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1

The KATRIN Experiment  

E-print Network

The KArlsruhe TRitium Neutrino mass experiment, KATRIN, aims to search for the mass of the electron neutrino with a sensitivity of 0.2 eV/c^2 (90% C.L.) and a detection limit of 0.35 eV/c^2 (5 sigma). Both a positive or a negative result will have far reaching implications for cosmology and the standard model of particle physics and will give new input for astroparticle physics and cosmology. The major components of KATRIN are being set up at the Karlsruhe Institut of Technology in Karlsruhe, Germany, and test measurements of the individual components have started. Data taking with tritium is scheduled to start in 2012.

Beck, Marucs

2009-01-01

2

The KATRIN Experiment  

E-print Network

The KArlsruhe TRitium Neutrino mass experiment, KATRIN, aims to search for the mass of the electron neutrino with a sensitivity of 0.2 eV/c^2 (90% C.L.) and a detection limit of 0.35 eV/c^2 (5 sigma). Both a positive or a negative result will have far reaching implications for cosmology and the standard model of particle physics and will give new input for astroparticle physics and cosmology. The major components of KATRIN are being set up at the Karlsruhe Institut of Technology in Karlsruhe, Germany, and test measurements of the individual components have started. Data taking with tritium is scheduled to start in 2012.

Marcus Beck

2009-10-26

3

JT-60 Control System  

SciTech Connect

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has features of a functionally distributed and hierarchical structure, using CAMAC interfaces initially, which have been replaced by versatile module Europe (VME)-bus interfaces, and a protective interlock system composed of both software and hard-wired interlock logics.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.

Yonekawa, I.; Kawamata, Y.; Totsuka, T.; Akasaka, H.; Sueoka, M.; Kurihara, K.; Kimura, T. [Japan Atomic Energy Research Institute (Japan)

2002-09-15

4

Katrin Beyer / EESD / katrin.beyer@epfl.ch 129 May 2013 CoMa-WallS Project  

E-print Network

/ katrin.beyer@epfl.ch 429 May 2013 Concrete-Masonry Wall Structure (CoMa-WallS) Shake-table test #12;Katrin Beyer / EESD / katrin.beyer@epfl.ch 529 May 2013 Concrete-Masonry Wall Structure (Co procedure (cutting, burning) · Perforation at small scale with similar void ratio, similar effective width

5

Tools for electromagnetic field simulation in the KATRIN experiment  

E-print Network

The Karlsruhe Tritium Neutrino (KATRIN) experiment is a tritium beta decay experiment designed to make a direct, model independent measurement of the electron neutrino mass. To accomplish this task, the experiment employs ...

Corona, Thomas Joseph

2009-01-01

6

The penning trap electron gun for the KATRIN experiment  

E-print Network

The KArlsruhe TRitium Neutrino experiment (KATRIN) is currently in under construction, with plans to be activated in 2010. The experiment will measure the energy of electrons recoiling from the three body beta decay of ...

Trowbridge, Sarah Nicole

2008-01-01

7

Electron line shape of the KATRIN monitor spectrometer  

NASA Astrophysics Data System (ADS)

Conversion electrons emitted from 83mKr implanted into a solid substrate will serve as a powerful tool for monitoring of the energy scale stability in the KATRIN neutrino experiment. An appropriate description of the conversion line shape is essential to determine the energy of the emitted electrons. It is shown that the Doniach-Šunji? line shape gives a significantly better fit to the conversion electron spectra than the previously used double Voigt model. The electron spectra were obtained with the KATRIN MAC-E filter monitor spectrometer.

Slezák, M.; Bauer, S.; Dragoun, O.; Erhard, M.; Schlösser, K.; Špalek, A.; Vénos, D.; Zbo?il, M.

2013-12-01

8

EM field, tracking and scattering simulations for the KATRIN experiment  

NASA Astrophysics Data System (ADS)

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.

Glück, Ferenc; KATRIN Collaboration

2013-02-01

9

Computational Forensics: Towards Hybrid-Intelligent Crime Investigation Katrin Franke  

E-print Network

Computational Forensics: Towards Hybrid-Intelligent Crime Investigation Katrin Franke Norwegian procedures for crime investigation, prosecution and the enforcement of law. Computer-based methods have also, mathematical, statistical and computer science methods have found extensive application in devel- oping new

10

CONVERSATIONAL SPEECH RECOGNITION USING ACOUSTIC AND ARTICULATORY Katrin Kirchhoff  

E-print Network

CONVERSATIONAL SPEECH RECOGNITION USING ACOUSTIC AND ARTICULATORY INPUT Katrin Kirchhoff Department task. In this study we extend this approach to large­vocabulary conversational speech recognition using in speech recognition is increasingly gaining popularity. An ensemble of recognizers with different

Kirchhoff, Katrin

11

JT8D engine performance retention  

NASA Technical Reports Server (NTRS)

The attractive performance retention characteristics of the JT8D engine are described. Because of its moderate bypass ratio and turbine temperature, and stiff structural design, the performance retention versus flight cycles of the JT8D engine sets a standard that is difficult for other engines to equal. In addition, the significant benefits of refurbishment of the JT8D engine are presented. Cold section refurbishment offers thrust specific fuel consumption improvements of up to 2 percent and payback in less than a year, making a very attractive investment option for the airlines.

James, A. D.; Weisel, D. R.

1981-01-01

12

Progress of the JT-60SA project  

NASA Astrophysics Data System (ADS)

The JT-60SA project implemented by Japan and Europe is progressing on schedule towards the first plasma in March 2019. After careful R&D, procurements of the major components have entered their manufacturing stages. In parallel, disassembly of JT-60U has been completed on time, and the JT-60SA tokamak assembly is expected to start in January 2013. The JT-60SA device, a highly shaped large superconducting tokamak with a variety of plasma control actuators, has been designed in order to contribute to ITER and to complement ITER in all the major areas of fusion plasma development necessary to decide DEMO reactor construction. Detailed assessments and prediction studies of the JT-60SA plasma regimes have confirmed these capabilities: using ITER- and DEMO-relevant plasma regimes, heating conditions, and its sufficiently long discharge duration, JT-60SA enables studies on magnetohydrodynamic stability at high beta, heat/particle/momentum transport, high-energy ion physics, pedestal physics including edge localized mode control, and divertor physics. By integrating these studies, the project provides ‘simultaneous and steady-state sustainment of the key performance characteristics required for DEMO’ with integrated control scenario development.

Kamada, Y.; Barabaschi, P.; Ishida, S.; the JT-60SA Team; Research Plan Contributors, JT-60SA

2013-10-01

13

The KATRIN pre-spectrometer at reduced filter energy  

NASA Astrophysics Data System (ADS)

The Karlsruhe Tritium Neutrino (KATRIN) experiment will determine the mass of the electron neutrino with a sensitivity of 0.2 eV (90% CL) via a measurement of the ?-spectrum of gaseous tritium near its endpoint of E0 = 18.57 keV. An ultra-low background of about b = 10 mHz is among the requirements on reaching this sensitivity. In the KATRIN main beam line, two spectrometers of MAC-E filter type are used in tandem configuration. This setup, however, produces a Penning trap, which could lead to increased background. We have performed test measurements showing that the filter energy of the pre-spectrometer can be reduced by several keV in order to diminish this trap. These measurements were analyzed with the help of a complex computer simulation, modeling multiple electron reflections from both the detector and the photoelectric electron source used in our test setup.

Prall, M.; Renschler, P.; Glück, F.; Beglarian, A.; Bichsel, H.; Bornschein, L.; Chaoui, Z.; Drexlin, G.; Fränkle, F.; Görhardt, S.; Mertens, S.; Steidl, M.; Thümmler, Th; Wüstling, S.; Weinheimer, C.; Zadorozhny, S.

2012-07-01

14

A review of the characterization KATRIN detector section  

NASA Astrophysics Data System (ADS)

A short review of the Karlsruhe Tritium Neutrino (KATRIN) experiment's detector section and preliminary data from the characterization of the focal plane detector will be presented. KATRIN's goal is to attain a mass sensitivity of .2 eV by measuring the shape of the tritium beta decay spectrum at the end point. There are essentially three main sections to the KATRIN's detector: a tritium source, spectrometers, and a detector section. The beta decay electrons are emitted from a gaseous tritium source and magnetically guided to a pre-spectrometer then to the main spectrometer. The pre-spectrometer removes the electrons 100 eV below the endpoint energy. The main spectrometer, with an energy resolution of .93 eV, allows us to achieve the .2 eV sensitivity. Finally a silicon PIN diode array detects the analyzed electrons. The array is 94 millimeters in diameter, 500 microns thick and segmented into 144 sections of equal area. I will discuss the performance front-end electronics and of the characterization of the array with a precision electron gun.

Wall, Brandon

2008-10-01

15

Radon induced background processes in the KATRIN pre-spectrometer  

NASA Astrophysics Data System (ADS)

The KArlsruhe TRItium Neutrino (KATRIN) experiment is a next generation, model independent, large scale tritium ?-decay experiment to determine the effective electron anti-neutrino mass by investigating the kinematics of tritium ?-decay with a sensitivity of 200 meV/c 2 using the MAC-E filter technique. In order to reach this sensitivity, a low background level of 10 -2 counts per second (cps) is required. This paper describes how the decay of radon in a MAC-E filter generates background events, based on measurements performed at the KATRIN pre-spectrometer test setup. Radon (Rn) atoms, which emanate from materials inside the vacuum region of the KATRIN spectrometers, are able to penetrate deep into the magnetic flux tube so that the ?-decay of Rn contributes to the background. Of particular importance are electrons emitted in processes accompanying the Rn ?-decay, such as shake-off, internal conversion of excited levels in the Rn daughter atoms and Auger electrons. While low-energy electrons (<100 eV) directly contribute to the background in the signal region, higher energy electrons can be stored magnetically inside the volume of the spectrometer. Depending on their initial energy, they are able to create thousands of secondary electrons via subsequent ionization processes with residual gas molecules and, since the detector is not able to distinguish these secondary electrons from the signal electrons, an increased background rate over an extended period of time is generated.

Fränkle, F. M.; Bornschein, L.; Drexlin, G.; Glück, F.; Görhardt, S.; Käfer, W.; Mertens, S.; Wandkowsky, N.; Wolf, J.

2011-10-01

16

Wall conditioning in JT-60  

NASA Astrophysics Data System (ADS)

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 ?m 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.

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

17

The JT8D and JT9D engine component improvement: Performance improvement program  

NASA Technical Reports Server (NTRS)

The NASA sponsored Engine Component Improvement - Performance Improvement Program at Pratt & Whitney Aircraft advanced the state of the art of thermal barrier coatings and ceramic seal systems, demonstrated the practicality of an advanced turbine clearance control system and an advanced fan design in the JT9D engine, and demonstrated the advantages of modern cooling, sealing, and aerodynamic designs in the high pressure turbine and compressor of the JT8D engine. Several of these improvements are already in airline service in JT8D and JT9D engines, and others will enter service soon in advanced models of these engines. In addition, the technology advances are being transferred to completely new engine configurations, the PW2037 engine and the NASA sponsored Energy Efficient Engine.

Gaffin, W. O.

1982-01-01

18

KATRIN: an experiment to measure the neutrino mass  

E-print Network

KATRIN is a very large scale tritium-beta-decay experiment to determine the mass of the neutrino. It is presently under construction at the Forschungszentrum Karlsruhe, and makes use of the Tritium Laboratory built there for the ITER project. The combination of a very large retarding-potential electrostatic-magnetic spectrometer and an intense gaseous molecular tritium source makes possible a sensitivity to neutrino mass of 0.2 eV, about an order of magnitude below present laboratory limits. The measurement is kinematic and independent of whether the neutrino is Dirac or Majorana. The status of the project is summarized briefly in this report.

Robertson, R G H

2007-01-01

19

Absolute neutrino mass scale determination with the KATRIN experiment  

SciTech Connect

The aim of the KArlsruhe TRItium Neutrino experiment KATRIN is the direct and model independent determination of the absolute neutrino mass scale down to 0.2 eV. For this purpose, the integral electron energy spectrum will be measured close to the endpoint of molecular tritium beta decay. The electrostatic retardation method with magnetic adiabatic collimation (MAC-E filter) combines high energy resolution with high statistics and small background. The various components of the experiment (gaseous tritium source, pumping-transport system, pre- and main spectrometer, detector and rear system) are reviewed.

Glueck, F. [Universitaet Karlsruhe (Thailand), Institut fuer Experimentelle Kernphysik (Germany)]|[Research Institute for Nuclear and Particle Physics, Theory Dep., Budapest (Hungary)

2007-10-12

20

Penning discharge in the KATRIN pre-spectrometer  

NASA Astrophysics Data System (ADS)

The KArlsruhe TRItium Neutrino (KATRIN) experiment is a next-generation, large-scale tritium ?-decay experiment to determine the neutrino mass by investigating the kinematics of tritium ?-decay with a sensitivity of 200 meV/c2 using the MAC-E filter technique. In order to reach this sensitivity a low background level of 10-2 counts per second (cps) is required. A major background concern in MAC-E filters is the presence of Penning traps. A Penning trap is a special configuration of electromagnetic fields that allows the storage of electrically charged particles. This paper describes the mechanism of Penning discharges and the corresponding measurements performed at the test setup of the KATRIN pre-spectrometer. These investigations led to the conclusion that the observed electric breakdown, strong discharges and extremely large background rates were due to discharges caused by Penning traps located at both ends of the pre-spectrometer. Furthermore, the paper describes the design of a new set of electrodes (modified ground electrodes and new ``anti-Penning'' electrodes) to successfully remove these traps. After the installation of these electrodes in the pre-spectrometer, the measurements confirmed that the strong Penning discharges disappeared. The experience gained from the pre-spectrometer was used to design the electrode system of the main spectrometer. Recent measurements with the main spectrometer showed no indications of Penning trap related backgrounds.

Fränkle, F. M.; Glück, F.; Valerius, K.; Bokeloh, K.; Beglarian, A.; Bonn, J.; Bornschein, L.; Drexlin, G.; Habermehl, F.; Leber, M. L.; Osipowicz, A.; Otten, E. W.; Steidl, M.; Thümmler, T.; Weinheimer, C.; Wilkerson, J. F.; Wolf, J.; Zadorozhny, S. V.

2014-07-01

21

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

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

22

Status and commissioning of the Karlsruhe tritium neutrino experiment KATRIN  

NASA Astrophysics Data System (ADS)

Neutrino properties, and especially the determination of the neutrino rest mass, play an important role at the intersections of cosmology, particle physics and astroparticle physics. At present there are two complementary approaches to address this topic in laboratory experiments. The search for neutrinoless double ? decay probes whether neutrinos are Majorana particles and determines an effective neutrino mass value. Experiments based on single ? decay investigate electrons close to their kinematic endpoint in order to determine the neutrino mass by a modelindependent method. The KArlsruhe TRItium Neutrino experiment (KATRIN) is currently the experiment in the most advanced status of commissioning. Applying an ultra-luminous molecular windowless gaseous tritium source and an integrating high-resolution spectrometer of MAC-E filter type, it allows ? spectroscopy close to the tritium endpoint with unprecedented precision and will reach a sensitivity of 200 meV/c2 (90% C.L.) on the neutrino mass.

Thuemmler, Thomas; Katrin Collaboration

2013-10-01

23

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

SciTech Connect

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.

Kizu, K.; Hiratsuka, H.; Miyo, Y.; Ichige, H.; Sasajima, T.; Nishiyama, T.; Masaki, K.; Honda, M.; Miya, N.; Hosogane, N. [Japan Atomic Energy Research Institute (Japan)

2002-09-15

24

Dimensionless Identity Experiments in JT-60U and JET  

Microsoft Academic Search

This paper summarises results of dimensionless identity experiments in JT-60U and JET, aimed at the comparison of the H-mode pedestal and ELM behaviour in the two devices. Given their similar size, dimensionless matched plasmas are also similar in their dimensional parameters (in particular a is the same in JET and JT-60U). Power and density scans were carried out at two

G Saibene; N Oyama; Y Andrew; JG Cordey; C Giroud; K Guenther; T Hatae; GTA Huysmans; Y Kamada; MAH Kempenaars; A Loarte; J Lönnroth; D McDonald; A Meiggs; MFF Nave; V Parail; R Sartori; S Sharapov; J Stober; T Suzuki; M Takechi; K Toi; H Urano

25

Advances in JT-60U facilities and its operation  

Microsoft Academic Search

Recent advances in the JT-60 upgrade (JT-60U) facilities are described which have been made for supporting various physics programs aiming at obtaining reactor-grade plasmas with higher performance in quasi-steady state. It has been proved that B4C-converted (0.3 mm thick) carbon fiber composite (CFC) graphite divertor tiles and decaborane-based boronization using a mixture of deuterium and helium as working gas of

T. Kimura

1995-01-01

26

Word stress correlates in spontaneous child-directed speech in German Katrin Schneider, Bernd Mobius  

E-print Network

Word stress correlates in spontaneous child-directed speech in German Katrin Schneider, Bernd M on the use of acoustic as well as voice quality parameters to mark word stress in German. Our aim was to identify the speech parameters parents use to indicate word stress differences to their children. Therefore

Schneider, Katrin

27

Rotation of Escherichia coli F1-ATPase Hiroyuki Noji,* Katrin Hasler, Wolfgang Junge, Kazuhiko Kinosita, Jr.,*,  

E-print Network

were confirmed by DNA sequencing. Protein preparations. E. coli strain DK8 was transformed with pKH7) for the rotation assay was obtained by expression of the plasmid pKH7 in E. coli strain DK8. pKH7 was constructedRotation of Escherichia coli F1-ATPase Hiroyuki Noji,* Katrin Ha�sler, Wolfgang Junge, Kazuhiko

Junge, Wolfgang

28

Self-majorizing Elements in Archimedean Vector Lattices Katrin Teichert and Martin R. Weber  

E-print Network

Self-majorizing Elements in Archimedean Vector Lattices Katrin Teichert and Martin R. Weber of Analysis Kaiserslautern, Germany Dresden, Germany A finite element in an Archimedean vector lattice N. Such elements exist in many vector lattices and naturally occur in different contexts

Weber, Martin R.

29

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

NASA Technical Reports Server (NTRS)

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.

1974-01-01

30

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

NASA Astrophysics Data System (ADS)

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/c2. 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.

Fränkle, F. M.

2013-08-01

31

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

SciTech Connect

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.

Fränkle, F. M. [F.M. Fränkle Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC (United States)] [F.M. Fränkle Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC (United States)

2013-08-08

32

JT15D simulated flight data evaluation  

NASA Technical Reports Server (NTRS)

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.

Holm, R. G.

1984-01-01

33

JT-60 Upgrade vertical stability experiments and analysis  

NASA Astrophysics Data System (ADS)

The JT-60 Upgrade tokamak (JT-60U), can produce plasmas with vertical elongation (kappa approximately = 1.6), and thus allows investigation of vertical instability phenomena. The present work describes investigation of the vertical stability characteristics of JT-60U plasmas through experimental results and simulation. Experiments described include feedback turnoff cases and high beta(sub p) unstable plasma cases. For purposes of simulation, the plasma is modeled as a rigid assembly of current-carrying axisymmetric loops. A nominal conductor model based on design geometry was modified to reproduce the results of a series of coil excitation experiments using a reduced order system identification approach. A two-coil model was used to fit the experimental coil excitation behavior, and the full order conductor model was modified to allow the dominant modes to reflect the low order dynamic response. The resulting plasma-conductor model is shown to reproduce the vertical stability behavior of JT-60U fairly well. Theoretical predictions of limits on the value of Shafranov (Lambda) achievable in JT-60U are made.

Humphreys, D. A.; Yoshino, Ryuji

1992-05-01

34

The JT-60SA Cryoplant Current Design Status  

NASA Astrophysics Data System (ADS)

In the framework of the ITER Broader Approach, CEA is carrying out the procurement of the Cryogenic System to the JA-EU Satellite Tokamak JT-60SA, which should be operated in Japan at JAEA, Naka in 2014. According to the Conceptual Design Report, JT-60SA is to operate for periods of at least 6 months per year, with major shutdown periods in between for maintenance and further installation upgrades. For this operation scenario, the cryoplant and the cryodistribution have to cope with different heat loads which depend on the different JT-60SA operating states. The cryoplant consists of one 4.5 K refrigerator and one 80 K helium loop, each pre-cooled by LN2. These cryogenic subsystems have to operate simultaneously in order to remove the heat loads from the superconducting magnets, 80 K shields and the divertor cryopumps. The first part of this study is based on the Process Flow Diagram (PFD) and presents the current design status of the JT-60SA cryogenic system. The second part is dedicated to the analysis of the cryoplant normal operation modes including the regeneration mode of the divertor cryopumps. Thanks to this analysis, the architecture of the present PFD is proposed in order to match the technical specifications of the cryoplant with the JT-60SA operation requirements.

Henry, D.; Michel, F.; Roussel, P.; Reynaud, P.; Journeaux, J. Y.; Maréchal, J. L.; Balaguer, D.; Roux, C.; Matsukawa, M.; Yoshida, K.

2008-03-01

35

Electron line shape and transmission function of the KATRIN monitor spectrometer  

SciTech Connect

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 ? 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.

Slezák, M. [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 12116 Prague, Czech Republic and Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Hlavní 130, 25068 ?ež (Czech Republic)

2013-12-30

36

Reduction in cryptosporidiosis associated with introduction of enhanced filtration of drinking water at Loch Katrine, Scotland.  

PubMed

Previous evidence has suggested an association between cryptosporidiosis and consumption of unfiltered drinking water from Loch Katrine in Scotland. Before September 2007, the water was only micro-strained and chlorinated; however, since that time, coagulation and rapid gravity filtration have been installed. In order to determine risk factors associated with cryptosporidiosis, including drinking water, we analysed data on microbiologically confirmed cases of cryptosporidiosis from 2004 to 2010. We identified an association between the incidence of cryptosporidiosis and unfiltered Loch Katrine drinking water supplied to the home (odds ratio 1.86, 95% confidence interval 1.11-3.11, P = 0.019). However, while filtration appears to be associated with initially reduced rates of cryptosporidiosis, evidence suggests it may paradoxically make those consumers more susceptible to other transmission routes in the long-term. These findings support implementation of similar treatment for other unfiltered drinking-water supplies, as a means of reducing cryptosporidiosis associated with drinking water. PMID:23591075

Pollock, K G J; Young, D; Robertson, C; Ahmed, S; Ramsay, C N

2014-01-01

37

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

38

La taxation nergie-climat en Sude Katrin Millock, Ph.D.  

E-print Network

1 La taxation énergie-climat en Suède Katrin Millock, Ph.D. Paris School of Economics, CNRS Centre "Droit de l'environnement, 175 (2010) xx-xx" #12;2 La taxation énergie-climat en Suède 1. Introduction La à l'échec de coordination sur une taxe énergie au niveau européen. Le régime suédois de taxation

Paris-Sud XI, Université de

39

The KATRIN sensitivity to the neutrino mass and to right-handed currents in beta decay  

NASA Astrophysics Data System (ADS)

The aim of the KArlsruhe TRItium Neutrino experiment KATRIN is the determination of the absolute neutrino mass scale down to 0.2 eV, with essentially smaller model dependence than from cosmology and neutrinoless double beta decay. For this purpose, the integral electron energy spectrum is measured close to the endpoint of molecular tritium beta decay. The endpoint, together with the neutrino mass, should be fitted from the KATRIN data as a free parameter. The right-handed couplings change the electron energy spectrum close to the endpoint, therefore they have some effect also to the precise neutrino mass determination. The statistical calculations show that, using the endpoint as a free parameter, the unaccounted right-handed couplings constrained by many beta decay experiments can change the fitted neutrino mass value, relative to the true neutrino mass, by not larger than about 5-10%. Using, incorrectly, the endpoint as a fixed input parameter, the above change of the neutrino mass can be much larger, order of 100%, and for some cases it can happen that for large true neutrino mass value the fitted neutrino mass squared is negative. Publications using fixed endpoint and presenting large right-handed coupling effects to the neutrino mass determination are not relevant for the KATRIN experiment.

Bonn, J.; Eitel, K.; Glück, F.; Sevilla-Sanchez, D.; Titov, N.; Blaum, K.

2011-09-01

40

Stochastic heating by ECR as a novel means of background reduction in the KATRIN spectrometers  

NASA Astrophysics Data System (ADS)

The primary objective of the KATRIN experiment is to probe the absolute neutrino mass scale with a sensitivity of 200 meV (90% C.L.) by precision spectroscopy of tritium ?-decay. To achieve this, a low background of the order of 10-2 cps in the region of the tritium ?-decay endpoint is required. Measurements with an electrostatic retarding spectrometer have revealed that electrons, arising from nuclear decays in the volume of the spectrometer, are stored over long time periods and thereby act as a major source of background exceeding this limit. In this paper we present a novel active background reduction method based on stochastic heating of stored electrons by the well-known process of electron cyclotron resonance (ECR). A successful proof-of-principle of the ECR technique was demonstrated in test measurements at the KATRIN prespectrometer, yielding a large reduction of the background rate. In addition, we have carried out extensive Monte Carlo simulations to reveal the potential of the ECR technique to remove all trapped electrons in a few ms with negligible loss of measurement time in the main spectrometer. This would allow the KATRIN experiment attaining its full physics potential.

Mertens, S.; Beglarian, A.; Bornschein, L.; Drexlin, G.; Fränkle, F. M.; Furse, D.; Glück, F.; Görhardt, S.; Krömer, O.; Leiber, B.; Schlösser, K.; Thümmler, T.; Wandkowsky, N.; Wüstling, S.

2012-08-01

41

Engineering Feature in the Design of JT-60SA  

E-print Network

Engineering Feature in the Design of JT-60SA M. Matsukawa for JA-EU satellite tokamak working group) An optimization of neutron and radiation shielding is made on the vacuum vessel and cryostat structures for the neutron yield of about 2x1019/shot. (8) Existing power supplies, heating & CD system and cooling system

42

----~\\r-~-0~Jt...L. Z~~l~.  

E-print Network

· of trash fish accompanied by addi- "- tional parasites and diseases. These fish limit the growth, C/)I) RESERVOIRS FOR ~1) FISH-RICE FARMING ----~\\r- ~-0~Jt...L. Z~~l~.::d~-~~ ) #12;Fish farming their fields to raise fish when not under production for rice. Unfortunately each type of crop has specific

43

JT8D high pressure compressor performance improvement  

Microsoft Academic Search

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

Gaffin

1981-01-01

44

Application of J-T plants for LP-gas recovery  

SciTech Connect

The paper describes the J-T (Joule-Thomson) process that consists of the adiabatic expansion of a gas through a choke or valve from a high pressure to a low pressure. Various applications of the J-T process in oil and gas production are discussed with emphasis on LPG recovery. It is shown that J-T plants offer an attractive alternative to the turboexpander and refrigeration processes for certain applications.

Crum, F.S.

1981-01-01

45

Electron optical imaging properties of the KATRIN high field solenoid chain  

NASA Astrophysics Data System (ADS)

In this work we study the imaging properties of the KATRIN solenoid chain from the center of the WGTS source to the symmetry point of the main spectrometer entrance solenoid by calculating the trajectories of 200 representative electrons numerically with the simulation package PartOpt. By using both the microscopic approach and the drift equations during the calculation, depending on the magnetic field strength, the calculation times could be reduced to several minutes per trajectory. The image of a cross-type start pattern is produced and it is shown that the maximal energy loss due to synchrotron radiation is less then 0.11 eV.

Osipowicz, Alexander; Zipfel, Bernhard

2014-10-01

46

The materials aspects of the JT-60 device  

NASA Astrophysics Data System (ADS)

JT-60 is the JAERI Tokamak, of which the objective is to achieve the break-even plasma condition making use of a hydrogen plasma. The construction of this device will be completed in the spring of 1985. The following seven items of JT-60 are discussed from the point of view of materials. (1) Vacuum vessel material: Inconel 625, (2) Liner plates as the first wall: Molybdenum and Inconel 625, (3) Fixed limiters, magnetic limiter plates and armor plates for neutral beam injection: Molybdenum, (4) Coating of the first wall: TiC, (5) In-situ coating of TiC within the torus, (6) Non-magnetic structural materials, and (7) Conductor materials for magnet coils.

Hasiguti, R. R.; Tomabechi, K.

1984-05-01

47

Cryogenic requirements for the JT-60SA Tokamak  

NASA Astrophysics Data System (ADS)

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.

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

2012-06-01

48

MIXING STUDY FOR JT-71/72 TANKS  

SciTech Connect

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.

Lee, S.

2013-11-26

49

Results of acoustic testing of the JT8D-109 refan engines  

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

50

JT9D ceramic outer air seal system refinement program  

NASA Technical Reports Server (NTRS)

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.

Gaffin, W. O.

1982-01-01

51

Impact of floods versus routing events on the thermohaline circulation Katrin J. Meissner and Peter U. Clark  

E-print Network

Impact of floods versus routing events on the thermohaline circulation Katrin J. Meissner and Peter events (long term, low amplitude) on the thermohaline circulation and the resulting climate change. We the potential of weakening the thermohaline circulation and therefore causing a cool event in the Northern

Kurapov, Alexander

52

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

NASA Astrophysics Data System (ADS)

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 ? 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.

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

2013-08-01

53

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

NASA Astrophysics Data System (ADS)

The KArlsruhe TRItium Neutrino (KATRIN) experiment will measure the absolute mass scale of neutrinos with a sensitivity of m? = 200 meV/c2 by high-precision spectroscopy close to the tritium ?-decay endpoint at 18.6 keV. Its Windowless Gaseous Tritium Source (WGTS) is a ?-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 ?-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.

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

54

LOCALIZED MHD ACTIVITY NEAR TRANSPORT BARRIERS IN JT-60U AND TFTR  

E-print Network

LOCALIZED MHD ACTIVITY NEAR TRANSPORT BARRIERS IN JT-60U AND TFTR J. Manickam, T. Fujita1, N and Technology, Torrance, CA USA Abstract Localized MHD activity observed in JT-60U and TFTR near transport instability. The appearance of the instability depends on the local pressure gradient, local shear in the q

55

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

SciTech Connect

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.

Leiber, B. [Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany)] [Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); Collaboration: KATRIN Collaboration

2013-08-08

56

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

NASA Astrophysics Data System (ADS)

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(?) 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.

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

2011-01-01

57

High-voltage monitoring with a solenoid retarding spectrometer at the KATRIN experiment  

NASA Astrophysics Data System (ADS)

The KATRIN experiment will measure the absolute mass scale of neutrinos with a sensitivity of m? = 200meV/c2 by means of an electrostatic spectrometer set close to the tritium ?-decay endpoint at 18.6keV. Fluctuations of the energy scale must be under control within ±60mV (±3ppm). Since a precise voltage measurement in the range of tens of kV is on the edge of current technology, a nuclear standard will be deployed additionally. Parallel to the main spectrometer the same retarding potential will be applied to the monitor spectrometer to measure 17.8-keV K-conversion electrons of 83mKr. This article describes the setup of the monitor spectrometer and presents its first measurement results.

Erhard, M.; Bauer, S.; Beglarian, A.; Bergmann, T.; Bonn, J.; Drexlin, G.; Goullon, J.; Groh, S.; Glück, F.; Kleesiek, M.; Haußmann, N.; Höhn, T.; Johnston, K.; Kraus, M.; Reich, J.; Rest, O.; Schlösser, K.; Schupp, M.; Slezák, M.; Thümmler, T.; Vénos, D.; Weinheimer, C.; Wüstling, S.; Zbo?il, M.

2014-06-01

58

Background due to stored electrons following nuclear decays in the KATRIN spectrometers and its impact on the neutrino mass sensitivity  

NASA Astrophysics Data System (ADS)

The KATRIN experiment is designed to measure the absolute neutrino mass scale with a sensitivity of 200 meV at 90% C.L. by high resolution tritium ?-spectroscopy. A low background level of 10-2 counts per second (cps) at the ?-decay endpoint is required in order to achieve the design sensitivity. In this paper we discuss a novel background source arising from magnetically trapped keV electrons in electrostatic retarding spectrometers. The main sources of these electrons are ?-decays of the radon isotopes 219,220Rn as well as ?-decays of tritium in the volume of the spectrometers. We characterize the expected background signal by extensive MC simulations and investigate the impact on the KATRIN neutrino mass sensitivity. From these results we refine design parameters for the spectrometer vacuum system and propose active background reduction methods to meet the stringent design limits for the overall background rate.

Mertens, S.; Drexlin, G.; Fränkle, F. M.; Furse, D.; Glück, F.; Görhardt, S.; Hötzel, M.; Käfer, W.; Leiber, B.; Thümmler, T.; Wandkowsky, N.; Wolf, J.

2013-01-01

59

Effect of a sweeping conductive wire on electrons stored in a Penning-like trap between the KATRIN spectrometers  

NASA Astrophysics Data System (ADS)

The KATRIN experiment is going to search for the mass of the electron antineutrino down to 0.2eV/ c 2. In order to reach this sensitivity the background rate has to be understood and minimised to 0.01 counts per second. One of the background sources is the unavoidable Penning-like trap for electrons due to the combination of the electric and magnetic fields between the pre- and the main spectrometer at KATRIN. In this article we will show that by sweeping a conducting wire periodically through such a particle trap stored particles can be removed, an ongoing discharge in the trap can be stopped, and the count rate measured with a detector looking at the trap is reduced.

Beck, M.; Valerius, K.; Bonn, J.; Essig, K.; Glück, F.; Ortjohann, H.-W.; Ostrick, B.; Otten, E. W.; Thümmler, Th.; Zbo?il, M.; Weinheimer, C.

2010-06-01

60

Design Study of Top Lid with Clamp Structure in JT-60SA Cryostat  

NASA Astrophysics Data System (ADS)

JT-60SA is a fully superconducting coil tokamak upgraded from the JT-60U. This paper focused on the integrity of the top lid of cryostat in JT-60SA. The design requirement for the cryostat in normal operations is to achieve vacuum insulation of 10-3 Pa, and the top flange of the top lid is lightly welded onto its body flange. The weld is tensile-loaded by bending deformation of the top lid due to vacuum pressure of external 0.1 MPa. This weld integrity is evaluated with tensile-load reduction, which results in clamp reinforcement. The structural integrity of the top lid is validated.

Shigetoshi, Nakamura; Yusuke, K. Shibama; Kei, Masaki; Akira, Sakasai

2013-02-01

61

Combined Brayton-JT cycles with refrigerants for natural gas liquefaction  

NASA Astrophysics Data System (ADS)

Thermodynamic cycles for natural gas liquefaction with single-component refrigerants are investigated under a governmental project in Korea, aiming at new processes to meet the requirements on high efficiency, large capacity, and simple equipment. Based upon the optimization theory recently published by the present authors, it is proposed to replace the methane-JT cycle in conventional cascade process with a nitrogen-Brayton cycle. A variety of systems to combine nitrogen-Brayton, ethane-JT and propane-JT cycles are simulated with Aspen HYSYS and quantitatively compared in terms of thermodynamic efficiency, flow rate of refrigerants, and estimated size of heat exchangers. A specific Brayton-JT cycle is suggested with detailed thermodynamic data for further process development. The suggested cycle is expected to be more efficient and simpler than the existing cascade process, while still taking advantage of easy and robust operation with single-component refrigerants.

Chang, Ho-Myung; Park, Jae Hoon; Lee, Sanggyu; Choe, Kun Hyung

2012-06-01

62

JT8D high pressure compressor performance improvement  

SciTech Connect

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% and at least 10/sup 0/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% at typical cruise conditions was calculated based on the sea level test results.

Gaffin, W.O.

1981-11-01

63

JT8D high pressure compressor performance improvement  

NASA Technical Reports Server (NTRS)

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.

Gaffin, W. O.

1981-01-01

64

Advanced tokamak research with integrated modeling in JT-60 Upgradea)  

NASA Astrophysics Data System (ADS)

Researches on advanced tokamak (AT) have progressed with integrated modeling in JT-60 Upgrade [N. Oyama et al., Nucl. Fusion 49, 104007 (2009)]. Based on JT-60U experimental analyses and first principle simulations, new models were developed and integrated into core, rotation, edge/pedestal, and scrape-off-layer (SOL)/divertor codes. The integrated models clarified complex and autonomous features in AT. An integrated core model was implemented to take account of an anomalous radial transport of alpha particles caused by Alfven eigenmodes. It showed the reduction in the fusion gain by the anomalous radial transport and further escape of alpha particles. Integrated rotation model showed mechanisms of rotation driven by the magnetic-field-ripple loss of fast ions and the charge separation due to fast-ion drift. An inward pinch model of high-Z impurity due to the atomic process was developed and indicated that the pinch velocity increases with the toroidal rotation. Integrated edge/pedestal model clarified causes of collisionality dependence of energy loss due to the edge localized mode and the enhancement of energy loss by steepening a core pressure gradient just inside the pedestal top. An ideal magnetohydrodynamics stability code was developed to take account of toroidal rotation and clarified a destabilizing effect of rotation on the pedestal. Integrated SOL/divertor model clarified a mechanism of X-point multifaceted asymmetric radiation from edge. A model of the SOL flow driven by core particle orbits which partially enter the SOL was developed by introducing the ion-orbit-induced flow to fluid equations.

Hayashi, N.; JT-60 Team

2010-05-01

65

Dimensionless pedestal identity experiments in JT-60U and JET in ELMy H-mode plasmas  

Microsoft Academic Search

This paper reports the first results of collaborative experiments in JT-60U and JET to compare ELMy H-mode characteristics in the two machines. The JT-60U\\/JET identity experiments were aimed explicitly at matching edge pedestal parameters in plasmas of the same geometry. The similar size of the two devices allows plasma configurations and conditions to be established for which the match of

G Saibene; T Hatae; D J Campbell; J G Cordey; E de la Luna; C Giroud; K Guenther; Y Kamada; M A H Kempenaars; A Loarte; J Lönnroth; D Mc Donald; M F F Nave; N Oyama; V Parail; R Sartori; J Stober; T Suzuki; M Takechi; K Toi

2004-01-01

66

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

NASA Astrophysics Data System (ADS)

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.

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

2013-10-01

67

J.T. and Margaret Talkington Margaret and J.T. Talkington were well-known as the founders and owners of Margaret's, a  

E-print Network

in 1959 called "Young Ideas" to assist girls transitioning from high school to college. The Talkingtons and J.T. encouraged leadership experiences for young women. Margaret's started a juniors department School for Young Women Leaders, which opened in August 2008. The foundation and Margaret have also

Rock, Chris

68

Oxygen chemisorption compressor study for cryogenic J-T refrigeration  

NASA Technical Reports Server (NTRS)

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.

Jones, Jack A.; Blue, Gary D.

1987-01-01

69

Antimisting kerosene JT3 engine fuel system integration study  

NASA Technical Reports Server (NTRS)

An analytical study and laboratory tests were conducted to assist NASA in determining the safety and mission suitability of the modified fuel system and flight tests for the Full-Scale Transport Controlled Impact Demonstration (CID) program. This twelve-month study reviewed and analyzed both the use of antimisting kerosene (AMK) fuel and the incorporation of a fuel degrader on the operational and performance characteristics of the engines tested. Potential deficiencies and/or failures were identified and approaches to accommodate these deficiencies were recommended to NASA Ames -Dryden Flight Research Facility. The result of flow characterization tests on degraded AMK fuel samples indicated levels of degradation satisfactory for the planned missions of the B-720 aircraft. The operability and performance with the AMK in a ground test engine and in the aircraft engines during the test flights were comparable to those with unmodified Jet A. For the final CID test, the JT-3C-7 engines performed satisfactorily while operating on AMK right up to impact.

Fiorentino, A.

1987-01-01

70

Absolute calibration of microfission chamber in JT-60U  

SciTech Connect

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.

Hayashi, Takao; Nishitani, Takeo; Sukegawa, Atsuhiko M.; Ishikawa, Masao; Shinohara, Kouji [Japan Atomic Energy Agency, Mukouyama 801-1, Naka, Ibaraki 311-0193 (Japan)

2008-10-15

71

Present knowledge about the materials behavior in JT-60  

NASA Astrophysics Data System (ADS)

JT-60 first walls were originally composed of a number of tiles made of either molybdenum or Inconel 625 with 20 ?m thick TiC coating. These first walls, operated after the bakeout at a temperature of 350°C, provided very clean surfaces as well as superior plasma characteristics during Joule heating discharges. Damage of the TiC-coated first walls was modest and localized to specific spots. However, initial results of the additional heating experiments showed degrading effects of locally melted TiC-coated molybdenum and Inconel 625 on the plasma operation. During the venting period from April to May '87 about half of the TiC-coated molybdenum and Inconel 625 was replaced by graphite first walls to prepare for high-power and long-pulse additional heating experiments. After a three-day 300 °c bakeout, 30 h glow discharge cleaning, and 16 h pulsed discharge cleaning at a vessel temperature of around 250°C, a very rapid start-up of the discharge conditioning with plasma current up to 1.0 MA was achieved with 14 shots. Flexibility in plasma operation was increased and the plasma current was increased to 2.9 MA.

Takatsu, H.; Ando, T.; Yamamoto, M.; Arai, T.; Kodama, K.; Ohkubo, M.; Shimizu, M.

1988-07-01

72

Preliminary Studies of the JT-60SA Cryogenic System  

NASA Astrophysics Data System (ADS)

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.

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

2010-04-01

73

The JT9D Jet Engine Diagnostics Program  

NASA Technical Reports Server (NTRS)

The various engine deterioration phenomena that affect JT9D performance retention were studied, and approaches to improve performance retention of engines were identified. The program included surveys of historical data, monitoring of in service engines, ground and flight testing of instrumented engines, analysis, and analytical modeling. Performance deterioration is made up of both short and long term modes, both of which are flight cycle related phenomena. Short term deterioration occurs primarily during airplane acceptance testing prior to delivery to the airline. This effect is caused by flight load and power induced clearance closures and engine deflections with resulting rubbing of airfoils and seals. Long term deterioration is caused by erosion of airfoils and gas path seals during ground operation and take off and by cyclic induced thermal distortion of the high pressure turbine airfoils. Studies of possible remedial approaches have shown that performance retention within 1 to 2 percent of initial revenue service performance can be achieved with a proper program of hot section and cold section maintenance.

Olsson, W. J.

1982-01-01

74

LOW-RESOURCE NOISE-ROBUST FEATURE POST-PROCESSING ON AURORA 2.0 Chia-Ping Chen Jeff Bilmes Katrin Kirchhoff  

E-print Network

LOW-RESOURCE NOISE-ROBUST FEATURE POST-PROCESSING ON AURORA 2.0 Chia-Ping Chen Jeff Bilmes Katrin on the Aurora 2.0 noisy- digits database without requiring any increase in model com- plexity. Compared to the Aurora 2.0 baseline system, our tech- nique improves the average word error rate by 45% in the multi

Washington at Seattle, University of

75

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

Federal Register 2010, 2011, 2012, 2013

...Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines AGENCY: Federal...PW) JT8D-9, -9A, -11, -15, -17, and -17R turbofan engines. This proposed...PW) JT8D-9, -9A, -11, - 15, -17, and -17R turbofan engines. These...

2010-05-19

76

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

NASA Astrophysics Data System (ADS)

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.

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

2010-04-01

77

Pollution reduction technology program for class T4(JT8D) engines  

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

78

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

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

79

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

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

80

VME and network applications for the JT-60U control system  

NASA Astrophysics Data System (ADS)

The control system for the large tokamak JT-60 at JAERI-Naka was completed in 1985. It was originally composed of 16-bit industrial minicomputers and CAMAC systems with 16-bit microcomputers. Rejuvenation of the control system has become necessary to improving the control performance. The renewal of the control system is also stimulated by the requirements for upgrading the software development and hardware maintenance environment of the control system. This paper describes how the control system was and will be upgraded, utilizing the advanced technologies of VME and networks. Two years ago, a VMEbus-based 32-bit multiprocessor system for fast plasma control and a new operator's console using UNIX workstations connected to an Ethernet LAN were developed to cope with upgrading the JT-60 tokamak (JT-60U). VME and network applications are now being extended to the level of subsystem controllers.

Kimura, T.

1994-12-01

81

Influence of External Magnetic Field on AC Losses at EF Coil Joints of JT-60SA  

Microsoft Academic Search

We experimentally and numerically evaluated the AC loss occurred in joints of the EF coil in JT60-SA. There are two kinds of the joints (pancake joint and terminal joint) in the EF coil. Firstly, the AC losses of the joints were experimentally obtained. The experimental results showed that the AC losses in the pancake and the terminal joints were smaller

Tomoaki Takao; Kazuya Nakamura; Toshiyuki Takagi; Naoki Tanoue; Haruyuki Murakami; Kiyoshi Yoshida

2012-01-01

82

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

NASA Technical Reports Server (NTRS)

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.

1975-01-01

83

Plasma Physics found in JT-60 Tokamak over the Last 20 years  

SciTech Connect

This paper summarizes major plasma physics obtained during the period of JT-60 operation for 23 years with special emphasis on research towards steady-state operation of tokamak. Topics included are observation of large bootstrap current fraction, negative shear scenario, demonstration of efficient beam and EC current drive, discovery of current hole, stabilization of the RWM, discovery of ITB (internal transport barrier).

Kikuchi, M. [Japan Atomic Energy Agency, Muko-yama 801-1, Naka city, Ibaraki (Japan)

2009-07-07

84

XML Algebras for Data Mining M. Zhang J.T. Yao  

E-print Network

XML Algebras for Data Mining M. Zhang J.T. Yao Department of Computer Science University of Regina Regina, Saskatchewan, Canada S4S 0A2 E-mail: [zhang2mi, jtyao]@cs.uregina.ca ABSTRACT The XML is a new for data mining due to partially the fact that there is no widely accepted definition of XML mining tasks

Yao, JingTao

85

Stability of the toroidicity-induced Alfven eigenmodes in JT-60U ICRF experiments  

SciTech Connect

It is shown that the stability of toroidicity-induced Alfven eigenmodes (TIE) in JT-60U ICRF experiments is strongly dependent on mode location. This dependence results in sequential excitation of high-n TIE modes as the central safety factor, q, drops in time.

Fu, G.Y.; Cheng, C.Z. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Kimura, H.; Ozeki, T.; Saigusa, M. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

1996-04-01

86

Ion temperature profile simulation of JT-60 plasmas with ion temperature gradient mode transport models  

Microsoft Academic Search

Ion temperature profiles of neutral beam heated plasmas in JT-60 have been simulated by using models of ion thermal diffusivity, chii, based on ion temperature gradient mode (?i mode) turbulence and drift wave turbulence (trapped electron mode and circulating electron mode). Three different chii models proposed by Dominguez and Waltz, Lee and Diamond, and Romanelli are adopted and the predicted

H. Shirai; T. Hirayama; Y. Koide; M. Azumi

1994-01-01

87

244 e) JL Jt MOSQUITO NEWS VOL. 39, No. RECENT DISTRIBUTION RECORDS OF CULEX TARSALIS  

E-print Network

244 e) JL Jt MOSQUITO NEWS VOL. 39, No. RECENT DISTRIBUTION RECORDS OF CULEX TARSALIS IN NEW JERSEY1 WAYNEJ.CRANS Mosquito Research and Control, New Jersey Agricultural Experiment Station, Box 231. New Brunswick, NJ 08903 FREDERICK LESSER THOMAS CANDELETTI Ocean County Mosquito Extermination

88

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

NASA Astrophysics Data System (ADS)

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.

Tzabar, Nir

2014-01-01

89

The H-mode pedestal, ELMs and TF ripple effects in JT-60U\\/JET dimensionless identity experiments  

Microsoft Academic Search

This paper summarizes results of dimensionless identity experiments in JT-60U and JET, aimed at the comparison of the H-mode pedestal and ELM behaviour in the two devices. Given their similar size, dimensionless matched plasmas are also similar in their dimensional parameters (in particular, the plasma minor radius a is the same in JET and JT-60U). Power and density scans were

G. Saibene; N. Oyama; J. Lönnroth; Y. Andrew; E. de la Luna; C. Giroud; G. T. A. Huysmans; Y. Kamada; M. A. H. Kempenaars; A. Loarte; D. McDonald; M. M. F. Nave; A. Meiggs; V. Parail; R. Sartori; S. Sharapov; J. Stober; T. Suzuki; M. Takechi; K. Toi; H. Urano

2007-01-01

90

Critical current measurement of prototype NbTi cable-in-conduit conductor for JT-60SA  

Microsoft Academic Search

The prototype NbTi conductor of JT-60 Super Advanced (JT-60SA) was fabricated and tested to confirm the capability of National Institute for Fusion Science (NIFS) facility for qualification tests of real conductors and to envisage the performance of real conductors. The conductor which length is 3m was formed to racket shape sample without internal joint to minimize the effect of joint.

Kaname Kizu; Katsuhiko Tsuchiya; Tetsuhiro Obana; Kazuya Takahata; Ryo Hoshi; Shinji Hamaguchi; Yoshihiko Nunoya; Kiyoshi Yoshida; Makoto Matsukawa; Nagato Yanagi; Shinsaku Imagawa; Toshiyuki Mito

2009-01-01

91

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

NASA Astrophysics Data System (ADS)

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.

Zhang, Burt; Larson, Melora; Rodriguez, Jose

2010-09-01

92

Finite element-integral acoustic simulation of JT15D turbofan engine  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

93

Development of TiC coated wall materials for JT-60  

NASA Astrophysics Data System (ADS)

Development of titanium carbide (TiC, 20 ?m thick) coated wall materials has been carried out for JT-60. Application of TiC coatings onto molybdenum and Inconel 625 substrates requires a deposition temperature below 950°C and 600°C respectively, because recrystallization of molybdenum and age hardening of Inconel 625 occur above these temperatures. Through this process of coating we developed a new type plasma CVD(TP-CVD method) for molybdenum and a new type PVD(HCD-ARE method) for Inconel 625 which could successfully reduce the deposition temperature to 900°C and 500°C, respectively. The TiC coated wall samples were characterized by AES, ESCA, X-ray diffractometer, EPMA, SEM, metallography, tensile tests, thermal shock tests, and others techniques. As a results of the above measurements, it was demonstrated that the characteristics of those TiC coated walls satisfy the requirements arising from JT-60 operation conditions.

Abe, T.; Murakami, Y.; Obara, K.; Hiroki, S.; Nakamura, K.; Mizoguchi, T.; Doi, A.; Inagawa, K.

1985-08-01

94

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

NASA Technical Reports Server (NTRS)

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.

Gaffin, W. O.

1980-01-01

95

Development of a compact W-shaped pumped divertor in JT-60U  

Microsoft Academic Search

In JT-60U, the modification to a W-shaped pumped divertor will be completed in May 1997, aiming to realize sufficient reduction in heat flux to the targets and good H-mode confinement simultaneously. W-shaped geometry is optimized not only for forming radiative divertor plasmas and reducing the back flow of neutral particles but also for allowing various experimental configurations. Toroidally and poloidally

S. Sakurai; N. Hosogane; K. Masaki; K. Kodama; T. Sasajima; K. Kishiya; S. Takahashi; K. Shimizu; N. Akino; Y. Miyo; H. Hiratsuka; M. Saidoh; M. Inoue; T. Umakoshi; M. Onozuka; M. Morimoto

1998-01-01

96

Overview of JT-60U results towards the establishment of advanced tokamak operation  

Microsoft Academic Search

Recent JT-60U experimental results towards the establishment of advanced tokamak (AT) operation are reviewed. We focused on the further expansion of the operational regime of AT plasmas towards higher betaN regime with wall stabilization. After the installation of ferritic steel tiles in 2005, the high power heating in a large plasma cross-section in which the wall stabilization is expected has

N. Oyama

2009-01-01

97

?>*)3>OOOlt>A -j^t I Ris-R-628(EN)  

E-print Network

in the form of extended abstracts of the Joint Nordic Spring Meeting '92 including the 3rd Nordic Conference?>*«)3>OOOlt>A -j^t D I Risø-R-628(EN) Proceedings oftheJoint Nordic Spring Meeting '92 Edited by Per-Anker Lindgård JOINT NORDIC SPRING MEETING 7-10 MAY 1992 Nyborg Strand, Denmark Risø National

98

Fundamental welding R&D results for manufacturing vacuum vessel of JT-60SA  

Microsoft Academic Search

The real vacuum vessel (VV) manufacturing of JT-60SA has started since November 2009 at Toshiba. Prior to starting manufacturing, fundamental welding R&Ds had been performed by three stages. In the first stage, primary tests for screening welding method were performed. In the second stage, the trial welding for 1m-long straight and curved double shell samples were conducted. The dependences of

Shiro Asano; Toshihisa Okuyama; Toshiwo Oonawa; Yutaka Yanagi; Mitsuru Ejiri; Toshio Kanahara; Koji Ichihashi; Atsushi Kikuchi; Shoichi Mizumaki; Kei Masaki; Yusuke K. Shibama; Masahiro Katayama; Akira Sakasai

2011-01-01

99

Edge Stability in Disappearance of Giant ELMs in JT-60U High Triangularity Discharges  

Microsoft Academic Search

On JT-60U, the appearance of giant ELMs limits the edge pressure gradient (the critical alpha-parameter) of H-mode. The critical alpha-parameter increases with the internal inductance li and close to the high n ideal ballooning mode. The critical alpha-parameter also increases with triangularity footnote Y. Kamada et al., Plasma Phys. Control. Fusion 38 (1996) 1387. Recently, a slow growth of the

T. Oikawa; Y. Kamada; L. L. Lao

1999-01-01

100

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

Federal Register 2010, 2011, 2012, 2013

...Amendment 39-16477; AD 2010-21-17] RIN 2120-AA64 Airworthiness Directives...Whitney JT8D-9, -9A, -11, -15, -17, and -17R Turbofan Engines AGENCY: Federal...PW) JT8D-9, -9A, -11, -15, -17, and -17R turbofan engines. This AD...

2010-10-08

101

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)

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.

1975-01-01

102

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

...Energy Regulatory Commission [Project No. 11392-009] J&T Hydro Company; H. Dean Brooks and W. Bruce Cox; Notice of...Motions To Intervene January 12, 2010. On October 30, 2009, J&T Hydro Company (transferor) and W. Dean Brooks, and H....

2010-01-20

103

Cryogenic performance and numerical modeling of a helium refrigerator for the JT-60SA coil test facility  

NASA Astrophysics Data System (ADS)

In the framework of the JT-60SA project, a cryogenic loop, dedicated to the tests of the JT-60SA Toroidal Field Coils, is planned to be installed at CEA Saclay. To analyze the dynamic thermal behavior of the cryogenic loop and to optimize the cryogenic process control of the coil test facility, dynamic simulations will be carried out with the software EcosimPro. This paper deals with the validation of the software. Experimental power measurements in pure refrigeration on a helium refrigerator have been compared to computations. Results are close and allow validating the software. The modeling of the JT-60SA CTF cryogenic test loop is also described in order to give an overview of the next computations.

Serrand, Alexandre; Abdel-Maksoud, Walid; Genini, Laurent; Juster, François-Paul

2014-01-01

104

High-beta steady-state research with integrated modeling in the JT-60 Upgrade  

SciTech Connect

Improvement of high-beta performance and its long sustainment was obtained with ferritic steel tiles in the JT-60 Upgrade (JT-60U) [T. Fujita et al., Phys. Plasmas 50, 104 (2005)], which were installed inside the vacuum vessel to reduce fast ion loss by decreasing the toroidal field ripple. When a separation between the plasma surface and the wall was small, high-beta plasmas reached the ideal wall stability limit, i.e., the ideal magnetohydrodynamics stability limit with the wall stabilization. A small rotation velocity of 0.3% of the Alfven velocity was found to be effective for suppressing the resistive wall mode. Sustainment of the high normalized beta value of {beta}{sub N}=2.3 has been extended to 28.6 s ({approx}15 times the current diffusion time) by improvement of the confinement and increase in the net heating power. Based on the research in JT-60U experiments and first-principle simulations, integrated models of core, edge-pedestal, and scrape-off-layer (SOL) divertors were developed, and they clarified complex features of reactor-relevant plasmas. The integrated core plasma model indicated that the small amount of electron cyclotron (EC) current density of about half the bootstrap current density could effectively stabilize the neoclassical tearing mode by the localized EC current accurately aligned to the magnetic island center. The integrated edge-pedestal model clarified that the collisionality dependence of energy loss due to the edge-localized mode was caused by the change in the width of the unstable mode and the SOL transport. The integrated SOL-divertor model clarified the effect of the exhaust slot on the pumping efficiency and the cause of enhanced radiation near the X-point multifaceted asymmetric radiation from edge. Success in these consistent analyses using the integrated code indicates that it is an effective means to investigate complex plasmas and to control the integrated performance.

Ozeki, T. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan)

2007-05-15

105

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

NASA Astrophysics Data System (ADS)

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.

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

2004-10-01

106

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

NASA Technical Reports Server (NTRS)

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.

Janus, A. S.

1981-01-01

107

Aerodynamic performance of 0.4066-scale model to JT8D refan stage  

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

108

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

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

109

JT90 Ceramic Outer Air Seal System Refinement Program, Phase 2  

NASA Technical Reports Server (NTRS)

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.

Shiembob, L. T.

1982-01-01

110

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

NASA Technical Reports Server (NTRS)

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.

1975-01-01

111

A filter bank system for scattered spectrum analysis in collective Thomson scattering diagnostic on JT-60  

NASA Astrophysics Data System (ADS)

In JT-60, a collective Thomson scattering (CTS) diagnostic system based on a pulsed CO2 laser (wavelength 10.6 ?m, beam energy 15 J, pulse width 1 ?s) has been developed to measure ion temperature and velocity distribution of fast ions to demonstrate the feasibility of measurements of confined alpha particles. A high power pulsed CO2 laser and heterodyne receiver system using a quantum-well infrared photodetector (QWIP) has been developed and installed in the diagnostic room. In order to resolve frequency distribution of pulsed scattered light (1 ?s), we developed a wideband filter bank system (0.4-4.5 GHz) for scattered spectrum analysis in JT-60 CTS diagnostic. The detector bandwidth and frequency resolution are both determined by the calculation results of expected scattered spectrum. In order to realize wideband multichannel detection, cascade connected seventh order simultaneous-Chebyshev (elliptic) bandpass filters were adopted. Signal to noise ratio based on the noise equivalent power of the QWIP receiver and laser pulse length are also evaluated.

Lee, S.; Kondoh, T.; Yonemoto, Y.; Miura, Y.

2000-12-01

112

Steady-State Operation Scenarios with a Central Current Hole for JT-60SC  

SciTech Connect

A 1.5-dimensional time-dependent transport analysis has been carried out to investigate steady-state operation scenarios with a central current hole by off-axis current drive schemes consistent with a high bootstrap current fraction for the JT-60SC large superconducting tokamak. A steady-state operation scenario with HH{sub y2} = 1.4 and {beta}{sub N} = 3.7 has been obtained at I{sub p} = 1.5 MA, B{sub t} = 2 T, and q{sub 95} = 5, where noninductive currents are developed during the discharge to form a current hole with beam-driven currents by tangential off-axis beams in combination with bootstrap currents by additional on-axis perpendicular beams. The bootstrap fraction increases up to {approx}75% of the plasma current, and the current hole region is enlarged up to {approx}30% of the minor radius at 35 s from the discharge initiation. The current hole is confirmed to be sustained afterward for a long duration of 60 s. The present transport simulation shows that heating equipment designed for JT-60SC is capable of forming and sustaining the current hole only by using off-axis beam-driven currents and bootstrap currents. The stability analysis shows that the beta limit with the conducting wall can be {approx}{beta}{sub N} = 4.5, which is substantially above the no-wall ideal magnetohydrodynamic limit.

Tamai, Hiroshi; Ishida, Shinichi; Kurita, Gen-Ichi; Shirai, Hiroshi; Tsuchiya, Katsuhiko; Sakurai, Shinji; Matsukawa, Makoto; Sakasai, Akira [Japan Atomic Energy Research Institute (Japan)

2004-06-15

113

Improved Confinement in Impurity-Seeded Plasmas in JT-60U and TFTR  

NASA Astrophysics Data System (ADS)

Improved energy confinement in impurity-seeded plasmas has been observed on several tokamaks, offering the possibility of high confinement at high density and reduced power to the wall. We analyze and compare impurity-seeded plasmas in TFTR and JT-60U, with a goal of understanding the improved confinement. In JT-60U ELMy H-modes with Ar puffing at n_e^GW = 0.7, H = 1.4 has been achieved, about 40% higher than with D2 puffing alone. In TFTR supershots at NBI power Pb ~ 16 MW, \\chii and \\chi_? decreased with Kr and Xe puffing; the ITG mode was stabilized by Kr puffing. At high power (Pb > 28 MW) with Kr injection, confinement and fusion power were improved, and carbon blooms were eliminated. Analysis includes thermal transport by the TRANSP and TOPICS codes, microinstability predictions by FULL and GS2, E× B shearing rate by TRV, and impurity transport and radiated power distributions by MIST and IMPACT.

Hill, K. W.; Ernst, D. R.; Park, H. K.; Rewoldt, G.; Synakowski, E. J.; Taylor, G.; Bush, C. E.; Asakura, N.; Kubo, H.; Sakurai, S.; Itami, K.; Tamai, H.; Konoshima, S.; Higashijima, S.; Shimizu, K.; Shirai, H.; JT-60u Team

2000-10-01

114

Pedestal Characteristics of H-Mode Plasmas in JT-60U and ASDEX Upgrade  

NASA Astrophysics Data System (ADS)

The role of the pedestal structure in ELMy H-mode plasmas for the core energy confinement and for the ELM energy losses were investigated in two tokamak-type devices, JT-60U and ASDEX Upgrade. The confinement degradation seen at higher densities is attributed to the reduction of the pedestal temperature limited by the ELM activities and the stiffness of the temperature profiles. In high triangularity or impurity seeded H-modes, in which higher energy confinement is generally achieved, a higher pedestal temperature is obtained by improving the edge MHD stability or the density profile peaking, respectively. The upper bound of the ELM energy loss is characterized by the pedestal energy. The ELM energy loss can become smaller at fixed pedestal energy when the pedestal collisionality is raised. Raising the pedestal collisionality also enhances the inter-ELM perpendicular transport loss and reduces the ELM loss power fraction. In ASDEX Upgrade, the continuous pellet injection is shown to effectively mitigate ELM losses while preserving the core confinement quality. In JT-60U, the operation regime of grassy ELM is investigated and shown to achieve highly integrated performance of high energy confinement with small ELMs in the low collisionality regime.

Urano, Hajime; Kamada, Yutaka; Takizuka, Tomonori; Suttrop, Wolfgang; Horton, Lorne; Lang, Peter; Kubo, Hirotaka; Oyama, Naoyuki; Takenaga, Hidenobu; Asakura, Nobuyuki

115

Transient Heat Transport in Subcooled He II Associated with JT Effect  

SciTech Connect

Transient heat transport in subcooled He II has been investigated in a 1 m long rectangular channel with distributed contractions: one-closed end has a heater, while the other end is open to the He II bath. Experiments were conducted applying heat pulses and recording the temperature profile with seven Allan Bradley resistors placed along the channel. Cernox sensor was indium soldered on the heater surface to monitor the onset of film boiling. As the onset of heat pulse, the pressure at the heater surface increased because of phase change from subcooled He II to He I. Further increasing of heat pulse leads to coexistence of triple-phase, He I vapor layer, He I and subcooled He II, at the vicinity of heater surface. These effects induced instantaneous He II temperature drop along the channel, which is caused by Joule-Thomson (JT) effect. A simple model gives an approximate mechanism of pressure increase in the channel. The paper describes transient heat transport mechanism in the channel and discusses JT effect within the channel.

Maekawa, R.; Iwamoto, A.; Hamaguchi, S. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

2004-06-23

116

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

Federal Register 2010, 2011, 2012, 2013

...removing certain high-pressure compressor (HPC) shafts before their certified life limits...was prompted by reports of cracks in five HPC shafts. We are proposing this AD to correct...five JT9D-7R4H1 engines containing an HPC shaft with cracks in the thread...

2011-07-13

117

Ion temperature profile simulation of JT-60 and TFTR plasmas with ion temperature gradient mode transport models  

Microsoft Academic Search

Ion temperature profiles of neutral beam heated plasmas in JT-60 and TFTR have been simulated using models of ion thermal diffusivity, chii, based on ion temperature gradient mode (etai mode) turbulence and drift wave turbulence (trapped electron mode and circulating electron mode). The ion temperature profiles measured by charge exchange recombination spectroscopy are compared to predicted Ti profiles calculated from

H. Shirai; T. Hirayama; Y. Koide; H. Yoshida; O. Naito; M. Sato; T. Fukuda; T. Sugie; M. Azumi; D. R. Mikkelsen; S. D. Scott; B. Grek; K. W. Hill; D. W. Johnson; D. K. Mansfield; H. K. Park; B. C. Stratton; E. J. Synakowski; G. Taylor; H. H. Towner

1994-01-01

118

Hydrogen isotopes retention in the outboard first wall tiles of JT-60U  

NASA Astrophysics Data System (ADS)

We have investigated hydrogen isotopes retention in graphite tiles used as outboard first wall armors of JT-60U by means of SEM, TDS and SIMS. The SEM examination confirmed that these tiles are mostly eroded. Different from graphite divertor tiles, in which H retention was dominant owing to isotopic replacement during HH discharges preformed after DD discharges to remove tritium, deuterium is dominated in hydrogen isotopes retention of the outboard first wall tiles showing deeper penetration. This is attributed to the injection of high energy D and less isotopic replacement due to the lower temperature of the outboard first wall tiles. This type of hydrogen retention could not be avoided for the metallic wall. Although the amount of hydrogen isotopes retained per unit area in the outboard first wall tiles was much less than that for the divertor tiles, the integrated retention over the whole first wall surface could be very large.

Yoshida, M.; Tanabe, T.; Nobuta, Y.; Hayashi, T.; Masaki, K.; Sato, M.

2009-06-01

119

Particle control study towards burning plasma control in JT-60U  

NASA Astrophysics Data System (ADS)

Study of particle control, such as control of fuel and impurity densities and plasma responses to fuelling and pumping, has been conducted in JT-60U to expand understanding of burning plasma controllability. Peakedness of density profiles increased with decreasing collisionality, which is consistent with ITG/TEM turbulence transport theory. Other control parameters, such as toroidal rotation, existed, i.e. density peaking with counter rotation. Metal impurity accumulation was observed with peaked density profiles, while light impurity accumulation was not observed. Confinement degraded with supersonic molecular beam injections (SMBI), while it was unchanged with high-field-side shallow pellet injection, indicating flexible control using combined fuelling. 2-D divertor simulations suggested that dynamic plasma-wall interaction slows plasma response to divertor pumping. By using the burning plasma simulation scheme, responses of burning plasmas to fuelling were investigated. It was demonstrated to reduce the simulated fusion gain with SMBI due to confinement degradation and flattening of pressure profile.

Takenaga, H.; JT-60 Team

2009-06-01

120

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

NASA Technical Reports Server (NTRS)

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.

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

1974-01-01

121

The effect of wall materials on hydrogen recycling in JT-60  

NASA Astrophysics Data System (ADS)

A model calculation on hydrogen recycling at the wall in JT-60 has been made for three different wall materials (molybdenum, Inconel 625 and titanium carbide) for the case when the plasma is heated by neutral beam injection. It has been assumed that only charge exchange neutrals hit the wall. Values of the recycling coefficient required to keep constant plasma densities for two different flux densities 1 × 10 16 and 3 × 10 16 H/cm 2·s onto the wall have been estimated to be 0.75 and 0.92, respectively. By assuming Maxwellian energy distributions (200 and 400 eV), the recycling coefficients have been calculated as a function of time and wall temperature by taking account of particle re-emission due to backscattering, diffusion and saturation overflow. The wall temperature regions which satisfy the above criteria for 5 and 10 s discharges have been discussed for the three materials.

Sone, K.; Murakami, Y.

1984-05-01

122

An overview of recent erosion/deposition and hydrogen retention studies in JT-60U  

NASA Astrophysics Data System (ADS)

Recent erosion/deposition and hydrogen retention studies in JT-60U have been summarized. Inner divertor tiles were covered by thick redeposited layers, whereas outer divertor tiles eroded, and significant carbon deposition was observed at the outer exhaust slot, i.e. the bottom side of the outer dome wing. The outboard first wall tiles were mostly eroded. The mass balance of carbon erosion and redeposition in the whole vessel is still missing. H+D retention in the redeposited layers on inner divertor tiles correlates well with their thickness, and hydrogen concentration in the layers, (H+D)/C, was uniformly ~0.03 except for a few ?m top surface layers with ~0.05. Surface D within a few ?m in depth was mostly replaced by H owing to H-H (H plasma +H neutral beam injection (NBI)) discharges made for tritium removal, indicating possible T removal by D-D discharges. Rather high D retention was observed on the outer dome wing probably owing to higher energy deuteron implantation originating from NBI. JT-60U seems a good example to reduce carbon deposition as well as tritium retention. Well-aligned tiles with more or less no steps between neighboring tiles in the toroidal and poloidal directions could reduce net erosion and redeposition not only on the plasma-facing surface but also at the plasma-shadowed area. During plasma discharges, the surface temperature in the divertor area becomes higher than the base temperature (600 K), which could reduce tritium retention significantly.

Tanabe, T.; Masaki, K.; Sugiyama, K.; Yoshida, M.

2009-12-01

123

Mobilization of Escherichia coli R1 silver-resistance plasmid pJT1 by Tn5Mob into Escherichia coli C600  

Microsoft Academic Search

Summary Escherichia coli Rl is an Ag+-resistant strain that, as we have shown recently, harbours at least two large plasmids, pJT1 (83 kb) and pJT2 (77 kb). Tn5-Mob was introduced into theE. coli Rl host replicon via conjugation on membrane filters. The transfer functions of plasmid RP4-4 were provided in this process and Tn5-Mob clones mated withE. coli C600 yielded

Mary-Ellen Starodub; Jack T. Trevors

1990-01-01

124

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

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

125

Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60U  

Microsoft Academic Search

Neutral beam injection (NBI) used for JT-60U is required to generate negative ions of 500 keV energies. To produce such high-energy ions, three-stage electrostatic accelerators consisting of three insulator rings made of fiberglass reinforced plastic (FRP) are applied. The surface discharges along FRP insulators are one of the most serious problems in the development of NBI. To increase the hold-off

Y. Yamano; M. Takahashi; S. Kobayashi; M. Hanada; Y. Ikeda

2008-01-01

126

Introduction of a Saturated Bath in Vincenta Models: Application to the Cryogenic System for JT-60SA Tokamak  

NASA Astrophysics Data System (ADS)

The CEA is involved in large helium refrigeration applied to the future experimental fusion reactors (e.g. ITER or JT-60SA). Pulsed operation of such machines results in heat load variations which the refrigerators have to cope with. One solution to smooth pulsed loads is to use a large thermal buffer, and in the case of JT-60SA cryogenic system, a saturated thermal bath is one of the investigated solutions. A 1D thermo hydraulic model describing the cooling loop associated with TF (Toroidal Field) coils and TF casing has been developed using Vincenta code to calculate the heat load arriving to the buffer (saturated bath). However, the liquid helium buffer itself and its coupling with the primary loop was not modelized. This paper shows results obtained using the existing functionalities in Vincenta code to model a saturated bath. For very large bath volumes, bath temperature remains almost steady and the power removed is equal to those previously calculated. On the other side, for smaller buffer volumes (e.g. JT-60SA scheme), it has been found that the increase of temperature fluctuations does not vary proportionally with the decrease of the buffer volume.

Rousset, B.; Roussel, P.; Michel, F.; Hitz, D.

2010-04-01

127

Transition from accelerated to decelerated regimes in JT and CGHS cosmologies  

NASA Astrophysics Data System (ADS)

In this work we discuss the possibility of positive-acceleration regimes, and their transition to decelerated regimes, in two-dimensional (2D) cosmological models. We use general relativity and the thermodynamics in a 2D space-time, where the gas is seen as the sources of the gravitational field. An early-Universe model is analyzed where the state equation of van der Waals is used, replacing the usual barotropic equation. We show that this substitution permits the simulation of a period of inflation, followed by a negative-acceleration era. The dynamical behavior of the system follows from the solution of the Jackiw-Teitelboim equations (JT equations) and the energy-momentum conservation laws. In a second stage we focus the Callan-Giddings-Harvey-Strominger model (CGHS model); here the transition from the inflationary period to the decelerated period is also present between the solutions, although this result depends strongly on the initial conditions used for the dilaton field. The temporal evolution of the cosmic-scale function, its acceleration, the energy density and the hydrostatic pressure are the physical quantities obtained through the analysis.

Christmann, M. H.; Devecchi, F. P.; Kremer, G. M.; Zanetti, C. M.

2004-09-01

128

Removal of the deposition on JT-60 tile by nano-sec pulsed-laser irradiation  

NASA Astrophysics Data System (ADS)

To clarify the property of tritium removal from carbon codeposition by using pulsed-laser induced desorption, hydrogen removal from co-deposits on JT-60 divertor tile using a fourth-harmonic emission (266 nm) of a nano-sec Nd:YAG laser was demonstrated. The threshold laser fluence for ablation was ˜0.3 J/cm 2, which was slightly higher compared to that of the pico-sec laser irradiation. The energy absorption coefficient for the nano-sec laser, which was obtained by fitting the removal rate by so-called Beer's law, was larger than the pico-sec laser. Since the time constant of thermal wave propagation into the target is of the order of nano-sec, such differences between nano- and pico-sec lasers could be attributed to thermal effects. The ablation threshold of the deposited layer was lower than that of a pure graphite, which could be attributed to the difference of thermal conductivity between deposited layer and pure graphite. The removal rate of the nano-sec laser was higher than that of pico-sec laser in the fluence range of >˜0.5 J/cm 2. On the other hand, the production ratio [hydrocarbon species]/[H 2] continuously increased with the laser fluence, and no significant ionization of carbon was observed in this fluence range. This indicated that the fluence range in this study was "weak"-ablation range, which was still not sufficient to minimize the hydrocarbon production.

Sugiyama, K.; Sakawa, Y.; Tanabe, T.; Watanabe, D.; Shibahara, T.; Masaki, K.

2010-10-01

129

Edge Stability in Disappearance of Giant ELMs in JT-60U High Triangularity Discharges  

NASA Astrophysics Data System (ADS)

On JT-60U, the appearance of giant ELMs limits the edge pressure gradient (the critical ?-parameter) of H-mode. The critical ?-parameter increases with the internal inductance li and close to the high n ideal ballooning mode. The critical ?-parameter also increases with triangularity footnote Y. Kamada et al., Plasma Phys. Control. Fusion 38 (1996) 1387. Recently, a slow growth of the pedestal structure in the giant-ELMy phase was observed in a long pulse high ?p ELMy H-mode discharges with high triangularity (? ~0.45-0.5). The pedestal width and the pedestal ion temperature increase gradually with a long time constant ~2 sec. Simultaneously, ?p increases and li decreases. At a low q_95 ~3.5, giant ELM activity survives throughout the NB heating phase. On the other hand, at high q_95 ~5-6, amplitude of the giant ELM gradually decreases and finally it disappears. Then the pedestal width and the pedestal temperature increase further, and li decreases simultaneously. The access to the second stability regime to high-n ballooning mode is one of the possible explanations. The stability analyses with the detailed edge treatment in equilibirum reconstruction and the relation with the evolution of the edge bootstrap current are presented.

Oikawa, T.; Kamada, Y.; Lao, L. L.

1999-11-01

130

JT150 1/2-scale nozzle jet noise experiment and comparison with prediction  

NASA Technical Reports Server (NTRS)

As part of a program to study flight effects on the exhaust noise of a full scale JT15D engine, static half scale model jet noise experiments were conducted. Acoustic data were recorded for microphone angles of 45 deg to 155 deg with jet conditions for the model scale nozzle corresponding closely to those at 55, 73 and 97 percent of corrected rated speed for the full scale engine. These data are useful for determining the relative importance of jet and core noise in the static full scale engine test data and will in turn allow for a proper evaluation of flight effects on the exhaust noise results. The model scale data are also compared with the coaxial jet noise prediction. Above 1000 Hz, the prediction is nominally 0 to 3 dB higher than the data. The arithmetic mean of the differences between the experimental OASPL and the predicted OASPL for all angles for each run ranged from 0 to -3.2 dB. The standard deviation of all the OASPL differences is 2.2 dB. The discrepancies are greatest at low primary jet velocities and appear to be due to inadequacy in the variable jet density exponent incorporated in the prediction procedure.

Groesbeck, D. E.; Wasserbauer, C. A.

1983-01-01

131

Titanium carbide coating on inconel 625 liner for JT-60 BY HCD-ARE  

NASA Astrophysics Data System (ADS)

The HCD-ARE (activated reactive evaporation using a hollow cathode discharge) method was applied to coat the TiC layer, being a low Z material, on the full-size Inconel 625 liner for JT-60 with the aim of ascertaining its capability of mass-productive coating and further of supplying suitable products which satisfy the properties required from fusion devices. The film was deposited at the substrate temperature of 500°C using an in-line evaporation system consisting of four vacuum chambers. The characteristics of the films are nearly equal to each other over the whole area of the sample liner. The deposited films of about 20 ?m thick and a nearly stoichiometric composition show a preferred orientation in the (220) direction and the value of their line half-width is 0.23 0.26 deg. The lattice constants are nearly equal to those of the bulk crystal. By XPS observation the chemical shifts in C1s and Ti 2p{sol3}/{2} binding of the TiC film were about -3 and +1 eV which are nearly equal to those of the single crystal, respectively. As a result of convenient valuation of the durability of coatings, TiC film exhibiting a strong adhesion and an adequate durability was obtained by the HCD-ARE method.

Inagawa, K.; Watanabe, K.; Tanaka, I.; Itoh, A.; Abe, T.; Murakami, Y.; Mizoguchi, T.; Itou, Y.

1984-12-01

132

Study of current decay time during disruption in JT-60U tokamak  

NASA Astrophysics Data System (ADS)

An L/R model that predicts the current decay time from the circuit equation is essentially used for the design of the International Thermonuclear Experimental Reactor. In order to verify the validity of the L/R model in the determination of current decay time during disruption, the plasma current decay time in the JT-60U tokamak is studied using experimental plasma resistance and inductance. The plasma resistance during the initial phase of current quench is estimated from the electron temperature profile measured using the electron cyclotron emission diagnostic system and by measuring the He I line emission intensity ratios and plasma inductance is estimated by the Cauchy-Condition surface method using magnetic sensor signals. Further, the radiation-induced disruptive plasma discharges with massive neon gas puffing are also analysed. The observed area-normalized current decay times have a weak dependence on the electron temperature, particularly in a small decay time region (5-10 ms m-2). The observed decay times are lesser by one order of magnitude than the decay times estimated by the L/R model. However, a novel model for decay time prediction, which takes into account the time derivative of the plasma inductance, wields results that are extremely consistent with the experimental decay time.

Shibata, Y.; Watanabe, K. Y.; Okamoto, M.; Ohno, N.; Isayama, A.; Kurihara, K.; Nakano, T.; Oyama, N.; Kawano, Y.; Matsunaga, G.; Sakakibara, S.; Sugihara, M.; Kamada, Y.; JT-60 Team

2010-02-01

133

Pressure transfer function of a JT15D nozzle due to acoustic and convected entropy fluctuations  

NASA Technical Reports Server (NTRS)

An acoustic transmission matrix analysis of sound propagation in a variable area duct with and without flow is extended to include convected entropy fluctuations. The boundary conditions used in the analysis are a transfer function relating entropy and pressure at the nozzle inlet and the nozzle exit impedance. The nozzle pressure transfer function calculated is compared with JT15D turbofan engine nozzle data. The one dimensional theory for sound propagation in a variable area nozzle with flow but without convected entropy is good at the low engine speeds where the nozzle exit Mach number is low (M=0.2) and the duct exit impedance model is good. The effect of convected entropy appears to be so negligible that it is obscured by the inaccuracy of the nozzle exit impedance model, the lack of information on the magnitude of the convected entropy and its phase relationship with the pressure, and the scatter in the data. An improved duct exit impedance model is required at the higher engine speeds where the nozzle exit Mach number is high (M=0.56) and at low frequencies (below 120 Hz).

Miles, J. H.

1982-01-01

134

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

NASA Technical Reports Server (NTRS)

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.

Olsson, W. J.

1982-01-01

135

Investigation of performance deterioration of the CF6/JT9D high bypass ratio turbofan engines  

NASA Technical Reports Server (NTRS)

The extent and magnitude of performance deterioration of the Pratt and Whitney JT9D, and the General Electric CF6 engine models is presented. Overall engine and contributing module performance deterioration with respect to flight cycles and/or time are analyzed. The overall engine performance deterioration analyses are based on data obtained from historical records, special engine tests, and tests for specific effects. Hardware inspection data from overhaul shops and special module tests are the basis for the modular performance deterioration data used in the analyses. Various damage mechanisms such as seal rubs, erosion, surface roughness and thermal distortion, and how they contribute to performance deterioration are included in the modular analyses. Results indicate that early performance deterioration occurring within the first few flights of these engines is less than 1 percent in cruise specific fuel consumption (SFC), that it is event oriented, and that it is the result of increased blade tip clearances. This performance deterioration gradually increases to about 2.5 to 3.0 percent (including the initial short term deterioration) after 2500 to 3000 flights where increased blade tip clearances, airfoil quality degradation, and thermal distortion are the contributing causes.

Ziemianski, J. A.

1981-01-01

136

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

PubMed

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

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

2010-02-01

137

Disappearance of giant ELMs and appearance of minute grassy ELMs in JT-60U high-triangularity discharges  

Microsoft Academic Search

In JT-60U H-mode plasmas, giant (type I) ELMs disappear and minute grassy ELMs appear when triangularity delta, edge safety factor q95 and betap are high enough. Complete suppression of giant ELMs was observed at delta≳0.45, q95≳6 and betap≳1.6. At higher delta (0.54), giant ELMs can disappear at a lower q95 (~4.0). In the grassy ELMy H-mode, edge temperature and pressure

Y. Kamada; T. Oikawa; L. Lao; T. Takizuka; T. Hatae; A. Isayama; J. Manickam; M. Okabayashi; T. Fukuda; K. Tsuchiya

2000-01-01

138

Characteristics and control of the type I edge localized mode in JT-60U  

NASA Astrophysics Data System (ADS)

The detailed characteristics of the precursor of the type I edge localized mode (ELM) have been studied in JT-60U using diagnostics with high temporal and spatial resolution such as a microwave reflectometer, electron cyclotron emission (ECE) heterodyne radiometer and grating polychromator. Coherent density and temperature precursors have been observed before the collapse phase of type I ELM. The growth rate of the precursor is evaluated to be ?/?A ~ 10-3 for several edge pedestal conditions. From the phase delay between ECE signals measured at two toroidal locations and the frequency of the precursor, the toroidal mode number is experimentally evaluated as n = 8-10 or 14-16 assuming that the precursor rotates toroidally with the same toroidal rotation speed of carbon impurity. It is found that the dominant n varies with each ELM under the same plasma condition. The ratio of the pressure gradient inside the pedestal (?pin) to the pressure gradient within the pedestal (?pped) has been confirmed as an important parameter in determining the ELM energy loss (?WELM) normalized to the pedestal stored energy (Wped), ?WELM/Wped. From the comparison of the reduction rate in the ion temperature profile due to ELMs, a larger reduction rate within the pedestal and a wider ELM affected area are observed in the plasma with larger ?pin/?pped. When the plasma near the top of the pedestal on the high-field side is heated by an electron cyclotron wave (ECW) power of 1.57 MW, the ?WELM/Wped is reduced by ~35%, together with an increase in the ELM frequency. The increasing rate of the ELM frequency with the heating power is about four times larger in the ECW injection case than the natural power dependence observed in the neutral beam injection case.

Oyama, N.; Hayashi, N.; Aiba, N.; Isayama, A.; Urano, H.; Sakamoto, Y.; Kamada, Y.; Takizuka, T.; JT-60 Team

2011-03-01

139

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

SciTech Connect

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.

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. [Japan Atomic Energy Research Institute (Japan)

2002-09-15

140

Fast collimated neutron flux measurement using stilbene scintillator and flashy analog-to-digital converter in JT-60U  

NASA Astrophysics Data System (ADS)

A line-integrated neutron emission profile is routinely measured using the radial neutron collimator system in JT-60U tokamak. Stilbene neuron detectors (SNDs), which combine a stilbene organic crystal scintillation detector (SD) with an analog neutron-gamma pulse shape discrimination (PSD) circuit, have been used to measure collimated neutron flux. Although the SND has many advantages as a neutron detector, the maximum count rate is limited up to ˜1×105counts/s due to the analog PSD circuit. To overcome this issue, a digital signal processing system (DSPS) using a flash analog-to-digital converter (Acqiris DC252, 8GHz, 10bits) has been developed at Cyclotron and Radioisotope Center in Tohoku University. In this system anode signals from photomultiplier of the SD are directory stored and digitized. Then, the PSD between neutrons and gamma rays is performed using software. The DSPS has been installed in the vertical neutron collimator system in JT-60U and applied to deuterium experiments. It is confirmed that the PSD is sufficiently performed and collimated neutron flux is successfully measured with count rate up to ˜5×105counts/s without the effect of pileup of detected pulses. The performance of the DSPS as a neutron detector, which supersedes the SND, is demonstrated.

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

2006-10-01

141

Heat treatment of CuCrZr cooling tubes for JT-60SA monoblock-type divertor targets  

NASA Astrophysics Data System (ADS)

The JT-60SA divertor has to withstand a maximum heat flux of ˜15 MW/m 2 for 100 s, and JAEA has developed the monoblock-type CFC divertor target for JT-60SA. To boost production yield of the targets, CFC cracking due to thermal expansion and contraction of the CuCrZr cooling tubes must be suppressed. CuCrZr properties depend strongly on the heat treatment, and the target is heat-treated during the manufacturing processes of brazing, solution treatment, and annealing. CuCrZr test specimens were heat-treated with the targets, and the strength and hardness of the specimens were almost the same for the quenching cooling rates of ˜0.65 °C/s and ˜1.5 °C/s around 800 °C. This indicates that the slower quenching cooling rate is acceptable, and consequently at least half of the mock-ups could remove the required high heat flux of 15 MW/m 2.

Higashijima, S.; Sakurai, S.; Sakasai, A.

2011-10-01

142

INTEGRATION OF SQUID l/f NOISE AND ITS APPLICATION TO A SUPERCONDUCTING GYROSCOPE J.T. Anderson and B. Cabrera  

E-print Network

INTEGRATION OF SQUID l/f NOISE AND ITS APPLICATION TO A SUPERCONDUCTING GYROSCOPE J.T. Anderson Abstract.- SQUID noise in the 1/f noise region was integrated for 140 hours in a narrow frequency band. INTRODUCTION.- SQUID magnetometers exhibit increa- sing noise power at low frequencies /l/ which tends to rise

Paris-Sud XI, Université de

143

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

NASA Technical Reports Server (NTRS)

Two inflow control devices, (ICD's) one in-duct and the other external to the duct, were tested on a JT15D engine to determine their ability to remove inflow turbulence without altering the sound transmission to the far field. The objective of the program was to develop means of accurately simulating flight fan noise on ground static test stands. The results generally indicated that both the in-duct 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 in-duct ICD caused attenuation under most conditions.

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

1979-01-01

144

Comparison of several inflow control devices for flight simulation of fan tone noise using a JT15D-1 engine  

NASA Technical Reports Server (NTRS)

To enable accurate simulation of in-flight fan tone noise during ground static tests, four devices intended to reduce inflow disturbances and turbulence were tested with a JT15D-1 turbofan engine. These inflow control devices (ICD's) consisted of honeycomb/screen structures mounted over the engine inlet. The ICD's ranged from 1.6 to 4 fan diameters in size, and differed in shape and fabrication method. All the ICD's significantly reduced the BPF tone in the far-field directivity patterns, but the smallest ICD's apparently introduced propagating modes which could be recognized by additional lobes in the speeds; at supersonic fan tip speed the smallest ICD's had some measurable loss, but the largest had no loss. Data from a typical transducer show that the unsteady inflow distortion modes (turbulence) were eliminated or significantly reduced when either of the ICD's was installed. However, some steady inflow distortion modes remained.

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

1980-01-01

145

Properties of hydrogen desorption from co-deposits on JT-60 graphite tile by pulsed-laser ablation  

NASA Astrophysics Data System (ADS)

For the purpose of tritium removal from carbon co-deposits on plasma-facing material of fusion device, pulsed-laser induced desorption of hydrogen from co-deposits on JT-60 open-divertor tile has been investigated. The fundamental (1064 nm) and fourth harmonic (266 nm) emission of a 20 ps-Nd: YAG laser were used, and dependences of hydrogen desorption on laser intensity IL and wavelength ? were studied. Hydrogen-desorption efficiency, defined as the ratio between the number of desorbed hydrogen by laser irradiation and that of hydrogen retained in the ablated volume, was largest in the region, where strong ionization of C + occurred, and was larger for ? = 266 nm, in which a laser photon can cut C-H bond, compared with that for ? = 1064 nm. For the ablative removal of hydrogen, a short-wavelength and high-power laser is desirable.

Watanabe, D.; Sakawa, Y.; Shibahara, T.; Sugiyama, K.; Shoji, T.; Yamazaki, K.; Tanabe, T.

2007-06-01

146

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

NASA Astrophysics Data System (ADS)

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.

Gupta, Prabhat Kumar; Rabehl, Roger

2014-07-01

147

Long pulse production of high current D{sup -} ion beams in the JT-60 negative ion source  

SciTech Connect

The first long pulse production of high power D{sup -} ion beams has been demonstrated in the JT-60 U negative ion sources, each of which was designed to produce 22 A, 500 keV D{sup -} ion beams. Voltage holding capability and the grid power loading were examined for long pulse production of high power D{sup -} ion beams. From the correlation between voltage holding and the light intensity of cathodoluminescence from the Fiber Reinforced Plastic insulators, the acceleration voltage for stable voltage holding capability was found to be less than 320-340 kV where the light was sufficiently suppressed. By tuning the extraction voltage, the grid power loadings in the ion sources were decreased to the allowable levels for long pulse injection without a significant reduction of the beam power. After tuning the acceleration and extraction voltages, D{sup -} ion beams of 12.5 and 9.8 A were produced at 340 keV with cesium seeding at a rate of {approx}14 {mu}g/s into the ion sources. The pulse duration of these D{sup -} ion beams was extended step by step, and then was successfully extended up to 18 s without degradation of the negative ion production. The D{sup -} ion beams were neutralized to yield 3.6 MW D{sup 0} beams by a gas cell, and then injected into the JT-60 U plasma. Further, a slight reduction of D{sup -} ion beam power allowed the longer injection duration of 21 s at a D{sup 0} beam power of 3.2 MW. The success in the long pulse production of a high power D{sup -} ion beam shows that negative ion beams can be produced during a few tens of seconds without degradations of negative ion production and the voltage holding in a large Cs-seeded negative ion source.

Hanada, M.; Kamada, M.; Akino, N.; Ebisawa, N.; Honda, A.; Kawai, M.; Kazawa, M.; Kikuchi, K.; Komata, M.; Mogaki, K.; Noto, K.; Ohshima, K.; Takenouchi, T.; Tanai, Y.; Usui, K.; Yamazaki, H.; Ikeda, Y.; Grisham, L. R. [Japan Atomic Energy Agency, 801-1 Mukohyama-Naka, Ibaraki 310-0193 (Japan); Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States)

2008-02-15

148

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

NASA Astrophysics Data System (ADS)

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, ?h0, 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 ?B?/B < 10-3 at the plasma boundary. As ?h0 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.

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

2013-07-01

149

Dependence of edge stability on plasma shape and local pressure gradients in the DIII-D and JT-60U tokamaks  

Microsoft Academic Search

The dependence of edge stability on plasma shape and local pressure gradients P' in the DIII-D and JT-60U tokamaks is studied. The stronger plasma shaping in DIII-D allows the edge region of DIII-D discharges with type I (giant) ELMs to have access to the second region of stability for ideal ballooning modes and a larger edge pedestal pressure gradient P'

L. L. Lao; Y. Kamada; T. Oikawa; Larry R Baylor; K. H. Burrell; V. S. Chan; M. S. Chance; M. S. Chu; J. R. Ferron; T. Fukuda; T. Hatae; A. Isayama; G. J. Jackson; A. W. Leonard; M. A. Makowski; J. Manickam; M. Murakami; M. Okabayashi; T. H. Osborne; P. B. Snyder; E. J. Strait; S. Takeji; T. Takizuka; T. S. Taylor; A. D. Turnbull; K. Tsuchiya; M. R. Wade

2001-01-01

150

Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60U.  

PubMed

Neutral beam injection (NBI) used for JT-60U is required to generate negative ions of 500 keV energies. To produce such high-energy ions, three-stage electrostatic accelerators consisting of three insulator rings made of fiberglass reinforced plastic (FRP) are applied. The surface discharges along FRP insulators are one of the most serious problems in the development of NBI. To increase the hold-off voltage against surface flashover events, it is necessary to investigate the FRP insulator properties related to surface discharges in vacuum. This paper describes surface flashover characteristics for FRP and alumina samples under vacuum condition. The results show that the fold-off voltages for FRP samples are inferior to those of alumina ceramics. In addition, measurement results of surface resistivity and volume resistivity under vacuum and atmospheric conditions, secondary electron emission characteristics, and cathodoluminescence under some keV electron beam irradiation are also reported. These are important parameters to analyze surface discharge of insulators in vacuum. PMID:18315145

Yamano, Y; Takahashi, M; Kobayashi, S; Hanada, M; Ikeda, Y

2008-02-01

151

Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60U  

SciTech Connect

Neutral beam injection (NBI) used for JT-60U is required to generate negative ions of 500 keV energies. To produce such high-energy ions, three-stage electrostatic accelerators consisting of three insulator rings made of fiberglass reinforced plastic (FRP) are applied. The surface discharges along FRP insulators are one of the most serious problems in the development of NBI. To increase the hold-off voltage against surface flashover events, it is necessary to investigate the FRP insulator properties related to surface discharges in vacuum. This paper describes surface flashover characteristics for FRP and alumina samples under vacuum condition. The results show that the fold-off voltages for FRP samples are inferior to those of alumina ceramics. In addition, measurement results of surface resistivity and volume resistivity under vacuum and atmospheric conditions, secondary electron emission characteristics, and cathodoluminescence under some keV electron beam irradiation are also reported. These are important parameters to analyze surface discharge of insulators in vacuum.

Yamano, Y.; Takahashi, M.; Kobayashi, S.; Hanada, M.; Ikeda, Y. [School of Science and Engineering, Saitama University (Japan); Japan Atomic Energy Agency (Japan)

2008-02-15

152

Zeeman polarimetry measurement for edge current density determination using Li-beam probe on JT-60U  

NASA Astrophysics Data System (ADS)

Zeeman polarimetry system using Li-beam probe has been developed for the edge current density measurement in the JT-60U tokamak, which measures the polarization angle ? (related to the pitch angle of the magnetic field) by means of photoelastic modulators, etalons, and phase sensitive detection using digital lock-in amplifiers with the accuracy in the ? of ?? ˜0.1°. The diagnostic has 20-channel viewing chords covering the plasma peripheral region of normalized minor radius r /a˜0.8-1 with a spatial resolution of up to ˜1 cm. Li-beam injection with beam current of up to ˜5 mA has been achieved. A new tuning method of the wavelength for the etalon has been demonstrated, scanning the beam acceleration voltage and keeping a beam current constant during a single shot. The peak wavelength of the etalon is adjusted in the direction to both blue- and redshifts by changing the angle of incidence and increasing the temperature, respectively. Time evolution of the edge current density profile has been determined for the current ramp experiment in the Ohmically heated discharges. In addition, the edge current density profile with the local peak of jped˜0.15-0.25 MA/m2 at r /a˜0.9 has been identified in the H-mode plasma, which is correlated with large pressure gradient in the pedestal region.

Kamiya, K.; Fujita, T.; Kojima, A.; Kubo, H.

2010-03-01

153

Dynamics of low-n shear Alfvén modes driven by energetic N-NB ions in JT-60U  

NASA Astrophysics Data System (ADS)

Dynamics of fast ions and shear Alfvén waves are simulated using MEGA, a global nonlinear hybrid code. The scenario considered is based on JT-60U shot E039672, driven by strong negative-ion-based neutral beams (N-NB), just before the onset of a so-called abrupt large event (ALE). It is found that modes with toroidal mode numbers n = 2, 3, 4 can be destabilized, besides the n = 1 mode studied previously. The properties of the modes with n > 1 are sensitive to the value of the plasma beta and the form of the fast ion distribution, so simulation conditions are set up as realistically as presently possible. When the fast ion drive exceeds a certain threshold, the n = 3 mode is enhanced through a convective amplification process while following fast ions were displaced either by the n = 3 mode itself or by the n = 1 mode. The fast ion transport in several cases, simulated with single- or multiple-n modes, is analysed and implications of the results for the explanation of ALEs are discussed.

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

2014-10-01

154

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

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

155

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

NASA Astrophysics Data System (ADS)

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.

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

2013-09-01

156

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

NASA Technical Reports Server (NTRS)

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.

Joynes, D.; Balut, J. P.

1974-01-01

157

Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60Ua)  

NASA Astrophysics Data System (ADS)

Neutral beam injection (NBI) used for JT-60U is required to generate negative ions of 500keV energies. To produce such high-energy ions, three-stage electrostatic accelerators consisting of three insulator rings made of fiberglass reinforced plastic (FRP) are applied. The surface discharges along FRP insulators are one of the most serious problems in the development of NBI. To increase the hold-off voltage against surface flashover events, it is necessary to investigate the FRP insulator properties related to surface discharges in vacuum. This paper describes surface flashover characteristics for FRP and alumina samples under vacuum condition. The results show that the fold-off voltages for FRP samples are inferior to those of alumina ceramics. In addition, measurement results of surface resistivity and volume resistivity under vacuum and atmospheric conditions, secondary electron emission characteristics, and cathodoluminescence under some keV electron beam irradiation are also reported. These are important parameters to analyze surface discharge of insulators in vacuum.

Yamano, Y.; Takahashi, M.; Kobayashi, S.; Hanada, M.; Ikeda, Y.

2008-02-01

158

Balance of ionization and recombination of carbon ions in high density peripheral plasmas of the JT-60 U tokamak  

SciTech Connect

In high density and low temperature peripheral plasmas of JT-60 U, i.e. detached divertor plasmas, C III and C IV lines were observed by a visible and VUV spectrometers in order to investigate dominant radiators, radiation power and particle balance between the radiators. An emission peak was found between the inner strike and the X-point. With increasing electron density, the emission peak moved to the X-point with a constant electron temperature of {approx}7 eV. In the case the emission peak was located on the X-point, the dominant radiators in the emission peak were C{sup 2+} and C{sup 3+}, which contributed 30% and 60% to the total radiative power. It was found that C{sup 3+} was produced by the ionization of C{sup 2+} and the volume recombination of C{sup 4+} at a similar rates. However, the loss flux of C{sup 3+} was lower by two orders of magnitude than the C{sup 3+} production flux, indicating that another loss mechanism such as transport loss around the X-point was significant.

Nakano, T.; Kubo, H.; Asakura, N.; Shimizu, K. [Japan Atomic Energy Agency, 801-1, Mukoyama, Naka, Ibaraki, 311-0193 (Japan)

2009-05-02

159

Overview of JT-60U results for the development of a steady-state advanced tokamak scenario  

NASA Astrophysics Data System (ADS)

Recent JT-60U experimental results towards the development of a steady-state advanced tokamak scenario are presented. The JT-60U experiments within the past two years emphasize the extension of the operation regimes and the development of active control for high bootstrap current fraction plasmas with a strong linkage between pressure and current profiles. Reduction of a toroidal magnetic field ripple by installing ferritic steel tiles decreases the fast ion loss and consequently enables one to access the new regimes due to an increase in net heating power. The decrease in the fast ion loss also contributes to access to the new regimes through confinement improvement attributed to the reduction of counter toroidal rotation. High ?N (~4.2) exceeding the no-wall ideal limit is achieved at li = 0.8-1 in the high ?p ELMy H-mode plasmas with a weak positive shear at the large volume configuration close to the wall. The large volume configuration had so far suffered from the large toroidal field ripple. The value of ?N reaches the ideal wall limit, where RWM is suppressed by the plasma rotation. Small critical rotation velocity about 0.3% of Alfvén velocity is found for suppressing RWM. High ?N · HH98(y,2) of 2.2 with ?N ~ 2.3 and HH98(y,2) ~ 1 is sustained for 23.1 s, significantly longer than the current diffusion time (~12?R) in the high ?p ELMy H-mode plasmas. This duration is extended to a time scale for enhancement of recycling owing to a decrease in the wall-pumping rate. Successful recycling and density control is demonstrated for ~30 s in the enhanced recycling regime even with outgas from the wall by maximizing the divertor pumping rate in the high-density ELMy H-mode plasmas. With small effects of the toroidal field ripple reduction, the controllability is investigated in the reversed shear (RS) plasmas with a high bootstrap current fraction (fBS) of ~0.7-1. It is difficult to sustain these plasmas using a feedback control scheme for global parameter such as stored energy and the duration is determined by the ideal limit or slow ITB degradation in the linkage of current and pressure profiles. Real time qmin control is demonstrated with MSE diagnostic and LHCD at fBS = 0.46 with the strong pressure and current profile linkage. Physics studies also progress towards burning plasma control. Semi-global change of the ITB structure is observed in both high ?p mode and RS plasmas. Complete NTM suppression is demonstrated with misalignment of ECCD position less than about half of the island width. Fast ELM propagation to the main chamber wall is observed, and significant hydrogen retention in the main chamber wall is found. In the plasma-shadowed area underneath the divertor region, the averaged carbon deposition rate is significantly low, however the (H + D)/C retention rate is high (~0.8).

Takenaga, H.; JT-60 Team

2007-10-01

160

Quasisteady High-Confinement Reversed Shear Plasma with Large Bootstrap Current Fraction under Full Noninductive Current Drive Condition in JT-60U  

SciTech Connect

A quasisteady reversed shear plasma with a large bootstrap current fraction ({approx}80% ) has been obtained for the first time in the JT-60U tokamak. The shrinkage of reversed shear region was suppressed by the bootstrap current peaked at the internal transport barrier (ITB) layer and the ITBs at a large radius were sustained, which, by combination with an H -mode edge pedestal, resulted in a high confinement or 2.2times the H -mode scaling for 6times energy confinement time or 2.7s. Furthermore, a full noninductive current drive was obtained by the bootstrap current and the beam driven current.

Fujita, T.; Ide, S.; Kamada, Y.; Suzuki, T.; Oikawa, T.; Takeji, S.; Sakamoto, Y.; Koide, Y.; Isayama, A.; Hatae, T. (and others)

2001-08-20

161

Local Heating and Current Drive using the Fundamental O-mode EC wave on JT-60U  

NASA Astrophysics Data System (ADS)

In JT-60U, a 3 MW-level ECRF system using 3 gyrotrons was completed in March 2000. The frequency of 110 GHz was selected to launch a fundamental O-mode from the low field side. The toroidal injection angle is fixed about 15^circ to drive plasma current and poloidal injection angle can be steered using a mirror for deposition control. Up to now, the power of ~1.5 MW × 3 second ( ~2.2 MW at gyrotrons) was successfully injected to study the local electron heating and current drive. The mode purity can be controlled by rotatable grooved mirrors that generate adequate elliptical polarization. The correlation between the O-mode purity and the increase of electron temperature was clearly obtained at n_e0>0.8×10^19m-3, while weak dependence of electron heating on mode purity was observed at low density ( ~0.3 ×10^19m-3) due to the Doppler effect of fundamental X-mode absorption with toroidal oblique angle. A strongly peaked Te profile with T_e0>10 keV at n_e0 ~1×10^19m-3 was obtained for 1 s with the injected power of ~1.5MW when the O-mode purity is adjusted more than 80%. Impact on sawtooth activity, both suppression and enhancement depending on ECW deposition and direction of EC driven current to the plasma current, was observed. In view of local current drive, changes in MSE signals were observed.

Kajiwara, Ken; Isayama, Akihiko; Suzuki, Takahiro; Ide, Shunsuke; Kasugai, Atsusi; Takahashi, Koji; Ikeda, Yoshitaka; Fujii, Tsuneyuki

2000-10-01

162

Compatibility of advanced tokamak plasma with high density and high radiation loss operation in JT-60U  

NASA Astrophysics Data System (ADS)

Compatibility of advanced tokamak plasmas with high density and high radiation loss has been investigated in both reversed shear (RS) plasmas and high ?p H-mode plasmas with a weak positive shear on JT-60U. In the RS plasmas, the operating regime is extended to high density above the Greenwald density (nGW) with high confinement (HHy2 > 1) and high radiation loss fraction (frad > 0.9) by tailoring the internal transport barriers (ITBs). With a small plasma-wall gap, the radiation loss in the main plasma (inside the magnetic separatrix) reaches 80% of the heating power due to metal impurity accumulation. However, high confinement of HHy2 = 1.2 is sustained even with such a large radiation loss in the main plasma. By neon seeding, the divertor radiation loss is enhanced from 20% to 40% of the total radiation loss. In the high ?p H-mode plasmas, high confinement (HHy2 = 0.96) is maintained at high density ( \\bar{n}_{\\rme}/n_GW=0.92 ) with high radiation loss fraction (frad ~ 1) by utilizing high-field-side pellets and argon (Ar) injection. The high \\bar{n}_{\\rme}/n_GW is attributed to the formation of strong density ITB. Strong core-edge parameter linkage for confinement improvement is observed, where the pedestal pressure and the core plasma confinement increase together. The measured radiation profile including contributions from all impurities in the main plasma is peaked, and the central radiation is ascribed to the contribution from Ar accumulated inside the ITB. Impurity transport analyses indicate that the Ar density profile, twice as peaked as the electron density profile, which is the same level as that observed in the high ?p H-mode plasma, can yield an acceptable radiation profile even with a peaked density profile in a fusion reactor.

Takenaga, H.; Asakura, N.; Kubo, H.; Higashijima, S.; Konoshima, S.; Nakano, T.; Oyama, N.; Porter, G. D.; Rognlien, T. D.; Rensink, M. E.; Ide, S.; Fujita, T.; Takizuka, T.; Kamada, Y.; Miura, Y.; JT-60 Team

2005-12-01

163

Development of an extended thermo-hydraulic simulation tool for fusion magnet design study - Application to the initial versions of JT-60SA TF coils layout  

NASA Astrophysics Data System (ADS)

In the framework of the EU participation to JT-60SA project [1], a dedicated simulation tool named after Thermo-hydraulic EXtended Tool (TEXTO) was developed at CEA between 2006 and 2007 in order to address in a reliable way the calculation of the magnet conductor temperature increase and temperature margins in different operating conditions. The simulation process is based on three different codes, addressing each specific aspects (MCNP for the 3D nuclear heat calculation, TRAPS for magnetic field, ANSYS for 2D transverse thermal contribution of coil casing), which finally stand as input for the well established code GANDALF (with transient helium properties). Both steady-state operating and disruption transient regimes can be studied with this process and a first application is performed on the basis of the design and operating conditions available at this time on JT-60SA TF magnets, i.e. the first version of the different design stages. The complete analysis is shown together with the associated proposals for the TF conductor layout that could be derived from these studies.

Nicollet, S.; Lacroix, B.; Zani, L.; Hertout, P.; Portafaix, Ch.; Villari, R.

2010-01-01

164

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

165

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

NASA Astrophysics Data System (ADS)

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, V?) 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.

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

2013-08-01

166

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

PubMed

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

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

167

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

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.

Kawakami, S.; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan)] [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Shibata, Y.; Isayama, A.; Kawano, Y. [Japan Atomic Energy Agency, Naka 311-0193 (Japan)] [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Watanabe, K. Y. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan) [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); National Institute for Fusion Science, Toki 509-5292 (Japan); Takizuka, T. [Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan)] [Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Okamoto, M. [Ishikawa National College of Technology, Ishikawa 929-0392 (Japan)] [Ishikawa National College of Technology, Ishikawa 929-0392 (Japan)

2013-11-15

168

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)

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.

1973-01-01

169

Molecular cloning, expression and properties of an alpha/beta-Galactoside alpha2,3-sialyltransferase from Vibrio sp. JT-FAJ-16.  

PubMed

We cloned, expressed and characterized a novel alpha/beta-galactoside alpha2,3-sialyltransferase from Vibrio sp. bacterium JT-FAJ-16. Using a alpha2,3-sialyltransferase gene from a marine bacterium as a probe, a DNA sequence encoding a 402-amino-acid protein was identified from the JT-FAJ-16 genomic library. The protein showed 27.3-64.7% identity to the bacterial sialyltransferases classified into glycosyltransferase family 80. The protein showed sialyltransferase activity when expressed in Escherichia coli. The N-terminal truncated form of the enzyme was amplified in E. coli and its recovered activity was 215.7 unit/l culture medium. It was purified as a single band on SDS-PAGE through the three chromatographic steps. The specific activity of the purified recombinant enzyme reached 57.5 unit/mg protein. The alpha2,3sialylation was confirmed by (1)H- and (13)C-NMR analyses of the reaction products. The enzyme was optimally active at pH 5.5 and at 20 degrees C. Interestingly, the enzyme used both the alpha- and beta-anomers of galactosides as acceptors, suggesting that it can be described as an alpha/beta-galactoside alpha2,3-sialyltransferase. The enzyme had a wide range of acceptor substrate specificities. It transferred N-acetylneuraminic acid (NeuAc) to various monosaccharides and various oligosaccharides, and both N-linked and O-linked asialo-glycoprotein. These results suggest that the enzyme can be used as a powerful tool for the study for glycotechnology. PMID:17673486

Takakura, Yoshimitsu; Tsukamoto, Hiroshi; Yamamoto, Takeshi

2007-09-01

170

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)

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.

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

1983-01-01

171

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)

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.

1975-01-01

172

Measurement of sputtering yields of CD_4,C_2D2 and C_2D4 at the carbon divertor plate of JT-60U  

NASA Astrophysics Data System (ADS)

Under cold and dense divertor conditions, the chemical erosion process reduces the lifetime of carbon divertor tiles in fusion reactors. It is important to evaluate the chemical sputtering yield at the divertor exposed to the high particle flux in large tokamaks such as JT-60U. Spectral bands of CD and C2 have been measured in order to evaluate the chemical sputtering yields of CD4 ,C_2D2 and C_2D4 in L-mode discharges. From the intensities of the spectral bands, the yields of CD4 and C_2D_2+C_2D4 are estimated to be about 1-2% in an ion flux range of 0.2-2×10^23m-2/s. The yields of CD4 and C_2D_2+C_2D4 in this work are about half compared with laboratory data(R.Yamada J.Nucl.Mater. 145-147(1987)359) in a low ion flux range ( ~2×10^19m-2/s). However, the ratio of CD4 to C_2D_2+C_2D4 is almost the same in both experiments. The number of carbon atoms originating from C_2D2 and C_2D4 is comparable to or larger than that from CD_4. Therefore, heavy hydrocarbons as well as CD4 have the contribution to carbon impurity generation in a wide range of the ion flux. This work is the first quantitative estimation of the sputtering yields of C_2D2 and C_2D4 in tokamaks.

Nakano, T.; Kubo, H.; Higashijima, S.; Sugie, T.; Asakura, N.; Itami, K.

2000-10-01

173

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

SciTech Connect

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.

Suzuki, T.; Isayama, A.; Ide, S.; Fujita, T.; Oikawa, T.; Sakata, S.; Sueoka, M.; Hosoyama, H.; Seki, M. [Japan Atomic Energy Research Institute, Naka Fusion Research Establishment (Japan)

2005-09-26

174

Exhaust emissions characteristics and variability for Pratt and Whitney JT8D-7A gas turbine engines subjected to major overhaul and repair. Final report Nov 1978-Feb 1979  

SciTech Connect

Seven Pratt and Whitney Aircraft (PWA) JT8D-7A turbofan engines were tested at Kennedy International Airport, New York, to evaluate exhaust emissions characteristics and data variability after overhaul. The measured data show that the engines tested did not meet the Environmental Protection Agency (EPA) emission standards. A comparison of the measured data, obtained from the seven overhauled engines evaluated under this program, with new engine data obtained from PWA show that there is a great deal of similarity between the two sets of data. Differences shown in this report between new engine and overhauled engine data are due to the quantity of the engines sampled; the new engine data represent a larger sample size. Satisfactory data can be measured by using the test procedures, instrumentation, and equipment defined in this report.

Becker, E.E.; Frings, G.; Cavage, W.C.

1980-09-01

175

The results of a low-speed wind tunnel test to investigate the effects of the Refan JT8D engine target thrust reverser on the stability and control characteristics of the Boeing 727-200 airplane  

NASA Technical Reports Server (NTRS)

The effects of the Refan JT8D side engine target thrust reverser on the stability and control characteristics of the Boeing 727-200 airplane were investigated using the Boeing-Vertol 20 x 20 ft Low-Speed Wind Tunnel. A powered model of the 727-200 was tested in groud effect in the landing configuration. The Refan target reverser configuration was evaluated relative to the basic production 727 airplane with its clamshell-deflector door thrust reverser design. The Refan configuration had slightly improved directional control characteristics relative to the basic airplane. Clocking the Refan thrust reversers 20 degrees outboard to direct the reverser flow away from the vertical tail, had little effect on directional control. However, clocking them 20 degrees inboard resulted in a complete loss of rudder effectiveness for speeds greater than 90 knots. Variations in Refan reverser lip/fence geometry had a minor effect on directional control.

Kupcis, E. A.

1974-01-01

176

JT90 thermal barrier coated vanes  

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

177

Gruppe 1 12:45 13:30 Franz Katrin  

E-print Network

Kaiser Ulla Stefanie Julia Müller Matthias Angela Sebastian Thomas Stefan Nina Katharina Schwarzmann Ivlev Daniela Kipfstuhl Lauke Lehmann Mackrodt Denise Merkel Laura Peukert Reitter Ryborz Schenk Schlirf 14:25 ­ 15:10 Nicole Kathrin Dick Angela Simon Friedrich Melanie Sebastian Paul Hubmann Klein Andreas

Keller, Gerhard

178

J. theor. Biol. (1998) 195, 1326 Article No. jt980749  

E-print Network

Academic Press Solving the Complementarity Dilemma: Evolving Strategies for Simultaneous Hermaphroditism of major types of sexual reproduction, particularly simultaneous hermaphroditism. We find with simultaneous hermaphroditism can predominate only when a substantial cost of repeatedly adopting the female

Sargent, Robert Craig

179

Sorption J-T refrigeration utilizing manganese nitride chemisorption  

NASA Technical Reports Server (NTRS)

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.

Jones, Jack; Lund, Alan

1990-01-01

180

J. theor. Biol. (1998) 193, 485495 Article No. jt980717  

E-print Network

, Ecole Normale Superieure, 7 quai St. Bernard, Bax t. A, 7e` me e´ tage, CC237, 75252 Paris Cedex 05 of the dynamics of host­parasite­hyperparasite systems. Our aim is to compare the dynamics of these systems

Hochberg, Michael

181

J. theor. Biol. (1998) 194, 429455 Article No. jt980796  

E-print Network

about without the necessity for changes in gene frequencies. Demographic implications include transitions, and the weak or even negative correlation in economically developed societies between control

Grafen, Alan

182

J. theor. Biol. (1998) 193, 345358 Article No. jt980706  

E-print Network

, such as the proportions of species at each of the trophic levels, and the lengths of food chains. There have also been) We introduce the Webworld model, which links together the ecological modelling of food web structure resources from the external environment through the food web to each of the species, and to determine mean

Caldarelli, Guido

183

Copyright Notice Triton Burnup Study in JT-60U  

E-print Network

the midplane of the vessel, just outside the toroidal field coil position as shown in Fig.1. The scintillating emission is dominant because the neutron monitor is designed to has almost same detection efficiency

184

The Assessment Continuum James (J.T.) Laverty  

E-print Network

borrowed from: Gerd Kortemeyer Before, in, and after lecture #12;What makes a good use of technology for technology sake · not scattered "technology highlights" - consistently applied - students know what to expect on task - make the students interact with the materials - do not waste student time · Giving effective

185

Clean-up of graphite first walls in JT-60  

NASA Astrophysics Data System (ADS)

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.

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

1989-04-01

186

J. theor. Biol. (1998) 194, 461483 Article No. jt980766  

E-print Network

. In the case of flagellated bacteria such as E. coli, movement consists of a series of more-or-less straight-ranging amoeba to a multicellular fruiting body in Dd involves many of the basic processes, including chemotaxis

Weinberger, Hans

187

JSIS Course Numbers: Sorted by Old 3/31/2012 No. Old Title Jt Dept1 Jt Dept2  

E-print Network

RELIGIONS JSIS B 207 COMPARING RELIGIONS RELIG 205 RELIG/VIOLENC/PEACE HUM 205 NEAR E 205 JSIS B 205 RELIG/VIOLENC/PEACE RELIG 210 INTRO JUDAISM JSIS B 145 INTRO JUDAISM RELIG 211 ISLAM NEAR E 211 JSIS B 211 ISLAM RELIG 212

Hochberg, Michael

188

JSIS Course Numbers: Sorted by Joint Dept 3/31/2012 No. New Title Jt Dept1 Jt Dept2  

E-print Network

&POL VIOLENCE JSIS B 526 POLITICAL ISLAM ANTH 526 SIS 526 POLITICAL ISLAM JSIS A 531 SOCL MOVEMENT INDIA ANTH RELG/IDEN/CLTR PLRL ANTH 330 RELIG 330 RELG/IDEN/CLTR PLRL JSIS A 341 POL VIOLENCE S ASIA ANTH 341 SISA 341 POL VIOLENCE S ASIA JSIS B 356 BUDDHISM & SOCIETY ANTH 352 RELIG 350 BUDDHISM & SOCIETY JSIS A 370

Borenstein, Elhanan

189

SHALMANESER A Toolchain For Shallow Semantic Parsing Katrin Erk and Sebastian Pad  

E-print Network

role. The same development is currently gaining mo- mentum in the area of predicate-argument structure-argument structure, whose attractiveness lies in its intermediate position between syntax and "deep" seman- tics butter was passed quickly by Fred" would receive the same representation as in Fig. 1), and to some

Padó, Sebastian

190

A review of "Donne's Augustine: Renaissance Cultures of Interpretation" by Katrin Ettenhuber  

E-print Network

?s sermon of 24 May 1629,? Ettenhuber suggests, ?were the dissolution of parliament two months earlier, on 10 March, and the controversial peace with France in April of the same year? (185). For Ettenhuber, these political contexts allow readers to bet...?s sermon of 24 May 1629,? Ettenhuber suggests, ?were the dissolution of parliament two months earlier, on 10 March, and the controversial peace with France in April of the same year? (185). For Ettenhuber, these political contexts allow readers to bet...

Harris, Mitchell M.

2012-01-01

191

Automatic Learning of Language Model Structure Kevin Duh and Katrin Kirchhoff  

E-print Network

words, such as morphological or syntactic features. However, the number of possible choices for model for languages with rich morphology. Such languages typically ex- hibit a large number of word types in relation to word tokens in a given text, which leads to high perplexity and a large number of un- seen word

Washington at Seattle, University of

192

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

PubMed

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

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

2013-01-01

193

Feasibility of photoelectron sources for testing the energy scale stablity of the KATRIN beta-ray spectrometer  

E-print Network

Photoabsorption of nuclear gamma-rays in thin metallic convertors was examined with the aim to produce monoenergetic photoelectrons of kinetic energy around 18.6 keV and natural width of about 1 eV. Calculations were carried out for commercial photon sources of 241Am (1.1 GBq) and 119mSn (0.5 GBq) irradiating Co and Ti convertors. Photoelectrons ejected by 241Am gamma- and X-rays from Co convertors of various thickness were measured with two electrostatic spectrometers.

Dragoun, O; Kaspar, J; Bonn, J; Kovalik, A; Otten, E W; Venos, D; Weinheimer, Ch

2010-01-01

194

Back to the Basics using Developing Technologies JT Land and Cattle LLC  

E-print Network

"exceptional drought" prevailed? Ranch NDVI shows 75-84% of "Normal" #12;Does it work?? Mar-May Index 147.5 #12" or " Biomass?" #12;#12;Does it work?? Mar-May Index 147.5 #12;Dept. of Rangeland Security: #12;Ranch NDVI shows;#12;#12;WEB BASED DROUGHT MANAGEMENT? 2006 GLCI Conference St. Louis, MO #12;#12;(Ability to add or move

195

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

Federal Register 2010, 2011, 2012, 2013

...customized versions, 770407 and 770408). All HPC Stage 5-15 Disks and 72-35-00 Inspection-03...72-31-00 Check-00. All HPC Stage 5-15 Disks and 72-35-00 Check-00...72-31-00 Inspection-03. All HPC Stage 5-15 Disks and 72-35-00...

2011-11-22

196

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

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

197

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

NASA Technical Reports Server (NTRS)

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.

Stromberg, W. J.

1981-01-01

198

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

SciTech Connect

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.

Makowski, K. P.; Hayashil, B. [Alliance Spacesystems, LLC, Pasadena, CA 91103 (United States); Larson, M. E.; Loc, A. S.; Zhang, B. X.; Leland, R. S. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

2010-04-09

199

Studies on Structural Analysis Related to the Design of the JT-60 Vacuum Vessel.  

National Technical Information Service (NTIS)

Studies on structural analysis of a vacuum vessel of tokamak-type fusion devices are presented. The present studies are proposals for the structural analysis procedures of the tokamak-type fusion devices and are composed of five parts, each of which cover...

H. Takatsu

1987-01-01

200

Microseismic mapping of a Cotton Valley hydraulic fracture using decimated downhole arrays J.T. Rutledge  

E-print Network

Microseismic mapping of a Cotton Valley hydraulic fracture using decimated downhole arrays J three hydraulic fracture operations in the Cotton Valley gas field of East Texas. Two 48-level, 3 a consortia of operators and service companies conducted an extensive hydraulic fracture imaging demonstration

201

Activation measurements of the neutron yield at the JT-60U Tokamak.  

National Technical Information Service (NTIS)

This paper describes activation measurements of the neutrons from fusion plasmas. We are primarily interested in two narrow bands of neutron energies around 2.5 and 14 MeV. The d-d reaction has two branches with nearly equal probability, one generating a ...

T. Carlsson, M. Carlsson

1994-01-01

202

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

NASA Technical Reports Server (NTRS)

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.

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

1978-01-01

203

LOCALIZED MHD ACTIVITY NEAR TRANSPORT BARRIERS IN JT60U AND TFTR  

E-print Network

LOCALIZED MHD ACTIVITY NEAR TRANSPORT BARRIERS IN JT­60U AND TFTR J. Manickam, T. Fujita 1 , N Fusion Physics and Technology, Torrance, CA USA Abstract Localized MHD activity observed in JT­60U to an ideal MHD n = 1 instability. The appearance of the instability depends on the local pressure gradient

204

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

NASA Technical Reports Server (NTRS)

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.

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

1996-01-01

205

BIBLIOGRAPHY [AFL] Accardi, L., Frigerio, A., Lewis, J.T., Quantum stochastic processes, Publ. RIMS 18  

E-print Network

, H., Shibata, F., Stochastic theory of a quasiparticle propagating in a dynamically uctuating medium, preprint, Paris 1994. [Bla] Blackadar, B., K-Theory for Operator Algebras, Springer, Heidelberg, 1986. [Boc, Physica A 176 (1991), 581{606. [Fel] Feller, W., An Introduction to Probability Theory and Its

Speicher, Roland

206

JT9D-7A (SP) jet engine performance deterioration trends  

NASA Technical Reports Server (NTRS)

The levels, trends, and causes of engine performance deterioration were investigated. A series of installed engine calibrations (both on-the-ground and in-flight) were performed on two new Pan American World Airways 747 SP aircraft. The performance data gathered covered from before the first flight through approximately 1000 flight cycles and 6900 flight hours. To accomplish the calibrations a special instrumentation system for ground testing of installed engines over a broad power range was used along with performing concurrent in-flight engine calibrations under revenue service conditions. Results of the analysis of the data, which provide a better understanding of short and long term performance deterioration of both engines and modules are presented.

Richter, G. P.; Olsson, W. J.; Andersen, N. B.

1980-01-01

207

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

NASA Technical Reports Server (NTRS)

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.

1975-01-01

208

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

SciTech Connect

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.

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

1986-08-15

209

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

SciTech Connect

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.

Paugh, R.L.

1989-09-15

210

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

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

211

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)

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.

1973-01-01

212

Brady, J.B., Kovaric, D.N., Cheney, J.T., Jacob, L.J., and King, J.T., 2004, 40 Ar ages of metamorphic rocks from the Tobacco Root Mountains region, Montana,  

E-print Network

, Amherst, Massachusetts 01002, USA ABSTRACT Measurements of 60 single-grain, UV laser microprobe 40 Ar/39 that the rocks cooled rapidly through the interval from 500 to 300 °C. This is consistent with a model of the Big by Cretaceous (75 Ma) intrusive rocks. Hydrothermal alteration associated with ca. 1.4 Ga rifting led to growth

Brady, John B.

213

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

Federal Register 2010, 2011, 2012, 2013

...3rd stage and 4th stage low- pressure turbine (LPT) blades for shroud notch wear and...We are proposing this AD to prevent turbine blade failures that could result in uncontained...condition, if not corrected, could result in turbine blade failures that could result in...

2010-07-01

214

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

Federal Register 2010, 2011, 2012, 2013

...3rd stage and 4th stage low- pressure turbine (LPT) blades for shroud notch wear and...effective. We are issuing this AD to prevent turbine blade failures that could result in uncontained...which they state is stage 3/stage 4 LPT turbine blades shroud wear and subsequent...

2011-03-24

215

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

Federal Register 2010, 2011, 2012, 2013

...currently requires cleaning the front compressor front hubs (fan hubs), initial and repetitive eddy current (ECI) and fluorescent penetrant inspections (FPI) of tierod and counterweight holes for cracks, removal of bushings, cleaning and ECI and...

2010-03-18

216

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

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

217

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

NASA Astrophysics Data System (ADS)

Aiming at optimization of current profile in high-? 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-? plasma, where qmin follows the temporally changing reference qmin,ref from 1.3 to 1.7. Applying the control to another high-? discharge (?N = 1.7, ?p = 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 ? 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.

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

218

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

Federal Register 2010, 2011, 2012, 2013

...of cracks in five high-pressure compressor (HPC) shafts. This AD requires removing certain HPC shafts before their certified life limits and...41144). That NPRM proposed to require: For HPC shafts that have more than 4,500...

2011-12-12

219

Mssbauer quantification of pyrrhotite in relation to self-heating A. Navarra a,*, J.T. Graham b  

E-print Network

-heating phenomenon is often accompanied by the release of noxious gasses (H2S, SO, SO2) and acid drainage. Although and Finch (2006), suggesting that Po mobilizes the sulphur within the stockpiles. The sulphur may then be transported to oxygen-rich zones for the exothermic production of SO, SO2, and H2SO4. The catalyzing effect

Ryan, Dominic

220

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

Federal Register 2010, 2011, 2012, 2013

...that the part is not damaged or related to the cause of its removal from the engine. (3) The inspections specified in this section...HP Turbine, First Stage: Rotor Assembly--All P/Ns.... 72-52-02 -04 [[Page...

2011-02-15

221

Computational Forensics: Towards Hybrid-Intelligent Crime Investigation  

E-print Network

Computational Forensics: Towards Hybrid-Intelligent Crime Investigation Katrin Franke and Sargur on Computational Forensics, Manchester, England, August 30, 2007 #12;Computational Forensics: Towards Hybrid-Intelligent Crime Investigation Katrin Franke Norwegian Information Security Laboratory, Gjøvik University College

222

Sensitivity of neutrino mass experiments to the cosmic neutrino background  

E-print Network

The KATRIN neutrino experiment is a next-generation tritium beta decay experiment aimed at measuring the mass of the electron neutrino to better than 200 meV at 90% C.L. Because of its intense tritium source, KATRIN can ...

Formaggio, Joseph A.

223

Nanofilm Allotrope and Phase Transformation of Ultrathin Bi Film on Si111-7 7 T. Nagao,1,2,* J.T. Sadowski,1  

E-print Network

initio calculations, we propose that the new allotrope consists of black phosphorus-like puckered layers-layer structure was never observed before ex- cept for the case of black phosphorus, which is a famous teratoid

Hasegawa, Shuji

224

Particle simulations of energetic particle driven Alfvn modes in JT-60U G. Fogaccia, S. Briguglio, G. Vlad, F. Zonca, K. Shinohara, M. Ishikawa, M. Takechi  

E-print Network

large fluctuating magnetic field level (B /B 10-3 at the first wall) and large growth rates: Contour plots of the power spectrum of the fluctuating scalar potential in the (/A0,r/a) plane (few milliseconds), lower growth rate and fluctuating field level, and much smaller re- distribution

Zonca, Fulvio

225

Particle simulations of energetic particle driven Alfvn modes in JT-60U G. Fogaccia, S. Briguglio, G. Vlad, F. Zonca, K. Shinohara, M. Ishikawa, M. Takechi  

E-print Network

fluctuating magnetic field level (B /B 10-3 at the first wall) and large growth rates (corresponding to wide|| are normalized magnetic moment and parallel velocity. Figure 1: Contour plots of the power spectrum growth rate and fluctuating field level, and much smaller redistribution of the energetic ions. Most

Vlad, Gregorio

226

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

Federal Register 2010, 2011, 2012, 2013

...7B, -9, - 9A, -11, -15, -15A, -17, -17A, -17R, and -17AR Series Turbofan...7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series turbofan...7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series...

2010-08-18

227

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

Federal Register 2010, 2011, 2012, 2013

...7B, -9, - 9A, -11, -15, -15A, -17, -17A, -17R, and -17AR Series Turbofan...7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series turbofan...7B, -9, - 9A, -11, -15, -15A, -17, -17A, -17R, and -17AR series...

2011-01-28

228

TEM Characterization of Crept and Irradiated Nano-structured Ferritic Alloys J. Bentley,* D.T. Hoelzer,* J.T. Busby,* A.G. Certain,  

E-print Network

resistant to radiation damage in fission and fusion environments [1,2], and thus are being characterized also appear to be unchanged after creep testing in air for a remarkable 38,555 h at 800°C and 100 MPa at the IVEM-Tandem Facility of Argonne National Laboratory (ANL) at 25 and 500°C to doses up to 100 dpa. One

Motta, Arthur T.

229

J. theor. Biol. (1997) 186, 1732 00225193/97/090017 + 16 $25.00/0/jt960341 7 1997 Academic Press Limited  

E-print Network

Limited Effect of Pruning on Dendritic Tree Topology JAAP VAN PELT Graduate School Neurosciences Amsterdam of dendritic trees is sensitive to the mode of growth. The effect of removal of branches (``pruning'') on the topological structure of dendritic trees has been studied for several random pruning schemes, namely (i

van Pelt, Jaap

230

Govindjee, University of Illinois, Urbana, USA; J.T. Beatty, University of British Columbia, Vancouver, Canada; H. Gest, Indiana University, Bloomington, USA; J.F.  

E-print Network

transfer, reaction centers, oxygen evolution, light-harvesting and pigment-protein complexes, electron depends. This book should not be missed by anyone interested in photosynthesis: It is a must for all of London, UK (Eds.) Discoveries in Photosynthesis "Life Is Bottled Sunshine" [Wynwood Reade, Martyrdom

Govindjee "Gov"

231

J. theor. Biol. (1997) 184, 203217 00225193/97/020203 + 15 $25.00/0/jt960307 7 1997 Academic Press Limited  

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of HIV-1 replication in vivo. The two major types of anti-HIV drugs are reverse transcriptase inhibitors and protease inhibitors. Reverse transcriptase inhibitors prevent the infection of new cells by blocking. Introduction In recent years, a number of anti-viral drugs have been developed that are potent inhibitors

Bonhoeffer, Sebastian

232

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)

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.

Hambly, D.

1974-01-01

233

J. theor. Biol. (1997) 188, 121126 00225193/97/170121 + 06 $25.00/0/jt970458 7 1997 Academic Press Limited  

E-print Network

, Vinicna 7, CZ-128 44 Prague, Czech Republic (Received on 26 March 1997, Accepted on 17 April 1997-strategy is often considered an adaptation for living in unstable or unpredictable environments, e.g., resource-rich the optimal adaptation*E-mail: FLEGR.MBOX.CESNET.CZ #12;J. FLEGR122 for living in stable or predictable

Flegr, Jaroslav

234

IEEE TRANSACTIONS ON AUTOMATION SCIENCE AND ENGINEERING, VOL. 4, NO. 1, JANUARY 2007 79 [10] J.-T. Lim and S. M. Meerkov, "On asymptotic reliable closed serial  

E-print Network

, vol. 1, pp. 147­152, 1993. [11] J. Li, "Throughput analysis in automotive paint shops: a case study. Narahari and N. Viswanadham, "Transient analysis of manufac- turing systems performance," IEEE Trans. Robot. Gopalakrishna, "Performa- bility studies of manufacturing systems with multiple part types," IEEE Trans. Robot

235

J. theor. Biol. (1998) 192, 155166 00225193/98/100155 + 12 $25.00/0/jt970590 7 1998 Academic Press Limited  

E-print Network

, 1977; Trivers, 1971) and vampire bats (Wilkinson, 1984). In the former case two young male baboons of mounting an oestrous female. In the latter situation well fed vampire bats regurgitate some blood to feed

Hauert, Christoph

236

Small ELM regimes with good confinement on JET and comparison to those on ASDEX Upgrade, Alcator C-mod and JT-60U  

Microsoft Academic Search

Since it is uncertain if ITER operation is compatible with type-I edge localized modes (ELMs), the study of alternative ELM regimes is an urgent issue. This paper reports on experiments on JET aiming to find scenarios with small ELMs and good confinement, such as the type-II ELMs in ASDEX Upgrade, the enhanced D-alpha H-mode in Alcator C-mod or the grassy

J. Stober; P. J. Lomas; G. Saibene; Y. Andrew; P. Belo; G. D. Conway; A. Herrmann; L. D. Horton; M. Kempenaars; H.-R. Koslowski; A. Loarte; G. P. Maddison; M. Maraschek; D. C. McDonald; A. G. Meigs; P. Monier-Garbet; D. A. Mossessian; M. F. F. Nave; N. Oyama; V. Parail; Ch. P. Perez; F. Rimini; R. Sartori; A. C. C. Sips; P. R. Thomas; Contributors to the EFDA-JET workprogramme

2005-01-01

237

Small ELM regimes with good connement on JET and comparison to those on ASDEX Upgrade, Alcator C-mod, and JT-60U  

Microsoft Academic Search

Since it is uncertain if ITER operation is compatible with type-I ELMs, the study of alternative H-mode pedestals is an urgent issue. This paper reports on experiments on JET aiming to nd scenarios with small ELMs and good connement, such as the type-II ELMs in ASDEX Upgrade, the enhanced D- alpha H-mode in Alcator C-mod or the grassy ELMs in

J. Stober; P. Lomas; G. Saibene; Y. Andrew; P. Belo; G. D. Conway; L. D. Horton; M. Kempenaars; H.-R. Koslowski; A. Loarte; G. P. Maddison; M. Maraschek; D. C. McDonald; A. G. Meigs; P. Monier-Garbet; D. A. Mossessian; M. F. F. Nave; N. Oyama; V. Parail; Ch. P. Perez; F. Rimini; R. Sartori; A. C. C. Sips; P. R. Thomas

238

Source : Philippe Poirrier, Culture populaire et politique culturelle en France : un rendez-vous manqu ? dans Thomas ANTONIETTI, Bruno MEIER et Katrin RIEDER (dir.), Retour vers le prsent. La culture populaire en Suisse, Baden,  

E-print Network

Source : Philippe Poirrier, « Culture populaire et politique culturelle en France : un rendez culture populaire en Suisse, Baden, Hier+jetzt, Verlag für Kultur und Geschichte, 2008, p. 176-183. Culture populaire et politique culturelle en France : un rendez-vous manqué ? Comment la politique

Paris-Sud XI, Université de

239

Validation of a model for radon-induced background processes in electrostatic spectrometers  

NASA Astrophysics Data System (ADS)

The Karlsruhe Tritium Neutrino (KATRIN) experiment investigating tritium ?-decay close to the endpoint with unprecedented precision has stringent requirements on the background level of less than 10-2 counts per second. Electron emission during the ?-decay of 219, 220Rn atoms in the electrostatic spectrometers of KATRIN is a serious source of background exceeding this limit. In this paper we compare extensive simulations of Rn-induced background to specific measurements with the KATRIN pre-spectrometer to fully characterize the observed Rn-background rates and signatures and determine generic Rn emanation rates from the pre-spectrometer bulk material and its vacuum components.

Wandkowsky, N.; Drexlin, G.; Fränkle, F. M.; Glück, F.; Groh, S.; Mertens, S.

2013-08-01

240

Harms, T.A., Brady, J.B., Burger, H.R., and Cheney, J.T., 2004, Advances in the geology of the Tobacco Root Mountains, Montana, and their implications for the history of the northern Wyoming province, in Brady, J.B., Burger, H.R., Cheney, J.T., and Harms,  

E-print Network

of the Tobacco Root Mountains, Montana, and their implications for the history of the northern Wyoming province, and their implications for the history of the northern Wyoming province Tekla A. Harms Department of Geology, Amherst with associated metasupracrustal rocks (the combined Indian Creek and Pony­Middle Mountain Metamorphic Suites

Brady, John B.

241

An analytic study of the E ? e Jahn-Teller polaron  

Microsoft Academic Search

:   An analytic study is presented of the E?e Jahn-Teller (JT) polaron, consisting of a mobile eg electron linearly coupled to the local eg normal vibrations of a periodic array of octahedral complexes. Due to the linear coupling, the parity operator and the angular momentum operator commute with the JT part and cause a twofold degeneracy of each JT eigenvalue.

Heinz Barentzen

2001-01-01

242

Stuttgart University The Department of  

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, land surveying and engineering and engineering surveys, telematics, photogrammetry, remote sensing, optical inspection, geographic information systems and location based services in research, development.-Ing. Katrin Ramm Kinematic positioning Dipl.-Ing. Ralf Schollmeyer Vehicle positioning Dr.-Ing. Volker

Möbius, Bernd

243

Proceedings of the 52nd Annual Meeting of the Association for Computational Linguistics, pages 12101219, Baltimore, Maryland, USA, June 23-25 2014. c 2014 Association for Computational Linguistics  

E-print Network

Soft Logic for Semantic Textual Similarity Islam Beltagy� Katrin Erk Raymond Mooney� � Department representation of meaning, which can then be re- laxed in a controlled fashion using distributional similarity

244

Sensitivity of neutrino mass experiments to the cosmic neutrino background  

SciTech Connect

The KATRIN neutrino experiment is a next-generation tritium beta decay experiment aimed at measuring the mass of the electron neutrino to better than 200 meV at 90% C.L. Because of its intense tritium source, KATRIN can also serve as a possible target for the process of neutrino capture, {nu}{sub e}+{sup 3}H{yields}{sup 3}He{sup +}+e{sup -}. The latter process, possessing no energy threshold, is sensitive to the cosmic neutrino background (C{nu}B). In this paper, we explore the potential sensitivity of the KATRIN experiment to the relic neutrino density. The KATRIN experiment is sensitive to a C{nu}B overdensity ratio of 2.0x10{sup 9} over standard concordance model predictions (at 90% C.L.), addressing the validity of certain speculative cosmological models.

Kaboth, A.; Formaggio, J. A.; Monreal, B. [Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States); Department of Physics, University of California, Santa Barbara, Santa Barbara, California (United States)

2010-09-15

245

A robust automated system elucidates mouse home cage behavioral structure  

E-print Network

. Katrin Schenkb , Punita Junejaa , Adrienne W. MacKaya , Jennifer M. Wadea , and Laurence H. Tecotta,1 a capture the rich temporal and spatial structure of diverse behaviors that occur over multiple time scales

Jiggins, Francis

246

Building Virtual Earth Observatories using Ontologies, Linked Geospatial Data and  

E-print Network

Discovery Algorithms Manolis Koubarakis1 , Michael Sioutis1 , George Garbis1 , Manos Karpathiotakis1 Dumitru2 , Daniela Espinoza Molina2 , Katrin Molch2 , Gottfried Schwarz2 , and Mihai Datcu2 1 National

Koubarakis, Manolis

247

Image Based Characterization of Circulating Tumor Cells  

E-print Network

Image Based Characterization of Circulating Tumor Cells Katrine Brandt Albrektsen CY T O T R A C K;Abstract he ssessment of irulting tumor ells @ggsA in lood smples from ner ptients n help in determining

248

Zrich, den 22. Dezember 2005 Bildungsdirektion  

E-print Network

-Katrin, aus/in Deutschland ,,Landnutzung in Baden-Württemberg als Einflussfaktor auf die Echinococcus multilocularis-Prävalenz bei Rotfüchsen" Zürich, den 22. Dezember 2005 Der Dekan: U. Hübscher #12

Zürich, Universität

249

Photoluminescence properties of Jahn-Teller transition-metal ions  

NASA Astrophysics Data System (ADS)

This work investigates the influence of electron-phonon coupling associated with E ?e and T ?e Jahn-Teller (JT) effect in different transition-metal (TM) ions on de-excitation phenomena through nonradiative multiphonon relaxation, i.e., photoluminescence (PL) quenching. We developed a configurational curve model which is able to predict from the absorption spectrum whether a given JT-TM ion is PL or quenched. The prediction is made on the basis of an adapted Dexter-Klick-Russell parameter for JT systems, defined in terms of spectroscopic parameters through ?JT=??eabs/Eabs, where ?eabs refers to the splitting of the parent octahedral Eg states by the JT distortion in E ?e (? =3/4) or T ?e (? =1/4), and Eabs is the energy of the first absorption band involving electronic transition between Eg and T2g. We show that PL in any JT-TM ion occurs whenever ?JT<0.1 or is quenched if ?JT>0.2. This result is noteworthy since it allows us to establish structural requirements for the JT-TM ion and the host crystal to be PL. Although PL properties of materials containing TM ions depend on a variety of structural factors such as the electronic configuration, the site symmetry, and the crystal field produced by neighboring atoms, the present model achieves this goal through a simple spectroscopic parameter: ?JT. In this work we correlated the PL properties of different sixfold-coordinated JT systems such as Ti3+, Cu2+, Mn3+, Cr2+, Fe2+, Co3+, and Ni3+ in halides and oxides with ?JT obtained from their respective absorption spectra. From this analysis we conclude that depending on the nature of the JT coupling and its strength, PL is either strongly favored or quenched in T ?e while it is mostly quenched in E ?e systems due to the larger JT distortion.

Sanz-Ortiz, Marta N.; Rodríguez, Fernando

2009-09-01

250

Academic Advising & Career Centre: A team of professionals who advise, counsel and coach individuals with their learning and career development. September 2010, source; jt. Academic Advising & Career Centre. All Rights Reserved.  

E-print Network

More Control, Less Stress. Good time management means not waiting until the last minute and rushing & Career Centre. All Rights Reserved. Time Management How do you use the 168 hours you have in one week), commit yourself to what you schedule and follow through on your intentions. Benefits of Time Management

Boonstra, Rudy

251

Comment on 'Observations of reconnection of interplanetary and lobe magnetic field lines at the high-latitude magnetopause' by J.T. Gosling, M.F. Thomsen, S.J. Bame, R.C. Elphic, and C.T. Russell  

NASA Technical Reports Server (NTRS)

Comment is presented on the results of measurements, reported by Gosling et al. (1991), that were made on ISEE in the vicinity of the high-latitude dusk magnetopause near the terminator plane, at a time when the local magnetosheath and tail lobe magnetic fields were nearly oppositely directed. The character of the observed plasma flowing both tailward and sunward within the high-latitude magnetopause current layer presented real evidence for the local reconnection process. Gosling et al. argued that this process may be a manifestation of different global magnetospheric topology structures. In the comment, a global magnetospheric convection pattern is constructed for the northward IMF and for the case of a large azimuthal component of the IMF with small Bz, irrespective of its sign. The suggested scheme provides a simple explanation for the observed sunward convection in the polar caps both for the northward and for strong By with small Bz. According to the present model, for the magnetosheath field at 2300 UT on June 11, 1978, the reconnection between the open field lines appears at the northern neutral point.

Belen'kaia, Elena

1993-01-01

252

Academic Advising & Career Centre: A team of professionals who advise, counsel and coach individuals with their learning and career development. September 2010, source; jt. Academic Advising & Career Centre. All Rights Reserved.  

E-print Network

best by hearing; printed handouts for the visual learners; and exercises and activities for those whose and resources. These services and resources are offered in ways that are suited to different kinds of learners strengthen your current study skills. Our peer counsellors can help learners of all types through discussion

Boonstra, Rudy

253

Revised CB/JT December 19, 2013 Please Note: This Course Syllabus is an important step in updating the format of our distance courses. If for any reason the Course  

E-print Network

as the research literature. · Have a comprehensive knowledge base for working with students who are learning System 4. Remembering to Learn and Learning to Remember: Our Memory System 5. Ways with Words: Our COURSE TITLE: Supporting Students with Learning Disabilities COURSE CODE: EPSE 520.3 TERM: Winter Term 2

Saskatchewan, University of

254

Contact Information: Dr. Paul D. Baxter, Department of Statistics, University of Leeds, Leeds, LS2 9JT, UK; 44 133 343 5162; Email: pdbaxt@maths.leeds.ac.uk; Web: http://www.maths.leeds.ac.uk/ pdbaxt  

E-print Network

. 5 Food-limited regime: ¢¦¦¥§© Patchiness increases the variability in the time to critical mass advantage. 1500 2500 3500 4500 0.0000.010 Time to maturity Density Fig. 2 Food-limited regime: ¢¦¦¥§© Time flexible model of larval growth, that encapsulates the random nature of the process, and yet respects

Baxter, Paul D.

255

Academic Advising & Career Centre: A team of professionals who advise, counsel and coach individuals with their learning and career development. September 2010, source; jt. Academic Advising & Career Centre. All Rights Reserved.  

E-print Network

-doubt. In order to see test writing as a positive experience it is important to be well prepared, to be well the Exam Begins Look After Your Physical Well-Being. It is important that you are well rested in order and may even fall asleep, using up precious test-writing time. It is equally important that you eat

Boonstra, Rudy

256

Academic Advising & Career Centre: A team of professionals who advise, counsel and coach individuals with their learning and career development. September 2010, source; jt. Academic Advising & Career Centre. All Rights Reserved.  

E-print Network

& Career Centre. All Rights Reserved. Learning Styles Learning is important! Learning is a process which of the ways that you can maximize your learning is by becoming aware of your learning style(s). Some students will have one learning style which is most dominant for them while others will have more than one area

Boonstra, Rudy

257

Academic Advising & Career Centre: A team of professionals who advise, counsel and coach individuals with their learning and career development. September 2010, source; jt. Academic Advising & Career Centre. All Rights Reserved.  

E-print Network

& Career Centre. All Rights Reserved. Goal Setting Goal setting is one of the cornerstones of personal life. Set goals and work toward them but enjoy the process of attaining your goals along the way. Types before it is due. Personal/Social Goals. These goals might include such things as spending more time

Boonstra, Rudy

258

Dale Meade Some promised international collaboration info  

E-print Network

to first data, upon arrival in Japan. http://wsx.lanl.gov/scifi.htm http://www-jt60.naka.jaea.go.jp/english/html/exp_rep/remoted.html http://www-jt60.naka.jaea.go.jp/english/html/exp_rep/rep38.html http://www-jt60.naka.jaea.go.jp/english/annual/96/html/an96-I4.html A little bit later, I took an infrared imaging bolometer over to LHD. My primary

259

Double degeneracy and Jahn-Teller effects in colossal-magnetoresistance perovskites  

Microsoft Academic Search

Jahn-Teller (JT) electron-phonon-coupling effects in the colossal-magnetoresistance perovskite compounds La1-xAxMnO3 are investigated. Electron-electron correlations between two degenerate Mn eg orbitals are studied in the Gutzwiller approximation. The static JT distortion and nonadiabatic polaron effects are studied in a modified Lang-Firsov approximation. We find that (i) the electron or hole character of the charge carrier depends on the static JT distortion

Jun Zang; A. R. Bishop; H. Roeder

1996-01-01

260

Isolation and identification of phytate-degrading bacteria and their contribution to phytate mineralization in soil.  

PubMed

To better understand the phosphorus (P) cycling in an agricultural soil environment, amounts of total, organic and inorganic P in 10 agricultural soil samples were analyzed. Since a large proportion (57.8%) of the total P in the soils was in organic form, a method was developed to evaluate the mineralization rate of organic P in the soil by adding phytate to the soil and analyzing the change in water-soluble P (WSP) content after incubating it for 3 days. Moreover, the relationship between the phytate mineralization activity and bacterial biomass in 60 agricultural soils was also investigated, where the phytate mineralization activity ranged from 0 to 61.7% (average: 18.8%), and the R² value between phytate mineralization activity and indigenous bacterial biomass was 0.11 only. Phytate-degrading bacteria were isolated from the soil environment, and identified as Pseudomonas rhodesiae JT29, JT32, JT33, JT34, JT35, Pseudomonas sp. JT30, and Flavobacterium johnsoniae JT31. When P. rhodesiae JT29 and F. johnsoniae JT31 were inoculated into the agricultural soils, the phytate mineralization activities were increased up to 16 and 27 times, respectively. It was concluded that promotion of effective phytate-degrading bacterial strains could improve the sustainable P management in the agricultural soils. PMID:24201147

Horii, Sachie; Matsuno, Toshihide; Tagomori, Junta; Mukai, Masaki; Adhikari, Dinesh; Kubo, Motoki

2013-01-01

261

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

NASA Astrophysics Data System (ADS)

Using the framework of multiconfiguration theory, where the wavefunction ?(t) of a many-electron system at time t is expanded as ? (t) = sumnolimits_I {C_I (t)? _I (t)} in terms of electron configurations {?I(t)}, we divided the total electronic energy E(t) as E (t) = sumnolimits_I\\vert {C_I (t)\\vert^2 E_I (t)} . Here EI(t) is the instantaneous phase changes of CI(t) regarded as a configurational energy associated with ?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 {EI(t)} associated with the quantum phases of CI(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 ?j(t) for time-dependent natural orbitals ?j(t) of a many-electron system. The analysis of the electron dynamics of LiH indicated that the temporal change in ??j(t) ? ?j(t) + ?(t) . dj(t) - ?j(0) correlates with the motion of the dipole moment of ?j(t), dj(t). The values ??j(t) are much larger than the energy ?j(t) directly supplied to ?j(t) by the field, suggesting that valence electrons exchange energy with inner shell electrons. For H2 in an intense near-IR field, the ionization efficiency of ?j(t) is correlated with ??j(t). Comparing ??j(t) to ?j(t), we found that energy accepting orbitals of ??j(t) > ?j(t) indicate high ionization efficiency. The difference between ??j(t) and ?j(t) is significantly affected by electron-electron interactions in real time.

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

2014-09-01

262

Portfolio screening to support the mainstreaming of adaptation to  

E-print Network

assistance Richard J.T. Klein, Siri E.H. Eriksen, Lars Otto Næss, Anne Hammill, Thomas M. Tanner, Carmenza assistance Richard J.T. Klein1* , Siri E.H. Eriksen2 , Lars Otto Næss3,4 , Anne Hammill5 , Thomas M. Tanner6

Watson, Andrew

263

Engine component improvement program: Performance improvement. [fuel consumption  

NASA Technical Reports Server (NTRS)

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.

Mcaulay, J. E.

1979-01-01

264

Understanding the use of intimidation as a response to job tension : Career implications for the global leader  

Microsoft Academic Search

Purpose – The purpose of this paper is to investigate the relationship between job tension (JT) and the use of intimidation in the workplace, as well as positive and negative affectivity as two potential personality trait moderators of this relationship. Design\\/methodology\\/approach – The paper hypothesizes that employees would use more intimidation when they perceive higher levels of JT based on

Vickie Coleman Gallagher; Kenneth J. Harris; Matthew Valle

2008-01-01

265

J. Thomas Farrar December 10, 2008 Assistant Scientist  

E-print Network

002989. Plueddemann, A.J. and Farrar, J.T. 2006. Observations and models of the energy flux from the wind. Meteor. Soc., 88(3), 341-356. Farrar, J.T., Zappa, C.J., Weller, R.A., and Jessup, A.T. 2007. Sea surface

Yu, Lisan

266

10.1101/gr.071886.107Access the most recent version at doi: 2008 18: 717-728; originally published online Mar 13, 2008;Genome Res.  

E-print Network

, Heidi J.T. Pagan, Jeremy D. Smith, Ellen J. Pritham, Peter Arensburger, lucifugus MyotisMultiple waves bywww.genome.orgDownloaded from #12;Multiple waves of recent DNA transposon activity in the bat, Myotis lucifugus David A. Ray,1,5,6 Cedric Feschotte,2,5 Heidi J.T. Pagan,1 Jeremy D. Smith,1 Ellen J. Pritham,2

Feschotte, Cedric

267

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

PubMed

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 (?qseB) mutant and lsrRK double deletion mutants (?lsrRK). 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

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

2013-05-01

268

for 2014 FESAC Strategic Planning Panel Meeting, 8th July, 2014  

E-print Network

towards DEMO, by addressing key physics issues for ITER and DEMO. #12;JT-60SA: First Plasma in Mar. 2019 Target 10020 40 60 80 DEMO reactors ITER ITER N Existing Tokamaks JT-60U Steady-state Inductive FB ideal & demonstrate a practical set of DEMO plasma controls. We treat `the DEMO regime' as a spectrum. 0 1 2 3 4 5

269

UFR Sciences et Techniques Licence STS mention Informatique -semestres 3 et 4 MCC 2013-2014 C. Cont session 2 O/N C. Cont  

E-print Network

Veronique RENAULT UT 3 TAN 18 L2 PC/MA/SI 100% oral/écrit O 100% 0% oral/écrit JT3ARCHI Architecture 27 21 39 100% oral/écrit O 1h30 oral/écrit 60% 40% 1h30 oral/écrit JT4PROGS Système et programmation

Jeanjean, Louis

270

BIOGRAPHICAL SKETCH Provide the following information for the key personnel and other significant contributors in the order listed on Form Page 2.  

E-print Network

Dis. 1998 Jul;178(1):8-15. 4. Terhune SS, Milcarek C, Laimins LA. Regulation of human papillomavirus. Terhune SS, Hubert WG, Thomas JT, Laimins LA. Early polyadenylation signals of human papillomavirus type(9):7185-92. 5. Thomas JT, Oh ST, Terhune SS, Laimins LA. Cellular changes induced by low-risk human

271

Instability and re-entrant behaviour of Jahn-Teller distortion due to induced magnetization in manganites  

NASA Astrophysics Data System (ADS)

In the hole doped rare-earth manganites there exists a competition between the double exchange (DE) interaction and Jahn-Teller (JT) distortion, which leads to metal-insulator (MI) transition. The DE interaction promotes a ferromagnetic metallic phase, whereas JT distortion promotes an insulating phase. For a set of s-d type DE, JT and Heisenberg coupling parameters, the lattice strain produced due to JT distortion exhibits a re-entrant type behaviour and the system becomes unstable. In this paper we have studied the evolution of the re-entrant behaviour and instability in manganites. It is observed that the instability in the system is mainly due to the cross over of energy bands. Two temperature dependent resistivity peaks are observed in the JT insulating phase, when re-entrant behaviour is seen.

Panda, Saswati; Rout, G. C.; Behera, S. N.

2012-07-01

272

Double degeneracy and Jahn-Teller effects in colossal-magnetoresistance perovskites  

SciTech Connect

Jahn-Teller (JT) electron-phonon-coupling effects in the colossal-magnetoresistance perovskite compounds La{sub 1{minus}{ital x}}{ital A}{sub {ital x}}MnO{sub 3} are investigated. Electron-electron correlations between two degenerate Mn {ital e}{sub {ital g}} orbitals are studied in the Gutzwiller approximation. The static JT distortion and nonadiabatic polaron effects are studied in a modified Lang-Firsov approximation. We find that (i) the electron or hole character of the charge carrier depends on the static JT distortion and (ii) due to the two-component nature of the JT coupling, fluctuations in the JT distortion direction contribute to the charge transport in similar fashion as the local spins. {copyright} {ital 1996 The American Physical Society.}

Zang, J.; Bishop, A.R.; Roeder, H. [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

1996-04-01

273

Stuttgart University The Department of  

E-print Network

, remote sensing, engi- neering surveying and telematics to photogrammetry, geographical information systems and lo- cation based services. Detailed information can be found in the following individual Dipl.-Ing. Katrin Ramm (till 30.04.2007) Kinematic positioning Dipl.-Ing. Ralf Schollmeyer Vehicle

Möbius, Bernd

274

Landesschulamt Stand: 14.02.2013 Prfungsstelle Darmstadt  

E-print Network

Deutsch 28.02.2015 Prof. Dr. Jens Ivo Engels Geschichte 28.02.2015 Prof. Dr. Stefan Evert Englisch 31 Luserke-Jaqui Deutsch 28.02.2015 Dr. Jan Müller Philosophie / Ethik 28.02.2015 Dipl.Math. Katrin Müller

Hoffmann, Rolf

275

Genet. Sel. Evol. 35 (Suppl. 1) (2003) S3S17 S3 INRA, EDP Sciences, 2003  

E-print Network

to control the transmission of infection through an animal population. Transmission is summarised by R0 homogeneous population comprising animals of these two groups, R0 is the weighted average of the two sub-populations populations Stephen C. BISHOP , Katrin M. MACKENZIE Roslin Institute (Edinburgh), Roslin, Midlothian, EH25 9

Boyer, Edmond

276

A 1,000-year sediment record of tsunami recurrence in northern Sumatra  

E-print Network

LETTERS A 1,000-year sediment record of tsunami recurrence in northern Sumatra Katrin Monecke1 province of Sumatra1,2 . Both the tsunami and the associated Sumatra­ Andaman earthquake were unprecedented of AD 1907. These findings, a first step towards a palaeotsunami record for northern Sumatra, suggest

277

International Joint Research Project "Physical Violence and State Legitimacy in Late Socialism"  

E-print Network

at the Institute 19.45 Film 4 Months, 3 Weeks and 2 Days (4 luni, 3 sptmâni i 2 zile) (Romania 2007, 113 min Marginean's Bless You, Prison and Cristian Mungiu's 4 Months, 3 Weeks and 2 Days Katrin Boeckh, IOS, IICCMER, Bucharest Psychiatry as Political Violence in Communist Romania Jennifer Rasell, ZZF Potsdam Lost

Schubart, Christoph

278

Dynamic management of water transfer between two interconnected river basins  

E-print Network

determined by the Spanish government. Keywords: inter- basin water transfer; differential game; NashDynamic management of water transfer between two interconnected river basins Francisco Cabo Katrin regions with interconnected river basins. Precipitation is higher in one river-basin while water

Boyer, Edmond

279

bersicht ber evaluierte Lehrveranstaltungen und Dozierende der Lehreinheit Textiles Gestalten Seite 1 von 2 Anrede Vorname Name Anmel  

E-print Network

�bersicht über evaluierte Lehrveranstaltungen und Dozierende der Lehreinheit Textiles Gestalten Lehreinheit Frau Patricia Mühr nein Textiles Gestalten Frau Hiltrud Schäfer nein Textiles Gestalten Frau Hiltrud von der Heyde nein Textiles Gestalten Frau Katrin Gausmann nein Textiles

Kallenrode, May-Britt

280

Fabrication and Test of Ferromagnetic Single-Electron-Transistors  

E-print Network

. It provides fast and accurate electrical test results for multiple devices built into standard 16-pad test cages, essentially eliminating the test from the overall processing time. The test system was usedFabrication and Test of Ferromagnetic Single-Electron-Transistors Diploma Thesis Katrin Pappert

Haviland, David

281

Factored Neural Language Models Andrei Alexandrescu  

E-print Network

Factored Neural Language Models Andrei Alexandrescu Department of Comp. Sci. Eng. University of Washington katrin@ee.washington.edu Abstract We present a new type of neural proba- bilistic language model that learns a map- ping from both words and explicit word features into a continuous space that is then used

Kirchhoff, Katrin

282

Documents de Travail du Centre d'Economie de la Sorbonne  

E-print Network

Emissions from the Swedish Pulp and Paper Industry and Energy Sector Asa L�FGREN, Katrin MILLOCK, Céline of Abatement Investments - An Application to Sulfur Emissions from the Swedish Pulp and Paper Industry Investments - An Application to Sulfur Emissions from the Swedish Pulp and Paper Industry and Energy Sector1

Paris-Sud XI, Université de

283

Curriculum vitae -Heinz Koeppl General Information  

E-print Network

Curriculum vitae - Heinz Koeppl General Information Name Heinz K¨oppl Date of birth March 20, 1975 Place of birth Friesach, Austria Marital status Married to Katrin, daughters Jasmin (2005) and Iris assistant at the Christian Doppler Laboratory for Nonlinear Signal Pro- cessing, Graz University

Lygeros, John

284

Brief Interruption of Blood Supply to Limb Might Aid Heart Surgery  

MedlinePLUS

... Heart Surgery: Study Technique can trigger body's defense system to protect the heart, experts say (*this news item will not be available after 01/22/2015) By Mary Elizabeth Dallas Friday, October 24, ... by mobilizing its defense system," said the study's first author, Dr. Katrine Hordnes ...

285

NERI Technical Report No. 703, 2009 Projection of  

E-print Network

, Ministry of Climate and Energy Financial support: Danish Environmental Protection Agency Please cite as individual policy measures. Official Danish forecasts of activity rates are used in the models for those, HFCs, PFs and SF6 Layout: Ann-Katrine Holme Christoffersen ISBN: 978-87-7073-081-5 ISSN (electronic

286

Conditions for detecting CP violation via neutrinoless double beta decay  

E-print Network

Neutrinoless double beta decay data together with information on the absolute neutrino masses obtained from the future KATRIN experiment and/or astrophysical measurements give a chance to find CP violation in the lepton sector with Majorana neutrinos. We derive and discuss necessary conditions which make discovery of such CP violation possible for the future neutrino oscillation and mass measurements data.

Alicja Joniec; Marek Zralek

2004-11-04

287

COMBINING ARTICULATORY AND ACOUSTIC INFORMATION FOR SPEECH RECOGNITION IN NOISY AND REVERBERANT  

E-print Network

COMBINING ARTICULATORY AND ACOUSTIC INFORMATION FOR SPEECH RECOGNITION IN NOISY AND REVERBERANT 100 131, 33501 Bielefeld, Germany katrin@techfak.uni­bielefeld.de ABSTRACT Robust speech recognition. 1. INTRODUCTION Whereas most speech recognition systems use a cepstral or spec­ tral representation

Kirchhoff, Katrin

288

GRAPHICAL MODEL REPRESENTATIONS OF WORD LATTICES Jeff Bilmes,  

E-print Network

for expressing word lattices within a dynamic graphical model. We describe a variety of choices for doing thisGRAPHICAL MODEL REPRESENTATIONS OF WORD LATTICES Gang Ji, Jeff Bilmes, Jeff Michels, Katrin. The approach was imple- mented as part of the graphical model toolkit, and word error rate improvements

Bilmes, Jeff

289

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

NASA Astrophysics Data System (ADS)

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.

Jurns, J. M.

2010-04-01

290

Mixed refrigerant Joule-Thomson sorption cryocoolers  

NASA Astrophysics Data System (ADS)

Joule-Thomson (JT) sorption cryocooling is the most mature technology for cooling from a normal Room-Temperature (RT) down to temperatures below 100 K in the absence of moving parts. Therefore, high reliability and no vibrations are attainable, in comparison with other cryocoolers. Cooling to 80 - 100 K with JT cryocoolers is often implemented with pure nitrogen. Alternatively, mixed refrigerants have been suggested for reducing the operating pressures to enable closed cycle cryocooling. There is a variety of publications describing nitrogen sorption cryocoolers with different configurations of sorption compressors. In the present research we suggest a novel sorption JT cryocooler that operates with a mixed refrigerant. Merging of sorption cryocooling and a mixed refrigerant enables the use of a simple, single stage compressor for cooling to 80 - 100 K, lower operating temperatures of the sorption cycle, and thus - reduced power consumption. In previous studies we have analyzed sorption compressors for mixed gases and mixed refrigerants for JT cryocoolers, separately. In this paper the option of mixed refrigerant sorption JT cryocoolers is explored. The considerations for developing mixed refrigerants to be driven by sorption compressors and to be utilized with JT cryocoolers are provided. It appears that, unlike with pure nitrogen, mixed refrigerants can be suitable for JT cryocooling with a single stage sorption compressor.

Tzabar, Nir; Grossman, Gershon

2014-01-01

291

UFR Sciences et Techniques Licence STS mention Sciences pour l'Ingnieur -semestres 5 et 6 MCC 2013-2014 C. Cont session 2 O/N C. Cont  

E-print Network

63 8 10 12 L3 PC 100% oral/écrit O 1h30 L3 PC 60% 40% oral/écrit JT6PSYSE Programmation systèmes.Leblois UE 6 63 24 24 21 100% oral/écrit O 3h 70% JT5MICO Programmation microcontroleur M.Bernier UE 3 63 7 8% oral/écrit O 1h30 60% JT5PRINS Programmation instrumentation F.Chollet UE 3 63 3 27 100% oral/écrit O 1

Jeanjean, Louis

292

Television and Reading Achievement.  

ERIC Educational Resources Information Center

Reports on a survey of 78 seventh-grade students, conducted to investigate the relationship between television viewing and reading achievement. Notes that good readers' viewing habits were not significantly different from those of poor readers. (JT)

Moldenhauer, Deborah L.; Miller, Wilma H.

1980-01-01

293

Neoclassical simulations of fusion alpha particles in pellet charge exchange experiments on the Tokamak Fusion Test Reactor  

E-print Network

with measurements of the alpha distribution function made with a sensitive active neutral particle diagnostic burnup experiments at JT-60U [2]. Both these observations support the assertion that suprathermal ions

294

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, ...

295

75 FR 39046 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance  

Federal Register 2010, 2011, 2012, 2013

...May 10, 2009. Fremont Media Research Center, Leased...May 17, 2009. Inc., Media Operations Division...Idearc Media, LLC, SuperMedia Information...Starting Over Services Crisis Center...JT Sports,...

2010-07-07

296

Liste der Originalpublikationen nach der Habilitation Schmitt R, Westhoff-Bleck M, Haller H, Wagner AD. Paradoxical renal embolism in a  

E-print Network

, Haubitz M, Kielstein JT. Fish, flesh and good red herring: A case of ascending upper limb infection in a renal transplant patient. Clinical Nephrology 71:145-148, 2009. Njau F, Geffers R, Thalmann J, Haller H

Manstein, Dietmar J.

297

Affirmative Action in the Academic Community  

ERIC Educational Resources Information Center

Discusses implementation of an affirmative action plan from the standpoint of the personnel office, recommending centralization of the recruitment and selection process, education of the academic community, and enlistment of their involvement in rectifying their own practices. (JT)

Robustelli, Joseph A.; Ericsson, Carl W.

1975-01-01

298

Answers to PSACI-PAC charge from CPES  

E-print Network

and Enabling Techology Centers 1. TOPS: Provided solvers and algorithms 2. SDM: Kepler work flow and dashboard (MIT), Groebner, Leonard , Osborn (GA), Kamada (JT60U), Horton (ASDEX-U), Fundamenski (JET). We

299

Evidence for a genetic mechanism of the chromogranin A and phenylethanolamine-N-methyltransferase genes in the pathogenesis of hypertension in the spontaneously hypertensive rat  

E-print Network

T: Decreased superoxide dismutase activity and increasedJT: Superoxide dismutase gene expression and activity in theactivity of su- peroxide dismutase (Sod) in many but not all tissues. 37– 43 Superoxide

Friese, Ryan Scott

2007-01-01

300

Teaching a Second Language to Indochinese Refugees When No Program Exists.  

ERIC Educational Resources Information Center

Discusses some of the inherent problems of teaching Indochinese refugees in schools without ESL (English as a Second Language) programs. Considers the strengths and weaknesses of using the language experience approach with Indochinese refugees. (JT)

Deem, James M.; Marshall, W. J.

1980-01-01

301

ESM Peer-reviewed Publications 2006-Present Chang, H., I-W. Jung, A.L. Strecker, D. Wise, M. Lafrenz, V. Shandas, H. Moradkhani, A. Yeakley, Y.  

E-print Network

JT, de Rivera CE (2013) Seawater temperature mediates the biological erosion and plastic pollution polystyrene floats under docks polluting marine waters with microplastic. Mar Poll Bul 64: 1821-1828 Davidson

302

The ScienceDirect TOP25 Hottest Articles is a free  

E-print Network

traits in dogs · Article Animal Behaviour, Volume 69, Issue 2, 1 February 2005, Pages 283-291 Svartberg.; Dietrich, V.; Winkel, W.; Epplen, J.T.; Lubjuhn, T. .6 Play fighting does not affect subsequent fighting

McGraw, Kevin J.

303

The Vo-Ag Spring Educational Trip  

ERIC Educational Resources Information Center

A vocational agriculture teacher discusses values, planning procedures, and logistics of an annual 6-day trip in which 40 Future Farmers of America (FFA) members visit farms, ranches, agribusiness units, and other points of interest to rural oriented youth. (JT)

Fanning, T. D.

1977-01-01

304

Service-Oriented Approach to Collaborative Visualization Haoxiang Wang, Ken Brodlie, James Handley, Jason Wood  

E-print Network

, Jason Wood School of Computing, University of Leeds, Leeds, LS2 9JT, UK Abstract This paper presents- oriented architecture: the modules simply become services. Charters (Charters et al, 2004; Charters, 2006

Brodlie, Ken

305

Towards a Portable Marxist Criticism: A Critique and Suggestion.  

ERIC Educational Resources Information Center

Reviews the recent work of Terry Eagleton and Raymond Williams, two proponents of Marxist literary theory. Considers the strengths and weaknesses of each writer, outlining an approach to Marxist literary criticism that blends the two theories. (JT)

Pfeil, Fred

1980-01-01

306

Monitoring Butterfly Abundance: Beyond Pollard Walks Jero^ me Pellet1,2  

E-print Network

Monitoring Butterfly Abundance: Beyond Pollard Walks Je´ro^ me Pellet1,2 *, Jason T. Bried3 , David to the characteristics of the species under scrutiny and resources availability. Citation: Pellet J, Bried JT, Parietti D

Richner, Heinz

307

Exploration of Home Economics Related Occupations in Clothing  

ERIC Educational Resources Information Center

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)

Thomas, Virginia F.; Plumb, Sandra

1976-01-01

308

Fluid Dynamics Research 33 (2003) 173189 The distortion of weak fronts by mesoscale orography  

E-print Network

University of Technology, Delft, NL c Environment Centre, University of Leeds, Leeds LS2 9JT, UK d Department (from oros Corresponding author. 0169-5983/03/$30.00 c 2003 Published by The Japan Society of Fluid

Hunt, Julian

309

Nurses and Aides  

ERIC Educational Resources Information Center

Gerontological nursing (the care of the elderly) as a specialization for registered nurses, licensed practical nurses, and nursing aides is discussed with respect to training and qualifications, employment outlook, and earnings for each group. (JT)

Franklin, John

1976-01-01

310

Gingivostomatitis  

MedlinePLUS

... children. It may occur after infection with the herpes simplex virus type 1 (HSV-1), which also causes ... Schiffer JT, Corey L. Herpes simplex virus. In: Mandell GL, Bennett ... of Infectious Diseases . 7th ed. Philadelphia, Pa: Elsevier ...

311

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

ERIC Educational Resources Information Center

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)

Moran, Robert D.

1974-01-01

312

Flight effects of fan noise  

NASA Technical Reports Server (NTRS)

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.

Chestnutt, D. (editor)

1982-01-01

313

End-To-End Interim Report, Phase 4.  

National Technical Information Service (NTIS)

The Joint Advanced Distributed Simulation (JADS) Joint Test and Evaluation (JT&E) was chartered by the Deputy Director, Test Systems Engineering, and Evaluation (Test and Evaluation), Office of the Under Secretary of Defense (Acquisition and Technology) i...

P. M. Hovey, G. J. Marchand

1999-01-01

314

Junction temperature measurement of light emitting diode by electroluminescence.  

PubMed

Junction temperature (JT) is a key parameter of the performance and lifetime of light emitting diodes (LEDs). In this paper, a mobile instrument system has been developed for the non-contact measurement of JTs of LED under LabVIEW control. The electroluminescence (EL) peak shift of the LED is explored to measure the JT. Commercially available high power blue LEDs are measured. A linear relation between emission peak shift and JT is found. The accuracy of the JT is about 1 °C determined by the precision of the emission peak shift, ±0.03 nm, at 3? standard deviation for blue LED. Using this system, on-line temperature rise curves of LED lamps are determined. PMID:22225193

He, S M; Luo, X D; Zhang, B; Fu, L; Cheng, L W; Wang, J B; Lu, W

2011-12-01

315

Density functional theory for the study of the multimode Jahn-Teller effect.  

PubMed

The Jahn-Teller (JT) theorem states that in a molecule with a degenerate electronic state, a structural distortion must occur that lowers the symmetry, removes the degeneracy and lowers the energy. The multideterminental-DFT method performed to calculate the JT parameters for JT active molecules is described. Within the harmonic approximation the JT distortion can be analyzed as a linear combination of all totally symmetric normal modes in any of the low symmetry minimum energy conformation, which allows the intrinsic distortion path (IDP) to be calculated, exactly from the high symmetry point to the low symmetry configuration. Results obtained by the approach described here give direct insight into the coupling of electronic structure and nuclear movements. PMID:21140911

Zlatar, Matija; Gruden-Pavlovi?, Maja; Schläpfer, Carl-Wilhelm; Daul, Claude

2010-01-01

316

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-print Network

-driven start-up by ECH (CDX-U scenario), (2) RF ionization + PF induction (JT-60U scenario), and (3) merging magnetic configurations with varying degrees of curvature. Based on previous experiments on CDX-U, DIII

Princeton Plasma Physics Laboratory

317

Course in Art and the Law  

ERIC Educational Resources Information Center

Justifies and describes a course offered at Stanford Law School in 1972 listing course objectives and outlining content which included focus on art looting, government and the arts, artist's rights in the work of art, consumer protection, and taxation. (JT)

Merryman, John Henry

1974-01-01

318

Geophys. J. Int. (2007) 170, 11651179 doi: 10.1111/j.1365-246X.2007.03415.x GJISeismology  

E-print Network

, UK 2School of Earth and the Environment, Environment Building, University of Leeds, Leeds, LS2 9JT is relatively good (e.g. California, Tibet and Turkey) and most analysis techniques (stacking, small baseline

Biggs, Juliet

319

Consumer-Homemaking for Teenage Parents  

ERIC Educational Resources Information Center

Describes a successful Jefferson County, Georgia, pilot program for teenage parents. The program for male and female high school students includes a counseling component and curriculum focus on prenatal-postnatal care, child care and development, and health services. (JT)

Webb, Jackie Roger; Edenfield, Myrtice

1977-01-01

320

Wooster, J.K., J.G. Venditti, J.T. Minear, Y. Cui, S. Dusterhoff, R. Humphries, P. Nelson, W. Dietrich, L. Sklar (2006), Investigations of Sediment Pulse Morphodynamics in a Flume with Fixed Bars, Eos Trans. AGU, 87(52), Fall Meet.  

E-print Network

of anthropogenically introduced sediment to a river system (i.e., through dam removal or gravel augmentation) requires designed to model sediment release from a dam removal. The volume of the small pulses was approximately was designed to replicate conditions typical of those downstream of dams where upstream sediment supply has

Venditti, Jeremy G.

321

Please cite this article in press as: Birkholzer, J.T., et al., Brine flow up a well caused by pressure perturbation from geologic carbon sequestration: Static and dynamic evaluations. Int. J. Greenhouse Gas Control (2011), doi:10.1016/j.ijggc.2011.01.003  

E-print Network

by pressure perturbation from geologic carbon sequestration: Static and dynamic evaluations. Int. J.elsevier.com/locate/ijggc Brine flow up a well caused by pressure perturbation from geologic carbon sequestration: Static carbon sequestration (GCS) has drawn increasing con- sideration as a promising method to mitigate

Zhou, Quanlin

322

Applicability of the Joule-Thomson Cryocooler Coupled with Membrane-Based Purification System for Liquefaction of Natural Gas in Small Quantities  

Microsoft Academic Search

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

A. Piotrowska; M. Chorowski

2008-01-01

323

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

SciTech Connect

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.

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

324

Optimization of the working fluid in a Joule–Thomson cold stage  

Microsoft Academic Search

Vibration-free miniature Joule–Thomson (JT) coolers are of interest for cooling a wide variety of devices, including low-noise amplifiers, semiconducting and superconducting electronics, and small optical detectors used in space applications. For cooling such devices, coolers are needed which have operating temperatures within a wide temperature range of 2–250K. In this paper, the optimization of the working fluid in JT cold

J. H. Derking; H. J. M. ter Brake; A. Sirbi; M. Linder; H. Rogalla

2009-01-01

325

Crossover Dynamics with Low Energy Excitations in Jahn–Teller Co Perovskites  

Microsoft Academic Search

La1 - xSrxCoO3 serves as a prototype for studying crossover characteristics from static to dynamic lattice effects associated with Jahn–Teller (JT) excitations. With the use of the pair density function analysis as a function of carrier density, evidence for localized lattice distortions associated with a JT active mode is provided. Energy resolved measurements of the dynamic structure factor show that

D. Louca

2002-01-01

326

The high temperature Jahn-Teller transition in LaMn7O12  

Microsoft Academic Search

A first order structural Jahn-Teller transition at T_{JT} = 650 K has been recently reported for the quadruple perovskite LaMn7O12 . We have carried out magnetization and transport measurements below and above T_{JT} in order to investigate the effect of the transition. Electrical conduction turns out to be polaronic, changing from non-adiabatic to adiabatic through the transition. Magnetic behavior can

R. Cabassi; F. Bolzoni; E. Gilioli; F. Bissoli; A. Prodi; A. Gauzzi

2009-01-01

327

Double Degeneracy and Jahn-Teller Effects in CMR Perovskites  

Microsoft Academic Search

Jahn-Teller (JT) electron-phonon coupling effects in the colossal magnetoresistance perovskite compounds La_1-xA_xMnO3 are investigated. Electron-electron correlations between two degenerate Mn eg orbitals are studied in the Gutzwiller approximation. The static JT distortion and antiadiabatic polaron effects are studied in a modified Lang-Firsov approximation. We find that (i) the electron or hole character of the charge carrier depends on the static

Jun Zang; Alan R. Bishop; Heinrich Röder

1996-01-01

328

Intermediate spin state of Co3+ and Co4+ ions in La0.5Ba0.5CoO3 evidenced by Jahn-Teller distortions  

Microsoft Academic Search

From high resolution neutron and synchrotron powder diffraction studies performed on the ideal cubic perovskite compound La0.5Ba0.5CoO3, we have observed the onset of a long-range tetragonal phase accompanying a para-ferromagnetic transition at TC~180 K. The lowering of the crystal symmetry is the direct signature of a cooperative and static Jahn-Teller (JT) distortion of the CoO6 octahedra. The JT effect is

F. Fauth; E. Suard; V. Caignaert

2002-01-01

329

Cooperative Dynamic Jahn-Teller Effect. II. Crystal Distortion in Perovskites  

Microsoft Academic Search

A molecular-field-type theory is given for the second-order phase transitions occurring in perovskite crystals, in which a Jahn-Teller (JT) ion (Mn3+, Cu2+, Cr2+) occupies an octahedral B site. The dynamic character of the JT effect is taken into account and excited vibronic states are included. The ordered system consists of two sublattices, each having the same tetragonal, but opposite orthorhombic,

B. Halperin; R. Englman

1971-01-01

330

Jahn-Teller effect under pressure  

Microsoft Academic Search

This work deals with structural correlation studies in Jahn–Teller (JT) systems of Cu and Mn in the layer perovskites A2CuCl4 and AMnF4. The aim is to explore the influence of the JT effect on the materials' properties as well as its variation with pressure. We present structural studies carried out in the layer perovskites AMnF4 by optical spectroscopy under pressure

F. Aguado; F. Rodríguez

2006-01-01

331

Jahn–Teller Systems at High Pressure  

Microsoft Academic Search

\\u000a Structural studies of Jahn–JT) systems involving transition metal ions often require using complementary spectroscopic techniques\\u000a in order to complete an adequate characterization. x-ray absorption and diffraction though standard techniques for structural\\u000a studies in concentrated materials are not well suited to investigate diluted or structurally subtle JT compounds. In this\\u000a work we analyze the usefulness of optical spectroscopy to investigate structural

Fernando Rodriguez

2010-01-01

332

Properties of Gas Mixtures and Their Use in Mixed-Refrigerant Joule-Thomson Refrigerators  

NASA Astrophysics Data System (ADS)

The Joule-Thomson (J-T) effect has been widely used for achieving low temperatures. In the past few years, much progress has been made in better understanding the working mechanism of the refrigeration method and in developing prototypes for different applications. In this talk, there are three aspects of our research work to be discussed. First, some special thermal properties of the mixtures for achieving liquid nitrogen temperature range will be presented. Secondly, some important conclusions from the optimization of various mixed-refrigerant J-T cycles such as a simple J-T cycle and an auto-cascade mixed-refrigerant J-T cycle will be presented. Moreover, an auto-cascade, mixed-refrigerant J-T refrigerator with a special mixture capable of achieving about 50K will be mentioned. Finally, various prototypes based on the mixed-refrigerant refrigeration technology will be described. These applications include miniature J-T cryocoolers for cooling infrared detectors and high-temperature superconducting devices, cryosurgical knife for medical treatment, low-temperature refrigerators for biological storage and so forth. The on-going research work and unanswered questions for this technology will be also discussed.

Luo, E.; Gong, M.; Wu, J.; Zhou, Y.

2004-06-01

333

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

NASA Astrophysics Data System (ADS)

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 (?_3 and ?_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 ?_3 and ?_4 and possible bilinear coupling between the totally symmetric stretch, ?_1, and ?_4. We conclude that the JT coupling in ?_4 is quite weak. Satisfactory spectral fits can be obtained assuming weak JT coupling for ?_3 also, though there is some evidence of strong JT coupling for ?_3 and the strengths and weaknesses of each case are discussed. Codd, T. et al. 67^{th} Int. Symp. Molec. Spec. (2012)}

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

2013-06-01

334

Performance of a TiN-coated monolithic silicon pin-diode array under mechanical stress  

E-print Network

The Karlsruhe Tritium Neutrino Experiment (KATRIN) will detect tritium beta- decay electrons that pass through its electromagnetic spectrometer with a highly- segmented monolithic silicon pin-diode focal-plane detector (FPD). This pin-diode array will be on a single piece of 500-{\\mu}m-thick silicon, with contact between titanium nitride (TiN) coated detector pixels and front-end electronics made by spring-loaded pogo pins. The pogo pins will exert a total force of up to 50N on the detector, deforming it and resulting in mechanical stress up to 50 MPa in the silicon bulk. We have evaluated a prototype pin-diode array with a pogo-pin connection scheme similar to the KATRIN FPD. We find that pogo pins make good electrical contact to TiN and observe no effects on detector resolution or reverse-bias leakage current which can be attributed to mechanical stress.

B. A. VanDevender; L. I. Bodine; A. W. Myers; J. F. Amsbaugh; M. A. Howe; M. L. Leber; R. G. H. Robertson; K. Tolich; T. D. Van Wechel; B. L. Wall

2012-02-01

335

The challenge of self-governance in complex, globalizing economies: Collection of revised papers of a PhD seminar  

Microsoft Academic Search

Table of Contents: Floriane Clement: A Multi-Scale Analysis of Institutions, Interestsand Beliefs Associated With Forest Policies. Insights from NorthernVietnam; Katrin Daedlow, Robert Arlinghaus, Volker Beckmann: Collective Choice on Different Spatial Levels and over Time: A Framework to Analyze Adaptation and Sustainability of Common Pool Resource Management in German Recreational Fisheries (GRF); Eva Ebenhöh: Designing Agent-Based Models of Water Management Regimes

Elinor Ostrom; Achim Schlüter

2007-01-01

336

Experimental study of a mixed refrigerant Joule-Thomson cryocooler using a commercial air-conditioning scroll compressor  

NASA Astrophysics Data System (ADS)

Mixed refrigerant Joule-Thomson (MR J-T) cryocoolers have been used to create cryogenic temperatures and are simple, efficient, cheap, and durable. However, compressors for MR J-T cryocoolers still require optimization. As the MR J-T cryocooler uses a commercial scroll compressor developed for air-conditioning systems, compressor overheating due to the use of less optimized refrigerants may not be negligible, and could cause compressor malfunction due to burn-out of scroll tip seals. Therefore, in the present study, the authors propose procedures to optimize compressor operation to avoid the overheating issue when the MR J-T cryocooler is used with a commercial oil lubricated scroll compressor, and the present experimental results obtained for a MR J-T cryocooler. A single stage 1.49 kW (2 HP) scroll compressor designed for R22 utilizing a mixture of nitrogen and hydrocarbons was used in the present study. As was expected, compressor overheating and irreversible high temperatures at a compressor discharge port were found at the beginning of compressor operation, which is critical, and hence, the authors used a water injection cooling system for the compressor to alleviate temperature overshooting. In addition, a portion of refrigerant in the high-pressure stream was by-passed into the compressor suction port. This allowed an adequate compression ratio, prevented excessive temperature increases at the compressor discharge, and eventually enabled the MR J-T cryocooler to operate stably at 121 K. The study shows that commercial oil lubricated scroll compressors can be used for MR J-T cryocooling systems if care is exercised to avoid compressor overheating.

Lee, Jisung; Lee, Kyungsoo; Jeong, Sangkwon

2013-05-01

337

Pressure effects on Jahn-Teller distortion in perovskites: The roles of local and bulk compressibilities  

NASA Astrophysics Data System (ADS)

The interplay between the Jahn-Teller (JT) effect and octahedron tilting in transition-metal perovskites is investigated as a function of pressure. Our focus is on its effects on the exchange and electron-phonon interactions, both having a strong influence on materials properties. We demonstrate that the JT distortion in Cu2+ and Mn3+ is reduced upon compression and is eventually suppressed at pressures above 20 GPa. X-ray diffraction and x-ray absorption measurements in A2CuCl4 layer perovskites (A: Rb, CnH2n+1NH3; n=1-3) show that, although pressure slightly reduces the long Cu-Cl distance in comparison to the Cu-Cu distance in the layer, the JT distortion is stable in the 0-20 GPa range. The difference between lattice (?0C=0.14 GPa-1) and local CuCl6 (?0=0.016 GPa-1) compressibilities, together with the high stability of the JT distortion, lead to CuCl6 tilts upon compression. The evolution of the elongated CuCl6 octahedron in A2CuCl4, as well as MnF6 in CsMnF4 and MnO6 in LaMnO3 and DyMnO3, toward a nearly regular octahedron takes place above 20 GPa, in agreement with experimental results and a model analysis based on the JT energy derived from optical absorption spectroscopy: EJT=0.25-0.45 eV/Cu2+, EJT=0.45 eV/Mn3+ (CsMnF4), and EJT=0.25 eV/Mn3+ (LaMnO3). The proposed model clarifies controversial results about pressure-induced JT quenching in Cu2+ and Mn3+ systems, providing an efficient complementary means to predict pressure behavior in perovskites containing JT transition-metal ions.

Aguado, Fernando; Rodríguez, Fernando; Valiente, Rafael; Itiè, Jean-Paul; Hanfland, Michael

2012-03-01

338

Natural Orbital Analysis of Ultrafast Multielectron Dynamics of Molecules  

NASA Astrophysics Data System (ADS)

The ionization dynamics of molecules in intense laser fields is investigated by using a time-dependent multiconfiguration theory for propagating the many-electron wave function in a grid space. We use the natural orbitals obtained from the many-electron wave function, i.e., the molecular orbitals obtained by diagonalizing the one-particle electron density matrix, to analyze the ionization process. We eliminate the ionizing portions of orbitals reaching the grid boundaries set far away from the nuclei; the occupation numbers of natural orbitals decrease due to ionization. The ionization probabilities of individual natural orbitals can be obtained from the accumulated reductions in occupation numbers. We also propose a new definition of molecular orbital energy in order to investigate the energetics of natural orbitals. It is shown that when energies are assigned to natural orbitals {{? }j(t)} as chemical potentials {bar{{? }}j(t)}, one can quantify a correction to the total electronic energy that represents electron correlation; that is, time-dependent correlation energy is introduced. Our attempt is illustrated by numerical results on the time-dependence of the spatial density and chemical potential for a H2 molecule interacting with an intense, near-infrared laser field. We compared the energy ? j (t) supplied by the applied field with the net energy gain ? bar{{? }}j(t) in the chemical potential for ? j (t) and found that energy accepting orbitals of ? bar{{? }}j(t) > {? }j(t) exhibit high ionization efficiency.

Kono, Hirohiko; Oyamada, Takayuki; Kato, Tsuyoshi; Koseki, Shiro

339

Jahn-Teller assisted polaron hopping and associated dielectric response of PrFe0.5Mn0.5O2.95  

NASA Astrophysics Data System (ADS)

The canted G-type antiferromagnet PrFe0.5Mn0.5O2.95 shows an enhanced Jahn-Teller (JT) distortion below 150 K (T*). The resistivity of the grains can be described by variable range hopping between the localized states, and there is a dominant grain boundary contribution to dc resistivity, below T*. Above T*, the total dc resistivity follows small polaron hopping (SPH) conduction. A giant dielectric response is observed, and it can be ascribed to Maxwell-Wagner polarization and SPH mechanism. Despite the low concentration of JT active Mn3+ ions, our result indicates an important role of JT effect on physical properties of PrFe0.5Mn0.5O2.95.

Ganeshraj, C.; Kavita, S.; Mahendiran, R.; Sharma, Neetika; Das, A.; Santhosh, P. N.

2013-09-01

340

Jahn-Teller spin polarons in perovskite cobaltites  

NASA Astrophysics Data System (ADS)

The interplay of the electron transfer integral and lattice elastic energy in A1-xAx'CoO3 is investigated by neutron diffraction and the pair density function analysis. By effectively widening the bandwidth with Ca, Sr, and Ba substitutions at the A site, evidence for the stability of the intermediate-spin (IS) configuration through the formation of static local Jahn-Teller (JT) distortions is provided. When the critical radius exceeds ˜1.22Å , spin activated JT polarons are formed in the absence of long-range magnetic ordering. JT polarons are prevalent in crystals with Sr and Ba but not in those with Ca. In the metallic and magnetically ordered phase, the static signature of the distortions is absent, suggesting that the IS state may be dynamically shared between Co3+ and Co4+ ions.

Phelan, D.; Yu, J.; Louca, Despina

2008-09-01

341

Potential improvements in turbofan engine fuel economy  

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

342

Evidence for a Jahn-Teller distortion in the CMR layered manganite La{sub 1.4}Sr{sub 1.6}Mn{sub 2}O{sub 7}  

SciTech Connect

The changes with temperature in the crystallographic structure of the two-layered La{sub 1.4}Sr{sub 1.6}Mn{sub 2}O{sub 7}, are on average quite small but the atomic pair density function analysis of pulsed neutron diffraction data shows that the lattice is locally distorted in accordance with the change in the transport properties. In particular, while no Jahn-Teller (JT) distortion is expected in the layered compounds because the octahedral bilayers are almost cubic, lattice distortions attributed to a large JT effect are present and are of comparable magnitude as in the cubic perovskite system. This could in turn explain the similarity in their properties. The number of the JT distorted sites is reduced with temperature concomitantly with the decrease in resistivity of the ab-plane.

Louca, D.; Kwei, G.H. [Los Alamos National Lab., NM (United States); Mitchell, J.F. [Argonne National Lab., IL (United States)

1998-12-31

343

Direct Observation of the High Magnetic Field Effect on the Jahn-Teller State in TbVO4  

SciTech Connect

We report the first direct observation of the influence of high magnetic fields on the Jahn-Teller (JT) transition in TbVO{sub 4}. Contrary to spectroscopic and magnetic methods, x-ray diffraction directly measures the JT distortion; the splitting between the (311)/(131) and (202)/(022) pairs of Bragg reflections is proportional to the order parameter. Our experimental results are compared to mean-field calculations, taking into account all possible orientations of the grains relative to the applied field, and qualitative agreement is obtained.

Detlefs, C.; Duc, F.; Kazei, Z.; Vanacken, J.; Frings, P.; Bras, W.; Lorenzo, J.; Canfield, P.; Rikken, G.

2008-02-08

344

Energy Consumption and Demand as Affected by Heat Pumps that Cool, Heat and Heat Domestic Water  

E-print Network

_tn....:.0'.....::J\\'t~ llltlOO :.' ..~ I~"" UUNf; ",Ill. ~ I''''~'''' ? .... 1I1i';> ......t.til~tI .~, ... - ... "dIu ,.. .. 1Ib1~~ ,,~ _II"." .. ;Ill> '''''''.1 Ilt"~'.. Ilt~?, ? .'1 "....... .00 ~... IIi. t. ....... I'iW'" t, J..._tn....:.0'.....::J\\'t~ llltlOO :.' ..~ I~"" UUNf; ",Ill. ~ I''''~'''' ? .... 1I1i';> ......t.til~tI .~, ... - ... "dIu ,.. .. 1Ib1~~ ,,~ _II"." .. ;Ill> '''''''.1 Ilt"~'.. Ilt~?, ? .'1 "....... .00 ~... IIi. t. ....... I'iW'" t, J...

Cawley, R.

345

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

SciTech Connect

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.

Proffen, Thomas [Los Alamos National Laboratory; Sundaram, Nalini [UCSC; Jiang, Y [UCSC; Anderson, Ingrid [UCSC; Belanger, D P [UCSC; Booth, C H [LBNL; Bridges, F [UCSC; Mitchell, J F [ANL; Zheng, H [ANL

2008-01-01

346

Natural Gas Purchasing Options  

E-print Network

13-15, 1988 ESL-IE-88-09-04 Proceedings from the Tenth Annual Industrial Energy Technology Conference, Houston, TX, September 13-15, 1988 Panel Moderator Joel S. Gilbert Dimes and Moore Panel MelJt)ers Steve Bi.achoff Arizona Public service... 13-15, 1988 ESL-IE-88-09-04 Proceedings from the Tenth Annual Industrial Energy Technology Conference, Houston, TX, September 13-15, 1988 Panel Moderator Joel S. Gilbert Dimes and Moore Panel MelJt)ers Steve Bi.achoff Arizona Public service...

Watkins, G.

347

MSU Extension Publication Archive Archive copy of publication, do not use for current recommendations. Up-to-date  

E-print Network

. Freezing Green and Yellow Beans Michigan State University Extension Service Judy VanWesten, Expanded Food;C.-t=:z..INGr IS THE EA"5\\E5T ANt:> SAFEsr WA'l \\C:) t>"RESER\\JE: FOoD. HOWe-VE"1f=RE:e'"Z.' tvc;, ONL" s~N ~tJt:)s PrtJD EQlJ IPM.E'tJT TO ke;E'P 'FOOD AS FREE PROM BACTE'RlA As PO~S\\6LE". FoLLOW Dl

348

Enhancement of the Jahn-Teller distortion by magnetization in manganites  

NASA Astrophysics Data System (ADS)

Using measurements of resonant x-ray scattering from a LaMnO3/SrMnO3 superlattice grown on SrTiO3(001), we present experimental evidence for the enhancement of the Jahn-Teller distortion by magnetic ordering in manganites. With a specially tuned periodicity of the superlattice, scattering due to the Jahn-Teller (JT) distortion is separated from charge and magnetic scattering. The measured JT distortion is markedly enhanced upon the emergence of magnetization and strongly correlated with the spin ordering in the superlattice. Such strong correlation reveals the nature of electron-electron interaction for orbital ordering in manganites.

Chu, Y. Y.; Wu, H. H.; Liu, S. C.; Lin, Hsiu-Hau; Matsuno, J.; Takagi, H.; Huang, J. H.; van den Brink, J.; Chen, C. T.; Huang, D. J.

2012-03-01

349

The ascorbic acid content of stem rust susceptible and resistant wheat  

E-print Network

wheats by growth stages. Abbreviations: SDL - seedling stage TLR - tillering stage JT - joint BT - boot FL - flowering SD ? soft dough HD ~ hard dough HP - ripe hp were inoculated with race 15b of stem rust. Hard Federation, Nugget, Wisconsin... - flowering TLR - tillering stage SF ~ soft dough JT - joint HD ~ hard dough BT - boot RP - ripe M G S. OF AS C O R BI C AC ID PE R 10 0 GMS . FR ESH W G T h, Figure 4* Ascorbic acid content of four wheats by growth stages...

Pilgrim, Arthur James

2013-10-04

350

Quantum stochastic processes for maps on Hilbert C*-modules  

NASA Astrophysics Data System (ADS)

We discuss pairs (?, ?) of maps, where ? is a map between C*-algebras and ? is a ?-module map between Hilbert C*-modules, which are generalization of representations of Hilbert C*-modules. A covariant version of Stinespring's theorem for such a pair (?, ?) is established, and quantum stochastic processes constructed from pairs ({?t}, {?t}) of families of such maps are studied. We prove that the quantum stochastic process J = {Jt} constructed from a ?-quantum dynamical semigroup ? = {?t} is a j-map for the quantum stochastic process j = {jt} constructed from the given quantum dynamical semigroup ? = {?t}, and that J is covariant if the ?-quantum dynamical semigroup ? is covariant.

Heo, Jaeseong; Ji, Un Cig

2011-05-01

351

Vortex proliferation in the Berezinskii-Kosterlitz-Thouless regime on a two-dimensional lattice of Bose-Einstein condensates.  

PubMed

We observe the proliferation of vortices in the Berezinskii-Kosterlitz-Thouless regime on a two-dimensional array of Josephson-coupled Bose-Einstein condensates. As long as the Josephson (tunneling) energy J exceeds the thermal energy T, the array is vortex free. With decreasing J/T, vortices appear in the system in ever greater numbers. We confirm thermal activation as the vortex-formation mechanism and obtain information on the size of bound vortex pairs as J/T is varied. PMID:17678271

Schweikhard, V; Tung, S; Cornell, E A

2007-07-20

352

Treatment of the multimode Jahn-Teller problem in small aromatic radicals.  

PubMed

The family of the Jahn-Teller (JT) active hydrocarbon rings, C(n)H(n) (n = 5-7), was analyzed by the means of multideterminantal density functional theory (DFT) approach. The multimode problem was addressed using the intrinsic distortion path (IDP) method, in which the JT distortion is expressed as a linear combination of all totally symmetric normal modes in the low symmetry minimum energy conformation. Partitioning of the stabilization energy into the various physically meaningful terms arising from Kohn-Sham DFT has been performed to get further chemical insight into the coupling of the nuclear movements and the electron distribution. PMID:21875069

Gruden-Pavlovi?, Maja; García-Fernández, Pablo; Andjelkovi?, Ljubica; Daul, Claude; Zlatar, Matija

2011-10-01

353

Double Degeneracy and Jahn-Teller Effects in CMR Perovskites  

Microsoft Academic Search

Jahn-Teller (JT) electron-phonon coupling effects in the colossal\\u000amagnetoresistance perovskite compounds $La_{1-x}A_xMnO_3$ are investigated.\\u000aElectron-electron correlations between two degenerate Mn $e_g$ orbitals are\\u000astudied in the Gutzwiller approximation. The static JT distortion and\\u000aantiadiabatic polaron effects are studied in a modified Lang-Firsov\\u000aapproximation. We find that (i) the electron or hole character of the charge\\u000acarrier depends on the static

Jun Zang; A. R. Bishop; H. Roder

1995-01-01

354

The local Jahn-Teller effect in (La/Sr){sub n+1}Mn{sub n}O{sub 3n+1}  

SciTech Connect

Lattice polarons form an important constituent in the mechanism of magnetism and transport of the (La/Sr){sub n+1}Mn{sub n}O{sub 3n+1} (for n = 2 and {infinity}) colossal magnetoresistance manganites. The coupling of the polaronic distortions to the local Jahn-Teller (JT) effect has been characterized by the pulsed neutron pair density function (PDF) analysis. Distortions of equal magnitude to the ones found in perovskites arising from a JT effect are found in the 2-dimensional layer crystals. The coupling of the distortions to the lattice is similar in both systems suggesting that lattice polarons are formed independently to the crystal dimensionality.

Louca, D.; Kwei, G.H. [Los Alamos National Lab., NM (United States); Egami, T. [Univ. of Pennsylvania, Philadelphia, PA (United States)

1998-12-31

355

Production of 5,8,11-eicosatrienoic acid by a ?5 and ?6 desaturation activity-enhanced mutant derived from a ?12 desaturation activity-defective mutant of Mortierella alpina 1S-4  

Microsoft Academic Search

Enhanced production of 5,8,11-eicosatrienoic acid (Mead acid, 20:3̩) was attained with a mutant fungus, Mortierella alpina JT-180, derived from ྫྷ desaturation activity-defective and Ɩ desaturation activity-enhanced M. alpina M209-7. Production of 20:3̩ by JT-180 was 1.4 times greater than that of the parent strain M209-7. This is thought to be due to its enhanced ƕ desaturation activity, which was 3.3

E. Sakuradani; N. Kamada; Y. Hirano; M. Nishihara; H. Kawashima; K. Akimoto; K. Higashiyama; J. Ogawa; S. Shimizu

2002-01-01

356

Signatures of extra dimensional sterile neutrinos  

NASA Astrophysics Data System (ADS)

We study a large extra dimension model with active and sterile Dirac neutrinos. The sterile neutrino masses stem from compactification of an extra dimension with radius R and are chosen to have masses around eV or keV, in order to explain short-baseline anomalies or act as warm dark matter candidates. We study the effect of the sterile neutrino Kaluza-Klein tower in short-baseline oscillation experiments and in the beta spectrum as measurable by KATRIN-like experiments.

Rodejohann, Werner; Zhang, He

2014-10-01

357

Bolometers in magnetic field: Use of NTD Ge sensors  

NASA Astrophysics Data System (ADS)

In this paper we report about the properties of Neutron Transmutation Doped (NTD) Ge in magnetic fields, focusing on the electrical conduction properties and magnetoresistance, in view of a use as sensors for bolometers in magnetic field. Samples of two different doping density were studied in magnetic field up to 5 T and temperature down to 65 mK. NTD sensors show a reproducible gigantic magnetoresistance that leads to an enhancement of their sensitivity to temperature variations. We discuss preliminarily the possible use of NTD sensors in magnetic field in particle detector developments, in particular for the KATRIN experiment.

Pasca, E.; Barucci, M.; Giuliani, A.; Olivieri, E.; Risegari, L.; Ventura, G.

2007-06-01

358

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research  

E-print Network

-Blanco , S. Shaw, P. Bots, T. Roncal-Herrero, L.G. Benning School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom a r t i c l e i n f o Article history: Received 23 June 2011 and electron microscopy. The experiments showed that Mg increased the stability of ACC and favoured

Benning, Liane G.

359

Multilevel path simulation for jump-diffusion Yuan Xia, Michael B. Giles  

E-print Network

term J(t) is a compound Poisson process N(t) i=1 (Yi - 1), the jump magnitude Yi has a prescribed distribution, and N(t) is a Poisson process with in- tensity , independent of the Brownian motion. Due with twice as many timesteps. If the Poisson jump rate is constant, the jump times are the same on both paths

Giles, Mike

360

Production of Artificial Lightning in An Ordinary Clear Light Bulb.  

ERIC Educational Resources Information Center

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)

Zaffo, Peter Alfred

1981-01-01

361

A, Sciencg %Wide, Feature Re'len.sad upon receipt  

E-print Network

&&JT Toward the cloee of the nineteonth cmtiii-y R plant of the pea f m i l y , known botanically as Abrus is somotirnoe called the 'Ipatarnoster Pea," on accmt of tho use of its poisonous seeds i n malcing roearies and branches of t h i s plant n variety of mundane events, including not only storms and weather changes

362

Integration host factor is required for replication of pYGK-derived plasmids in Aggregatibacter actinomycetemcomitans.  

PubMed

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 ?- or ?- 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 IHF?-IHF? 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

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

2014-08-01

363

I Learn You: Accountability at the Academy  

ERIC Educational Resources Information Center

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)

Dennis, Lawrence J.

1975-01-01

364

Performance of a MEMS Heat Exchanger for a Cryosurgical Probe  

Microsoft Academic Search

This paper presents the experimental test results for two 2 nd generation Micro-Electro- Mechanical Systems (MEMS) heat exchangers that are a composite of silicon plates with micro- machined flow passages interleaved with glass spacers. The MEMS heat exchangers were designed for use as the recuperative heat exchanger within a Joule-Thomson (JT) cycle used to energize a cryosurgical probe. The heat

M. J. White; W. Zhu; G. F. Nellis; S. A. Klein; Y. B. Gianchandani

365

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

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

366

Jumping translocations of 1q12 in multiple myeloma: a novel mechanism for deletion of 17p in cytogenetically defined high-risk disease.  

PubMed

Multiple myeloma (MM) is a B-cell malignancy driven in part by increasing copy number alterations (CNAs) during disease progression. Prognostically significant CNAs accumulate during clonal evolution and include gains of 1q21 and deletions of 17p, among others. Unfortunately, the mechanisms underlying the accumulation of CNAs and resulting subclonal heterogeneity in high-risk MM are poorly understood. To investigate the impact of jumping translocations of 1q12 (JT1q12) on receptor chromosomes (RCs) and subsequent clonal evolution, we analyzed specimens from 86 patients selected for unbalanced 1q12 aberrations by G-banding. Utilizing spectral karyotyping and locus-specific fluorescence in situ hybridization, we identified 10 patients with unexpected focal amplifications of an RC that subsequently translocated as part of a sequential JT1q12 to one or more additional RCs. Four patients exhibited amplification and translocation of 8q24 (MYC), 3 showed amplification of 16q11, and 1 each displayed amplification of 18q21.3 (BCL2), 18q23, or 4p16 (FGFR3). Unexpectedly, in 6 of 14 patients with the combination of the t(4;14) and deletion of 17p, we identified the loss of 17p as resulting from a JT1q12. Here, we provide evidence that the JT1q12 is a mechanism for the simultaneous gain of 1q21 and deletion of 17p in cytogenetically defined high-risk disease. PMID:24497533

Sawyer, Jeffrey R; Tian, Erming; Heuck, Christoph J; Epstein, Joshua; Johann, Donald J; Swanson, Charles M; Lukacs, Janet L; Johnson, Marian; Binz, Regina; Boast, Angela; Sammartino, Gael; Usmani, Saad; Zangari, Maurizio; Waheed, Sarah; van Rhee, Frits; Barlogie, Bart

2014-04-17

367

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

368

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

369

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

370

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

371

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

372

Relativistic Jahn-Teller effects in the photoelectron spectra of tetrahedral P{sub 4}, As{sub 4}, Sb{sub 4}, and Bi{sub 4}  

SciTech Connect

The group-V tetrahedral cluster cations P{sub 4}{sup +}, As{sub 4}{sup +}, Sb{sub 4}{sup +}, and Bi{sub 4}{sup +} are known to exhibit exceptionally strong Jahn-Teller (JT) effects of electrostatic origin in their {sup 2}E ground states and {sup 2}T{sub 2} excited states. It has been predicted that there exist, in addition, JT couplings of relativistic origin (arising from the spin-orbit (SO) operator) in {sup 2}E and {sup 2}T{sub 2} states of tetrahedral systems, which should become relevant for the heavier elements. In the present work, the JT and SO couplings in the group-V tetramer cations have been analyzed with ab initio relativistic electronic structure calculations. The vibronic line spectra and the band shapes of the photoelectron spectra were simulated with time-dependent quantum wave-packet methods. The results provide insight into the interplay of electrostatic and relativistic JT couplings and SO splittings in the complex photoelectron spectra of these systems.

Opalka, Daniel; Domcke, Wolfgang [Department of Chemistry, Technische Universitaet Muenchen, D-85747 Garching (Germany); Poluyanov, Leonid V. [Institute of Chemical Physics, Academy of Sciences, Chernogolovka, Moscow 142432 (Russian Federation)

2011-09-14

373

Quasi-soliton interaction of pursuit-evasion waves in a predator-prey system M. A. Tsyganov  

E-print Network

resulting from random motion of both species. We demonstrate a new type of propagating wave in this system Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK A. V. Holden School of Biomedical, including growth and inter- action of the species, and their undirected spread in space, e.g. resulting from

Biktashev, Vadim N.

374

Quasisoliton interaction of pursuitevasion waves in a predatorprey system M. A. Tsyganov  

E-print Network

resulting from random motion of both species. We demonstrate a new type of propagating wave in this system Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK A. V. Holden School of Biomedical, including growth and inter­ action of the species, and their undirected spread in space, e.g. resulting from

Biktashev, Vadim N.

375

The moment problem and its relation to statistics  

E-print Network

distribution function P(x) such that Llm F?(x) ~ P(x) n~ at each point of continuity of F(x), 17, (0) The m. g. f. 's of F(x) and Fn(x), Q(x) and Qn(x) exist for JtJ c a. (0) Ltm Qn(t) + Q(t) for Jt I c a and uniformly in each interval n~~ JtJ S 5& a. 0...(xc, ~ s As an examJSle, take the ?equence of distribution functions x Fn(x)" m ~ / (e-x + e ) dx n+1 i p Gn(t) ~ JL ? ( eA(e-x ~ e-nx) n+ 1 G(0 1t~t+ "+ t&+ + t&a n(n+1) n nt 1 n n+1) + y tk 1 i'or JtJ c 1 n (n + 1) Now Lim G?(t) ~ 1 + t + t2...

Wood, Sam Madeley

2012-06-07

376

Neurocognitive Modeling Neurocognitive Modeling of Perceptual Decision Making  

E-print Network

.g., Brown & Heathcote, 2008; Busemeyer & Townsend, 1993; Dayan & Daw, 2008; Ratcliff & Rouder, 1998). And weNeurocognitive Modeling 1 Neurocognitive Modeling of Perceptual Decision Making Thomas J, J.T. Townsend, Z.J. Wang, & A. Eidels (Eds.), Oxford Handbook of Computational and Mathematical

Palmeri, Thomas

377

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

ERIC Educational Resources Information Center

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)

Levine, Joanne L.

1975-01-01

378

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

ERIC Educational Resources Information Center

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)

Steinbach, Sheldon Elliot; Reback, Joyce E.

1974-01-01

379

19812001) was indeed the first paper published by the researcher, we only  

E-print Network

2001 |www.nature.com All sectors of society must work together to save biodiversity Sir -- Conservation Rivero Institute of Cell, Animal and Population Biology, University of Edinburgh, Kings Buildings, West Mains Road, Edinburgh EH9 3JT, UK 1. Nature 407, 659 (2000). 2. Ferrer, P. Nature 407, 941 (2000). 3

Rivero, Ana

380

A predicative proof of exponentiation of locally compact formal topologies.  

E-print Network

of relation). Instead the full subcategory of inductively generated formal topologies provides a predicative presentation of open locales (see [JT84]). A predicative study of exponentiation in the context of formalA predicative proof of exponentiation of locally compact formal topologies. Maria Emilia Maietti

Maietti, Maria Emilia

381

J. theor. Biol. (2002) 215, 385397 doi:10.1006/jtbi.2002.2529, available online at http://www.idealibrary.com on  

E-print Network

Science Ltd. All rights reserved. Introduction For all animals, the consumption of food provides the raw AB15 8QH, U.K. w Institute of Cell, Animal and Population Biology, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, U.K. and 8 Animal Nutrition and Health Department, Animal Biology

Alvarez, Nadir

382

Ultrasound in Med. & Bidl. Vol. 8. pp. 207-208 Printed in Great Britain. All rights reserved  

E-print Network

review) only further points out the need for precise pairing of sham and treated groups. Thus, a slightly., are involved. C.A. Cain F. Dunn Bioacoustics Research Lab., University of Illinois, Urbana, Illinois. Immunopathol. 14:18-29. Anderson, D.W. and Barrett, J.T. (1981). Depression of phagocytosis by ultrasound

Illinois at Urbana-Champaign, University of

383

Examination of climate risk using a modified uncertainty matrix framework--Applications in the water sector  

E-print Network

Institute and ESRC Centre for Climate Change Economics and Policy, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK f Climate Change Impacts, Adaptation and Mitigation (CC-IAM) Research climate change could challenge current freshwater management practices (e.g., Wei et al., 2011), and has

Fowler, Hayley

384

1Wood Borer --WB-XX-W America's Least Wanted Wood-Borers  

E-print Network

AMBROSIA BEETLE, ANISANDRUS MAICHE (STARK) Jeffrey D. Holland, K. R. Raje, J.T. Shukle, and V. R. Ferris, Entomologists This ambrosia beetle is native to parts of Asia.Es- tablished populations of these beetles were Islands). Identification: The adult beetles can be differenti- ated from other species Anisandrus

Ginzel, Matthew

385

1Wood Borer --WB-XX-W America's Least Wanted Wood-Borers  

E-print Network

AMBROSIA BEETLE, PLATYPUS QUERCIVORUS (MURAYAMA) Jeffrey D. Holland, K. R. Raje, J.T. Shukle, and V. R. Ferris, Entomologists This ambrosia beetle is native to southeast Asia. As the specific name suggests are produced by a pair of adults. Larvae may reach the fifth instar by late R: A female ambrosia beetle (Photo

Ginzel, Matthew

386

1Wood Borer --WB-XX-W America's Least Wanted Wood-Borers  

E-print Network

SHOT BEETLE, CNESTUS MUTILATUS (BLANDFORD) Jeffrey D. Holland, K. R. Raje, J.T. Shukle, and V. R. Ferris, Entomologists This alien bark beetle has been detected in Mississip- pi and Florida. These beetles are known to actively search for their host plants and also have a high reproductive ca- pability

Ginzel, Matthew

387

MULTIGRID METHODS FOR EHL PROBLEMS Elyas Nurgat and Martin Berzins  

E-print Network

contact bearings and cams, this is not the case due to high pressures and this is referred to as Elasto­Hydrodynamic, University of Leeds Leeds, LS2 9JT, UK INTRODUCTION In many bearings and contacts, forces are transmitted the entire load, then we have hydrodynamic lubrication, where the lubricant film is determined by the motion

388

Drift of large-core spiral waves in inhomogeneous excitable media  

E-print Network

erential equations. Description of the dynamics of spiral waves or there 3D analogues, scroll waves, can system. Current address: School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK c 1998 Kluwer Academic Publishers. Printed in the Netherlands. jbp.tex; 30 12 1998; 18:06; p.1 #12;2 1

Biktashev, Vadim N.

389

Drift of largecore spiral waves in inhomogeneous excitable media  

E-print Network

differential equations. Description of the dynamics of spiral waves or there 3D analogues, scroll waves, can­diffusion system. \\Lambda Current address: School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK c fl 1998 Kluwer Academic Publishers. Printed in the Netherlands. jbp.tex; 30/12/1998; 18:06; p.1 #12

Biktashev, Vadim N.

390

doi: 10.1098/rspb.2010.0772 , 3291-3297 first published online 9 June 20102772010Proc. R. Soc. B  

E-print Network

). Much of our understanding of invertebrate immunity is built on studies of insect­parasite systems, Edinburgh EH9 3JT, UK Linking measures of immune function with infection, and ultimately, host and parasite and timing of a cellular immune response in the crustacean Daphnia magna following exposure to its

Obbard, Darren

391

Non-Formal Education and Rural Development--A Historical Sketch and Selected Case Studies  

ERIC Educational Resources Information Center

Alternative models of education which have succeeded in India are described. They are institutions of non-formal education and rural development with roots in the schooling process of ancient India. The author notes present factors which make India well suited for such systems to function better than the present British-imposed system. (JT)

Tillman, Martin

1976-01-01

392

Financial Aid Reports: Loans to Parents, New Help for the Middle-Income Family  

ERIC Educational Resources Information Center

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)

Bowman, James L.; Johnstone, D. Bruce

1975-01-01

393

Information Granulation for Web based Information Retrieval Support Systems  

E-print Network

Information Granulation for Web based Information Retrieval Support Systems J.T. Yao Y.Y. Yao of Web based information retrieval support systems (IRSS). In particular, we apply clustering methods granulation supports a different user task. Keywords: Information retrieval, Granular computing, Information

Yao, JingTao

394

Summary of current research interests The Cells for Sight team is aiming to understand the biology and  

E-print Network

and clinical techniques for human LESC transplantation. We are also investigating the role of connective tissue an improvement in their clinical condition following cultured limbal epithelial stem cell transplantation by fibroblasts: a role for CTGF in contractile scarring. Am. J. Path. 163 (5): 2043-2052. Daniels, JT, Limb, GA

Saunders, Mark

395

Vol. 138, No. 1, 1986 BlOCHEMlCAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS July 16, 1986 Pages 146-152  

E-print Network

* Department of Plant Sciences and *Department of Biochemistry University of Leeds, Leeds LS2 9JT, England-II, light-harvesting chlorophyll a/b pigment-protein complex;-- PS, photosystem. 0006-291X/86 $1.50 Copyrt

Allen, John F.

396

4, 37213783, 2004 Systematic reduction  

E-print Network

. Pilling2 1 Energy and Resources Research Institute, University of Leeds, Leeds LS2 9JT, United Kingdom 2 concentration sensitivity analysis and overall rate sensitivity anal- ysis proved to be efficient and capable to reproduce the concentration profiles of the important species selected from the full mechanism over a wide

Boyer, Edmond

397

3, 60296061, 2003 Validation of the  

E-print Network

, and M. J. Pilling1 1 Department of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK 2 2003 Abstract An assessment of the accuracy of OH concentrations measured in a smog chamber photolysis/ozone actinometry approach. OH concentrations were inferred from the instantaneous rate of removal

Paris-Sud XI, Université de

398

Atmos. Chem. Phys., 4, 20572081, 2004 www.atmos-chem-phys.org/acp/4/2057/  

E-print Network

. Pilling2 1Energy and Resources Research Institute, University of Leeds, Leeds LS2 9JT, UK 2School ways in which their concentration levels can be controlled through the reduction of their precursory such as the Leeds Master Chemi- cal Mechanism (Pilling et al., 1999; Jenkin et al., 1997), are capable

Meskhidze, Nicholas

399

Seasonal characteristics of tropical marine boundary layer air measured at the Cape Verde Atmospheric  

E-print Network

& D. Stone & L. K. Whalley & M. J. Evans & M. J. Pilling & R. J. Leigh & P. S. Monks & A. Karunaharan atmospheric dust concentrations. Fine mode aerosol at the CVAO contains a significant fraction of non-sea salt :M. J. Pilling :S. Vaughan School of Chemistry, University of Leeds, Leeds LS2 9JT, UK T. Ingham :L

400

4, 56835731, 2004 MCMv3 and MCMv3.1  

E-print Network

, and M. J. Pilling1 1 School of Chemistry, University of Leeds, Leeds LS2 9JT, UK 2 Imperial College in the mechanisms, in particu-10 lar: 1) an over-estimation of the ozone concentration, 2) an under concentrations of ozone have been known for a long time now to have adverse effects on human health

Paris-Sud XI, Université de

401

Provision for Community College Faculty Development in Collective Bargaining Agreements  

ERIC Educational Resources Information Center

Trends of collective negotiations were examined as they affect inservice education, through an examination of collective bargaining agreements. Conclusion: the trend is presently one of negotiation of provisions in a piecemeal fashion rather than one with the goal of establishing comprehensive professional improvement programs. (Editor/JT)

Wallace, Terry H. Smith

1976-01-01

402

Numerical Modeling of Salt Tectonics on Passive Continental Margins: Preliminary Assessment of the Effects of Sediment Loading,  

E-print Network

Numerical Modeling of Salt Tectonics on Passive Continental Margins: Preliminary Assessment Sciences The University of Leeds LS2 9JT Leeds United Kingdom Abstract Salt tectonics in passive model of frictional-plastic sedimentary overburden overlying a linear viscous salt layer. We present

Beaumont, Christopher

403

Salt tectonics driven by differential sediment loading: Stability analysis and finite element experiments  

E-print Network

1 Salt tectonics driven by differential sediment loading: Stability analysis and finite element University of Leeds Leeds LS2 9JT United Kingdom e-mail: lykke@earth.leeds.ac.uk Short running title: Salt salt layer drives salt deformation and has a significant impact on the structural evolution

Beaumont, Christopher

404

Systematic design of gateways between multimedia signalling protocols using supervisors  

E-print Network

and J.-T. Lim Abstract: For the major signalling protocols SIP and H.323 in a multimedia communication communications require the interoperation of communication networks with different protocols. The gateways different protocols. Two popular standards for multimedia signalling are Session Initiation Protocol (SIP

Lim, Jong-Tae

405

Herniation of the temporomandibular joint into the external auditory meatus secondary to benign necrotising otitis externa  

Microsoft Academic Search

The temporomandibular joint (TMJ) is intimately related to the external auditory meatus (EAM). Herniation of the joint into the EAM occurs secondary to neoplasia, trauma, inflammation and developmental problems [Conover GL, Crammond RJ. Tympanic plate fracture from mandibular trauma. J Oral Maxillofac Surg 1985;43:292–4; Ali TS, Rubinstein JT. Rheumatoid arthritis of the temporomandibular joint with herniation into the external auditory

Neil C.-W. Tan; Alan Wilson; Jonathan Buckland

2009-01-01

406

Origin of retrograde fluids in metamorphic rocks B. Yardley*, S. Gleeson, S. Bruce, D. Banks  

E-print Network

of Earth Sciences, University of Leeds, Leeds LS2 9JT, UK Abstract Retrograde alteration of crystalline- ites led to the recognition that, at least in the vicinity of cooling plutons, meteoric water can). Subsequently, research on deep waste disposal and geothermal energy, and scientific deep drilling, have

Banks, David

407

Operational Management of Area Environment.  

ERIC Educational Resources Information Center

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)

Sprague, George W.

408

rspb.royalsocietypublishing.org Cite this article: Seddon N, Botero CA, Tobias  

E-print Network

, MacGregor HEA, Rubenstein DR, Uy JAC, Weir JT, Whittingham LA, Safran RJ. 2013 Sexual selection, Jason T. Weir7, Linda A. Whittingham4 and Rebecca J. Safran8 1 Edward Grey Institute, University mixed results and the mechanisms involved remain unclear. Here, we use a novel phylogenetic approach

Rubenstein, Dustin R.

409

, 20130530, published 2 October 201392013Biol. Lett. Toms Albrecht and Jan T. Lifjeld  

E-print Network

-off between sperm length and integrity Patterns of sperm damage in Chernobyl passerine birds Supplementary JT. 2013 Patterns of sperm damage in Chernobyl passerine birds suggest a trade-off between sperm://rsbl.royalsocietypublishing.org. Evolutionary biology Patterns of sperm damage in Chernobyl passerine birds suggest a trade-off between sperm

Mousseau, Timothy A.

410

How to Profit from Special Orders  

ERIC Educational Resources Information Center

The Blank Check Order System was developed to cut paperwork and in-store processing costs for special order books. The customer pays in advance and the bookstore sends a blank check order to the publisher. The process and its advantages are described in detail including evaluation by publishers and college store managers. (JT)

Ollis, Don

1975-01-01

411

National Education Trust Fund  

ERIC Educational Resources Information Center

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)

Shapp, Milton J.

1975-01-01

412

Homocysteine as a risk factor for CVD mortality in men with other CVD risk factors: the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study  

Microsoft Academic Search

Abstract. Virtanen JK, Voutilainen S, Alfthan G, Korhonen MJ, Rissanen TH, Mursu J, Kaplan GA, Salonen JT (University of Kuopio, Kuopio; National Public Health Institute, Helsinki, Finland; University of Michigan, Ann Arbor, USA; and Oy Jurilab Ltd, Kuopio, Finland). Homocysteine as a risk factor for CVD mortality in men,with other CVD risk factors: the Kuopio Ischaemic,Heart Disease Risk Factor (KIHD)

J. K. V IRTANEN; T. H. R ISSANEN

2005-01-01

413

Hoods for Science Laboratories.  

ERIC Educational Resources Information Center

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)

Horowitz, Harold; and others

414

Thomas, J.R. and Clem, A.W, 1991, PWR moderator temperature coefficient via noise analysis: time series methods, Proceedings of SMORNVI, Gatlinburg, 34.01  

E-print Network

: Neural Network Calibration, Nucl. Technology 107:236 Tou, J.T., and Gonzalez, R.C., 1974, Pattern, Nucl. Technology 56:484. Tylee, J.L., 1983, On­line failure detection in nuclear power plant, Implementation of a model reference adaptive control sys­ tem using neural network to control a fast breeder

Pázsit, Imre

415

Changes in South Asian monsoon: New high-resolution paleoclimaticrecords from Tibet, China  

E-print Network

TANG ~ingyu',SHEN ~aiming',LIU ~ a m b i u ~8.J.T. 0verpeck3 1.Nanjing Institute of Geology, LouisianaState University, Baton Rouge,LA 70803, USA; 3. NOAA Paleoclimatology Program,National GeophysicalData Center, Boulder, CO 80303, USA Abstract High-resolution pollen records from 6 small lakes in the Tibetan

Liu, Kam-biu

416

An investigation of orientational symmetry-breaking mechanisms in high Landau levels  

E-print Network

) LL is occupied, and the 2DES exhibits its most spectacular phenomenon: the fractional quantized Hall rights reserved. PACS: 73.20.Dx; 73.40.Kp; 73.50.Jt Keywords: D. Quantum Hall effect; D. Electronic,3]. The most striking of these signatures is the rapid development, at very low temperatures, of strong

Eisenstein, Jim

417

Contributed Paper Using Changes in Agricultural Utility to Quantify  

E-print Network

, Nelson Mandela Metropolitan University, Port Elizabeth 6031, Eastern Cape, South Africa School of Geography, University of Leeds, Leeds, LS2 9JT United Kingdom ��Department of Geosciences, Princeton) whereas lessening it on others. We quantified how the agricultural utility of South African conservation

Bradley, Bethany

418

Atmos. Chem. Phys., 12, 9891002, 2012 www.atmos-chem-phys.net/12/989/2012/  

E-print Network

,***, A. Saiz-Lopez4,****, H. K. Roscoe1, E. W. Wolff1, and J. M. C. Plane4,***** 1British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK 2School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK 3School of Earth and the Environment, University of Leeds

Cambridge, University of

419

8, 51375181, 2008 CHABLIS overview  

E-print Network

7, 1 British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road and Physics Discussions Chemistry of the antarctic boundary layer and the interface with snow: an overview Institute for Atmospheric Science, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK

Boyer, Edmond

420

PPPL-3470 PPPL-3470 Road Map for a Modular Magnetic Fusion Program  

E-print Network

#12;PPPL Reports Disclaimer This report was prepared as an account of work sponsored by an agency: (865) 576-8401 Fax: (865) 576-5728 Email: reports@adonis.osti.gov This report is available PLT in 1980 and now up to the larger tokamaks (TFTR, JET and JT-60U) which have produced near break

421

Comprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests  

E-print Network

and the Environment, South Parks Road, Oxford OX1 3QY, UK, wDepartment of Forest Ecology and Management, SwedishComprehensive assessment of carbon productivity, allocation and storage in three Amazonian forests^nia, Manaus, Brazil, §Earth and Biosphere Institute, School of Geography, University of Leeds, LS2 9JT, UK

Malhi, Yadvinder

422

Green rust as a precursor for magnetite: an in situ synchrotron based study  

E-print Network

, showing the initial rapid formation of hexagonal sulphate green rust particles, followed by the corrosionGreen rust as a precursor for magnetite: an in situ synchrotron based study A. SUMOONDUR*, S. SHAW, University of Leeds, Leeds, LS2 9JT, UK ABSTRACT In this study, direct evidence for the formation

Benning, Liane G.

423

Formation of hydroxysulphate and hydroxycarbonate green rusts in the presence of zinc using time-resolved in situ small and wide  

E-print Network

Formation of hydroxysulphate and hydroxycarbonate green rusts in the presence of zinc using time and Environment, University of Leeds, Leeds, LS2 9JT, UK ABSTRACT The formation and transformation of hydroxysulphate (GRSO4) and hydroxycarbonate (GRCO3) Green Rusts were studied in situ using synchrotron-based time

Benning, Liane G.

424

Cooperative Jahn-Teller effect in a 2D mesoscopic C{60/n-} system with D5d symmetry adsorbed on buffer layers using Ising EFT model  

NASA Astrophysics Data System (ADS)

Fullerene molecules adsorbed on surfaces often show macroscopic average distortions. As charged ions C60n- are known to be Jahn-Teller (JT) active, it is suggested that these distortions could be a manifestation of cooperative JT effects (CJTE) due to interactions between neighbouring fullerene ions. In order to understand the distortion properties it is necessary to take correlations between different distortions into account. However, this can't easily be done in the mean field approximation usually used to describe the CJTE. We therefore propose an alternative procedure to describe 2D mesoscopic islands of C60 ions in which a pseudo vector spin overrightarrow{S} is evoked to represent degenerate JT-distorted states when the quadratic JT coupling is considered. This approach is analogous to methods used for 2D magnetic systems. We then use the differential operator technique in effective field theory within the Ising approach. We include the effects of weak surface interactions and dynamic motion between equivalent distortions via terms equivalent to anisotropy and a transverse field in magnetism respectively. For distortions to D5d symmetry, we determine single site correlations as a function of temperature, the macroscopic average distortion describing a structural phase transition, and the isothermal response function. Phase diagrams are presented for relevant cases of the system parameters.

Abou Ghantous, M.; Moujaes, E. A.; Dunn, J. L.; Khater, A.

2012-06-01

425

Mon. Not. R. Astron. Soc. 000, 000{000 (0000) Printed 24 February 2005 (MN L A T E X style le v2.2) Probing the circumstellar structures of T Tauri stars and  

E-print Network

2BZ, UK 2 School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, UK 3 The School of Physics and Astronomy, E C Stoner Building, Leeds, LS2 9JT, UK received, accepted ABSTRACT We present H#11, probing much larger scales. For the Herbig Ae stars AB Aur, MWC 480 and CQ Tau, we #12;nd the polarisation

Vink, Jorick

426

Dental Topics for Medical Students  

ERIC Educational Resources Information Center

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)

Lorber, Mortimer

1976-01-01

427

Evolving Levels for Super Mario Bros Using Grammatical Noor Shaker, Miguel Nicolau, Georgios N. Yannakakis, Member, IEEE,  

E-print Network

with or without human designer interaction. Using these computational techniques, it is not only possible representation. This allows level designers to NS, GNY and JT are with the Center for Computer Games Research of the GE-based level generator is analyzed and quantitatively compared to other feature

Togelius, Julian

428

The role of the OH species in high-kpolycrystalline silicon gate electrode interface reactions  

E-print Network

, the substrates were cleaned in J.T. Baker Clean 100, rinsed in de-ionized DI water, and dipped in buffered oxideThe role of the OH species in high-k�polycrystalline silicon gate electrode interface reactions layer is exposed to sufficient water vapor before polysilicon deposition, annealing at 1050 °C for 10

Gougousi, Theodosia

429

Nematodes and Regulatory T Cells Katherine A Smith and Rick M Maizels  

E-print Network

Nematodes and Regulatory T Cells Katherine A Smith and Rick M Maizels Institute of Immunology and Infection Research University of Edinburgh, Edinburgh, EH9 3JT, UK For "Parasitic Nematodes, Second Edition.maizels@ed.ac.uk #12;Smitn & Maizels, Nematodes and T Regulatory Cells Page 2 Introduction The survival of nematode

Maizels, Rick

430

Macrophages in chronic type 2 inflammation have a novel phenotype characterized by the abundant expression of Ym1 and Fizz1 that can  

E-print Network

3JT, UK Abstract Using a murine model of nematode infection, we have discovered macrophages. These nematode-elicited macrophages (NeMf) are characterized by two unique features: the ability to actively by treatment of cultured macrophages with Th2 cytokines. In future, we hope to use in vitro analysis to help

Allen, Judith

431

CURRICULUM VITAE Terry D. Ellis, PhD, PT, NCS  

E-print Network

Refereed Publications: Ellis, T., Cavanaugh, J.T., Earhart, G.M., Ford, M.P., Foreman, K.B., Dibble, L Disease. Physical Therapy (in press) #12;3 Schenkman M, Ellis T, Christiansen C, Baron AE, Tickle-Degnen L. BMC Neurology 2010,10:110 Tickle-Degnen L, Ellis T, Saint-Hilaire MH, Thomas C, Wagenaar RC. Self

Guenther, Frank

432

A Couples Group of Medical Students  

ERIC Educational Resources Information Center

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)

Porter, Kenneth; And Others

1976-01-01

433

Amending the Amendments  

ERIC Educational Resources Information Center

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)

McNamara, William

1976-01-01

434

The inverse problem for the vocal tract: Numerical methods, acoustical experiments, and speech synthesis  

E-print Network

-lengthsequencesofmeasuredarea functions.Tothebestofourknowledge,thisisthefirstinstanceofcontinuousspeechsynthesized from direct measurements of area functions. PACSnumbers:43.70.Bk,43.70.Qa,43.70.Ny,43.70.Jt INTRODUCTION In thisarticlewewilldescribeourrecentexperiments on estimation of vocal tract area functions from transient acousticalmeasurementsatthelips

Allen, Jont

435

Environmental Modelling & Software 15 (2000) 681692 www.elsevier.com/locate/envsoft  

E-print Network

-scale air pollution modelling using adaptive unstructured meshes A.S. Tomlin a,* , S. Ghorai a , G. Hart of Computer Studies, University of Leeds, Leeds LS2 9JT, UK Abstract High resolution models of air pollution but less so in meteorological and air pollution models. However, it is well known that grid resolution has

Utah, University of

436

SOURCE SAMPLING FINE PARTICULATE MATTER: WOOD-FIRED INDUSTRIAL BOILER: PROJECT REPORT/SUMMARY  

EPA Science Inventory

NRMRL-RTP-229 Dayton, D.P., and Bursey, J.T. Source Sampling Fine Particulate Matter: Wood-fired Industrial Boiler. EPA-600/R- 01/106, Available: NTIS.10/29/2001 The report provides a profile for a wood-fired industrial boiler equipped with a multistage electrostatic precipitato...

437

The role of thrombin in gliomas Y. HUA,* L. TANG,* R. F. KEEP,* T. SCHALLERT,* M. E. FEWEL,* K. M. MURASZKO,* J. T. HOFF*  

E-print Network

IN FOCUS The role of thrombin in gliomas Y. HUA,* L. TANG,* R. F. KEEP,* T. SCHALLERT,*à M. E, Muraszko KM, Hoff JT, Xi G. The role of thrombin in gliomas. J Thromb Haemost 2005; 3: 1917­23. See also thrombin inhibitor, reduces brain edema and neurologic deficits in a C6 glioma model. Objectives

Schallert, Tim

438

Meteorology Data Nodes A cheap solution using Raspberry Pis  

E-print Network

Meteorology Data Nodes A cheap solution using Raspberry Pis Jt Whissel 2012 The process of gathering weather data by the use of technology has been around for decades. However with the ever expanding growth of its advances, the cost of the equipment for collecting the data has not diminished. This lack

Miles, Will

439

DTP | Toxicology and Pharmacology Branch (TPB)  

Cancer.gov

Donzanti, B.A., J.S. Driscoll, J.E. Tomaszewski, J.S. Roth, P. Tosca, M. Placke, A. Singer, J.T. Yarrington and J.A. Kelley, 1994. Acute Cardiotoxicity of the Anti-HIV Dideoxynucleoside, F-ddA, in the Rat. Fund. Appl. Toxicol., 27, 167-176.

440

Letter From the Barricades: What Price CUNY?  

ERIC Educational Resources Information Center

A student at Lehman College describes student reaction to the threat of loss of free tuition and open admissions at New York City University. To money managers, he contends, they represent a "noble tradition," to students economic necessities. (Editor/JT)

Katz, Jeffrey M.

1976-01-01

441

Mixed-genotype infections of the rodent malaria Plasmodium chabaudi are more infectious to mosquitoes  

E-print Network

121 Mixed-genotype infections of the rodent malaria Plasmodium chabaudi are more infectious, Institute of Cell, Animal and Population Biology, King's Buildings, West Mains Road, Edinburgh EH9 3JT, UK. 1992). In Tanzania, Senegal and Papua New Guinea, for example, PCR analysis has shown that between 70

Read, Andrew

442

Received 19 November 2002 Accepted 5 February 2003  

E-print Network

implications for the design and use of imperfect vaccines in public- and animal-health programmes. Keywords vaccination: some epidemiological and evolutionary consequences Sylvain Gandon* , Margaret Mackinnon, Sean Nee 3JT, UK An aim of some vaccination programmes is to reduce the prevalence of an infectious disease

Read, Andrew

443

e-publishing Received 19 November 2002  

E-print Network

. These results have practical implications for the design and use of imperfect vaccines in public- and animal-health Imperfect vaccination: some epidemiological and evolutionary consequences Sylvain Gandon* , Margaret of Edinburgh, Edinburgh EH9 3JT, UK An aim of some vaccination programmes is to reduce the prevalence

444

Control of alongshore-oriented sand spits on the dynamics of a wave-dominated coastal system (Holocene deposits, northern Gulf of Lions, France)  

E-print Network

(Holocene deposits, northern Gulf of Lions, France) Olivier Raynal a, , Frédéric Bouchette a,1 , Raphaël Communicated by J.T. Wells Keywords: sand spit transgression deglacial deposits Gulf of Lions alongshore drift coastal tract The Maguelone shore extends along the northern coast of the Gulf of Lions, west of the Rhône

Demouchy, Sylvie

445

Does hydrological connectivity improve modelling of coarse sediment delivery in upland environments?  

E-print Network

? Simon C. Reid a , Stuart N. Lane b,, David R. Montgomery c , Christopher J. Brookes d a School of Geography, University of Leeds, Leeds, LS2 9JT, UK b Department of Geography, University of Durham, Durham, DH1 3LE, UK c Department of Earth and Space Sciences/Quaternary Research Center, University

Montgomery, David R.

446

Efficient Stochastic Local Search for MPE Solving Frank Hutter  

E-print Network

been explored, but were found to be not competitive with state-of-the- art branch & bound methods], junc- tion tree (JT) [Cowell et al., 1999] and conditioning tech- niques [Pearl, 1988], but also [Boykov et al., 2001]. B&B approaches have recently been shown to be state- of-the-art methods in MPE

Hutter, Frank

447

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

ERIC Educational Resources Information Center

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)

Siegel, Stephen A.

1975-01-01

448

Simulated Game Playing in Law School; An Experiment  

ERIC Educational Resources Information Center

Describes the successful use of six simulated games in a commercial law class of 84 students and discusses teacher and student evaluation of their effectiveness. The six games, three with a legislative setting and three with a court setting, are included. (JT)

King, Donald B.

1974-01-01

449

Effectiveness of an International Health Elective As Measured by NBME Part II  

ERIC Educational Resources Information Center

National Board of Medical Examiner's exam results show that U.S. medical students who participated between 1968 and 1974 in Yugoslav or Israeli international fellowship programs sponsored by the Association of American Medical Schools and the U.S. Public Health Service gained knowledge of preventive medicine and public health. (JT)

Waddell, Wendy; And Others

1976-01-01

450

~tm nftQt :!lnuntains Published by THE JUNIOR CLASS  

E-print Network

UhUI 1904 #12;WlJt lltniurr.aity College of Letters and Science College of Applied Science College spirit of American genius. \\Vhen the foundation principles were laid for our great scheme of government are the direct beneficiaries. It would seem that in noting the progress of a college or a uni- versity there must

O'Laughlin, Jay

451

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...

452

College Stores 1975--A Challenge to the Publishers  

ERIC Educational Resources Information Center

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)

Davis, Howard W.

1976-01-01

453

International Turfgrass Society Research Journal Volume 11, 2009  

E-print Network

and linear traction. Topdressing with a porous ceramic amendment, calcined clay, had no effect on surface-turfed basepath, infill, synthetic turf, calcined clay, PENNFOOT J.T. Brosnan, Dept. of Plant Sciences as the addition of soil conditioners like calcined clay. Calcined clay is a porous ceramic amendment often applied

Kaye, Jason P.

454

Distinct Cell Wall Architectures in Seed Endosperms in Representatives of the Brassicaceae and Solanaceae1[C][W][OA  

E-print Network

species, a crucial role has been demonstrated for the seed endosperm during germination. The endosperm hasDistinct Cell Wall Architectures in Seed Endosperms in Representatives of the Brassicaceae of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom (K.J.D.L., J.P.K.); Wageningen Seed

Leubner, Gerhard

455

2010 BOTANY AND PLANT PATHOLOGY PUBLICATIONS Armstrong, Donald  

E-print Network

2010 BOTANY AND PLANT PATHOLOGY PUBLICATIONS Armstrong, Donald a. REFEREED JOURNAL ARTICLES Mc in plants. Methods Mol Biol. 592, 51-7. Cuperus, J.T., Montgomery, T.A., Fahlgren, N., Burke, R.T., Townsend.J., Carrington, J.C. 2010. Arabidopsis RNA-Dependent RNA polymerases and Dicer-Like proteins in antiviral defense

Grünwald, Niklaus J.

456

BIOTROPICA 39(3): 416421 2007 10.1111/j.1744-7429.2007.00264.x Explaining Leaf Herbivory Rates on Tree Seedlings in a Malaysian Rain Forest  

E-print Network

herbivores and their feeding preferences. Characteristics of the leaves related to their defense, herbivore preferences will play a crucial role in determining the amount of damage received by a given plant of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK Daisy H. Dent Plant and Soil Science, Cruickshank

Nottingham, University of

457

Texas A&M University College of Agriculture and Life Sciences  

E-print Network

Mr. Thomas (Tom) W. Smith `57 Mr. Vinson E. Kirchner `66 1998 Dr. Dial F. Martin `39 Dr. James R. Watson `45 Mr. Tommie Vaughn `41 1999 Mr. Nathan Boardman `56 Mr. John L. Hagaman `61 Dr. Richard P. Mc. Zay W. Gilbreath `62 Mr. J.T. Smith `73 2004 Mr. Robert L. Bob Cook `65 Mr. James L. Faubion `54 Mr

458

Hierarchical Classification via Orthogonal Transfer?  

E-print Network

May 2, 2011 ... the set of children of i, and S(i) the set of siblings of i. ... i.e., ui = wi ? wp(i), where p(i) denotes the parent node of i. ..... The form of g? above indeed looks as if it were computed by following the subdifferential ... Up- dating the upper bounds J(t

2011-05-02

459

Wednesday, February 4, 2004 Search Archives  

E-print Network

Subscribe About us Contact us Privacy Policy Advertise Nifco Shukan ST JT Weekly Travel Service Travel, Science and Technology Ministry, is heading the delegation to Russia. Science minister Takeo Kawamura. Russia sticks to its guns, backs France for fusion reactor Yamato Inaba, senior vice science minister

460

Thursday, January 29, 2004 Search Archives  

E-print Network

Subscribe About us Contact us Privacy Policy Advertise Nifco Shukan ST JT Weekly Travel Service Travel of education, culture, sports, science and technology, said he is "convinced" the Japanese bid will get the nod World wide hotels Simmons Ohto Nifsan Technology minister Takeo Kawamura said Wednesday that Japan

461

Monday, December 22, 2003 Search Archives  

E-print Network

Subscribe About us Contact us Privacy Policy Advertise Nifco Shukan ST JT Weekly Travel Service Travel." While avoiding citing specific countries, Hosoda, who was formerly state minister in charge of science and technology, said two supported Japan and two threw their support behind the EU bid. According to conference

462

Polydispersity and the fluid-crystalline phase transition E. Dickinson and R. Parker  

E-print Network

Department of Food Science, University of Leeds, Leeds LS2 9JT, U.K. (Re~u le 15 octobre 1984, accepte le 17-232 ~ 15 MARS 1985, :-1 Classification Physics Abstracts 64. 70D - 82.70 Freezing occurs at a first. An obvious inference is that the freezing transition disappears altogether above a certain « critical» degree

Paris-Sud XI, Université de

463

Submitted to Physics Letters A 24/4/2001 Global bifurcations in the Takens{Bogdanov  

E-print Network

with D 4 symmetry is governed by a one-dimensional map near the gluing bifurcation and near the O(2Submitted to Physics Letters A 24/4/2001 Global bifurcations in the Takens{Bogdanov normal form of Leeds, Leeds, LS2 9JT, UK Abstract The dynamics of the normal form of the Takens{Bogdanov bifurcation

Rucklidge, Alastair

464

BERRY, Pauline.M. (1991) ``A Predictive Model for Satisfying Conflicting Objectives in Scheduling Problems'', Ph.D. Thesis, Dept. of Computer Science, University of Strathclyde, Glasgow.  

E-print Network

. European Conference on Artificial Intelligence (ECAI­92), Vienna, July 1992. BUCHANAN, J.T. (1982) Discrete(3):106­124,: Computational Mechanics Publi­ cation. CHEESEMAN, Peter. (1985) ``In Defense of Probability'', Proc. 8th Int. Joint Conf. on AI, (IJCAI­85), pp1002­1009. COHEN, P.R. (1985) Heuristic Reasoning about Uncertainty

Berry, Pauline M.

465

vertebrate sensory system  

Microsoft Academic Search

3JT UK Nociception is the detection of a noxious, tissue damaging stimulus and is sometimes accompanied by a reflex response such as withdrawal. Pain perception, as distinct from nociception, has been demonstrated in birds and mammals but has not been systematically studied in lower vertebrates. We assessed whether a fish possessed cutaneous nociceptors capable of detecting noxious stimuli and if

Lynne U. Sneddon; Victoria A. Braithwaite; Michael J. Gentle

466

Preliminary design study of astronomical detector cooling system  

NASA Technical Reports Server (NTRS)

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.

Norman, R. H.

1976-01-01

467

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

NASA Astrophysics Data System (ADS)

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.

Shimazaki, T.

2013-09-01

468

Gas phase precursors to anthropogenic secondary organic aerosol: Using the Master Chemical Mechanism to probe detailed  

E-print Network

d , M.J. Pilling e a National Centre for Atmospheric Science, University of Leeds, Leeds LS2 9JT, UK hydrocarbons Chemical ionisation reaction time-of-flight mass spectrometry a b s t r a c t A detailed gas Reaction Time-of-Flight Mass Spectrometer (CIR-TOF-MS). Supporting gas and aerosol measurements have also

469

Atmos. Chem. Phys., 7, 53715390, 2007 www.atmos-chem-phys.net/7/5371/2007/  

E-print Network

. Ingham1, M. J. Pilling1, and P. W. Seakins1 1School of Chemistry, University of Leeds, Leeds LS2 9JT, UK dependent kinetics of the chlorine atom reaction with ethene and the reaction of O3 and t-2-butene

Paris-Sud XI, Université de

470

Introduction to Nuclear Physics Physics 124  

E-print Network

Introduction to Nuclear Physics Physics 124 Solution Set 6 J.T. Burke January 18, 2000 1 #12.2. In Krane's derivation he takes into account the average energy loss per interaction whereas I treated every an average energy of 200 MeV for a 235 U produced chain reaction. a) The average power of a research reactor

Budker, Dmitry

471

Performance of a Low-Power Cylindrical Hall Thruster IEPC-2005-011  

E-print Network

International Electric Propulsion Conference, Princeton University October 31 ­ November 4, 2005 Kurt A. Polzin , Thomas E. Markusic , Boris J. Stanojev and Amado Dehoyos§ Propulsion Research Center NASA - Marshall of the thrust stand arm `zero'-position. Nomenclature µe Magnetic Moment, J/T Isp Specific Impulse, sec B, B

472

Scientific Research and Agricultural Innovation in Israel  

ERIC Educational Resources Information Center

Traces the development and interrelationships of agriculture and agricultural research in Israel since 1920, concluding that major contributing factors to successful relationship between research and production in agriculture are a rise in the educational level of the agricultural population and a thorough knowledge of the soil and climate. (JT)

Ben-David, Joseph; Katz, Shaul

1975-01-01

473

Meeting a Higher Education Goal Through a Student Volunteer Counseling Program  

ERIC Educational Resources Information Center

To bridge the schism between academic and student life departments and produce programs offering opportunities for both cognitive development and personal growth, Brooklyn College developed a formal content oriented course, Basic Training for Peer Counselors, as part of a training program for student volunteer counselors in the Drop-In Center. (JT)

Snadowsky, Alvin; Meyer, Daniel

1975-01-01

474

POTENTIAL METHODS FOR IMPROVING PEDESTAL TEMPERATURES AND FUSION PERFORMANCE  

E-print Network

. Dorland (U. Md), M. A. Beer (PPPL M. Kotschenreuther (U. Texas) FIRE Workshop, May 2, 2000 Based on paper (1.17 - 0.65a/R) 2 AiR 2a (Hammett, Dorland, Kotschenreuther, Beer, PPPL-3360 (1999)) #12;#12;JT, and modest density peaking. (Hammett, Dorland, Kotschenreuther, Beer, PPPL-3360 (1999)) #12;CONCLUSIONS

475

NITRATE MOVEMENT IN SOUTHEASTERN COASTAL PLAIN SOILS UNDER CONSERVATION-TILLED VEGETABLE PRODUCTION  

E-print Network

NITRATE MOVEMENT IN SOUTHEASTERN COASTAL PLAIN SOILS UNDER CONSERVATION-TILLED VEGETABLE PRODUCTION G.D. Hoyt1 , D.C. Sanders2 , J.T. D.R. Decoteau3 , ABSTRACT Movement of soil nitrates by leaching. This study measured soil nitrate-N with depth at planting and after cucumber harvest at Clinton, NC, Florence

Decoteau, Dennis R.

476

Pure Mathematics in Australia  

ERIC Educational Resources Information Center

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)

Bloom, W. R.; And Others

1975-01-01

477

T cells do not mediate within-host competition between genetically  

E-print Network

parasites Victoria C. Barclay1,*, Lars Ra°berg2 , Brian H. K. Chan1, , Sheila Brown1 , David Gray1 and Andrew F. Read1, 1 School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK 2

Read, Andrew

478

Integrating Content on Feminism and Racism into the Social Work Curriculum  

ERIC Educational Resources Information Center

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)

Loewenstein, Sophie F.

1976-01-01

479

Mind Meld Issue 1  

E-print Network

Umed .the .to.6.6 ?k:t6 a de.UbVtate move by Spoc.k, who had been given c.ommand a6.te.Jt K-Utk'.6 c.oWt.tmaJttial, .to gain Jtevenge 60Jt K-Utk'.6 c.on vic.tion. Spoc.k ?k:t6 .then db.,honoJtab.ty db.,c.haJtged 6Jtom .the 6.teet, emed 6Jtom Vulc....an and ?k:t6 60Jtc.ed out 06 Fede.Jtation .te.JtJU.toJty. Mc.Coy and Sc.o.tty .tead K-Utk .to Spoc.k, who ha.6 had .to keep hidden. bec.aU6e 06 hb., eme. Spoc.k invde..6 K-Utk .to join him on E.6kaJt, hb., c.ho.6en home, and bec.ome a paJtt on hb., -tmpo...

Multiple Contributors

1984-01-01

480

The Emerging Consumer Movement in Education  

ERIC Educational Resources Information Center

The consumer movement seeks a better balance between institutional rights and those of the student who contracts for educational services. The author discusses how and why issues of consumer rights--to be safe, to be informed, to choose, and to be heard--are now unexpectedly confronting higher education. (Editor/JT)

Stark, Joan S.

1976-01-01

481

Bookstore in Trouble: The Proverbial Iceberg  

ERIC Educational Resources Information Center

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)

Sanderson, Ivan L.

1975-01-01

482

Published in IET Control Theory and Applications Received on 15th October 2007  

E-print Network

nonlinear systems with time delay using scaled sliding surface M.-S. Koo1 H.-L. Choi2 J.-T. Lim1 1 in [12]. In [13, 14], time-delay nonlinear systems can be asymptotically stabilised by a sliding mode considered system, the nonlinear function cannot be directly cancelled by the input due to a time delay

Lim, Jong-Tae

483

Choosing a Women's College  

ERIC Educational Resources Information Center

A comparative study of women at three women's colleges and one coeducational college showed major reasons for college choice to be academic criteria, institutional characteristics, school size, and social factors. Compared to students in a 1958 study they emphasized social features and de-emphasized others' advice and personal values. (JT)

Brush, Lorelei R.

1976-01-01

484

Biogeosciences, 9, 775801, 2012 www.biogeosciences.net/9/775/2012/  

E-print Network

-Planck-Institut f¨ur Biogeochemie, Postfach 100164, 07701, Jena, Germany 2School of Geography, University of Leeds, LS2 9JT UK 3Institito Nacional de Pesquisas da Amaz^onia, Manaus, AM, Brazil 4Departamento de Ecologia, Universidade de Bras´ilia, DF, Brazil 5Dept. of Plant Ecology and Biodiversity, Utrecht

Malhi, Yadvinder

485

Drip-tips are Associated with Intensity of Precipitation in the Amazon Rain Forest Ana C. M. Malhado1,9  

E-print Network

/n, Prado, Maceio´, AL, 57010-020, Brazil 2 School of Geography and the Environment, University of Oxford of Geography, University of Leeds, Leeds, LS2 9JT, U.K. 5 School of Marine and Tropical Biology, James Cook, 45200-000, Brazil ABSTRACT Drip-tips are a common feature of the leaves of rain forest trees

Malhi, Yadvinder

486

Biogeosciences, 7, 4355, 2010 www.biogeosciences.net/7/43/2010/  

E-print Network

, Colombia 4Museu Paraense Emilio Goeldi, 66077-530 Belem, Brazil 5Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK 6INRA, UMR Institute, School of Geography, University of Leeds, Leeds LS2 9JT, UK 10Universidad de los Andes, Bogot

Malhi, Yadvinder

487

Received 26 Sep 2013 | Accepted 12 Feb 2014 | Published 18 Mar 2014 Size and frequency of natural forest disturbances  

E-print Network

´lite, Campinas, Sao Paulo CEP 13070-115, Brazil. 6 Environmental Change Institute, School of Geography School of Geography, University of Leeds, Leeds LS2 9JT, UK. 4 USDA Forest Service, International), CP 478, Manaus, Amazonas 69011-970, Brazil. 8 EMBRAPA Amazo^nia Oriental (CPATU), Santare´m, Para

Malhi, Yadvinder

488

Confronting model predictions of carbon fluxes with measurements of Amazon forests subjected to experimental  

E-print Network

and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; 2 School of Geography, University of Leeds, Leeds, LS2 9JT, UK; 3 Environmental Change Institute, School of Geography and the Environment VicÃ?osa, VicÃ?osa, CEP 36570-000, Minas Gerias, Brazil; 8 School of GeoSciences, University of Edinburgh

Moorcroft, Paul R.

489

Biogeosciences, 9, 33813403, 2012 www.biogeosciences.net/9/3381/2012/  

E-print Network

for Research in Amazonia (INPA), C.P. 478, Manaus, Amazonas, 69011-970, Brazil 11Geography, College of Life of Geography, University of Leeds, Leeds, LS2 9JT, UK 2School of Earth and Environmental Science, James Cook University, Cairns, Qld 4870, Australia 3Department of Geography, University College London, UK 4RAINFOR

Malhi, Yadvinder

490

Biogeosciences, 8, 10811106, 2011 www.biogeosciences.net/8/1081/2011/  

E-print Network

,******, H. W¨oll31, and J. Lloyd1,*** 1Earth and Biosphere Institute, School of Geography, University of Leeds, Leeds, LS2 9JT, UK 2Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, Brazil 3Forestry Boliviana (PROMAB), P.O. Box 107, Riberalta, Bolivia 6School of Geography and Geosciences, Univ. of St

Chave, Jérôme

491

LETTER Fast demographic traits promote high diversification rates of Amazonian trees  

E-print Network

School of Geography, University of Leeds, Leeds, LS2 9JT, UK 2 Royal Botanic Garden Edinburgh, Edinburgh^onia, CEP 69067-375, Manaus, Brazil 11 INRA, UMR EEF INRA-Universite de Lorraine, 54280, Champenoux, France, Austin TX 78712, USA 15 Museu Paraense Emilio Goeldi, CEP 66040-170, Belem, Brazil 16 School

Malhi, Yadvinder

492

, 20120155, published 22 April 20133682013Phil. Trans. R. Soc. B Thomas L. Powell, Scott R. Saleska, Luis A. Solorzano and Jingfeng Wang  

E-print Network

-000, Brazil 4 School of Geography, University of Leeds, Leeds LS2 9JT, UK 5 Organismic and Evolutional Biology Hole Road, Falmouth, MA 02540, USA 2 Environmental Change Institute, School of Geography Catarina, Av. Mauro Ramos, 950 Centro 88020-302, Florianopolis, Santa Catarina, Brazil 7 Ecology

Malhi, Yadvinder

493

Agricultural and Forest Meteorology 182183 (2013) 111127 Contents lists available at ScienceDirect  

E-print Network

, Brazil p School of Geography, University of Leeds, Leeds LS2 9JT, UK q Key Laboratory of Semi , Xubin Zenggg a Centro de Previsão do Tempo e Estudos Climáticos (CPTEC), Cachoeira Paulista, SP, Brazil b Instituto Nacional de Pesquisas Espaciais (INPE), Brazil c Earth System Science Interdisciplinary

Jain, Atul K.

494

Droughtmortality relationships for tropical forests Oliver L. Phillips1  

E-print Network

Change, School of Geography, University of Leeds, Leeds LS2 9JT, UK; 2 Environmental Change Institute, School of Geography and Environment, Oxford University, Oxford OX1 3QY, UK; 3 Jardi´n Bota´nico de, 66077-830 Bele´m PA, Brazil; 5 Universidad Nacional de Colombia, Kilo´metro 2 Via Tarapaca´, Leticia

Slik, Ferry

495

Geosci. Model Dev., 7, 711723, 2014 www.geosci-model-dev.net/7/711/2014/  

E-print Network

Pesquisas da Amazônia, 69060-001 Manaus, Brazil 3School of Geography, University of Leeds, Leeds LS2 9JT, UK, School of Geography and the Environment, University of Oxford, Oxford OX1 3QY, UK 2Instituto Nacional de

Malhi, Yadvinder

496

Some Thoughts About Thomas More and Legal Education  

ERIC Educational Resources Information Center

Considers issues to be faced by law graduates in the years ahead, reflecting on More's affirmation that he was the king's obedient servant but God's first, and emphasizing the need for students to be cognizant of values transcending the legal and political system in which they will function. (JT)

Galvin, Charles O.

1974-01-01

497

Evaluation of a Thrustmeter for Measuring In-Flight Thrust of Turbojet Engines.  

National Technical Information Service (NTIS)

An airborne type thrust measuring instrument was developed and subsequently tested on both a J79-GE-8 turbojet engine mounted on a thrust stand in a laboratory altitude cell and a JT3C-7 turbojet engine aboard a Boeing 720 aircraft. The thrustmeter system...

R. F. Salmon

1966-01-01

498

774 BIOCHEMICAL SOCIETY TRANSACTIONS Bennett, J. (1983) Biochem. J. 212, 1-13  

E-print Network

and dephosphorylation reactions do in- deed accompany their respective light-state transitions (Telfer et al., 1983-174 Protein phosphorylation and optimal production of ATP in photosynthesis JOHN F. ALLEN Department of Plant Sciences, Baines Wing, University of Leeds. Leeds LS2 9JT. U.K. For green-plant photosynthesis

Allen, John F.

499

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-print Network

parameters. Hence we propose to use all three machines in this study. Stability calculations with the ELITE propose to study the dependence of pedestal structure (heights, widths, and gradients) on aspect ratio/ empirical justification Previous scaling studies of the H-mode Te pedestal width between DIII-D and JT-60U

Princeton Plasma Physics Laboratory

500

Development of an Arcellacea (testate lobose amoebae) based transfer function for sedimentary Phosphorus in lakes  

E-print Network

Phosphorus in lakes R. Timothy Patterson a, , Helen M. Roe b , Graeme T. Swindles c a Ottawa Kingdom c School of Geography, University of Leeds, Leeds, LS2 9JT, United Kingdom a b s t r a c ta r t i deshrinking (RMSEPjack-77pp; r2 jack=0.68). The inferred reconstruction indicates that OP levels remained near

Patterson, Timothy