuum vessel is evacuated with four identical pumping systems with a total pumping speed of 29 m 3/s for hydrogen. The wall conditioning procedure consisted of two wipes with special cloths wetted by freon after hot water and freon jet cleaning, and three bakeouts were carried out before the first plasma production. An ultimate pressure of 7.4 × 10 -7 Pa and an outgassing rate of 6.8 × 10 -10 Pa m 3/s m 2 were obtained. Low current pulse discharge cleaning (TDC) was carried out for two weeks at a vacuum vessel temperature of 200°C. The TDC is performed typically with a plasma current of 30 kA, a pulse duration of 40 ms, a repetition period in the range from 0.3 s to 1.2 s, a hydrogen pressure of 5.0 × 10 -3 Pa, and a toroidal field of 0.45 T. The TDC conditioning for 50 h removed a quantity of water vapor corresponding to approximately 0.3 g. The main residual gases consisting of hydrocarbons, were monitored in addition to hydrogen and carbon monoxide.

  8. JT8D and JT9D jet engine performance improvement program. Task 1: Feasibility analysis

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.; Webb, D. E.

    1979-01-01

    JT8D and JT9D component performance improvement concepts which have a high probability of incorporation into production engines were identified and ranked. An evaluation method based on airline payback period was developed for the purpose of identifying the most promising concepts. The method used available test data and analytical models along with conceptual/preliminary designs to predict the performance improvements, weight, installation characteristics, cost for new production and retrofit, maintenance cost, and qualitative characteristics of candidate concepts. These results were used to arrive at the concept payback period, which is the time required for an airline to recover the investment cost of concept implementation.

  9. Commissioning of the vacuum system of the KATRIN Main Spectrometer

    NASA Astrophysics Data System (ADS)

    Arenz, M.; Babutzka, M.; Bahr, M.; Barrett, J. P.; Bauer, S.; Beck, M.; Beglarian, A.; Behrens, J.; Bergmann, T.; Besserer, U.; Blümer, J.; Bodine, L. I.; Bokeloh, K.; Bonn, J.; Bornschein, B.; Bornschein, L.; Büsch, S.; Burritt, T. H.; Chilingaryan, S.; Corona, T. J.; De Viveiros, L.; Doe, P. J.; Dragoun, O.; Drexlin, G.; Dyba, S.; Ebenhöch, S.; Eitel, K.; Ellinger, E.; Enomoto, S.; Erhard, M.; Eversheim, D.; Fedkevych, M.; Felden, A.; Fischer, S.; Formaggio, J. A.; Fränkle, F.; Furse, D.; Ghilea, M.; Gil, W.; Glück, F.; Gonzalez Ureña, A.; Görhardt, S.; Groh, S.; Grohmann, S.; Grössle, R.; Gumbsheimer, R.; Hackenjos, M.; Hannen, V.; Harms, F.; Haußmann, N.; Heizmann, F.; Helbing, K.; Herz, W.; Hickford, S.; Hilk, D.; Hillen, B.; Höhn, T.; Holzapfel, B.; Hötzel, M.; Howe, M. A.; Huber, A.; Jansen, A.; Kernert, N.; Kippenbrock, L.; Kleesiek, M.; Klein, M.; Kopmann, A.; Kosmider, A.; Kovalík, A.; Krasch, B.; Kraus, M.; Krause, H.; Krause, M.; Kuckert, L.; Kuffner, B.; La Cascio, L.; Lebeda, O.; Leiber, B.; Letnev, J.; Lobashev, V. M.; Lokhov, A.; Malcherek, E.; Mark, M.; Martin, E. L.; Mertens, S.; Mirz, S.; Monreal, B.; Müller, K.; Neuberger, M.; Neumann, H.; Niemes, S.; Noe, M.; Oblath, N. S.; Off, A.; Ortjohann, H.-W.; Osipowicz, A.; Otten, E.; Parno, D. S.; Plischke, P.; Poon, A. W. P.; Prall, M.; Priester, F.; Ranitzsch, P. C.-O.; Reich, J.; Rest, O.; Robertson, R. G. H.; Röllig, M.; Rosendahl, S.; Rupp, S.; Ryšavý, M.; Schlösser, K.; Schlösser, M.; Schönung, K.; Schrank, M.; Schwarz, J.; Seiler, W.; Seitz-Moskaliuk, H.; Sentkerestiová, J.; Skasyrskaya, A.; Slezák, M.; Špalek, A.; Steidl, M.; Steinbrink, N.; Sturm, M.; Suesser, M.; Telle, H. H.; Thümmler, T.; Titov, N.; Tkachev, I.; Trost, N.; Unru, A.; Valerius, K.; Vénos, D.; Vianden, R.; Vöcking, S.; Wall, B. L.; Wandkowsky, N.; Weber, M.; Weinheimer, C.; Weiss, C.; Welte, S.; Wendel, J.; Wierman, K. L.; Wilkerson, J. F.; Winzen, D.; Wolf, J.; Wüstling, S.; Zacher, M.; Zadoroghny, S.; Zbořil, M.

    2016-04-01

    The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. An integral energy analysis will be performed by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. A system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10‑11 mbar range. It is demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.

  10. Data Processing and Analysis Systems for JT-60U

    SciTech Connect

    Matsuda, T.; Totsuka, T.; Tsugita, T.; Oshima, T.; Sakata, S.; Sato, M.; Iwasaki, K.

    2002-09-15

    The JT-60U data processing system is a large computer complex gradually modernized by utilizing progressive computer and network technology. A main computer using state-of-the-art CMOS technology can handle {approx}550 MB of data per discharge. A gigabit ethernet switch with FDDI ports has been introduced to cope with the increase of handling data. Workstation systems with VMEbus serial highway drivers for CAMAC have been developed and used to replace many minicomputer systems. VMEbus-based fast data acquisition systems have also been developed to enlarge and replace a minicomputer system for mass data.The JT-60U data analysis system is composed of a JT-60U database server and a JT-60U analysis server, which are distributed UNIX servers. The experimental database is stored in the 1TB RAID disk of the JT-60U database server and is composed of ZENKEI and diagnostic databases. Various data analysis tools are available on the JT-60U analysis server. For the remote collaboration, technical features of the data analysis system have been applied to the computer system to access JT-60U data via the Internet. Remote participation in JT-60U experiments has been successfully conducted since 1996.

  11. Gas and Pellet Injection Systems for JT-60 and JT-60U

    SciTech Connect

    Kizu, K.; Hiratsuka, H.; Miyo, Y.; Ichige, H.; Sasajima, T.; Nishiyama, T.; Masaki, K.; Honda, M.; Miya, N.; Hosogane, N.

    2002-09-15

    Designs and operations of the gas system and pellet injection systems for JT-60 and JT-60U are described. A gas injection valve that is a key component of the gas injection system was developed using a multilayer piezoelectric element. The maximum flow rate of this system is 43.3 Pa.m{sup 3}/s. The valve has mechanism for adjustment at atmospheric side meaning that a repair and an adjustment can be conducted without ventilation inside a vacuum vessel. It was confirmed that the effect of magnetic field and temperature change on the valves in the JT-60U environment was negligible.In JT-60U, two systems of pellet injector - a pneumatic drive and a centrifugal one - were developed. The pneumatic type attained a pellet velocity of 2.3 km/s, which was the world record at the time in 1988. On the other hand, the centrifugal one was developed in 1998. This injector can eject trains of up to 40 cubic (2.1 mm{sup 3}) pellets at frequencies of 1 to 10 Hz and speed of 0.1 to 1.0 km/s. A guide tube for a magnetic high field side injection (HFS) (top) was also developed in 1999. The pellet injection experiment with the HFS system started in 2000. In addition, another guide tube for HFS(mid) injection was newly developed and installed in March 2001. These systems are working well.

  12. An angular-selective electron source for the KATRIN experiment

    NASA Astrophysics Data System (ADS)

    Beck, M.; Bokeloh, K.; Hein, H.; Bauer, S.; Baumeister, H.; Bonn, J.; Ortjohann, H.-W.; Ostrick, B.; Rosendahl, S.; Streubel, S.; Valerius, K.; Zbořil, M.; Weinheimer, C.

    2014-11-01

    The KATRIN experiment is going to search for the average mass of the electron antineutrino with a sensitivity of 0.2 eV/c2. It uses a retardation spectrometer of MAC-E filter type to accurately measure the shape of the electron spectrum at the endpoint of tritium beta decay. In order to achieve the planned sensitivity the transmission properties of the spectrometer have to be understood with high precision for all initial conditions. For this purpose an electron source has been developed that emits single electrons at adjustable total energy and adjustable emission angle. The emission is pointlike and can be moved across the full flux tube that is imaged onto the detector. Here, we demonstrate that this novel type of electron source can be used to investigate the transmission properties of a MAC-E filter in detail.

  13. Engine component improvement: JT8D and JT9D performance improvements

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1978-01-01

    A feasibility analysis screening method for predicting the airline acceptance of a proposed engine performance improvement modification was developed. Technical information derived from available test data and analytical models is used along with conceptual/preliminary designs to establish the predicted performance improvement, weight and installation characteristics, the cost for new production and retrofit, maintenance cost and qualitative characteristics of the performance improvement concepts being evaluated. These results are used to arrive at the payback period, which is the time required for an airline to recover the investment cost of concept implementation, and to predict the amount of fuel saved by a performance improvement concept. The assumptions used to calculate the payback period and fuel saved are discussed. A summary of the results when the screening method is applied is presented for several representative JT8D and JT9D performance improvement concepts. An example of the input information used to develop the summary results is shown.

  14. JT-60SA superconducting magnet system

    NASA Astrophysics Data System (ADS)

    Koide, Y.; Yoshida, K.; Wanner, M.; Barabaschi, P.; Cucchiaro, A.; Davis, S.; Decool, P.; Di Pietro, E.; Disset, G.; Genini, L.; Hajnal, N.; Heller, R.; Honda, A.; Ikeda, Y.; Kamada, Y.; Kashiwa, Y.; Kizu, K.; Kamiya, K.; Murakami, H.; Michel, F.; Marechal, J. L.; Phillips, G.; Polli, G. M.; Rossi, P.; Shibanuma, K.; Takahata, K.; Tomarchio, V.; Tsuchiya, K.; Usui, K.; Verrecchia, M.; Zani, L.

    2015-08-01

    The most distinctive feature of the superconducting magnet system for JT-60SA is the optimized coil structure in terms of the space utilization as well as the highly accurate coil manufacturing, thus meeting the requirements for the steady-state tokamak research: a conceptually new outer inter-coil structure separated from the casing is introduced to the toroidal field coils to realize their slender shape, allowing large-bore diagnostic ports for detailed plasma measurements. A method to minimize the manufacturing error of the equilibrium-field coils has been established, aiming at the precise plasma shape/position control. A compact butt-joint has been successfully developed for the Central Solenoid, which allows an optimized utilization of the limited space for the Central Solenoid to extend the duration of the plasma pulse.

  15. JT8D-100 turbofan engine, phase 1. [noise reduction

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The JT8D turbofan engine, widely used in short and medium range transport aircraft, contributes substantially to airport community noise. The jet noise is predominant in the JT8D engine and may be reduced in a modified engine, without loss of thrust, by increasing the airflow to reduce jet velocity. A configuration study evaluated the effects of fan airflow, fan pressure ratio, and bypass ratio on noise, thrust, and fuel comsumption. The cycle selected for the modified engine was based upon an increased diameter, single-stage fan and two additional core engine compressor stages, which replace the existing two-stage fan. Modifications were also made to the low pressure turbine to provide the increased torque required by the larger diameter fan. The resultant JT8D-100 engine models have the following characteristics at take-off thrust, compared to the current JT8D engine: Airflow and bypass ratio are increased, and fan pressure ratio and engine speed are reduced. The resultant engine is also longer, larger in diameter, and heavier than the JT8D base model, but these latter changes are compensated by the increased thrust and decreased fuel comsumption of the modified engine, thus providing the capability for maintaining the performance of the current JT8D-powered aircraft.

  16. JT15D simulated flight data evaluation

    NASA Technical Reports Server (NTRS)

    Holm, R. G.

    1984-01-01

    The noise characteristics of the JT15D turbofan engine was analyzed with the objectives of: (1) assessing the state-of-art ability to simulate flight acoustic data using test results acquired in wind tunnel and outdoor (turbulence controlled) environments; and (2) predicting the farfield noise directivity of the blade passage frequency (BPF) tonal components using results from rotor blade mounted dynamic pressure instrumentation. Engine rotor tip speeds at subsonic, transonic, and supersonic conditions were evaluated. The ability to simulate flight results was generally within 2-3 dB for both outdoor and wind tunnel acoustic results. Some differences did occur in the broadband noise level and in the multiple-pure-tone harmonics at supersonic tip speeds. The prediction of blade passage frequency tone directivity from dynamic pressure measurements was accomplished for the three tip speed conditions. Predictions were made of the random and periodic components of the tone directivity. The technique for estimating the random tone component used hot wire data to establish a correlation between dynamic pressure and turbulence intensity. This prediction overestimated the tone level by typically 10 dB with the greatest overestimates occurring at supersonic conditions.

  17. Measurement and reduction of low-level radon background in the KATRIN experiment

    SciTech Connect

    Fränkle, F. M.

    2013-08-08

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a next generation, model independent, large scale experiment to determine the mass of the electron anti-neutrino by investigating the kinematics of tritium beta decay with a sensitivity of 200 meV/c{sup 2}. The measurement setup consists of a high luminosity windowless gaseous molecular tritium source (WGTS), a differential and cryogenic pumped electron transport and tritium retention section, a tandem spectrometer section (pre-spectrometer and main spectrometer) for energy analysis, followed by a detector system for counting transmitted beta decay electrons. Measurements performed at the KATRIN pre-spectrometer test setup showed that the decay of radon (Rn) atoms in the volume of the KATRIN spectrometers is a major background source. Rn atoms from low-level radon emanation of materials inside the vacuum region of the KATRIN spectrometers are able to penetrate deep into the magnetic flux tube so that the alpha decay of Rn contributes to the background. Of particular importance are electrons emitted in processes accompanying the Rn alpha decay, such as shake-off, internal conversion of excited levels in the Rn daughter atoms and Auger electrons. Lowenergy electrons (< 100 eV) directly contribute to the background in the signal region. High-energy electrons can be stored magnetically inside the volume of the spectrometer and are able to create thousands of secondary electrons via subsequent ionization processes with residual gas molecules. In order to reduce the Rn induced background different active and passive counter measures were developed and tested. This proceeding will give an overview on Rn sources within the KATRIN spectrometer, describes how Rn decays inside the spectrometer produce background events at the detector and presents different counter measures to reduce the Rn induced background.

  18. Performance of JT-60SA divertor Thomson scattering diagnostics.

    PubMed

    Kajita, Shin; Hatae, Takaki; Tojo, Hiroshi; Enokuchi, Akito; Hamano, Takashi; Shimizu, Katsuhiro; Kawashima, Hisato

    2015-08-01

    For the satellite tokamak JT-60 Super Advanced (JT-60SA), a divertor Thomson scattering measurement system is planning to be installed. In this study, we improved the design of the collection optics based on the previous one, in which it was found that the solid angle of the collection optics became very small, mainly because of poor accessibility to the measurement region. By improvement, the solid angle was increased by up to approximately five times. To accurately assess the measurement performance, background noise was assessed using the plasma parameters in two typical discharges in JT-60SA calculated from the SONIC code. Moreover, the influence of the reflection of bremsstrahlung radiation by the wall is simulated by using a ray tracing simulation. The errors in the temperature and the density are assessed based on the simulation results for three typical field of views. PMID:26329196

  19. Performance verification tests of JT-60SA CS model coil

    NASA Astrophysics Data System (ADS)

    Obana, Tetsuhiro; Murakami, Haruyuki; Takahata, Kazuya; Hamaguchi, Shinji; Chikaraishi, Hirotaka; Mito, Toshiyuki; Imagawa, Shinsaku; Kizu, Kaname; Natsume, Kyohei; Yoshida, Kiyoshi

    2015-11-01

    As a final check of the coil manufacturing method of the JT-60 Super Advanced (JT-60SA) central solenoid (CS), we verified the performance of a CS model coil. The model coil comprised a quad-pancake wound with a Nb3Sn cable-in-conduit conductor. Measurements of the critical current, joint resistance, pressure drop, and magnetic field were conducted in the verification tests. In the critical-current measurement, the critical current of the model coil coincided with the estimation derived from a strain of -0.62% for the Nb3Sn strands. As a result, critical-current degradation caused by the coil manufacturing process was not observed. The results of the performance verification tests indicate that the model coil met the design requirements. Consequently, the manufacturing process of the JT-60SA CS was established.

  20. Dynamic design of gas sorption J-T refrigerator

    NASA Technical Reports Server (NTRS)

    Chan, C. K.

    1986-01-01

    A long-life Joule-Thomson refrigerator which is heat powered, involves no sealing, and has few mechanical parts is desirable for long-term sensor cooling in space. In the gas-sorption J-T refrigerator, cooling is achieved by gas sorption (either adsorption or absorption) processes. Currently, a modular, single-stage refrigerator is being designed and built to be operated at 20 K. The design was analyzed using a dynamic model, which is described here. The model includes the kinetics of the compressors and the heat switches, the heat transfer of the pre-coolers and the heat exchangers, the on/off ratio of the check valves, and the impedance of the J-T valve. The cooling power, the cycle time, and the operating conditions were obtained in terms of the power input, the heat sink temperature, and the J-T impedance.

  1. Development of JT-60SA superconducting magnet system

    NASA Astrophysics Data System (ADS)

    Yoshida, K.; Tsuchiya, K.; Kizu, K.; Murakami, H.; Kamiya, K.; Obana, T.; Takahata, K.; Peyrot, M.; Barabaschi, P.

    2010-11-01

    The upgrade of JT-60U magnet system to superconducting coils (JT-60SA) is progressing by both parties of Japanese government and European commission in the framework of the Broader Approach agreement. The magnet system for JT-60SA consists of 18 Toroidal Field (TF) coils, a Central Solenoid (CS) with four modules, six Equilibrium Field (EF) coils. The TF coil case encloses the winding pack and is the main structural component of the magnet system. The CS consists of four independent winding pack modules, which is support from the bottom of the TF coils. The six EF coils are attached to the TF coil cases through supports with flexible plates allowing radial displacements. The construction of CS and EF coils was started in 2008 by Japan Atomic Energy Agency (JAEA). The construction of TF coils will be started in 2009 by Fusion for Energy and European voluntary contributors. This paper introduces the design of the JT-60SA superconducting magnet system and activities for development of magnet components in Japan.

  2. JT-60U high performance regimes

    NASA Astrophysics Data System (ADS)

    Ishida, S.; JT-60 Team

    1999-09-01

    High performance regimes of JT-60U plasmas are presented with an emphasis upon the results from the use of a semiclosed pumped divertor with a W shaped geometry. Plasma performance in transient and quasi-steady states has been significantly improved in reversed shear and high ?p regimes. The reversed shear regime elevated an equivalent QeqDT transiently up to 1.25 (nD(0) ?ETi(0) = 8.6 1020m-3skeV) in a reactor relevant thermonuclear dominant regime. Long sustainment of enhanced confinement with internal transport barriers (ITBs) with fully non-inductive current drive in a reversed shear discharge was successfully demonstrated with LH wave injection. Performance sustainment has been extended in the high ?p regime with high triangularity, achieving a long sustainment of plasma conditions equivalent to QeqDT approx 0.16 (nD(0) ?ETi(0) approx 1.4 1020 m-3skeV) for ~4.5 s with a large non-inductive current drive fraction of 60-70% of the plasma current. Thermal and particle transport analyses show significant reduction of thermal and particle diffusivities around the ITB, resulting in a strong Er shear in the ITB region. The W shaped divertor is effective for helium ash exhaust, demonstrating a steady exhaust capability of ?*He/?E approx 3-10, which is favourable for ITER. Suppression of neutral backflow and chemical sputtering effects has been observed, while MARFE onset density is rather decreased. Negative ion based neutral beam injection (N-NBI) experiments have created a clear H mode transition. An enhanced ionization cross-section due to multistep ionization processes was confirmed as theoretically predicted. A current density profile driven by N-NBI is measured in good agreement with the theoretical prediction. N-NBI induced TAEs characterized as persistent and bursting oscillations have been observed from a low hot ? of langle?hrangle approx 0.1-0.2% without a significant loss of fast ions.

  3. Tests of by-pass diodes at cryogenic temperatures for the KATRIN magnets

    SciTech Connect

    Gil, W.; Bolz, H.; Jansen, A.; Müller, K.; Steidl, M.; Hagedorn, D.

    2014-01-27

    The Karlsruhe Tritium Neutrino experiment (KATRIN) requires a series of superconducting solenoid magnets for guiding beta-electrons from the source to the detector. By-pass diodes will operate at liquid helium temperatures to protect the superconducting magnets and bus bars in case of quenches. The operation conditions of the by-pass diodes depend on the different magnet systems of KATRIN. Therefore, different diode stacks are designed with adequate copper heat sinks assuming adiabatic conditions. The by-pass diode stacks have been submitted to cold tests both at liquid nitrogen and liquid helium temperatures for checking operation conditions. This report presents the test set up and first results of the diode characteristics at 300 K and 77 K, as well as of endurance tests of the diode stacks at constant current load at 77 K and 4.2 K.

  4. Electron line shape and transmission function of the KATRIN monitor spectrometer

    SciTech Connect

    Slezák, M.

    2013-12-30

    Knowledge of the neutrino mass is of particular interest in modern neutrino physics. Besides the neutrinoless double beta decay and cosmological observation information about the neutrino mass is obtained from single beta decay by observing the shape of the electron spectrum near the endpoint. The KATRIN β decay experiment aims to push the limit on the effective electron antineutrino mass down to 0.2 eV/c{sup 2}. To reach this sensitivity several systematic effects have to be under control. One of them is the fluctuations of the absolute energy scale, which therefore has to be continuously monitored at very high precision. This paper shortly describes KATRIN, the technique for continuous monitoring of the absolute energy scale and recent improvements in analysis of the monitoring data.

  5. Neutrinos secretly converting to lighter particles to please both KATRIN and the cosmos

    NASA Astrophysics Data System (ADS)

    Farzan, Yasaman; Hannestad, Steen

    2016-02-01

    Within the framework of the Standard Model of particle physics and standard cosmology, observations of the Cosmic Microwave Background (CMB) and Baryon Acoustic Oscillations (BAO) set stringent bounds on the sum of the masses of neutrinos. If these bounds are satisfied, the upcoming KATRIN experiment which is designed to probe neutrino mass down to ~ 0.2 eV will observe only a null signal. We show that the bounds can be relaxed by introducing new interactions for the massive active neutrinos, making neutrino masses in the range observable by KATRIN compatible with cosmological bounds. Within this scenario, neutrinos convert to new stable light particles by resonant production of intermediate states around a temperature of T~ keV in the early Universe, leading to a much less pronounced suppression of density fluctuations compared to the standard model.

  6. 1450 m^3 at 10^-9 Pa: One of the KATRIN Challenges

    SciTech Connect

    Christian Day; R. Gumbsheimer; W. Herz; J. Wolf; J. Bonn; R. Reid; G.R. Myneni

    2006-11-12

    The KATRIN project is a challenging experiment to measure the mass of the electron neutrino directly with a sensitivity of 0.2 eV. It is a next generation tritium beta-decay experiment scaling up the size and precision of previous experiments by an order of magnitude as well as the intensity of the tritium beta source. Ultrafine spectrometric analysis of the energy distribution of the decay electrons at their very endpoint of 18.57 keV is the key to derive the neutrino mass. This is provided by a high-resolution spectrometer of unique size (10 m in diameter, 22 m in length). To avoid any negative influence from residual gas, the spectrometer vessel is designed to UHV/XHV conditions (an ultimate total pressure of below 10{sup -9} Pa and a wall outgassing rate below 10{sup -13} Pam{sup 3}/scm{sup 2}). The paper shortly describes the experimental idea behind KATRIN. The emphasis will then be given to the pumping concept for how to achieve the target parameters and to the manufacturing of the spectrometer tank. Critical issues will also be discussed (surface treatment, welding, transportation). Finally, a description of the current status and an outlook on the overall KATRIN schedule completes the paper.

  7. Results of acoustic testing of the JT8D-109 refan engines

    NASA Technical Reports Server (NTRS)

    Burdsall, E. A.; Brochu, F. P.; Scaramella, V. M.

    1975-01-01

    A JT8D engine was modified to reduce jet noise levels by 6-8 PNdB at takeoff power without increasing fan generated noise levels. Designated the JT8D-109, the modified engines featured a larger single stage fan, and acoustic treatment in the fan discharge ducts. Noise levels were measured on an outdoor test facility for eight engine/acoustic treatment configurations. Compared to the baseline JT8D, the fully treated JT8D-109 showed reductions of 6 PNdB at takeoff, and 11 PNdB at a typical approach power setting.

  8. MIXING STUDY FOR JT-71/72 TANKS

    SciTech Connect

    Lee, S.

    2013-11-26

    All modeling calculations for the mixing operations of miscible fluids contained in HBLine tanks, JT-71/72, were performed by taking a three-dimensional Computational Fluid Dynamics (CFD) approach. The CFD modeling results were benchmarked against the literature results and the previous SRNL test results to validate the model. Final performance calculations were performed by using the validated model to quantify the mixing time for the HB-Line tanks. The mixing study results for the JT-71/72 tanks show that, for the cases modeled, the mixing time required for blending of the tank contents is no more than 35 minutes, which is well below 2.5 hours of recirculation pump operation. Therefore, the results demonstrate the adequacy of 2.5 hours’ mixing time of the tank contents by one recirculation pump to get well mixed.

  9. Cryogenic requirements for the JT-60SA Tokamak

    NASA Astrophysics Data System (ADS)

    Michel, Frederic; Hitz, D.; Hoa, Christine; Lamaison, Valerie; Kamiya, Koji; Roussel, Pascal; Wanner, Manfred; Yoshida, Kiyoshi

    2012-06-01

    The superconducting tokamak JT-60SA is part of the Broader Approach Programmeagreed between Japan and Europe. CEA is in charge of the cryogenic system procurementincluding the Warm Compression Station, the gas storages, the Refrigerator Cold Box andthe Auxiliary Cold Box (ACB) which has to be installed on the JAEA Naka site in 2016.This paper summarizes the updated cryogenic requirements for the tokamak JT-60SAcryogenic system. The cryogenic system has a refrigeration capacity of about 9 kW equivalent at 4.5K, to supply cryopump panels at 3.7 K, superconducting magnets and cold structures at 4.4 K, HTS current leads at 50 K, and thermal shields at 80 K. This paper presents the static and variable heat loads of the different cooling loops and the results of the rmohydraulic calculations to derive the transient heat loads at the interface between the magnet system cooling loops and the Auxiliary Cold Box.

  10. JT9D ceramic outer air seal system refinement program

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1982-01-01

    The abradability and durability characteristics of the plasma sprayed system were improved by refinement and optimization of the plasma spray process and the metal substrate design. The acceptability of the final seal system for engine testing was demonstrated by an extensive rig test program which included thermal shock tolerance, thermal gradient, thermal cycle, erosion, and abradability tests. An interim seal system design was also subjected to 2500 endurance test cycles in a JT9D-7 engine.

  11. The 727/JT8D refan side nacelle airloads

    NASA Technical Reports Server (NTRS)

    Bailey, R. W.; Vadset, H. J.

    1974-01-01

    Airloads on the 727/JT8D refan side engine nacelle are presented. These consist of surface static pressure distributions from two low speed wind tunnel tests. External nacelle surface pressures are from testing of a flow-through, body mounted nacelle model, and internal inlet surface pressures are from performance testing of a forced air inlet model. The method for obtaining critical airloads on nacelle components and a representative example are discussed.

  12. Conceptual design of the JT-60SA cryogenic system

    NASA Astrophysics Data System (ADS)

    Lamaison, V.; Beauvisage, J.; Fejoz, P.; Girard, S.; Gonvalves, R.; Gond, R.; Heloin, V.; Michel, F.; Hoa, C.; Kamiya, K.; Roussel, P.; Vallet, J.-C.; Wanner, M.; Yoshida, K.

    2014-01-01

    The superconducting tokamak JT-60 Super Advanced (JT-60SA) is part of the Broader Approach Programme agreed between Europe and Japan. Among other in kind contributions, CEA is in charge of supplying the Cryogenic System which includes a Warm Compression Station, the Refrigerator Cold Box, the Auxiliary Cold Box, a compressed air station and the vacuum systems. The cryogenic system requires a refrigeration capacity of about 8 kW equivalent at 4.5 K. It will supply cryopump panels at 3.7 K, superconducting magnets and cold structures at 4.4 K, HTS current leads at 50 K, and thermal shields between 80 K and 100 K. The contract for design, manufacture, installation and commissioning was signed between CEA and Air Liquide Advanced Technologies (AL-AT) in November 2012. The Cryogenic System shall be operational in 2016. The paper presents the main technical requirements and the limit of supply, the description of the process proposed by AL-AT, the main components, the preliminary layout and the interfaces at the JT-60SA Naka site.

  13. Production of a novel monoclonal antibody, JT-95, which can detect antigen of thyroid carcinoma.

    PubMed

    Takeyama, H; Hosoya, T; Sakurai, K; Mori, Y; Watanabe, M; Kisaki, H; Ohno, T

    1996-04-15

    Monoclonal antibody (MAb) JT-95 was produced by immunization of mice with membrane fractions of a human thyroid carcinoma. Immuno-histochemical staining has demonstrated that the antigen recognized by JT-95 is strongly expressed in 95 (95%) of 100 cases of papillary carcinomas and in 3 (75%) of 4 cases of follicular carcinomas. In benign diseases of the thyroid gland, MAb JT-95 reacted with 0 (0%) of 39 adenomas, 1 (4%) of 21 adenomatous goiters, 0 (0%) of 8 hyperthyroidism specimens, and 3 (38%) of 8 chronic thyroiditis specimens. The antigen detected by MAb JT-95 has an apparent Mr 250,000 in thyroid carcinomas. Moreover, circulating antigen in thyroid carcinoma patients was detected by MAb JT-95 in an ELISA and in Western blotting. The circulating antigen has a Mr 105,000. MAb JT-95 conjugated with (131) I was administrated to nude mice bearing a human thyroid carcinoma. JT-95 131I accumulation at the transplanted tumor was visualized by autoradiography with 2.68-14.75-fold higher levels detected at the xenograft compared to that for normal organs. Based on these data, MAb JT-95 may be useful in the diagnosis detection and therapy of thyroid carcinoma. PMID:8620498

  14. Present status and future prospects of the JT-60SA project

    NASA Astrophysics Data System (ADS)

    Ishida, S.; Barabaschi, P.; Kamada, Y.

    2014-10-01

    The JT-60SA project has been implemented jointly by Europe and Japan since June 2007. After the disassembly of JT-60 from the torus hall had been completed in October 2012, the project achieved the major milestone of starting the tokamak's assembly at the JAEA Naka site in January 2013 following the completion of the cryostat base in Europe and its transport to Japan. Procurement and assembly activities for components such as the superconducting magnet, cryogenic system, power supply, vacuum vessel, divertor and cryostat are progressing on track towards the start of operation in March 2019. In preparation for exploitation, the JT-60SA Research Plan was issued in December 2011, and the research integration activities are addressing JT-60SA data management, validation and analysis tools. This paper overviews the latest evolution of the project in terms of construction and exploitation for JT-60SA.

  15. Development of a J-T Micro Compressor

    NASA Astrophysics Data System (ADS)

    Champagne, P.; Olson, J. R.; Nast, T.; Roth, E.; Collaco, A.; Kaldas, G.; Saito, E.; Loung, V.

    2015-12-01

    Lockheed Martin has developed and tested a space-quality compressor capable of delivering closed-loop gas flow with a high pressure ratio, suitable for driving a Joule- Thomson cold head. The compressor is based on a traditional “Oxford style” dual-opposed piston compressor with linear drive motors and flexure-bearing clearance-seal technology for high reliability and long life. This J-T compressor retains the approximate size, weight, and cost of the ultra-compact, 200 gram Lockheed Martin Pulse Tube Micro Compressor, despite the addition of a flow-rectifying system to convert the AC pressure wave into a steady flow.

  16. Monitoring of the operating parameters of the KATRIN Windowless Gaseous Tritium Source

    NASA Astrophysics Data System (ADS)

    Babutzka, M.; Bahr, M.; Bonn, J.; Bornschein, B.; Dieter, A.; Drexlin, G.; Eitel, K.; Fischer, S.; Glück, F.; Grohmann, S.; Hötzel, M.; James, T. M.; Käfer, W.; Leber, M.; Monreal, B.; Priester, F.; Röllig, M.; Schlösser, M.; Schmitt, U.; Sharipov, F.; Steidl, M.; Sturm, M.; Telle, H. H.; Titov, N.

    2012-10-01

    The KArlsruhe TRItium Neutrino (KATRIN) experiment will measure the absolute mass scale of neutrinos with a sensitivity of mν = 200 meV/c2 by high-precision spectroscopy close to the tritium β-decay endpoint at 18.6 keV. Its Windowless Gaseous Tritium Source (WGTS) is a β-decay source of high intensity (1011 s-1) and stability, where high-purity molecular tritium at 30 K is circulated in a closed loop with a yearly throughput of 10 kg. To limit systematic effects the column density of the source has to be stabilized at the 10-3 level. This requires extensive sensor instrumentation and dedicated control and monitoring systems for parameters such as the beam tube temperature, injection pressure, gas composition and so on. In this paper, we give an overview of these systems including a dedicated laser-Raman system as well as several β-decay activity monitors. We also report on the results of the WGTS demonstrator and other large-scale test experiments giving proof-of-principle that all parameters relevant to the systematics can be controlled and monitored on the 10-3 level or better. As a result of these works, the WGTS systematics can be controlled within stringent margins, enabling the KATRIN experiment to explore the neutrino mass scale with the design sensitivity.

  17. Electromagnetic design of the large-volume air coil system of the KATRIN experiment

    NASA Astrophysics Data System (ADS)

    Glück, Ferenc; Drexlin, Guido; Leiber, Benjamin; Mertens, Susanne; Osipowicz, Alexander; Reich, Jan; Wandkowsky, Nancy

    2013-08-01

    The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to determine the absolute neutrino mass scale with a sensitivity of 200 meV (90% confidence level) by measuring the electron energy spectrum close to the endpoint of molecular tritium β decay. Electrons from a high-intensity gaseous tritium source are guided by a strong magnetic field of a few T to the analyzing plane of the main spectrometer where an integral energy analysis takes place in a low field region (B < 0.5 mT). An essential design feature to obtain adiabatic electron transport through this spectrometer is a large volume air coil system surrounding the vessel. The system has two key tasks: to adjust and fine-tune the magnetic guiding field (low field correction system), as well as to compensate the distorting effects of the earth magnetic field (earth field compensation system). In this paper we outline the key electromagnetic design issues for this very large air coil system, which allows for well-defined electron transmission and optimized background reduction in the KATRIN main spectrometer.

  18. Scale model testing of the jet noise characteristics of the JT8D refan engine nozzle system

    NASA Technical Reports Server (NTRS)

    Reed, D. H.

    1974-01-01

    The results are presented of static scale model acoustic tests of the nozzle system for the JT8D-9 baseline engine and candidate nozzle systems for JT8D-109, JT8D-115, and JT8D-117 refan engines. The objective of these tests was to determine the jet noise benefit of the three refan engine cycles relative to the baseline JT8D-9, and to provide acoustic information toward selection of the optimum primary-secondary area match and centerbody contour for the refan engine cycles. One of the nozzle configurations was tested with and without simulated turbine exit swirl to determine what effect, if any, swirl has no jet noise. The JT8D-109 cycle was found to afford approximately 9 db (0ASPL) jet noise reduction relative to the JT8D-9 when compared on an equal static thrust basis. The JT8D-115 and JT8D-117 afford an 8 db and 6 db reduction, respectively, relative to the JT8D-9, at equal static thrust. Turbine exit swirl was found to have no significant effect on the jet noise of the JT8D-109 nozzle system.

  19. Performance Study on ST/JT Hybrid Cryocoolers Working at Liquid Helium Temperature

    NASA Astrophysics Data System (ADS)

    Dongli, Liu; Xuan, Tao; Xiao, Sun; Zhihua, Gan

    The ST/JT hybridcryocooler consists of a Stirling-typecryocooler and a J-T loop. The common process of steady-state operation is given. Pressure-Enthalpy map analysis and thermodynamic calculation showhow the precooling temperature, high pressure and recuperator effectiveness affect thecooling powerat liquid helium temperature. Applying the current performance level of the Stirling cooler,the overall COP of the hybrid cryocooleris roughly optimized. This performance study shows that the hybrid cryocooler can develop its performance potential with improved J-T compressors with larger pressure ratio and aprecooler working at lower temperature.

  20. Simulation of background from low-level tritium and radon emanation in the KATRIN spectrometers

    SciTech Connect

    Leiber, B.; Collaboration: KATRIN Collaboration

    2013-08-08

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a large-scale experiment for the model independent determination of the mass of electron anti-neutrinos with a sensitivity of 200 meV/c{sup 2}. It investigates the kinematics of electrons from tritium beta decay close to the endpoint of the energy spectrum at 18.6 keV. To achieve a good signal to background ratio at the endpoint, a low background rate below 10{sup −2} counts per second is required. The KATRIN setup thus consists of a high luminosity windowless gaseous tritium source (WGTS), a magnetic electron transport system with differential and cryogenic pumping for tritium retention, and electro-static retarding spectrometers (pre-spectrometer and main spectrometer) for energy analysis, followed by a segmented detector system for counting transmitted beta-electrons. A major source of background comes from magnetically trapped electrons in the main spectrometer (vacuum vessel: 1240 m{sup 3}, 10{sup −11} mbar) produced by nuclear decays in the magnetic flux tube of the spectrometer. Major contributions are expected from short-lived radon isotopes and tritium. Primary electrons, originating from these decays, can be trapped for hours, until having lost almost all their energy through inelastic scattering on residual gas particles. Depending on the initial energy of the primary electron, up to hundreds of low energetic secondary electrons can be produced. Leaving the spectrometer, these electrons will contribute to the background rate. This contribution describes results from simulations for the various background sources. Decays of {sup 219}Rn, emanating from the main vacuum pump, and tritium from the WGTS that reaches the spectrometers are expected to account for most of the background. As a result of the radon alpha decay, electrons are emitted through various processes, such as shake-off, internal conversion and the Auger deexcitations. The corresponding simulations were done using the KASSIOPEIA framework, which has been developed for the KATRIN experiment for low-energy electron tracking, field calculation and detector simulation. The results of the simulations have been used to optimize the design parameters of the vacuum system with regard to radon emanation and tritium pumping, in order to reach the stringent requirements of the neutrino mass measurement.

  1. Prototype of an angular-selective photoelectron calibration source for the KATRIN experiment

    NASA Astrophysics Data System (ADS)

    Valerius, K.; Hein, H.; Baumeister, H.; Beck, M.; Bokeloh, K.; Bonn, J.; Glück, F.; Ortjohann, H.-W.; Ostrick, B.; Zbořil, M.; Weinheimer, Ch

    2011-01-01

    The method of direct neutrino mass determination based on the kinematics of tritium beta decay, which is adopted by the KATRIN experiment, makes use of a large, high-resolution electrostatic spectrometer with magnetic adiabatic collimation. In order to target a sensitivity on m(ν) of 0.2eV/c2, a detailed understanding of the electromagnetic properties of the electron spectrometer is essential, requiring comprehensive calibration measurements with dedicated electron sources. In this paper we report on a prototype of a photoelectron source providing a narrow energy spread and angular selectivity. Both are key properties for the characterisation of the spectrometer. The angular selectivity is achieved by applying non-parallel strong electric and magnetic fields: Directly after being created, photoelectrons are accelerated rapidly and non-adiabatically by a strong electric field before adiabatic magnetic guiding takes over.

  2. JT8D high pressure compressor performance improvement

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1981-01-01

    An improved performance high pressure compressor with potential application to all models of the JT8D engine was designed. The concept consisted of a trenched abradable rubstrip which mates with the blade tips for each of the even rotor stages. This feature allows tip clearances to be set so blade tips run at or near the optimum radius relative to the flowpath wall, without the danger of damaging the blades during transients and maneuvers. The improved compressor demonstrated thrust specific fuel consumption and exhaust gas temperature improvements of 1.0 percent and at least 10 C over the takeoff and climb power range at sea level static conditions, compared to a bill-of-material high pressure compressor. Surge margin also improved 4 percentage points over the high power operating range. A thrust specific fuel consumption improvement of 0.7 percent at typical cruise conditions was calculated based on the sea level test results.

  3. Program for refan JT8D engine design, fabrication and test, phase 2

    NASA Technical Reports Server (NTRS)

    Glass, J. A.; Zimmerman, E. S.; Scaramella, V. M.

    1975-01-01

    The objective of the JT8D refan program was to design, fabricate, and test certifiable modifications of the JT8D engine which would reduce noise generated by JT8D powered aircraft. This was to be accomplished without affecting reliability and maintainability, at minimum retrofit cost, and with no performance penalty. The mechanical design, engine performance and stability characteristics at sea-level and altitude, and the engine noise characteristics of the test engines are documented. Results confirmed the structural integrity of the JT8D-109. Engine operation was stable throughout the airplane flight envelope. Fuel consumption of the test engines was higher than that required to meet the goal of no airplane performance penalty, but the causes were identified and corrected during a normal pre-certification engine development program. Compared to the baseline JT8D-109 engine, the acoustically treated JT8D-109 engine showed noise reductions of 6 PNdB at takeoff and 11 PNdB at a typical approach power setting.

  4. A 727/JT8D-100 series engine exhaust system propulsion performance model test

    NASA Technical Reports Server (NTRS)

    Haugan, W. J.; Kern, P. R. A.

    1974-01-01

    The results are presented from testing one-eighth scale models of the Pratt and Whitney aircraft reference and Boeing nozzles for the JT8D-100 series mixed flow engines. The objective of the test was to obtain the nozzle velocity and flow coefficients for the reference configurations and compare these with the Boeing configurations which incorporated a longer splitter between the fan and primary flows. A further comparison was made between the JT8D-100 series nozzles and the Boeing JT8D-9/727 production nozzle performance. A statistical analysis was used to compare configurations which showed the performance (velocity coefficient) of the reference and the Boeing configuration was the same for the JT8D-109. It also showed no difference between reference and the Boeing configuration for the JT8D-115 and no difference for the JT8D-117 nozzles. Bypass ratio (match) was shown to be equally dependent on splitter position as on nozzle area within the range investigated. The nozzles were very similar in flow coefficient within an engine family. Excellent profile data was recorded. The effects of swirl on the nozzle performance was examined and found to degrade the velocity and flow coefficients.

  5. Control of Current Profile and Instability by Radiofrequency Wave Injection in JT-60U and Its Applicability in JT-60SA

    SciTech Connect

    Isayama, A.; Suzuki, T.; Hayashi, N.; Ide, S.; Hamamatsu, K.; Fujita, T.; Hosoyama, H.; Kamada, Y.; Oyama, N.; Ozeki, T.; Sakata, S.; Seki, M.; Sueoka, M.; Takechi, M.; Urano, H.; Nagasaki, K.

    2007-09-28

    Recent results of control of current profile and instability using radiofrequency wave in JT-60U and prediction analysis in JT-60SA are descried. In JT-60U, control of current profile in high-beta regime was demonstrated by using a real-time system, where the motional Stark effect diagnostic and lower hybrid wave were used as a detector and actuator, respectively. The minimum value of the safety factor was raised from 1.3 to 1.7 so as to follow the commanded value. Complete stabilization of a neoclassical tearing mode (NTM) with the poloidal mode number m = 2 and the toroidal mode number n = 1 was demonstrated using electron cyclotron (EC) current drive. By scanning the location of EC current drive in detail, strong stabilization effect was found for misalignment less than about half of the full island width. In addition, destabilization of the 2/1 NTM was observed for misalignment comparable to the full island width. Simulation of NTM stabilization in JT-60SA was performed by using the TOPICS code combined with the modified Rutherford equation. The TOPICS simulation showed that complete stabilization can be achieved more effectively by optimizing the EC wave injection angle and modulating the EC wave.

  6. Transient simulation of a miniature Joule-Thomson (J-T) cryocooler with and without the distributed J-T effect

    NASA Astrophysics Data System (ADS)

    Damle, R. M.; Atrey, M. D.

    2015-01-01

    The aim of this work is to develop a transient program for the simulation of a miniature Joule-Thomson (J-T) cryocooler to predict its cool-down characteristics. A one dimensional transient model is formulated for the fluid streams and the solid elements of the recuperative heat exchanger. Variation of physical properties due to pressure and temperature is considered. In addition to the J-T expansion at the end of the finned tube, the distributed J-T effect along its length is also considered. It is observed that the distributed J-T effect leads to additional cooling of the gas in the finned tube and that it cannot be neglected when the pressure drop along the length of the finned tube is large. The mathematical model, method of resolution and the global transient algorithm, within a modular object-oriented framework, are detailed in this paper. As a part of verification and validation of the developed model, cases available in the literature are simulated and the results are compared with the corresponding numerical and experimental data.

  7. Control of Current Profile and Instability by Radiofrequency Wave Injection in JT-60U and Its Applicability in JT-60SA

    NASA Astrophysics Data System (ADS)

    Isayama, A.; Suzuki, T.; Hayashi, N.; Ide, S.; Hamamatsu, K.; Fujita, T.; Hosoyama, H.; Kamada, Y.; Nagasaki, K.; Oyama, N.; Ozeki, T.; Sakata, S.; Seki, M.; Sueoka, M.; Takechi, M.; Urano, H.

    2007-09-01

    Recent results of control of current profile and instability using radiofrequency wave in JT-60U and prediction analysis in JT-60SA are descried. In JT-60U, control of current profile in high-beta regime was demonstrated by using a real-time system, where the motional Stark effect diagnostic and lower hybrid wave were used as a detector and actuator, respectively. The minimum value of the safety factor was raised from 1.3 to 1.7 so as to follow the commanded value. Complete stabilization of a neoclassical tearing mode (NTM) with the poloidal mode number m = 2 and the toroidal mode number n = 1 was demonstrated using electron cyclotron (EC) current drive. By scanning the location of EC current drive in detail, strong stabilization effect was found for misalignment less than about half of the full island width. In addition, destabilization of the 2/1 NTM was observed for misalignment comparable to the full island width. Simulation of NTM stabilization in JT-60SA was performed by using the TOPICS code combined with the modified Rutherford equation. The TOPICS simulation showed that complete stabilization can be achieved more effectively by optimizing the EC wave injection angle and modulating the EC wave.

  8. B747/JT9D flight loads and their effect on engine running clearances and performance deterioration; BCAC NAIL/P and WA JT9D engine diagnostics programs

    NASA Technical Reports Server (NTRS)

    Olsson, W. J.; Martin, R. L.

    1982-01-01

    Flight loads on the 747 propulsion system and resulting JT9D blade to outer airseal running clearances during representative acceptance flight and revenue flight sequences were measured. The resulting rub induced clearance changes, and engine performance changes were then analyzed to validate and refine the JT9D-7A short term performance deterioration model.

  9. Absolute calibration of microfission chamber in JT-60U

    SciTech Connect

    Hayashi, Takao; Nishitani, Takeo; Sukegawa, Atsuhiko M.; Ishikawa, Masao; Shinohara, Kouji

    2008-10-15

    We have conducted calibrations of a microfission chamber, which was installed between the vacuum vessel and the toroidal field coils, by both a Cf-252 neutron source and real deuterium plasmas in JT-60U. The detector employs both pulse counting and Campbell (mean square voltage) modes in the electronics to cover a wide dynamic range of the neutron source strength. The pulse counting and Campbell modes were calibrated by Cf-252 and deuterium plasmas, respectively. Point efficiencies, counts per neutron from a point at a single angle, were measured for 27 locations of the neutron point source in toroidal scan. The efficiencies were influenced by the various components such as the vacuum vessel, port, and graphite tiles. The point efficiencies can be integrated and averaged with angle to provide toroidal line efficiencies. The line efficiencies of the microfission chamber and the nearest neutron monitor of the U-235 fission chamber were 5.38x10{sup -9} and 1.77x10{sup -8}, respectively. Then the calibration for the Campbell mode was also performed by using a real deuterium plasma. The detection efficiency in the Campbell mode was about three-tenths of that of the nearest neutron monitor, which is consistent with the calibration result obtained by using a Cf-252 neutron source for pulse counting mode.

  10. Oxygen chemisorption compressor study for cryogenic J-T refrigeration

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Blue, Gary D.

    1987-01-01

    Over twenty potentially reversible heat-powered oxide reactions have been studied and/or tested to determine their potential use as thermochemical oxygen compressors for cryogenic J-T LO2 refrigerators. One gas-solid compound family, Pr(1-n)Ce(n)O(x), proved to be completely reversible with fast kinetics for all pressure ranges tested below 650 C. With a heat-powered charcoal/methane physical adsorption upper stage and a Pr(1-n)Ce(n)O(x) chemisorption lower stage, temperatures should be attainable in the 55-80 K range for less power and over five times less weight than for charcoal/nitrogen sorption refrigeration systems. Total system power requirements with a hydride chemisorption lower stage (10 K to 7 K minimum) are about three times less than any mechanical refrigerator, and spacecraft refrigeration weights are about twenty times less. Due to the lack of wear-related moving parts in sorption refrigerators, life expectancy is at least ten years, and there essentially no vibration.

  11. Preliminary Studies of the JT-60SA Cryogenic System

    NASA Astrophysics Data System (ADS)

    Lamaison, V.; Balaguer, D.; Gros, G.; Hoa, C.; Marchal, J. L.; Michel, F.; Reynaud, P.; Roussel, P.; Wanner, M.

    2010-04-01

    For the superconducting tokamak JT-60SA, one of the major projects within the Broader Approach Agreement between Europe and Japan, CEA is in charge of the cryoplant system. Preliminary studies were performed in order to prepare the specifications. The presentation focuses on the modelling of two operating modes, the baking and the cool down, and on a study of the economics of the electrical power distribution of the warm compression station. Baking mode consists in heating the vacuum vessel to 473 K during several days to "clean" surfaces. Because of the increased radiation heat loads from the vacuum vessel on the thermal shields, the helium mass flow at 80 K has to be increased by 50%. To avoid designing the cryogenic plant for this occasional overload, different scenarios were studied. During cool down mode, the mass flows have been calculated to ensure the required cool down speed. The limiting factors are the pressure drop in the coil windings and the magnet cool down speed. The warm compressor station represents a large part of the investment cost and is the main consumer of electrical power of the cryogenic system. Different compressors and motors have been analysed to optimise power consumption vs. investment costs.

  12. Cryogenic thermometry for refrigerant distribution system of JT-60SA

    NASA Astrophysics Data System (ADS)

    Natsume, K.; Murakami, H.; Kizu, K.; Yoshida, K.; Koide, Y.

    2015-12-01

    JT-60SA is a fully superconducting fusion experimental device involving Japan and Europe. The cryogenic system supplies supercritical or gaseous helium to superconducting coils through valve boxes or coil terminal boxes and in-cryostat pipes. There are 86 temperature measurement points at 4 K along the distribution line. Resistance temperature sensors will be installed on cooling pipes in vacuum. In this work, two sensor attachment methods, two types of sensor, two thermal anchoring methods, and two sensor fixation materials have been experimentally evaluated in terms of accuracy and mass productivity. Finally, the verification test of thermometry has been conducted using the sample pipe fabricated in the same way to the production version, which has been decided by the comparison experiments. The TVO sensor is attached by the saddle method with Apiezon N grease and the measurement wires made of phosphor bronze are wound on the pipe with Stycast 2850FT as the thermal anchoring. A Cernox sensor is directly immersed in liquid helium as a reference thermometer during the experiment. The measured temperature difference between the attached one and reference one has been within ±15 mK in the range of 3.40-4.73 K. It has satisfies the accuracy requirement of 0.1 K.

  13. Performance analysis of a miniature Joule-Thomson cryocooler with and without the distributed J-T effect

    NASA Astrophysics Data System (ADS)

    Damle, Rashmin; Atrey, Milind

    2015-12-01

    Cryogenic temperatures are obtained with Joule-Thomson (J-T) cryocoolers in an easier way as compared to other cooling techniques. Miniature J-T cryocoolers are often employed for cooling of infrared sensors, cryoprobes, biological samples, etc. A typical miniature J-T cryocooler consists of a storage reservoir/compressor providing the high pressure gas, a finned tube recuperative heat exchanger, an expansion valve/orifice, and the cold end. The recuperative heat exchanger is indispensable for attaining cryogenic temperatures. The geometrical parameters and the operating conditions of the heat exchanger drastically affect the cryocooler performance in terms of cool down time and cooling effect. In the literature, the numerical models for the finned recuperative heat exchanger have neglected the distributed J-T effect. The distributed J-T effect accounts for the changes in enthalpy of the fluid due to changes of pressure in addition to those due to changes of temperature. The objective of this work is to explore the distributed J-T effect and study the performance of a miniature J-T cryocooler with and without the distributed J-T effect. A one dimensional transient model is employed for the numerical analysis of the cryocooler. Cases with different operating conditions are worked out with argon and nitrogen as working fluids.

  14. High power operation of Gaussian beam gyrotron with CVD diamond window for JT-60U

    SciTech Connect

    Kasugai, Atsushi; Takahashi, Koji; Sakamoto, Keishi; Ikeda, Yukiharu; Ikeda, Yoshitaka; Tsuneoka, Masaki; Kariya, Tsuyoshi; Mitsunaka, Yoshika; Imai, Tsuyoshi

    1999-09-20

    A 110 GHz-Gaussian beam output gyrotron with CVD (Chemical Vapor Deposition) diamond window was developed for the electron cyclotron heating and current drive on JT-60U. A stable Gaussian output beam power of 1.1 MW-0.1 s was obtained with the efficiency of 39% with depressed collector operation. Due to Gaussian beam output from the gyrotron, the coupling efficiency to HE11 mode in the mirror optical unit was 94%. Moreover, the transmission efficiency of 89% for HE11 mode was performed at the power level of 1 MW on the 40 m-transmission test line of {phi}31.751 mm corrugated waveguide and 8-miter bends included 1-pair of polarizer. The gyrotron and transmission line were installed into JT-60U system and 0.6 MW-0.3 s power was successfully injected into JT-60U plasmas as an initial operation.

  15. Pollution reduction technology program for class T4(JT8D) engines

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Fiorentino, A. J.; Diehl, L. A.

    1977-01-01

    The technology required to develop commercial gas turbine engines with reduced exhaust emissions was demonstrated. Can-annular combustor systems for the JT8D engine family (EPA class T4) were investigated. The JT8D turbofan engine is an axial-flow, dual-spool, moderate-bypass-ratio design. It has a two-stage fan, a four-stage low-pressure compressor driven by a three-stage low-pressure turbine, and a seven-stage high-pressure compressor driven by a single-stage high-pressure turbine. A cross section of the JT8D-17 showing the mechanical configuration is given. Key specifications for this engine are listed.

  16. Summary and analysis of performance and stability characteristics of the refan JT8D-109 engine

    NASA Technical Reports Server (NTRS)

    Sanberg, K. G.; Mogielnicki, R. M.; Davis, J. C.; Scaramella, V. M.

    1975-01-01

    The refan JT8D-109 performance and stability characteristics are reported as determined from sea level testing, altitude testing, and DC-9 flight testing. The test results are summarized as follows: (1) TSFC at SLS achieved design goal of 12.66 percent reduction. (2) TSFC at altitude average cruise power 0.5 percent higher than design goal, (3) TSFC at altitude maximum cruise power 1.7-3.7 percent higher than design goal, (4) ground starting consistent with JT8D-9 base engine, (5) successful flight starts without starter assist, (6) transient surge margin equivalent to JT8D-9, (7) stable engine operation with inlet distortion, and (8) stable engine operation during snap acceleration and deceleration. A flight idle setting is required for acceptable aborted-landing go-around acceleration time due to increase in low-rotor moment of inertia, and a performance improvement program should be conducted as part of any future certification program.

  17. Atomization and combustion characteristics of antimisting fuels using JT8D and air-boost injectors

    NASA Technical Reports Server (NTRS)

    Kennedy, J. B.; Florentino, A. J.

    1986-01-01

    The atomization levels of antimisting fuels are presently determined for a JT8D fuel injector, a low emission airblast JT8D injector, and an air-boost injector, at operating conditions simulating engine operating conditions. The effects of the use of antimisting kerosene (AMK) on component performance are also studied in the case of an in-service JT8D engine. The use of the AMK fuel causes a decline in the quality of the spray, most notably as a large increase in the Sauter mean diameter for all three injector types. In addition, the idle patternation data obtained indicate that the low emission injector fuel distribution changed from a hollow cone Jet A spray having no fuel at its center to a semihollow spray cone in the case of AMK; this change could disrupt the combustor primary zone recirculation pattern.

  18. Development of the Hybrid Jt-Expander Cycle for NG Liquefaction Cycle

    NASA Astrophysics Data System (ADS)

    Baek, S.; Hwang, G.; Jeong, S.

    2010-04-01

    Two liquefaction cycles for LNG (liquefied natural gas) production are compared in this paper. One is a well known MR (mixed refrigerant) JT cycle with two phase separators and four heat exchangers. Another one is the novel concept of hybrid cycle, which is to replace the last stage JT expansion with a turbine expander. The inlet flow to the turbine expander is deliberately warmed up by NG (natural gas) stream to guarantee superheated vapor phase and increase useful work. The turbine expander is to extract pressure exergy and reduce entropy generation by producing work and alleviating work requirement in the compressor. This paper describes the detailed processes of hybrid JT-expander cycle and the quantitative comparison results by HYSYS simulation under some realistic physical constraints.

  19. Next generation KATRIN high precision voltage divider for voltages up to 65kV

    NASA Astrophysics Data System (ADS)

    Bauer, S.; Berendes, R.; Hochschulz, F.; Ortjohann, H.-W.; Rosendahl, S.; Thümmler, T.; Schmidt, M.; Weinheimer, C.

    2013-10-01

    The KATRIN (KArlsruhe TRItium Neutrino) experiment aims to determine the mass of the electron antineutrino with a sensitivity of 200 meV by precisely measuring the electron spectrum of the tritium beta decay. This will be done by the use of a retarding spectrometer of the MAC-E-Filter type. To achieve the desired sensitivity the stability of the retarding potential of -18.6 kV has to be monitored with a precision of 3 ppm over at least two months. Since this is not feasible with commercial devices, two ppm-class high voltage dividers were developed, following the concept of the standard divider for DC voltages of up to 100 kV of the Physikalisch-Technische Bundesanstalt (PTB). In order to reach such high accuracies different effects have to be considered. The two most important ones are the temperature dependence of resistance and leakage currents, caused by insulators or corona discharges. For the second divider improvements were made concerning the high-precision resistors and the thermal design of the divider. The improved resistors are the result of a cooperation with the manufacturer. The design improvements, the investigation and the selection of the resistors, the built-in ripple probe and the calibrations at PTB will be reported here. The latter demonstrated a stability of about 0.1 ppm/month over a period of two years.

  20. Development of a cryogenic mixed fluid J-T cooling computer code, 'JTMIX'

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1991-01-01

    An initial study was performed for analyzing and predicting the temperatures and cooling capacities when mixtures of fluids are used in Joule-Thomson coolers and in heat pipes. A computer code, JTMIX, was developed for mixed gas J-T analysis for any fluid combination of neon, nitrogen, various hydrocarbons, argon, oxygen, carbon monoxide, carbon dioxide, and hydrogen sulfide. When used in conjunction with the NIST computer code, DDMIX, it has accurately predicted order-of-magnitude increases in J-T cooling capacities when various hydrocarbons are added to nitrogen, and it predicts nitrogen normal boiling point depressions to as low as 60 K when neon is added.

  1. Minimization of Reactive Power Fluctuation in JT-60SA Magnet Power Supply

    NASA Astrophysics Data System (ADS)

    Shimada, K.; Terakado, T.; Yamauchi, K.; Matsukawa, M.; Baulaigue, O.; Coletti, R.; Coletti, A.; Novello, L.

    2013-02-01

    This paper describes an asymmetric control method for the firing angle and a start/stop timing shift control of four thyristor converters called “Booster PS" to minimize the reactive power fluctuation during plasma initiation in JT-60SA. From the simulation using the “PSCAD/EMTDC" code, it is found that these control methods can drastically reduce the reactive power induced by the four units of the “Booster PS". In addition, the voltage fluctuation of the motor-generator connected to the “Booster PS" is expected to be suppressed. This can also contribute to achieve stable control of the JT-60SA magnet power supplies.

  2. Long-pulse hybrid scenario development in JT-60U

    NASA Astrophysics Data System (ADS)

    Oyama, N.; Isayama, A.; Matsunaga, G.; Suzuki, T.; Takenaga, H.; Sakamoto, Y.; Nakano, T.; Kamada, Y.; Ide, S.; JT-60 Team

    2009-06-01

    The performance and sustained duration of long-pulse discharges for the 'ITER hybrid scenario' have been improved in JT-60U. The modification of power supply systems for three perpendicular neutral beam (NB) injections provides a long period of central NB heating up to 30 s, which is important for keeping the internal transport barrier (ITB). The peaked density profile in the core plasma can be maintained even when the density at the pedestal increased in the latter phase of the discharge due to the increase in the divertor recycling. Then, the peaked pressure profile attributed to the ITB can be kept constant through the discharge with the peaked power deposition profile. In these long-pulse discharges, MHD activity with toroidal mode number n = 1 is observed even when neoclassical tearing modes (NTMs) are suppressed. When the amplitude of the mode in the peripheral region becomes large, the pedestal pressure is degraded. The mode amplitude is sensitive to the toroidal magnetic field (or edge safety factor) and heating power. After the adjustment of the toroidal magnetic field so as to reduce the mode amplitude, a high normalized beta (βN) of 2.6 and a high thermal confinement enhancement factor (HH98(y,2) > 1) are sustained for 25 s (~14τR, where τR is the current diffusion time) under the ITER relevant small toroidal rotation condition. The peaked pressure profile in low safety factor plasma (safety factor at 95% flux surface q95 ~ 3.2) is stable against NTMs up to βN ~ 3. A high βNHH98(y,2) of 2.6 gives a high G-factor ( \\beta_NH_H98(y,2)/q_95^{2} ) of 0.25 and a peaked pressure profile gives a large bootstrap current fraction (fBS > 0.43).

  3. DC-9 flight demonstration program with refanned JT8D engines. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The design, analysis, fabrication, and ground and flight testing of DC-9 airframe/nacelle hardware with prototype JT8D-109 engines are discussed. The installation of the JT8D-109 engine on the DC-9 Refan airplane required new or modified hardware for the pylon, nacelle, and fuselage. The acoustic material used in the nose cowl was bonded aluminum honeycomb sandwich and the exhaust duct acoustic material was Inconel 625 Stresskin. The sea level static, standard day bare engine takeoff thrust, the cruise TSFC and the maximum available cruise thrust for the JT8D-109 engine were compared with those of the JT8D-9 engine. The range capabilities of the DC-9 Refan and the production DC-9 airplane were also compared. The Refan airplane demonstrated flight characteristics similar to the production DC-9-30 and satisfied airworthiness requirements. Flyover noise levels were determined for the DC-9 Refan and the DC-9 C-9A airplane for takeoff and landing conditions. Cost estimates were also made.

  4. Mixed-refrigerant Joule-Thomson (MR JT) mini-cryocoolers

    NASA Astrophysics Data System (ADS)

    Tzabar, Nir

    2014-01-01

    This paper presents the progress in our ongoing research on Mixed-Refrigerant (MR) Joule-Thomson (JT) cryocoolers. The research begun by exploring different MRs and testing various compressors: oil-lubricated and oil-free, reciprocating and linear, custom-made and commercial. Closed-cycle JT cryocoolers benefit from the fact that the compressor might be located far from the cold-end and thus there are no moving parts, no vibrations, and no heat emission near the cold-end. As a consequence, the compressor may be located where there are no severe size limitations, its heat can be conveniently removed, and it can be easily maintained. However, in some applications there is still a demand for a small compressor to drive a JT cryocooler although it is located far from the cooled device. Recently, we have developed a miniature oil-free compressor for MR JT cryocoolers that weighs about 700 g and its volume equals about 300 cc. The cryocooler operates with a MR that contains Ne, N2, and Hydrocarbons. This MR has been widely investigated with different compressors and varying operating conditions and proved to be stable. The current research investigates the performances of MR JT mini-cryocooler operating with the MR mentioned above, driven with our miniature compressor, and a cold-finger prototype. A Dewar with heat load of about 230 mW is cooled to about 80 K at ambient temperatures between 0°C and 40°C. The experimental results obtained are stable and demonstrate the ability to control the cooling temperature by changing the rotation speed of the compressor.

  5. Passive coolers for pre-cooling of JT loops for deep space infrared imaging applications

    NASA Astrophysics Data System (ADS)

    Zhang, Burt; Larson, Melora; Rodriguez, Jose

    2010-09-01

    Infrared instruments (IR) for deep space imaging missions, such as the James Webb Space Telescope (JWST) and Planck, require cryogenic cooling for proper operation of their focal plane arrays (FPA) in far infrared and sub-millimeter wavelength ranges. The FPA is sometimes located meters away from the spacecraft. To meet such remote cooling requirement, a Joule-Thomson (J-T) loop becomes a convenient choice for either direct cooling for the FPA or for serving as a heat sink for a cascade cooling system. The refrigerant lines of the JT loop inevitably suffer parasitic heat leak primarily due to IR backload as they traverse from the spacecraft to the FPA. An actively cooled JT loop using a mechanical pre-cooler located at the spacecraft will experience the highest parasitic heat leak since the lines are cold through the entire length whereas a passively cooled JT loop can utilize a number of radiators to cool the lines down gradually in stages and hence reduce the heat leak. In addition to savings in power and mass, a passive cooler offers consistent and predictable performance with practically no performance degradation in a thermally stable orbit, such as one around the Sun-Earth L2 point. Passive coolers are less popular in low temperature applications when their cooling capacity diminishes rapidly in proportion to T4 until the temperature reaches a point where either the parasitic heat leak becomes so significant or its size becomes so excessive that the passive cooling scheme becomes impractical. Despite the limited capacity, passive cooling may still prove to be a viable alternative to active cooling depending on the operating temperature and heat dissipation rate of the FPA. The current effort aims at evaluating the merit of using passive coolers as an alternative to using a mechanical cooler for pre-cooling of a JT loop for remote IR instrument cooling. A parametric study is conducted to explore the merits of passive cooling of a JT loop in a temperature range below 30 K. Correlations between cooling capacity, heat leak from supporting structure, and the operating temperature are investigated to provide design guidelines. Radiator staging options will also be presented and discussed.

  6. 75 FR 62319 - Airworthiness Directives; Pratt & Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-08

    ...; AD 2010-21-17] RIN 2120-AA64 Airworthiness Directives; Pratt & Whitney JT8D-9, -9A, -11, -15, -17.... SUMMARY: The FAA is adopting a new airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-9, -9A, -11... to PW JT8D-9, -9A, -11, - 15, -17, and -17R turbofan engines. We published the proposed AD in...

  7. Tritium Recovery at Fusion Facility 4.Tritium Experience in JT-60 Operation

    NASA Astrophysics Data System (ADS)

    Oikawa, Akira; Miya, Naoyuki

    The tritium effluent of JT-60 vacuum exhaust through the stack and into the environment always remains below the detectable level. Tritium concentration in the drain water is below a limit of regulation by the local agreement and the law, though small tritium contamination in facility drains and in rain drains of the stack has occasionally been detected. Following an annual deuterium plasma discharge campaign, a 4-week hydrogen or helium plasma discharge campaign and subsequent ventilation of room air reduced the tritium concentration on the surface of in-vessel components back to ground level and then the in-vessel was ready for the maintenance. A cooperative endeavor is underway to complete an analysis of tritium behaviors in JT-60.

  8. Engine component improvement: Performance improvement, JT9D-7 3.8 AR fan

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1980-01-01

    A redesigned, fuel efficient fan for the JT9D-7 engine was tested. Tests were conducted to determine the effect of the 3.8 AR fan on performance, stability, operational characteristics, and noise of the JT9D-7 engine relative to the current 4.6 AR Bill-of-Material fan. The 3.8 AR fan provides increased fan efficiency due to a more advanced blade airfoil with increased chord, eliminating one part span shroud and reducing the number of fan blades and fan exit guide vanes. Engine testing at simulated cruise conditions demonstrated the predicted 1.3 percent improvement in specific fuel consumption with the redesigned 3.8 AR fan. Flight testing and sea level stand engine testing demonstrated exhaust gas temperature margins, fan and low pressure compressor stability, operational suitability, and noise levels comparable to the Bill-of-Material fan.

  9. Finite element-integral acoustic simulation of JT15D turbofan engine

    NASA Technical Reports Server (NTRS)

    Baumeister, K. J.; Horowitz, S. J.

    1984-01-01

    An iterative finite element integral technique is used to predict the sound field radiated from the JT15D turbofan inlet. The sound field is divided into two regions: the sound field within and near the inlet which is computed using the finite element method and the radiation field beyond the inlet which is calculated using an integral solution technique. The velocity potential formulation of the acoustic wave equation was employed in the program. For some single mode JT15D data, the theory and experiment are in good agreement for the far field radiation pattern as well as suppressor attenuation. Also, the computer program is used to simulate flight effects that cannot be performed on a ground static test stand.

  10. Summary of TFTR (Tokamak Fusion Test Reactor) diagnostics, including JET (Joint European Torus) and JT-60

    SciTech Connect

    Hill, K.W.; Young, K.M.; Johnson, L.C.

    1990-05-01

    The diagnostic instrumentation on TFTR (Tokamak Fusion Test Reactor) and the specific properties of each diagnostic, i.e., number of channels, time resolution, wavelength range, etc., are summarized in tables, grouped according to the plasma parameter measured. For comparison, the equivalent diagnostic capabilities of JET (Joint European Torus) and the Japanese large tokamak, JT-60, as of late 1987 are also listed in the tables. Extensive references are given to publications on each instrument.

  11. Status of the KATRIN experiment and prospects to search for keV-mass sterile neutrinos in tritium β-decay

    SciTech Connect

    Mertens, Susanne

    2015-03-24

    In this contribution the current status and future perspectives of the Karlsruhe Tritium Neutrino (KATRIN) Experiment are presented. The prime goal of this single β-decay experiment is to probe the absolute neutrino mass scale with a sensitivity of 200 meV (90% CL). We discuss first results of the recent main spectrometer commissioning measurements, successfully verifying the spectrometer’s basic vacuum, transmission and background properties. We also discuss the prospects of making use of the KATRIN tritium source, to search for sterile neutrinos in the multi-keV mass range constituting a classical candidate for Warm Dark Matter. Due to the very high source luminosity, a statistical sensitivity down to active-sterile mixing angles of sin² θ < 1 · 10⁻⁷ (90% CL) could be reached.

  12. Status of the KATRIN experiment and prospects to search for keV-mass sterile neutrinos in tritium β-decay

    DOE PAGESBeta

    Mertens, Susanne

    2015-03-24

    In this contribution the current status and future perspectives of the Karlsruhe Tritium Neutrino (KATRIN) Experiment are presented. The prime goal of this single β-decay experiment is to probe the absolute neutrino mass scale with a sensitivity of 200 meV (90% CL). We discuss first results of the recent main spectrometer commissioning measurements, successfully verifying the spectrometer’s basic vacuum, transmission and background properties. We also discuss the prospects of making use of the KATRIN tritium source, to search for sterile neutrinos in the multi-keV mass range constituting a classical candidate for Warm Dark Matter. Due to the very high sourcemore » luminosity, a statistical sensitivity down to active-sterile mixing angles of sin² θ < 1 · 10⁻⁷ (90% CL) could be reached.« less

  13. First measurement of time-resolved neutron yield on JT-60U using a microfission chamber

    NASA Astrophysics Data System (ADS)

    Hayashi, T.; Nishitani, T.; Ishikawa, M.

    2004-10-01

    Microfission chambers, which are pencil sized ionization chamber containing fissile material inside, will be installed in the vacuum vessel as neutron monitors for International Thermonuclear Experimental Reactor (ITER). We have performed first measurements of the detector installed between the vacuum vessel and toroidal coils on JT-60U. The technical validity as a neutron monitor, such as magnetic field effect and electromagnetic noises from the plasma and heating devices, has been investigated. The detector had an excellent linearity with a 235U fission chamber as a neutron monitor on JT-60U with the standard deviation of 3% except for some noise signals. The electromagnetic noises were caused by neutral beam injection (NBI) breakdowns, probably due to long wiring between the detector and the preamplifier. In case of plasma disruption, improper signals have not been observed. The magnetic field effect also has not been observed up to 2 T. In JT-60U, we confirmed availability of the micro fission chamber as a neutron monitor over three decades of neutron source strength up to 1.3×1016 neutrons/s with 1 ms temporal resolution. The biggest weakness in the detector was its noise sensitivity to NBI breakdowns. Therefore, by suppressing the electromagnetic noise, microfission chambers can be available as neutron monitors for ITER.

  14. Effect of time dependent flight loads on JT9D-7 performance deterioration

    NASA Technical Reports Server (NTRS)

    Jay, A.; Lewis, B. L.

    1979-01-01

    The results of a modal transient analysis of the engine/aircraft system are presented. The response of the JT9D to analytically simulated vertical gusts and landings was predicted using a NASTRAN finite element mathematical model of the JT9D/747 propulsion system. The NASTRAN finite element model of the propulsion system included engine structural models of the fan, low/high pressure compressors, diffuser/turbine cases, and high/low pressure rotors, as well as nacelle models of the inlet cowl, tailcone, and wing pylon. The analysis conducted predicts that an insignificant level of JT9D-7 performance deterioration would occur due to a typical vertical gust encounter or a typical revenue service landing. Analysis of a high sink rate landing with a heavy fuel load indicates the possibility of local wear, however, the lack of an accurate dynamic rotor/seal interference model precludes an accurate quantitative evaluation of performance change for this once-per-airframe-life event.

  15. Conceptual Design of Divertor Cassette Handling by Remote Handling System of JT-60SA

    NASA Astrophysics Data System (ADS)

    Hayashi, Takao; Sakurai, Shinji; Masaki, Kei; Tamai, Hiroshi; Yoshida, Kiyoshi; Matsukawa, Makoto

    The JT-60SA aims to contribute and supplement ITER toward demonstration fusion reactor based on tokamak concept. One of the features of JT-60SA is its high power long pulse heating, causing the large annual neutron fluence. Because the expected dose rate at the vacuum vessel (VV) may exceed 1 mSv/hr after 10 years operation and three month cooling, the human access inside the VV is restricted. Therefore a remote handling (RH) system is necessary for the maintenance and repair of in-vessel components. This paper described the RH system of JT-60SA, especially the expansion of the RH rail and exchange of the divertor cassettes. The RH rail is divided into nine and three-point mounting. The nine sections can cover 225 degrees in toroidal direction. A divertor cassette, which is 10 degrees wide in toroidal direction and weighs 500kg itself due to the limitations of port width and handling weight, can be exchanged by heavy weight manipulator (HWM). The HWM brings the divertor cassette to the front of the other RH port, which is used for supporting the rail and/or carrying in and out equipments. Then another RH device receives and brings out the cassette by a pallet installed from outside the VV.

  16. Simulation of the Effect of Plasma Flows in DIII-D, JET, and JT-60U

    SciTech Connect

    Porter, G D; Rognlien, T D; Rensink, M E; Loarte, A; Asakura, N; Takenaga, H; Mathews, G

    2002-05-17

    The results of 2D fluid plasma simulations of the ion flow in the boundary plasma of DIII-D, JET, and JT-60U are reported. The model includes the effects of drifts and of impurity radiation using a multi-species model of intrinsic carbon impurities. Drift effects are important in determining the primary and impurity ion fluxes in the SOL and the private region, with ExB drifts dominant. Simulated parallel velocities are consistent with experimental measurement on the high field side of JT-60U, where the parallel flow is determined by ion sources. Simulated parallel velocities are significantly less than seen in experiment at the outer midplane of JT-60U, and at the top of JET where the flow is sensitive to poloidal variations of the turbulence driven transport, suggesting the velocity in these regions is determined by transport. Parallel flows are reversed by changing the direction of the ion VB drift relative to the X-point.

  17. Understanding of the fundamental differences in JET and JT-60U AT discharges

    NASA Astrophysics Data System (ADS)

    Sirén, P.; Tala, T.; Corrigan, G.; Garcia, J.; Koskela, T.; Köchl, F.; Litaudon, X.; Salmi, A.; EFDA contributors, JET; the EU-ITM ITER Scenario Modelling Group

    2015-07-01

    Plasma current density simulations of JET and JT-60U shots in reverse-q advanced scenarios based on the previous data analysis of the identity plasma experiments have been performed. The effects of the main differences between the shots (neutral beam current density (jnbi), electron density and geometry) have been studied. The reversed q-profile (which was the target in this identity experiment and is observed at the beginning of each shot) was sustained in JT-60U while it became flat in JET towards the end of the shot. In JET, jnbi is peaked on-axis whereas in JT-60U it is peaked off-axis (at ρ = 0.5) while the NBI fraction of the selected shots is the same (22-24%). A strong density ITB appeared (at ρ = 0.5) in JT-60U but not in JET. The plasma geometry was mainly set to match but it was not identical. In addition, the extrapolation to JET steady-state operation has been done by testing the sensitivity of q to different externally driven currents, electron density and geometry in predictive current diffusion simulations. Moreover, critical bootstrap current density has been analysed. The reasons for the different time evolution of q-profile have been studied with predictive current simulations with the 1.5D transport code JETTO. The current diffusion model was validated against reverse-q shots, and simulations were performed with experimental data profiles, jNBI given by ASCOT and neoclassical resistivity and bootstrap current calculated by NCLASS. Bootstrap current density was the most efficient way to sustain the beneficial reverse shape of q-profile. Replacing the JET ne profile with one from JT-60U leads to an increase of 0.2-0.3 MA in the bootstrap current (f bs increases from 15% to 30%). However, sustaining the stationary reverse q is not achieved in JET with bootstrap current induced by the density gradient of JT-60U. Even 10 times larger gradient than in JT-60U helps to sustain the shape of the q-profile longer than the experimentally observed density profile in JET but the minimum value of q moves closer to central plasma and the shape of q is not stationary in a 10 s simulation. The effect of different shape of NBI current density profile is negligible due to quite small fraction. Sustaining the reverse q requires 45% or larger added off-axis fraction. However, increasing the inverse aspect ratio increases bootstrap current and decreases the critical bootstrap current more effectively than increasing the density gradient: two times larger inverse aspect ratio produces almost three times larger bootstrap fraction but ten times larger density gradient only two times larger bootstrap fraction. The conclusions based on these simulations indicate that the need for bootstrap current is larger in JET and the same conditions cause smaller bootstrap fraction, which suggests that achieving steady-state operation in JET under these conditions is unlikely.

  18. Progress in long-pulse production of powerful negative ion beams for JT-60SA and ITER

    NASA Astrophysics Data System (ADS)

    Kojima, A.; Umeda, N.; Hanada, M.; Yoshida, M.; Kashiwagi, M.; Tobari, H.; Watanabe, K.; Akino, N.; Komata, M.; Mogaki, K.; Sasaki, S.; Seki, N.; Nemoto, S.; Shimizu, T.; Endo, Y.; Ohasa, K.; Dairaku, M.; Yamanaka, H.; Grisham, L. R.

    2015-06-01

    Significant progress in the extension of pulse durations of powerful negative ion beams has been made to realize the neutral beam injectors for JT-60SA and ITER. In order to overcome common issues of the long-pulse production/acceleration of negative ion beams in JT-60SA and ITER, new technologies have been developed in the JT-60SA ion source and the MeV accelerator in Japan Atomic Energy Agency. As for the long-pulse production of high-current negative ions for the JT-60SA ion source, the pulse durations have been successfully increased from 30 s at 13 A on JT-60U to 100 s at 15 A by modifying the JT-60SA ion source, which satisfies the required pulse duration of 100 s and 70% of the rated beam current for JT-60SA. This progress was based on the R&D efforts for the temperature control of the plasma grid and uniform negative ion productions with the modified tent-shaped filter field configuration. Moreover, each parameter of the required beam energy, current and pulse has been achieved individually by these R&D efforts. The developed techniques are useful to design the ITER ion source because the sustainment of the caesium coverage in the large extraction area is one of the common issues between JT-60SA and ITER. As for the long-pulse acceleration of high power density beams in the MeV accelerator for ITER, the pulse duration of MeV-class negative ion beams has been extended by more than 2 orders of magnitude by modifying the extraction grid with a high cooling capability and a high transmission of negative ions. A long-pulse acceleration of 60 s has been achieved at 70 MW m-2 (683 keV, 100 A m-2) which has reached the power density of JT-60SA level of 65 MW m-2. No degradations of the voltage holding capability of the acceleration voltage and the beam optics due to the distortion of the acceleration grids have been observed in this power density level. These results are the longest pulse durations of high-current and high-power-density negative ion beams in the world.

  19. 75 FR 27972 - Airworthiness Directives; Pratt & Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-19

    ... Register published on April 11, 2000 (65 FR 19477-78). Examining the AD Docket You may examine the AD... JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-9, -9A, -11, -15, -17, and -17R turbofan...

  20. 75 FR 3217 - J&T Hydro Company; H. Dean Brooks and W. Bruce Cox; Notice of Application for Transfer of License...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission J&T Hydro Company; H. Dean Brooks and W. Bruce Cox; Notice of Application for Transfer of License and Soliciting Comments and Motions To Intervene January 12, 2010. On October 30, 2009, J&T Hydro Company (transferor)...

  1. Phase 2 program on ground test of refanned JT8D turbofan engines and nacelles for the 727 airplane. Volume 3: Ground tests

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The NASA Refan Program included full-scale performance and noise ground tests of both a current production (JT8D-15) and a refanned (JT8D-115) engine. A description of the two ground tests including detailed propulsion, noise, and structural test results is presented. The primary objectives of the total test program were comparison of JT8D-15 and JT8D-115 overall propulsion system performance and noise characteristics and determination of incremental component noise levels. Other objectives of the test program included: (1) determination of acoustic treatment effectiveness; (2) measurement of internal sound pressure levels; (3) measurement of inlet and exhaust hardware performance; (4) determination of center-engine surge margin; and (5) evaluation of certain structural characteristics associated with the 727 refan center-engine inlet duct and JT8D refan engine exhaust system. The JT8D-15 and -115 tests were conducted during September 1974 and January to March 1975, respectively. Analyses of the test data indicated that the JT8D-115, as compared to the JT8D-15, demonstrates a 12.5 percent to 13.2 percent reduction in static specific fuel consumption, and a reduction of 6 to 7 PNdB in a weighted average value of static tone corrected perceived noise level. Separated into noise components, a significant reduction was shown for the inlet fan, aft fan, exhaust duct flow, turbine, and jet noises. However, core noise was increased. Photographs of test stands and test equipment are shown.

  2. Research and Development of 2-frequency (110/138 GHz) FADIS for JT-60SA ECHCD system

    NASA Astrophysics Data System (ADS)

    Idei, H.; Moriyama, S.; Kobayashi, T.; Isayama, A.; Sakaguchi, M.; Kasparek, W.

    2015-03-01

    A FAst DIrectional Switch (FADIS) of 2-frequency (2-ƒ) gyrotron system for the JT-60SA project is being developed under collaboration between Japan Atomic Energy Agency (JAEA) and Kyushu University. At first, the frequency drift and dip in the gyrotron operation were measured to consider which kind of FADIS is preferred for application in the Electron Cyclotron Heating and Current Drive (ECHCD) system for the JT- 60SA. Various types of the FADIS have been considered. A square corrugated waveguide diplexer system with double resonant rings was considered as one of the most attractive FADIS systems for stable high-power and long-pulse operations in the 2-ƒ JT-60SA ECHCD system.

  3. Assessment of QT and JT Intervals in Patients With Left Bundle Branch Block

    PubMed Central

    Tabatabaei, Peyman; Keikhavani, Ala; Haghjoo, Majid; Fazelifar, Amirfarjam; Emkanjoo, Zahra; Zeighami, Mahbobeh; Bakhshandeh, Hooman; Ghadrdoost, Behshid; Alizadeh, Abolfath

    2016-01-01

    Background Prolongation of the QT interval is considered a risk factor for cardiac adverse events and mortality. Left bundle branch block (LBBB) lengthens the QT interval. The corrected QT interval (QTc) is most likely overestimated because its prolongation is caused by increases in depolarization duration and not in repolarization. Objectives In this study, we aimed to apply corrected JT interval (JTc) as an appropriate measure of ventricular repolarization for predicting QTc in a formula. Patients and Methods The study population consisted of 101 patients with sinus rhythm (SR) and narrow QRS complexes (< 120 milliseconds). All patients underwent electrophysiology studies or ablation. A diagnostic catheter was positioned in the right ventricular apex (RVA) to induce LBBB at two different cycle lengths (CLs; 600 and 700 mv). The intrinsic QRS complex, QT time, and JT time were measured during SR and subsequent RVA pacing. The JTc was derived simply by subtracting the QRS duration from the QTc. Results Stimulation from the RVA increased the QTc from 456.20 ± 38.63 ms to 530.67 ± 47.73 ms at a CL of 600 (P < 0.0001) and to 502.32 ± 47.26 ms at 700 CL (P < 0.0001). JTc showed no significant changes with stimulation from the RVA (102.97 ± 11.35 ms vs. 103.59 ± 10.67 ms, P = 0.24). There was no significant correlation between JTc and QRS complex duration. A significant correlation was seen between QRS and QTc at both CLs. The ROC curve indicated that sensitivity of 80% and specificity of 67% were obtained with JTc duration of 92.6 ms. Conclusions Right ventricular pacing increases the QT interval without increasing the JT interval. Our results confirm that JTc, as an index of repolarization, is independent of ventricular depolarization. Therefore, it can be applied for predicting QTc in patients with LBBB. PMID:26949694

  4. Progress of high-power and long-pulse ECRF system development in JT-60

    NASA Astrophysics Data System (ADS)

    Kobayashi, T.; Isayama, A.; Yokokura, K.; Shimono, M.; Hasegawa, K.; Sawahata, M.; Suzuki, S.; Terakado, M.; Hiranai, S.; Sato, F.; Wada, K.; Hinata, J.; Sato, Y.; Ohzeki, M.; Takahashi, K.; Kajiwara, K.; Oda, Y.; Kasugai, A.; Sakamoto, K.; Hoshino, K.; Moriyama, S.

    2011-10-01

    A new gyrotron operation technique to increase oscillation efficiency was developed using the JT-60 electron cyclotron range of frequency (ECRF) system. In order to increase the efficiency without a significant increase in the anode leakage current by trapped electrons that limits the efficiency of gyrotrons with a collector potential depression technology, we actively optimized the electron pitch factor by controlling only the anode voltage within ~0.1 s after the start of the gyrotron operation, and a high-efficiency oscillation in the so-called hard-self-excitation region was achieved from the start of the oscillation. As an application of this technique in the JT-60 ECRF system, the gyrotron output power of 1.5 MW for 4 s, which is the longest pulse length in the world at an output power of 1.5 MW, was recorded with a successful reduction in the collector heat load by 20% as compared with the conventional operation. The reduced collector heat load at the 1.5 MW operation was acceptable for a steady-state operation. Further progress was made with respect to the expansion of the long-pulse capability of the ECRF system. A new gyrotron with an improved mode converter was developed in order to demonstrate a reduction in the stray radiation in the gyrotron; such radiation has thus far hindered long-pulse operations by causing an unacceptable heat load. We confirmed that the stray radiation was reduced to 1/3 of that of the original gyrotron; this reduced heat load is acceptable for steady-state operation. A conditioning operation of the improved gyrotron proceeds up to 31 s at 1 MW. This progress significantly contributes to an enhancement in the high-power and long-pulse capability of the ECRF system used in JT-60SA, where a total output power of 9 MW for 100 s is planned.

  5. JT9D engine diagnostics. Task 2: Feasibility study of measuring in-service flight loads. [747 aircraft performance

    NASA Technical Reports Server (NTRS)

    Kafka, P. G.; Skibo, M. A.; White, J. L.

    1977-01-01

    The feasibility of measuring JT9D propulsion system flight inertia loads on a 747 airplane is studied. Flight loads background is discussed including the current status of 747/JT9D loads knowledge. An instrumentation and test plan is formulated for an airline-owned in-service airplane and the Boeing-owned RA001 test airplane. Technical and cost comparisons are made between these two options. An overall technical feasibility evaluation is made and a cost summary presented. Conclusions and recommendations are presented in regard to using existing inertia loads data versus conducting a flight test to measure inertia loads.

  6. Edge pedestal characteristics in JET and JT-60U tokamaks under variable toroidal field ripple

    NASA Astrophysics Data System (ADS)

    Urano, H.; Saibene, G.; Oyama, N.; Parail, V.; de Vries, P.; Sartori, R.; Kamada, Y.; Kamiya, K.; Loarte, A.; Lönnroth, J.; Sakamoto, Y.; Salmi, A.; Shinohara, K.; Takenaga, H.; Yoshida, M.; JT-60 Team; EFDA Contributers, JET

    2011-11-01

    The effects of toroidal field (TF) ripple on the edge pedestal characteristics were examined in the TF ripple scan experiments at the plasma current Ip of 1.1 MA in JET and JT-60U. The TF ripple amplitude δR was defined as a value averaged over the existing ripple wells at the separatrix on the outer midplane. By the installation of ferritic inserts (FIs), δR was reduced from 1% to 0.6% at 3.2T (0.5% at 2.2 T) in JT-60U. In JET, δR was varied from 0.08% to 1% by feeding different currents to the odd and even set of coils out of 32 TF coils. The pedestal pressure pped was similar for the cases before and after the installation of FIs in JT-60U. Similarly, no clear difference in pped was also observed in the variation of δR in JET. The core and edge toroidal rotation clearly shifted in the counter-direction by increased δR. However, there were no changes in the spatial profiles of electron density, electron temperature and ion temperature. By the installation of FIs in JT-60U, the ELM frequency fELM decreased by ~20%, while the ELM energy loss increased by 50-150%. The increased ELM loss power by 30% suggests a reduction of inter-ELM transport with the reduced δR. In JET, fELM increased only slightly with increased δR while the edge toroidal rotation frequency decreased as δR increased. From the inter-machine similarity experiment at 1.1 MA, TF ripple less than 1% does not strongly affect the pedestal pressure. However, in the single TF ripple scan at the higher Ip of 2.6 MA in JET, it clearly decreases with the increased δR, accompanying with a strong density pump out at large TF ripple. These results suggests that the effect of TF ripple on H-mode properties becomes stronger in the plasmas with higher Ip or lower edge collisionality of ripple diffusion.

  7. Optical modeling and physical performances evaluations for the JT-60SA ECRF antenna

    NASA Astrophysics Data System (ADS)

    Platania, P.; Figini, L.; Farina, D.; Isayama, A.; Kobayashi, T.; Micheletti, D.; Moriyama, S.; Moro, A.; Sozzi, C.

    2015-12-01

    The purpose of this work is the optical modeling and physical performances evaluations of the JT-60SA ECRF launcher system. The beams have been simulated with the electromagnetic code GRASP® and used as input for ECCD calculations performed with the beam tracing code GRAY, capable of modeling propagation, absorption and current drive of an EC Gaussion beam with general astigmatism. Full details of the optical analysis has been taken into account to model the launched beams. Inductive and advanced reference scenarios has been analysed for physical evaluations in the full poloidal and toroidal steering ranges for two slightly different layouts of the launcher system.

  8. Design of collection optics and polychromators for a JT-60SA Thomson scattering system

    SciTech Connect

    Tojo, H.; Hatae, T.; Sakuma, T.; Hamano, T.; Itami, K.; Aida, Y.; Suitoh, S.; Fujie, D.

    2010-10-15

    This paper presents designs of collection optics for a JT-60SA Thomson scattering system. By using tangential (to the toroidal direction) YAG laser injection, three collection optics without strong chromatic aberration generated by the wide viewing angle and small design volume were found to measure almost all the radial space. For edge plasma measurements, the authors optimized the channel number and wavelength ranges of band-pass filters in a polychromator to reduce the relative error in T{sub e} by considering all spatial channels and a double-pass laser system with different geometric parameters.

  9. High Beta Steady State Research and Future Directions on JT-60U and JFT-2M

    NASA Astrophysics Data System (ADS)

    Ishida, Shinichi

    2003-10-01

    JT-60U and JFT-2M research is focused on high beta steady state operation towards economically and environmentally attractive reactors. In JT-60U, a high-βp H-mode plasma was sustained with βN 2.7 for 7.4 s in which neoclassical tearing modes (NTMs) limited the attainable β_N. Real-time tracking NTM stabilization system using ECCD demonstrated complete suppression of NTM leading to recovery of βN before onset of NTM. Performance in a fully non-inductive H-mode plasma was improved up to n_i(0) τE T_i(0) = 3.1 x 10^20 keV s m-3 using N-NBCD with βN 2.4, HH_y,2=1.2 and bootstrap fraction f_BS 0.5. ECH experiments extended the confinement enhancement for dominantly electron heated reversed shear plasmas up to HH_y,2 2 at T_e/Ti 1.25. A world record ECCD efficiency, 4.2 x 10^18 A/W/m^2, was achieved at Te 23 keV with a highly localized central current density. Innovative initiation and current build-up without center solenoid currents were established by LHCD/ECH and bootstrap current up to f_BS 0.9. In JFT-2M, the inside of the vacuum vessel wall was fully covered with low-activation ferritic steel plates to investigate their use in plasmas near fusion conditions. High βN plasmas were produced up to βN = 3.3 with an internal transport barrier (ITB) and a steady H-mode edge. A new H-mode regime with steady high recycling (HRS) and an ITB was exploited leading to βN H_89P 6.2 at n_e/nG 0.7. In 2003, JT-60U will be able to operate for the duration up to 65 s at 1 MA/2.7 T and the heating/current-drive duration up to 30 s at 17 MW to prolong high-βN and/or high-f_BS discharges with feedback controls. JFT-2M is planning to implement wall stabilization experiments in 2004 to pursue plasmas above the ideal no-wall limit using a ferritic wall. The modification of JT-60 to a fully superconducting tokamak is under discussion to explore high-β steady state operation in collision-less plasmas well above no-wall limit with ferritic wall in a steady state.

  10. JT8D-15/17 High Pressure Turbine Root Discharged Blade Performance Improvement. [engine design

    NASA Technical Reports Server (NTRS)

    Janus, A. S.

    1981-01-01

    The JT8D high pressure turbine blade and seal were modified, using a more efficient blade cooling system, improved airfoil aerodynamics, more effective control of secondary flows, and improved blade tip sealing. Engine testing was conducted to determine the effect of these improvements on performance. The modified turbine package demonstrated significant thrust specific fuel consumption and exhaust gas temperature improvements in sea level and altitude engine tests. Inspection of the improved blade and seal hardware after testing revealed no unusual wear or degradation.

  11. High reflection LH experiments with the JT-60U launcher with oversized waveguides

    SciTech Connect

    Tuccillo, A.A.; Podda, S.; Seki, M.; Asakura, N.; Ide, S.; Ikeda, Y.; Kimura, H.; Kondoh, T.; Naito, O.; Ushigusa, K.; JT-60U Team

    1996-02-01

    The Current Drive performances of the JT-60U multijunction launcher, fed by oversized waveguides, have been investigated under poor matching conditions. In the experiments the main waveguides reflection coefficient reached values of 35{percent}, moving the grill in the shadow of the port. Good agreement is found between measured and expected reflection coefficient computed without taking into account the generation of higher modes in the oversized guides and using a model for the density in front of the grill deduced from Langmuir probe measurements. Good current drive performances are observed up to reflection coefficients as high as 25{percent}, well above the theoretical expectation. {copyright} {ital 1996 American Institute of Physics.}

  12. Characteristics of a large multijunction launcher for high-power LHCD experiments on JT-60U

    SciTech Connect

    Seki, M.; Ikeda, Y.; Ushigusa, K.; Naito, O.; Kondoh, T.; Wolfe, S.W.; Imai, T. )

    1994-10-15

    This paper presents overview of a large multijunction launcher for JT-60U. The launcher is featured by the multijunction module with the oversized taper waveguide, in order to simplify structure of the launcher. This launcher allows high performances of current drive and current profile control by using very sharp and highly directive spectrum. Initial result of coupling property is also described. A good coupling was observed at a power level of [similar to]0.8 MW with plasma-launcher distance of [lt]14 cm.

  13. Edge safety factor at the onset of plasma disruption during VDEs in JT-60U

    NASA Astrophysics Data System (ADS)

    Sugihara, Masayoshi; Lukash, Victor; Khayrutdinov, Rustam; Neyatani, Yuzuru

    2004-10-01

    Detailed examinations of the value of the edge safety factor (qa) at the onset of thermal quench (TQ) during intentional vertical displacement event (VDE) experiments in JT-60U are carried out using two different reconstruction methods, FBI/FBEQU and DINA. The results from the two methods are very similar and show that the TQ occurs when the qa value is in the range between 1.5 and 2. This result suggests that the predictive simulations for VDEs should be performed within this range of q to examine the subsequent differences in the halo currents, plasma movement and other plasma behaviour during the current quench.

  14. Aerodynamic performance of 0.4066-scale model to JT8D refan stage

    NASA Technical Reports Server (NTRS)

    Moore, R. D.; Kovich, G.; Tysl, E. R.

    1976-01-01

    The aerodynamic performance of a scale model of the split flow JT8D rafan stage is presented over a range of flows at speeds from 40 to 100 percent design. The bypass stage peak efficiency of 0.800 occurred at a total weight flow of 35.82 kilograms per second and a pressure ratio of 1.697. The stall margin was 15 percent based on pressure ratio and weight flow at stall and peak efficiency conditions. The data indicated that the hub region of the core stators was choked at design speed over the entire flow range tested.

  15. JT-60U Plasma Current Measurement by an Optical Current Transformer

    SciTech Connect

    Arai, Takashi; Nishiyama, Tomokazu; Yagyu, Junichi; Kasai, Satoshi; Sone, Isamu; Abe, Mitsushi; Miya, Naoyuki

    2004-01-15

    In a nuclear fusion experiment device, a plasma discharge is to be sustained for a long time in steady state operation. In such a device an electromagnetic sensor that has a signal integrator to measure direct currents will cause a technical problem of zero point drift on signals. Therefore, the detection device using new technology for direct current measurement, optical current transformer (optical CT), was developed. The device has an optical fiber specified for 850 and 1550nm (wavelength) were manufactured, and was applied to current measurement in JT-60U experiments. A gamma ray irradiation examination was also done to the optical CT.

  16. JT9D performance deterioration results from a simulated aerodynamic load test

    NASA Technical Reports Server (NTRS)

    Stakolich, E. G.; Stromberg, W. J.

    1981-01-01

    The results of testing to identify the effects of simulated aerodynamic flight loads on JT9D engine performance are presented. The test results were also used to refine previous analytical studies on the impact of aerodynamic flight loads on performance losses. To accomplish these objectives, a JT9D-7AH engine was assembled with average production clearances and new seals as well as extensive instrumentation to monitor engine performance, case temperatures, and blade tip clearance changes. A special loading device was designed and constructed to permit application of known moments and shear forces to the engine by the use of cables placed around the flight inlet. The test was conducted in the Pratt & Whitney Aircraft X-Ray Test Facility to permit the use of X-ray techniques in conjunction with laser blade tip proximity probes to monitor important engine clearance changes. Upon completion of the test program, the test engine was disassembled, and the condition of gas path parts and final clearances were documented. The test results indicate that the engine lost 1.1 percent in thrust specific fuel consumption (TSFC), as measured under sea level static conditions, due to increased operating clearances caused by simulated flight loads. This compares with 0.9 percent predicted by the analytical model and previous study efforts.

  17. Applying the CO2 laser collective Thomson scattering results from JT-60U to other machines

    NASA Astrophysics Data System (ADS)

    Richards, R. K.; Hutchinson, D. P.; Bennett, C. A.; Kondoh, T.; Miura, Y.; Lee, S.

    2003-03-01

    A collective Thomson scattering (CTS) system based on a pulsed CO2 laser is being developed to demonstrate the feasibility of alpha-particle diagnostics. Tests on this system are being conducted on the JT-60U tokamak. The system consists of a pulsed laser (15 J in 1:s at 10.6:m) and a wide band (˜8 GHz) heterodyne receiver with a quantum-well infrared photodetector [Liu et al., IEEE Electron Device Lett. 16, 253 (1995)]. Stray light is reduced by a notch filter containing hot CO2 gas. The heterodyne receiver is absolutely calibrated using a large area blackbody radiation source [Bennett et al., Appl. Opt. 27, 3324 (1988)]. Results from the tests on JT-60U indicate a larger than expected noise background, especially for the lower velocity measurements determined by the smaller frequency shifts from the laser line. These results are used to estimate the signal-to-noise ratio that would be expected for a CTS diagnostic installed on other devices; ITER ("the way" in Latin), Joint European Torus-Enhanced Performance JET-EP, and axially symmetric divertor experiment (ASDEX). Calculations and possible system improvements are presented.

  18. DC-9 Flight Demonstration Program with Refanned JT8D Engines. Volume 3; Performance and Analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The JT8D-109 engine has a sea level static, standard day bare engine takeoff thrust of 73,840 N. At sea level standard day conditions the additional thrust of the JT8D-109 results in 2,040 kg additional takeoff gross weight capability for a given field length. Range loss of the DC-9 Refan airplane for long range cruise was determined. The Refan airplane demonstrated stall, static longitudinal stability, longitudinal control, longitudinal trim, minimum control speeds, and directional control characteristics similar to the DC-9-30 production airplane and complied with airworthiness requirements. Cruise, climb, and thrust reverser performance were evaluated. Structural and dynamic ground test, flight test and analytical results substantiate Refan Program requirements that the nacelle, thrust reverser hardware, and the airplane structural modifications are flightworthy and certifiable and that the airplane meets flutter speed margins. Estimated unit cost of a DC-9 Refan retrofit program is 1.338 million in mid-1975 dollars with about an equal split in cost between airframe and engine.

  19. DC-9 flight demonstration program with refanned JT8D engines. Volume 4: Flyover noise

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Flyover noise tests were conducted to determine the noise reductions achievable by modifying the engines and nacelles of DC-9-30 airplanes. The two stage fan of the JT8D-9 engine was replaced with a larger diameter, single stage fan and sound absorbing materials were incorporated in the engines and nacelles. The noise levels were determined to be 95.3 EPNdB at the sideline, 96.2 EPNdB for a full thrust takeoff, 87.5 EPNdB for takeoff with thrust cutback, and 97.4 EPNdB for landing approach. The noise reductions relative to the hardwall JT8D-9 were 8.2 EPNdB for takeoff with cutback and 8.7 EPNdB for landing. The 90 EPNdB noise contour areas were reduced by 40% for missions requiring maximum design takeoff and landing weights. For typical mission weights, the reductions were 19% for full thrust takeoff and 34% for takeoff with cutback. The 95 EPNdB contour areas were reduced by 50% for takeoff and 30% for takeoff with cutback for both missions.

  20. JT90 Ceramic Outer Air Seal System Refinement Program, Phase 2

    NASA Technical Reports Server (NTRS)

    Shiembob, L. T.

    1982-01-01

    The sprayed ceramic gas turbine outer air seal system was tested in two JT9D engines to substantiate the abradability and durability of the seals. Of particular significance was that one of the tests, a 150 hour 1000 cycle endurance program at nominal JT9D operating conditions, was completed with minimal effect on the seals and received Federal Aviation Administration cognizance with respect to potential field service use by the airlines. The other engine test completed 1825 endurance cycles at severe operating conditions and no burn through or other serious defects in the structural integrity of a seal segment was observed. These test results combined with other Pratt and Whitney Aircraft engine tests substantiate the potential of the ceramic outer air seal system to attain the durability goal of 50000 hour engine operating capability. Both engine tests subjected the seals to intentional blade rubs and demonstrated good abradability with volume wear ratios greater than 100, far exceeding the design goal of 10. The improved volume wear ratio will allow the turbine tip clearance to be reduced, thereby resulting in an estimated thrust specific fuel consumption improvement of 0.3 percent.

  1. Development of computer-aided software engineering tool for sequential control of JT-60U

    SciTech Connect

    Shimono, M.; Akasaka, H.; Kurihara, K.; Kimura, T.

    1995-12-31

    Discharge sequential control (DSC) is an essential control function for the intermittent and pulse discharge operation of a tokamak device, so that many subsystems may work with each other in correct order and/or synchronously. In the development of the DSC program, block diagrams of logical operation for sequential control are illustrated in its design at first. Then, the logical operators and I/O`s which are involved in the block diagrams are compiled and converted to a certain particular form. Since the block diagrams of the sequential control amounts to about 50 sheets in the case of the JT-60 upgrade tokamak (JT-60U) high power discharge and the above steps of the development have been performed manually so far, a great effort has been required for the program development. In order to remove inefficiency in such development processes, a computer-aided software engineering (CASE) tool has been developed on a UNIX workstation. This paper reports how the authors design it for the development of the sequential control programs. The tool is composed of the following three tools: (1) Automatic drawing tool, (2) Editing tool, and (3) Trace tool. This CASE tool, an object-oriented programming tool having graphical formalism, can powerfully accelerate the cycle for the development of the sequential control function commonly associated with pulse discharge in a tokamak fusion device.

  2. Development of High Power Gyrotron and Power Modulation Technique using the JT-60U ECRF System

    NASA Astrophysics Data System (ADS)

    Kobayashi, Takayuki; Terakado, Masayuki; Sato, Fumiaki; Yokokura, Kenji; Shimono, Mitsugu; Hasegawa, Koichi; Sawahata, Masayuki; Suzuki, Sadaaki; Hiranai, Shinichi; Igarashi, Koichi; Wada, Kenji; Suzuki, Takashi; Kajiwara, Ken; Kasugai, Atsushi; Sakamoto, Keishi; Isayama, Akihiko; Matsunaga, Go; Moriyama, Shinichi

    Electron cyclotron range of frequency system of the JT-60U finished operation at the end of August 2008, and improvements toward JT-60SA have been started. In the last two years stable gyrotron oscillation at an output power of 1.5 MW for 1 s was demonstrated, for the first time, using the 110 GHz gyrotron. It was verified that the heat load on the cavity was at an acceptable level with continuous oscillations at 1.5 MW. The absorption power of the collector was also at an acceptable level for the longer pulse oscillation of 5 s. A power modulation technique based on anode voltage modulation was also developed in order to study the effects of modulated Electron Cyclotron Current Drive (ECCD) on Neoclassical Tearing Mode (NTM) stabilization. Modulation frequencies of up to 7 kHz were achieved at output power of 0.8 MW exceeding the previous limit of 3 kHz. Modulated ECCD experiments in synchronization with the NTM were successfully performed with a modulation frequency of around 5 kHz. Development of an accurate synchronization system played an essential role in the experiments that needed a maintained phase between the magnetic probe signal and modulated ECCD in real time. The results provide significant information for further developments that will enhance the overall performance of ECRF systems in the near future.

  3. JT9D performance deterioration results from a simulated aerodynamic load test

    NASA Technical Reports Server (NTRS)

    Stakolich, E. G.; Stromberg, W. J.

    1981-01-01

    This paper presents the results of testing to identify the effects of simulated aerodynamic flight loads on JT9D engine performance. The test results were also used to refine previous analytical studies on the impact of aerodynamic flight loads on performance losses. To accomplish these objectives, a JT9D-7AH engine was assembled with average production clearances and new seals as well as extensive instrumentation to monitor engine performance, case temperatures, and blade tip clearance changes. A special loading device was designed and constructed to permit application of known moments and shear forces to the engine by the use of cables placed around the flight inlet. The test was conducted in the Pratt and Whitney Aircraft X-Ray Test Facility to permit the use of X-ray techniques in conjunction with laser blade tip proximity probes to monitor important engine clearance changes. Upon completion of the test program, the test engine was disassembled, and the condition of gas path parts and final clearances were documented. The test results indicate that the engine lost 1.1 percent in thrust specific fuel consumption (TSFC), as measured under sea level static conditions, due to increased operating clearances caused by simulated flight loads. This compares with 0.9 percent predicted by the analytical model and previous study efforts.

  4. 76 FR 77107 - Airworthiness Directives; Pratt & Whitney Corp. (PW) JT9D-7R4H1 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for all PW JT9D-7R4H1 turbofan engines. This AD was prompted by... information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA...

  5. Overview of JT-60U results towards the resolution of key physics and engineering issues in ITER and JT-60SA

    NASA Astrophysics Data System (ADS)

    Isayama, A.; JT-60 Team

    2011-09-01

    This paper presents an overview of recent results from JT-60U. Topics we particularly focus on are (1) the mechanism determining the rotation profile and the effect of rotation on/from transport and stability, (2) the edge localized mode (ELM) physics and active ELM control and (3) plasma-wall interactions. An analysis of the momentum transport showed that rotation with a high pressure gradient can be reproduced by introducing a residual stress term proportional to the momentum diffusivity and the pressure gradient. Also, the momentum diffusivity in an internal transport barrier (ITB) region was reduced to an order similar to that of the ion thermal diffusivity. A comparison of the edge pedestal characteristics between JT-60U and JET with matched shape and operational parameters showed that the edge pressure did not change with increasing toroidal field (TF) ripple up to 1%, whereas a linear shift of the rotation velocity to the counter-direction was observed with increasing TF ripple. The absolute evaluation of tungsten accumulation in the core plasma by a spectroscopic method clarified that tungsten accumulation increased with increasing toroidal rotation in the counter-direction while an H-mode was sustained even at a tungsten density of 10-3 times the electron density. Active control of neoclassical tearing mode (NTM) islands by the electron cyclotron current drive showed that the growth of NTM islands decelerated the plasma rotation. A transition to a low-rotation frequency state occurred for larger NTM islands. A statistical analysis of the precursor of type I ELM showed a small growth rate of γ/ωA ~ 10-3 (where γ and ωA are the growth rate and Alfvén angular frequency, respectively). The measurement of the precursor at different toroidal locations showed that the toroidal mode number was 8-10 or 14-16. Energetic-particle-driven wall modes (EWMs) were found to trigger ELMs and decrease the ELM amplitude to half of that without EWMs. Enhancement of the ELM frequency by electron cyclotron heating in the edge region of the high-field side was observed, and the frequency increase was four times than that of neutral beam injection cases having the same absorption power. Laser scattering measurement of carbon dust generation showed that the dust distribution had a peak in the far scrape-off layer and penetration into the core plasma was not significant. Depth profile measurements of deuterium and carbon in tungsten-coated tiles (tungsten thickness: 50 µm) determined that the ratio of deuterium to carbon was 0.06 ± 0.02 over a 20 µm depth, suggesting deuterium trapping by carbon in the tungsten layer. Furthermore, new records for both the beam energy of negative-ion-based neutral beams (507 keV) and the output power of 110 GHz electron cyclotron waves (1.5 MW for 4 s from one gyrotron) were achieved, which confirmed and extended the heating and current drive capabilities of ITER and JT-60SA.

  6. Fast neutron-gamma discrimination on neutron emission profile measurement on JT-60U

    SciTech Connect

    Ishii, K.; Okamoto, A.; Kitajima, S.; Sasao, M.; Shinohara, K.; Ishikawa, M.; Baba, M.; Isobe, M.

    2010-10-15

    A digital signal processing (DSP) system is applied to stilbene scintillation detectors of the multichannel neutron emission profile monitor in JT-60U. Automatic analysis of the neutron-{gamma} pulse shape discrimination is a key issue to diminish the processing time in the DSP system, and it has been applied using the two-dimensional (2D) map. Linear discriminant function is used to determine the dividing line between neutron events and {gamma}-ray events on a 2D map. In order to verify the validity of the dividing line determination, the pulse shape discrimination quality is evaluated. As a result, the {gamma}-ray contamination in most of the beam heating phase was negligible compared with the statistical error with 10 ms time resolution.

  7. Simulation Study on the ITB Formation during LHCD in JT-60U

    NASA Astrophysics Data System (ADS)

    Cui, Zheng-ying; Osamu, Naito; Takeshi, Fukudai; Hiroshi, Shirai; Yoshitaka, Ikeda; Kenkichi, Ushigusa

    2002-04-01

    A transport simulation has been done by using a 1.5D time dependent transport code to reproduce a formation of the ITB on electron temperature profile during the long pulse LHCD in JT-60U tokamak. The transport coefficients were assumed to reduce with a reversed magnetic shear and the LH driven current profile was evaluated by fitting dynamic change in the measured current profile. The gradual increase in the central electron temperature could be explained by the change in the current profile during LHCD in the present simulation model. The estimated LH-driven current profile by the transport code analysis shows a finite current density at the plasma center. Analysis of transport simulation suggests some mechanisms for broadening the LH-driven current profile at the central region of the plasma.

  8. Dependence of pedestal structure on collisionality at fixed beta in JT-60U

    NASA Astrophysics Data System (ADS)

    Urano, H.; Aiba, N.; Kamiya, K.; Kamada, Y.; the JT-60 Team

    2016-01-01

    The dependence of pedestal structure on collisionality at fixed beta has been investigated in JT-60U. In the ITER-relevant low collisionality regime, the pedestal width does not change with edge collisionality. In the high collisionality regime, the pedestal width broadens with increased edge collisionality. The pedestal pressure gradient and width are not significantly changed when the pedestal is close to an intermediate n peeling-ballooning mode boundary at low collisionality. The experimental result indicates that conventional pedestal models where the pedestal width is independent of collisionality and is determined by {β\\text{p}} at the pedestal is not a bad assumption in the ITER-relevant low collisionality regime. On the other hand, the pressure gradient decreases and the pedestal width increases at high collisionality. The pedestal broadening becomes significant when the pedestal is marginal to be unstable at the high n ballooning mode in the high collisionality regime.

  9. Numerical analyses of JT-60SA scenarios with the COREDIV code

    NASA Astrophysics Data System (ADS)

    Zagórski, R.; Giruzzi, G.; Gałazcedilka, K.; Ivanova-Stanik, I.; Romanelli, M.; Stȩpniewski, W.

    2016-01-01

    JT-60SA design scenarios have been analyzed with the help of the self-consistent core-edge COREDIV code, with the aim to assess the influence of impurities on the plasma parameters and tokamak performance. In particular, the reduction of divertor target power load due to radiation of sputtered and externally seeded impurities has been investigated. For all scenarios considered, the gradual replacement of carbon by low Z seeding impurity (N, Ne) is observed as the gas influx increases. For high auxiliary power and low density scenarios, the carbon and seeding impurity radiation does not effectively reduce power to plate. Consequently, results with very high {{Z}\\text{eff}} (about 6-8) and impurity concentrations (>9%) are observed. For these scenarios, seeding of the high Z impurity like krypton seems to be more appropriate, in particular when the plasma density is increased.

  10. Development of a Real-time Modulation Control System on the JT-60U ECRF System

    SciTech Connect

    Kobayashi, T.; Isayama, A.; Terakado, M.; Sato, F.; Suzuki, S.; Hiranai, S.; Shibayama, M.; Moriyama, S.

    2009-11-26

    A real-time modulation control system was developed for studying the effectiveness of modulated Electron Cyclotron Current Drive (ECCD) on the stabilization of Neoclassical Tearing Modes (NTMs). The phase and duty cycle tracking was enabled with high accuracy even if the NTM frequency varied during ECCD. A characteristic of an anode voltage modulation for modulating the gyrotron oscillation that caused the time variation of the phase and duty cycle was also taking into account. It was shown that the phase and duty cycle could be kept the target values within 50 ms even if the frequency varied by 1 kHz/s or higher at a frequency of around 5 kHz. Then, NTM stabilization experiments with modulated ECCD for m/n = 2/1 NTM was successfully performed in JT-60U.

  11. JT8D revised high-pressure turbine cooling and other outer air seal program

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1979-01-01

    The JT8D high pressure turbine was revised to reduce leakage between the blade tip shrouds and the outer air seal, and engine testing was performed to determine the effect on performance. The addition of a second knife-edge on the blade tip shroud, the extension of the honeycomb seal land to cover the added knife-edge and an existing spoiler on the shroud, and a material substitution in the seal support ring to improve thermal growth characteristics are included. A relocation of the blade cooling air discharge to insure adequate cooling flow is required. Significant specific fuel consumption and exhaust gas temperature improvements were demonstrated with the revised turbine in sea level and simulated altitude engine tests. Inspection of the revised seal hardware after these tests showed no unusual wear or degradation.

  12. Launcher heat load on high power LHCD experiments in JT-60U

    NASA Astrophysics Data System (ADS)

    Naito, O.; Ikeda, Y.; Seki, M.; Ide, S.; Kondoh, T.; Ushigusa, K.

    1995-04-01

    Heat loads on a lower hybrid wave launcher as well as on the first wall during high power auxiliary heating and their origin are investigated. It is found that the heat load on the launcher is moderate during injection of lower hybrid wave into a ohmic plasma. However, it is significantly enhanced by the existence of high energy banana-trapped particles and localized near the equatorial plane. In JT-60U, lower hybrid wave can be coupled to the plasma at a launcher-plasma distance of ˜ 20 cm without any significant heat load on the launcher grill. Nevertheless, the heat load due to banana-orbit particles may impose a constraint on the position of a launcher.

  13. Behaviour of light impurities in beam-heated jt-60 plasmas with hot graphite walls

    NASA Astrophysics Data System (ADS)

    JT-60 Team; Nishino, N.; Kubo, H.; Sakasai, A.; Koide, Y.; Sugie, T.; Takeuchi, T.

    1989-04-01

    The behaviour of light impurities in beam-heated JT-60 plasmas, after changing the limiter and armour tile material from TiC coated molybdenum and inconel to graphite, is discussed. In limiter discharges with high power neutral injection of greater than 12 MW and small gas puff rate, it is generally observed that the influx of carbon increases during the neutral beam phase. This phenomenon is delayed when the base temperature of the vacuum vessel is low. If the heat load to the wall is taken to be 6 MW/m 2 then it is estimated that the increased carbon influx occurs at a wall temperature of 800 K. This temperature coincides with that for maximum chemical sputtering. The strongly rising influx of carbon is therefore attributed to chemical sputtering.

  14. The 727 airplane target thrust reverser static performance model test for refanned JT8D engines

    NASA Technical Reports Server (NTRS)

    Chow, C. T. P.; Atkey, E. N.

    1974-01-01

    The results of a scale model static performance test of target thrust reverser configurations for the Pratt and Whitney Aircraft JT8D-100 series engine are presented. The objective of the test was to select a series of suitable candidate reverser configurations for the subsequent airplane model wind tunnel ingestion and flight controls tests. Test results indicate that adequate reverse thrust performance with compatible engine airflow match is achievable for the selected configurations. Tapering of the lips results in loss of performance and only minimal flow directivity. Door pressure surveys were conducted on a selected number of lip and fence configurations to obtain data to support the design of the thrust reverser system.

  15. Simulation of plasma current ramp-up with reduced magnetic flux consumption in JT-60SA

    NASA Astrophysics Data System (ADS)

    Wakatsuki, T.; Suzuki, T.; Hayashi, N.; Shiraishi, J.; Ide, S.; Takase, Y.

    2015-06-01

    Current ramp-up with reduced central solenoid (CS) flux consumption in JT-60SA has been investigated using an integrated modeling code suite (TOPICS) with a turbulent model (CDBM). The plasma current can be ramped-up from 0.6 MA to 2.1 MA with no additional CS flux consumption if the plasma current is overdriven by neutral-beam-driven and bootstrap current. A time duration required for the current ramp-up without CS flux consumption becomes as long as 150 s in the scenario we have examined. In order to achieve a current overdrive condition from 0.6 MA, the current drive by a lower energy neutral beam (85 keV) is effective. A higher energy neutral beam (500 keV) cannot be used in this early phase with a low central electron density (~2 × 1019 m-3) due to large shine through loss, while it can be effectively used in the later phase. Therefore, the main current driver should be switched from the lower energy neutral beam to the higher energy neutral beam during the current ramp-up phase. As a result of an intensive auxiliary heating, plasma beta (the ratio of the plasma pressure to the magnetic pressure) becomes high. Ideal MHD instabilities of such high beta plasmas have been investigated using a linear ideal MHD stability analysis code (MARG2D). External kink modes which might affect the core plasma can be stabilized during the current ramp-up if there is a perfectly conducting wall at the location of the stabilizing plate and the vacuum vessel of JT-60SA and the plasma has a broader pressure profile with the H-mode pedestal and the internal transport barrier.

  16. Development of the negative ion beams relevant to ITER and JT-60SA at Japan Atomic Energy Agency

    NASA Astrophysics Data System (ADS)

    Hanada, M.; Kojima, A.; Tobari, H.; Nishikiori, R.; Hiratsuka, J.; Kashiwagi, M.; Umeda, N.; Yoshida, M.; Ichikawa, M.; Watanabe, K.; Yamano, Y.; Grisham, L. R.

    2016-02-01

    In order to realize negative ion sources and accelerators to be applicable to International Thermonuclear Experimental Reactor and JT-60 Super Advanced, a large cesium (Cs)-seeded negative ion source and a multi-aperture and multi-stage electric acceleration have been developed at Japan Atomic Energy Agency (JAEA). Long pulse production and acceleration of the negative ion beams have been independently carried out. The long pulse production of the high current beams has achieved 100 s at the beam current of 15 A by modifying the JT-60 negative ion source. The pulse duration time is increased three times longer than that before the modification. As for the acceleration, a pulse duration time has been also extended two orders of magnitudes from 0.4 s to 60 s. The developments of the negative ion source and acceleration at JAEA are well in progress towards the realization of the negative ion sources and accelerators for fusion applications.

  17. Development of the negative ion beams relevant to ITER and JT-60SA at Japan Atomic Energy Agency.

    PubMed

    Hanada, M; Kojima, A; Tobari, H; Nishikiori, R; Hiratsuka, J; Kashiwagi, M; Umeda, N; Yoshida, M; Ichikawa, M; Watanabe, K; Yamano, Y; Grisham, L R

    2016-02-01

    In order to realize negative ion sources and accelerators to be applicable to International Thermonuclear Experimental Reactor and JT-60 Super Advanced, a large cesium (Cs)-seeded negative ion source and a multi-aperture and multi-stage electric acceleration have been developed at Japan Atomic Energy Agency (JAEA). Long pulse production and acceleration of the negative ion beams have been independently carried out. The long pulse production of the high current beams has achieved 100 s at the beam current of 15 A by modifying the JT-60 negative ion source. The pulse duration time is increased three times longer than that before the modification. As for the acceleration, a pulse duration time has been also extended two orders of magnitudes from 0.4 s to 60 s. The developments of the negative ion source and acceleration at JAEA are well in progress towards the realization of the negative ion sources and accelerators for fusion applications. PMID:26932050

  18. Finite element-integral simulation of static and flight fan noise radiation from the JT15D turbofan engine

    NASA Technical Reports Server (NTRS)

    Baumeister, K. J.; Horowitz, S. J.

    1982-01-01

    An iterative finite element integral technique is used to predict the sound field radiated from the JT15D turbofan inlet. The sound field is divided into two regions: the sound field within and near the inlet which is computed using the finite element method and the radiation field beyond the inlet which is calculated using an integral solution technique. The velocity potential formulation of the acoustic wave equation was employed in the program. For some single mode JT15D data, the theory and experiment are in good agreement for the far field radiation pattern as well as suppressor attenuation. Also, the computer program is used to simulate flight effects that cannot be performed on a ground static test stand.

  19. 76 FR 41144 - Airworthiness Directives; Pratt & Whitney Corp. (PW) JT9D-7R4H1 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ...We propose to adopt a new airworthiness directive (AD) for all PW JT9D-7R4H1 turbofan engines. This proposed AD would require removing certain high-pressure compressor (HPC) shafts before their certified life limits, and establishes a new, lower life-limit for these parts. This proposed AD was prompted by reports of cracks in five HPC shafts. We are proposing this AD to correct the unsafe......

  20. Development of Fast Measurement System of Neutron Emission Profile Using a Digital Signal Processing Technique in JT-60U

    SciTech Connect

    Ishikawa, M.; Shinohara, K.; Itoga, T.; Okuji, T.; Nakhostin, M.; Baba, M.; Nishitani, T.

    2008-03-12

    Neutron emission profiles are routinely measured in JT-60U Tokamak. Stinbene neuron detectors (SNDs), which combine a Stilbene organic crystal scintillation detector (Stilbene detector) with an analog neutron-gamma pulse shape discrimination (PSD) circuit, have been used to measure neutron flux efficiently. Although the SND has many advantages as a neutron detector, the maximum count rate is limited up to {approx}1x 10{sup 5} counts/s due to the dead time of the analog PSD circuit. To overcome this issue, a digital signal processing (DSP) system using a Flash-ADC has been developed. In this system, anode signals from the photomultiplier of the Stilbene detector are fed to the Flash ADC and digitized. Then, the PSD between neutrons and gamma-rays are performed using software. The photomultiplier tube is also modified to suppress and correct gain fluctuation of the photomultiplier. The DSP system has been installed in the center channel of the vertical neutron collimator system in JT-60U and applied to measurements of neutron flux in JT-60U experiments. Neutron flux are successfully measured with count rate up to {approx}1x 10{sup 6} counts/s without the effect of pile up of detected pulses. The performance of the DSP system as a neutron detector is demonstrated.

  1. A 727 airplane center duct inlet low speed performance confirmation model test for refanned JT8D engines, phase 2

    NASA Technical Reports Server (NTRS)

    Kaldschmidt, G.; Syltebo, B. E.; Ting, C. T.

    1973-01-01

    The results from testing of a 0.3 scale model center duct inlet (S duct) for the Pratt and Whitney Aircraft JT8D-100 engines are presented. The objective of this test was to demonstrate that the required airflow of the JT8D-100 engine (480 lb/sec as compared to 334 lb/sec for JT8D-15) can be achieved with minimum modifications to the existing 727 airplane structure at acceptable levels of total pressure recovery and distortion. Steady-state pressure recovery, steady-state pressure distortion, and dynamic pressure measurements were taken at the engine face station. Surface static pressure measurements were taken along the duct. Test results indicated that the required airflow was achieved with acceptable pressure recovery (comparable to the current 727-200 S duct). Inlet inflow angle variation within the 727 airplane operating regime (minus 5 to 5 degrees) had no effect on the inlet performance. Pressure distortion at static and forward speed at takeoff airflow conditions are within P and WA limits for the Phase II duct when equipped with vortex generators. Static crosswind operation between 10 knots and 25 knots appears feasible at full takeoff power.

  2. Overview of JT-60U progress towards steady-state advanced tokamak

    NASA Astrophysics Data System (ADS)

    Ide, S.; JT-60 Team

    2005-10-01

    Recent experimental results from steady-state advanced tokamak (AT) research on JT-60U are presented with emphasis on time scales longer in comparison with the characteristic time scales in plasmas. To achieve this, modification of the controls for the operation, heating and diagnostics systems have been carried out. As a result, ~60 s current flat top and a ~30 s H-mode are obtained. The long pulse modification has opened a door into a new domain for JT-60U. High normalized beta (βN) of 2.3 is maintained for 22.3 s and 2.5 for 16.5 s in a high-βp H-mode plasma. A standard ELMy H-mode plasma has also been extended and changes in the wall recycling on the longer time scale have been unveiled. The development and investigation of plasmas relevant to AT operation have been continued in long discharges as well as in discharges where higher NB power is available (<=10 s). Higher βN (~3) is maintained for 6.2 s in a high-βp H-mode plasma. High bootstrap current fraction (fBS) of ~75% is sustained for 7.4 s in a reversed shear plasma. Neo-classical tearing mode (NTM) suppression by localized ECCD is found to be more effective with ECRF injection preceding the mode saturation. The mode is suppressed with less power compared to the injection after the mode saturates. The domain of the NTM suppression experiments is extended to the high-βN regime, and the effectiveness of m/n = 3/2 mode suppression by ECCD is demonstrated at βN ~ 2.5-3. Genuine tokamak plasma start up without a central solenoid is demonstrated. In a current hole region, it is shown that no scheme drives current in any direction. Detailed measurement of energetic ions in both space and energy showed dynamic change in the energetic ion profile due to collective instabilities. The impact of toroidal plasma rotation on ELM behaviour is clarified in the grassy ELM and QH domains. Retention of hydrogen isotopes in the divertor tiles is analysed.

  3. An alpha2,6-sialyltransferase cloned from Photobacterium leiognathi strain JT-SHIZ-119 shows both sialyltransferase and neuraminidase activity.

    PubMed

    Mine, Toshiki; Katayama, Sakurako; Kajiwara, Hitomi; Tsunashima, Masako; Tsukamoto, Hiroshi; Takakura, Yoshimitsu; Yamamoto, Takeshi

    2010-02-01

    We cloned, expressed, and characterized a novel beta-galactoside alpha2,6-sialyltransferase from Photobacterium leiognathi strain JT-SHIZ-119. The protein showed 56-96% identity to the marine bacterial alpha2,6-sialyltransferases classified into glycosyltransferase family 80. The sialyltransferase activity of the N-terminal truncated form of the recombinant enzyme was 1477 U/L of Escherichia coli culture. The truncated recombinant enzyme was purified as a single band by sodium dodecyl sulfate polyacrylamide gel electrophoresis through 3 column chromatography steps. The enzyme had distinct activity compared with known marine bacterial alpha2,6-sialyltransferases. Although alpha2,6-sialyltransferases cloned from marine bacteria, such as Photobacterium damselae strain JT0160, P. leiognathi strain JT-SHIZ-145, and Photobacterium sp. strain JT-ISH-224, show only alpha2,6-sialyltransferase activity, the recombinant enzyme cloned from P. leiognathi strain JT-SHIZ-119 showed both alpha2,6-sialyltransferase and alpha2,6-linkage-specific neuraminidase activity. Our results provide important information toward a comprehensive understanding of the bacterial sialyltransferases belonging to the group 80 glycosyltransferase family in the CAZy database. PMID:19797322

  4. Density fluctuation measurement using motional Stark effect optics in JT-60U

    SciTech Connect

    Suzuki, T.; Fujita, T.; Oyama, N.; Isayama, A.; Matsunaga, G.; Oikawa, T.; Asakura, N.; Takechi, M.

    2006-10-15

    The multichannel motional Stark effect (MSE) diagnostic system in JT-60U has been upgraded to measure density fluctuation profile. A 16-channel fast-sampling digitizer has been added in order to measure photomultiplier-tube signals at measurement frequency of 0.5-1 MHz. The new system works as a MSE and beam emission spectroscopy diagnostic. Spatially resolved electron density fluctuation profile measurement in various operation regimes is presented. In the core plasma, density fluctuation induced by rotation of tearing mode islands was observed. Temporal evolution of the fluctuation frequency agrees with that measured by Mirnov coils (poloidal and toroidal mode numbers: 2 and 1, respectively). The phases of the fluctuations on either side of the q=2 surface are inverted, which is consistent with electron cyclotron emission. These measurements show that the density fluctuation is caused by a rotating magnetic island structure induced by the tearing mode. In the scrape-off layer of a H-mode plasma with edge-localized-mode (ELM), i. e., ELMy H-mode outward propagation of strong intermittent emission corresponding to ELM crash was also observed. The propagation velocity is 0.69-2.2 km/s along the MSE measurement points, the time lag and distance between adjacent channels being 67{+-}35 {mu}s and 70 mm, respectively.

  5. Performance deterioration based on in-service engine data: JT9D jet engine diagnostics program

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.

    1979-01-01

    Results of analyses of engine performance deterioration trends and levels with respect to service usage are presented. Thirty-two JT9D-7A engines were selected for this purpose. The selection of this engine fleet provided the opportunity of obtaining engine performance data starting before the first flight through initial service such that the trend and levels of engine deterioration related to both short and long term deterioration could be more carefully defined. The performance data collected and analyzed included in-flight, on wing (ground), and test stand prerepair and postrepair performance calibrations with expanded instrumentation where feasible. The results of the analyses of these data were used to: (1) close gaps in previously obtained historical data as well as augment the historical data with more carefully obtained data; (2) refine preliminary models of performance deterioration with respect to usage; (3) establish an understanding of the relationships between ground and altitude performance deterioration trends; (4) refine preliminary recommendations concerning means to reduce and control deterioration; and (5) identify areas where additional effort is required to develop an understanding of complex deterioration issues.

  6. Pulsed-laser ablation of co-deposits on JT-60 graphite tile

    NASA Astrophysics Data System (ADS)

    Sakawa, Youichi; Watanabe, Daisuke; Shibahara, Takahiro; Sugiyama, Kazuyoshi; Tanabe, Tetsuo

    2007-08-01

    Pulsed laser ablation of the co-deposits on a JT-60 open-divertor tile using the fourth harmonic of a 20 ps-Nd: YAG laser has been investigated. With increasing the laser intensity, three regions, non-ablation region (NAR), weak-ablation region (WAR), and strong-ablation region (SAR) were distinguished. Transition from NAR to WAR and WAR to SAR occurred at the threshold laser intensity for laser ablation and that for strong ionization of carbon atoms, respectively. The ablation accompanied desorption of H 2 and C 2H 2, with minor contribution of other hydrocarbons, while production of H 2O was small. In NAR and WAR the number of the hydrogen desorbed by the laser irradiation was less than that of hydrogen retained in the ablated volume, while in SAR it was much larger, owing to thermal desorption of hydrogen gas from the region surrounding the ablated volume. For the ablative removal of hydrogen isotopes, SAR is more desirable because of higher removal efficiency and less production of hydrocarbons.

  7. Performance deterioration based on existing (historical) data; JT9D jet engine diagnostics program

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.

    1978-01-01

    The results of the collection and analysis of historical data pertaining to the deterioration of JT9D engine performance are presented. The results of analyses of prerepair and postrepair engine test stand performance data from a number of airlines to establish the individual as well as average losses in engine performance with respect to service use are included. Analysis of the changes in mechanical condition of parts, obtained by inspection of used gas-path parts of varying age, allowed preliminary assessments of component performance deterioration levels and identification of the causitive factors. These component performance estimates, refined by data from special engine back-to-back testing related to module performance restoration, permitted the development of preliminary models of engine component/module performance deterioration with respect to usage. The preliminary assessment of the causes of module performance deterioration and the trends with usage are explained, along with the role each module plays in overall engine performance deterioration. Preliminary recommendations with respect to operating and maintenance practices which could be adopted to control the level of performance deterioration are presented. The needs for additional component sensitivity testing as well as outstanding issues are discussed.

  8. Performance deterioration due to acceptance testing and flight loads; JT90 jet engine diagnostic program

    NASA Technical Reports Server (NTRS)

    Olsson, W. J.

    1982-01-01

    The results of a flight loads test of the JT9D-7 engine are presented. The goals of this test program were to: measure aerodynamic and inertia loads on the engine during flight, explore the effects of airplane gross weight and typical maneuvers on these flight loads, simultaneously measure the changes in engine running clearances and performance resulting from the maneuvers, make refinements of engine performance deterioration prediction models based on analytical results of the tests, and make recommendations to improve propulsion system performance retention. The test program included a typical production airplane acceptance test plus additional flights and maneuvers to encompass the range of flight loads in revenue service. The test results indicated that aerodynamic loads, primarily at take-off, were the major cause of rub-indicated that aerodynamic loads, primarily at take-off, were the major cause of rub-induced deterioration in the cold sectin of the engine. Differential thermal expansion between rotating and static parts plus aerodynamic loads combined to cause blade-to-seal rubs in the turbine.

  9. Behaviour of tritium in the vacuum vessel of JT-60U

    SciTech Connect

    Kobayashi, K.; Miya, N.; Ikeda, Y.; Torikai, Y.; Saito, M.; Alimov, V.

    2015-03-15

    The disassembly of the JT-60U torus started in 2010 after 18 years of deuterium plasma operations. The vessel is made of Inconel 625. Therefore, it was very important to study the hydrogen isotope (particularly tritium) behavior in Inconel 625 from the viewpoint of the clearance procedure. Inconel 625 specimen was exposed to the D{sub 2} (92.8 %) - T{sub 2} (7.2 %) gas mixture at 573 K for 5 hours. The tritium release from the specimen at 298 K was controlled for about 1 year. After that a part of tritium remaining in the specimen was released by heating up to 1073 K. Other part of tritium trapped in the specimen was measured by chemical etching method. Most of the chemical form of the released tritium was HTO. The contaminated specimen by tritium was released continuously the diffusible tritium under the ambient condition. In the tritium release experiment, the amount of desorbed tritium was about 99% during 1 year. It was considered that the tritium in Inconel 625 was released easily.

  10. Evaluation of heat and particle controllability on the JT-60SA divertor

    NASA Astrophysics Data System (ADS)

    Kawashima, H.; Hoshino, K.; Shimizu, K.; Takizuka, T.; Ide, S.; Sakurai, S.; Asakura, N.

    2011-08-01

    The JT-60SA divertor design has been established on the basis of engineering requirements and physics analysis. Heat and particle fluxes under the full input power of 41 MW can give severe heat loads on the divertor targets, while the allowable heat load is limited below 15 MW/m2. Dependence of the heat flux mitigation on a D2 gas-puff is evaluated by SONIC simulations for high density (ne_ave ˜ 1 × 1020 m-3) high current plasmas. It is found that the peak heat load 10 MW/m2 with dense (ned > 4 × 1020 m-3) and cold (Ted, Tid ⩽ 1 eV) divertor plasmas are obtained at a moderate gas-puff of Γpuff = 15 × 1021 s-1. Divertor plasmas are controlled from attached to detached condition using the divertor pump with pumping-speed below 100 m3/s. In full non-inductive current drive plasmas with low density (ne_ave ˜ 5 × 1019 m-3), the reduction of divertor heat load is achieved with the Ar injection.

  11. Recovery of Retained Tritium from Graphite Tile of JT-60U

    SciTech Connect

    Takeishi, Toshiharu; Katayama, Kazunari; Nishikawa, Masabumi; Miya, Naoyuki; Masaki, Kei

    2005-07-15

    Tritium thermal release and full combustion with oxygen were performed on isotropic graphite tiles used for plasma facing material of JT-60U. Approximately 50-80 % of tritium was released by dry argon gas purge and 20-50 % of tritium was released by humid argon gas purge up to 800-1200 deg. C within one day, respectively. Further several percent of tritium was released by full combustion with oxygen. It was experimentally confirmed that all retained tritium is not released by thermal dry gas purge and by use of isotope exchange reaction at high temperature in such a short period. In the full combustion operation, isotropic graphite begins to combust at higher temperature than 650 deg. C, but effective combustion temperature was higher than 700 deg. C. Since it is very difficult to heat the graphite tile attached on the wall of vacuum vessel at higher than 700 deg. C, it is considered to be not easy to recover all the tritium retained in the graphite while in the vacuum vessel.

  12. Roles of argon seeding in energy confinement and pedestal structure in JT-60U

    NASA Astrophysics Data System (ADS)

    Urano, H.; Nakata, M.; Aiba, N.; Kubo, H.; Honda, M.; Hayashi, N.; Yoshida, M.; Kamada, Y.; the JT-60 Team

    2015-03-01

    The mechanism of improving energy confinement with argon seeding at high density has been investigated in JT-60U. Better confinement is sustained at high density by argon seeding accompanied by higher core and pedestal temperatures. The electron density profiles become flatter with increasing density in conventional H-mode plasmas, whereas peaked density profiles are maintained with argon seeding. Density peaking and dilution effects lower the pedestal density at a given averaged density. The pedestal density in the argon seeded plasmas, which is lower than that in plasmas with deuterium puff, enables the pedestal temperature to be higher, whereas the increase in the pedestal pressure with argon seeding is small. High pedestal temperature is a boundary condition for high core temperature through profile stiffness, which leads to better confinement with argon seeding. The density peaking is a key factor of sustaining better confinement in argon seeded H-mode plasmas. The radiative loss power density is predominantly enhanced in the edge region by argon puff. The role of argon seeding in the pedestal characteristics has also been examined. The pedestal width becomes larger continuously with edge collisionality, but is nearly independent of the presence of argon seeding.

  13. Effect of ceramic coating of JT8D combustor liner on maximum liner temperatures and other combustor performance parameters

    NASA Technical Reports Server (NTRS)

    Butze, H. F.; Liebert, C. H.

    1976-01-01

    The effect of ceramic coating of a JT8D combustor liner was investigated at simulated cruise and takeoff conditions with two fuels of widely different aromatic contents. Substantial decreases in maximum liner temperatures and flame radiation values were obtained with the ceramic-coated liner. Small reductions in exhaust gas smoke concentrations were observed with the ceramic-coated liner. Other performance parameters such as combustion efficiency and emissions of unburned hydrocarbons, CO, and NOx were not affected significantly. No deterioration of the ceramic coating was observed after about 6 hours of cyclic operation including several startups and shutdowns.

  14. Preliminary core-engine noise abatement experimental results of a fluid injection nozzle on a JT-15D turbofan engine

    NASA Technical Reports Server (NTRS)

    Cheng, D. Y.; Wang, P.

    1975-01-01

    Jet noise, as induced by shear stress, in an jet exhaust is investigated. Experiments were performed on a JT-15D fan jet to verify the inward momentum stress reduction concept. The experiments involved making fan air flow convergently around the high velocity core jet with a small angle. Ring airfoils were used as flow separators for the minimization of the thrust loss. Jet exhaust noise reduction of ll db at 30 deg from the jet axis was recorded and 8 db integrated overall noise reduction over a hemisphere was measured with only 4.6% thrust loss, or 152 db/percent thrust loss.

  15. Enhanced performance and control issues in JT-60U long pulse discharges

    NASA Astrophysics Data System (ADS)

    Sakamoto, Y.; JT-60 Team

    2005-12-01

    Recent experimental results are reported on control issues involved in long timescales and enhanced performance in JT-60U. The control issues in neoclassical tearing mode (NTM) suppression in the weak shear plasma regime include background optimization through decreasing βp(Lq/Lp) at the rational surface and active stabilization of NTMs using ECCD. By optimizing βp(Lq/Lp), a condition of βN ~ 2.5 was sustained for 10 times the current profile relaxation time and one of βN ~ 2.4 with qmin ~ 1.5 was sustained for 2.8 times the current profile relaxation time, with nearly full non-inductive current drive. In addition, a condition of βN ~ 3 was sustained for 5.5 s through stabilization of NTMs using ECCD, and an EC driven current nearly equal to the bootstrap current was required for complete stabilization. In the reversed shear plasma regime, the issue is the existence of the steady state solution with a large fBS value. By controlling the pressure gradient at the internal transport barrier through toroidal rotation to avoid the disruption, a large fBS value of approximately 75% was sustained for 2.7 times the current profile relaxation time, with nearly full non-inductive current drive, and a steady-state solution with a large fBS value is confirmed. The control issues for the edge pedestal and edge localized modes (ELMs) are control of the pedestal pressure and the energy loss through ELMs. The pedestal pressure increases by >40% through the change in toroidal rotation. The type of ELM can be controlled by toroidal rotation from type-I to grassy.

  16. Stabilization of neoclassical tearing mode by ECCD and its evolution simulation on JT-60U tokamak

    NASA Astrophysics Data System (ADS)

    Nagasaki, K.; Isayama, A.; Hayashi, N.; Ozeki, T.; Takechi, M.; Oyama, N.; Ide, S.; Yamamoto, S.; JT-60 Team

    2005-12-01

    Stabilization of an m = 3/n = 2 neoclassical tearing mode (NTM) by a local electron cyclotron current drive (ECCD) has been studied in high βp ELMy H-mode plasmas in the JT-60U tokamak. In the stabilization experiment, the electron cyclotron (EC) injection timing is scanned from the 'before mode onset' phase (preemptive ECCD) to the mode saturation phase (late ECCD). It has been demonstrated that the ECCD is more effective when it is applied before the mode onset and the critical timing for effective ECCD is related to the mode excitation phase. The EC power to prevent the 3/2 NTM excitation by preemptive ECCD is lower by about 20% compared with complete stabilization by late ECCD. Even when the 3/2 NTM is excited, the stabilization effect is stronger than for late ECCD. For a high performance plasma of the normalized beta, βN = 3.0, the H-factor H89PL improves from 1.9 to 2.1 when the 3/2 NTM is suppressed. A numerical study has been made based on the modified Rutherford equation coupled with a 1.5D transport code and an EC code. The simulation reproduces well the time evolution of the magnetic island both at the growing and stabilizing phases. The simulation results show that it is important to adjust not only the EC current position but also its width to stabilize the NTM effectively. The reduction of EC power for NTM prevention in experiments for preemptive ECCD can be explained by the increase of the minimum seed island size for NTM excitation. This manuscript is based on the paper EX/7-4 presented at the 20th IAEA Fusion Energy Conference, Vilamoura, Portugal.

  17. Development and Operation of the Lower Hybrid Range of Frequency System on JT-60U

    SciTech Connect

    Seki, M.; Ikeda, Y.; Maebara, S.; Moriyama, S.; Naito, O.; Anno, K.; Hiranai, S.; Shimono, M.; Shinozaki, S.; Terakado, M.; Yokokura, K.; Yamamoto, T.; Fujii, T.

    2002-09-15

    Development and operation of a lower hybrid range of frequency (LHRF) system for JT-60U are presented. The LHRF system was constructed in 1986 to study current drive and plasma heating at high injection power. Its main specifications are the total output power 24 MW with 24 high power klystrons, the frequency 1.74 to 2.23 GHz, and the injection power {approx}10 MW with three conventional antennas. To improve the antenna capabilities such as the current drive efficiency, N{sub //peak} controllability and the power injection properties, a 3-divided multi-junction type (CD1' launcher) and a 12-divided multi-junction type (CD2 launcher) are developed. The CD2 launcher can also reduce the number of the transmission lines to one fourth of the original system. The injection power {approx}7 MW is attained, and then the highest current drive efficiency 3.5 x 10{sup 19} m{sup -2}AW{sup -1} and the highest non-inductive driven current 3.6 MA are achieved. The high power klystron capable of the cathode-heater operation times more than 3000 hours is improved. The outgassing rate is estimated with the CD2 launcher as 1-10 x 10{sup -6} Pam{sup 3}/sm{sup 2}, which is sufficiently small not to need the vacuum pumping system for the launcher. Heat load onto the launcher due to the ripple enhanced banana drift loss is first observed in NBI or ICRF heating. From investigation on antenna-plasma coupling, the gas puffing improves distant coupling.

  18. Development of a closed-loop J-T cryoablation device with a long cooling area and multiple expansion parts.

    PubMed

    Lee, Cheonkyu; Baek, Seungwhan; Lee, Jisung; Hwang, Gyuwan; Jeong, Sangkwon; Park, Sang Woo

    2014-11-01

    Cryoablation is a surgical procedure used to freeze defective cells by inserting a low temperature probe into a human body to destroy malignant tissues. Miniaturized Joule-Thomson (J-T) refrigerators are often used to minimize the volume of the cooling device and reduce the destruction zone of normal tissue. The cooling effects of the existing probes are not uniformly generated along the longitudinal direction of the probe, which makes their applications less effective in surgeries of incompetent great saphenous veins (GSVs), where the target cells are distributed over a broad range. Long uniform refrigeration is required across the entire area of the probe to apply the same cooling effects. In this paper, a closed-loop J-T cryoablation probe was designed and fabricated to provide uniform refrigeration over a large area, with multiple expansion parts. Using flow boiling heat transfer, uniform cooling of a 200 mm-long and 0.3 mm thickness piece of target tissue was possible and simulated in a gelatin solution. The developed probe produced a greater than 53 K min(-1) cooling rate and the cooling temperature was below 253 K to satisfy the required cell death conditions. PMID:25164379

  19. Expanded study of feasibility of measuring in-flight 747/JT9D loads, performance, clearance, and thermal data

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.; Martin, R. L.

    1980-01-01

    The JT9D jet engine exhibits a TSFC loss of about 1 percent in the initial 50 flight cycles of a new engine. These early losses are caused by seal-wear induced opening of running clearances in the engine gas path. The causes of this seal wear have been identified as flight induced loads which deflect the engine cases and rotors, causing the rotating blades to rub against the seal surfaces, producing permanent clearance changes. The real level of flight loads encountered during airplane acceptance testing and revenue service and the engine's response in the dynamic flight environment were investigated. The feasibility of direct measurement of these flight loads and their effects by concurrent measurement of 747/JT9D propulsion system aerodynamic and inertia loads and the critical engine clearance and performance changes during 747 flight and ground operations was evaluated. A number of technical options were examined in relation to the total estimated program cost to facilitate selection of the most cost effective option. It is concluded that a flight test program meeting the overall objective of determining the levels of aerodynamic and inertia load levels to which the engine is exposed during the initial flight acceptance test and normal flight maneuvers is feasible and desirable. A specific recommended flight test program, based on the evaluation of cost effectiveness, is defined.

  20. Purification, crystallization and preliminary crystallographic characterization of the α2,6-sialyltransferase from Photobacterium sp. JT-ISH-224

    SciTech Connect

    Okino, Nozomu; Kakuta, Yoshimitsu; Kajiwara, Hitomi; Ichikawa, Masako; Takakura, Yoshimitsu; Ito, Makoto; Yamamoto, Takeshi

    2007-08-01

    Crystallization of the α2,6-sialyltransferase from Photobacterium. Sialyltransferases transfer sialic acid from cytidine-5-monophospho-N-acetylneuraminic acid (CMP-NeuAc) to the nonreducing termini of the oligosaccharyl structures of various glycoproteins and glycolipids. The newly cloned α2,6-sialyltransferase from Photobacterium sp. JT-ISH-224 (from the Vibrionaceae family) is composed of two domains: an unknown N-terminal domain and a catalytic C-terminal domain which shares significant homology with the Pasteurella multocida multifunctional sialyltransferase. The putative mature form of JT-ISH-224 α2,6-sialyltransferase was overproduced in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method at 293 K. The crystal belonged to space group P3{sub 1}21 or P3{sub 2}21, with unit-cell parameters a = b = 90.29, c = 204.33 Å. X-ray diffraction data were collected to 2.5 Å resolution.

  1. Active Control of Inlet Noise on the JT15D Turbofan Engine

    NASA Technical Reports Server (NTRS)

    Smith, Jerome P.; Hutcheson, Florence V.; Burdisso, Ricardo A.; Fuller, Chris R.

    1999-01-01

    This report presents the key results obtained by the Vibration and Acoustics Laboratories at Virginia Tech over the year from November 1997 to December 1998 on the Active Noise Control of Turbofan Engines research project funded by NASA Langley Research Center. The concept of implementing active noise control techniques with fuselage-mounted error sensors is investigated both analytically and experimentally. The analytical part of the project involves the continued development of an advanced modeling technique to provide prediction and design guidelines for application of active noise control techniques to large, realistic high bypass engines of the type on which active control methods are expected to be applied. Results from the advanced analytical model are presented that show the effectiveness of the control strategies, and the analytical results presented for fuselage error sensors show good agreement with the experimentally observed results and provide additional insight into the control phenomena. Additional analytical results are presented for active noise control used in conjunction with a wavenumber sensing technique. The experimental work is carried out on a running JT15D turbofan jet engine in a test stand at Virginia Tech. The control strategy used in these tests was the feedforward Filtered-X LMS algorithm. The control inputs were supplied by single and multiple circumferential arrays of acoustic sources equipped with neodymium iron cobalt magnets mounted upstream of the fan. The reference signal was obtained from an inlet mounted eddy current probe. The error signals were obtained from a number of pressure transducers flush-mounted in a simulated fuselage section mounted in the engine test cell. The active control methods are investigated when implemented with the control sources embedded within the acoustically absorptive material on a passively-lined inlet. The experimental results show that the combination of active control techniques with fuselage-mounted error sensors and passive control techniques is an effective means of reducing radiated noise from turbofan engines. Strategic selection of the location of the error transducers is shown to be effective for reducing the radiation towards particular directions in the farfield. An analytical model is used to predict the behavior of the control system and to guide the experimental design configurations, and the analytical results presented show good agreement with the experimentally observed results.

  2. Investigation of performance deterioration of the CF6/JT9D, high-bypass ratio turbofan engines

    NASA Technical Reports Server (NTRS)

    Ziemianski, J. A.; Mehalic, C. M.

    1980-01-01

    The aircraft energy efficiency program within NASA is developing technology required to improve the fuel efficiency of commercial subsonic transport aricraft. One segment of this program includes engine diagnostics which is directed toward determining the sources and causes of performance deterioration in the Pratt and Whitney Aircraft JT9D and General Electric CF6 high-bypass ratio turbofan engines and developing technology for minimizing the performance losses. Results of engine performance deterioration investigations based on historical data, special engine tests, and specific tests to define the influence of flight loads and component clearances on performance are presented. The results of analysis of several damage mechanisms that contribute to performance deterioration such as blade tip rubs, airfoil surface roughness and erosion, and thermal distortion are also included. The significance of these damage mechanisms on component and overall engine performance is discussed.

  3. Unsteady fan blade pressure and acoustic radiation from a JT15D-1 turbofan engine at simulated forward speed

    NASA Technical Reports Server (NTRS)

    Preisser, J. S.; Schoenster, J. A.; Golub, R. A.; Horne, C.

    1981-01-01

    Tests have been conducted on a JT15D-1 turbofan engine both statically and at simulated forward speed in the Ames 12 x 24 Meter Wind Tunnel. Both far-field acoustic data and unsteady pressure data from transducers mounted on the fan blades were acquired. Results showed a sound power reduction of about 10 dB in the far-field acoustic levels with simulated forward speed over those measured without forward speed. Blade mounted transducer results showed rotor-turbulence interaction dominated the noise field at very low speeds while an interaction between the rotor and internal struts dominated at higher speeds. Results are presented to show the effects of varying engine rpm, changing the angle-of-attack of the engine inlet to tunnel flow and mounting an aircraft wing to simulate an installation condition on an actual aircraft.

  4. Numerical modeling of a 2 K J-T heat exchanger used in Fermilab Vertical Test Stand VTS-1

    NASA Astrophysics Data System (ADS)

    Gupta, Prabhat Kumar; Rabehl, Roger

    2014-07-01

    Fermilab Vertical Test Stand-1 (VTS-1) has been in operation since 2007 for testing superconducting radio frequency (SCRF) cavities at 2 K. This test stand includes a heat exchanger consisting of a single layer; helically wound finned tube, upstream of the J-T valve. A finite difference thermal model has been developed in Engineering Equation Solver (EES) to study the thermal performance of this heat exchanger during refilling of the test stand. The model can predict heat exchanger performance under various other operating conditions and is therefore useful as a design tool for similar heat exchangers in other facilities. The present paper discusses the different operational modes of this heat exchanger and its thermal characteristics under these operational modes. Results of this model have been compared with experimental data gathered from the VTS-1 heat exchanger, and they are in good agreement with the present model.

  5. JT9D-70/59 Improved High Pressure Turbine Active Clearance Control System. [for specific fuel consumption improvement

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1979-01-01

    The JT9D-70/59 high pressure turbine active clearance control system was modified to provide reduction of blade tip clearance when the system is activated during cruise operation. The modification increased the flow capacity and air impingement effectiveness of the cooling air manifold to augment turbine case shrinkage capability, and increased responsiveness of the airseal clearance to case shrinkage. The simulated altitude engine testing indicated a significant improvement in specific fuel consumption with the modified system. A 1000 cycle engine endurance test showed no unusual wear or performance deterioration effects on the engine or the clearance control system. Rig tests indicated that the air impingement and seal support configurations used in the engine tests are near optimum.

  6. Numerical modeling of a 2K J-T heat exchanger used in Fermilab Vertical Test Stand VTS-1

    SciTech Connect

    Gupta, Prabhat Kumar; Rabehl, Roger

    2014-07-01

    Fermilab Vertical Test Stand-1 (VTS-1) is in operation since 2007 for testing the superconducting RF cavities at 2 K. This test stand has single layer coiled finned tubes heat exchanger before J-T valve. A finite difference based thermal model has been developed in Engineering Equation Solver (EES) to study its thermal performance during filling and refilling to maintain the constant liquid level of test stand. The model is also useful to predict its performance under other various operating conditions and will be useful to design the similar kind of heat exchanger for future needs. Present paper discusses the different operational modes of this heat exchanger and its thermal characteristics under these operational modes. Results of this model have also been compared with the experimental data gathered from the VTS-1 heat exchanger and they are in good agreement with the present model.

  7. Conductor and joint test results of JT-60SA CS and EF coils using the NIFS test facility

    NASA Astrophysics Data System (ADS)

    Obana, Tetsuhiro; Takahata, Kazuya; Hamaguchi, Shinji; Kizu, Kaname; Murakami, Haruyuki; Chikaraishi, Hirotaka; Noguchi, Hiroki; Kobuchi, Takashi; Moriuchi, Sadatomo; Imagawa, Shinsaku; Mito, Toshiyuki; Tsuchiya, Katsuhiko; Natsume, Kyohei; Yoshida, Kiyoshi; Nomoto, Kazuhiro; Kim, Tae-hyun

    2016-01-01

    In 2007, JAEA and NIFS launched the test project to evaluate the performance of cable-in-conduit (CIC) conductors and conductor joints for the JT-60SA CS and EF coils. In this project, conductor tests for four types of coil conductor and joint tests for seven types of conductor joint have been conducted for the past eight years using the NIFS test facility. As a result, the test project indicated that the CIC conductors and conductor joints fulfill the design requirement for the CS and EF coils. In addition, the NIFS test facility is expected to be utilized as the test facility for the development of a conductor and conductor joint for the purpose of the DEMO nuclear fusion power plant, provided that the required magnetic field strength is within 9 T.

  8. Role of convective amplification of n = 1 energetic particle modes for N-NB ion dynamics in JT-60U

    NASA Astrophysics Data System (ADS)

    Bierwage, A.; Shinohara, K.; Aiba, N.; Todo, Y.

    2013-07-01

    The hybrid code MEGA is used to simulate an abrupt large-amplitude event (ALE) in JT-60U shot E039672 that was strongly driven by a pair of negative-ion-based neutral beams (N-NBs). This configuration is known to be unstable to energetic particle modes (EPMs) with toroidal mode number n = 1. The purpose of this study is to look for a threshold with respect to the on-axis fast ion beta value, βh0, beyond which the EPM undergoes convective amplification (CA) and causes significant fast ion transport. This is motivated by the hypothesis that such a threshold may work as a trigger mechanism for relaxation events, such as ALE. In order to facilitate quantitative comparisons with the experiment, a realistic geometry and bulk pressure is used. Furthermore, MEGA is initialized with a fast ion distribution computed for JT-60U by an orbit-following Monte-Carlo code, and a passive vacuum region allows particles to travel without encountering artificial loss boundaries. Consistently with the experiment, the simulation predicts a burst time of about 0.3 ms and peak magnetic fluctuation levels around δBϑ/B < 10-3 at the plasma boundary. As βh0 is increased, a gradual increase in the CA of the EPM and in the convective transport of both resonant and nonresonant particles is found. The absence of a sharp transition between low- and high-amplitude fluctuations leads to the conclusion that the onset of CA does not suffice as a trigger mechanism for ALE.

  9. Beamlet deflection due to beamlet-beamlet interaction in a large-area multiaperture negative ion source for JT-60U

    SciTech Connect

    Kamada, M.; Hanada, M.; Ikeda, Y.; Grisham, L. R.; Jiang, W.

    2008-02-15

    The JT-60U negative ion source has been designed to produce high current beams of 22 A through grids of 1080 apertures (five segments with nine rows of 24 apertures). One of the key issues is to steer such a high current beam through the multiaperture grids in order to focus the overall beam envelope because the beamlet-beamlet interaction may deflect the outer beamlets outward due to unbalanced space charge repulsion. To clarify the beam deflection in the JT-60U negative ion source, the beamlet trajectory in a multiaperture ion source was calculated by a three-dimensional simulation code. The measured angles of the outmost beamlets were in agreement with the calculated results where space charge of the beamlets was taken into account. It is noticed that the deflection of the outermost beamlet due to the beamlet-beamlet interaction is saturated at 5.2 mrad outward for beamlets more than ten.

  10. Titanium honeycomb acoustic lining structural and thermal test report. [for acoustic tailpipe for JT8D engine

    NASA Technical Reports Server (NTRS)

    Joynes, D.; Balut, J. P.

    1974-01-01

    The results are presented of static, fatigue and thermal testing of titanium honeycomb acoustic panels representing the acoustic tailpipe for the Pratt and Whitney Aircraft JT8D Refan engine which is being studied for use on the Boeing 727-200 airplane. Test specimens represented the engine and tailpipe flange joints, the rail to which the thrust reverser is attached and shear specimens of the tailpipe honeycomb. Specimens were made in four different batches with variations in configuration, materials and processes in each. Static strength of all test specimens exceeded the design ultimate load requirements. Fatigue test results confirmed that aluminum brazed titanium, as used in the Refan tailpipe design, meets the fatigue durability objectives. Quality of welding was found to be critical to life, with substandard welding failing prematurely, whereas welding within the process specification exceeded the panel skin life. Initial fatigue testing used short grip length bolts which failed prematurely. These were replaced with longer bolts and subsequent testing demonstrated the required life. Thermal tests indicate that perforated skin acoustic honeycomb has approximately twice the heat transfer of solid skin honeycomb.

  11. Detailed in situ laser calibration of the infrared imaging video bolometer for the JT-60U tokamak

    SciTech Connect

    Parchamy, H.; Peterson, B. J.; Konoshima, S.; Hayashi, H.; Seo, D. C.; Ashikawa, N

    2006-10-15

    The infrared imaging video bolometer (IRVB) in JT-60U includes a single graphite-coated gold foil with an effective area of 9x7 cm{sup 2} and a thickness of 2.5 {mu}m. The thermal images of the foil resulting from the plasma radiation are provided by an IR camera. The calibration technique of the IRVB gives confidence in the absolute levels of the measured values of the plasma radiation. The in situ calibration is carried out in order to obtain local foil properties such as the thermal diffusivity {kappa} and the product of the thermal conductivity k and the thickness t{sub f} of the foil. These quantities are necessary for solving the two-dimensional heat diffusion equation of the foil which is used in the experiments. These parameters are determined by comparing the measured temperature profiles (for kt{sub f}) and their decays (for {kappa}) with the corresponding results of a finite element model using the measured HeNe laser power profile as a known radiation power source. The infrared camera (Indigo/Omega) is calibrated by fitting the temperature rise of a heated plate to the resulting camera data using the Stefan-Boltzmann law.

  12. Optical designs of reflection and refraction collection optics for a JT-60SA core Thomson scattering system

    NASA Astrophysics Data System (ADS)

    Tojo, H.; Hatae, T.; Hamano, T.; Sakuma, T.; Itami, K.

    2013-09-01

    Collection optics for core measurements in a JT-60SA Thomson scattering system were designed. The collection optics will be installed in a limited space and have a wide field of view and wide wavelength range. Two types of the optics are therefore suggested: refraction and reflection types. The reflection system, with a large primary mirror, avoids large chromatic aberrations. Because the size limit of the primary mirror and vignetting due to the secondary mirror affect the total collection throughput, conditions that provide the high throughput are found through an optimization. A refraction system with four lenses forming an Ernostar system is also employed. The use of high-refractive-index glass materials enhances the freedom of the lens curvatures, resulting in suppression of the spherical and coma aberration. Moreover, sufficient throughput can be achieved, even with smaller lenses than that of a previous design given in [H. Tojo, T. Hatae, T. Sakuma, T. Hamano, K. Itami, Y. Aida, S. Suitoh, and D. Fujie, Rev. Sci. Instrum. 81, 10D539 (2010)]. The optical resolutions of the reflection and refraction systems are both sufficient for understanding the spatial structures in plasma. In particular, the spot sizes at the image of the optics are evaluated as {˜}0.3 mm and {˜}0.4 mm, respectively. The throughput for the two systems, including the pupil size and transmissivity, are also compared. The results show that good measurement accuracy (<10%) even at high electron temperatures ({<}30 keV) can be expected in the refraction system.

  13. Aerodynamic performance of 0.4066-scale model of JT8D refan stage with S-duct inlet

    NASA Technical Reports Server (NTRS)

    Moore, R. D.; Kovich, G.; Lewis, G. W., Jr.

    1977-01-01

    A scale model of the JT8D refan stage was tested with a scale model of the S-duct inlet design for the refanned Boeing 727 center engine. Detailed survey data of pressures, temperatures, and flow angles were obtained over a range of flows at speeds from 70 to 97 percent of design speed. Two S-duct configurations were tested; one with a bellmouth inlet and the other with a flight lip inlet. The results indicated that the overall performance was essentially unaffected by the distortion generated by the S-duct inlet. The stall weight flow increased by less than 0.5 kg/sec (approximately 1.5% of design flow) with the S-duct inlet compared with that obtained with uniform flow. The detailed measurements indicated that the inlet guide vane (IGV) significantly reduced circumferential variations. For example, the flow angles ahead of the IGV were positive in the right half of the inlet and negative in the left half. Behind the IGV, the flow angles tended to be more uniform circumferentially.

  14. Long-pulse production of high current negative ion beam by using actively temperature controlled plasma grid for JT-60SA negative ion source

    SciTech Connect

    Kojima, A.; Hanada, M.; Yoshida, M.; Umeda, N.; Hiratsuka, J.; Kashiwagi, M.; Tobari, H.; Watanabe, K.; Grisham, L. R.

    2015-04-08

    The temperature control system of the large-size plasma grid has been developed to realize the long pulse production of high-current negative ions for JT-60SA. By using this prototype system for the JT-60SA ion source, 15 A negative ions has been sustained for 100 s for the first time, which is three times longer than that obtained in JT-60U. In this system, a high-temperature fluorinated fluid with a high boiling point of 270 degree Celsius is circulated in the cooling channels of the plasma grids (PG) where a cesium (Cs) coverage is formed to enhance the negative ion production. Because the PG temperature control had been applied to only 10% of the extraction area previously, the prototype PG with the full extraction area (110 cm × 45 cm) was developed to increase the negative ion current in this time. In the preliminary results of long pulse productions of high-current negative ions at a Cs conditioning phase, the negative ion production was gradually degraded in the last half of 100 s pulse where the temperature of an arc chamber wall was not saturated. From the spectroscopic measurements, it was found that the Cs flux released from the wall might affect to the negative ion production, which implied the wall temperature should be kept low to control the Cs flux to the PG for the long-pulse high-current production. The obtained results of long-pulse production and the PG temperature control method contributes the design of the ITER ion source.

  15. Long-pulse production of high current negative ion beam by using actively temperature controlled plasma grid for JT-60SA negative ion source

    NASA Astrophysics Data System (ADS)

    Kojima, A.; Hanada, M.; Yoshida, M.; Umeda, N.; Hiratsuka, J.; Kashiwagi, M.; Tobari, H.; Watanabe, K.; Grisham, L. R.

    2015-04-01

    The temperature control system of the large-size plasma grid has been developed to realize the long pulse production of high-current negative ions for JT-60SA. By using this prototype system for the JT-60SA ion source, 15 A negative ions has been sustained for 100 s for the first time, which is three times longer than that obtained in JT-60U. In this system, a high-temperature fluorinated fluid with a high boiling point of 270 degree Celsius is circulated in the cooling channels of the plasma grids (PG) where a cesium (Cs) coverage is formed to enhance the negative ion production. Because the PG temperature control had been applied to only 10% of the extraction area previously, the prototype PG with the full extraction area (110 cm 45 cm) was developed to increase the negative ion current in this time. In the preliminary results of long pulse productions of high-current negative ions at a Cs conditioning phase, the negative ion production was gradually degraded in the last half of 100 s pulse where the temperature of an arc chamber wall was not saturated. From the spectroscopic measurements, it was found that the Cs flux released from the wall might affect to the negative ion production, which implied the wall temperature should be kept low to control the Cs flux to the PG for the long-pulse high-current production. The obtained results of long-pulse production and the PG temperature control method contributes the design of the ITER ion source.

  16. Optical designs of reflection and refraction collection optics for a JT-60SA core Thomson scattering system

    SciTech Connect

    Tojo, H.; Hatae, T.; Hamano, T.; Sakuma, T.; Itami, K.

    2013-09-15

    Collection optics for core measurements in a JT-60SA Thomson scattering system were designed. The collection optics will be installed in a limited space and have a wide field of view and wide wavelength range. Two types of the optics are therefore suggested: refraction and reflection types. The reflection system, with a large primary mirror, avoids large chromatic aberrations. Because the size limit of the primary mirror and vignetting due to the secondary mirror affect the total collection throughput, conditions that provide the high throughput are found through an optimization. A refraction system with four lenses forming an Ernostar system is also employed. The use of high-refractive-index glass materials enhances the freedom of the lens curvatures, resulting in suppression of the spherical and coma aberration. Moreover, sufficient throughput can be achieved, even with smaller lenses than that of a previous design given in [H. Tojo, T. Hatae, T. Sakuma, T. Hamano, K. Itami, Y. Aida, S. Suitoh, and D. Fujie, Rev. Sci. Instrum. 81, 10D539 (2010)]. The optical resolutions of the reflection and refraction systems are both sufficient for understanding the spatial structures in plasma. In particular, the spot sizes at the image of the optics are evaluated as ∼0.3 mm and ∼0.4 mm, respectively. The throughput for the two systems, including the pupil size and transmissivity, are also compared. The results show that good measurement accuracy (<10%) even at high electron temperatures (<30 keV) can be expected in the refraction system.

  17. Design and development of a four-cell sorption compressor based J-T cooler using R134a as working fluid

    SciTech Connect

    Mehta, R. N.; Bapat, S. L.; Atrey, M. D.

    2014-01-29

    The need of a cooler with no electromagnetic interference and practically zero vibration has led to sorption compressor based Joule-Thomson (J-T) coolers. These are useful for sophisticated electronic, ground based and space borne systems. In a Sorption compressor, adsorbed gases are desorbed into a confined volume by raising temperature of the sorption bed resulting in an increase in pressure of the liberated gas. In order to have the system (compressor) functioning on a continuous basis, with almost a constant gas flow rate, multiple cells are used with the adaptation of Temperature Swing Adsorption (TSA) process. As the mass of the desorbed gas dictates the compressor throughput, a combination of sorbent material with high adsorption capacity for a chosen gas or gas mixture has to be selected for efficient operation of the compressor. Commercially available (coconut-shell base) activated carbon has been selected for the present application. The characterization study for variation of discharge pressure is used to design the Four-cell sorption compressor based cryocooler with a desired output. Apart from compressor, the system includes a) After cooler b) Return gas heat exchanger c) capillary tube as the J-T expansion device and d) Evaporator.

  18. Design and development of a four-cell sorption compressor based J-T cooler using R134a as working fluid

    NASA Astrophysics Data System (ADS)

    Mehta, R. N.; Bapat, S. L.; Atrey, M. D.

    2014-01-01

    The need of a cooler with no electromagnetic interference and practically zero vibration has led to sorption compressor based Joule-Thomson (J-T) coolers. These are useful for sophisticated electronic, ground based and space borne systems. In a Sorption compressor, adsorbed gases are desorbed into a confined volume by raising temperature of the sorption bed resulting in an increase in pressure of the liberated gas. In order to have the system (compressor) functioning on a continuous basis, with almost a constant gas flow rate, multiple cells are used with the adaptation of Temperature Swing Adsorption (TSA) process. As the mass of the desorbed gas dictates the compressor throughput, a combination of sorbent material with high adsorption capacity for a chosen gas or gas mixture has to be selected for efficient operation of the compressor. Commercially available (coconut-shell base) activated carbon has been selected for the present application. The characterization study for variation of discharge pressure is used to design the Four-cell sorption compressor based cryocooler with a desired output. Apart from compressor, the system includes a) After cooler b) Return gas heat exchanger c) capillary tube as the J-T expansion device and d) Evaporator.

  19. Integrated modelling of toroidal rotation with the 3D non-local drift-kinetic code and boundary models for JT-60U analyses and predictive simulations

    NASA Astrophysics Data System (ADS)

    Honda, M.; Satake, S.; Suzuki, Y.; Yoshida, M.; Hayashi, N.; Kamiya, K.; Matsuyama, A.; Shinohara, K.; Matsunaga, G.; Nakata, M.; Ide, S.; Urano, H.

    2015-07-01

    The integrated simulation framework for toroidal momentum transport is developed, which self-consistently calculates the neoclassical toroidal viscosity (NTV), the radial electric field {{E}r} and the resultant toroidal rotation {{V}?} together with the scrape-off-layer (SOL) physics-based boundary model. The coupling of three codes, the 1.5D transport code TOPICS, the three-dimensional (3D) equilibrium code VMEC and the 3D ? f drift-kinetic equation solver FORTEC-3D, makes it possible to calculate the NTV due to the non-axisymmetric perturbed magnetic field caused by toroidal field coils. Analyses reveal that the NTV significantly influences {{V}?} in JT-60U and {{E}r} holds the key to determine the NTV profile. The sensitivity of the {{V}?} profile to the boundary rotation necessitates a boundary condition modelling for toroidal momentum. Owing to the high-resolution measurement system in JT-60U, the {{E}r} gradient is found to be virtually zero at the separatrix regardless of toroidal rotation velocities. Focusing on {{E}r} , the boundary model of toroidal momentum is developed in conjunction with the SOL/divertor plasma code D5PM. This modelling realizes self-consistent predictive simulations for operation scenario development in ITER.

  20. Temporal and spatial responses of temperature, density and rotation to electron cyclotron heating in JT-60U

    NASA Astrophysics Data System (ADS)

    Yoshida, M.; Ide, S.; Takenaga, H.; Honda, M.; Urano, H.; Kobayashi, T.; Nakata, M.; Miyato, N.; Kamada, Y.

    2013-08-01

    The temporal and spatial responses of electron channels (the electron density, ne, and the electron temperature, Te) and ion channels (the ion temperature, Ti, and the toroidal rotation velocity, Vφ) to central electron cyclotron heating (ECH) have been investigated in positive shear H-mode plasmas with a relatively peaked Ti profile and internal transport barrier (ITB) plasmas on JT-60U. Ion temperature decreases with ECH after the increase in the electron temperature in the core region. The time scale of the change in Ti is ≈30-60 ms in H-mode plasmas and almost constant in radius. In ITB plasmas, the time scale is shorter around the ITB foot and becomes longer inside the ITB foot. The experimentally measured causality indicates that the decrease in Ti is consistent with the ion temperature gradient critical gradient reduction. This is also verified through a comparison with linear gyrokinetic stability analyses. The electron heat diffusivity increases with ECH in both H-mode and ITB plasmas, correlating to the increase in the ion heat diffusivity. Electron density with a relatively flat ne profile does not decrease with ECH. On the other hand, the electron density with a peaked ne profile decreases with ECH. The flattening of the ne profile is observed after the increase in the electron temperature in the core region. The time scale of the change in ne is about 200-350 ms. Linear gyrokinetic stability analyses imply that the growth rate of the trapped electron modes, which increase outward particle flux, becomes more pronounced during ECH. The counter intrinsic rotation with ECH is identified on H-mode plasmas with a small torque input (BAL-NBI). The counter intrinsic rotation is generated after the increase in the electron temperature and correlates to the change in the electron temperature with ECH around the EC deposition. The radial region where the counter intrinsic rotation is observed is wider than the radial region where the electron temperature varies with ECH. The time scale of the change in the toroidal rotation velocity is about 90-200 ms around the ECH deposition and longer than the time scale of the change in Te and Ti.

  1. Improvement of uniformity of the negative ion beams by tent-shaped magnetic field in the JT-60 negative ion source

    SciTech Connect

    Yoshida, Masafumi Hanada, Masaya; Kojima, Atsushi; Kashiwagi, Mieko; Akino, Noboru; Endo, Yasuei; Komata, Masao; Mogaki, Kazuhiko; Nemoto, Shuji; Ohzeki, Masahiro; Seki, Norikazu; Sasaki, Shunichi; Shimizu, Tatsuo; Terunuma, Yuto; Grisham, Larry R.

    2014-02-15

    Non-uniformity of the negative ion beams in the JT-60 negative ion source with the world-largest ion extraction area was improved by modifying the magnetic filter in the source from the plasma grid (PG) filter to a tent-shaped filter. The magnetic design via electron trajectory calculation showed that the tent-shaped filter was expected to suppress the localization of the primary electrons emitted from the filaments and created uniform plasma with positive ions and atoms of the parent particles for the negative ions. By modifying the magnetic filter to the tent-shaped filter, the uniformity defined as the deviation from the averaged beam intensity was reduced from 14% of the PG filter to ∼10% without a reduction of the negative ion production.

  2. Effect of resistivity profile on current decay time of initial phase of current quench in neon-gas-puff inducing disruptions of JT-60U

    SciTech Connect

    Kawakami, S.; Ohno, N.; Shibata, Y.; Isayama, A.; Kawano, Y.; Watanabe, K. Y.; National Institute for Fusion Science, Toki 509-5292 ; Takizuka, T.; Okamoto, M.

    2013-11-15

    According to an early work [Y. Shibata et al., Nucl. Fusion 50, 025015 (2010)] on the behavior of the plasma current decay in the JT-60U disruptive discharges caused by the radiative collapse with a massive neon-gas-puff, the increase of the internal inductance mainly determined the current decay time of plasma current during the initial phase of current quench. To investigate what determines the increase of the internal inductance, we focus attention on the relationship between the electron temperature (or the resistivity) profile and the time evolution of the current density profile and carry out numerical calculations. As a result, we find the reason of the increase of the internal inductance: The current density profile at the start of the current quench is broader than an expected current density profile in the steady state, which is determined by the temperature (or resistivity) profile. The current density profile evolves into peaked one and the internal inductance is increasing.

  3. Improvement of uniformity of the negative ion beams by tent-shaped magnetic field in the JT-60 negative ion source.

    PubMed

    Yoshida, Masafumi; Hanada, Masaya; Kojima, Atsushi; Kashiwagi, Mieko; Grisham, Larry R; Akino, Noboru; Endo, Yasuei; Komata, Masao; Mogaki, Kazuhiko; Nemoto, Shuji; Ohzeki, Masahiro; Seki, Norikazu; Sasaki, Shunichi; Shimizu, Tatsuo; Terunuma, Yuto

    2014-02-01

    Non-uniformity of the negative ion beams in the JT-60 negative ion source with the world-largest ion extraction area was improved by modifying the magnetic filter in the source from the plasma grid (PG) filter to a tent-shaped filter. The magnetic design via electron trajectory calculation showed that the tent-shaped filter was expected to suppress the localization of the primary electrons emitted from the filaments and created uniform plasma with positive ions and atoms of the parent particles for the negative ions. By modifying the magnetic filter to the tent-shaped filter, the uniformity defined as the deviation from the averaged beam intensity was reduced from 14% of the PG filter to ∼10% without a reduction of the negative ion production. PMID:24593591

  4. Dynamics of energetic particle driven modes and MHD modes in wall-stabilized high-β plasmas on JT-60U and DIII-D

    NASA Astrophysics Data System (ADS)

    Matsunaga, G.; Okabayashi, M.; Aiba, N.; Boedo, J. A.; Ferron, J. R.; Hanson, J. M.; Hao, G. Z.; Heidbrink, W. W.; Holcomb, C. T.; In, Y.; Jackson, G. L.; Liu, Y. Q.; Luce, T. C.; McKee, G. R.; Osborne, T. H.; Pace, D. C.; Shinohara, K.; Snyder, P. B.; Solomon, W. M.; Strait, E. J.; Turnbull, A. D.; Van Zeeland, M. A.; Watkins, J. G.; Zeng, L.; the DIII-D Team; the JT-60 Team

    2013-12-01

    In the wall-stabilized high-β plasmas in JT-60U and DIII-D, interactions between energetic particle (EP) driven modes (EPdMs) and edge localized modes (ELMs) have been observed. The interaction between the EPdM and ELM are reproducibly observed. Many EP diagnostics indicate a strong correlation between the distorted waveform of the EPdM and the EP transport to the edge. The waveform distortion is composed of higher harmonics (n ⩾ 2) and looks like a density snake near the plasma edge. According to statistical analyses, ELM triggering by the EPdMs requires a finite level of waveform distortion and pedestal recovery. ELM pacing by the EPdMs occurs when the repetition frequency of the EPdMs is higher than the natural ELM frequency. EPs transported by EPdMs are thought to contribute to change the edge stability.

  5. Production and accumulation of 4-O-methyl-α-D-glucuronosyl-xylotriose by growing culture of thermophilic Anoxybacillus sp. strain JT-12.

    PubMed

    Thitikorn-amorn, Jitladda; Kyu, Khin Lay; Sakka, Kazuo; Ratanakhanokchai, Khanok

    2012-04-01

    A thermophilic Anoxybacillus sp. strain JT-12, isolated from soil, produced acidic xylotriose, 4-O-methyl-α-D-glucuronosyl-xylotriose (MeGlcAX₃), as a main product from birchwood xylan and accumulated them in the culture under optimum conditions at pH 7.0 and 55 °C using 0.75% (w/v) birchwood xylan as a carbon source for 42-72 h. The acidic xylotriose was purified by ethanol precipitation and high-performance liquid chromatography using NH₂ Lichosher® 100 column. The results of electrospray ionization mass spectrometry, mass to charge ratio (m/z) 603.23, confirmed that the purified sample was acidic xylotriose that had benefits and applications in many fields. PMID:22350872

  6. DC-9/JT8D refan, Phase 1. [technical and economic feasibility of retrofitting DC-9 aircraft with refan engine to achieve desired acoustic levels

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Analyses and design studies were conducted on the technical and economic feasibility of installing the JT8D-109 refan engine on the DC-9 aircraft. Design criteria included minimum change to the airframe to achieve desired acoustic levels. Several acoustic configurations were studied with two selected for detailed investigations. The minimum selected acoustic treatment configuration results in an estimated aircraft weight increase of 608 kg (1,342 lb) and the maximum selected acoustic treatment configuration results in an estimated aircraft weight increase of 809 kg (1,784 lb). The range loss for the minimum and maximum selected acoustic treatment configurations based on long range cruise at 10 668 m (35,000 ft) altitude with a typical payload of 6 804 kg (15,000 lb) amounts to 54 km (86 n. mi.) respectively. Estimated reduction in EPNL's for minimum selected treatment show 8 EPNdB at approach, 12 EPNdB for takeoff with power cutback, 15 EPNdB for takeoff without power cutback and 12 EPNdB for sideline using FAR Part 36. Little difference was estimated in EPNL between minimum and maximum treatments due to reduced performance of maximum treatment. No major technical problems were encountered in the study. The refan concept for the DC-9 appears technically feasible and economically viable at approximately $1,000,000 per airplane. An additional study of the installation of JT3D-9 refan engine on the DC-8-50/61 and DC-8-62/63 aircraft is included. Three levels of acoustic treatment were suggested for DC-8-50/61 and two levels for DC-8-62/63. Results indicate the DC-8 technically can be retrofitted with refan engines for approximately $2,500,000 per airplane.

  7. Off-axis Fishbone-like Instability and Excitation of the Resistive Wall Mode (RWM) in JT-60U and DIII-D Devices

    NASA Astrophysics Data System (ADS)

    Okabayashi, M.

    2010-11-01

    Advanced tokamak experiments in JT-60U [1] and DIII-D [2] have revealed that in high-beta q(0)>1 plasmas, where the resistive wall modes (RWMs) are predicted to be stable by kinetic effects of energetic particles, plasma rotation and a nearby conducting wall, off-axis fishbone-like instabilities often trigger RWMs. The rapid growth of these RWMs prevents high performance operation. The off-axis fishbone-like instability has some similarities to the classic m/n=1/1 internal fishbone instability in terms of its initial frequency near the energetic ion precession frequency, downward frequency-chirping, and a neutron rate drop of ˜20% during each burst. However, there are several unique non-ideal-MHD features in the off-axis fishbone-like instability. The waveform time behavior has strong non-sinusoidal distortion from the q˜2 area to the edge, synchronized with bursting energetic particle losses, while the plasma rotation is rapidly reduced within a few milliseconds. Based on experimental observations the following hypothesis emerges. In plasmas where rotation and kinetic effects are usually sufficient to stabilize the RWM, energetic particles can drive the fishbone instability of several kHz (larger than the inverse of the resistive wall time constant). The reduction of kinetic stabilization due to the resulting energetic particle loss and rapid decrease of plasma rotation makes the plasma more vulnerable to the near-zero frequency RWM. The impact on RWM stability by the off-axis fishbone with its radial and toroidal distortion of the mode structure is assessed by comparing the JT-60U/DIII-D results with theoretical predictions. 6pt [1] G. Matsunaga et al., Phys. Rev. Lett. 103, 045001. (2009). [2] M. Okabayashi et al., Nucl. Fusion 49 (2009) 125003.

  8. The influence of inlet design on the aeroacoustic performance of a JT15D turbofan engine as measured in the NASA-Ames 40 x 80 foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Holm, R. G.; Karchmer, A.; Horne, C.; Atencio, A.

    1983-01-01

    The influence of inlet design on the aeroacoustic performance of a JT15D turbofan engine was investigated in the NASA-Ames 40 x 80 ft wind tunnel. Four inlet designs representative of those found in commercial service were evaluated at a forward velocity of 80 kn. The inlet designs considered were selected to evaluate the importance of circumferential static pressure distortion (SPD) for a diffusing sound suppressing inlet and throat Mach number (Mth) for a hardwall inlet on the acoustic characteristics of the JT15D engine. Several speed points were studied simulating the operating conditions spanning approach to take-off. Results demonstrated that the dependency of the forward radiated noise on inlet aerodynamic design parameters was significant (about 5 dB) for the range of SPD (0.1-3.0%) and Mth (0.3-0.6) tested. The performance of the bulk absorber acoustic treatment used in the diffusing sound suppressing inlet is also discussed.

  9. Flight effects on noise generated by the JT8D-17 engine in a quiet nacelle and a conventional nacelle as measured in the NASA-Ames 40- by 80-foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Strout, F. G.

    1976-01-01

    A JT8D-17 turbofan engine was tested in the NASA-Ames 40- by 80-foot wind tunnel to determine flight effects on jet and fan noise. Baseline, quiet nacelle with 20-lobe ejector/suppressor, and internal mixer configurations were tested over a range of engine power settings and tunnel velocities. Flight effects derived from the 40- by 80-foot wind tunnel test are compared with 727/JT8D flight test data and with model data obtained in a smaller wind tunnel. Procedures are defined for measuring noise data in a wind tunnel relatively near the sources and analyzing the results to obtain far-field flight effects. Wind tunnel and 727 flight test noise results compare favorably for both the baseline and quiet nacelle configurations. Two reports are provided, including a comprehensive version with extensive test results and analysis and the subject summary version that emphasizes data analysis and program finding.

  10. Gyrotron development for high-power, long-pulse electron cyclotron heating and current drive at two frequencies in JT-60SA and its extension toward operation at three frequencies

    NASA Astrophysics Data System (ADS)

    Kobayashi, T.; Yokokura, S. Moriyama K.; Sawahata, M.; Terakado, M.; Hiranai, S.; Wada, K.; Sato, Y.; Hinata, J.; Hoshino, K.; Isamaya, A.; Oda, Y.; Ikeda, R.; Takahashi, K.; Sakamoto, K.

    2015-06-01

    A gyrotron enabling high-power, long-pulse oscillations at both 110 and 138 GHz has been developed for electron cyclotron heating (ECH) and current drive (CD) in JT-60SA. Oscillations of 1 MW for 100 s have been demonstrated at both frequencies, for the first time in the world as a gyrotron operating at two frequencies. The optimization of the anode voltage, or the electron pitch factor, using a triode gun was a key to obtain high power and high efficiency at two frequencies. It was also confirmed that the internal losses in the gyrotron were sufficiently low for expected long pulse operation at the higher power level of ∼1.5 MW. Another important result is that an oscillation at 82 GHz, which enables use of fundamental harmonic waves in JT-60SA while the other two frequencies are used as second harmonics waves, was demonstrated up to 0.4 MW for 2 s. These results of the gyrotron development significantly contribute to enhancing the operation regime of the ECH/CD system in JT-60SA.

  11. Flight effects on noise by the JT8D engine with inverted primary/fan flow as measured in the NASA-Ames 40 by 80 foot wind tunnel

    NASA Technical Reports Server (NTRS)

    Strout, F. G.

    1978-01-01

    A JT8D-17R engine with inverted primary and fan flows was tested under static conditions as well as in the NASA Ames 40 by 80 Foot Wind Tunnel to determine static and flight noise characteristics, and flow profile of a large scale engine. Test and analysis techniques developed by a previous model and JT8D engine test program were used to determine the in-flight noise. The engine with inverted flow was tested with a conical nozzle and with a plug nozzle, 20 lobe nozzle, and an acoustic shield. Wind tunnel results show that forward velocity causes significant reduction in peak PNL suppression relative to uninverted flow. The loss of EPNL suppression is relatively modest. The in-flight peak PNL suppression of the inverter with conical nozzle was 2.5 PNdb relative to a static value of 5.5 PNdb. The corresponding EPNL suppression was 4.0 EPNdb for flight and 5.0 EPNdb for static operation. The highest in-flight EPNL suppression was 7.5 EPNdb obtained by the inverter with 20 lobe nozzle and acoustic shield. When compared with the JT8D engine with internal mixer, the inverted flow configuration provides more EPNL suppression under both static and flight conditions.

  12. Development of a high-brightness and low-divergence lithium neutral beam for a Zeeman polarimetry on JT-60U.

    PubMed

    Kojima, Atshushi; Kamiya, Kensaku; Iguchi, Harukazu; Fujita, Takaaki; Kakiuchi, Hideto; Kamada, Yutaka

    2008-09-01

    A high-brightness and low-divergence neutral beam is obtained for a Zeeman polarimetry of edge plasmas on JT-60U. The electron density and the pitch angle of the magnetic field line, thus the plasma current density distribution, can be measured by the Zeeman polarimetry using the lithium beam. A thermionic ion source heated by an electron beam is developed in order to obtain the ion beam current extraction over 10 mA. The beam optics is designed after detailed numerical simulation taking the space charge effects into account because a low-divergence angle of the neutral lithium beam leads to a narrow spectrum of the beam emission. It is also necessary to keep the beam radius small for good spatial resolution due to a long beam line of 6.5 m. The newly developed ion gun is operated on a test stand which simulates the diagnostic arrangement on JT-60U. The ion beam current of 10 mA at a beam energy of 10 keV is successfully extracted from the ion source operated at the temperature over 1300 degrees C and focused by Einzel lens. The full width at half maximum radius of the ion beam at the neutralizer is about 9 mm. A sodium vapor neutralizer neutralizes the collimated ion beam fully at the temperature of 300 degrees C. The neutral beam profiles are measured at two locations of the beam line at Z=2.3 m (beam monitor position) and Z=6.5 m (plasma region). The half-width at half maximum radius of the neutral beam of 26 mm and the equivalent beam current of 3 mA with the beam divergence angle of 0.2 deg which is the half-angle divergence are obtained. Those parameters satisfy the requirements of the Zeeman polarimetry. Furthermore, a long pulse extraction with a current of 10 mA and duration of 50 s is attained. PMID:19044408

  13. Phase 2 program on ground test of refanned JT8D turbofan engines and nacelles for the 727 airplane. Volume 4: Airplane evaluation and analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The retrofit of JT8D-109 (refan) engines are evaluated on a 727-200 airplane in terms of airworthiness, performance, and noise. Design of certifiable hardware, manufacture, and ground testing of the essential nacelle components is included along with analysis of the certifiable airplane design to ensure airworthiness compliance and to predict the in-flight performance and noise characteristics of the modified airplane. The analyses confirm that the 727 refan airplane is certifiable. The refan airplane range would be 15% less that of the baseline airplane and block fuel would be increased by 1.5% to 3%. However, with this particular 727-200 model, with a brake release gross weight of 172,500 lb (78,245 kg), it is possible to operate the airplane (with minor structural modifications) at higher gross weights and increase the range up to 15% over the 727-200 (baseline) airplane. The refan airplane FAR Part 36 noise levels would be 6 to 8 EPNdB (effective perceived noise in decibels) below the baseline. Noise footprint studies showed that approach noise contour areas are small compared to takeoff areas. The 727 refan realizes a 68% to 83% reduction in annoyance-weighted area when compared to the 727-200 over a range of gross weights and operational procedures.

  14. Approach to a window coating problem by {ital in situ} transmission monitoring and laser blow-off cleaning developed in the JT-60U Thomson scattering system

    SciTech Connect

    Yoshida, H.; Naito, O.; Hatae, T.; Nagashima, A.

    1997-01-01

    For solving a window coating problem, an {ital in situ} window transmission monitoring by inferring it precisely from a known attenuation of the deposited film has been developed in the JT-60U Thomson scattering system. Also the practicability of an {ital in situ} window cleaning based on a laser blow-off technique has been investigated extensively. The coated film composition could be guessed to be a resin such as {ital polyacrylonitrile} with a small amount of metals. The existence of chromatic upper limit has been found in the recovered transmission after the blow-off cleaning, which gives systematic errors only of less than 3% to an apparent measurement of both electron density and temperature at 10 keV or less. The attenuation itself is unchanged before and after the laser blow-off cleaning. A complementary use of both methods will provide the Thomson scattering measurement of high T{sub e} plasmas with durable reliability and sufficient precision in the existing tokamaks and the International Thermonuclear Experimental Reactor. {copyright} {ital 1997 American Institute of Physics.}

  15. Thermal-hydraulic analysis of transients in the HELIOS loop including a CICC section representative of the JT-60SA Central Solenoid

    NASA Astrophysics Data System (ADS)

    Carli, S.; Bonifetto, R.; Hoa, C.; Savoldi, L.; Zanino, R.

    2015-12-01

    The HELIOS facility at CEA Grenoble is a supercritical helium (SHe) loop which is being used to investigate the effects on the cryogenic cooling system of the pulsed heat loads which are typical of superconducting tokamak operation. In the standard configuration, the magnet heat load is simulated by electrical heaters wrapped around a section of cryoline. In the present work, the resistively heated section is substituted in the HELIOS model of the 4C code, already validated for the standard configuration of HELIOS, by a sub-size winding structure made of JT-60SA Cable-In-Conduit Conductors (CICCs). The new model is then used to highlight the differences in the circuit behaviour when the heated pipe is substituted by an actual magnet wound with CICCs, checking the representativeness of the control strategies developed for the present HELIOS configuration. The use of CICCs will be shown to produce an intrinsic smoothing of the temperature profiles which is not affecting the capability of the control strategies to smooth the heat loads to the cryoplant.

  16. The results of low-speed wind tunnel tests to investigate the effects of the NASA refan JT8D engine nacelles on the stability and control characteristics of the Boeing 727-200

    NASA Technical Reports Server (NTRS)

    Shirkey, M. D.

    1973-01-01

    The results from two low-speed wind tunnel tests of the Boeing 727-200 airplane as configured with the NASA refan JT8D-109 turbofan engines are presented. The objective of these tests was to determine the effects of the refan installation on the low-speed stability and control characteristics of the 727 airplane. Four side nacelle locations were tested to insure that aerodynamic interactions of the nacelles and empennage would be optimized. The optimum location was judged to be the same as that of the production JT8D-9 engines; the current production engine mounts can be used for this location. Some small changes in the basic airplane characteristics are attributable to the refan nacelles. The flaps up longitudinal and lateral-directional stability are both slightly increased for low angles of attack and sideslip respectively. The longitudinal stability at stall is improved for both the flaps up and landing flap configurations. The high attitude characteristics of the basic airplane are not significantly altered by the refan nacelle installation. Directional control capability is not affected by the refan nacelles.

  17. Recent RF Experiments and Application of RF Waves to Real-Time Control of Safety Factor Profile in JT-60U

    SciTech Connect

    Suzuki, T.; Isayama, A.; Ide, S.; Fujita, T.; Oikawa, T.; Sakata, S.; Sueoka, M.; Hosoyama, H.; Seki, M.

    2005-09-26

    Two topics of applications of RF waves to current profile control in JT-60U are presented; application of lower-hybrid (LH) waves to safety factor profile control and electron cyclotron (EC) waves to neo-classical tearing mode (NTM) control. A real-time control system of safety factor (q) profile was developed. This system, for the first time, enables 1) real time evaluation of q profile using local magnetic pitch angle measurement by motional Stark effect (MSE) diagnostic and 2) control of current drive (CD) location ({rho}CD) by controlling the parallel refractive index N parallel of LH waves through control of phase difference ({delta}{phi}) of LH waves between multi-junction launcher modules. The method for real-time q profile evaluation was newly developed, without time-consuming reconstruction of equilibrium, so that the method requires less computational time. Safety factor profile by the real-time calculation agrees well with that by equilibrium reconstruction with MSE. The control system controls {rho}CD through {delta}{phi} in such a way to decrease the largest residual between the real-time evaluated q profile q(r) and its reference profile qref(r). The real-time control system was applied to a positive shear plasma (q(0){approx}1). The reference q profile was set to monotonic positive shear profile having qref(0)=1.3. The real-time q profile approached to the qref(r) during application of real-time control, and was sustained for 3s, which was limited by the duration of the injected LH power. Temporal evolution of current profile was consistent with relaxation of inductive electric field induced by theoretical LH driven current. An m/n=3/2 NTM that appeared at {beta}N{approx}3 was completely stabilized by ECCD applied to a fully-developed NTM. Precise ECCD at NTM island was essential for the stabilization. ECCD that was applied to resonant rational surface (q=3/2) before an NTM onset suppressed appearance of NTM. In order to keep NTM intensity below a level, ECCD before the mode onset was more effective than that after mode saturation.

  18. Recent RF Experiments and Application of RF Waves to Real-Time Control of Safety Factor Profile in JT-60U

    NASA Astrophysics Data System (ADS)

    Suzuki, T.; Isayama, A.; Ide, S.; Fujita, T.; Oikawa, T.; Sakata, S.; Sueoka, M.; Hosoyama, H.; JT-60 Team

    2005-09-01

    Two topics of applications of RF waves to current profile control in JT-60U are presented; application of lower-hybrid (LH) waves to safety factor profile control and electron cyclotron (EC) waves to neo-classical tearing mode (NTM) control. A real-time control system of safety factor (q) profile was developed. This system, for the first time, enables 1) real time evaluation of q profile using local magnetic pitch angle measurement by motional Stark effect (MSE) diagnostic and 2) control of current drive (CD) location (ρCD) by controlling the parallel refractive index N∥ of LH waves through control of phase difference (Δφ) of LH waves between multi-junction launcher modules. The method for real-time q profile evaluation was newly developed, without time-consuming reconstruction of equilibrium, so that the method requires less computational time. Safety factor profile by the real-time calculation agrees well with that by equilibrium reconstruction with MSE. The control system controls ρCD through Δφ in such a way to decrease the largest residual between the real-time evaluated q profile q(r) and its reference profile qref(r). The real-time control system was applied to a positive shear plasma (q(0)˜1). The reference q profile was set to monotonic positive shear profile having qref(0)=1.3. The real-time q profile approached to the qref(r) during application of real-time control, and was sustained for 3s, which was limited by the duration of the injected LH power. Temporal evolution of current profile was consistent with relaxation of inductive electric field induced by theoretical LH driven current. An m/n=3/2 NTM that appeared at βN˜3 was completely stabilized by ECCD applied to a fully-developed NTM. Precise ECCD at NTM island was essential for the stabilization. ECCD that was applied to resonant rational surface (q=3/2) before an NTM onset suppressed appearance of NTM. In order to keep NTM intensity below a level, ECCD before the mode onset was more effective than that after mode saturation.

  19. Boundary condition for toroidal plasma flow imposed at the separatrix in high confinement JT-60U plasmas with edge localized modes and the physics process in pedestal structure formation

    SciTech Connect

    Kamiya, K.; Honda, M.; Urano, H.; Yoshida, M.; Kamada, Y.; Itoh, K.

    2014-12-15

    Modulation charge eXchange recombination spectroscopy measurements with high spatial and temporal resolution have made the evaluation of the toroidal plasma flow of fully stripped carbon impurity ions (V{sub ϕ}{sup C6+}) in the JT-60U tokamak peripheral region (including, in particular, the separatrix) possible with a better signal-to-noise ratio. By comparing co- and counter-neutral beam injection discharges experimentally, we have identified the boundary condition of V{sub ϕ}{sup C6+} and radial electric field shear (∇E{sub r}) imposed at the separatrix in high confinement (H-mode) plasmas with edge localized modes (ELMs). The V{sub ϕ}{sup C6+} value at the separatrix is not fixed at zero but varies with the momentum input direction. On the other hand, the ∇E{sub r} value is nearly zero (or very weakly positive) at the separatrix. Furthermore, the edge localized mode perturbation does not appear to affect both V{sub ϕ}{sup C6+} and ∇E{sub r} values at the separatrix as strongly as that in the pedestal region. The above experimental findings based on the precise edge measurements have been used to validate a theoretical model and develop a new empirical model. A better understanding of the physical process in the edge transport barrier (ETB) formation due to the sheared E{sub r} formation is also discussed.

  20. The results of a low speed wind tunnel test to investigate the effects of installing refan JT8D engines on the McDonnell Douglas DC-9-30

    NASA Technical Reports Server (NTRS)

    Chrisenberry, H. E.; Doss, P. G.; Kressly, A. E.; Prichard, R. D.; Thorndike, C. S.

    1973-01-01

    A low speed wind tunnel test was conducted to assess the effects of the larger JT8D refan nacelles on the stability and control characteristics of the DC-9-30, with emphasis on the deep stall regime. Deep stall pitching moment and elevator hinge moment data, and low angle of attack tail-on and tail-off pitching moment data are presented. The refan nacelle was tested in conjunction with various pylons of reduced span relative to the production DC-9-30 pylon. Also, a horizontal tail that was larger than the production tail was tested. The data show that the refan installation has a small detrimental effect on the DC-9-30 deep stall recovery capability, that recovery characteristics are essentially independent of pylon span, and that the larger horizontal tail significantly increases recovery margins. The deep stall characteristics with the refan installation, within the range of pylon spans tested, are acceptable with no additional design changes anticipated.

  1. JT/LJT connector insert material evaluation

    SciTech Connect

    Baca, J.R.F.

    1991-10-01

    Different insert (insulator) materials are undergoing evaluation to replace the Fiberite E-3938 BE96 material currently used. Also being evaluated is the reconfiguration of the insert and metal shell-edge geometries for the purpose of reducing the alleged interference principally responsible for insert damage.

  2. JT90 thermal barrier coated vanes

    NASA Technical Reports Server (NTRS)

    Sheffler, K. D.; Graziani, R. A.; Sinko, G. C.

    1982-01-01

    The technology of plasma sprayed thermal barrier coatings applied to turbine vane platforms in modern high temperature commercial engines was advanced to the point of demonstrated feasibility for application to commercial aircraft engines. The three thermal barrier coatings refined under this program are zirconia stabilized with twenty-one percent magnesia (21% MSZ), six percent yttria (6% YSZ), and twenty percent yttria (20% YSZ). Improvement in thermal cyclic endurance by a factor of 40 times was demonstrated in rig tests. A cooling system evolved during the program which featured air impingement cooling for the vane platforms rather than film cooling. The impingement cooling system, in combination with the thermal barrier coatings, reduced platform cooling air requirements by 44% relative to the current film cooling system. Improved durability and reduced cooling air requirements were demonstrated in rig and engine endurance tests. Two engine tests were conducted, one of 1000 cycles and the other of 1500 cycles. All three coatings applied to vanes fabricated with the final cooling system configuration completed the final 1500 cycle engine endurance test. Results of this test clearly demonstrated the durability of the 6% YSZ coating which was in very good condition after the test. The 21% MSZ and 20% YSZ coatings had numerous occurrences of significant spalling in the test.

  3. Miniature J-T refrigators using adsorption compressors

    NASA Technical Reports Server (NTRS)

    Chan, C. K.; Tward, E.; Elleman, D. D.

    1982-01-01

    More sophisticated cooling systems for the employed detectors will be needed to satisfy the demand for higher resolution and sensitivity of various detectors used in space missions. The design of the cooling system must take into consideration the unique environment of space vehicles. It is pointed out that a deep space vehicle usually has an ample supply of waste heat from a radioisotope thermoelectric generator (RTG) and has a heat sink near zero Kelvin. Passive radiative coolers have been used for cooling temperatures above 90 K. Cooling below 90 K is currently handled by phase changes of solid or liquid cryogens or mechanical refrigeration. However, the weight of the cryogen may be a problem in a long duration space mission. Refrigerators of small cooling capacity are required in many spacecraft applications. For some future NASA missions, a multistage Joule-Thomson refrigerator using adsorption compressors appears particularly attractive. A study is discussed of four different refrigeration stages which use charcoal as the adsorbent. The adsorbed gases are nitrogen, helium, hydrogen, and neon.

  4. Clean-up of graphite first walls in JT-60

    NASA Astrophysics Data System (ADS)

    Arai, T.; Takatsu, H.; Ninomiya, H.; Yoshino, R.; Hosogane, N.; Yamamoto, M.; Kodama, K.; Kaminaga, A.; Shimizu, M.; JT-60 Team

    1989-04-01

    During the venting period from April to May 1987 about a half of TiC-coated molybdenum and Inconel 625 first walls were removed and graphite first walls were installed. The overall surface area and the weight of the graphite tiles are 200 m 2 and 3500 kg, respectively. Two kinds of isotropic graphite (Ibiden ETP-10 and Hitachi-Chemical HCB-18S) were used. Special attention was paid to the contamination of the graphite first walls during the courses of fabrication and installation. Main discharge were tried after 7 d conditioning, which included 3 d bakeout at the temperature of 300°C, 18 h glow discharge cleaning and 36 h Taylor-type discharge cleaning keeping the vessel temperature around 280°C. A 0.5 MA stable plasma was successfully attained at the 6th shot and a very rapid start-up of the discharge conditioning with plasma current up to 1 MA was achieved with 14 shots. An ultimate pressure of 6.4 × 10 -7 Pa was obtained with the vessel temperature at RT and the residual gases were water, carbon oxide and carbon hydride.

  5. Sorption J-T refrigeration utilizing manganese nitride chemisorption

    NASA Technical Reports Server (NTRS)

    Jones, Jack; Lund, Alan

    1990-01-01

    The equilibrium pressures and compositions have been measured for a system of finely powdered manganese nitride and nitrogen gas at 650, 700, 800, and 850 C for various nitrogen loadings. Pressures ranged from less than 0.02 MPa at 650 C to 6.38 MPa at 850 C. Analysis of the test results has shown that under certain conditions Mn(x)N(y) could potentially be used in a triple regenerative sorption compressor refrigeration system, but the potential power savings are small compared to the increased complexity and reliability problems associated with very high temperature (above 950 C) pressurized systems.

  6. Predicting Mothers' Reports of Children's Mental Health Three Years after Hurricane Katrin.

    PubMed

    Lowe, Sarah R; Godoy, Leandra; Rhodes, Jean E; Carter, Alice S

    2013-01-01

    This study explored pathways through which hurricane-related stressors affected the psychological functioning of elementary school aged children who survived Hurricane Katrina. Participants included 184 mothers from the New Orleans area who completed assessments one year pre-disaster (Time 1), and one and three years post-disaster (Time 2 and Time 3, respectively). Mothers rated their children's behavior problems at Time 3 only (n = 251 children; 53.0% male; Mean age: 10.19 years, SD = 1.68 years). A path analytic model indicated that hurricane-related stressors were associated with increased maternal psychological distress and school mobility in the first post-disaster year, which were associated with higher child internalizing and externalizing symptoms three years post-disaster. Mediation analysis indicated that hurricane-related stressors were associated with child symptoms indirectly, through their impact on maternal psychological distress. Findings underscore the importance of interventions that boost maternal and child mental health and support children through post-disaster school transitions. PMID:23471125

  7. Predicting Mothers’ Reports of Children’s Mental Health Three Years after Hurricane Katrin

    PubMed Central

    Lowe, Sarah R.; Godoy, Leandra; Rhodes, Jean E.; Carter, Alice S.

    2012-01-01

    This study explored pathways through which hurricane-related stressors affected the psychological functioning of elementary school aged children who survived Hurricane Katrina. Participants included 184 mothers from the New Orleans area who completed assessments one year pre-disaster (Time 1), and one and three years post-disaster (Time 2 and Time 3, respectively). Mothers rated their children’s behavior problems at Time 3 only (n = 251 children; 53.0% male; Mean age: 10.19 years, SD = 1.68 years). A path analytic model indicated that hurricane-related stressors were associated with increased maternal psychological distress and school mobility in the first post-disaster year, which were associated with higher child internalizing and externalizing symptoms three years post-disaster. Mediation analysis indicated that hurricane-related stressors were associated with child symptoms indirectly, through their impact on maternal psychological distress. Findings underscore the importance of interventions that boost maternal and child mental health and support children through post-disaster school transitions. PMID:23471125

  8. 76 FR 72130 - Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    .... Discussion On March 1, 2007, we issued AD 2007-05-17, Amendment 39-14978 (72 FR 10350, March 8, 2007), for... result in an uncontained engine failure and damage to the airplane. Actions Since Existing AD (72 FR... requirements of AD 2007- 05-17 (72 FR 10350, March 8, 2007). This proposed AD would supersede AD 2007-05-17...

  9. Effect of steady flight loads on JT9D-7 performance deterioration

    NASA Technical Reports Server (NTRS)

    Jay, A.; Todd, E. S.

    1978-01-01

    Short term engine deterioration occurs in less than 250 flights on a new engine and in the first flights following engine repair; while long term deterioration involves primarily hot section distress and compression system losses which occur at a somewhat slower rate. The causes for short-term deterioration are associated with clearance changes which occur in the flight environment. Analytical techniques utilized to examine the effects of flight loads and engine operating conditions on performance deterioration are presented. The role of gyroscopic, gravitational, and aerodynamic loads are discussed along with the effect of variations in engine build clearances. These analytical results are compared to engine test data along with the correlation between analytically predicted and measured clearances and rub patterns. Conclusions are drawn and important issues are discussed.

  10. Performance deterioration based on simulated aerodynamic loads test, JT9D jet engine diagnostics program

    NASA Technical Reports Server (NTRS)

    Stromberg, W. J.

    1981-01-01

    An engine was specially prepared with extensive instrumentation to monitor performance, case temperatures, and clearance changes. A special loading device was used to apply known loads on the engine by the use of cables placed around the flight inlet. These loads simulated the estimated aerodynamic pressure distributions that occur on the inlet in various segments of a typical airplane flight. Test results indicate that the engine lost 1.3 percent in take-off thrust specific fuel consumption (TSFC) during the course of the test effort. Permanent clearance changes due to the loads accounted for 1.1 percent; increase in low pressure compressor airfoil roughness and thermal distortion in the high pressure turbine accounted for 0.2 percent. Pretest predicted performance loss due to clearance changes was 0.9 percent in TSFC. Therefore, the agreement between measurement and prediction is considered to be excellent.

  11. DEVELOPMENT OF A LOW HEAT LEAK CFRP STAND FOR MIRI COOLER JT HEAT EXCHANGER STAGE

    SciTech Connect

    Makowski, K. P.; Hayashil, B.; Larson, M. E.; Loc, A. S.; Zhang, B. X.; Leland, R. S.

    2010-04-09

    A low heat leak stand is being developed for the Heat exchanger Stage Assembly (HSA) of the cryocooler subsystem for the Mid Infra-Red Instrument (MIRI) of the James Webb Space Telescope (JWST). The HSA stand is a hexapod structure supporting the 18 K HSA in a nominal 40 K background environment. Carbon fiber reinforced plastic (CFRP) has been selected for this application to meet the stringent design requirements of a low parasitic heat leak (less than 3.8 mW including both conductive and radiative heat loads for the thermal environment defined above) and a resonance frequency above 120 Hz. A directional lay-up of T300/polycyanate has been chosen for the construction of the hexapod struts. End fittings made of Invar 36 are bonded to the struts to provide structural interfaces. The development effort includes fabricating and testing (including cryogenic thermal cycling) six types of coupons for material characterization, determination of structural degradation due to thermal cycling, and selection of the joint bonding epoxy. Consequently, strut samples are used for final material characterization, performance assessment, and bond joint design evaluation. This paper describes the development process and addresses the challenges in meeting the design requirements. Results of finite element analysis (FEA) for the composite structure and experimental data collected through structural and thermal testing are also presented.

  12. Performance evaluation of heat exchanger for mixed refrigerant J-T cryocooler

    NASA Astrophysics Data System (ADS)

    Ardhapurkar, P. M.; Sridharan, Arunkumar; Atrey, M. D.

    2014-09-01

    In mixed refrigerant Joule-Thomson cryocooler, a multi-component mixture of nitrogen-hydrocarbons undergoes evaporation and condensation process in a helical coiled heat exchanger simultaneously at different pressures. Experimental data and empirical correlations for predicting heat transfer coefficients of evaporating and condensing streams of multi-component mixtures at cryogenic temperatures are unavailable. As a result, design of these heat exchangers is a challenging task. The present work aims to address this challenge. It assesses the existing condensation correlations against the calculated data obtained during experimentation. Experiments are conducted to determine overall heat transfer coefficients along the length of the heat exchanger for various mixtures. The paper studies the applicability of these correlations to the multi-component mixtures at cryogenic temperatures.

  13. DC-9 flight demonstration program with refanned JT8D engines. Volume 2: Design and construction

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The nacelle configuration selected for the DC-9 had a 1595.6 mm Refan length inlet and an 1811.8 mm exhaust duct. The inlet had 1234.4 mm of acoustic treatment and the tailpipe had 1305.5 mm of equivalent length acoustic treatment. The pylon was reduced in width from 425.5 mm to 204.5 mm. Fuselage frames and titanium skin panels in the area of the pylon were reinforced or replaced to support the higher loads and engine thrust. Experimental type tooling, fabrication and assembly were used on all hardware. The design is considered certifiable and representative of the hardware that would be built as retrofit kits.

  14. Development of a low-noise 10K J-T refrigeration system. Technical progress report

    SciTech Connect

    Little, W.A.; Edman, H.; Stewart, M.; DuBois, M.; Nasg, A.

    1986-08-15

    This report summarizes the work done to date, in the first 30 days on the development of a low-noise, Joule-Thomson, microminiature refrigeration system designed for 10K operation. The plan of attack for the present contract has three major parts to it: first, the development of the three-stage refrigerator; second, the development of a suitable compressor to provide the gases, and thirdly, the development of an effective gas-cleansing system.

  15. Development of a low-noise 10 K J-T refrigeration system. Technical progress report

    SciTech Connect

    Paugh, R.L.

    1989-09-15

    The purpose of this contract extension is the continuation of the development of a compact, microminiature, low-noise, closed-cycle, Joule-Thomson refrigeration system for 10K operation for use in infrared sensing, low noise microwave signal detection and high speed superconducting electronic data processing. Work is continuing in the following areas: (a) Ongoing refrigerator design and development; (b) Compressor assembly and test, (c) Implementation of gas cleansing techniques, and (d) System integration.

  16. Comparison of Ne and Ar seeded radiative divertor plasmas in JT-60U

    NASA Astrophysics Data System (ADS)

    Nakano, T.

    2015-08-01

    In H-mode plasmas with Ne, Ar and a mixture of Ne and Ar injection, the divertor radiation power fractions amongst these impurities in addition to an intrinsic impurity, C, are investigated. In plasmas with the inner divertor plasma attached, carbon is the biggest radiator, whichever impurity, Ne, Ar or a mixture of Ar and Ne is injected. In contrast, in plasmas with the inner divertor plasma detached, Ne is the biggest radiator due to a significantly high recombination radiation from Ne VIII. Ar is always a minor contributor in plasmas with the inner divertor both attached and detached.

  17. Development of a hermetically sealed brushless DC motor for a J-T cryocooler

    NASA Technical Reports Server (NTRS)

    Joscelyn, Edwin; Hochler, Irwin; Ferri, Andrew; Rott, Heinz; Soukaris, Ted

    1996-01-01

    This development was sponsored by Ball Aerospace for the Cryogenic On-Orbit LongLife Active Refrigerator (COOLLAR) program. The cryocooler is designed to cool objects to 65 K and operate in space for at least 7 years. The system also imports minimal impact to the spacecraft in terms of vibration and heat. The basic Joule-Thompson cycle involves compressing a working fluid, nitrogen in this case, at near-constant temperature from 17.2 KPa to 6.89 MPa. The nitrogen is then expanded through a Joule-Thompson valve. The pure nitrogen gas must be kept clean; therefore, any contamination from motor organic materials must be eliminated. This requirement drove the design towards sealing of the motor within a titanium housing without sacrificing motor performance. It is estimated that an unsealed motor would have contributed 1.65 g of contaminants, due to the organic insulation and potting materials, over the 7-year life. This paper describes the motor electrical and mechanical design, as well as the sealing difficulties encountered, along with their solutions.

  18. Control of Growth of Neoclassical Tearing Mode by Central Co-ECCD in JT-60U

    NASA Astrophysics Data System (ADS)

    Isayama, Akihiko; Oyama, Naoyuki; Urano, Hajime; Suzuki, Takahiro; Takechi, Manabu; Ide, Shunsuke; Kamada, Yutaka; Ozeki, Takahisa; Nagasaki, Kazunobu; JT-60 Team, Kazunobu

    Growth of a neoclassical tearing mode (NTM) with a poloidal mode number m = 3 and a toroidal mode number n = 2 has been controlled by electron cyclotron current drive (ECCD) in the same direction as the plasma current (co-ECCD) in the central region away from the NTM island. By using ECCD at a fraction of about 10% of the plasma current, the amplitude of the m/n = 3/2 NTM is limited to about 1/5 of that without ECCD. The frequency spectrum of magnetic perturbations shows that the frequency of the m/n = 3/2 NTM is modulated by a sawtooth crash. The beta value, which is the ratio of the plasma pressure to the magnetic pressure, is higher by 6% than that without ECCD at the same input power. This operational scenario is quite different from that for conventional NTM stabilization in which the ECCD location is accurately adjusted at the mode rational surface and is thus off-axis. This result shows the compatibility of sawtooth oscillations and a small-amplitude 3/2 NTM, and suggests the possibility of a new and easier operational scenario for NTM control.

  19. Performance characterization of a 6-K multiple JT helium adsorption cryocooler

    NASA Technical Reports Server (NTRS)

    Elliot, S.; Johnson, D. L.; Lindersmith, C. A.; Sirbi, A.

    2002-01-01

    We present the work done at the Jet Propulsion Laboratory for a Helium Adsorption Cooler to produce continuous cooling power at a temperature around 6 K. The goal of this development is to be able to propose for future space mission a long lifetime, vibration free cooler, which can cover the temperature range 18 K to 5 K.

  20. Short-term performance deterioration in JT9D-7A(SP) engine 695743

    NASA Technical Reports Server (NTRS)

    Bouchard, R. J.; Beyerly, W. R.; Sallee, G. P.

    1978-01-01

    The level of performance deterioration that occurred during early service was studied and also the contribution of each engine module to the overall level of engine performance deterioration. To assist in the distribution of the performance losses to the module level, testing with expanded experimental instrumentation was accomplished to permit direct measurement of module performance. An analytical teardown of the engine was accomplished to permit assignment of module performance losses to individual mechanical damage mechanisms including blade and seal wear, roughness, and thermal distortion of turbine parts. The results of the testing show that the engine deteriorated 1.5 percent in thrust specific fuel consumption from its performance when new. Initial testing, which included water washing, showed that 0.2 percent in performance deterioration was due to surface contamination (dirt) and 0.1 percent was due to drift of the engine vane control system, leaving 1.2 percent in basic TSFC deterioration. This 1.2 percent TSFC loss was distributed among the engine modules with 0.6 percent caused by clearance changes, 0.4 percent loss due to thermal distortion, and 0.2 percent loss due to increased roughness of the fan and low-pressure compressor airfoils.

  1. Development of a low noise 10K J-T refrigeration system. Final technical report

    SciTech Connect

    Not Available

    1986-02-01

    This report summarizes the results of an engineering design program to develop a low-noise, closed-cycle, Joule-Thomson, microminiature refrigeration system for 10K operation. During this period, the effort focused on the fabrication of the argon and hydrogen stages of the three-stage cooler. A test facility was designed and built which allows one to mount each refrigerator on a separate removable base and to test each in turn. Key to the successful fabrication of the refrigerator is the determination of the proper firing profile for sealing the refrigerator components. Three batches of refrigerators have been built to date, and reasonable yields are now being obtained for the fabrication of these stages. The helium stage has been designed and laid out, and the photomasks prepared. Work has continued on the hydraulically actuated compressor.

  2. Development of a low-noise 10 K J-T refrigeration system. Technical progress report

    SciTech Connect

    Little, W.A.

    1990-02-15

    This report summarizes work done on the development of a low noise Joule-Thomson, microminiature refrigeration system design for 10K operation. Good progress has been made on the compressor and on the waterknife to be used for the fabrication of the refrigerators. Work on the refrigerator itself is progressing well. Difficulties which had been experienced previously resulting in the warming of the nitrogen stage precooler appear to be due to inefficiency of the final stage laminar flow heat exchanger. This inefficiency is strongly dependent upon the mass flow through this stage, and difficulty in controlling this to the required precision caused the wide range of variations in the performance of otherwise similar coolers.

  3. Development of a Low Heat Leak CFRP Stand for Miri Cooler jt Heat Exchanger Stage

    NASA Astrophysics Data System (ADS)

    Makowski, K. P.; Larson, M. E.; Loc, A. S.; Zhang, B. X.; Leland, R. S.; Hayashi1, B.

    2010-04-01

    A low heat leak stand is being developed for the Heat exchanger Stage Assembly (HSA) of the cryocooler subsystem for the Mid Infra-Red Instrument (MIRI) of the James Webb Space Telescope (JWST). The HSA stand is a hexapod structure supporting the 18 K HSA in a nominal 40 K background environment. Carbon fiber reinforced plastic (CFRP) has been selected for this application to meet the stringent design requirements of a low parasitic heat leak (less than 3.8 mW including both conductive and radiative heat loads for the thermal environment defined above) and a resonance frequency above 120 Hz. A directional lay-up of T300/polycyanate has been chosen for the construction of the hexapod struts. End fittings made of Invar 36 are bonded to the struts to provide structural interfaces. The development effort includes fabricating and testing (including cryogenic thermal cycling) six types of coupons for material characterization, determination of structural degradation due to thermal cycling, and selection of the joint bonding epoxy. Consequently, strut samples are used for final material characterization, performance assessment, and bond joint design evaluation. This paper describes the development process and addresses the challenges in meeting the design requirements. Results of finite element analysis (FEA) for the composite structure and experimental data collected through structural and thermal testing are also presented.

  4. Program on ground test of modified quiet, clean, JT3D and JT8D turbofan engines in their respective nacelles. [modification of Boeing 707, 727, and 737 aircraft for aircraft noise reduction

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A program to reduce the community noise levels of commercial jet aircraft is summarized. The program objective is the development of three acoustically treated nacelle configurations for the 707, 727, and 737 series aircraft to provide maximum noise reduction with minimum performance loss, modification requirements, and economic impact. The preliminary design, model testing, data analyses, and economic studies of proposed nacelle configurations are discussed.

  5. Validation of 3D Code KATRIN For Fast Neutron Fluence Calculation of VVER-1000 Reactor Pressure Vessel by Ex-Vessel Measurements and Surveillance Specimens Results

    NASA Astrophysics Data System (ADS)

    Dzhalandinov, A.; Tsofin, V.; Kochkin, V.; Panferov, P.; Timofeev, A.; Reshetnikov, A.; Makhotin, D.; Erak, D.; Voloschenko, A.

    2016-02-01

    Usually the synthesis of two-dimensional and one-dimensional discrete ordinate calculations is used to evaluate neutron fluence on VVER-1000 reactor pressure vessel (RPV) for prognosis of radiation embrittlement. But there are some cases when this approach is not applicable. For example the latest projects of VVER-1000 have upgraded surveillance program. Containers with surveillance specimens are located on the inner surface of RPV with fast neutron flux maximum. Therefore, the synthesis approach is not suitable enough for calculation of local disturbance of neutron field in RPV inner surface behind the surveillance specimens because of their complicated and heterogeneous structure. In some cases the VVER-1000 core loading consists of fuel assemblies with different fuel height and the applicability of synthesis approach is also ambiguous for these fuel cycles. Also, the synthesis approach is not enough correct for the neutron fluence estimation at the RPV area above core top. Because of these reasons only the 3D neutron transport codes seem to be satisfactory for calculation of neutron fluence on the VVER-1000 RPV. The direct 3D calculations are also recommended by modern regulations.

  6. Low speed wind tunnel flow field results for JT8D refan engines on the Boeing 727-200

    NASA Technical Reports Server (NTRS)

    Easterbrook, W. G.; Roberts, W. H.

    1974-01-01

    Low speed flow angularity results are presented showing flow direction at the nacelle locations on the Boeing 727-200. Flow angle probes (yawheads) were used for measurements at side and center inlet positions on the aft fuselage. A range of flap settings were tested with flap angles of 0 deg, 15 deg, and 40 deg selected for investigation.

  7. 75 FR 38052 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Series Turbofan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... April 11, 2000 (65 FR 19477-78). Examining the AD Docket You may examine the AD docket on the Internet... 39 by superseding AD 2005-02- 03, Amendment 39-13948 (70 FR 3867, January 27, 2005). That AD requires... Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and 3. Would not have a...

  8. 76 FR 16526 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Series Turbofan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-24

    ...-13948 (70 FR 3867, January 27, 2005). That AD applies to the specified products. The NPRM published in the Federal Register on July 1, 2010 (75 FR 38052). That NPRM proposed the same torque inspection... 12866; (2) Is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR...

  9. Evaluation of two inflow control devices for flight simulation of fan noise using a JT15D engine

    NASA Technical Reports Server (NTRS)

    Jones, W. L.; Mcardle, J. G.; Homyak, L.

    1979-01-01

    The program was developed to accurately simulate flight fan noise on ground static test stands. The results generally indicated that both the induct and external ICD's were effective in reducing the inflow turbulence and the fan blade passing frequency tone generated by the turbulence. The external ICD was essentially transparent to the propagating fan tone but the induct ICD caused attenuation under most conditions.

  10. Off-axis current drive and real-time control of current profile in JT-60U

    NASA Astrophysics Data System (ADS)

    Suzuki, T.; Ide, S.; Oikawa, T.; Fujita, T.; Ishikawa, M.; Seki, M.; Matsunaga, G.; Hatae, T.; Naito, O.; Hamamatsu, K.; Sueoka, M.; Hosoyama, H.; Nakazato, M.; JT-60 Team

    2008-04-01

    Aiming at optimization of current profile in high-β plasmas for higher confinement and stability, a real-time control system of the minimum of the safety factor (qmin) using the off-axis current drive has been developed. The off-axis current drive can raise the safety factor in the centre and help to avoid instability that limits the performance of the plasma. The system controls the injection power of lower-hybrid waves, and hence its off-axis driven current in order to control qmin. The real-time control of qmin is demonstrated in a high-β plasma, where qmin follows the temporally changing reference qmin,ref from 1.3 to 1.7. Applying the control to another high-β discharge (βN = 1.7, βp = 1.5) with m/n = 2/1 neo-classical tearing mode (NTM), qmin was raised above 2 and the NTM was suppressed. The stored energy increased by 16% with the NTM suppressed, since the resonant rational surface was eliminated. For the future use for current profile control, current density profile for off-axis neutral beam current drive (NBCD) is for the first time measured, using the motional Stark effect diagnostic. Spatially localized NBCD profile was clearly observed at the normalized minor radius ρ of about 0.6-0.8. The location was also confirmed by multi-chordal neutron emission profile measurement. The total amount of the measured beam driven current was consistent with the theoretical calculation using the ACCOME code. The CD location in the calculation was inward shifted than the measurement.

  11. 75 FR 12968 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217C, and -219 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    ... (62 FR 4902). ADDRESSES: You can get the service information identified in this AD from Pratt... proposed AD in the Federal Register on December 21, 2009 (74 FR 67831). That action proposed to require...'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) Will not have...

  12. Analysis of radiation patterns of interaction tones generated by inlet rods in the JT15D engine

    NASA Technical Reports Server (NTRS)

    Heidmann, M. F.; Saule, A. V.

    1979-01-01

    Interaction tones were intentionally generated by circumferential arrays of equally spaced rods that protrude radially from the inlet wall near the face of the 28-blade fan. Arrays of 28 and 41 rods, selected to give specific far field radiation properties, were tested. The expected properties were readily apparent in the measured radiation patterns. A more detailed analysis of the test data showed both the precision and limitations of the applied acoustic theory. Rods protruding 23 percent of the radius predominantly generated only lowest radial order modes, as expected. Measured and predicted radiation patterns were generally in good agreement. The agreement, however, depended on a significant degree of implied refraction due to inlet velocity gradients. Refraction, if present, would impact static-flight noise comparisons.

  13. 76 FR 8620 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ...-14242 (70 FR 71610, November 29, 2005). That AD applies to the specified products. The NPRM published in the Federal Register on August 18, 2010 (75 FR 50945). That NPRM proposed to modify the TLS of the... Executive Order 12866; (2) Is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44...

  14. Development of a low noise 10K J-T refrigeration system. Technical progress report, 31 Aug-15 Oct 90

    SciTech Connect

    Little, W.A.

    1990-10-15

    This report summarizes work done on the development of a low noise, Joule-Thomson, microminiature refrigeration system. Progress has been made on the development of the pneumatic compressor drive system which will be used to operate the compressor to determine the compressor lifetime and refrigerator system performance. Work on the refrigerator itself also has progressed well with operation down to 20K now being achieved, and reliably reproduced. Work is underway on the heat exchanger section of the third stage of the refrigerator, the helium stage.

  15. Development of a low-noise 10 K J-T (Joule-Thomson) refrigeration system. Technical report (Final)

    SciTech Connect

    Little, W.A.

    1987-06-15

    This report summarizes work done on the development of a low-noise Joule-Thomson, microminiature refrigeration system designed for 10 K operation. Topics discussed include: calculation of phase diagram of mixtures of certain hydrocarbon gases with nitrogen using the Benedict-Webb-Rubin equation of state; the setup of a magnetron-enhanced sputtering system to allow sputtering a layer of adhesive on the glass substrates with a much-better-defined thickness than can be laid down using the older screen printing method; redesign of H/sub 2/ refrigerator test stage, redesign of mixed-gas heat exchanger, refrigerator fabrication, and gas cleaner.

  16. 75 FR 50945 - Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78...-02, Amendment 39-14242 (70 FR 52004, September 1, 2005), to require revisions to the TLS of the... Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and 3. Would not have a...

  17. Wind tunnel test of model target thrust reversers for the Pratt and Whitney aircraft JT8D-100 series engines installed on a 727-200 airplane

    NASA Technical Reports Server (NTRS)

    Hambly, D.

    1974-01-01

    The results of a low speed wind tunnel test of 0.046 scale model target thrust reversers installed on a 727-200 model airplane are presented. The full airplane model was mounted on a force balance, except for the nacelles and thrust reversers, which were independently mounted and isolated from it. The installation had the capability of simulating the inlet airflows and of supplying the correct proportions of primary and secondary air to the nozzles. The objectives of the test were to assess the compatibility of the thrust reversers target door design with the engine and airplane. The following measurements were made: hot gas ingestion at the nacelle inlets; model lift, drag, and pitching moment; hot gas impingement on the airplane structure; and qualitative assessment of the rudder effectiveness. The major parameters controlling hot gas ingestion were found to be thrust reverser orientation, engine power setting, and the lip height of the bottom thrust reverser doors on the side nacelles. The thrust reversers tended to increase the model lift, decrease the drag, and decrease the pitching moment.

  18. Development of a low-noise 10-K J-T refrigeration system. Technical progress report, 15 August 1986-15 February 1987

    SciTech Connect

    Little, W.A.

    1987-02-15

    This report summarizes work on the development of a low-noise Joule-Thomson, microminiature refrigeration system, designed for 10 K operation. Two events since the last report have had an important influence on the confirmation through a series of experimental measurements of the remarkable cooling power at 80 to 90 K of the nitrogen-hydrocarbon gas mixtures discussed briefly in the previous report. These experiments confirmed that these mixtures could give a refrigeration an order of magnitude greater than that attainable with argon or nitrogen at the same input pressures. In addition, it was recognized that this high efficiency allowed one to use a heat exchanger of substantially smaller surface area and a compressor designed for operation at much lower pressures. This lower-pressure operation would greatly reduce the wear of the piston seals and thereby prolong the life of the system. It was also discovered in the course of these measurements that the use of the gas mixtures resulted in virtually clog-free operation of the refrigerators.

  19. 76 FR 5066 - Airworthiness Directives; Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-28

    ...-14398 (70 FR 73361, December 12, 2005). That AD applies to the specified products. The NPRM published in the Federal Register on August 18, 2010 (75 FR 50942). That NPRM proposed to modify the TLS of the... ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will...

  20. 75 FR 50942 - Airworthiness Directives; Pratt & Whitney JT8D-7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ..., 2000 (65 FR 19477-78). Examining the AD Docket You may examine the AD docket on the Internet at http... AD 2005-25-05, Amendment 39- 14398 (70 FR 73361, December 12, 2005), to require revisions to the TLS.... Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034,...

  1. Effects of toroidal rotation shear and magnetic shear on thermal and particle transport in plasmas with electron cyclotron heating on JT-60U

    NASA Astrophysics Data System (ADS)

    Yoshida, M.; Honda, M.; Narita, E.; Hayashi, N.; Urano, H.; Nakata, M.; Miyato, N.; Takenaga, H.; Ide, S.; Kamada, Y.

    2015-07-01

    Increases in thermal and particle transport with electron cyclotron heating (ECH) that are observed in many tokamaks can be a critical issue in establishing ITER operational scenarios with electron heating. To address the issues, conditions with no increase in the thermal and particle transport with ECH have been experimentally investigated in positive magnetic shear, weak magnetic shear (WS) and reversed magnetic shear plasmas with internal transport barrier in the ion channel. The ion heat diffusivity (?i) around the internal transport barrier in the ion temperature remains constant with ECH when a large negative toroidal rotation shear (|dV?/dr| > 4 105 s-1) is formed before the ECH. On the other hand, ?i increases on the condition that the toroidal rotation shear is small or positive. The characteristics do not depend on magnetic shear, the electron to ion temperature ratio (Te/Ti) and ECH power. The electron heat diffusivity stays constant with ECH when the magnetic shear is negative. Effective particle transport remains constant or reduces during ECH under the condition of negative magnetic shear. An observation indicates that there is no threshold of the negative magnetic shear or a very small one for the electron channel sustainment; the electron thermal and particle confinement is maintained during ECH with a small negative magnetic shear in the WS operation.

  2. Genetics Home Reference: hereditary diffuse gastric cancer

    MedlinePlus

    ... Ligtenberg MJ, Figueiredo J, van Riel E, Sijmons RH, Plukker JT, van Hillegersberg R, Dekker E, Oliveira ... 26398. Epub 2011 Oct 23. Kluijt I, Sijmons RH, Hoogerbrugge N, Plukker JT, de Jong D, van ...

  3. Study of turbofan engines designed for low energy consumption

    NASA Technical Reports Server (NTRS)

    Gray, D. E.

    1976-01-01

    The near-term technology improvements which can reduce the fuel consumed in the JT9D, JT8D, and JT3D turbofans in commercial fleet operation through the 1980's are identified. Projected technology advances are identified and evaluated for new turbofans to be developed after 1985. Programs are recommended for developing the necessary technology.

  4. Characterization of multielectron dynamics in molecules: A multiconfiguration time-dependent Hartree-Fock picture

    SciTech Connect

    Ohmura, Shu; Kono, Hirohiko; Oyamada, Takayuki; Kato, Tsuyoshi; Nakai, Katsunori; Koseki, Shiro

    2014-09-21

    Using the framework of multiconfiguration theory, where the wavefunction ?(t) of a many-electron system at time t is expanded as ?(t)=?{sub I}C{sub I}(t)?{sub I}(t) in terms of electron configurations (?{sub I}(t)), we divided the total electronic energy E(t) as E(t)=?{sub I}|C{sub I}(t)|{sup 2}E{sub I}(t) . Here E{sub I}(t) is the instantaneous phase changes of C{sub I}(t) regarded as a configurational energy associated with ?{sub I}(t). We then newly defined two types of time-dependent states: (i) a state at which the rates of population transfer among configurations are all zero; (ii) a state at which (E{sub I}(t)) associated with the quantum phases of C{sub I}(t) are all the same. We call the former time-dependent state a classical stationary state by analogy with the stationary (steady) states of classical reaction rate equations and the latter one a quantum stationary state. The conditions (i) and (ii) are satisfied simultaneously for the conventional stationary state in quantum mechanics. We numerically found for a LiH molecule interacting with a near-infrared (IR) field ?(t) that the condition (i) is satisfied whenever the average velocity of electrons is zero and the condition (ii) is satisfied whenever the average acceleration is zero. We also derived the chemical potentials ?{sub j}(t) for time-dependent natural orbitals ?{sub j}(t) of a many-electron system. The analysis of the electron dynamics of LiH indicated that the temporal change in ??{sub j}(t) ? ?{sub j}(t) + ?(t) d{sub j}(t) ? ?{sub j}(0) correlates with the motion of the dipole moment of ?{sub j}(t), d{sub j}(t). The values ??{sub j}(t) are much larger than the energy ?{sub j}(t) directly supplied to ?{sub j}(t) by the field, suggesting that valence electrons exchange energy with inner shell electrons. For H{sub 2} in an intense near-IR field, the ionization efficiency of ?{sub j}(t) is correlated with ??{sub j}(t). Comparing ??{sub j}(t) to ?{sub j}(t), we found that energy accepting orbitals of ??{sub j}(t) > ?{sub j}(t) indicate high ionization efficiency. The difference between ??{sub j}(t) and ?{sub j}(t) is significantly affected by electron-electron interactions in real time.

  5. Analysis of a tobacco vector and its actions in china: the activities of japan tobacco

    PubMed Central

    2010-01-01

    Japan Tobacco (JT) is the third largest tobacco company in the world, and China, the world's largest tobacco consumer, is one of the most important targets for JT. To provide information for tobacco control, we reviewed and analyzed JT and its tactics and strategies in the Chinese market mainly by systematic examination of documents which are made available in the University of California, San Francisco Legacy Tobacco Documents Library. As a result, JT has had a special interest to expand sales of its cigarettes in the Chinese market. PMID:20979655

  6. Vaginal sponge and spermicides

    MedlinePlus

    Birth control - over the counter; Contraceptives - over the counter ... Elsevier; 2011:chap 26. Jensen JT, Mishell DR. Family planning: contraception, sterilization, and pregnancy termination. In: Lentz GM, ...

  7. Percolation features of cooperative Jahn-Teller systems: Ising EFT framework

    NASA Astrophysics Data System (ADS)

    Moujaes, Elie A.; Abou Ghantous, Michel

    2014-08-01

    Elastic exchange between two nearest Jahn-Teller (JT) centers in two or three dimensional dense crystals, can give an ordered macroscopic distortion known as cooperative JT effect (CJTE). A very diluted JT crystal does not show this effect. In the dynamic JT effect (DJTE), tunneling between different equivalent distorted wells has a pronounced influence on the CJTE. We investigate this phenomenon using a progressive increase in the concentration of these centers in the JT crystals, based on a bond percolation vector spin analogy technique within the framework of effective field theory (EFT). Mean field theory (MFT) was extensively used in previous studies of CJTE; however it neither includes correlation between JT centers in the lattice due to the complexity of the distortion field in the crystal nor the effect of tunneling between wells. We resort to an alternative procedure, by describing a JT center as a pseudo-spin vector , induced to represent the degenerate JT-distorted states, where two nearest JT centers interact via an elastic exchange described by an Ising type spin interaction. The DJTE is considered to be similar to an elastic transverse field term in the Hamiltonian portraying the effect of tunneling between equivalent wells in the adiabatic potential energy surface (APES). We will be particularly discussing S = 1, S = 3/2 and S = 5/2 spin cases, where 2 S + 1 wells in the APES are present and what JT systems they actually represent, with a percolative mechanism applied to the interactions between different JT centers. The different lattices are distinguished by their coordination numbers. Strong tunneling effects can suppress the CJTE and lead to a new state of criticality. Generalizations to higher spin systems will be obtained using a scaling technique. For the relevant distortions, we determine single site correlations, the macroscopic average distortion describing a structural phase transition and the elastic isothermal susceptibility as a function of temperature. The critical bond percolation threshold and the critical tunneling parameter are also obtained.

  8. 14 CFR 36.1 - Applicability and definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... certification procedure. Editorial Note: For Federal Register citations affecting § 36.1, see the List of CFR..., except for airplanes that are powered by Pratt & Whitney Turbo Wasp JT3D series engines; (ii) December 31... & Whitney Turbo Wasp JT3D series engines; and (iii) December 31, 1974, for airplanes with maximum weights...

  9. 14 CFR 36.1 - Applicability and definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Federal Register citations affecting § 36.1, see the List of CFR Sections Affected, which appears in the...,000 pounds, except for airplanes that are powered by Pratt & Whitney Turbo Wasp JT3D series engines... powered by Pratt & Whitney Turbo Wasp JT3D series engines; and (iii) December 31, 1974, for airplanes...

  10. 14 CFR 36.1 - Applicability and definitions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... certification procedure. Editorial Note: For Federal Register citations affecting § 36.1, see the List of CFR..., except for airplanes that are powered by Pratt & Whitney Turbo Wasp JT3D series engines; (ii) December 31... & Whitney Turbo Wasp JT3D series engines; and (iii) December 31, 1974, for airplanes with maximum weights...

  11. Analysis of two-stage Joule-Thomson expansion

    NASA Astrophysics Data System (ADS)

    Narasaki, Katsuhiro

    2016-03-01

    To cool far infrared detectors for infrared observation or superconductor-insulator-superconductor (SIS) mixers for atmospheric observation, 1 K-class and 4 K-class coolers have been developed. These coolers consist of a two-stage Stirling cooler for pre-cooling and a Joule-Thomson (JT) cooler with a single JT valve. This paper presents descriptions of theoretical analyses based on enthalpy balance to elucidate the benefits of a two-stage JT valve type compared with those of a single JT valve type in a JT cooler. First, relational expressions for heat balance analysis of enthalpy for single-stage JT expansion are introduced. Then similar relational expressions for two-stage JT expansion are introduced under some assumptions. Results of heat balance analyses using several parameters demonstrated that, using two-stage JT expansion, the cooling capacity for a 1 K-class cooler is improved by 100%; that of a 4 K-class cooler is improved by about 30%.

  12. Construction of new cloning, lacZ reporter and scarless-markerless suicide vectors for genetic studies in Aggregatibacter actinomycetemcomitans.

    PubMed

    Juárez-Rodríguez, María Dolores; Torres-Escobar, Ascención; Demuth, Donald R

    2013-05-01

    To elucidate the putative function of a gene, effective tools are required for genetic characterization that facilitate its inactivation, deletion or modification on the bacterial chromosome. In the present study, the nucleotide sequence of the Escherichia coli/Aggregatibacter actinomycetemcomitans shuttle vector pYGK was determined, allowing us to redesign and construct a new shuttle cloning vector, pJT4, and promoterless lacZ transcriptional/translational fusion plasmids, pJT3 and pJT5. Plasmids pJT4 and pJT5 contain the origin of replication necessary to maintain shuttle vector replication. In addition, a new suicide vector, pJT1, was constructed for the generation of scarless and markerless deletion mutations of genes in the oral pathogen A. actinomycetemcomitans. Plasmid pJT1 is a pUC-based suicide vector that is counter-selectable for sucrose sensitivity. This vector does not leave antibiotic markers or scars on the chromosome after gene deletion and thus provides the option to combine several mutations in the same genetic background. The effectiveness of pJT1 was demonstrated by the construction of A. actinomycetemcomitans isogenic qseB single deletion (ΔqseB) mutant and lsrRK double deletion mutants (ΔlsrRK). These new vectors may offer alternatives for genetic studies in A. actinomycetemcomitans and other members of the HACEK (Haemophilus spp., A. actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae) group of Gram-negative bacteria. PMID:23353051

  13. Engine component improvement program: Performance improvement. [fuel consumption

    NASA Technical Reports Server (NTRS)

    Mcaulay, J. E.

    1979-01-01

    Fuel consumption of commercial aircraft is considered. Fuel saving and retention components for new production and retrofit of JT9D, JT8D, and CF6 engines are reviewed. The manner in which the performance improvement concepts were selected for development and a summary of the current status of each of the 16 selected concepts are discussed.

  14. A GLIMPSE INTO THE EYE OF THE EMERGENCY RESPONSE AT EPA KATRINA AND RITA

    EPA Science Inventory

    This presentation was given at the Texas Environmental Health Association Annual Meeting in Round Rock, TX on October 12, 2005. The keynote address was focused on the conditions after Katrins, organizing response, field response, EPA's role in emergency response, what is EPA doi...

  15. Anomalous high-pressure Jahn-Teller behavior in CuWO4.

    PubMed

    Ruiz-Fuertes, J; Segura, A; Rodríguez, F; Errandonea, D; Sanz-Ortiz, M N

    2012-04-20

    High-pressure optical-absorption measurements performed in CuWO(4) up to 20 GPa provide experimental evidence of the persistence of the Jahn-Teller (JT) distortion in the whole pressure range both in the low-pressure triclinic and in the high-pressure monoclinic phase. The electron-lattice couplings associated with the e(g)(E⊗e) and t(2g)(T⊗e) orbitals of Cu(2+) in CuWO(4) are obtained from correlations between the JT distortion of the CuO(6) octahedron and the associated structure of Cu(2+) d-electronic levels. This distortion and its associated JT energy (E(JT)) decrease upon compression in both phases. However, both the distortion and associated E(JT) increase sharply at the phase-transition pressure (P(PT)=9.9 GPa), and we estimate that the JT distortion persists for a wide pressure range not being suppressed up to 37 GPa. These results shed light on the transition mechanism of multiferroic CuWO(4), suggesting that the pressure-induced structural phase transition is a way to minimize the distortive effects associated with the toughness of the JT distortion. PMID:22680738

  16. Clogging of Joule-Thomson Devices in Liquid Hydrogen-Lunar Lander Descent Stage Operating Regime

    NASA Astrophysics Data System (ADS)

    Jurns, J. M.

    2010-04-01

    Joule-Thomson (J-T) devices have been identified as critical components for future space exploration missions. The NASA Constellation Program lunar architecture considers LOX/LH2 propulsion for the lunar lander descent stage main engine an enabling technology, ensuring the cryogenic propellants are available at the correct conditions for engine operation. This cryogenic storage system may utilize a Thermodynamic Vent System (TVS) that includes J-T devices to maintain tank fluid pressure and temperature. Previous experimental investigations have indicated that J-T devices may become clogged when flowing LH2 while operating at a temperature range from 20.5 K to 24.4 K. It has been proposed that clogging is due to a trace amount of metastable, supercooled liquid neon in the regular LH2 supply. In time, flow blockage occurs from accretion of solid neon on the orifice. This clogging poses a realistic threat to spacecraft propulsion systems utilizing J-T devices in cryogenic pressure control systems. TVS failure due to J-T clogging would prevent removal of environmental heat from the propellant and potential loss of mission. This report describes J-T clogging tests performed with LH2. Tests were performed in the expected Lunar Lander operating regime, and several methods were evaluated to determine the optimum approach to mitigating the potential risk of J-T clogging.

  17. Education for Engineers in Mitsubishi Heavy Industries

    NASA Astrophysics Data System (ADS)

    Ohsone, Masanori; Funakoshi, Makoto; Taguchi, Toshio

    In manufacturing companies, the importance of Off the Job Training (OffJT) is increasing, because there are not enough opportunities for On the Job Training (OJT) . Therefore, OffJT is required to further improve quality. Also it is required to enhance the skills of our engineers, as a substitute for OJT. Mitsubishi Heavy Industries has improved OffJT by using the same methods of quality improvement as those employed in our factories. It has also developed exercises to train engineers in complex multiple skills, thus improving their ability. We report the results of these efforts.

  18. Exploration of Home Economics Related Occupations in Clothing

    ERIC Educational Resources Information Center

    Thomas, Virginia F.; Plumb, Sandra

    1976-01-01

    A five-unit lesson plan is presented titled "Introduction to Careers in the Fashion Industry" which involved three sections of a ninth grade home economics class in an assembly line sewing experience in a clothing production factory. (JT)

  19. Gingivostomatitis

    MedlinePlus

    ... It may occur after infection with the herpes simplex virus type 1 (HSV-1), which also causes ... 2015:chap 174. Schiffer JT, Corey L. Herpes simplex virus. In: Bennett JE, ed. Mandell, Douglas, and ...

  20. Adult Education and Development: The Case of India

    ERIC Educational Resources Information Center

    Singh, Amrik

    1976-01-01

    A discussion of the historical influences on theory and practice of economic development in India and of the relationship between adult education efforts and the social changes which bring about development. (JT)

  1. Flight effects of fan noise

    NASA Technical Reports Server (NTRS)

    Chestnutt, D. (Editor)

    1982-01-01

    Simulation of inflight fan noise and flight effects was discussed. The status of the overall program on the flight effects of fan noise was reviewed, and flight to static noise comparisons with the JT15D engine were displayed.

  2. Jobs With Service Programs: Community Services

    ERIC Educational Resources Information Center

    Rones, Philip L.

    1976-01-01

    Reviews the kinds of community services available to older people within their communities through public and private agencies. Focus is on the senior center and such services as information and referral, transportation, counseling, recreation, education, and health. (JT)

  3. Considerations for an Institutional Grievance Procedure

    ERIC Educational Resources Information Center

    Persson, Leonard N.

    1976-01-01

    Guidelines are presented for developing and maintaining effective grievance procedures. The discussion is basic to development of procedures for all institutional groups, e.g. students, faculty, service workers. (Editor/JT)

  4. Achieving Salary Equity

    ERIC Educational Resources Information Center

    Nevill, Dorothy D.

    1975-01-01

    Three techniques are outlined for use by higher education institutions to achieve salary equity: salary prediction (using various statistical procedures), counterparting (comparing salaries of persons of similar rank), and grievance procedures. (JT)

  5. Study on a Miniature Mixed-gases Joule-Thomson Cooler Driven by an Oil-lubricated Mini-compressor for 120 K Temperature Ranges

    NASA Astrophysics Data System (ADS)

    Gong, M. Q.; Wu, J. F.; Yan, B.; Zou, X.; Zhuang, X. R.; Hu, Q. G.

    In this paper, a miniature J-T cooler using multicomponent mixtures was developed and tested, in which an oil-lubricated mini-compressor was used. Experimental tests on the performance of the miniature J-T cooler were carried out with two kinds of recuperative heat exchangers. One is a shell-and-tube heat exchanger, and the other is a plate-fin type recuperative heat exchanger with whereas a micro-channel configuration fabricated by the wire-electrode cutting method. The former one gave a no-load minimum temperature of 140 K, while the later one showsbetter performance. No-load minimum temperature of 110 K and about 4 W cooling capacity at 118 K were achieved with the plate-fin micro J-T cooler. Such miniature J-T coolers driven by oil-lubricated mini-compressors show good prospects in many applications.

  6. Eucalyptus oil overdose

    MedlinePlus

    ... PS, ed. Wilderness Medicine . 6th ed. Philadelphia, PA: Elsevier Mosby; 2012:chap 64. Maypole J, Woolf AD. ... Poisoning and Drug Overdose . 4th ed. Philadelphia, PA: Elsevier Saunders; 2007:chap 101. McMullan JT, Duvivier EH, ...

  7. Genital herpes

    MedlinePlus

    ... et al, eds. Dermatology . 3rd ed. Philadelphia, PA: Elsevier Mosby; 2012:chap 80. Palmore TN, Henderson DK. ... Practice of Infectious Diseases . 8th ed. Philadelphia, PA: Elsevier; 2014:chap 308. Schiffer JT and Corey L. ...

  8. Genetics Home Reference: fibrodysplasia ossificans progressiva

    MedlinePlus

    ... Glaser DL, LeMerrer M, Morhart R, Rogers JG, Smith R, Triffitt JT, Urtizberea JA, Zasloff M, Brown ... added]; Morhart, Rolf [added]; Rogers, John G [added]; Smith, Roger [added]; Triffitt, James T [added]; Urtizberea, J ...

  9. Jobs with Service Programs: Home Services

    ERIC Educational Resources Information Center

    Kahl, Anne

    1976-01-01

    A review of the kinds of jobs available in services developed to help the homebound elderly: Home health care, homemaker-home health aide, chore service, home repair and maintenance, home-delivered meals, telephone reassurance, and friendly visiting. (JT)

  10. Authority v. Experience in Higher Education

    ERIC Educational Resources Information Center

    Cornwall, Malcolm G.

    1975-01-01

    Discusses current practices and procedures in British higher education (particularly in the teaching of science) in relationship to the values it upholds. Examines and evaluates alternative models for the project oriented experiments in Denmark, West Germany, and the Netherlands. (JT)

  11. ENVIRONMENTAL IMPACTS AND MONITORING: A HISTORICAL PERSPECTIVE ON THE USE OF NATURAL ATTENUATION FOR SUBSURFACE REMEDIATION: BOOK CHAPTER

    EPA Science Inventory

    BOOK CHAPTER NRMRL-ADA-01128 West, CC, and Wilson*, J.T. "Environmental Impacts and Monitoring: A Historical Perspective on the Use of Natural Attenuation for Subsurface Remediation." In: Environmental Chemistry: Fate, ...

  12. Detection of the Magnetic Dipole-Allowed Origin Band of the widetilde{A}←widetilde{X} Transition of the Nitrate Radical NO_3

    NASA Astrophysics Data System (ADS)

    Takematsu, Kana; Eddingsaas, Nathan; Okumura, Mitchio; Stanton, John

    2009-06-01

    Despite its simplicity and atmospheric significance, the lowest electronic states of NO_3 remain poorly understood. The widetilde{A}^2E^'' state is Jahn-Teller (JT) active and is pseudo-JT coupled to the ground widetilde{X}^2A_2^' and excited widetilde{B}^2E^'' states. While the band origin 0^{0}_{0} of the widetilde{A}←widetilde{X} transition is purely electric forbidden, the cavity ringdown spectrum of the vibronically-allowed widetilde{A}←widetilde{X} bands has shown rotationally-resolvable structures. We have detected the magnetic dipole-allowed origin (˜7060 cm^{-1}) via CRD spectroscopy. Analysis of the band contour along with its implications of the JT/Pseudo-JT couplings in the dark widetilde{A} state of NO_3 will be discussed.

  13. Jobs With Service Programs: Legal Services

    ERIC Educational Resources Information Center

    Rones, Philip L.

    1976-01-01

    A discussion of how legal services are becoming more responsive to the needs of the elderly with focus on job training and opportunities for lawyers, paralegals, and community service advisors (CSAs). (JT)

  14. Cool's Clams Casino

    ERIC Educational Resources Information Center

    Cobey, Paul; Williams, David E.

    1977-01-01

    A mathematical game that reinforces basic multiplication facts, strengthens concepts of factors and multiples, and also provides arithmetic drill is described. Four variations of the game are also provided. (JT)

  15. Organizing for Accountability

    ERIC Educational Resources Information Center

    Bennis, Warren

    1975-01-01

    A college president challenges personnel administrators to play a leadership role in human resource management. Notes the need for career development programs for middle managers particularly and recommends an organizational development approach to faculty and staff career development. (JT)

  16. Glass Walls.

    ERIC Educational Resources Information Center

    Smith, Jeanne A.

    1980-01-01

    Relates some of the author's experiences while teaching on the Pine Ridge (South Dakota) Sioux Reservation, showing how learning barriers can be broken with a little understanding between teacher and students. (JT)

  17. Advances in Joule-Thomson cooling

    NASA Astrophysics Data System (ADS)

    Little, W. A.

    The Joule-Thomson (J-T) cooling effect from the expansion of a nonideal gas, is one of the oldest methods known for the generation of cryogenic temperatures. It is the simplest to use, but, in many circumstances, is one of the least efficient. However, recent developments of J-T coolers using more complex cycles, multi-stage construction, special gas mixtures, and novel methods of fabrication have greatly improved the attainable efficiency of this type of cooler. These developments have made the J-T refrigerator competitive in many situations with other refrigerators which use superficially more efficient cooling cycles. In addition, the absence of mechanical noise or vibration, their innate simplicity, their small size, and low mass give these J-T refrigerators a number of additional advantages over Stirling and other such refrigerators. These developments and the underlying reasons for these improvements are discussed.

  18. Academic Interest Rates and Grade Inflation

    ERIC Educational Resources Information Center

    Davidson, James F.

    1975-01-01

    Traces the causes and effects of the devaluation of honors grades over the past fifteen years noting particularly effects on transcripts and grades as a means of exchange and suggesting faculty responsibility for restoration of academic standards. (JT)

  19. The Accounting Curriculum in College

    ERIC Educational Resources Information Center

    Gustafson, George Axel

    1975-01-01

    In discussing the need for combination of theory and practice in the college accounting curriculum, the author presents a conceptual framework for the body of knowledge which teaches the student principles and puts them into practice through illustrations. (JT)

  20. Aortic aneurysm repair - endovascular - discharge

    MedlinePlus

    ... term outcome of open or endovascular repair of abdominal aortic aneurysm. N Engl J Med . 2010 May 20;362( ... 20484396 . Greenhalgh RM, Powell JT. Endovascular repair of abdominal aortic aneurysm. N Engl J Med . 2008 Jan 31;358( ...

  1. Female condoms

    MedlinePlus

    ... female condoms at most drugstores, STI clinics, and family planning clinics. You need to plan to have a ... Jensen JT, Mishell DR. Family planning: contraception, ... Katz VL, eds. Comprehensive Gynecology . 6th ed. Philadelphia, ...

  2. Emergency contraception

    MedlinePlus

    Morning-after pill; Postcoital contraception; Birth control - emergency; Plan B ... Mosby; 2012:chap 92. Jensen JT, Mishell DR. Family planning: contraception, sterilization, and pregnancy termination. In: Lentz GM, ...

  3. Birth control pills - overview

    MedlinePlus

    Contraception - pills - hormonal methods; Hormonal birth control methods; Birth control pills; Contraceptive pills; BCP; OCP ... Mosby; 2008:chap 20. Jensen JT, Mishell DR. Family planning: contraception, sterilization, and pregnancy termination. In: Lentz GM, ...

  4. Hey Mister! It's Upside Down!

    ERIC Educational Resources Information Center

    Gilbert, Robert K.

    1977-01-01

    A graphing activity which allows students to work independently of the teacher and the textbook is described. The activity involves providing data in order to develop the skills necessary for interpreting the collected information. (JT)

  5. Tubal ligation

    MedlinePlus

    Sterilization surgery - female; Tubal sterilization; Tube tying; Tying the tubes; Hysteroscopic tubal occlusion procedure ... Jensen JT, Mishell DR Jr. Family planning: contraception, sterilization, and pregnancy termination. In: Lentz GM, Lobo RA, ...

  6. Tubal ligation - discharge

    MedlinePlus

    Sterilization surgery - female - discharge; Tubal sterilization - discharge; Tube tying - discharge; Tying the tubes - discharge ... Jensen JT, Mishell DR Jr. Family planning: contraception, sterilization, and pregnancy termination. In: Lentz GM, Lobo RA, ...

  7. Emerging Consequences of Financing Private Colleges with Public Money

    ERIC Educational Resources Information Center

    Smith, Michael R.

    1975-01-01

    The question of public aid to private colleges is analyzed in historical perspective and in terms of current trends and future outlook followed by a presentation of applicable federal and state supreme court decisions. (JT)

  8. Teasing Hamsters in Electric Cages?

    ERIC Educational Resources Information Center

    Page, Colin Flood

    1975-01-01

    Reviews several studies that examine the climate of feeling surrounding training courses for college teachers and the general social atmosphere of the job into which the trainee is being initiated. (JT)

  9. Metric Measurement and Instructional Television

    ERIC Educational Resources Information Center

    Meiring, Steven P.

    1977-01-01

    The television series "MeasureMetric," an instructional series introducing length, area, volume, mass, and temperature measurement in metric settings, is described. Guidelines are given for using the series as a complete learning unit. (JT)

  10. Freedom of Expression at Yale

    ERIC Educational Resources Information Center

    AAUP Bulletin, 1975

    1975-01-01

    A report of the Committee on Freedom of Expression at Yale appointed by the president to examine the condition of free expression, peaceful dissent, mutual respect and tolerance at Yale and to draft recommendations for maintenance of those principles. (JT)

  11. Evaluation of a Heart Sound Simulator in Teaching Cardiac Ausculation

    ERIC Educational Resources Information Center

    Harley, Alexander

    1976-01-01

    Results obtained from a study designed to assess the effectiveness of teaching with heart sound simulation in improving skill in clinical ausculation suggest the usefulness of further study, particularly that involving comparison techniques. (JT)

  12. Design for a Training Centre

    ERIC Educational Resources Information Center

    Canadian Training Methods, 1976

    1976-01-01

    Briefly describes the design for Cantrakon (Canadian Training and Conference Centre) being built for $8 million by Mont Ste-Marie Ltd. to provide first-class conference facilities to attract Canadian government and industry and also international conferences. (JT)

  13. Discretionary Review by the Occupational Safety and Health Review Commission: Is It Necessary?

    ERIC Educational Resources Information Center

    Moran, Robert D.

    1974-01-01

    Deficiencies in the Occupational Safety and Health Review Commission (OSAHRC), a court system created to carry out adjudicatory functions under the Williams-Steiger Occupational Safety and Health Act of 1970, are exposed and alternative solutions offered. (JT)

  14. Joule-Thomson Expander Without Check Valves

    NASA Technical Reports Server (NTRS)

    Chan, C. K.; Gatewood, J. R.

    1989-01-01

    Cooling effected by bidirectional, reciprocating flow of gas. Type of Joule-Thomson (J-T) expander for cryogenic cooling requires no check valves to prevent reverse flow of coolant. More reliable than conventional J-T expander, containing network of check valves, each potential source of failure. Gas flows alternately from left to right and right to left. Heat load cooled by evaporation of liquid from left or right compartment, whichever at lower pressure.

  15. Local Structure of La1-xSrxCoO3 determined from EXAFS and neutron PDF studies

    SciTech Connect

    Sundaram, N.; Jiang, Y.; Anderson, I. E.; Belanger, D. P.; Booth, C. H.; Bridges, F.; Mitchell, J. F.; Proffen, Th.; Zheng, H.

    2009-01-26

    The combined local structure techniques, extended x-ray absorption fine structure (EXAFS) and neutron pair distribution function analysis, have been used for temperatures 4<= T<= 330 K to rule out a large Jahn-Teller (JT) distortion of the Co-O bond in La1?xSrxCoO3 for a significant fraction of Co sites (x<= 0.35), indicating few, if any, JT-active, singly occupied eg Co sites exist.

  16. Narrow Complex Tachycardia: What is the Mechanism?

    PubMed

    Refaat, Marwan M; Scheinman, Melvin; Badhwar, Nitish

    2016-03-01

    This article presents a diagnostic dilemma in which atrioventricular nodal reentrant tachycardia (AVNRT) and junctional tachycardia (JT) were differentiated based on tachycardia initiation with atrial extrastimulus as well as on the response to progressive decremental atrial extrastimuli. The progressive increase in A2H2' and H2H2' in response to atrial extrastimuli favors reentry as the mechanism of the tachycardia. This is a novel mechanistic differentiation of AVNRT from focal JT. PMID:26920172

  17. Advanced laser shearography inspection of turbo-fan engine composite fan cases

    NASA Astrophysics Data System (ADS)

    Lape, Dale; Newman, John W.; Craig, David

    1995-07-01

    Shearography inspection techniques have been developed and implemented for the inspection of aluminum honeycomb turbofan aircraft engine fan cases for the JT15D-5D. Shearography has yielded improved sensitivity to unbonds and throughput over ultrasonic techniques formerly used in the production inspection. This paper discusses vacuum stress shearography, test method verification on the JT15D-5D fan case and shearography data correlation with destructive evaluation of test parts.

  18. A cryogenic heat exchanger with bypass and throttling and its thermodynamic analysis

    NASA Astrophysics Data System (ADS)

    Tao, X.; Liu, D. L.; Wang, L. Y.; Shen, J.; Gan, Z. H.

    2015-12-01

    A precooled Joule-Thomson (J-T) cooler refrigerates at liquid helium temperature. Its third stage heat exchanger works below 20 K. Hot fluid cannot be sufficiently cooled due to nonidealism of the heat exchanger and helium-4 properties. In a J-T cycle of low pressure ratio, the heat exchanger with bypass and throttling improves the refrigeration capacity. Bypass and throttling reduces the temperature difference and entropy generation within the heat exchanger.

  19. Vibronic Analysis of the widetilde{A}^2 E^'' State of NO_3 Radical

    NASA Astrophysics Data System (ADS)

    Codd, Terrance J.; Roudjane, Mourad; Chen, Ming-Wei; Miller, Terry A.

    2013-06-01

    The nitrate radical is a key reactant in atmospheric chemistry leading to the formation of acid rain and is the primary oxidant in the night sky. The widetilde{A}^2 E^'' state of NO_3 is doubly degenerate and is therefore subject to Jahn-Teller (JT) coupling through the degenerate in-plane stretch and bend modes (ν_3 and ν_4 respectively). We have taken a moderate resolution CRDS spectrum of the widetilde{A}^2 E^''-widetilde{X}^2 A_2' transition of the NO_3 radical under jet-cooled conditions. We resolve ˜20 vibronic transitions and are able to assign many using an independent anharmonic oscillator model as was presented previously. In order to gain a deeper understanding of the nature of the JT effect in this electronic state we have performed a vibronic analysis including linear and quadratic JT coupling terms for ν_3 and ν_4 and possible bilinear coupling between the totally symmetric stretch, ν_1, and ν_4. We conclude that the JT coupling in ν_4 is quite weak. Satisfactory spectral fits can be obtained assuming weak JT coupling for ν_3 also, though there is some evidence of strong JT coupling for ν_3 and the strengths and weaknesses of each case are discussed. Codd, T. et al. 67^{th} Int. Symp. Molec. Spec. (2012)}

  20. An Application of Space-Based Gas Mixtures for Joule-Thompson Cryocoolers

    NASA Astrophysics Data System (ADS)

    Arkhipov, V. T.; Yevdokimova, O. V.; Lobko, M. P.; Yakuba, V. V.

    An extension of deepspace research, specifically, the work done on Alpha program, will inevitably require new and different cryostating systems. The primary differences will be in the areas of cooling power and temperature. One variant which can be used with J-T cryocoolers is the application of diverse gas mixtures which can work over a large temperature range. We have found that the J-T cycle is an efficient application of mixed gas working fluids, being very similar to a vapor-compression cycle utilized in household refrigerants. The simplicity and viability of a J-T design and the associated minimal heat losses compensate for theoretical efficiency ratio of Stirling-type machines. Simultaneously, the J-T machines are never restricted in terms of output power and contain no moving parts in the cold zone resulting in minimal vibration during operation. The effective cooling of these systems allows parallel cooling of multiple objects. Finally in long-life system designs these cryocooler systems are feasibly coupled with phase-transition thermal storage accumulators. The application of such J-T systems is especially efficient under space conditions, due to the fact that there is an option to use at low temperatures a radiation release unit for the outlet of compression heat and for preliminary cooling of the system. This is not possible for terrestrial applications. Particularly, obtaining the -10 to 100 (C temperature range is feasible through the use of low As/(( - coefficient coatings; shade screens; or radiator unit orientations. Computational and experimental research has provided us high efficiency gas-mixture J-T cryocooler results between 60 to 100K cooling temperatures. We have actual space systems which were tested and operated for 80-90 K with efficiencies of 20 to 25 W/W. The authors of this research have studied various gas mixtures as candidates for use with simple J-T single contour J-T systems. We have seen resultant reduction of energy consumption by 2-3 times and decreases in temperatures from the 30-60( C range to -10 to 10( C range. We have also seen a dramatic reduction in the working pressure and the P/P pressure ratios within the cycle. We have gradually evolved into the application of simpler and more reliable working mixtures and employed more reliable single-stage compressors. In addition, the use of J-T contour gas mixtures for pre-cooling down to 35-40 K temperatures results in higher efficiency 2-stage J-T cryocoolers with similar overall results to the single stage systems.

  1. SU-E-T-187: Feasibility Study of Stereotactic Liver Radiation Therapy Using Multiple Divided Partial Arcs in Volumetric Modulated Arc Therapy

    SciTech Connect

    Lin, Y; Ozawa, S; Tsegmed, U; Nakashima, T; Shintaro, T; Ochi, Y; Kawahara, D; Kimura, T; Nagata, Y

    2014-06-01

    Purpose: To verify volumetric modulated arc therapy (VMAT) using flattening filter free (FFF) mode with jaw tracking (JT) feature for single breath hold as long as 15 s per arc in liver stereotactic body radiation therapy (SBRT) against intensity modulated radiation therapy (IMRT) FFF-JT. Methods: Ten hepatocellular carcinoma (HCC) cases were planned with 10 MV FFF using Pinnacle3 treatment planning system which delivered by TrueBeam to administer 48 Gy/ 4 fractions. Eight non-coplanar beams were assigned to IMRT using step-and-shoot technique. For VMAT, two or three non-coplanar partial arcs (up to 180 degrees) were further divided into subarcs with gantry rotation less than 80 degrees to limit delivery time within 15 s. Dose distributions were verified using OCTAVIUS II system and pass rates were evaluated using gamma analysis with criteria of 3%/3 mm at threshold of 5% to the maximum dose. The actual irradiation time was measured. Results: The VMAT-FFF-JT of partial-arcs with sub-divided arcs was able to produce a highly conformal plan as well as IMRT-FFF-JT. Isodose lines and DVH showed slight improvement in dosimetry when JT was employed for both IMRT and VMAT. Consequently, VMAT-FFF-JT was superior in reducing the dose to liver minus gross tumor volume. VMAT-FFF-JT has shorter total treatment time compared with 3D conformal radiation therapy (3D-CRT) FFF because the gantry was rotated simultaneously with the beam delivery in VMAT. Moreover, due to the small and regular shape of HCC, VMAT-FFF-JT offered less multileaf collimator motion, thus the interplay effect is expected to be reduced. The patient specific QA of IMRT and VMAT acquired the pass rates higher than 90%. Conclusion: VMAT-FFF-JT could be a promising technique for liver SBRT as the sub-divided arcs method was able to accommodate a single breath hold irradiation time of less than 15 s without deterioration of the dose distribution compared with IMRT-FFF-JT.

  2. Anomalous High-Pressure Jahn-Teller Behavior in CuWO4

    NASA Astrophysics Data System (ADS)

    Ruiz-Fuertes, J.; Segura, A.; Rodríguez, F.; Errandonea, D.; Sanz-Ortiz, M. N.

    2012-04-01

    High-pressure optical-absorption measurements performed in CuWO4 up to 20 GPa provide experimental evidence of the persistence of the Jahn-Teller (JT) distortion in the whole pressure range both in the low-pressure triclinic and in the high-pressure monoclinic phase. The electron-lattice couplings associated with the eg(E⊗e) and t2g(T⊗e) orbitals of Cu2+ in CuWO4 are obtained from correlations between the JT distortion of the CuO6 octahedron and the associated structure of Cu2+ d-electronic levels. This distortion and its associated JT energy (EJT) decrease upon compression in both phases. However, both the distortion and associated EJT increase sharply at the phase-transition pressure (PPT=9.9GPa), and we estimate that the JT distortion persists for a wide pressure range not being suppressed up to 37 GPa. These results shed light on the transition mechanism of multiferroic CuWO4, suggesting that the pressure-induced structural phase transition is a way to minimize the distortive effects associated with the toughness of the JT distortion.

  3. Continuous group invariances of linear Jahn-Teller systems in icosahedral symmetry: extension to direct sum electronic spaces

    NASA Astrophysics Data System (ADS)

    Wiseman, Robin D.

    1998-09-01

    Previous results for the generation of linear, icosahedral, Jahn-Teller (JT) Hamiltonians with continuous group symmetries are extended. It is demonstrated that it is possible to define electronic generalized tensor operators on a direct sum electronic space such that a set of these operators is closed under commutation with another set of electronic generalized tensor operators which act as the generators of a continuous group. The normal modes carrying irreducible representations of the continuous group are then coupled `equally' to produce a JT Hamiltonian which is invariant under the operations of the continuous group. The continuous groups generated on the direct sum spaces 0305-4470/31/37/022/img1, 0305-4470/31/37/022/img2, 0305-4470/31/37/022/img3 and 0305-4470/31/37/022/img4 are discussed in detail. These additional continuous groups are of interest when the lowest JT states of certain icosahedral JT systems (such as some of those found in 0305-4470/31/37/022/img5) are modelled. The additional continuous group symmetry allows an analytic diagonalization of the linear JT matrix to be provided and thus facilitates an exact treatment of the vibronic ground state for these models.

  4. Development of 1K-class Joule-Thomson cryocooler for next-generation astronomical mission

    NASA Astrophysics Data System (ADS)

    Sato, Yoichi; Sawada, Kenichiro; Shinozaki, Keisuke; Sugita, Hiroyuki; Mitsuda, Kazuhisa; Yamasaki, Noriko Y.; Nakagawa, Takao; Tsunematsu, Shoji; Ootsuka, Kiyomi; Narasaki, Katsuhiro

    2016-03-01

    This paper reports on the development of a 1K-class Joule-Thomson (JT) cryocooler in Japan for application to upcoming next-generation astronomy missions. In this development, engineering models (EMs) were designed and manufactured for verification tests. The survival of the models in the mechanical and thermal vacuum environment tests of the JT compressors was proven to be possible with stable compression performance. In addition, the electromagnetic noise and disturbance force associated with the JT compressors were evaluated. Gas analysis showed that the estimated total amount of CO2 gas contaminant was less than the getter capacity for the required lifetime. A nominal cooling power of 10 mW at 1.7 K was verified using the EM test units.

  5. Negative ion beam programs at JAERI

    SciTech Connect

    Ohara, Y. )

    1990-08-05

    Three negative ion beam programs for nuclear fusion research are proposed at the Japan Atomic Energy Research Institute (JAERI): a 500 keV, 10 MW deuterium neutral beam injection (NBI) for heating and current drive in the JT-60U tokamak, a 0.5/1 MeV, 50 MW deuterium beam injection for the Fusion Experimental Reactor (FER), and a 2 MeV, 20 mA lithium beam injection for ion temperature measurement in the JT-60U. The 500 keV negative-ion-based NBI system for the JT-60U will be developed in the first step, followed by the development of the reactor relevant 0.5/1 MeV NBI system. This two step development mitigates the risk in developing a MeV class NBI system.

  6. Joule-Thomson cryogenic cooler with extremely high thermal stability

    NASA Technical Reports Server (NTRS)

    Bard, Steven; Wu, J. J.; Trimble, Curt

    1991-01-01

    An 80-K Joule-Thomson (J-T) cooling system designed for the Probe Infrared Laser Spectrometer (PIRLS) proposed for the Huygens Titan Probe of the Cassini Saturn orbiter mission is presented. The cryogenic cooling requirements of the PIRLS instrument are listed, and the cooler system design including details of a J-T cryostat, cold head, and dewar design is described along with the results of a thermal modeling effort and lab cooler performance testing. It is shown that by using active feedback temperature control of the cold head in combination with the self-regulating action of the J-T cryostat, a temperature stability of less than 0.1 mK/min is achieved by the cooler weighting 1.8 kg.

  7. Potential improvements in turbofan engine fuel economy

    NASA Technical Reports Server (NTRS)

    Hines, R. W.; Gaffin, W. O.

    1976-01-01

    The method developed for initial evaluation of possible performance improvements in the NASA Aircraft Energy Efficiency Program, directed toward improving the fuel economy of turbofan engines, is outlined, and results of the evaluation of 100 candidate engine modifications are presented. The study indicates that fuel consumption improvements of as much as 5% may be possible in current JT3D, JT8D, and JT9D turbofan engines. Aerodynamic, thermodynamic, material, and structural advances are expected to yield fuel consumption improvements on the order of 10 to 15% in advanced turbofan engines, with the greatest improvement stemming from significantly higher cycle pressure ratios. Higher turbine temperature and fan bypass ratios are also expected to contribute to fuel conservation.

  8. MATE program: Erosion resistant compressor airfoil coating, volume 2

    NASA Technical Reports Server (NTRS)

    Freling, Melvin

    1987-01-01

    The performance of candidate erosion resistant airfoil coatings installed in ground tested experimental JT8D and JT9D engines and subjected to cyclic endurance at idle, takeoff and intermediate power conditions has been evaluated. Engine tests were terminated prior to the scheduled 1000 cycles of endurance test due to high cycle fatigue fracture of the Gator-Gard plasma sprayed 88WC-12Co coating on titanium alloy airfoils. Coated steel (AMS5616) and nickel base alloy (Incoloy 901) performed well in both engine tests. Post test airfoil analyses consisted of binocular, scanning electron microscope and metallographic examinations.

  9. Test-engine and inlet performance of an aircraft used for investigating flight effects on fan noise

    NASA Technical Reports Server (NTRS)

    Golub, R. A.; Preisser, J. S.

    1984-01-01

    As part of the NASA Flight Effects on Fan Noise Program, a Grumman OV-1B Mohawk aircraft was modified to carry a modified and instrumented Pratt & Whitney JT15D-1 turbofan engine. Onboard flight data, together with simultaneously measured farfield acoustic data, comprise a flight data base to which JT15D-1 static and wind-tunnel data are compared. The overall objective is to improve the ability to use ground-based facilities for the prediction of flight inlet radiated noise. This report describes the hardware and presents performance results for the research engine.

  10. Interband Phase Modes and Nonequilibrium Soliton Structures in Two-Gap Superconductors

    NASA Astrophysics Data System (ADS)

    Gurevich, A.; Vinokur, V. M.

    2003-01-01

    We predict a new dynamic state in current-carrying superconductors with a multicomponent order parameter. If the current density J exceeds a critical value Jt, an interband breakdown caused by charge imbalance of nonequilibrium quasiparticles occurs. For J>Jt, the electric field penetrating from current leads gives rise to various static and dynamic soliton phase textures, and voltage oscillations similar to the nonstationary Josephson effect. We propose experiments to observe these effects which would probe the multicomponent nature of the superconducting order parameter.

  11. Nacelle Aerodynamic and Inertial Loads (NAIL) project. Appendix B

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The testing was conducted on the Boeing-owned 747 RA001 test bed airplane during the concurrent 767/JT9D-7R4 engine development program. Following a functional check flight conducted from Boeing Field International (BFI) on 3 October 1980, the airplane and test personnel were ferried to Valley Industrial Park (GSG) near Glasgow, Montana, on 7 October 1980. The combined NAL and 7670JT9D-7R4 test flights were conducted at the Glasgow remote test site, and the airplane was returned to Seattle on 26 October 1980.

  12. Improved components for engine fuel savings

    NASA Technical Reports Server (NTRS)

    Antl, R. J.; Mcaulay, J. E.

    1980-01-01

    The Engine Component Improvement (ECI) Project formulated to address near term improvements for current engines is described with emphasis on the development of component technologies to reduce the fuel consumption of CF6, JT9D, and JT8D engines. The technical and economical acceptability and the fuel saving potential of nine concepts are demonstrated. Descriptions of these concepts, results of testing, and the status as to entering airline service are presented. Also presented is the status of the remaining concepts still under development.

  13. Spring-Loaded Joule-Thomson Valve

    NASA Technical Reports Server (NTRS)

    Jones, J. A.; Britcliffe, M. J.

    1986-01-01

    Improved design reduces clogging and maintains constant pressure drop as flow rate varies. Spring-Loaded Joule-Thomson Valve pressure drop regulated by spring pushing stainless-steel ball against soft brass seat. Pressure drop remains nearly constant, regardless of helium flow rate and of any gas contaminants frozen on valve seat. Because springloaded J-T valve maintains constant pressure drop, upstream roomtemperature throttle valve adjusts flow rate precisely for any given upstream pressure. In addition, new valve relatively invulnerable to frozen gas contaminants, which clog fixed-orifice J-T valves.

  14. Local structure of La1-xSrxCoO3 determined from EXAFS and neutron PDF studies

    SciTech Connect

    Proffen, Thomas; Sundaram, Nalini; Jiang, Y; Anderson, Ingrid; Belanger, D P; Booth, C H; Bridges, F; Mitchell, J F; Zheng, H

    2008-01-01

    The combined local structure techniques, extended X-ray absorption fine struture (EXAFS) and neutron pair distribution function (PDF) analysis, have been used for temperatures 4 {<=} T {<=} 330 K to rule out a large Jahn-Teller (J-T) distortion of the Co-O bond in La{sub 1-x}Sr{sub x}CoO{sub 3} for a significant fraction of Co sites (x {<=} 0.35), indicating few, if any, J-T active, single-occupied e{sub g} Co sites exist.

  15. Analysis of turbofan engine performance deterioration and proposed follow-on tests

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.; Kruckenberg, H. D.; Toomey, E. H.

    1975-01-01

    Data and engine parts on in-service JT3D and JT8D engines were analyzed and documented relative to engine deterioration. It is concluded that the fan-compressor system of these engines contributes to the long term engine deterioration. An engine test and instrumentation plan was formulated for a proposed follow-on program. The goal of this program is to verify the above conclusion and to attempt to identify more precisely which components of the fan-compressor system are at fault.

  16. Jahn-Teller distortion of neutral divacancy in Si studied by positron annihilation spectroscopy

    NASA Astrophysics Data System (ADS)

    Nagai, Y.; Inoue, K.; Tang, Z.; Yonenaga, I.; Chiba, T.; Saito, M.; Hasegawa, M.

    2003-12-01

    Jahn-Teller (JT) distortion of the diamagnetic neutral divacancy (V20) in Si is studied by positron annihilation spectroscopy. Based on the anisotropy of electron momentum distribution around the divacancies obtained by two-dimensional angular correlation of positron annihilation radiation (2D-ACAR) technique, the preferred alignment of the divacancy in a specimen by compressing uniaxial stress along the [0 1 1] axis is detected. The direction of the alignment evidences the pairing JT distortion rather than the resonant bonding distortion, which is similar to the distortion in the singly negative divacancy (V2-).

  17. Time Management in Higher Education Administration: A Case Study

    ERIC Educational Resources Information Center

    Lewis, Darrell R.; Dahl, Tor

    1976-01-01

    Drawing on data from a staff development project for administrators in a college at a major American university, it was determined that there is considerable commonality across individuals and that it is possible to deal with such issues as time management, job stress, and enjoyment on an organizational level. (Editor/JT)

  18. Student Suspension and Expulsion Proceedings in Tax Supported Institutions: What Process is Due?

    ERIC Educational Resources Information Center

    Steinberg, Marc I.

    1975-01-01

    Examines the different procedural safeguards which students enjoy in connection with the various disciplinary measures imposed by public school officials: procedural due process rights of students when they are subject to suspensions of up to 10 days, 10 days to three months, more than three months, and expulsions. (JT)

  19. Columbia University Today: Why the Peanut Butter Revolution Didn't Spread

    ERIC Educational Resources Information Center

    Larned, Deborah

    1975-01-01

    A 1970 graduate of Columbia, who was involved in the 1968 student protests, returns to assess the mood of students and the Columbia Corporation (the University as a legal entity) and concludes that students are less militant, possibly because of admissions policies, but that the Columbia Corporation has not changed. (JT)

  20. Photocopy of original drawing showing Wing A (drawing located at ...

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

    Photocopy of original drawing showing Wing A (drawing located at NAWS China Lake, Division of Public Works). J.T. STAFFORD-J.H. DAVIES-H.L. GOGERTY: DISPENSARY, SICK CALL AND ADMINISTRATION, ROOF FRAMING PLAN AND DETAILS - Naval Ordnance Test Station Inyokern, Dispensary, Main Site, Lauritsen Road at McIntyre Street, Ridgecrest, Kern County, CA

  1. Photocopy of original drawing showing Wing A (drawing located at ...

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

    Photocopy of original drawing showing Wing A (drawing located at NAWS China Lake, Division of Public Works). J.T. STAFFORD-J.H. DAVIES- H.L. GOGERTY: DISPENSARY, SICK CALL AND ADMINISTRATION, FLOOR PLAN AND ELEVATIONS - Naval Ordnance Test Station Inyokern, Dispensary, Main Site, Lauritsen Road at McIntyre Street, Ridgecrest, Kern County, CA

  2. Photocopy of original drawing showing Wing E (drawing located at ...

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

    Photocopy of original drawing showing Wing E (drawing located at NAWS China Lake, Division of Public Works). J.T. STAFFORD-J.H. DAVIES-H.L. GOGERTY: SICK OFFICERS QUARTERS, FLOOR PLAN AND ELEVATIONS - Naval Ordnance Test Station Inyokern, Dispensary, Main Site, Lauritsen Road at McIntyre Street, Ridgecrest, Kern County, CA

  3. Photocopy of original drawing showing Building 3 layout (drawing located ...

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

    Photocopy of original drawing showing Building 3 layout (drawing located at NAWS China Lake, Division of Public Works). J.T. STAFFORD-J.H. DAVIES-H.L. GOGERTY: DISPENSARY, CONNECTING CORRIDORS, FLOOR PLAN, ELEVATIONS, AND DETAILS - Naval Ordnance Test Station Inyokern, Dispensary, Main Site, Lauritsen Road at McIntyre Street, Ridgecrest, Kern County, CA

  4. Photocopy of original drawing showing Wing B (drawing located at ...

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

    Photocopy of original drawing showing Wing B (drawing located at NAWS China Lake, Division of Public Works). J.T. STAFFORD-J.H. DAVIES-H.L. GOGERTY: DISPENSARY, SURGICAL AND OBSTETRICAL, FLOOR PLAN AND ELEVATIONS - Naval Ordnance Test Station Inyokern, Dispensary, Main Site, Lauritsen Road at McIntyre Street, Ridgecrest, Kern County, CA

  5. Visual investigation of solid-liquid phase equilibria for nonflammable mixed refrigerant

    NASA Astrophysics Data System (ADS)

    Lee, C.; Yoo, J.; Park, I.; Park, J.; Cha, J.; Jeong, S.

    2015-12-01

    Non-flammable mixed refrigerant (NF-MR) Joule Thomson (J-T) refrigerators have desirable characteristics and wide cooling temperature range compared to those of pure J-T refrigerators. However, the operating challenge due to freezing is a critical issue to construct this refrigerator. In this paper, the solid-liquid phase equilibria (i.e. freezing point) of the NF-MR which is composed of Argon, R14 (CF4), and R218 (C3F8), has been experimentally investigated by a visualized apparatus. Argon, R14 and R218 mixtures are selected to be effectively capable of reaching 100 K in the MR J-T refrigerator system. Freezing points of the mixtures have been measured with the molar compositions from 0.1 to 0.8 for each component. Each test result is simultaneously acquired by a camcorder for visual inspection and temperature measurement during a warming process. Experimental results show that the certain mole fraction of Argon, R14, and R218 mixture can achieve remarkably low freezing temperature even below 77 K. This unusual freezing point depression characteristic of the MR can be a useful information for designing a cryogenic MR J-T refrigerator to reach further down to 77 K.

  6. Union Organizing at Private Colleges and Universities: A Prognosis Revisited

    ERIC Educational Resources Information Center

    Schramm, Carl J.

    1975-01-01

    This analysis of the effects of the National Labor Relations Board jurisdiction over private colleges since 1970 concludes that the employment relationship is not greatly formalized. Organizing is most successful in 2-year institutions with smaller faculties, and the rate of union growth has declined sharply in the last three years. (JT)

  7. 1974-1975 Annual Survey of Labor Relations and Employment Discrimination Law

    ERIC Educational Resources Information Center

    Lombardi, Robert Philip; And Others

    1975-01-01

    Major headings in this review of 1974-75 labor relations and employment discrimination law include Unfair Labor Practices, Arbitration, Seniority, Sex Discrimination, Affirmative Action Under Title VII, Equal Employment Opportunity Commission Enforcement Powers under Section 706, and Federal Employment--Judicial Application of Section 717. (JT)

  8. The Inevitable Interplay of Title VII and the National Labor Relations Act: A New Role for the NLRB

    ERIC Educational Resources Information Center

    University of Pennsylvania Law Review, 1974

    1974-01-01

    The impact of Title VII of the Civil Rights Act of 1964 on seniority and the treatment of employment discrimination under the National Labor Relations Act of 1935 are examined. It is argued that in the area of seniority the National Labor Relations Board (NLRB) has a new role to play in avoiding conflicts between the two acts. (JT)

  9. In Search of Wisdom

    ERIC Educational Resources Information Center

    Vaccaro, Louis C.

    1975-01-01

    Arguing that students' demand for relevance is for wisdom rather than for utilitarian knowledge, and that it is caused by poor teaching, particularly in the liberal arts, the author emphasizes the individual teacher's responsibility to communicate the proper view of education, to lead students in their search for wisdom. (JT)

  10. Teaching by Telephone: Some Practical Observations

    ERIC Educational Resources Information Center

    L'Henry-Evans, Odette

    1974-01-01

    An Open University tutor in the arts describes the experience of conducting conference call tutorials for groups of up to eight students taking a correspondence-type course. Specific techniques are discussed: initial approach designed to make individual students at ease, ways of getting all students involved in dialogue, etc. (JT)

  11. Stroke, tPA, and Physician Decision-Making

    MedlinePlus

    ... of this artery can cause weakness, deficits in sensation, e102 © 2013 American Academy of Neurology ª"NFSJDBO "DBEFNZ PG /FVSPMPHZ 6OBVUIPSJ[FE SFQSPEVDUJPO PG UIJT BSUJDMF JT QSPIJCJUFE impairment of vision, and difficulties with language. Consequently, 70% of respondents believed that a large ...

  12. National Education Trust Fund

    ERIC Educational Resources Information Center

    Shapp, Milton J.

    1975-01-01

    A proposal from the governor of Pennsylvania for financing all levels of education through a National Education Trust Fund (NETF) that would operate as the present Federal Highway Trust Fund does on a revolving, self-liquidating basis with the cost of an individual's education repaid through a progressive education tax on income. (JT)

  13. The Several Ages of Learning

    ERIC Educational Resources Information Center

    Bailey, Stephen

    1976-01-01

    Examines the various stages of human development (as outlined by Erik Erikson and others) with their psychological stresses of recurring crises of identity and expectation and explores some of the implications for education's best serving human needs. Focuses on early childhood, late adolescence, middle age, and old age. (JT)

  14. Community College Dropout Redefined

    ERIC Educational Resources Information Center

    Nickens, John

    1976-01-01

    A study of student attrition rates in 15 Florida junior colleges considered students' educational objectives and plans to reach them. Responses show two groups commonly mislabeled dropouts: those who originally planned to take one or more courses and those who left planning to return. Only two percent were considered legitimate dropouts. (JT)

  15. On the thermal gradient in the Earth's deep interior

    NASA Astrophysics Data System (ADS)

    Tirone, M.

    2015-09-01

    Temperature variations in large portions of the mantle are mainly controlled by the reversible and irreversible transformation of mechanical energy related to pressure and viscous forces into internal energy along with diffusion of heat and chemical reactions. The simplest approach to determine the temperature gradient is to assume that the dynamic process involved is adiabatic and reversible, which means that entropy remains constant in the system. However heat conduction and viscous dissipation during dynamic processes effectively create entropy. The adiabatic and non-adiabatic temperature variation under the influence of a constant or varying gravitational field are discussed in this study from the perspective of the Joule-Thomson (JT) throttling system in relation to the transport equation for change of entropy. The JT model describes a dynamic irreversible process in which entropy in the system increases but enthalpy remains constant (at least in an equipotential gravitational field). A comparison is made between the thermal gradient from the JT model and the thermal gradient from two models, a mantle convection and a plume geodynamic model coupled with thermodynamics including a complete description of the entropy variation. The results show that the difference is relatively small and suggests that thermal structure of the asthenospheric mantle can be well approximated by an isenthalpic model when the formulation includes the effect of the gravitational field. For non-dynamic or parameterized mantle dynamic studies the JT formulation provides a better description of the thermal gradient than the classic isentropic formulation.

  16. On the thermal gradient in the Earth's deep interior

    NASA Astrophysics Data System (ADS)

    Tirone, M.

    2016-02-01

    Temperature variations in large portions of the mantle are mainly controlled by the reversible and irreversible transformation of mechanical energy related to pressure and viscous forces into internal energy along with diffusion of heat and chemical reactions. The simplest approach to determine the temperature gradient is to assume that the dynamic process involved is adiabatic and reversible, which means that entropy remains constant in the system. However, heat conduction and viscous dissipation during dynamic processes effectively create entropy. The adiabatic and non-adiabatic temperature variation under the influence of a constant or varying gravitational field are discussed in this study from the perspective of the Joule-Thomson (JT) throttling system in relation to the transport equation for change of entropy. The JT model describes a dynamic irreversible process in which entropy in the system increases but enthalpy remains constant (at least in an equipotential gravitational field). A comparison is made between the thermal gradient from the JT model and the thermal gradient from two models, a mantle convection and a plume geodynamic model, coupled with thermodynamics including a complete description of the entropy variation. The results show that the difference is relatively small and suggests that thermal structure of the asthenospheric mantle can be well approximated by an isenthalpic model when the formulation includes the effect of the gravitational field. For non-dynamic or parameterized mantle dynamic studies, the JT formulation provides a better description of the thermal gradient than the classic isentropic formulation.

  17. Pseudorotation in fullerene anions

    NASA Astrophysics Data System (ADS)

    Dunn, Janette L.; Hands, Ian D.; Bates, Colin A.

    2007-07-01

    Jahn-Teller (JT) problems are often characterised by an adiabatic potential energy surface (APES) containing either a set of isoenergetic wells or a trough of equivalent-energy points, which may be warped by higher-order coupling terms or anisotropic effects. In all three cases, the JT effect will be dynamic. Either tunnelling between the wells or rotation (of a distortion) around the trough will restore the original symmetry of the system. This motion is referred to as pseudorotation. It should be possible to observe a JT system in a distorted geometry if measurements are made on a sufficiently short timescale. In various cubic systems, this timescale has been calculated to be the order of picoseconds. Such timescales are accessible using modern methods of ultrafast spectroscopy. Measurements of pseudorotation rates can lead to important information on the strength and nature of the JT coupling present. We will present analytical calculations that allow the rate of pseudorotation to be determined in terms of the vibronic coupling parameters. We will show how these results can be applied to E ⊗ e systems and then to the more complicated system applicable to C60- anions. This is of particular interest because of the high icosahedral symmetry of fullerene ions and also because of the many potential uses of materials containing these ions. We conclude by outlining experiments that should be capable of measuring pseudorotation in C 60 anions.

  18. A "Careers in Medicine Seminar" for Secondary School Students

    ERIC Educational Resources Information Center

    Rodgers, Glen E.; And Others

    1976-01-01

    Describes a Thanksgiving weekend seminar for high school students sponsored for the last four years by Muskingum College. Information on careers and educational requirements were presented in lectures, panel and small group discussions, and direct informal contact with practicing professionals and medical educators. (JT)

  19. Design & simulation of in-plane MEMS Lorentz force magnetometer

    NASA Astrophysics Data System (ADS)

    Jyoti, Aditi, Tripathi, C. C.; Gopal, Ram

    2016-03-01

    This report presents the design and simulation of a MEMS based In-plane Lorentz Force Magnetometer (I-LFM), simulated for 8 um UV-LIGA technology using FEM tool of COMSOL Multiphysics 4.3b. Designed I-LFM was simulated in the magnetic field range varied from 1 μJT to 100μJT. The proposed structure composed of a comb drive actuator, configured such that the fingers overlap with each other to generate capacitive coupling for its actuation. The magnetic field can be detected in Z-axis by this comb drive structure. The device was excited by supplying the sinusoidal current with the frequency equivalent to resonance frequency of the device at its first mode i.e. 12.047 kHz. In order to achieve the maximum mechanical output, the device was operated at the resonant frequency. Simulations based results shows a good linearity in the magnetic field range of 1 μJT to 100 μJT with a high quality factor of 130.

  20. An Instrument for the Identification of Core Curriculum in the Discipline of Gynaecology

    ERIC Educational Resources Information Center

    Taylor, P. J.

    1976-01-01

    Describes an instrument designed to identify with considerable agreement appropriate knowledge, skills, and attitudes for gynecology curriculum, relate it to other curriculum content, and determine where it should appear in the curriculum. Focus is on clinical problems to be solved and the underlying processes. (JT)

  1. Perspectives on the Development and Implementation of an Undergraduate General-University Class Dealing with Mind Altering Drugs and Their Use in Today's Society

    ERIC Educational Resources Information Center

    St. Dennis, Clarke D.

    1975-01-01

    A 2-semester hour, no-prerequisite class open to any non-pharmacy major in the university is offered by the Washington State University College of Pharmacy. Course goals, topic outline, results of 1973-74 student course evaluations (mostly positive), and the university course evaluation form are included. (JT)

  2. The Coming Age of People Work

    ERIC Educational Resources Information Center

    Berger, Brigitte

    1976-01-01

    Notes a chasm between cultural and occupational aspirations (for self-realization) and the existing job market. Suggests the opening of a new sector of people work, e.g. services for the very young and very old, urban and community task forces, political participation groups, agencies for intergroup conflict resolution, etc. (JT)

  3. Report of Degrees Conferred by Schools and Colleges of Pharmacy for the Academic Year 1974-1975

    ERIC Educational Resources Information Center

    Rodowskas, Christopher A., Jr.

    1975-01-01

    Statistical tables from the American Association of Colleges of Pharmacy annual survey are presented with some summary commentary. Includes number of male and of female recipients of each degree (BS, BPharm, PharmD, MS, PhD) for each U.S. school. Breakdown by geographical area and by race (by school and by degree) are also presented. (JT)

  4. Characteristics of a liquid-helium-free calibration apparatus for cryogenic thermometers

    NASA Astrophysics Data System (ADS)

    Shimazaki, T.

    2013-09-01

    Closed-cycle Joule-Thomson (JT) cryocoolers have been developed at National Metrology Institute of Japan (NMIJ)/National Institute of Advanced Industrial Science and Technology (AIST) with the aim of realizing a liquid-helium-free calibration apparatus for cryogenic thermometers between 0.65 K and 25 K. The latest JT cryocooler at NMIJ/AIST consists of a 3He JT cooling circuit and a pulse tube mechanical refrigerator. The characteristics of the apparatus including a residual gas analysis of the JT cooling circuit are presented in this paper. Currently the initial cool-down is performed using a heat-exchange gas. It normally takes about 30 h to reduce the temperature from room temperature to 5 K at the thermometer comparison block of the apparatus. The correct timing of the removal of the heatexchange gas is important for the efficient operation of the apparatus. Incomplete removal of the heat-exchange gas induces excess heat load on the apparatus and thermal disturbances. Some examples of abrupt temperature bursts are discussed in this paper. Mechanical refrigerators generate cyclic mechanical vibrations, and precision resistance thermometers are usually very sensitive to a mechanical vibration. The measured vibration level of the developed apparatus is reported. The damage to the apparatus due to the magnitude 9.0 earthquake on March 11, 2011, and possible countermeasures in the case of future earthquakes are also discussed.

  5. Teaching Child Health Problems of Developing Countries to European Medical Students

    ERIC Educational Resources Information Center

    Farquhar, J. W.; And Others

    1976-01-01

    A summary of a symposium presented at the Association of Pediatric Education in Europe. Included are a comparison of child health problems in the developed and undeveloped world, discussion of why Third World child health problems should concern European doctors, and suggested aims, objectives, and curriculum. (JT)

  6. A Preliminary Examination of the In-Training Evaluation Report

    ERIC Educational Resources Information Center

    Skakun, Ernest N.; And Others

    1975-01-01

    The In-Training Evaluation Report (ITER), in use by the Royal College of Physicians and Surgeons of Canada for examining the competencies of candidates eligible for the certifying examination, was tested for validity and reliability. This analysis suggests revisions but declares the ITEA a useful instrument to aid in candidate assessment. (JT)

  7. FIELD MEASUREMENT OF DISSOLVED OXYGEN: A COMPARISON OF METHODS: JOURNAL ARTICLE

    EPA Science Inventory

    NRMRL-ADA- 00160 Wilkin*, R.T., McNeil*, M.S., Adair*, C.J., and Wilson*, J.T. Field Measurement of Dissolved Oxygen: A Comparison of Methods. Ground Water Monitoring and Remediation (Fall):124-132 (2001). EPA/600/J-01/403. The abili...

  8. Part-Time Legal Education: The Kelso Report and More

    ERIC Educational Resources Information Center

    Cox, Michael P.

    1976-01-01

    Observing that historically the American legal teaching profession has strongly objected to part-time legal education, the author traces those attitudes through the ninteenth century to the changes in the 1970s, listing factors contributing to full-time legal education's no longer needing to feel threatened by its part-time sibling. (JT)

  9. Parabolic temporal profiles of non-spanning avalanches and their importance for ferroic switching

    NASA Astrophysics Data System (ADS)

    He, X.; Ding, X.; Sun, J.; Salje, E. K. H.

    2016-02-01

    Computer simulation of a ferroelastic switching process shows avalanche formation with universal averaged temporal avalanche profiles ⟨J(t)⟩, where J(t) is the avalanche "amplitude" at time t. The profiles are derived for the three most commonly used "jerk"-singularities, namely, the total change of the potential energy U via J(t) = (dU(t)/dt)2, the energy drop J(t) = -dU/dt, and the stress drop J(t) = -dτxy/dt. The avalanches follow, within the time resolution of our modeling, a universal profile J(t)/Jmax = 1 - 4(t/tmax - 0.5)2 in the a-thermal regime and the thermal regime. Broadening of the profiles towards a 4th order parabola arises from peak overlap or peak splitting. All profiles are symmetric around t/tmax = 0.5 and are expected to hold for switching processes in ferroic materials when the correlations during the avalanche are elastic in origin. High frequency applications of ferroic switching are constrained by this avalanche noise and its characteristic temporal distribution function will determine the bandwidth of any stored or transmitted signal.

  10. Two-stage, low noise advanced technology fan. 5: Acoustic final report

    NASA Technical Reports Server (NTRS)

    Sofrin, T. G.; Riloff, N., Jr.

    1975-01-01

    The NASA Q2S(quiet two-stage) fan is a 0.836m (32.9 in.) diameter model of the STF 433 engine fan, selected in a 1972 study for an Advanced Technology Transport (ATT) airplane. Noise-control features include: low tip speed, moderate stage pressure rise, large blade-vane spacings, no inlet guide vanes, and optimum blade and vane numbers. Tests were run on the baseline Q2S fan with standard inlet and discharge ducts. Further tests were made of a translating centerbody sonic inlet device and treated discharge ducts. Results were scaled to JT8D and JT3D engine fan size for comparison with current two-stage fans, and were also scaled to STF 433 fan size to compare calculated ATT flyover noise with FAR 36 limits. Baseline Q2S results scaled to JT8D and JT3D engine fan sizes showed substantial noise reductions. Calculated unsuppressed baseline ATT flyovers averaged about 2.5 EPNdB below FAR 36 limits. Using measured sonic inlet results, scaled baseline Q2S fan results, and calculated attenuations for a 1975 technology duct liner, projected flyover noise calculations for the ATT averaged about FAR 36 limits minus 10 EPNdB. Advances in suppression technology required to meet the 1985 goal of FAR 36 limits minus 20 EPNdB are discussed.

  11. ATMOSPHERIC CONCENTRATIONS OF AMMONIA AND AMMONIUM AT AN AGRICULTURAL SITE IN THE SOUTHEAST UNITED STATES: JOURNAL ARTICLE

    EPA Science Inventory

    NRMRL-RTP-P-611 Robarge, W.P., Walker*, J.T., McCulloch, R.B., and Murray, G. Atmospheric Concentrations of Ammonia and Ammonium at an Agricultural Site in the Southeast United States. Atmospheric Environment 36 (10):1661-1674 (2002). 06/18/2001 In this study, we present app...

  12. Jet-cooled laser-induced fluorescence spectroscopy of isopropoxy radical: vibronic analysis of B̃-X̃ and B̃-Ã band systems.

    PubMed

    Chhantyal-Pun, Rabi; Roudjane, Mourad; Melnik, Dmitry G; Miller, Terry A; Liu, Jinjun

    2014-12-26

    Recently we published [ Liu et al. J. Chem. Phys. 2013 , 139 , 154312 ] an analysis of the rotational structure of the B̃-X̃ origin band spectrum of isopropoxy, which confirmed that the double methyl substitution of methoxy to yield the isopropoxy radical only slightly lifted the degeneracy of the former's X̃(2)E state. Additionally the spectral results provided considerable insight into the relativistic and nonrelativistic contributions to the experimental splitting between the components of the (2)E state. However, left unexplained was how the Jahn-Teller (JT) vibronic coupling terms within methoxy's (2)E state manifest themselves as pseudo-Jahn-Teller (pJT) vibronic coupling between the Ã(2)A″ and X̃(2)A' levels of isopropoxy. To cast additional light on this subject we have obtained new isopropoxy spectra and assigned a number of weak, "forbidden" vibronic transitions in the B̃-X̃ spectrum using new electronic structure calculations and rotational contour analyses. The mechanisms that provide the nonzero probability for these transitions shed considerable information on pJT, spin-orbit, and Coriolis coupling between the à and X̃ states. We also report a novel mechanism caused by pJT coupling that yields excitation probability to the B̃ state dependent upon the permanent dipole moments in the B̃ and à or X̃ states. By combining a new B̃-à and the earlier B̃-X̃ rotational analyses we determine a much improved value for the experimental Ã-X̃ separation. PMID:25054866

  13. Is The Modern Lease a Contract or a Conveyance?--A Historical Inquiry

    ERIC Educational Resources Information Center

    Siegel, Stephen A.

    1975-01-01

    Argues that "contrary to conventional wisdom, current landlord-tenant law is modern, commercial, and already grounded in contract doctrine." Discusses the origins of the doctrines most frequently cited as illustrations of leasings property basis and redevelops the role of property law in adjudicating leasing disputes. (JT)

  14. Alexander v. Gardner-Denver: A Threat to Title VII Rights

    ERIC Educational Resources Information Center

    Richards, Richard F.

    1975-01-01

    An examination of the decision on the rights of an employee, who has unsuccessfully pursued a race or sex discrimination claim through arbitration, to "relitigate" the claim under Title VII, Civil Rights Act of 1964. Conclusion: the decision endangers Title VII rights by granting too much weight to prior arbitration awards. (JT)

  15. College Stores 1975--A Challenge to the Publishers

    ERIC Educational Resources Information Center

    Davis, Howard W.

    1976-01-01

    A presentation by the general manager of the Harvard Cooperative Society to the College Division of the Association of American Publishers in which he illustrates with survey data the contention that suggested publishers prices for textbooks are arbitrarily set too low by publishers to cover minimal costs of marketing textbooks. (JT)

  16. Amending the Amendments

    ERIC Educational Resources Information Center

    McNamara, William

    1976-01-01

    Reviews activity in Congress, federal agencies, and higher education associations as legislation to extend and improve the 1972 Higher Education Amendments is being fashioned. Issues include a public vs. private debate regarding use of the Basic Opportunity Grant program (BOG) to foster access as opposed to choice among institutions. (JT)

  17. 77 FR 16916 - Airworthiness Directives; Pratt & Whitney (PW)Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ... NPRM published in the Federal Register on November 23, 2011 (76 FR 72348). That NPRM proposed to... Written The Boeing Company and an individual commenter support the NPRM (76 FR 72348, November 23, 2011... engine models. We agree. In addition to the JT9D-7R4G2 and -7R4H1 engines, the NPRM (76 FR...

  18. University Counselor: Lore, Logic and Logistics

    ERIC Educational Resources Information Center

    Sensenbrenner, Richard J.

    1974-01-01

    Suggestions of ways university counsel can serve the client better with greater hourly productivity. Lists advantages of attorneys working from one office and under the president (not the board), describes some systems for recordkeeping (docketing, citation file, policy orders, etc.), and outlines an approach to preventive law. (JT)

  19. Challenges to Legitimacy: Dilemmas and Directions

    ERIC Educational Resources Information Center

    Yarmolinsky, Adam

    1976-01-01

    Three options are discussed for institutional responses to pressures from clients (students), competitors, taxpayers, citizen activists, and faculty: (1) to concentrate on the preservation of traditional values; (2) to maximize growth in new markets; or (3) to seek a new educational synthesis. (JT)

  20. Hoods for Science Laboratories.

    ERIC Educational Resources Information Center

    Horowitz, Harold; and others

    Detailed discussions are presented dealing with the selection and design of fume hoods for science laboratories. Areas covered include--(1) air flow design, (2) materials properties, (3) location in the laboratory, (4) testing and adjustment, (5) exhaust systems, and (6) hazards of fume discharges. (JT)

  1. Preliminary design study of astronomical detector cooling system

    NASA Technical Reports Server (NTRS)

    Norman, R. H.

    1976-01-01

    The preliminary design of an astronomical detector cooling system for possible use in the NASA C-141 Airborne Infrared Observatory is presented. The system consists of the following elements: supercritical helium tank, Joule-Thomson supply gas conditioner, Joule-Thomson expander (JTX), optical cavity dewar, optical cavity temperature controller, adjustable J-T discharge gas pressure controller, and vacuum pump.

  2. International Education: An Agenda for Global Interdependence

    ERIC Educational Resources Information Center

    Bailey, Stephen K.

    1975-01-01

    In light of the need for national leaders informed in international affairs and for informed citizenry capable of supporting and questioning the experts, responses from various quarters to the need for international education are found to be substantial but shy of the obvious and growing need. (JT)

  3. An Approach to Assessing Pharmacy Student Competency Development

    ERIC Educational Resources Information Center

    Popovich, Nicholas G.; Martin, F. Gene

    1975-01-01

    Research demonstrated that competency development of senior pharmacy students could be quantified by a series of examinations, which showed that in the last professional year student performance and ability with pharmacy information and knowledge approached and eventually equalled that of registered pharmacists. (JT)

  4. Relationships of physical job tasks and living conditions with occupational injuries in coal miners.

    PubMed

    Bhattacherjee, Ashis; Bertrand, Jean-Pierre; Meyer, Jean-Pierre; Benamghar, Lahoucine; Otero Sierra, Carmen; Michaely, Jean-Pierre; Ghosh, Apurna Kumar; d'Houtaud, Alphonse; Mur, Jean-Marie; Chau, Nearkasen

    2007-04-01

    This study assessed the relationships of job tasks and living conditions with occupational injuries among coal miners. The sample included randomly selected 516 underground workers. They completed a standardized self-administred questionnaire. The data were analyzed via logistic regression method. The rate of injuries in the past two years was 29.8%. The job tasks with significant crude relative risks were: power hammer, vibrating hand tools, pneumatic tools, bent trunk, awkward work posture, heat, standing about and walking, job tasks for trunk and upper/lower limbs, pain caused by work, and muscular tiredness. Logistic model shows a strong relationship between the number of job tasks (JT) and injuries (adjusted ORs vs. JT 0-1: 2.21, 95%CI 1.27-3.86 for JT 2-6 and 3.82, 2.14-6.82 for JT>or=7), and significant ORs>or=1.71 for face work, not-good-health-status, and psychotropic drug use. Musculoskeletal disorders and certain personality traits were also significant in univariate analysis. Therefore job tasks and living conditions strongly increase the injuries, and occupational physicians could help workers to find remedial measures. PMID:17485883

  5. I Learn You: Accountability at the Academy

    ERIC Educational Resources Information Center

    Dennis, Lawrence J.

    1975-01-01

    An attack on the concept of educational accountability, arguing that teaching is not amenable to cost accounting and that the management concept of accountability, illogically applied to education, which is unproductive in a tangible sense, is a tyrany potentially damanging to society. (JT)

  6. Production of Artificial Lightning in An Ordinary Clear Light Bulb.

    ERIC Educational Resources Information Center

    Zaffo, Peter Alfred

    1981-01-01

    Reported is a method of producing artificial lightning in an ordinary clear lightbulb. The appearance of sparks produced is that of a miniature stroke of forked lightning seen in natural thunderstorms. The sparks also show the intricate branching patterns often seen in natural lightning. (JT)

  7. Leadership Training

    ERIC Educational Resources Information Center

    Kaye, Beverly L.; Scheele, Adele M.

    1975-01-01

    A survey of 60 programs to prepare women for leadership in business and education identifies two distinct types of skills training (lifebuilding skills and technical and managerial skills) and offers ideas to institutions planning leadership programs. Six model programs are described and 24 are listed in the bibliography. (Editor/JT)

  8. Pregnancy and Sex-Based Discrimination in Employment: A Post-Aiello Analysis

    ERIC Educational Resources Information Center

    Levine, Joanne L.

    1975-01-01

    Assesses the effect of the Supreme Court decision, Geduldig v. Aiello, on the interpretative guidelines of the Equal Employment Opportunity Commission (EEOC), which in enforcing Title VII of the Civil Rights Act treats pregnancy like any other temporary disability. Concludes that the Court should give "great deference" to the EEOC guidelines. (JT)

  9. Equal Employment + Equal Pay = Multiple Problems for Colleges and Universities

    ERIC Educational Resources Information Center

    Steinbach, Sheldon Elliot; Reback, Joyce E.

    1974-01-01

    Issues involved in government regulation of university employment practices are discussed: confidentiality of records, pregnancy as a disability, alleged discrimination in benefits, tests and other employment criteria, seniority and layoff, reverse discrimination, use of statistics for determination of discrimination, and the Equal Pay Act. (JT)

  10. Sex Discrimination as to Maternity Benefits

    ERIC Educational Resources Information Center

    Larson, Arthur

    1975-01-01

    A general survey of the state of the law at all points where maternity produces a claim of sex discrimination in employment and discussion of whether, under Geduldig v. Aiello, all private fringe benefit systems must equate normal pregnancy with temporary sickness and disability. (JT)

  11. Doctor-Patient Communication in General Practice Consultations

    ERIC Educational Resources Information Center

    Bain, D. J. G.

    1976-01-01

    Analysis of categories of verbal interaction in a series of tape-recorded doctor-patient interviews enabled the author to perform a critical self-audit of his consultations. He suggests the methods could be employed with advantage in the fields of undergraduate and postgraduate teaching. (JT)

  12. The Radcliffe Institute: Is There Life After Birth?

    ERIC Educational Resources Information Center

    Stent, Angela

    1975-01-01

    Purposes and program of the Radcliffe Institute are described from its creation in 1960 as "one effort to change the social climate for women" by offering part-time fellowships so that talented women might again become "visible professionally" to its present increasingly professional orientation. (JT)

  13. Assessing Competence in Pediatric Cardiology

    ERIC Educational Resources Information Center

    Johnson, Apul E.; And Others

    1976-01-01

    In response to the need to assure physician competence, a rating scale was developed at the University of Minnesota Medical School for use in evaluating clinical competence in pediatric cardiology. It was tested on first- and second-year specialists. Development and testing procedures are described. (JT)

  14. Death of a College

    ERIC Educational Resources Information Center

    Wood, Herbert H.

    1975-01-01

    Contending that when a college fails it is the governing board that holds final responsibility, the author points out the early warning signals and most frequent mistakes and lists eight rules for survival. Emphasis is on the need to consider more seriously the long-range consequences of decisions. (JT)

  15. The Perfect Politician

    ERIC Educational Resources Information Center

    Berry, John N., III

    2010-01-01

    The perfect politician, the ideal political ally to a library, is often but not always an elected official. He or she is always an effective champion of "reasonable financial support," i.e., "the amount...which a thoroughly competent librarian can spend wisely." That is what J.T. Wyer, director of the New York State Library, said in his "What the

  16. Adelphi on Wheels

    ERIC Educational Resources Information Center

    Levy, Lawrence C.

    1976-01-01

    Adelphi University has awarded 76 Masters in Business Administration degrees to people in the New York City area who attended its Classroom on Wheels, one specially equipped car on each of four commuter train lines. The program, reaching over 1000 people since 1971 is run and promoted solely on tuition. (JT)

  17. Reflections on Educational Capitalism

    ERIC Educational Resources Information Center

    Kenny, Philip W.

    1975-01-01

    The author observes that when, as now, there are more college seats available than students to fill them, the schools respond to the market and not to true educational needs or to school philosophy. He argues that practices appropriate in commerce are harmful in education and calls for planning and controlled growth. (JT)

  18. Sex-Role Stereotyping and Social Work Education

    ERIC Educational Resources Information Center

    Diangson, Pat; And Others

    1975-01-01

    The influence of social work education on the sex distribution in social work practice was examined for students at the University of Wisconsin, Madison, where there is no formal tracking into casework, groupwork, and community organization. It is concluded that policy and curriculum changes can alter traditional sex-role stereotypes. (JT)

  19. The Corporate Law Curriculum

    ERIC Educational Resources Information Center

    Mofsky, James S.

    1976-01-01

    On the premise that corporate counsel must be an able diagnostician before he can focus on highly specialized and interrelated issues of business law, the author suggests an approach to corporate law curriculum in which the basic course balances the quality and quantity of material designed to create the needed sensitivity. (JT)

  20. An Alternative to Anesthetic Learning Climates

    ERIC Educational Resources Information Center

    Epperson, David C.

    1975-01-01

    On the premise that the college classroom should heighten, not cool, a zeal for learning, the author proposes that colleges extend the range of alternative paths to personal growth through a program of voluntary temporary learning communities using diverse modes of inquiry. (JT)

  1. Predictors of Academic Success in Medical School

    ERIC Educational Resources Information Center

    Davis, G. Lindsey; And Others

    1976-01-01

    A study of the predictive validity of selected admissions variables used by the University of Kentucky College of Medicine (Medical College Admissions Test subscores, undergraduate science grade point average (USGA), age, and Otis Test of Mental Ability) revealed the predictive validity of USGA and the MCAT quantitative subscore. (JT)

  2. 14 CFR 34.1 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... airplane as defined in 14 CFR part 1 for which a U.S. standard airworthiness certificate or equivalent... otherwise would have been fulfilled by turbojet and turbofan engines except engines of class T3, T8, and TSS. Class T3 means all aircraft gas turbine engines of the JT3D model family. Class T8 means all...

  3. Dental Topics for Medical Students

    ERIC Educational Resources Information Center

    Lorber, Mortimer

    1976-01-01

    As part of the required Introduction to Clinical Sciences course, second-year students at Georgetown University School of Medicine attend three one-hour lectures on dentistry: restorative dentistry, oral surgery, and various diseases. Contents of the lectures are summarized here. (JT)

  4. Interaction of Sex and Year of Enrollment in Student Perceptions of the University Climate

    ERIC Educational Resources Information Center

    Pascarella, Ernest T.

    1976-01-01

    Freshmen at two institutions sampled had significantly higher ratings of the climate on an intellectualism/scholarship factor than seniors. As length of exposure to the institution increased (comparing freshmen with seniors) assessments of the environmental press by male and female students tended to diverge. (Editor/JT)

  5. Interview: Public Alternative Schools in Eugene, Oregon

    ERIC Educational Resources Information Center

    Edcentric, 1976

    1976-01-01

    Information from interviews with a parent coordinator at Eastside Elementary School, a teacher at Silver Lea Corridor School, and a student at Action High and the Planning Course is presented to show history, relationship and function with parents, teachers, students, and administrators in the Eugene, Oregon, public alternative school system. (JT)

  6. Academic Freedom in South Africa: The Open Universities in South Africa and Academic Freedom, 1957-1974

    ERIC Educational Resources Information Center

    Minerva, 1975

    1975-01-01

    When the South African government initiated a racial separation policy in universities in 1957 the Universities of Cape Town and Witwatersrand, Johannesburg, declared their opposition and continue after 17 years to pursue their efforts for racial equality. This report assesses the effects on university structure and academic freedom. (JT)

  7. Employee Selection at the University of Houston Libraries

    ERIC Educational Resources Information Center

    Brand, Marvine

    1975-01-01

    The development and operation of a successful employee selection, promotion, and transfer program is described. The 3-year program involved posting public notices of all library vacancies, actual or anticipated, and encouraging individuals, whether on the staff or not, to apply for positions in which they were interested. (JT)

  8. HOW TO PROVIDE AUTOMATIC FIRE PROTECTION FOR YOUR BUILDING.

    ERIC Educational Resources Information Center

    Honeywell, Inc., Minneapolis, Minn.

    THE ADVANTAGES OF PROMPT FIRE DETECTION IS DISCUSSED WITH RESPECT TO THE NATURE AND COST OF FIRES. EQUIPMENT IS DESCRIBED, AND DIAGRAMS OF INSTALLATIONS OF DETECTION AND ALARM SYSTEMS ARE GIVEN FOR SCHOOLS, HOSPITALS, COMMERICAL BUILDINGS, INDUSTRIAL PLANTS, AND CAMPUSES. (JT)

  9. Education for Becoming: Two Field Programs at Antioch

    ERIC Educational Resources Information Center

    Kelly, Michael; Prier, Linda

    1974-01-01

    Based on the premise that therapy is a way of learning, two Field Centers were developed: (1) a small group in New Mexico who studied geology, botany, wilderness survival skills and themselves, the latter using group dream study methods and (2) a group in Switzerland to study Jungian psychology including individual analysis. (JT)

  10. Cluster of Infections Caused by Methicillin-Resistant Staphylococcus pseudintermedius in Humans in a Tertiary Hospital

    PubMed Central

    Börjesson, Stefan; Grönlund-Andersson, Ulrika; Tellgren-Roth, Christian; Melhus, Åsa

    2014-01-01

    The dog-associated Staphylococcus pseudintermedius is a rare pathogen in humans. Here we describe a cluster of infections caused by the methicillin-resistant S. pseudintermedius clone ST71-J-t02-II–III. It involved four elderly patients at a tertiary hospital. Three patients had wound infections, and the strain had a tendency to cause bullous skin lesions. PMID:24871217

  11. The Code of Professional Responsibility and the College and University Lawyer

    ERIC Educational Resources Information Center

    Williams, Omer S. J.

    1975-01-01

    Background and history of the Canons of Ethics and Code of Professional Responsibility, adopted by the American Bar Association in 1969, are briefly outlined, and, as a case study, certain contexts in which ethical questions may arise for the college or university lawyer are discussed. Focus is on the lawyer as advisor. (JT)

  12. Teaching of Formal Courses by Medical Librarians

    ERIC Educational Resources Information Center

    Martin, Jess A.; And Others

    1975-01-01

    Four courses on the use of the library are described which were taught by librarians at the University of Tennessee Center for Health Services to graduate students in basic medical sciences, dentistry, and pharmacy and undergraduates in medical records administration. Also included is a survey of medical libraries offering such courses. (JT)

  13. A Couples Group of Medical Students

    ERIC Educational Resources Information Center

    Porter, Kenneth; And Others

    1976-01-01

    An experiment at the Albert Einstein College of Medicine with a short-term medical student couples' workshop designed to foster increased sensitivity between medical students and their partners resulted in recommendation that such workshops be offered to medical students. (JT)

  14. A Marketing Plan That Works

    ERIC Educational Resources Information Center

    Sparks, Jack D.

    1976-01-01

    Olivet College's marketing plan included survey of students, alumni, townspeople, and doners and analysis of the college's customer appeal, prices, and product mix. The author reports that the marketing objectives are being met and discusses the rationale and problems of applying business marketing principles to education. (JT)

  15. The Timing of Student Examinations

    ERIC Educational Resources Information Center

    Dugdale, Alan E.

    1975-01-01

    Proposes a plan by which medical students could take a final examination 80 percent of the way through a course, allowing students to learn in their own way with more efficient use of teacher time and less stress of terminal exams because all students would have two chances without penalty. (JT)

  16. The Place of Colleague Evaluation in the Appraisal of College Teaching: A Review of the Literature

    ERIC Educational Resources Information Center

    Batista, Enrique E.

    1976-01-01

    Little agreement as to criteria for evaluating college teaching was found in a literature review. A list of 10 activities and faculty behaviors that can be more reliably and validly evaluated by fellow colleagues than by students or administrators is presented. Recommendations for upgrading colleague evaluation of teaching are made. (JT)

  17. Integration host factor is required for replication of pYGK-derived plasmids in Aggregatibacter actinomycetemcomitans.

    PubMed

    Torres-Escobar, Ascención; Juárez-Rodríguez, María D; Demuth, Donald R

    2014-08-01

    In this study, we show that integration host factor protein (IHF) is required for replication of pYGK plasmids in Aggregatibacter actinomycetemcomitans. YGK plasmids were not replicated in A. actinomycetemcomitans strains lacking either the α- or β- subunit of IHF. However, the deletion mutants were complemented, and plasmid replication was restored when the promoter region and gene for either ihfA or ihfB was cloned into pYGK. We also identified two motifs that resemble the consensus IHF-binding site in a 813-bp fragment containing the pYGK origin of replication. Using electrophoretic mobility shift assays, purified IHFα-IHFβ protein complex was shown to bind to probes containing either of these motifs. To our knowledge, this is the first report showing that plasmid replication is IHF-dependent in the family Pasteurellaceae. In addition, using site-direct mutagenesis, the XbaI and KpnI restriction sites in the suicide vector pJT1 were modified to generate plasmid pJT10. The introduction of these new unique sites in pJT10 facilitates the transfer of transcriptional or translational lacZ fusion constructs for the generation of single-copy chromosomal insertion of the reporter construct. Plasmid pJT10 and its derivatives will be useful for genetic studies in Aggregatibacter (Actinobacillus) and probably other genera of Pasteurellaceae, including Haemophilus, Pasteurella, and Mannheimia. PMID:24965736

  18. School Learning and Adjustment: Interdisciplinary Training for Pediatricians

    ERIC Educational Resources Information Center

    Rockowitz, Ruth J.; Stebbins, Winifred

    1975-01-01

    Describes and evaluates the School Health Programs of the University of Rochester School of Medicine and Dentistry's pediatric training: first-year lectures, second-year electives, clinical consultation for house officers, and a year-long experience as a local school consulting pediatrician for associate residents and fellows. (JT)

  19. Integrating Content on Feminism and Racism into the Social Work Curriculum

    ERIC Educational Resources Information Center

    Loewenstein, Sophie F.

    1976-01-01

    It is suggested that power relationships among people have become a unifying concept of human behavior in modern society, replacing the Freudian libido, and that this concept can function as a unifying principle for integrating racism, sexism and other key relationship concerns into the human behavior curriculum sequence. (Editor/JT)

  20. Military Law--Stepchild of Legal Education

    ERIC Educational Resources Information Center

    Douglass, John Jay

    1974-01-01

    Examines the scope of modern military law and its special characteristics, identifies clientele and membership of the military bar, and reviews civilian and military educational programs in military law with special attention to that of the U.S. Army Judge Advocate General's School. (JT)

  1. The Reverend Thomas Jefferson Bowen: An Introductory Background to His Linguistic Works, 1850-1856

    ERIC Educational Resources Information Center

    Awoniyi, Timothy A.

    1974-01-01

    A historical narrative background for the linguistic works of Thomas Jefferson Bowen, an American missionary who was the first non-Nigerian to publish a grammar of Yoruba (1858). The author points up a need for further scholarly review of Bowen's pioneering work and contribution to Yoruba studies. (JT)

  2. The Coagulation Method of Starting Lecture-Discussion Courses

    ERIC Educational Resources Information Center

    Nyberg, David

    1976-01-01

    Describes a method used in the first class periods of a foundations of education course of 20-35 students to introduce students to each other and develop the interpersonal climate necessary for an effective discussion course. Involves breaking up into groups of five strangers for personal introductions and later class presentations. (JT)

  3. Conflicts of Law; An Appeal for Revival of Its Multinational Character

    ERIC Educational Resources Information Center

    Carl, Beverly May

    1974-01-01

    Contains an annotated outline intended to assist law professors who may wish to incorporate international material in their regular conflicts courses as a summary lecture, a full semester course in private international law, or interwoven with the pertinent section on American law. (JT)

  4. Impurity control and heat removal from core plasma

    SciTech Connect

    Fujisawa, N.; Hamada, Y.; Shimomura, Y.

    1983-12-01

    Jaeri and the Institute of Plasma Physics review the issues of heat and particle removal from core-plasma and related impurity control issues. The representative concepts of impurity-control systems for the DIVA/JET-2a, Doublet-III, JT-60, R-Tokamak, and Fusion Experimental Reactor (FER) tokamaks are described.

  5. Financial Aid Reports: Loans to Parents, New Help for the Middle-Income Family

    ERIC Educational Resources Information Center

    Bowman, James L.; Johnstone, D. Bruce

    1975-01-01

    Addresses the need for a national parental loan program proposing that loans up to the amount of the total expected contribution less that portion which can reasonably be expected out of current disposable purchasing power be offered as part of a total financial assistance package. (JT)

  6. Evaluation of Instructional Methods for Teaching Veterinary Students the Components of Inflammation

    ERIC Educational Resources Information Center

    Fletcher, O. J.; Welser, J. R.

    1975-01-01

    Seven multi-media instructional programs were evaluated on the basis of test scores, student attitudes, program preparation time, and cost of materials. Programs ranked best were videotape with 35mm slides, programmed instruction with 35mm slides, and Self-Evaluation Test only. (JT)

  7. Pure Mathematics in Australia

    ERIC Educational Resources Information Center

    Bloom, W. R.; And Others

    1975-01-01

    Reports a survey concerned with the future of mathematics in Australia which identified the number of "experts" in particular areas of mathematics who are working in Australia. Findings show increased research work in the past five years but conclusions indicate that many mathematical areas continue to be neglected. (JT)

  8. Operational Management of Area Environment.

    ERIC Educational Resources Information Center

    Sprague, George W.

    Three phases leading to the automation of the mechanical building systems on the Harvard campus are described. The systems allow a single operator to monitor and control all the mechanical systems, plus fire, flood, and security alarms, for all buildings in a large area of the campus. (JT)

  9. Hair tonic poisoning

    MedlinePlus

    Finnell, JT. Alcohol-related disease. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 185. Zosel AE. General approach to the poisoned patient. ...

  10. Hangover treatment

    MedlinePlus

    Finnell JT. Alcohol-related disease. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 185. O'Connor PG. Alcohol use disorders. In: Goldman ...

  11. Student Attrition in North American Veterinary Schools

    ERIC Educational Resources Information Center

    Hooper, Billy E.; Brown, Roger E.

    1975-01-01

    Data presented shows a progressive reduction in North American veterinary student attrition from 12.8 percent in 1966 to 3.1 percent in 1974. The prediction is that with improved selection procedures and time-variable instructional programs the rate will drop and stabilize at approximately two percent. (JT)

  12. Applicability of the Joule-Thomson Cryocooler Coupled with Membrane-Based Purification System for Liquefaction of Natural Gas in Small Quantities

    NASA Astrophysics Data System (ADS)

    Piotrowska, A.; Chorowski, M.

    2008-03-01

    Joule-Thomson (J-T) cryocoolers using gas mixture have been studied theoretically and experimentally for a variety of applications. Gas separation technology using polymer membrane is emerging. In this paper the concept of coupling the J-T cooler with a hollow fiber membranes is presented. The apparatus can be used in many applications, like compressed natural gas (CNG) purification and condensation into LNG or separation and liquefaction of nitrogen from air. The paper describes the system and experimental dependence of the separated nitrogen purity on the membrane inlet air pressure. The Second Law of Thermodynamics is used to optimize the composition of the mixture for natural gas cooling and liquefaction. Possible applications of the system depend on membrane material. Membranes used in separation of N2/air or CO2/CH4 are now commercially available [2,6]. The combination of the J-T cooler with N2/air membrane enables the construction of the liquid nitrogen production system aimed at cryosurgical applications. Similarly, J-T cooler coupled with CO2/CH4 membrane can be used for purification and liquefaction of natural gas in small quantities e.g. satisfying future car refueling system needs.

  13. A Novel Mutation in a Patient with Hyperparathyroidism-Jaw Tumour Syndrome.

    PubMed

    Bellido, Virginia; Larrañaga, Ihintza; Guimón, Maite; Martinez-Conde, Rafael; Eguia, Asier; Perez de Nanclares, Gustavo; Castaño, Luis; Gaztambide, Sonia

    2016-06-01

    Hyperparathyroidism-jaw tumour syndrome (HPT-JT) is a rare variant of familial hyperparathyroidism, characterized by primary hyperparathyroidism (PHPT) due to one or multiple parathyroid adenomas, and benign tumours of the mandible and maxilla. It has an autosomal dominant pattern of inheritance, and is associated with mutations that deactivate the cell division cycle protein 73 homolog (CDC73) gene, also known as hyperparathyroidism 2 (HRPT2), located on the long arm of chromosome 1, that encodes for the tumour suppressor protein parafibromin. In the majority of cases, PHPT is the presenting symptom, but up to 30 % of HPT-JT cases initially present with an ossifying fibroma of the maxillofacial bones. HPT-JT may result in severe hypercalcemia-related complications and an elevated risk of parathyroid carcinoma. For this reason, early identification of the disease is important. We present the case of a 23-year-old woman who was found to have jaw tumours and was later diagnosed with PHPT. Genetic analysis revealed a novel mutation in exon 1 of CDC73. This report contributes to the understanding of the genetics of this rare syndrome. It also highlights the fact that HPT-JT should be considered and CDC73 mutation analysis should be performed in cases of early-onset PHPT associated with ossifying fibromas of the jaw. PMID:26995009

  14. Extended region of nodulation genes in Rhizobium meliloti 1021. I. Phenotypes of Tn5 insertion mutants

    SciTech Connect

    Swanson, J.A.; Tu, J.K.; Ogawa, J.; Sanga, R.; Fisher, R.F.; Long, S.R.

    1987-10-01

    Rhizobium meliloti Nod/sup -/ mutant WL131, a derivative of wild-type strain 102F51, was complemented by a clone bank of wild-type R. meliloti 1021 DNA, and clone pRmJT5 was recovered. Transfer of pRmJT5 conferred alfalfa nodulation on other Rhizobium species, indicating a role in host range determination for pRmJT5. Mutagenesis of pRmJT5 revealed several segments in which transposon insertion causes delay in nodulation, and/or marked reduction of the number of nodules formed on host alfalfa plants. The set of mutants indicated five regions in which nod genes are located; one mutant, nod-216, is located in a region not previously reported to encode a nodulation gene. Other mutant phenotypes correlated with the positions of open reading frames for nodH, nodF and nodE, and with a 2.2-kb EcoRI fragment. A mutant in nodG had no altered phenotype in this strain. One nodulation mutant was shown to be a large deletion of the common nod gene region. The authors present a discussion comparing the various studies made on this extended nod gene region.

  15. The Effects of Inflation/Recession on Higher Education

    ERIC Educational Resources Information Center

    Bowen, William G.

    1975-01-01

    While costs are increasing and revenues from endowment earnings and gifts decreasing, private and public institutions are being forced to cut spending. The author outlines a national program of competitive fellowship awards designed to help meet these problems and to sustain the quality of higher education. (Editor/JT)

  16. Constitutional and Statutory Regulation of Private Colleges and Universities

    ERIC Educational Resources Information Center

    Faccenda, Philip J.

    1975-01-01

    Considers the main thrust of recent increases in judicial and administrative review of the internal policies of colleges and universities, pointing out exceptions presently applicable to private institutions. Conclusion: Private colleges would be well advised to comply voluntarily with laws which admittedly apply only to public institutions. (JT)

  17. NATURAL BIODEGRADATION OF NTBE ON A SITE ON LONG ISLAND, NY: SYMPOSIUM

    EPA Science Inventory

    NRMRL-ADA-00170 Kolhatkar, R., Wilson*, J.T., and Hinshalwood, G. "Natural Biodegradation of NTBE on a Site on Long Island, NY." In: 6th Intl. In-Situ and On-Site Symposium on Bioremediation of MTBE, Alcohols, and Ethers, Battelle, The Si...

  18. Educational Opportunities in "Law and Medicine" in Law Schools

    ERIC Educational Resources Information Center

    Hirsh, Harold L.

    1975-01-01

    Noting the rapid expansion of forensic or legal medicine the author reports a survey conducted to determine the medical-legal education opportunities in American law schools. Findings showed that in 73 percent of the schools courses in law and medicine or forensic psychiatry are offered but many are limited in scope. (JT)

  19. Some Legal Aspects of Veterinary College Admission Requirements

    ERIC Educational Resources Information Center

    Hannah, H. W.

    1975-01-01

    Examines admissions requirement problems regarding the legality of using criteria related to professional performance but which are less capable of evaluation than academic standing; of considering race or sex as factors; of either more or less stringent requirements for non-residents of the state. (JT)

  20. Interprofessional Legal Practitioners: The Case of the M.D.-LL.B.

    ERIC Educational Resources Information Center

    Schneller, Eugene Stewart

    1975-01-01

    Careers and problems encountered by the large majority of M.D.-LL.B's who practice legal medicine are examined. The author argues that the legal profession must strive to create institutionalized career lines so that interprofessional medical-legal practice is a well-founded career choice. (JT)

  1. A Formal Procedure for the Determination of Internship Preferences

    ERIC Educational Resources Information Center

    Grochow, Louise B.; Grochow, Jerrold

    1976-01-01

    The authors describe one way of organizing and formalizing judgements and values so that the senior medical student can prepare a preference list of internship programs that will provide maximum satisfaction to the student when the computer matching program is employed. (JT)

  2. Consumer Perceptions of Health Care Services: Implications for Academic Medicine

    ERIC Educational Resources Information Center

    Ware, John E., Jr.; And Others

    1975-01-01

    Factor analytic development of various measures of consumer perceptions regarding characteristics of doctors and health care services is described. Findings are discussed in relation to program planning and evaluation in medical education, and suggestions for future research are noted. (Editor/JT)

  3. Medical Anthropology in the Curriculum: A Revisit to the Subject

    ERIC Educational Resources Information Center

    Roush, Robert E.; And Others

    1976-01-01

    Although progress has been made in the last 15 years in the development of medical school departments with interests in the various behavioral science fields, including anthropology, based on this study only five percent of U.S. medical students had the opportunity to attend lectures in the field of medical anthropology. (Editor/JT)

  4. Programmed Student Achievement: A Hawthorne Effect?

    ERIC Educational Resources Information Center

    Haddad, Nabil F.; And Others

    1975-01-01

    Three groups of college students were given instructions using different testing techniques to determine whether the superior performance obtained with Programed Student Achievement (PA) was due to a Hawthorne Effect. Results seem to preclude any attempt to interpret the effectiveness of PA on that basis. (Editor/JT)

  5. Social Work in the Police Agency: Implications for Education and Practice

    ERIC Educational Resources Information Center

    Treger, Harvey

    1976-01-01

    Issues uncovered in a 3-year action-research project that placed social workers and graduate students in community police departments were selection of staff and students, attitudes about the law, confidentiality, motivating the reluctant client, and sensitivity to police-social worker perceptions of each other. (JT)

  6. Some Effects of Ph.D. Training on the Academic Labour Markets of Australian and British Universities

    ERIC Educational Resources Information Center

    Davis, Denis J.

    1976-01-01

    The background of Ph.D.s is tabulated to show the loss to the stock of university manpower of non-academic but educationally valuable experience through growing competition for jobs by Ph.D.s. The conclusion is that forces causing the Ph.D. displacement of labour in the university academic labour market should be constrained. (Editor/JT)

  7. Constitutional Law--Equal Protection--"Benign" Discrimination--Minority Admissions Programs--Supreme Court's Response to Preferential Treatment--DeFunis v. Odegaard, 416 U.S. 312 (1974); Kahn v. Shevin, 416 U.S. 351 (1974); Morton v. Mancari, 417 U.S. 535 (1974)

    ERIC Educational Resources Information Center

    Bloom, Judith Ilene

    1975-01-01

    Three U.S. Supreme Court rulings on minority preference cases are analyzed with reference to the question of the constitutionality of minority preferential admissions. It is concluded that the Court's unpredictability casts doubt on the validity of minority preference and that special consideration should be given in a racially neutral manner. (JT)

  8. The Use of Test Results from ASA Workshops to Evaluate Workshop Effectiveness

    ERIC Educational Resources Information Center

    Donegan, Judith H.; And Others

    1976-01-01

    Results of test given to participants in six American Society of Anesthesiologists workshops were analyzed to determine whether attendance increased scores on sequential tests (before, immediately after, and three months later). Both workshop and control groups of anesthesiologists increased their scores with each successive test. (Editor/JT)

  9. A Study of the Geographical Distribution of Undergraduate Students for the Academic Year 1974-1975

    ERIC Educational Resources Information Center

    Schlegel, John F.; And Others

    1975-01-01

    Statistical tables are presented on geographical distribution of undergraduate pharmacy students (U.S., Canadian, and foreign) in U.S. schools. Number of students are listed for each school of pharmacy (resident, non-resident, foreign), for each state of original residence (attending in-state and out-of-state), and for each foreign country. (JT)

  10. National Collegiate Athletic Association's Certification Requirement: A Section 1 Violation of the Sherman Antitrust Act

    ERIC Educational Resources Information Center

    Valparaiso University Law Review, 1974

    1974-01-01

    It is contended that the national Collegiate Athletic Association (NCAA) requirements for certification of amateur athletic events are violative of the Sherman Antitrust Act. Revisions in the certification requirements are suggested which would control the amateur standing and economic exploitation of the athlete but with minimum restriction. (JT)

  11. The Perfect Politician

    ERIC Educational Resources Information Center

    Berry, John N., III

    2010-01-01

    The perfect politician, the ideal political ally to a library, is often but not always an elected official. He or she is always an effective champion of "reasonable financial support," i.e., "the amount...which a thoroughly competent librarian can spend wisely." That is what J.T. Wyer, director of the New York State Library, said in his "What the…

  12. State and Federal Regulation of Collective Negotiations in Higher Education

    ERIC Educational Resources Information Center

    Livingston, Frederick R.; Christensen, Andrea S.

    1971-01-01

    After reviewing the existing legislative and judicial controls that currently provide a legal framework for the exercise of representational interests in the field of higher education, the authors discuss the potential and need for greater government involvement to provide uniform direction and protection of collective bargaining rights. (JT)

  13. 76 FR 72160 - Regulations and Procedures Technical Advisory Committee; Notice of Open Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ..., first serve basis. To join the conference, submit inquiries to Ms. Yvette Springer at Yvette.Springer... the meeting to Ms. Springer via email. For more information, call Yvette Springer at (202) 482-2813. Dated: November 16, 2011 Yvette Springer, Committee Liaison Officer. BILLING CODE 3510-JT-P...

  14. Characteristics of a liquid-helium-free calibration apparatus for cryogenic thermometers

    SciTech Connect

    Shimazaki, T.

    2013-09-11

    Closed-cycle Joule-Thomson (JT) cryocoolers have been developed at National Metrology Institute of Japan (NMIJ)/National Institute of Advanced Industrial Science and Technology (AIST) with the aim of realizing a liquid-helium-free calibration apparatus for cryogenic thermometers between 0.65 K and 25 K. The latest JT cryocooler at NMIJ/AIST consists of a {sup 3}He JT cooling circuit and a pulse tube mechanical refrigerator. The characteristics of the apparatus including a residual gas analysis of the JT cooling circuit are presented in this paper. Currently the initial cool-down is performed using a heat-exchange gas. It normally takes about 30 h to reduce the temperature from room temperature to 5 K at the thermometer comparison block of the apparatus. The correct timing of the removal of the heatexchange gas is important for the efficient operation of the apparatus. Incomplete removal of the heat-exchange gas induces excess heat load on the apparatus and thermal disturbances. Some examples of abrupt temperature bursts are discussed in this paper. Mechanical refrigerators generate cyclic mechanical vibrations, and precision resistance thermometers are usually very sensitive to a mechanical vibration. The measured vibration level of the developed apparatus is reported. The damage to the apparatus due to the magnitude 9.0 earthquake on March 11, 2011, and possible countermeasures in the case of future earthquakes are also discussed.

  15. Bookstore in Trouble: The Proverbial Iceberg

    ERIC Educational Resources Information Center

    Sanderson, Ivan L.

    1975-01-01

    Examines the plight of two troubled bookstores, both state system stores with state charters as nonprofit corporations, probing some of their weaknesses, failures, and resultant difficulties and the positive action, including structural change and new management, involved in recovery and restoration of adequate operating funds. (JT)

  16. Copyright

    ERIC Educational Resources Information Center

    Winkler, Karen J.

    1975-01-01

    Issues involved in the new national copyright bill approved by the Senate and under study in the House of Representatives are examined, particularly the interests of publishers, educators, and librarians with regard to the photocopying of articles in periodicals for classroom use or interlibrary loan. (JT)

  17. The Student-Athlete and the National Collegiate Athletic Association: The Need for a Prima Facie Tort Doctrine

    ERIC Educational Resources Information Center

    Duckworth, Roy D., III

    1975-01-01

    In examining whether courts have jurisdiction to hear student-athlete grievances against the National Collegiate Athletic Association (NCAA) the author rejects the position that the NCAA's activities are under cover of state law, and instead proposes that the student-athlete's remedy lies in an action against the NCAA for a prima facie tort. (JT)

  18. INHIBITION OF AROMATASE CYTOCHROME P-450 (ESTROGEN SYNTHETASE) BY DERIVATIVES OF ALPHA-NAPHTHOFLAVONE

    EPA Science Inventory

    alpha-Naphthoflavone (ANF; 7,8-benzoflavone) is a potent competitive inhibitor of human aromatase cytochrome P-450 (J.T. Kellis, Jr. and L.E. Vickery, Science 225, 1032 (1984)). The authors have further investigated inhibition of aromatase by several derivatives of ANF. Using hum...

  19. English Literature as a Passive Catalyst to Success in English Language at the School Certificate/General Certificate of Education 0-Level Examination

    ERIC Educational Resources Information Center

    Labor, Adonis F.; Sengova, Mathew J.

    1974-01-01

    Reports research in Sierra Leone investigating whether the study of English Literature influences secondary school pupils' competence in English language. Grades of 663 pupils who took both courses were compared with those of 490 who took only language. Results indicate that literature did not aid in language study. (JT)

  20. Cultural conditions on the production of extracellular enzymes by Trichoderma isolates from tobacco rhizosphere

    PubMed Central

    Mallikharjuna Rao, K.L.N.; Siva Raju, K.; Ravisankar, H.

    2016-01-01

    Twelve isolates of Trichoderma spp. isolated from tobacco rhizosphere were evaluated for their ability to produce chitinase and β-1,3-glucanase extracellular hydrolytic enzymes. Isolates ThJt1 and TvHt2, out of 12 isolates, produced maximum activities of chitinase and β-1,3-glucanase, respectively. In vitro production of chitinase and β-1,3-glucanase by isolates ThJt1 and TvHt2 was tested under different cultural conditions. The enzyme activities were significantly influenced by acidic pH and the optimum temperature was 30 °C. The chitin and cell walls of Sclerotium rolfsii, as carbon sources, supported the maximum and significantly higher chitinase activity by both isolates. The chitinase activity of isolate ThJt1 was suppressed significantly by fructose (80.28%), followed by glucose (77.42%), whereas the β-1,3-glucanase activity of ThJt1 and both enzymes of isolate TvHt2 were significantly suppressed by fructose, followed by sucrose. Ammonium nitrate as nitrogen source supported the maximum activity of chitinase in both isolates, whereas urea was a poor nitrogen source. Production of both enzymes by the isolates was significantly influenced by the cultural conditions. Thus, the isolates ThJt1 and TvHt2 showed higher levels of chitinase and β-1,3-glucanase activities and were capable of hydrolyzing the mycelium of S. rolfsii infecting tobacco. These organisms can be used therefore for assessment of their synergism in biomass production and biocontrol efficacy and for their field biocontrol ability against S. rolfsii and Pythium aphanidermatum infecting tobacco. PMID:26887223

  1. Cultural conditions on the production of extracellular enzymes by Trichoderma isolates from tobacco rhizosphere.

    PubMed

    Mallikharjuna Rao, K L N; Siva Raju, K; Ravisankar, H

    2016-01-01

    Twelve isolates of Trichoderma spp. isolated from tobacco rhizosphere were evaluated for their ability to produce chitinase and β-1,3-glucanase extracellular hydrolytic enzymes. Isolates ThJt1 and TvHt2, out of 12 isolates, produced maximum activities of chitinase and β-1,3-glucanase, respectively. In vitro production of chitinase and β-1,3-glucanase by isolates ThJt1 and TvHt2 was tested under different cultural conditions. The enzyme activities were significantly influenced by acidic pH and the optimum temperature was 30°C. The chitin and cell walls of Sclerotium rolfsii, as carbon sources, supported the maximum and significantly higher chitinase activity by both isolates. The chitinase activity of isolate ThJt1 was suppressed significantly by fructose (80.28%), followed by glucose (77.42%), whereas the β-1,3-glucanase activity of ThJt1 and both enzymes of isolate TvHt2 were significantly suppressed by fructose, followed by sucrose. Ammonium nitrate as nitrogen source supported the maximum activity of chitinase in both isolates, whereas urea was a poor nitrogen source. Production of both enzymes by the isolates was significantly influenced by the cultural conditions. Thus, the isolates ThJt1 and TvHt2 showed higher levels of chitinase and β-1,3-glucanase activities and were capable of hydrolyzing the mycelium of S. rolfsii infecting tobacco. These organisms can be used therefore for assessment of their synergism in biomass production and biocontrol efficacy and for their field biocontrol ability against S. rolfsii and Pythium aphanidermatum infecting tobacco. PMID:26887223

  2. Origin of distinct structural symmetry of the neopentane cation in the ground electronic state compared to the methane cation.

    PubMed

    Mondal, T

    2016-04-21

    An ab initio quantum dynamics study has been performed to explore the distinct structural symmetry of C(CH3)4(+) in the ground electronic state compared to CH4(+). Additionally, the underlying details of the highly diffuse and complex vibronic structure of the first photoelectron band of C(CH3)4 have been investigated. Associated potential energy surfaces over the two-dimensional space of nuclear coordinates, subject to the T2⊗ (e + t2) Jahn-Teller effect, are established from extensive electronic structure calculations and (then) the nuclear dynamics calculations are done on them via wave packet propagation including the nonadiabatic coupling of the three electronic sheets. The theoretical results are in good agreement with experimental observations. The JT stabilization energies due to T2⊗e, T2⊗t2 and T2⊗ (e + t2) distortions in the X[combining tilde](2)T2 electronic manifold of C(CH3)4(+) illustrate that the highest stabilization occurs through the T2⊗t2-JT distortion (in the ground state of C(CH3)4(+)). However, CH4(+) gains such maximum stabilization due to T2⊗ (e + t2)-JT distortion. From this novel result and applying the epikernel principle, we propose that the structural evolution of C(CH3)4(+) from Td to C3v minimum energy configuration occurs via JT active vibrations of t2 symmetry, whereas CH4(+) rearranges to the C2v structure through a combination of JT active e and t2 bending vibrations. PMID:27030072

  3. Featured Image: The Q Continuum Simulation

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-10-01

    Each frame in this image (click for the full view!) represents a different stage in the simulated evolution of our universe, ending at present day in the rightmost panel. In a recently-published paper, Katrin Heitmann (Argonne National Laboratory) and collaborators reveal the results from and challenges inherent in the largest cosmological simulation currently available: the Q Continuum simulation. Evolving a volume of (1300 Mpc)3, this massive N-body simulation tracks over half a trillion particles as they clump together as a result of their mutual gravity, imitating the evolution of our universe over the last 13.8 billion years. Cosmological simulations such as this one are important for understanding observations, testing analysis pipelines, investigating the capabilities of future observing missions, and much more. For more information and the original image (as well as several other awesome images!), see the paper below.Citation:Katrin Heitmann et al 2015 ApJS 219 34. doi:10.1088/0067-0049/219/2/34

  4. Decorated Shastry-Sutherland lattice in the spin-(1)/(2) magnet CdCu2(BO3)2

    NASA Astrophysics Data System (ADS)

    Janson, O.; Rousochatzakis, I.; Tsirlin, A. A.; Richter, J.; Skourski, Yu.; Rosner, H.

    2012-02-01

    We report the microscopic magnetic model for the spin-1/2 Heisenberg system CdCu2(BO3)2, one of the few quantum magnets showing the 1/2-magnetization plateau. Recent neutron diffraction experiments on this compound [M. Hase , Phys. Rev. BPLRBAQ0556-280510.1103/PhysRevB.80.104405 80, 104405 (2009)] evidenced long-range magnetic order, inconsistent with the previously suggested phenomenological magnetic model of isolated dimers and spin chains. Based on extensive density functional theory band structure calculations, exact diagonalizations, quantum Monte Carlo simulations, third-order perturbation theory as well as high-field magnetization measurements, we find that the magnetic properties of CdCu2(BO3)2 are accounted for by a frustrated quasi-2D magnetic model featuring four inequivalent exchange couplings: the leading antiferromagnetic coupling Jd within the structural Cu2O6 dimers, two interdimer couplings Jt1 and Jt2, forming magnetic tetramers, and a ferromagnetic coupling Jit between the tetramers. Based on comparison to the experimental data, we evaluate the ratios of the leading couplings Jd : Jt1 : Jt2 : Jit = 1 : 0.20 : 0.45 : -0.30, with Jd of about 178 K. The inequivalence of Jt1 and Jt2 largely lifts the frustration and triggers long-range antiferromagnetic ordering. The proposed model accounts correctly for the different magnetic moments localized on structurally inequivalent Cu atoms in the ground-state magnetic configuration. We extensively analyze the magnetic properties of this model, including a detailed description of the magnetically ordered ground state and its evolution in magnetic field with particular emphasis on the 1/2-magnetization plateau. Our results establish remarkable analogies to the Shastry-Sutherland model of SrCu2(BO3)2, and characterize the closely related CdCu2(BO3)2 as a material realization for the spin-1/2 decorated anisotropic Shastry-Sutherland lattice.

  5. Assessment of physical fitness and exercise tolerance in children with developmental coordination disorder.

    PubMed

    Farhat, Faiçal; Hsairi, Ines; Baiti, Hamza; Cairney, John; Mchirgui, Radhouane; Masmoudi, Kaouthar; Padulo, Johnny; Triki, Chahinez; Moalla, Wassim

    2015-01-01

    Children with developmental coordination disorder (DCD) have been shown to be less physically fit when compared to their typically developing peers. The purpose of the present study was to examine the relationships among body composition, physical fitness and exercise tolerance in children with and without DCD. Thirty-seven children between the ages of 7 and 9 years participated in this study. Participants were classified according to results obtained on the Movement Assessment Battery for Children (MABC) and were divided in 2 groups: 19 children with DCD and 18 children without DCD. All children performed the following physical fitness tests: The five-jump test (5JT), the triple-hop distance (THD) and the modified agility test (MAT). Walking distance was assessed using the 6-min walking test (6MWT). Children with DCD showed higher scores than children without DCD in all MABC subscale scores, as well as in the total score (p<0.001). Participants with DCD were found to perform significantly worse on the MAT (p<0.001), the THD (p<0.001) and 5JT (p<0.05). Moreover, children with DCD had poorer performance on the 6MWT than children without DCD (p<0.01). Our results found significant correlations among body mass index (BMI), THD (r=0.553, p<0.05), 5JT (r=0.480, p<0.05) and 6MWT (r=0.544, p<0.05) only in DCD group. A significant correlation between MAT and 5JT (r=-0.493, p<0.05) was found. Similarly, THD and 5JT (r=0.611, p<0.01) was found to be correlated in children with DCD. We also found relationships among 6MWT and MAT (r=-0.522, p<0.05) and the 6MWT and 5JT (r=0.472, p<0.05) in DCD group. In addition, we found gender specific patterns in the relationship between exercise tolerance, explosive strength, power, DCD, and BMI. In conclusion, the present study revealed that BMI was indicative of poorer explosive strength, power and exercise tolerance in children with DCD compared to children without DCD probably due to a limited coordination on motor control. PMID:26263407

  6. Development of improved-durability plasma sprayed ceramic coatings for gas turbine engines

    NASA Technical Reports Server (NTRS)

    Sumner, I. E.; Ruckle, D. L.

    1980-01-01

    As part of a NASA program to reduce fuel consumption of current commercial aircraft engines, methods were investigated for improving the durability of plasma sprayed ceramic coatings for use on vane platforms in the JT9D turbofan engine. Increased durability concepts under evaluation include use of improved strain tolerant microstructures and control of the substrate temperature during coating application. Initial burner rig tests conducted at temperatures of 1010 C (1850 F) indicate that improvements in cyclic life greater than 20:1 over previous ceramic coating systems were achieved. Three plasma sprayed coating systems applied to first stage vane platforms in the high pressure turbine were subjected to a 100-cycle JT9D engine endurance test with only minor damage occurring to the coatings.

  7. Core noise measurements from a small, general aviation turbofan engine

    NASA Technical Reports Server (NTRS)

    Reshotko, M.; Karchmer, A.

    1980-01-01

    As part of a program to investigate combustor and other core noises, simultaneous measurements of internal fluctuating pressure and far field noise were made with a JT15D turbofan engine. Acoustic waveguide probes, located in the engine at the combustor, at the turbine exit and in the core nozzle wall, were used to measure internal fluctuating pressures. Low frequency acoustic power determined at the core nozzle exit corresponds in level to the far-field acoustic power at engine speeds below 65% of maximum, the approach condition. At engine speeds above 65% of maximum, the jet noise dominates in the far-field, greatly exceeding that of the core. From coherence measurements, it is shown that the combustor is the dominant source of the low frequency core noise. The results obtained from the JT15D engine were compared with those obtained previously from a YF102 engine, both engines having reverse flow annular combustors and being in the same size class.

  8. Core noise measurements from a small, general aviation turbofan engine

    NASA Technical Reports Server (NTRS)

    Reshotko, M.; Karchmer, A.

    1980-01-01

    As part of a program to investigate combustor and other core noises, simultaneous measurements of internal fluctuating pressure and far field noise were made with a JT15D turbofan engine. Acoustic waveguide probes, located in the engine at the combustor, at the turbine exit and in the core nozzle wall, were used to measure internal fluctuating pressures. Low frequency acoustic power determined at the core nozzle exit corresponds in level to the far field acoustic power at engine speeds below 65% of maximum, the approach condition. At engine speeds above 65% of maximum, the jet noise dominates in the far field, greatly exceeding that of the core. From coherence measurements, it is shown that the combustor is the dominant source of the low frequency core noise. The results obtained from the JT15D engine were compared with those obtained previously from a YF102 engine, both engines having reverse flow annular combustors and being in the same size class.

  9. Improved stop cylinder loading scheme for a centrifuge pellet accelerator

    NASA Astrophysics Data System (ADS)

    Lang, P. T.; Cierpka, P.; Horton, L.; Lorenz, A.; Watson, M. J.; Twynam, P.; Walden, A.; Wijetunge, S.; Willis, B.; Hosogane, N.; Hiratsuka, H.; Kizu, K.

    2000-10-01

    In order to perform plasma refueling experiments with cryogenic hydrogen pellets at the midsize tokamak ASDEX Upgrade, a centrifuge injector was developed based on the novel stop cylinder principle. Following the demonstration of excellent performance with this instrument, similar injectors were constructed for two of the world's largest tokamaks, JET and JT-60U. The extended fuel consumption in these tokamaks enforced the employment of continuous extruders instead of a storage cryostat, requiring an increase in pellet temperature from 8 to 14 K. Degradation of the injector performance was found at these higher pellet temperatures due to increased gas evaporation rates but could be eliminated by a revised acceleration scheme. Applying the adapted setup, reliable and stable operation has been realized with JET and JT-60U injectors.

  10. High-power test of lower hybrid vacuum window

    NASA Astrophysics Data System (ADS)

    Maebara, S.; Ikeda, Y.; Sakamoto, K.; Nagashima, T.; Arai, H.; Goto, N.

    1989-07-01

    1 MW class of RF vacuum window at a frequency of 2 GHz is under development for a new LHRF heating system in JT-60 upgrade program. The power capability of a conventional pillbox window, which is used in the JT-60 LHRF heating system, is restricted by the multipactoring discharge at the power level of more than 500 kW. In the high power experiment on test stand, it was found that the multipactoring discharge is caused by the perpendicular electric field Ez to the ceramic. To suppress the multipactoring discharge at higher power level, a new pillbox window for reducting the perpendicular electric field Ez was designed from a numerical analysis.

  11. Spectroscopic determination of kinetic parameters for frequency sweeping Alfven eigenmodes

    SciTech Connect

    Lesur, M.; Idomura, Y.; Shinohara, K.; Garbet, X.

    2010-12-15

    A method for analyzing fundamental kinetic plasma parameters, such as linear drive and external damping rate, based on experimental observations of chirping Alfven eigenmodes, is presented. The method, which relies on new semiempirical laws for nonlinear chirping characteristics, consists of fitting procedures between the so-called Berk-Breizman model and the experiment in a quasiperiodic chirping regime. This approach is applied to the toroidicity induced Alfven eigenmode (TAE) on JT-60 Upgrade (JT-60U) [N. Oyama et al., Nucl. Fusion 49, 104007 (2009)], which yields an estimation of the kinetic parameters and suggests the existence of TAEs far from marginal stability. Two collision models are considered, and it is shown that dynamical friction and velocity-space diffusion are essential to reproduce nonlinear features observed in experiments. The results are validated by recovering measured growth and decay of perturbation amplitude and by estimating collision frequencies from experimental equilibrium data.

  12. Design of a valved moving magnet type linear compressor for a Joule-Thomson cryocooler

    NASA Astrophysics Data System (ADS)

    Wang, W. W.; Wang, L. Y.; Gan, Z. H.

    2014-01-01

    For temperatures around 4-6 K, Joule-Thomson (J-T) cryocoolers can achieve a higher efficiency than Stirling or pulse tube cryocoolers thus have been widely used in space. It is crucial for a J-T compressor to obtain a relatively high pressure ratio. With this concept, a valved moving magnet type linear compressor has been designed. This paper describes the design method and component structure of the linear compressor in detail. The electromagnetic force of linear motor, stiffness and stress distribution of flexure springs were calculated based on finite element method (FEM). System resonance was specially considered to achieve a high efficiency, and system vibration and heat dissipation problems were discussed. The design goal of the linear compressor is to achieve an efficiency of 80% and a lifetime longer than 5 years.

  13. Low pollution combustor designs for CTOL engines - Results of the Experimental Clean Combustor Program

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Peduzzi, A.; Niedzwiecki, R. W.

    1976-01-01

    The NASA/Pratt & Whitney Aircraft Experimental Clean Combustor Program is a multi-year, major contract effort. Primary program objectives are the generation of combustor technology for development of advanced commercial CTOL engines with lower exhaust emissions than current aircraft and demonstration of this technology in a full-scale JT9D engine in 1976. This paper describes the pollution and performance goals, Phase I and II test results, and the Phase III combustor hardware, pollution sampling techniques, and test plans. Best results were obtained with the Vorbix concept which employs multiple burning zones and improved fuel preparation and distribution. Substantial reductions were achieved in all pollutant categories, meeting the 1979 EPA standards for NOx, THC, and smoke when extrapolated to JT9D cycle conditions. The Vorbix concept additionally demonstrated the capability for acceptable altitude relight and did not appear to have unsolvable durability or exit temperature distribution problems.

  14. The pollution reduction technology program for can-annular combustor engines - Description and results

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Fiorentino, A. J.; Diehl, L.

    1976-01-01

    Pollutant reduction and performance characteristics were determined for three successively more advanced combustor concepts. Program Element I consisted of minor modifications to the current production JT8D combustor and fuel system to evaluate means of improved fuel preparation and changes to the basic airflow distribution. Element II addressed versions of the two-staged Vorbix (vortex burning and mixing) combustor and represented a moderate increase in hardware complexity and difficulty of development. The concept selected for Element III employed vaporized fuel as a means of achieving minimum emission levels and represented the greatest difficulty of development and adaptation to the JT8D engine. Test results indicate that the Element I single-stage combustors were capable of dramatic improvement in idle pollutants. The multistage combustors evaluated in Program Elements II and III simultaneously reduced CO, THC and NOx emissions, but were unable to satisfy the current 1979 EPA standards.

  15. QUANTITATIVE TESTS OF ELMS AS INTERMEDIATE N PEELING-BALOONING MODES

    SciTech Connect

    LAO,LL; SNYDER,PB; LEONARD,AW; OIKAWA,T; OSBORNE,TH; PETRIE,TW; FERRON,JR; GROEBNER,RJ; HORTON,LD; KAMADA,Y; MURAKAMI,M; SAARELMA,S; STJOHN,HE; TURNBULL,AD; WILSON,HR

    2003-03-01

    A271 QUANTITATIVE TESTS OF ELMS AS INTERMEDIATE N PEELING-BALOONING MODES. Several testable features of the working model of edge localized modes (ELMs) as intermediate toroidal mode number peeling-ballooning modes are evaluated quantitatively using DIII-D and JT-60U experimental data and the ELITE MHD stability code. These include the hypothesis that ELM sizes are related to the radial widths of the unstable MHD modes, the unstable modes have a strong ballooning character localized in the outboard bad curvature region, and ELM size generally becomes smaller at high edge collisionality. ELMs are triggered when the growth rates of the unstable MHD modes become significantly large. These testable features are consistent with many ELM observations in DIII-D and JT-60U discharges.

  16. Plate fin heat exchanger model with axial conduction and variable properites

    NASA Astrophysics Data System (ADS)

    Hansen, Benjamin Jacob; White, Michael Joseph; Klebaner, Arkadiy

    2012-06-01

    Future superconduction radio frequency (SRF) cavities, as part of Project X at Fermilab,will be cooled to superfluid helium temperatures by a cryogenic distribution system supplying cold supercritical helium. To reduce vapor fraction during the final Joule Thomson (J-T) expansion into the superfluid helium cooling bath, counter-flow, plate-fin heat exchanger are an effective option. However, at liquid helium temperatures requires consideration of axial heat conduction along the direction of flow, in addition to variable fluid properties. Here we present a numberical model that includes the effects of axial guide design decisions on heat exhanger material choice and geometry. In addition, the J-T expansion process is modeled with the heat exchanger to analyze the effect of heat load and cryogenic supply parameters.

  17. Effect of forward motion on engine noise

    NASA Technical Reports Server (NTRS)

    Blankenship, G. L.; Low, J. K. C.; Watkins, J. A.; Merriman, J. E.

    1977-01-01

    Methods used to determine a procedure for correcting static engine data for the effects of forward motion are described. Data were analyzed from airplane flyover and static-engine tests with a JT8D-109 low-bypass-ratio turbofan engine installed on a DC-9-30, with a CF6-6D high-bypass-ratio turbofan engine installed on a DC-10-10, and with a JT9D-59A high-bypass-ratio turbofan engine installed on a DC-10-40. The observed differences between the static and the flyover data bases are discussed in terms of noise generation, convective amplification, atmospheric propagation, and engine installation. The results indicate that each noise source must be adjusted separately for forward-motion and installation effects and then projected to flight conditions as a function of source-path angle, directivity angle, and acoustic range relative to the microphones on the ground.

  18. The effect of external magnetic field on the Raman peaks in manganites

    SciTech Connect

    Sahu, A. K.; Rout, G. C.

    2014-04-24

    We report here a microscopic theoretical model study exhibiting the effect of external magnetic field on the Raman excitation peaks in the CMR manganite system. The Hamiltonian consists of Jahn-Teller (J-T) distortion in e{sub g} band, the double exchange interaction and the Heisenberg spin-spin interaction. Further the phonons are coupled to e{sub g} band electrons, J-T distorted e{sub g} band and the double exchange interaction. The Raman spectral intensity is calculated from the imaginary part of the phonon Green function. The spectra exhibits three peaks besides a very weak high energy peak. The magnetic field effect on these peaks are reported.

  19. Experimental clean combustor program: Noise study

    NASA Technical Reports Server (NTRS)

    Sofrin, T. G.; Riloff, N., Jr.

    1976-01-01

    Under a Noise Addendum to the NASA Experimental Clean Combustor Program (ECCP) internal pressure fluctuations were measured during tests of JT9D combustor designs conducted in a burner test rig. Measurements were correlated with burner operating parameters using an expression relating farfield noise to these parameters. For a given combustor, variation of internal noise with operating parameters was reasonably well predicted by this expression but the levels were higher than farfield predictions and differed significantly among several combustors. For two burners, discharge stream temperature fluctuations were obtained with fast-response thermocouples to allow calculation of indirect combustion noise which would be generated by passage of the temperature inhomogeneities through the high pressure turbine stages of a JT9D turbofan engine. Using a previously developed analysis, the computed indirect combustion noise was significantly lower than total low frequency core noise observed on this and several other engines.

  20. Effect of forward velocity on the noise characteristics of dual-flow jet nozzles

    NASA Technical Reports Server (NTRS)

    Reed, D. H.

    1974-01-01

    Acoustic results of jet noise tests conducted on scale-model nozzles at a wall isolation facility are presented and analyzed. The test fixture featured a triple-flow system for the purpose of simulating freestream flow around hot dual-flow jet nozzles. Test nozzles included 1/20th scale models of the exhaust system for the JT8D-9 engine, power plant for the Boeing 727 airplane (bypass ratio 1) and of the JT8D-109 refan engine (bypass ratio 2). It was found that overall jet noise is reduced by the forward velocity in proportion to the fifth and sixth power of the relative primary jet velocity. Spectral and directivity characteristics are presented.

  1. The design and flight test of an engine inlet bulk acoustic liner

    NASA Technical Reports Server (NTRS)

    Lester, H. C.; Preisser, J. S.; Parrott, T. L.

    1983-01-01

    This paper summarizes the design, fabrication and flight evaluation of a Kevlar acoustic liner configuration for a JT15D turbofan engine. The liner was designed to suppress, by a measurable amount, a dominant (13,0) BPF tone. This tone or spinning mode was produced for research purposes by installing 41 circumferentially distributed small diameter rods upstream of the 28 fan blades. Duct liner attenuations calculated by a finite element procedure were compared to far field power (insertion) losses deduced from flight data. The finite element program modeled the variable geometry of the JT15D inlet and used a uniform flow with a boundary layer roll-off to model the inlet flow field. Calculated liner losses were generally conservative. That is, measured far field power losses were generally greater than attenuations calculated by the finite element computer program.

  2. Dynamic PID loop control

    SciTech Connect

    Pei, L.; Klebaner, A.; Theilacker, J.; Soyars, W.; Martinez, A.; Bossert, R.; DeGraff, B.; Darve, C.; /Fermilab

    2011-06-01

    The Horizontal Test Stand (HTS) SRF Cavity and Cryomodule 1 (CM1) of eight 9-cell, 1.3GHz SRF cavities are operating at Fermilab. For the cryogenic control system, how to hold liquid level constant in the cryostat by regulation of its Joule-Thompson JT-valve is very important after cryostat cool down to 2.0 K. The 72-cell cryostat liquid level response generally takes a long time delay after regulating its JT-valve; therefore, typical PID control loop should result in some cryostat parameter oscillations. This paper presents a type of PID parameter self-optimal and Time-Delay control method used to reduce cryogenic system parameters oscillation.

  3. Localized electron heating by strong guide-field magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Guo, Xuehan; Inomoto, Michiaki; Sugawara, Takumichi; Yamasaki, Kotaro; Ushiki, Tomohiko; Ono, Yasushi

    2015-10-01

    Localized electron heating of magnetic reconnection was studied under strong guide-field using two merging spherical tokamak plasmas in the University of Tokyo Spherical Tokamak experiment. Our new slide-type two-dimensional Thomson scattering system is documented for the first time the electron heating localized around the X-point. Shape of the high electron temperature area does not agree with that of energy dissipation term Et.jt . If we include a guide-field effect term Bt/(Bp+αBt) for Et.jt , the energy dissipation area becomes localized around the X-point, suggesting that the electrons are accelerated by the reconnection electric field parallel to the magnetic field and thermalized around the X-point.

  4. Low activation austenitic Mn-steel for in-vessel fusion materials

    NASA Astrophysics Data System (ADS)

    Suzuki, Y.; Saida, T.; Kudough, F.

    1998-10-01

    Several compositions of austenitic manganese steels (Mn-steels) were investigated for in-vessel component materials in D-T fueled fusion reactor with respect to radiation exposure and waste disposal management. The 24.5Mn-13.5Cr steel was developed in which undesired impurities, such as Ni, Mo, Nb and Co, were controlled and C (˜0.025wt%) and N (˜0.22wt%) contents were well adjusted for corrosion resistance and weldability. Experimental observation has shown that this steel has a single γ-phase structure and good properties for vacuum vessel almost the same grade as Type 316 stainless steel (316SS), such as low permeability, good weldability, good mechanical properties of strength and toughness and good corrosion resistance. Activation calculations were performed adopting this material for the JT-60 Super Upgrade (JT-60SU) vacuum vessel and the effectiveness of low activation was confirmed.

  5. Dynamic Jahn-Teller Effect in Negatively Charged Nitrogen-Vacancy Center in Diamond

    NASA Astrophysics Data System (ADS)

    Abtew, Tesfaye; Zhang, Peihong

    2011-03-01

    The negatively charged nitrogen-vacancy (NV) center in diamond has attracted much research interest recently owing to its desirable optical properties and long spin coherent lifetime. The ground state of NV- center has a 3 A2 symmetry, which can be optically excited, to a 3 E state. The excited state is orbitally degenerate therefore should experience either static or dynamic Jahn-Teller (JT) effects. We use accurate first-principles methods to study structural and electronic properties of the NV- center in diamond both in the ground and excited states. Our results indicate that the excited state of the NV- center is indeed a dynamic JT system. We acknowledge the Center for Computational Research at the University at Buffalo, SUNY. This work is supported by the National Science Foundation under Grant No. DMR-0946404 and by the Department of Energy under GrantNo. DE-SC0002623.

  6. Gifford-McMahon/Joule-Thomson Refrigerator Cools to 2.5 K

    NASA Technical Reports Server (NTRS)

    Britcliffe, Michael; Fernandez, Jose; Hanson, Theodore

    2005-01-01

    A compact refrigerator designed specifically for cooling a microwave maser low-noise amplifier is capable of removing heat at a continuous rate of 180 mW at a temperature of 2.5 K. This refrigerator is a combination of (1) a commercial Gifford-McMahon (GM) refrigerator nominally rated for cooling to 4 K and (2) a Joule-Thomson (J-T) circuit. The GM refrigerator pre-cools the J-T circuit, which provides the final stage of cooling. The refrigerator is compact and capable of operating in any orientation. Moreover, in comparison with a typical refrigerator heretofore used to cool a maser to 4.5 K, this refrigerator is simpler and can be built at less than half the cost.

  7. TiO2 nanotube (T_NT) surface treatment revisited: Implications of ZnO, TiCl4, and H2O2 treatment on the photoelectrochemical properties of T_NT and T_NT-CdSe

    NASA Astrophysics Data System (ADS)

    Mukherjee, Bratindranath; Wilson, Winn; Subramanian, Vaidyanathan (Ravi)

    2012-12-01

    The surface treatment of an anodized TiO2 nanotube (T_NT) is very desirable for enhancing its photoelectrochemical properties and often is a prerequisite to deposition of any overlying layer for photoactivity efficiency improvement. This study provides a comparative analysis of the effects of such surface treatments and the mechanistic insights behind the observed improvements in the performance of the treated T_NTs. T_NT surface treatment using three approaches, viz., TiCl4, Zn(NH3)42+, and H2O2 is examined. TiCl4 and Zn(NH3)42+ treatment results in the formation of discontinuous islands of the respective oxides with 5-10 nm and 15-20 nm diameter particles. TiCl4 treatment demonstrates an increase of 7.4% in photovoltage and is the most effective of the three approaches. Zn(NH3)42+ treatment also results in an ~2% increase in photovoltage. However, a surface treatment of T_NT using H2O2 results only in a favourable shift in flatband potential (80 mV). The T_NTs are rendered ineffective as H2O2 treatment causes the destabilization of the T_NT at the base. Finally, the activity of an overlying chalcogenide layer is improved with the TiCl4 and Zn(NH3)42+ treatment (and not with H2O2) as evident from the photoelectrochemical responses: (JT_NT-TiO2-CdSe > JT_NT-ZnO-CdSe > JT_NT-CdSe > JT_NT-H2O2-CdSe).The surface treatment of an anodized TiO2 nanotube (T_NT) is very desirable for enhancing its photoelectrochemical properties and often is a prerequisite to deposition of any overlying layer for photoactivity efficiency improvement. This study provides a comparative analysis of the effects of such surface treatments and the mechanistic insights behind the observed improvements in the performance of the treated T_NTs. T_NT surface treatment using three approaches, viz., TiCl4, Zn(NH3)42+, and H2O2 is examined. TiCl4 and Zn(NH3)42+ treatment results in the formation of discontinuous islands of the respective oxides with 5-10 nm and 15-20 nm diameter particles. TiCl4 treatment demonstrates an increase of 7.4% in photovoltage and is the most effective of the three approaches. Zn(NH3)42+ treatment also results in an ~2% increase in photovoltage. However, a surface treatment of T_NT using H2O2 results only in a favourable shift in flatband potential (80 mV). The T_NTs are rendered ineffective as H2O2 treatment causes the destabilization of the T_NT at the base. Finally, the activity of an overlying chalcogenide layer is improved with the TiCl4 and Zn(NH3)42+ treatment (and not with H2O2) as evident from the photoelectrochemical responses: (JT_NT-TiO2-CdSe > JT_NT-ZnO-CdSe > JT_NT-CdSe > JT_NT-H2O2-CdSe). Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr31660a

  8. Development of a microminiature sorption cooler

    NASA Technical Reports Server (NTRS)

    Burger, Johannes; Holland, Harry; terBrake, Marcel; Rogalla, Horst; Wade, Larry

    1997-01-01

    The development of a microcooler for operations below 80 K, for low temperature electronic devices requiring small cooling powers of the order of 10 mW is described. A sorption compressor combined with Joule-Thomson (JT) expansion was selected for miniaturization. The advantage of the system is considered to be its absence of moving parts, with the exception of the check valves. This facilitates the scaling down of the system, minimizes interferences and contributes to a long lifetime. The requirements for small scale cooling of low temperature electronics are listed. The sorption compressor and the JT expansion are described. A parameter study is reviewed together with the scaling of the sorption compressor.

  9. Tunneling in Jahn-Teller Systems and Multidimensional WKB Approximation

    NASA Astrophysics Data System (ADS)

    Polinger, Victor

    We develop a general WKB approach to multidimensional tunneling in Jahn-Teller (JT) systems. To solve the path branching problem, we introduce the so-called junction rule for nodes in a multidimensional web of tunneling paths connecting equivalent wells. For any complex JT system, it provides enough equations to reduce the multidimensional tunneling to one-dimensional penetration through just one potential barrier. The junction rule is shown to include the symmetry properties of the ground-state wave function, same as the operator of symmetry projection. The tunneling splitting energy gap is shown to be proportional to probability flux through the bottle-neck point of the potential barrier, where it is highest. The order of energy levels in the ground-state tunneling multiplet is determined by the factor cos [phi]B, where [phi]B is the corresponding Berry phase. Several examples of practical interest are considered in detail.

  10. Development of a rotor wake/vortex model. Volume 2: User's manual for computer program

    NASA Technical Reports Server (NTRS)

    Majjigi, R. K.; Gliebe, P. R.

    1984-01-01

    The principal objective was to establish a verified rotor wake/vortex model for specific application to fan and compressor rotor-stator interaction and resulting noise generation. A description and flow chart of the Rotor Wake/Vortex Model computer program, a listing of the program, definitions of the input/output parameters, a sample input/output case, and input files for Rotor 55, the JT15D rotor, and Rotor 67, Stage 1 are provided.

  11. Utilizing numerical techniques in turbofan inlet acoustic suppressor design

    NASA Technical Reports Server (NTRS)

    Baumeister, K. J.

    1982-01-01

    Numerical theories in conjunction with previously published analytical results are used to augment current analytical theories in the acoustic design of a turbofan inlet nacelle. In particular, a finite element-integral theory is used to study the effect of the inlet lip radius on the far field radiation pattern and to determine the optimum impedance in an actual engine environment. For some single mode JT15D data, the numerical theory and experiment are found to be in a good agreement.

  12. 40 CFR 180.564 - Indoxacarb; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)-methyl 7-chloro-2,5-dihydro-2- amino]carbonyl]indeno amino]carbonyl]indeno [oxadiazine-4a(3H)-carboxylate...]carbonyl]indeno oxadiazine-4a(3H)-carboxylate, its R-enantiomer, (R)-methyl 7-chloro-2,5-dihydro-2- amino]carbonyl]indeno oxadiazine-4a(3H)-carboxylate, and the metabolites: IN-JT333, methyl...

  13. A Layman's Guide to Thrust Engine Development for Super/Hyper Sonic Flight.

    ERIC Educational Resources Information Center

    Thiesse, James L.

    The intention of this paper is to discuss the advances in thrust engines from the initial development of the J58/SR-71 (JT11D-20) of the U.S. Air Force's SR-71 Blackbird to the development of the RAM and SCRAM engines necessary to propel the new generations of high-flying super-speed aircraft. Engineering complexities suggest that the engines and…

  14. Corrigendum Corrigendum: Association between TAP1 gene polymorphisms and alopecia areata in a Korean population - Genet. Mol. Res. 14 (4): 18820-18827.

    PubMed

    Kim, H K; Lee, H; Lew, B L; Sim, W Y; Kim, Y O; Lee, S W; Lee, S; Cho, I H; Kwon, J T; Kim, H J

    2016-01-01

    H.K. Kim(1)*, H. Lee(1)*, B.L. Lew(2), W.Y. Sim(2), Y.O. Kim(3), S.W. Lee(3), S. Lee(4), I.H. Cho(5), J.T. Kwon(1) and H.J. Kim(1,6) (5)Department of Convergence Medical Science, Brain Korea 21 Plus Program, and Institute of Korean Medicine, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea. PMID:26985926

  15. Survival and mitochondrial function in septic patients according to mitochondrial DNA haplogroup

    PubMed Central

    2012-01-01

    Introduction We recently found that platelet cytochrome c oxidase (COX) activities and quantities in 6-month-survival septic patients are significantly higher than those of patients who died before 6 months. Other studies suggested that the mitochondrial DNA (mtDNA) genotype could play a major role in sepsis survival. Given that COX catalytic subunits are encoded by mtDNA, the objective of the present study was to explore whether mtDNA population genetic variation could affect COX activity and quantity and favors sepsis survival. Methods A prospective, multicenter, observational study was carried out in six Spanish ICUs. We included 96 patients with severe sepsis. We determined the mtDNA haplogroup, the COX specific activity/citrate synthase specific activity (COXa/CSa) ratio and the COX quantity/citrate synthase specific activity (COXq/CSa) ratio in circulating platelets at the time of diagnosis, day 4 and day 8. We used survival at 1 and 6 months as endpoints. Results Patients with the JT mtDNA haplogroup (n = 15) showed higher COXq/CSa ratio at day 4 (P = 0.04) and day 8 (P = 0.02) than those with other haplogroups (n = 81). Logistic regression analysis showed that the JT mtDNA haplogroup (odds ratio = 0.18; 95% confidence interval = 0.04 to 0.94; P = 0.04) and COXq/CSa ratio (odds ratio = 0.53; 95% confidence interval = 0.30 to 0.93; P = 0.03) were associated with 1-month survival after controlling for age and lactic acid levels. Conclusions The novel findings of our study are that 1-month surviving septic patients showed higher COXq/CSa ratio than nonsurviving individuals, that patients from the JT mtDNA haplogroup showed a higher COXq/CSa ratio and that JT patients had a higher 1-month survival than patients from other mtDNA haplogroups. PMID:22251664

  16. Summary of emissions reduction technology programs

    NASA Technical Reports Server (NTRS)

    Niedzwiecki, R. W.

    1977-01-01

    The NASA emissions reduction contract programs for EPA aircraft engine classes P2 (turboshaft engines), T1 (jet engines with thrust under 8000 lb), T4 (JT8D) engines), and T2 (jet engines with thrust over 8000 lb) are discussed. The most important aspects of these programs, the commonality of approaches used, the test results, and assessments regarding applications of the derived technology are summarized.

  17. Hereditary Hyperparathyroidism–Jaw Tumor Syndrome: The Endocrine Tumor Gene HRPT2 Maps to Chromosome 1q21-q31

    PubMed Central

    Szabó, József; Heath, Brett; Hill, Virginia M.; Jackson, Charles E.; Zarbo, Richard J.; Mallette, Lawrence E.; Chew, Shern L.; Besser, Gordon M.; Thakker, Rajesh V.; Huff, Vicki; Leppert, Mark F.; Heath, Hunter

    1995-01-01

    The syndrome of hereditary hyperparathyroidism and jaw tumors (HPT-JT) is characterized by inheritance, in an autosomal dominant pattern, of recurrent parathyroid adenomas, fibro-osseous tumors of the mandible and/or maxilla, Wilms tumor, and parathyroid carcinoma. This syndrome is clinically and genetically distinct from other endocrine neoplasia syndromes and appears to result from mutation of an endocrine tumor gene designated “HRPT2.” We studied five HPT-JT families (59 persons, 20 affected); using PCR-based markers, we instituted a genomewide linkage search after excluding several candidate genes. Lod scores were calculated at various recombination fractions (θ), penetrance 90%. We mapped HRPT2 to the long arm of chromosome 1 (1q21-q31). The maximal lod score was 6.10 at θ = .0 with marker D1S212, or >106 odds in favor of linkage. In six hereditary Wilms tumor families (96 persons, 29 affected), we found no linkage to 1q markers closely linked with HRPT2 (lod scores −15.6 [D1S191] and −17.8 [D1S196], θ = .001). Nine parathyroid adenomas and one Wilms tumor from nine members of three HPT-JT families were examined for loss of heterozygosity at linked loci. The parathyroid adenomas and Wilms tumor showed no loss of heterozygosity for these DNA markers. Our data establish that HRPT2, an endocrine tumor gene on the long arm of chromosome 1, is responsible for the HPT-JT syndrome but not for the classical hereditary Wilms tumor syndrome. ImagesFigure 1 PMID:7717405

  18. Search for short lived neutral particle in the 15.1 MeV isovector transition of 12C

    NASA Astrophysics Data System (ADS)

    Datar, V. M.; Fortier, S.; Gales, S.; Hourani, E.; Langevin, H.; Maison, J. M.; Massolo, C. P.

    1988-01-01

    We report a search for a short lived neutral particle ? emitted in the decay of the 15.1 MeV J?(T)=1+(1) state in 12C. The experiment is sensitive to ?-->e+e- decays and finds no evidence for such a particle. We set upper limits on ??/?? for mean lifetimes between ~10-13 and ~10-8 sec and in the mass range 1.02-2.5 MeV.

  19. Review of Japanese results on heating and current drive

    NASA Astrophysics Data System (ADS)

    Watari, T.

    1992-10-01

    This article discusses Japanese contributions in the fields of plasma heating and current drive and, together with other reviews presented at this conference, will serve as a reference for future investigations. The Japanese fusion community has several tokamaks: JAERI (STA) has JT-60 and JFT-2M. TRIAM-1M (Kyushu University), WT-3 (Kyoto University), and JIPP T-2 U (National Institute for Fusion Science (NIFS)) belong to the Ministry of Education (MOE). A lot of contributions were made by these devices in heating and current drive in the various frequency ranges: electron cyclotron (EC) frequency range, lower hybrid (LH) frequency range, and ion cyclotron (IC) frequency range. This paper only deals with tokamak results: results on LHCD are described in section 1; ECH is described in section 2; results of high power ICRF heating are given in section 3; IBWH is described in section 4; and finally, FWCD is covered in section 5. Because the Matrix of different machine and different frequency range gives an intractable list of results, sampling will be made in describing the progress, i.e., JT-60 for LHCD, WT-3 for ECH/CD, JIPP T-2 U for IBWH, and JT-60 for higher harmonic ICRF heating. Special attention is given to the investigation of fast wave current drive which has some history in Japan. Results from JIPP T-2 U, JFT-2M, HT-2, and JT-60 are summarized. Aside from the tokamak, MOE has an alternative magnetic fusion program centered around CHS and HELIOTORON-E (Kyoto University). The LHD (Large Helical Device) is a machine under construction in the new site of NIFS. Gamma-10 (Tsukuba University) and HIEI (Kyoto University) are tandem mirror type open end systems. Due to the allotted space, works in this field will not be covered in this review. It should also be noted that there are a lot of contributions in theory which continued to support experiments very strongly through this decade.

  20. Spectral flame radiance from a tubular-can combustor

    NASA Technical Reports Server (NTRS)

    Claus, R. W.

    1981-01-01

    An experimental investigation was conducted to determine the effects of fuel type, fuel-air ratio, and inlet-air pressure on the spectral flame radiance emanating from a JT8D can combustor. Spectral radiance measurements from 1.55 to 5.5 micrometers of wavelength were recorded and analyzed to determine soot concentration and flame temperature at various axial locations in the combustor. Two fuels differing in volatility, viscosity, and chemical composition were used in this investigation.

  1. Status of Fusion Experimental Reactor (FER) design

    SciTech Connect

    Tone, T.; Fujisawa, N.; Sugihara, M.

    1985-07-01

    Conceptual design studies of the Fusion Experimental Reactor (FER) have been conducted at JAERI in line with a long-range plan for fusion reactor development laid out in the long-term program of the Atomic Energy Commission issued in 1982. The FER succeeding the tokamak device JT-60 is a tokamak reactor with a major mission of realizing a self-ignited long-burning DT plasma and demonstrating engineering feasibility. The paper describes recent developments of the FER design concept.

  2. Two cases of multiple ossifying fibromas in the jaws

    PubMed Central

    2014-01-01

    Background The clinicopathologic characteristics of multiple ossifying fibroma (OF) are unclear due to the condition’s rarity, making diagnosis challenging. Sporadic multiple OFs must be distinguished from hyperparathyroidism-jaw tumour syndrome (HPT-JT) related OF and other fibro-osseous lesions. Methods Multiple OF cases were identified from ossifying fibroma cases. Clinical data including age, sex, anatomic site, radiographic features, clinical impression, treatment and available follow-up data as well as serum calcium, phosphorus, and parathyroid hormone (PTH) were recorded. GNAS and HRPT2 genetic mutations were examined in the two present cases. Case reports of sporadic multiple ossifying fibroma and HPT-JT-related OF were also reviewed. Results The two present cases were confirmed as sporadic multiple OF, with no genetic GNAS and HRPT2 mutations found. The incidence of sporadic multiple ossifying fibroma was 2.0% (2/102). The total 18 sporadic multiform OF cases were characterized as followed: 13 (72.2%) female; 5 (27.8%) male; mean age 28.6 years; 2/16 (11.1%) cases only in the mandible; 4/18 (22.2%) cases only in the maxilla; and 12/18 (66.7%) cases in both the maxilla and mandible. Radiographically, the lesions were radiolucent in 5/18 (27.8%) cases and mixed density in 13/18 (72.2%) cases. Along with 24 cases of HPT-JT related OF were reviewed, sixteen (66.7%) patients were diagnosed with a single lesion, and 8 patients (33.3%) were diagnosed with multiple jaw lesions. Conclusions Sporadic multiple OFs are very rare, but must be distinguished from HPT-JT related OF. We strongly recommend that patients diagnosed with multiple ossifying fibromas receive serum PTH testing and mutation screening of HRPT2. Virtual slides http://www.diagnosticpathology.diagnomx.eu/vs/1194507146115753 PMID:24678936

  3. Hereditary hyperparathyroidism-jaw tumor syndrome: the endocrine tumor gene HRPT2 maps to chromosome 1q21-q31

    SciTech Connect

    Szabo, J.; Heath, B.; Hill, V.M.; Heath, H. III; Leppert, M.F.; Jackson, C.E.; Zarbo, R.J.; Mallette, L.E.; Huff, V.; Chew, S.L.

    1995-04-01

    The syndrome of hereditary hyperparathyroidism and jaw tumors (HPT-JT) is characterized by inheritance, in an autosomal dominant pattern, of recurrent parathyroid adenomas, fibro-osseous tumors of the mandible and/or maxilla, Wilms tumor, and parathyroid carcinoma. This syndrome is clinically and genetically distinct from other endocrine neoplasia syndromes and appears to result from mutation of an endocrine tumor gene designated {open_quotes}HRPT2{close_quotes}. We studied five HPT-JT families (59 persons, 20 affected); using PCR-based markers, we instituted a genome-wide linkage search after excluding several candidate genes. Lod scores were calculated at various recombination fractions ({theta}), penetrance 90%. We mapped HRPT2 to the long arm of chromosome 1 (1q21-q31). The maximal lod score was 6.10 at {theta} = .0 with marker D1S212, or >10{sup 6} odds in favor of linkage. In six hereditary Wilms tumor families (96 persons, 29 affected), we found no linkage to 1q markers closely linked with HRPT2 (lod scores -15.6 [D1S191] and -17.8 [D1S196], {theta} = .001). Nine parathyroid adenomas and one Wilms tumor from nine members of three HPT-JT families were examined for loss of heterozygosity at linked loci. The parathyroid adenomas and Wilms tumor showed no loss of heterozygosity for these DNA markers. Our data establish that HRPT2, an endocrine tumor gene on the long arm of chromosome 1, is responsible for the HPT-JT syndrome but not for the classical hereditary Wilms tumor syndrome. 32 refs., 2 figs., 2 tabs.

  4. Papers from the Fifth Regional Meeting of the Chicago Linguistic Society, April 18-19, 1969.

    ERIC Educational Resources Information Center

    Binnick, Robert I., Ed.; And Others

    The topics covered in this volume range over the entire field of linguistics. The authors are: A.L. Becker and D.G. Arms, W.R. Cantrall, G. Cohen, D.J. Darden, A. Davison, D. Elliott and others, J.E. Emonds, B. Fraser, G.M. Green, J.T. Heringer, L.R. Horn, L. Kartunnen, G. Lakoff, R. Lakoff, J.M. Lindholm, V.B. Makkai, J.L. Morgan, Y.C. Morin and…

  5. Summary of the 19th Joint EU-US Transport Task Force Workshop

    NASA Astrophysics Data System (ADS)

    Angioni, C.; Mantica, P.; Naulin, V.; Bourdelle, C.; Hidalgo, C.; Maggi, C. F.; Rice, J. E.; Sharapov, S. E.; 19th Joint EU-US Transport Task Force Workshop, the Participants to the

    2015-06-01

    This conference report summarizes the contributions to, and discussions at, the 19th Joint EU-US Transport Task Force workshop, held in Culham, UK, during 8-11 September 2014. The workshop was organized under six topics: momentum transport, energetic particles, challenges in modelling transport in ITER and JT60-SA, L-H transition, impurity transport and SOL transport. This report follows the same structure.

  6. The 7th International Cryocooler Conference

    NASA Astrophysics Data System (ADS)

    1993-04-01

    The partial contents of this document include the following: SDIO and Air Force Cryocooler Technology Developments at USAF Phillips Laboratory; JPL Cryocooler Development and Test Program Overview; Development and Demonstration of a Diaphragm Stirling 65 K Standard Spacecraft Cryocooler; Stirling Space Cooler; Thermal, Vibration, and Reliability Test Results for a Balanced 80 K Cryocooler; Spacecraft Cooler Characterization; Performance of a Long Life Reverse Brayton Cryocooler; SDI Cryocooler Producibility Program; Miniature Pulse Tube Cooler; Flow Patterns Intrinsic to the Pulse Tube Refrigerator; Experimental Investigation of the Regenerative Magnetic Refrigerator Operating Between 4.2 K and 1.8 K; A 4 K Gifford-McMahon Refrigerator for Radio Astronomy; A Stirling Cycle Cryocooler for 4 K Applications; Regenerator Performance and Refrigeration Mechanism for 4 K GM Refrigerator Using Rare Earth Compound Regenerator Materials; Superfluid Stirling Refrigerator with a Counterflow Regenerator; Graded and Nongraded Regenerator Performance; Evolution of the 10 K Periodic Sorption Refrigerator Concept; Development of a Periodic 10 K Sorption Cryocooler; Assessment of a Hydrogen Joule-Thomson Expander and Vanadium Hydride Sorption Beds for 20 K Cryocoolers; Design of a Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cryocooler; JT Cryostat with Liquid-Solid Cryogen Reservoir; Design of A Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cooler; and Phase Equilibria in Cryogenic Mixtures.

  7. Proceedings of the 7th International Cryocooler Conference, part 3

    NASA Astrophysics Data System (ADS)

    1993-04-01

    Partial contents include: SDIO and Air Force Cryocooler Technology Developments at USAF Phillips Laboratory; JPL Cryocooler Development and Test Program Overview; Development and Demonstration of a Diaphragm Stirling 65 K Standard Spacecraft Cryocooler; Stirling Space Cooler; Thermal, Vibration, and Reliability Test Results for a Balanced 80 K Cryocooler; Spacecraft Cooler Characterization; Performance of a Long Life Reverse Brayton Cryocooler; SDI Cryocooler Producibility Program; Miniature Pulse Tube Cooler; Flow Patterns Intrinsic to the Pulse Tube Refrigerator; Experimental Investigation of the Regenerative Magnetic Refrigerator Operating Between 4.2 K and 1.8 K; A 4 K Gifford-McMahon Refrigerator for Radio Astronomy; A Stirling Cycle Cryocooler for 4 K Applications; Regenerator Performance and Refrigeration Mechanism for 4 K GM Refrigerator Using Rare Earth Compound Regenerator Materials; Superfluid Stirling Refrigerator with a Counterflow Regenerator; Graded and Nongraded Regenerator Performance; Evolution of the 10 K Periodic Sorption Refrigerator Concept; Development of a Periodic 10 K Sorption Cryocooler; Assessment of a Hydrogen Joule-Thomson Expander and Vanadium Hydride Sorption Beds for 20 K Cryocoolers; Design of a Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cryocooler; JT Cryostat with Liquid-Solid Cryogen Reservoir; Design of A Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cooler; Phase Equilibria in Cryogenic Mixtures.

  8. Proceedings of the 7th International Cryocooler Conference, part 2

    NASA Astrophysics Data System (ADS)

    1993-04-01

    Partial contents include: SDIO and Air Force Cryocooler Technology Developments at USAF Phillips Laboratory; JPL Cryocooler Development and Test Program Overview; Development and Demonstration of a Diaphragm Stirling 65 K Standard Spacecraft Cryocooler; Stirling Space Cooler; Thermal, Vibration, and Reliability Test Results for a Balanced 80 K Cryocooler; Spacecraft Cooler Characterization; Performance of a Long Life Reverse Brayton Cryocooler; SDI Cryocooler Producibility Program; Miniature Pulse Tube Cooler; Flow Patterns Intrinsic to the Pulse Tube Refrigerator; Experimental Investigation of the Regenerative Magnetic Refrigerator Operating Between 4.2 K and 1.8 K; A 4 K Gifford-McMahon Refrigerator for Radio Astronomy; A Stirling Cycle Cryocooler for 4 K Applications; Regenerator Performance and Refrigeration Mechanism for 4 K GM Refrigerator Using Rare Earth Compound Regenerator Materials; Superfluid Stirling Refrigerator with a Counterflow Regenerator; Graded and Nongraded Regenerator Performance; Evolution of the 10 K Periodic Sorption Refrigerator Concept; Development of a Periodic 10 K Sorption Cryocooler; Assessment of a Hydrogen Joule-Thomson Expander and Vanadium Hydride Sorption Beds for 20 K Cryocoolers; Design of a Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cryocooler; JT Cryostat with Liquid-Solid Cryogen Reservoir; Design of A Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cooler; Phase Equilibria in Cryogenic Mixtures.

  9. Proceedings of the 7th International Cryocooler Conference, part 1

    NASA Astrophysics Data System (ADS)

    1993-04-01

    Partial contents include: SDIO and Air Force Cryocooler Technology Developments at USAF Phillips Laboratory; JPL Cryocooler Development and Test Program Overview; Development and Demonstration of a Diaphragm Stirling 65 K Standard Spacecraft Cryocooler; Stirling Space Cooler; Thermal, Vibration, and Reliability Test Results for a Balanced 80 K Cryocooler; Spacecraft Cooler Characterization; Performance of a Long Life Reverse Brayton Cryocooler; SDI Cryocooler Producibility Program; Miniature Pulse Tube Cooler; Flow Patterns Intrinsic to the Pulse Tube Refrigerator; Experimental Investigation of the Regenerative Magnetic Refrigerator Operating Between 4.2 K and 1.8 K; A 4 K Gifford-McMahon Refrigerator for Radio Astronomy; A Stirling Cycle Cryocooler for 4 K Applications; Regenerator Performance and Refrigeration Mechanism for 4 K GM Refrigerator Using Rare Earth Compound Regenerator Materials; Superfluid Stirling Refrigerator with a Counterflow Regenerator; Graded and Nongraded Regenerator Performance; Evolution of the 10 K Periodic Sorption Refrigerator Concept; Development of a Periodic 10 K Sorption Cryocooler; Assessment of a Hydrogen Joule-Thomson Expander and Vanadium Hydride Sorption Beds for 20 K Cryocoolers; Design of a Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cryocooler; JT Cryostat with Liquid-Solid Cryogen Reservoir; Design of A Metal Hydride Sorption Cryocooler System; Linear Compressor for JT Cooler; Phase Equilibria in Cryogenic Mixtures.

  10. Adult-onset type 1 diabetes patients display decreased IGRP-specific Tr1 cells in blood.

    PubMed

    Chujo, Daisuke; Nguyen, Thien-Son; Foucat, Emile; Blankenship, Derek; Banchereau, Jacques; Nepom, Gerald T; Chaussabel, Damien; Ueno, Hideki

    2015-12-01

    The breakdown of immune tolerance against islet antigens causes type 1 diabetes (T1D). The antigens associated with adult-onset T1D (AT1D) remain largely undefined. It is possible that AT1D patients display a unique type of CD4(+) T cells specific for a certain islet antigen. Here we analyzed the cytokine production profiles of CD4(+) helper T (Th) cells that are specific for three islet antigens; GAD65, preproinsulin, and IGRP in patients with AT1D, juvenile-onset T1D (JT1D), and age-, gender- and human leukocyte antigen (HLA)-matched control adults. While IGRP-specific Th cells in AT1D patients were dominantly Th1 cells, IGRP-specific Th cells in control adults and JT1D patients were dominantly Th2 and T regulatory type 1 (Tr1) cells. Notably, the frequency of IGRP-specific Tr1 cells was significantly lower in AT1D patients than in control adults and JT1D patients. In conclusion, our study suggests that IGRP-specific Th cells play a unique pathogenic role in AT1D. PMID:26341315

  11. 100 s extraction of negative ion beams by using actively temperature-controlled plasma grid

    SciTech Connect

    Kojima, A. Hanada, M.; Yoshida, M.; Tobari, H.; Kashiwagi, M.; Umeda, N.; Watanabe, K.; Grisham, L. R.

    2014-02-15

    Long pulse beam extraction with a current density of 120 A/m{sup 2} for 100 s has been achieved with a newly developed plasma grid (PG) for the JT-60SA negative ion source which is designed to produce high power and long pulse beams with a negative ion current of 130 A/m{sup 2} (22 A) and a pulse length of 100 s. The PG temperature is regulated by fluorinated fluids in order to keep the high PG temperature for the cesium-seeded negative ion production. The time constant for temperature controllability of the PG was measured to be below 10 s, which was mainly determined by the heat transfer coefficient of the fluorinated fluid. The measured decay time of the negative ion current extracted from the actively temperature-controlled PG was 430 s which was sufficient for the JT-60SA requirement, and much longer than that by inertial-cooling PG of 60 s. Obtained results of the long pulse capability are utilized to design the full size PG for the JT-60SA negative ion source.

  12. Symmetry-adapted excited states for the T1u⊗hg Jahn-Teller system

    NASA Astrophysics Data System (ADS)

    Qiu, Q. C.; Dunn, J. L.; Bates, C. A.

    2001-08-01

    Jahn-Teller (JT) systems typically contain a set of equivalent-energy wells in the lowest adiabatic potential-energy surface (APES). Quantum-mechanical tunneling between these wells (the dynamic JT effect) must be allowed for by taking appropriate symmetrized combinations of oscillator-type states associated with the wells. It is important to be able to describe the excited states of such systems for a number of reasons. One particular reason is that they are required for the calculation of second-order vibronic reduction factors, which in turn are useful for modeling experimental data using effective Hamiltonians. In this paper, projection-operator techniques are used to obtain general expressions for the symmetry-adapted excited states of the icosahedral T1u⊗hg JT system for the case of D5d minima in the APES. Analytical expressions for the states and their energies for one-phonon excitation are given explicitly. The energies of a selection of states with two-phonon excitations are also obtained and plotted. The results obtained in this paper are applicable to the C-60 molecule.

  13. Symmetry-adapted excited states for the T{sub 1u}(direct-product)h{sub g} Jahn-Teller system

    SciTech Connect

    Qiu, Q. C.; Dunn, J. L.; Bates, C. A.

    2001-08-15

    Jahn-Teller (JT) systems typically contain a set of equivalent-energy wells in the lowest adiabatic potential-energy surface (APES). Quantum-mechanical tunneling between these wells (the dynamic JT effect) must be allowed for by taking appropriate symmetrized combinations of oscillator-type states associated with the wells. It is important to be able to describe the excited states of such systems for a number of reasons. One particular reason is that they are required for the calculation of second-order vibronic reduction factors, which in turn are useful for modeling experimental data using effective Hamiltonians. In this paper, projection-operator techniques are used to obtain general expressions for the symmetry-adapted excited states of the icosahedral T{sub 1u}(direct-product)h{sub g} JT system for the case of D{sub 5d} minima in the APES. Analytical expressions for the states and their energies for one-phonon excitation are given explicitly. The energies of a selection of states with two-phonon excitations are also obtained and plotted. The results obtained in this paper are applicable to the C{sub 60}{sup -} molecule.

  14. The Liquefaction of Hydrogen and Helium Using Small Coolers

    SciTech Connect

    Green, Michael A.

    2006-02-12

    This report discusses the history of the liquefaction of hydrogen and helium using small coolers. This history dates form the 1960's when two stage GM coolers capable of reaching 7 K were used to liquefy helium and hydrogen by suing an added compressor and J-T circuit. Liquefaction using the added circuit failed to become mainstream because the J-T valve and heat exchanger clogged because of impurities in the gas being liquefied. Liquefaction using a GM cooler without an added J-T circuit proved to be difficult because the first stage was not used to pre-cool the gas coming to the second stage of the cooler. Once the gas being liquefied was pre-cooled using the cooler first stage, improvements in the liquefaction rates were noted. The advent of low temperature pulse tube cooler (down to 2.5 K) permitted one to achieve dramatic improvement is the liquefactions rates for helium. Similar but less dramatic improvements are expected for hydrogen as well. Using the PT-415 cooler, one can expect liquefaction rates of 15 to 20 liters per day for helium or hydrogen provided the heat leak into the cooler and the storage vessel is low. A hydrogen liquefier for MICE is presented at the end of this report.

  15. Operating Modes and Cooling Capabilities of the Flight ADR for the SXS Instrument on Astro-H

    NASA Technical Reports Server (NTRS)

    Shirron, Peter; Kimball, Mark; DiPirro, Michael

    2015-01-01

    The microcalorimeter array on the Soft X-ray Spectrometer instrument on Astro-H requires cooling to 50 mK, which will be accomplished by a 3-stage adiabatic demagnetization refrigerator (ADR). The ADR is surrounded by a cryogenic system consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and radiation shields within the cryostat. The unique ADR design allows the instrument to meet all of its science requirements using either the stored cryogen or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated in early 2014, and have since been extensively characterized and calibrated. At present, the four instruments are being integrated with the spacecraft in preparation for an early 2016 launch. This presentation summarizes the operation and performance of the ADR in all of its operating modes.

  16. Optical absorption and Raman spectroscopy of CuWO4

    NASA Astrophysics Data System (ADS)

    Ruiz-Fuertes, J.; Sanz-Ortiz, M. N.; González, J.; Rodríguez, F.; Segura, A.; Errandonea, D.

    2010-03-01

    The electronic absorption and Raman spectra of CuWO4 are studied as a function of pressure in the 0 - 20 GPa range. The below-gap absorption bands at 1.15, 1.38 and 1.56 eV correspond to Cu2+ d-transitions split by the Jahn-Teller distortion of CuO6 (Req = 1.98 Å Rax = 2.39 Å Qθ = 0.47 Å). Pressure induces a strong reduction of the JT distortion up to 10 GPa. Above this pressure we observe, by optical absorption and Raman spectroscopy, a first-order phase transition at 11 GPa with phase coexistence in the 10-12 GPa range, as it is confirmed by Raman spectroscopy. The absorption spectra suggest that two different Cu2+ sites are formed in the high pressure phase, each having rather different CuO6 distortion. The more JT distorted CuO6 centre is stable up to 20 GPa. Rather than JT reduction, pressure induces reorientations of the CuO6 octahedra in the high-pressure phase.

  17. Local Jahn-Teller distortions and orbital ordering in Ba3Cu1 +xSb2 -xO9 investigated by neutron scattering

    NASA Astrophysics Data System (ADS)

    Li, Bing; Louca, Despina; Feygenson, Mikhail; Brown, Craig M.; Copley, John R. D.; Iida, Kazuki

    2016-01-01

    A spin-orbital quantum liquid state is theoretically proposed in the honeycomb lattice of Ba3CuSb2O9 , enabled by dynamic short-range correlations between the spin and orbital degrees of freedom. Using neutron diffraction, the local atomic structure of Ba3Cu1 +xSb2 -xO9 at x =0 and 0.1 is obtained via the pair density function analysis. The results indicate that both compositions exhibit local Jahn-Teller (JT) distortions with the elongated CuO3 octahedral configuration. In Ba3Cu1.1Sb1.9O9 , JT ordering of the distorted CuO3 octahedra gives rise to the orthorhombic symmetry with ferro-orbital order. On the other hand, in Ba3CuSb2O9 , even though the CuO3 octahedra are JT distorted, there is no long-range ordering hence the symmetry is hexagonal. Furthermore, the local singlet excitation at 5.8 meV observed in Ba3CuSb2O9 below 50 K is absent in Ba3Cu1.1Sb1.9O9 . Instead, an excitation at 2.5 meV is observed in the latter, which is likely associated with short-range spin order.

  18. The Astro-H Soft X-ray Spectrometer (SXS)

    NASA Astrophysics Data System (ADS)

    Porter, F. Scott; Fujimoto, Ryuichi; Kelley, Richard L.; Kilbourne, Caroline A.; Mitsuda, Kazuhiasa; Ohashi, Takaya; Astro-H/SXS Collaboration

    2009-12-01

    The Soft-X-ray Spectrometer (SXS) is a high spectral resolution, cryogenic x-ray spectrometer that will fly on the Japan/U.S. Astro-H observatory in 2014. The SXS is composed of a 36 pixel, imaging, x-ray calorimeter array that will operate at 0.05 K utilizing a 2-stage adiabatic demagnetization refrigerator and a redundant pre-cooler design using both a 40 liter liquid helium tank and a 1.7 K Joule-Thomson (JT) cryocooler. Additional redundant Stirling cycle coolers provide pre-cooling for the (JT) and cool the outer thermal shields for the JT and the helium tank. The detector system, while similar to that flown on Suzaku, is composed of larger 0.81×0.81mm pixels, but has significantly better performance, currently predicted to be better than 4 eV FWHM at 6 keV with 95% quantum efficiency. This instrument is the result of a close collaboration between many institutions in the U.S. and Japan over the last 25 years. Here we will present an overview of the SXS instrument, the SXS cooling system, and recent laboratory improvements to the detector system.

  19. Development of mechanical cryocoolers for the cooling system of the Soft X-ray Spectrometer onboard Astro-H

    NASA Astrophysics Data System (ADS)

    ASTRO-H SXS Team; Sato, Yoichi; Shinozaki, Keisuke; Sugita, Hiroyuki; Mitsuda, Kazuhisa; Yamasaki, Noriko Y.; Takei, Yoh; Nakagawa, Takao; Fujimoto, Ryuichi; Murakami, Masahide; Tsunematsu, Shoji; Otsuka, Kiyomi; Yoshida, Seiji; Kanao, Kenichi; Narasaki, Katsuhiro

    2012-04-01

    Astro-H is the Japanese X-ray astronomy satellite planned for launch in 2014. The Soft X-ray Spectrometer (SXS) onboard Astro-H, is a high energy resolution spectrometer utilizing an X-ray micro-calorimeter array, which is operated at 50 mK by the ADR with the 30-L superfluid liquid helium (LHe). The mechanical cryocoolers, 4 K-class Joule Thomson (JT) cooler and 20 K-class double-staged Stirling (2ST) cooler are key components to achieve a LHe lifetime for over 3 years in orbit (5 years as a goal). Based on the existing cryocoolers onboard Akari (2006) and JEM/SMILES (2009), modifications for higher cooling power and reliability had been investigated. In the present development phase, the Engineering Models (EMs) of these upgraded cryocoolers are fabricated to carry out verification tests for cooling performance, mechanical performance and lifetime. Nominal cooling power of 200 mW at 20 K for the 2ST cooler and 40 mW at 4.5 K for the JT cooler were demonstrated with temperature and power margin. Mechanical performance test for the 2ST cooler units proves tolerability for pyro shock and vibration environment of the Astro-H criteria. Continuous running of the 4 K-class JT cooler combined with the 2ST precooler for lifetime test has achieved over 5000 h without any degradation of cooling performance.

  20. The Astro-H Soft X-ray Spectrometer (SXS)

    SciTech Connect

    Porter, F. Scott; Kelley, Richard L.; Kilbourne, Caroline A.; Fujimoto, Ryuichi; Mitsuda, Kazuhiasa; Ohashi, Takaya

    2009-12-16

    The Soft-X-ray Spectrometer (SXS) is a high spectral resolution, cryogenic x-ray spectrometer that will fly on the Japan/U.S. Astro-H observatory in 2014. The SXS is composed of a 36 pixel, imaging, x-ray calorimeter array that will operate at 0.05 K utilizing a 2-stage adiabatic demagnetization refrigerator and a redundant pre-cooler design using both a 40 liter liquid helium tank and a 1.7 K Joule-Thomson (JT) cryocooler. Additional redundant Stirling cycle coolers provide pre-cooling for the (JT) and cool the outer thermal shields for the JT and the helium tank. The detector system, while similar to that flown on Suzaku, is composed of larger 0.81x0.81mm pixels, but has significantly better performance, currently predicted to be better than 4 eV FWHM at 6 keV with 95% quantum efficiency. This instrument is the result of a close collaboration between many institutions in the U.S. and Japan over the last 25 years. Here we will present an overview of the SXS instrument, the SXS cooling system, and recent laboratory improvements to the detector system.0.

  1. Optimization of a Two-Stage Adr for the Soft X-Ray Spectrometer (sxs) Instrument on the Astro-H Mission

    NASA Astrophysics Data System (ADS)

    Shirron, P. J.; Kimball, M. O.; Wegel, D. C.; Miller, F. K.

    2010-04-01

    NASA/Goddard Space Flight Center has begun developing the Soft X-ray Spectrometer (SXS) instrument that will be flown on the Japanese Astro-H mission. The SXS's 36-pixel detector array will be cooled to 50 mK using a two-stage adiabatic demagnetization refrigerator (ADR). A complicating factor for its design is that the ADR will be integrated into a superfluid helium dewar at 1.3 K that will be coupled to a 1.8 K Joule-Thomson (JT) stage through a heat switch. When liquid helium is present, the coupling will be weak, and the JT stage will act primarily as a shield to reduce parasitic heat loads. When the liquid is depleted, the heat switch will couple more strongly so that the ADR can continue to operate using the JT stage as its heat sink. A two-stage ADR is the most mass efficient option and it has the operational flexibility to work well with a stored cryogen and a cryocooler. The stages are operated independently, and this opens up a very large parameter space for optimizing the design. This paper discusses the optimization process and most relevant trades considered in the design of the SXS ADR, and its expected performance.

  2. OPTIMIZATION OF A TWO-STAGE ADR FOR THE SOFT X-RAY SPECTROMETER (SXS) INSTRUMENT ON THE ASTRO-H MISSION

    SciTech Connect

    Shirron, P. J.; Kimball, M. O.; Wegel, D. C.

    2010-04-09

    NASA/Goddard Space Flight Center has begun developing the Soft X-ray Spectrometer (SXS) instrument that will be flown on the Japanese Astro-H mission. The SXS's 36-pixel detector array will be cooled to 50 mK using a two-stage adiabatic demagnetization refrigerator (ADR). A complicating factor for its design is that the ADR will be integrated into a superfluid helium dewar at 1.3 K that will be coupled to a 1.8 K Joule-Thomson (JT) stage through a heat switch. When liquid helium is present, the coupling will be weak, and the JT stage will act primarily as a shield to reduce parasitic heat loads. When the liquid is depleted, the heat switch will couple more strongly so that the ADR can continue to operate using the JT stage as its heat sink. A two-stage ADR is the most mass efficient option and it has the operational flexibility to work well with a stored cryogen and a cryocooler. The stages are operated independently, and this opens up a very large parameter space for optimizing the design. This paper discusses the optimization process and most relevant trades considered in the design of the SXS ADR, and its expected performance.

  3. Study of turboprop systems reliability and maintenance costs

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The overall reliability and maintenance costs (R&MC's) of past and current turboprop systems were examined. Maintenance cost drivers were found to be scheduled overhaul (40%), lack of modularity particularly in the propeller and reduction gearbox, and lack of inherent durability (reliability) of some parts. Comparisons were made between the 501-D13/54H60 turboprop system and the widely used JT8D turbofan. It was found that the total maintenance cost per flight hour of the turboprop was 75% higher than that of the JT8D turbofan. Part of this difference was due to propeller and gearbox costs being higher than those of the fan and reverser, but most of the difference was in the engine core where the older technology turboprop core maintenance costs were nearly 70 percent higher than for the turbofan. The estimated maintenance cost of both the advanced turboprop and advanced turbofan were less than the JT8D. The conclusion was that an advanced turboprop and an advanced turbofan, using similar cores, will have very competitive maintenance costs per flight hour.

  4. 100 s extraction of negative ion beams by using actively temperature-controlled plasma grid.

    PubMed

    Kojima, A; Hanada, M; Yoshida, M; Tobari, H; Kashiwagi, M; Umeda, N; Watanabe, K; Grisham, L R

    2014-02-01

    Long pulse beam extraction with a current density of 120 A/m(2) for 100 s has been achieved with a newly developed plasma grid (PG) for the JT-60SA negative ion source which is designed to produce high power and long pulse beams with a negative ion current of 130 A/m(2) (22 A) and a pulse length of 100 s. The PG temperature is regulated by fluorinated fluids in order to keep the high PG temperature for the cesium-seeded negative ion production. The time constant for temperature controllability of the PG was measured to be below 10 s, which was mainly determined by the heat transfer coefficient of the fluorinated fluid. The measured decay time of the negative ion current extracted from the actively temperature-controlled PG was 430 s which was sufficient for the JT-60SA requirement, and much longer than that by inertial-cooling PG of 60 s. Obtained results of the long pulse capability are utilized to design the full size PG for the JT-60SA negative ion source. PMID:24593589

  5. Investigation of pressure drop in capillary tube for mixed refrigerant Joule-Thomson cryocooler

    SciTech Connect

    Ardhapurkar, P. M.; Sridharan, Arunkumar; Atrey, M. D.

    2014-01-29

    A capillary tube is commonly used in small capacity refrigeration and air-conditioning systems. It is also a preferred expansion device in mixed refrigerant Joule-Thomson (MR J-T) cryocoolers, since it is inexpensive and simple in configuration. However, the flow inside a capillary tube is complex, since flashing process that occurs in case of refrigeration and air-conditioning systems is metastable. A mixture of refrigerants such as nitrogen, methane, ethane, propane and iso-butane expands below its inversion temperature in the capillary tube of MR J-T cryocooler and reaches cryogenic temperature. The mass flow rate of refrigerant mixture circulating through capillary tube depends on the pressure difference across it. There are many empirical correlations which predict pressure drop across the capillary tube. However, they have not been tested for refrigerant mixtures and for operating conditions of the cryocooler. The present paper assesses the existing empirical correlations for predicting overall pressure drop across the capillary tube for the MR J-T cryocooler. The empirical correlations refer to homogeneous as well as separated flow models. Experiments are carried out to measure the overall pressure drop across the capillary tube for the cooler. Three different compositions of refrigerant mixture are used to study the pressure drop variations. The predicted overall pressure drop across the capillary tube is compared with the experimentally obtained value. The predictions obtained using homogeneous model show better match with the experimental results compared to separated flow models.

  6. Quadratic coupling treatment of the Jahn-Teller effect in the triply-degenerate electronic state of CH4+: Can one account for floppiness?

    NASA Astrophysics Data System (ADS)

    Mondal, T.; Varandas, A. J. C.

    2012-12-01

    The Jahn-Teller (JT) coupling effects in the triply degenerate ground electronic state of methane radical cation are investigated theoretically within a quadratic vibronic coupling approach. The underlying potential energy surfaces over the two-dimensional space of nuclear coordinates, subject to the T2 ⊗ (e + t2 + t2) Jahn-Teller effect, are established from extensive ab initio calculations using the multi-reference configuration interaction method and then employed to determine the various parameters of a diabatic Hamiltonian of this system. Our previous investigation [T. Mondal and A. J. C. Varandas, J. Chem. Phys. 135, 174304 (2011), 10.1063/1.3658641], relying on the linear vibronic coupling approach augmented by only a diagonal second-order term of the totally symmetric mode, are extended here by including all possible quadratic coupling constants of JT active e and t2 modes. Inclusion of these quadratic couplings is found to be important to reproduce correctly the broad vibrational structure and for a better description of dynamical JT effect in the first vibronic band of this radical cation. The impact of large amplitude motions (which are responsible for floppiness of the molecule) on the vibronic structure and dynamics of the first photoelectron band have been examined via readjustment of their linear coupling parameters up to ±10%.

  7. Single-hole dynamics in the t-J model on a square lattice

    NASA Astrophysics Data System (ADS)

    Brunner, Michael; Assaad, Fakher F.; Muramatsu, Alejandro

    2000-12-01

    We present quantum Monte Carlo (QMC) simulations for a single hole in a t-J model from J=0.4t to J=4t on square lattices with up to 24×24 sites. The lower edge of the spectrum is directly extracted from the imaginary time Green's function. In agreement with earlier calculations, we find flat bands around (0,+/-π), (+/-π,0) and the minimum of the dispersion at (+/-π/2,+/-π/2). For small J, both self-consistent Born approximation and series expansions give a bandwidth for the lower edge of the spectrum in agreement with the simulations, whereas for J/t>1, only series expansions agree quantitatively with our QMC results. This band corresponds to a coherent quasiparticle. This is shown by a finite-size scaling of the quasiparticle weight Z(k-->) that leads to a finite result in the thermodynamic limit for the considered values of J/t. The spectral function A(k-->,ω) is obtained from the imaginary time Green's function via the maximum entropy method. Resonances above the lowest edge of the spectrum are identified, whose J dependence is quantitatively described by string excitations up to J/t=2.

  8. Operating modes and cooling capabilities of the 3-stage ADR developed for the Soft-X-ray Spectrometer instrument on Astro-H

    NASA Astrophysics Data System (ADS)

    Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theodore; DiPirro, Michael J.; Letmate, Richard V.; Sampson, Michael A.; Bialas, Tom G.; Sneiderman, Gary A.; Porter, Frederick S.; Kelley, Richard L.

    2016-03-01

    A 3-stage adiabatic demagnetization refrigerator (ADR) (Shirron et al., 2012) is used on the Soft X-ray Spectrometer instrument (Mitsuda et al., 2010) on Astro-H (Takahashi et al., 2010) [3] to cool a 6 × 6 array of X-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system (Fujimoto et al., 2010) consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes.

  9. Fast Super-Resolution Imaging with Ultra-High Labeling Density Achieved by Joint Tagging Super-Resolution Optical Fluctuation Imaging

    PubMed Central

    Zeng, Zhiping; Chen, Xuanze; Wang, Hening; Huang, Ning; Shan, Chunyan; Zhang, Hao; Teng, Junlin; Xi, Peng

    2015-01-01

    Previous stochastic localization-based super-resolution techniques are largely limited by the labeling density and the fidelity to the morphology of specimen. We report on an optical super-resolution imaging scheme implementing joint tagging using multiple fluorescent blinking dyes associated with super-resolution optical fluctuation imaging (JT-SOFI), achieving ultra-high labeling density super-resolution imaging. To demonstrate the feasibility of JT-SOFI, quantum dots with different emission spectra were jointly labeled to the tubulin in COS7 cells, creating ultra-high density labeling. After analyzing and combining the fluorescence intermittency images emanating from spectrally resolved quantum dots, the microtubule networks are capable of being investigated with high fidelity and remarkably enhanced contrast at sub-diffraction resolution. The spectral separation also significantly decreased the frame number required for SOFI, enabling fast super-resolution microscopy through simultaneous data acquisition. As the joint-tagging scheme can decrease the labeling density in each spectral channel, thereby bring it closer to single-molecule state, we can faithfully reconstruct the continuous microtubule structure with high resolution through collection of only 100 frames per channel. The improved continuity of the microtubule structure is quantitatively validated with image skeletonization, thus demonstrating the advantage of JT-SOFI over other localization-based super-resolution methods. PMID:25665878

  10. Fast super-resolution imaging with ultra-high labeling density achieved by joint tagging super-resolution optical fluctuation imaging.

    PubMed

    Zeng, Zhiping; Chen, Xuanze; Wang, Hening; Huang, Ning; Shan, Chunyan; Zhang, Hao; Teng, Junlin; Xi, Peng

    2015-01-01

    Previous stochastic localization-based super-resolution techniques are largely limited by the labeling density and the fidelity to the morphology of specimen. We report on an optical super-resolution imaging scheme implementing joint tagging using multiple fluorescent blinking dyes associated with super-resolution optical fluctuation imaging (JT-SOFI), achieving ultra-high labeling density super-resolution imaging. To demonstrate the feasibility of JT-SOFI, quantum dots with different emission spectra were jointly labeled to the tubulin in COS7 cells, creating ultra-high density labeling. After analyzing and combining the fluorescence intermittency images emanating from spectrally resolved quantum dots, the microtubule networks are capable of being investigated with high fidelity and remarkably enhanced contrast at sub-diffraction resolution. The spectral separation also significantly decreased the frame number required for SOFI, enabling fast super-resolution microscopy through simultaneous data acquisition. As the joint-tagging scheme can decrease the labeling density in each spectral channel, thereby bring it closer to single-molecule state, we can faithfully reconstruct the continuous microtubule structure with high resolution through collection of only 100 frames per channel. The improved continuity of the microtubule structure is quantitatively validated with image skeletonization, thus demonstrating the advantage of JT-SOFI over other localization-based super-resolution methods. PMID:25665878

  11. Improving Control in a Joule-Thomson Refrigerator

    NASA Technical Reports Server (NTRS)

    Borders, James; Pearson, David; Prina, Mauro

    2005-01-01

    A report discusses a modified design of a Joule-Thomson (JT) refrigerator under development to be incorporated into scientific instrumentation aboard a spacecraft. In most other JT refrigerators (including common household refrigerators), the temperature of the evaporator (the cold stage) is kept within a desired narrow range by turning a compressor on and off as needed. This mode of control is inadequate for the present refrigerator because a JT-refrigerator compressor performs poorly when the flow from its evaporator varies substantially, and this refrigerator is required to maintain adequate cooling power. The proposed design modifications include changes in the arrangement of heat exchangers, addition of a clamp that would afford a controlled heat leak from a warmer to a cooler stage to smooth out temperature fluctuations in the cooler stage, and incorporation of a proportional + integral + derivative (PID) control system that would regulate the heat leak to maintain the temperature of the evaporator within a desired narrow range while keeping the amount of liquid in the evaporator within a very narrow range in order to optimize the performance of the compressor. Novelty lies in combining the temperature- and cooling-power-regulating controls into a single control system.

  12. Hot isostatically pressed manufacture of high strength MERL 76 disk and seal shapes

    NASA Technical Reports Server (NTRS)

    Eng, R. D.; Evans, D. J.

    1982-01-01

    The feasibility of using MERL 76, an advanced high strength direct hot isostatic pressed powder metallurgy superalloy, as a full scale component in a high technology, long life, commercial turbine engine were demonstrated. The component was a JT9D first stage turbine disk. The JT9D disk rim temperature capability was increased by at least 22 C and the weight of JT9D high pressure turbine rotating components was reduced by at least 35 pounds by replacement of forged Superwaspaloy components with hot isostatic pressed (HIP) MERL 76 components. The process control plan and acceptance criteria for manufacture of MERL 76 HIP consolidated components were generated. Disk components were manufactured for spin/burst rig test, experimental engine tests, and design data generation, which established lower design properties including tensile, stress-rupture, 0.2% creep and notched (Kt = 2.5) low cycle fatigue properties, Sonntag, fatigue crack propagation, and low cycle fatigue crack threshold data. Direct HIP MERL 76, when compared to conventionally forged Superwaspaloy, is demonstrated to be superior in mechanical properties, increased rim temperature capability, reduced component weight, and reduced material cost by at least 30% based on 1980 costs.

  13. NGST Advanced Cryocooler Technology Development Program (ACTDP) Cooler System

    NASA Astrophysics Data System (ADS)

    Durand, D.; Raab, J.; Colbert, R.; Michaelian, M.; Nguyen, T.; Petach, M.; Tward, E.

    2006-04-01

    The NGST ACTDP cooler features a 5-6 K Joule-Thomson (JT) cooler pre-cooled by a three-stage Pulse Tube (PT) cryocooler. Our design provides remote cooling of ~60 mW at 5 to 6 K and, optionally, remote cooling at 18 K. The NGST ACTDP cooler is being developed under contract with the Jet Propulsion Laboratory to enable active cooling of instruments including large space telescopes, in particular the Mid InfraRed Instrument (MIRI) of the James Webb Space Telescope (JWST). This paper describes the design of the NGST ACTDP cooler and presents test results, including the integrated tests of the two major subsystems making up the thermal-mechanical cryocooler, the closed loop JT cooler and the PT pre-cooler. Both the JT and PT subsystems have been demonstrated to provide the cooling required for MIRI in laboratory tests using flight like hardware with excess capacity. These tests enable a reliable projection of the total electrical power of the NGST MIRI cooler of 200-296 W for steady state operation under end of life conditions, depending on the margins added to the thermal loads and parasitics. NGST's design offers a low risk approach to providing cooling of MIRI making maximum use of flight proven hardware.

  14. Photophysics of barrelene: The Jahn-Teller and pseudo-Jahn-Teller effects

    NASA Astrophysics Data System (ADS)

    Ghanta, Susanta

    2016-04-01

    The static and dynamic aspects of Jahn-Teller(JT) and pseudo-Jahn-Teller(PJT) interactions between ground (X˜2A2‧) and first three excited electronic states (A˜2E‧ , B˜2E″ and C˜2A‧1) of bicyclo- [2,2,2]-octa-2,5,7-triene (barrelene) radical cation (Bl+) are theoretically investigated here. This belongs to the (E + E) ⊗ e and (E + A) ⊗ e JT-PJT class of compounds as described by the symmetry of the electronic states and the molecular point group. The complex vibronic dynamics on the coupled electronic states of the cation is simulated by both time-independent and time-dependent wave packet propagation method using multi configuration time-dependent Hartree scheme. The JT effects in the A˜ and B˜ electronic states and the PJT coupling between the B˜ and C˜ electronic states of Bl+ are found very strong. The final theoretical results are compared with the experimental results.

  15. p-Cymene pathway in Pseudomonas putida: selective enrichment of defective mutants by using halogenated substrate analogs.

    PubMed Central

    Wigmore, G J; Ribbons, D W

    1980-01-01

    Several classes of mutants of Pseudomonas putida (JT810) defective in the utilization of p-cymene as sole carbon source have been isolated. Selective enrichment of the mutants and for strains putatively cured of a degradative plasmid was achieved by incubation of cells in minimal growth media containing p-cymene (or p-cumate) and various halogenated analogs of the growth substrates or pathway intermediates. Analogs which led to successful enrichments included: p-chlorotoluene, p-bromotoluene, alpha-chloro-p-xylene, and p-iodobenzoate. A mutant strain, PpJT811, constitutive for the p-cymene pathway gave significantly greater enrichments of defective mutants than the wild-type parent PpJT810 after incubation with the halogenated analogs. It is suggested that the defective mutants are enriched because of the genetic alterations they possess, which confer immunity to a lethal synthesis performed by transformation of the analogs in clones possessing an intact p-cymene pathway. A nomenclature for the genetic organization of p-cymene pathway is described. PMID:7204334

  16. Development of imaging bolometers for magnetic fusion reactors (invited)

    SciTech Connect

    Peterson, Byron J.; Parchamy, Homaira; Ashikawa, Naoko; Kawashima, Hisato; Konoshima, Shigeru; Kostryukov, Artem Yu.; Miroshnikov, Igor V.; Seo, Dongcheol; Omori, T.

    2008-10-15

    Imaging bolometers utilize an infrared (IR) video camera to measure the change in temperature of a thin foil exposed to the plasma radiation, thereby avoiding the risks of conventional resistive bolometers related to electric cabling and vacuum feedthroughs in a reactor environment. A prototype of the IR imaging video bolometer (IRVB) has been installed and operated on the JT-60U tokamak demonstrating its applicability to a reactor environment and its ability to provide two-dimensional measurements of the radiation emissivity in a poloidal cross section. In this paper we review this development and present the first results of an upgraded version of this IRVB on JT-60U. This upgrade utilizes a state-of-the-art IR camera (FLIR/Indigo Phoenix-InSb) (3-5 {mu}m, 256x360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF{sub 2} optics and an aluminum mirror. The IRVB foil is 7 cmx9 cmx5 {mu}m tantalum. A noise equivalent power density of 300 {mu}W/cm{sup 2} is achieved with 40x24 channels and a time response of 10 ms or 23 {mu}W/cm{sup 2} for 16x12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U.

  17. Development of imaging bolometers for magnetic fusion reactors (invited).

    PubMed

    Peterson, Byron J; Parchamy, Homaira; Ashikawa, Naoko; Kawashima, Hisato; Konoshima, Shigeru; Kostryukov, Artem Yu; Miroshnikov, Igor V; Seo, Dongcheol; Omori, T

    2008-10-01

    Imaging bolometers utilize an infrared (IR) video camera to measure the change in temperature of a thin foil exposed to the plasma radiation, thereby avoiding the risks of conventional resistive bolometers related to electric cabling and vacuum feedthroughs in a reactor environment. A prototype of the IR imaging video bolometer (IRVB) has been installed and operated on the JT-60U tokamak demonstrating its applicability to a reactor environment and its ability to provide two-dimensional measurements of the radiation emissivity in a poloidal cross section. In this paper we review this development and present the first results of an upgraded version of this IRVB on JT-60U. This upgrade utilizes a state-of-the-art IR camera (FLIR/Indigo Phoenix-InSb) (3-5 microm, 256 x 360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF(2) optics and an aluminum mirror. The IRVB foil is 7 cm x 9 cm x 5 microm tantalum. A noise equivalent power density of 300 microW/cm(2) is achieved with 40 x 24 channels and a time response of 10 ms or 23 microW/cm(2) for 16 x 12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U. PMID:19044463

  18. Local Lattice Distortions in LiNiO_2, a system with spin and orbital frustration

    NASA Astrophysics Data System (ADS)

    Egami, Takeshi; Piekarz, Przemek; Proffen, Thomas; Louca, Despina; Ghorayeb, Andre

    2003-03-01

    Ni ions in LiNiO2 form a layer of a triangular lattice, so that both spins and orbital moments are geometrically frustrated from ordering, and the interplay of the two levels of frustration creates unusual magnetic behavior. The key to understanding this complex system is to find the "weakest link" that becomes compromised by the competing interactions. We studied the atomic structure of this system with the pulsed neutron pair-density function (PDF) analysis performed with the NPDF spectrometer of the Lujan Center of Los Alamos National Laboratory. We find that Ni ions are always locally Jahn-Teller (JT) distorted, while the orientational correlations among the local JT distortion changes gradually with temperature. The temperature scale of the change is about 300 K. Thus the weakest link in the orbital ordering is the elastic interaction among the local JT centers, which leads to short-range orbital ordering. The magnetic interaction follows the local orbital ordering and produces the observed effects.

  19. Identification and genetic characterization of porcine hemagglutinating encephalomyelitis virus from domestic piglets in China.

    PubMed

    Dong, Bo; Lu, Huijun; Zhao, Kui; Liu, Wenfeng; Gao, Wei; Lan, Yungang; Zhao, Jiakuan; Tang, Bo; Song, Deguang; He, Wenqi; Gao, Feng

    2014-09-01

    In this study, we investigated an acute outbreak of porcine hemagglutinating encephalomyelitis on a farm of 127 pigs in Jilin province, China. Porcine hemagglutinating encephalomyelitis virus (PHEV) was detected in suckling and weaning pigs by RT-PCR assays. Coronavirus-like particles were observed by electron microscopy. The virus isolate was designated PHEV-JT06. The clinical signs, nervous symptoms and positive labeling of neurons in the cerebral cortex with an immunohistochemical stain in PHEV-JT06-infected BALB/c mice supported the diagnosis of PHEV infection. The five full-length PHEV-JT06 structural genes were cloned, sequenced and analyzed. Phylogenetic studies based on the nucleotide and amino acid sequences of the five genes in the outbreak showed that PHEV remained genetically stable. PHEV shares 95.3-99.3% amino acid sequence identity with American strains (AY078417), suggesting that the Chinese isolate is most likely derived from the North American strain. Additionally, PHEV, HCoV-OC43 and BCoV were genetically close. These results may provide some insights into the genotype of the etiological agent responsible for the porcine hemagglutinating encephalomyelitis outbreak and could also provide a comparative view of the genomics of the five structural proteins of PHEV. PMID:24756345

  20. Visualization of the solid-liquid equilibria for non-flammable mixed refrigerants

    NASA Astrophysics Data System (ADS)

    Lee, Cheonkyu; Yoo, Junghyun; Lee, Jisung; Jeong, Sangkwon

    2016-04-01

    Non-flammable mixed refrigerant (NF-MR) Joule Thomson (J-T) refrigerators have desirable characteristics and wide cooling temperature range compared to those of pure J-T refrigerators. However, the operating challenge due to freezing is a critical issue to realize this type of refrigerator. In this paper, the solid-liquid phase equilibria (i.e. freezing point) of the NF-MR which is composed of Argon (Ar), R14 (CF4), and R218 (C3F8), has been experimentally investigated by a visualized apparatus. The accuracy of the apparatus is experimentally verified with pure refrigerants and selected binary mixed refrigerants. Freezing points of the ternary NF-MRs have been measured with the molar compositions from 0.1 to 0.8 for each component. Each test result is simultaneously acquired by a camcorder for visual inspection and temperature measurement during a warming process. Experimental results reveal that the specific MR, with R14 molar composition higher than 0.4, can achieve remarkably low freezing temperature even below 77 K. These unusual freezing point depression characteristics of the MR can be a useful information for designing a cryogenic MR J-T refrigerator to reach temperatures less than 77 K.