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Sample records for ka current leads

  1. Test results of the 18 kA EDIPO HTS current leads

    Wesche, Rainer; Bagnasco, Maurizio; Bruzzone, Pierluigi; Felder, Roland; Guetg, Marc; Holenstein, Manuel; Jenni, Markus; March, Stephen; Roth, Felix; Vogel, Martin

    2011-01-01

    For the new test facility EDIPO (European DIPOle), to be hosted by CRPP, two 18 kA HTS current leads were manufactured and successfully tested. The HTS module, made of AgMgAu/Bi-2223 tapes, is cooled only by heat conduction to the cold end, while the copper part is cooled by forced flow helium gas. The current leads were tested at low voltage up to the maximum current of 18 kA. The helium mass flow rates required for stable operation at various currents were determined. In addition to the steady state operation, the transient behavior in the case of a loss of flow was studied experimentally. The test results provide an estimate of the operational limits of the EDIPO HTS current leads.

  2. Test results of the 18 kA EDIPO HTS current leads

    Wesche, Rainer, E-mail: rainer.wesche@psi.ch [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom - Confederation Suisse, 5232 Villigen PSI (Switzerland); Bagnasco, Maurizio; Bruzzone, Pierluigi; Felder, Roland; Guetg, Marc; Holenstein, Manuel; Jenni, Markus; March, Stephen; Roth, Felix; Vogel, Martin [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association Euratom - Confederation Suisse, 5232 Villigen PSI (Switzerland)

    2011-10-15

    For the new test facility EDIPO (European DIPOle), to be hosted by CRPP, two 18 kA HTS current leads were manufactured and successfully tested. The HTS module, made of AgMgAu/Bi-2223 tapes, is cooled only by heat conduction to the cold end, while the copper part is cooled by forced flow helium gas. The current leads were tested at low voltage up to the maximum current of 18 kA. The helium mass flow rates required for stable operation at various currents were determined. In addition to the steady state operation, the transient behavior in the case of a loss of flow was studied experimentally. The test results provide an estimate of the operational limits of the EDIPO HTS current leads.

  3. Experience of 12 kA / 16 V SMPS during the HTS Current Leads Test

    Panchal, P.; Christian, D.; Panchal, R.; Sonara, D.; Purwar, G.; Garg, A.; Nimavat, H.; Singh, G.; Patel, J.; Tanna, V.; Pradhan, S.

    2017-04-01

    As a part of up gradation plans in SST-1 Tokamak, one pair of 3.3 kA rated prototype hybrid current leads were developed using Di-BSCCO as High Temperature Superconductors (HTS) and the copper heat exchanger. In order to validate the manufacturing procedure prior to go for series production of such current leads, it was recommended to test these current leads using dedicated and very reliable DC switch mode power supply (SMPS). As part of test facility, 12 kA, 16 VDC programmable SMPS was successfully installed, commissioned and tested. This power supply has special features such as modularity, N+1 redundancy, very low ripple voltage, precise current measurements with Direct Current Current Transformer, CC/CV modes with auto-crossover and auto-sequence programming. As a part of acceptance of this converter, A 5.8 mΩ water-cooled resistive dummy load and PLC based SCADA system is designed, developed for commissioning of power supply. The same power supply was used for the testing of the prototype HTS current leads. The paper describes the salient features and experience of state-of-art of power supply and results obtained from this converter during the HTS current leads test.

  4. Current leads for superconducting solenoids in a transportable Dewar flask for currents up to 1kA

    Shirshov, L.S.

    1981-01-01

    A simple design of the current lead for currents up to 1 kA into a transportable helium dewar with 22 mm neck diameter is described. The lead characteristics have been studied at various conditions. Examples of pulse superconducting solenoid usage, parmitting to achieve the magnetic field up to 3.3 T are given. The 1% field homogeneity has been obtained on a length of 90 mm [ru

  5. Towards a 20 kA high temperature superconductor current lead module using REBCO tapes

    Heller, R.; Bagrets, N.; Fietz, W. H.; Gröner, F.; Kienzler, A.; Lange, C.; Wolf, M. J.

    2018-01-01

    Most of the large fusion devices presently under construction or in operation consisting of superconducting magnets like EAST, Wendelstein 7-X (W7-X), JT-60SA, and ITER, use high temperature superconductor (HTS) current leads (CL) to reduce the cryogenic load and operational cost. In all cases, the 1st generation HTS material Bi-2223 is used which is embedded in a low-conductivity matrix of AgAu. In the meantime, industry worldwide concentrates on the production of the 2nd generation HTS REBCO material because of the better field performance in particular at higher temperature. As the new material can only be produced in a multilayer thin-film structure rather than as a multi-filamentary tape, the technology developed for Bi-2223-based current leads cannot be transferred directly to REBCO. Therefore, several laboratories are presently investigating the design of high current HTS current leads made of REBCO. Karlsruhe Institute of Technology is developing a 20 kA HTS current lead using brass-stabilized REBCO tapes—as a further development to the Bi-2223 design used in the JT-60SA current leads. The same copper heat exchanger module as in the 20 kA JT-60SA current lead will be used for simplicity, which will allow a comparison of the newly developed REBCO CL with the earlier produced and investigated CL for JT-60SA. The present paper discusses the design and accompanying test of single tape and stack REBCO mock-ups. Finally, the fabrication of the HTS module using REBCO stacks is described.

  6. Test results of a 20 kA high temperature superconductor current lead using REBCO tapes

    Heller, R.; Fietz, W. H.; Gröner, F.; Heiduk, M.; Hollik, M.; Lange, C.; Lietzow, R.

    2018-05-01

    The Karlsruhe Institute of Technology has developed a 20 kA high temperature superconductor (HTS) current lead (CL) using the second generation material REBCO, as industry worldwide concentrate on the production of this material. The aim was to demonstrate the possibility of replacing the Bi-2223/AgAu tapes by REBCO tapes, while for easy comparison of results, all other components are copies of the 20 kA HTS CL manufactured for the satellite tokamak JT-60SA. After the manufacture of all CL components including the newly developed REBCO module, the assembly of the CL has been executed at KIT and an experiment has been carried out in the CuLTKa test facility where the REBCO CL was installed and connected to a JT-60SA CL via a superconducting bus bar. The experiment covers steady state operation up to 20 kA, pulsed operation, measurement of the heat load at 4.5 K end, loss-of-flow-accident simulations, and quench performance studies. Here the results of these tests are reported and directly compared to those of the JT-60SA CL.

  7. Development and performance test results of 50 kA vapor-cooled current lead for ITER

    Sugimoto, Makoto; Isono, Takaaki; Hamada, Kazuya

    1998-01-01

    JAERI has developed 50 kA current leads for the International Thermonuclear Experimental Reactor (ITER). The Center Solenoid (CS) Model Coil program is under way by means of international collaboration in ITER-EDA. The CS model coil is being developed for ITER CS coil and is for demonstration for ITER construction. The performance test of the CS model coil will be carried out at the JAERI ITER common test facility (CTF). The current lead consists of the vertical lead and the connection lead. The vertical lead is a vapor-cooled type and has a cable-in-conduit geometry. The vertical lead was designed with a heat leak of 1.2 W/kA at a helium flow rate of 0.06 g/(s·kA). The measured heat leak satisfied the designed value. The connection lead was made from copper pipe soldered with NbTi superconducting wires. The pipe was stabilized by the superconducting wires and a cooling channel. The current lead was operated up to 60 kA. The design and the performance test results of 50 kA current leads are reported. The results meet the specifications for the CS model coil test and for the ITER real machine. (author)

  8. Design optimization of 600 A-13 kA current leads for the Large Hadron Collider project at CERN

    Spiller, D M; Al-Mosawl, M K; Friend, C M; Thacker, P; Ballarino, A

    2001-01-01

    The requirements of the Large Hadron Collider project at CERN for high-temperature superconducting (HTS) current leads have been widely publicized. CERN require hybrid current leads of resistive and HTS materials with current ratings of 600 A, 6 kA and 13 kA. BICC General Superconductors, in collaboration with the University of Southampton, have developed and manufactured prototype current leads for the Large Hadron Collider project. The resistive section consists of a phosphorus de-oxidized copper conductor and heat exchanger and the HTS section is constructed from BICC General's (Pb, Bi)2223 tapes with a reduced thermal conductivity Ag alloy sheath. We present the results of the materials optimization studies for the resistive and the HTS sections. Some results of the acceptance tests at CERN are discussed. (9 refs).

  9. Series Production of 13 kA Current Leads with Dry and Compact Warm Terminals

    Andersen, T P; Vullierme, B

    2005-01-01

    For the LHC magnet test benches 13 pairs of conventional helium vapour-cooled 13 kA current leads are required. The current leads have been designed and built by industry. Attention was given to economical and reliable design and to a design of the warm terminal in order to avoid any condensation. Three pairs of them were tested at CERN. The dry warm terminal enables voltage test at 4.1 kV at cold condition. The paper describes construction details and compares calculated and measured values of the main parameters.

  10. Conceptual design of a forced-flow-cooled 20-kA current lead using Ag-alloy-sheathed Bi-2223 high-temperature superconductors

    Heller, R.

    1994-11-01

    The use of high-temperature superconductors in current leads to reduce refrigeration power has been investigated by many groups in the past. Most used YBCO and Bi-2212 bulk superconductors, although their critical current density is not very high. In this paper, BI-2223 HTSC tapes sheathed with Ag alloys are used in the design of a 20-kA current lead because of their higher critical current in medium magnetic fields. The lead current of 20 kA is related to the coil current of the planned stellarator WENDELSTEIN 7-X. Forced-now helium cooling has been used in the design, allowing position-independent and well-controlled operation. The design characteristics of the lead are presented and 4-K helium cooling of the whole lead, as well as 60-K helium cooling of the copper part of the lead, is discussed. The power consumption at zero current, and the lead's behaviour in case of loss of coolant flow, are given, The results of the design allow extrapolation to current leads of the 50-kA range

  11. Conceptual design of a 20-kA current lead using forced-flow cooling and Ag-alloy-sheathed Bi-2223 high-temperature superconductors

    Heller, R.; Hull, J.R.

    1994-01-01

    High-temperature superconductors (HTSs), consisting of Bi-2223 HTS tapes sheathed with Ag alloys are proposed for a 20-kA current lead for the planned stellarator WENDELSTEIN 7-X. Forced-flow He cooling is used, and 4-K He cooling of the whole lead as well as 60-K He cooling of the copper part of the lead, is discussed. Power consumption and behavior in case of loss of He flow are given

  12. Current lead thermal analysis code 'CURRENT'

    Yamaguchi, Masahito; Tada, Eisuke; Shimamoto, Susumu; Hata, Kenichiro.

    1985-08-01

    Large gas-cooled current lead with the capacity more than 30 kA and 22 kV is required for superconducting toroidal and poloidal coils for fusion application. The current lead is used to carry electrical current from the power supply system at room temperature to the superconducting coil at 4 K. Accordingly, the thermal performance of the current lead is significantly important to determine the heat load requirements of the coil system at 4 K. Japan Atomic Energy Research Institute (JAERI) has being developed the large gas-cooled current leads with the optimum condition in which the heat load is around 1 W per 1 kA at 4 K. In order to design the current lead with the optimum thermal performances, JAERI developed thermal analysis code named as ''CURRENT'' which can theoretically calculate the optimum geometric shape and cooling conditions of the current lead. The basic equations and the instruction manual of the analysis code are described in this report. (author)

  13. A 13 kA current lead, measuring 1.5 m in length. The lower part consists of a high-temperature superconductor (Bi-2223), operating at between 50 K and 4.5 K, while the heat-exchanger upper part allows the current to be brought from room temperature to 50 K.

    2004-01-01

    A 13 kA current lead, measuring 1.5 m in length. The lower part consists of a high-temperature superconductor (Bi-2223), operating at between 50 K and 4.5 K, while the heat-exchanger upper part allows the current to be brought from room temperature to 50 K.

  14. Cryogenic current leads

    Zizek, F.

    1982-01-01

    Theoretical, technical and design questions are examined of cryogenic current leads for SP of magnetic systems. Simplified mathematical models are presented for the current leads. To illustrate modeling, the calculation is made of the real current leads for 500 A and three variants of current leads for 1500 A for the enterprise ''Shkoda.''

  15. Lead toxicity: current concerns.

    Goyer, R A

    1993-01-01

    Over the 20-year period since the first issue of Environmental Health Perspectives was published, there has been considerable progress in the understanding of the potential toxicity of exposure to lead. Many of these advances have been reviewed in published symposia, conferences, and review papers in EHP. This brief review identifies major advances as well as a number of current concerns that present opportunities for prevention and intervention strategies. The major scientific advance has be...

  16. Magnesium Diboride Current Leads

    Panek, John

    2010-01-01

    A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Dis covered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A. The lead assembly consists of 12 steelclad MgB2 wires, a tensioned Kevlar support, a thermal heat sink interface at 4 K, and base plates. The wires are soldered to heavy copper leads at the 17 K end, and to thin copper-clad NbTi leads at the 1.3 K end. The leads were designed, fabricated, and tested at the Forschungszentrum Karlsruhe - Institut foer Technische Physik before inclusion in Goddard's XRS (X-Ray Spectrometer) instrument onboard the Astro-E2 spacecraft. A key factor is that MgB2 remains superconducting up to 30 K, which means that it does not introduce joule heating as a resistive wire would. Because the required temperature ranges are 1.3-17 K, this provides a large margin of safety. Previous designs lost superconductivity at around 8 K. The disadvantage to MgB2 is that it is a brittle ceramic, and making thin wires from it is challenging. The solution was to encase the leads in thin steel tubes for strength. Previous designs were so brittle as to risk instrument survival. MgB2 leads can be used in any cryogenic application where small currents need to be conducted at below 30 K. Because previous designs would superconduct only at up to 8 K, this new design would be ideal for the 8-30 K range.

  17. Current leads for superconducting magnets

    Ishibashi, Kenji

    1989-01-01

    Current leads for superconducting magnets have been studied since 1960's. The technology of current leads may seem to have been established both in theory and experiment before the middle of 1970's. Nevertheless, a wide variety of superconducting magnets have been introduced in the last 15 years, and the demands for special current leads have increased in accordance to the variety. A steady advance has been made in the design theory and fabrication of current leads. This paper describes the recent current lead technology regarding the design theory, safety in accidents, and high current capability. (author)

  18. Large-capacity current leads

    Ballarino, A.

    2008-01-01

    Feeding superconducting magnets with reliable low-loss devices is a key issue for any cryo-electrical system. Conventional or HTS current leads can be used, and cooling methods, materials, and geometries can be chosen to optimize the thermo-electrical performance of the system. The LHC magnets are powered via more than 3000 current leads transporting altogether about 3 MA of current. With thousands of leads, the LHC lead project represents today the largest project of its kind ever undertaken. Following a review of the LHC lead project, an overview of the choices that can be made for the optimization of large capacity current leads is presented. Examples are given of other leads for large scale magnet systems for which the use of HTS is being envisaged

  19. Development of a 20kA current feedthrough using YBCO bulk conductors

    Maehata, Keisuke; Ishibashi, Kenji; Shintomi, Takakazu; Iwamoto, Akifumi; Maekawa, Ryuji; Mito, Toshiyuki

    2004-01-01

    In the phase II experiment of the Large Helical Device (LHD) of the National Institute for Fusion Science (NIFS), it is planned to operate the helical coils at 1.8 K by employing pressurized superfluid cooling to raise the magnetic field to 4 T with 17.3 kA. It is important to develop a 20kA-class current feedthrough into the 1.8 K region, but it must have a high current capacity and low heat leakage in the maximum magnetic leakage field of 1 T. Rectangle-shaped YBCO bulk conductors measuring 20 mm wide, 140 mm long and 10 mm thick were manufactured from square-pillar-shaped YBCO bulk materials for a 20 kA current. To check the quality of the bulk conductors, internal defects or cracks were detected by carrying out a precise survey of trapped magnetic flux. An assembled 20 kA current feedthrough was mounted in the λ-plate of a pressurized superfluid cooling cryostat. Experiments of current feeding into the 1.8 K region were carried out by operating the 20 kA current feedthrough. In the experiments, the transport current was kept at 20 kA for longer than 1,200 s. During the 20 kA operation, the current transport section of the YBCO bulk conductors remained in the superconducting state and the voltage drop between the YBCO bulk conductors and the copper electrode was observed to be constant. A contact resistance and the Joule heat generation in the joint region between the YBCO bulk conductors and the copper electrode were obtained as 1.45 nΩ and 0.72 W, respectively in the 20 kA operation. We have demonstrated the feasibility of using a 20 kA current feedthrough for the phase II experiment of the LHD. (author)

  20. High temperature superconductor current leads

    Zeimetz, B.; Liu, H.K.; Dou, S.X.

    1996-01-01

    Full text: The use of superconductors in high electrical current applications (magnets, transformers, generators etc.) usually requires cooling with liquid Helium, which is very expensive. The superconductor itself produces no heat, and the design of Helium dewars is very advanced. Therefore most of the heat loss, i.e. Helium consumption, comes from the current lead which connects the superconductor with its power source at room temperature. The current lead usually consists of a pair of thick copper wires. The discovery of the High Temperature Superconductors makes it possible to replace a part of the copper with superconducting material. This drastically reduces the heat losses because a) the superconductor generates no resistive heat and b) it is a very poor thermal conductor compared with the copper. In this work silver-sheathed superconducting tapes are used as current lead components. The work comprises both the production of the tapes and the overall design of the leads, in order to a) maximize the current capacity ('critical current') of the superconductor, b) minimize the thermal conductivity of the silver clad, and c) optimize the cooling conditions

  1. Current Leads, Links and Buses

    Ballarino, A

    2014-01-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  2. Current Leads, Links and Buses

    Ballarino, A [European Organization for Nuclear Research, Geneva (Switzerland)

    2014-07-01

    Electrical transfer from a room temperature power source to a superconducting system is done via conventional or superconducting current leads and superconducting buses or links. The principles of optimization of these devices are presented, with emphasis on the cryogenic, electrical, and superconductor related aspects that drive choices for a system.

  3. High Current, Low Voltage Power Converter [20kA, 6V] LHC Converter Prototype

    Jørgensen, H E; Dupaquier, A; Fernqvist, G

    1998-01-01

    The superconducting LHC accelerator requires high currents (~12.5kA) and relatively low voltages (~10 V) for its magnets. The need to install the power converters underground is the driving force for reduced volume and high efficiency. Moreover, the LHC machine will require a very high level of performance from the power converters, particularly in terms of DC stability, dynamic response and also in matters of EMC. To meet these requirements soft-switching techniques will be used. This paper describes the development of a [20kA,6V] power converter intended as a stable high-current source for D CCT calibration and an evaluation prototype for the future LHC converters. The converter is made with a modular concept with five current sources [4kA,6V] in parallel. The 4kA sources are built as plu g-in modules: a diode rectifier on the AC mains with a damped L-C passive filter, a Zero Voltage Switching inverter working at 20 kHz and an output stage (high frequency transformers, Schottky rectifi ers and output filter...

  4. A Low Heat Inleak Cryogenic Station for Testing HTS Current Leads for the Large Hadron Collider

    Ballarino, A; Gomes, P; Métral, L; Serio, L; Suraci, A

    1999-01-01

    The LHC will be equipped with about 8000 superconducting magnets of all types. The total current to be transported into the cryogenic enclosure amounts to some 3360 kA. In order to reduce the heat load into the liquid helium, CERN intends to use High Temperature Superconducting (HTS) material for leads having current ratings up to 13 kA. The resistive part of the leads is cooled by forced flow of gaseous helium between 20 K and 300 K. The HTS part of the lead is immersed in a 4.5 K liquid helium bath, operates in self cooling conditions and is hydraulically separated from the resistive part. A cryogenic test station has been designed and built in order to assess the thermal and electrical performances of 13 kA prototype current leads. We report on the design, commissioning and operation of the cryogenic test station and illustrate its performance by typical test results of HTS current leads.

  5. Current leads cooling for the series-connected hybrid magnets

    Bai, Hongyu; Marshall, William S.; Bird, Mark D.; Gavrilin, Andrew V.; Weijers, Hubertus W.

    2014-01-01

    Two Series-Connected Hybrid (SCH) magnets are being developed at the National High Magnetic Field Laboratory. Both SCH magnets combine a set of resistive Florida-Bitter coils with a superconducting outsert coil constructed of the cable-in-conduit conductor (CICC). The outsert coils of the two magnets employ 20 kA BSCCO HTS current leads for the power supply although they have different designs and cooling methods. The copper heat exchangers of the HTS current leads for the HZB SCH are cooled with forced flow helium at a supply temperature of 44 K, while the copper heat exchangers of HTS current leads for NHMFL SCH are cooled with liquid nitrogen at a temperature of 78 K in a self-demand boil-off mode. This paper presents the two cooling methods and their impacts on cryogenic systems. Their efficiencies and costs are compared and presented.

  6. The Anomalous Currents In The Front Foils of the JET Lost Alpha Diagnostic KA-2

    Cecil, F.E.; Kiptily, V.; Salmi, A.; Horton, A.; Fullard, K.; Murari, A.; Darrow, D.; Hill, K.

    2011-01-01

    We have examined the observed currents in the front foils of the JET Faraday cup lost alpha particle diagnostic KA-2. In particular, we have sought to understand the currents during Ohmic plasmas for which the ion flux at the detectors was initially assumed to be negligible. We have considered two sources of this current: plasma ions (both deuterium and impurity) in the vicinity of the detector (including charge exchange neutrals) and photoemission from scattered UV radiation. Based upon modeling and empirical observation, the latter source appears most likely and, moreover, seems to be applicable to the currents in the front foil during ELMy H-mode plasmas. A very thin gold or nickel foil attached to the present detector aperture is proposed as a solution to this problem, and realistic calculations of expected fluxes of lost energetic neutral beam ions during TF ripple experiments are presented as justification of this proposed solution.

  7. The Anomalous Currents In The Front Foils of the JET Lost Alpha Diagnostic KA-2

    Cecil, F. E.; Kiptily, V.; Salmi, A.; Horton, A.; Fullard, K.; Murari, A.; Darrow, D.; Hill, K.

    2011-05-04

    We have examined the observed currents in the front foils of the JET Faraday cup lost alpha particle diagnostic KA-2. In particular, we have sought to understand the currents during Ohmic plasmas for which the ion flux at the detectors was initially assumed to be negligible. We have considered two sources of this current: plasma ions both deuterium and impurity in the vicinity of the detector including charge exchange neutrals and photoemission from scattered UV radiation. Based upon modeling and empirical observation, the latter source appears most likely and, moreover, seems to be applicable to the currents in the front foil during ELMy H-mode plasmas. A very thin gold or nickel foil attached to the present detector aperture is proposed as a solution to this problem, and realistic calculations of expected fluxes of lost energetic neutral beam ions during TF ripple experiments are presented as justification of this proposed solution.

  8. Mock-up qualification and prototype manufacture for ITER current leads

    Zhou, Tingzhi, E-mail: tingszhou@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Lu, Kun; Ran, Qingxiang; Ding, Kaizhong; Feng, Hansheng; Wu, Huan; Liu, Chenglian; Song, Yuntao [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Niu, Erwu [CNDA, Ministry of Science and Technology, Beijing (China); Bauer, Pierre; Devred, Arnaud [Magnet Division, ITER Organization, Cadarache (France)

    2015-10-15

    Highlights: • Vacuum brazing and electron beam welding qualification. • Machine and assembly strategy of fin type heat exchanger. • Soldering and joint resistance test of superconducting joint. • Pre-preg technology with vacuum bag on insulation. - Abstract: Three types of high temperature superconducting current leads (HTSCL) are designed to carry 68 kA, 55 kA or 10 kA to the ITER magnets. Before the supply of the HTS current lead series, the design and manufacturing process is qualified through mock-ups and prototypes. Seven mock-ups, representing the critical technologies of the current leads, were built and tested successfully in the Institute of Plasma Physics of the Chinese Academy of Sciences (ASIPP) in 2013. After the qualification some design features of the HTS leads were updated. This paper summarizes the qualification through mock-ups. In 2014 ASIPP started the manufacture of the prototypes. The preparation and manufacturing process are also described.

  9. Thermal optimum analyses and mechanical design of 10-kA, vapor-cooled power leads for SSC superconducting magnet tests at MTL

    Shu, Q.S.; Demko, J.; Dorman, R.; Finan, D.; Hatfield, D.; Syromyatnikov, I.; Zolotov, A.; Mazur, P.; Peterson, T.

    1992-08-01

    The spiral-fin, 10-kA, helium vapor-cooled power leads have been designed for Superconducting Super Collider superconducting magnet tests at the Magnet Test Laboratory. In order to thermally optimize the parameters of the power leads, the lead diameters-which minimize the Carnot work for several different lengths, two different fin geometries, and two RRR values of the lead materials-were determined. The cryogenic refrigeration and liquefaction loads for supporting the leads have also been calculated. The optimum operational condition with different currents is discussed. An improved mechanical design of the 10-kA power leads was undertaken, with careful consideration of the cryogenic and mechanical performance. In the design, a new thermal barrier device to reduce heat conduction from the vacuum and gas seal area was employed. Therefore, the electric insulation assembly, which isolates the ground potential parts of the lead from the high-power parts, was moved into a warm region in order to prevent vacuum and helium leakage in the 0-ring seals due to transient cold temperature. The instrumentation for testing the power leads is also discussed

  10. Superconducting technology for overcurrent limiting in a 25 kA current injection system

    Heydari, Hossein; Faghihi, Faramarz; Sharifi, Reza; Poursoltanmohammadi, Amir Hossein [Center of Excellence for Power System Automation and Operation, Electrical Engineering Department, Iran University of Science and Technology (IUST), Tehran (Iran, Islamic Republic of)], E-mail: heydari@iust.ac.ir, E-mail: faramarz_faghihi@ee.iust.ac.ir, E-mail: reza_sharifi@ee.iust.ac.ir, E-mail: amirhosseinp@ee.iust.ac.ir

    2008-09-15

    Current injection transformer (CIT) systems are within the major group of the standard type test of high current equipment in the electrical industry, so their performance becomes very important. When designing high current systems, there are many factors to be considered from which their overcurrent protection must be ensured. The output of a CIT is wholly dependent on the impedance of the equipment under test (EUT). Therefore current flow beyond the allowable limit can occur. The present state of the art provides an important guide to developing current limiters not only for the grid application but also in industrial equipment. This paper reports the state of the art in the technology available that could be developed into an application of superconductivity for high current equipment (CIT) protection with no test disruption. This will result in a greater market choice and lower costs for equipment protection solutions, reduced costs and improved system reliability. The paper will also push the state of the art by using two distinctive circuits, closed-core and open-core, for overcurrent protection of a 25 kA CIT system, based on a flux-lock-type superconducting fault current limiter (SFCL) and magnetic properties of high temperature superconducting (HTS) elements. An appropriate location of the HTS element will enhance the rate of limitation with the help of the magnetic field generated by the CIT output busbars. The calculation of the HTS parameters for overcurrent limiting is also performed to suit the required current levels of the CIT.

  11. Superconducting technology for overcurrent limiting in a 25 kA current injection system

    Heydari, Hossein; Faghihi, Faramarz; Sharifi, Reza; Poursoltanmohammadi, Amir Hossein

    2008-09-01

    Current injection transformer (CIT) systems are within the major group of the standard type test of high current equipment in the electrical industry, so their performance becomes very important. When designing high current systems, there are many factors to be considered from which their overcurrent protection must be ensured. The output of a CIT is wholly dependent on the impedance of the equipment under test (EUT). Therefore current flow beyond the allowable limit can occur. The present state of the art provides an important guide to developing current limiters not only for the grid application but also in industrial equipment. This paper reports the state of the art in the technology available that could be developed into an application of superconductivity for high current equipment (CIT) protection with no test disruption. This will result in a greater market choice and lower costs for equipment protection solutions, reduced costs and improved system reliability. The paper will also push the state of the art by using two distinctive circuits, closed-core and open-core, for overcurrent protection of a 25 kA CIT system, based on a flux-lock-type superconducting fault current limiter (SFCL) and magnetic properties of high temperature superconducting (HTS) elements. An appropriate location of the HTS element will enhance the rate of limitation with the help of the magnetic field generated by the CIT output busbars. The calculation of the HTS parameters for overcurrent limiting is also performed to suit the required current levels of the CIT.

  12. Superconducting technology for overcurrent limiting in a 25 kA current injection system

    Heydari, Hossein; Faghihi, Faramarz; Sharifi, Reza; Poursoltanmohammadi, Amir Hossein

    2008-01-01

    Current injection transformer (CIT) systems are within the major group of the standard type test of high current equipment in the electrical industry, so their performance becomes very important. When designing high current systems, there are many factors to be considered from which their overcurrent protection must be ensured. The output of a CIT is wholly dependent on the impedance of the equipment under test (EUT). Therefore current flow beyond the allowable limit can occur. The present state of the art provides an important guide to developing current limiters not only for the grid application but also in industrial equipment. This paper reports the state of the art in the technology available that could be developed into an application of superconductivity for high current equipment (CIT) protection with no test disruption. This will result in a greater market choice and lower costs for equipment protection solutions, reduced costs and improved system reliability. The paper will also push the state of the art by using two distinctive circuits, closed-core and open-core, for overcurrent protection of a 25 kA CIT system, based on a flux-lock-type superconducting fault current limiter (SFCL) and magnetic properties of high temperature superconducting (HTS) elements. An appropriate location of the HTS element will enhance the rate of limitation with the help of the magnetic field generated by the CIT output busbars. The calculation of the HTS parameters for overcurrent limiting is also performed to suit the required current levels of the CIT

  13. Design chart of optimum current leads

    Ishibashi, K.; Katase, A.; Maechata, K.

    1986-01-01

    The heat flow through current leads is one of major heat losses in a superconducting magnet system. To reduce the heat flow, current leads have been optimized in a complex way by varying such quantities as conductor length, cross-sectional area, heat transfer coefficient and cooling perimeter. Therefore, this study is made to simplify the design procedure, and to explain the general characteristics of the current leads. A new combined parameter which takes turbulent flow into account is introduced in the present work to enable us to draw a useful design chart. This chart gives, to a wide variety of current leads, detailed information about the optimum design-viz. geometric dimensions, heat flow into liquid helium, and pressure drop of the cooling gas. Change of the cross-sectional area along the conductor may improve the current lead performance. The effects of this area change are examined in detail

  14. High-temperature superconducting current leads

    Hull, J. R.

    1992-07-01

    The use of high-temperature superconductors (HTSs) for current leads to deliver power to devices at liquid helium temperature is near commercial realization. The use of HTSs in this application has the potential to reduce refrigeration requirements and helium boiloff to values significantly lower than the theoretical best achievable with conventional leads. Considerable advantage is achieved by operating these leads with an intermediate temperature heat sink. The HTS part of the lead can be made from pressed and sintered powder. Powder-in-tube fabrication is also possible, however, the normal metal part of the lead acts as a thermal short and cannot provide much stabilization without increasing the refrigeration required. Lead stability favors designs with low current density. Such leads can be manufactured with today's technology, and lower refrigeration results from the same allowable burnout time. Higher current densities result in lower boiloff for the same lead length, but bumout times can be very short. In comparing experiment to theory, the density of helium vapor needs to be accounted for in calculating the expected boiloff. For very low-loss leads, two-dimensional heat transfer and the state of the dewar near the leads may play a dominant role in lead performance.

  15. Quench testing of HTS sub-elements for 13 kA and 600 A leads designed to the specifications for the CERN Large Hadron Collider project

    Cowey, L; Krischel, D; Bock, J J

    2000-01-01

    Ability to safely withstand and survive self quench conditions is an important consideration in the design and utilisation of HTS current leads. The provision of a non superconducting shunt path allows current to be diverted in the event of a transition to the normal state. This shunt should allow very rapid transfer of current out of the HTS material and be able to safely support the full load current for the time required to detect the fault and reduce the current to zero. However, the shunt should also be designed to minimise the increased heat load which will result from it's addition to the lead. Test of leads based on melt cast BSCCO 2212 utilising a fully integrated silver gold alloy sheath are described. The HTS sub- elements form part of a full 13 kA lead, designed to the specifications of CERN for the LHC project. The sub-elements proved able to fully comply with and exceed the quench performance required by CERN. The HTS module was quenched at the full design current and continued to maintain this ...

  16. Bi2212 HTS Tubular Bulk with Conical Shape for Current Lead

    Tamura, H; Mito, T; Yamada, Y; Watanabe, M; Ohkubo, J; Heller, R

    2006-01-01

    Current leads using HTS material have been developed for application in a large scale superconducting magnet system. Tokai University and NIFS have developed Bi2212 tubular bulk which was prepared by a diffusion process. 8 kA of maximum transport current was achieved by a tubular bulk with a cylindrical shape. The maximum current was estimated to be 2 kA at 50 K for this tubular bulk. A current lead can be designed with this bulk the warm end of the HTS part being at 50 K and the cold end at 4.2 K. Under this condition, the cross section of the cold end of the bulk can be reduced. This type of HTS bulk has a great potential for flexible design since the Bi2212 layer can be reacted on the surface of any shapes of substrate. If a conical shaped HTS bulk was made, it could be an advantage for heat leakage to the cold end. To confirm this effect, we have made two types of conical bulk. The transport current of the specimen exceeds 7 kA at 4.2 K and 4 kA of stable current flow was achieved with a warm end temperature of 50 K

  17. Current practice in transvenous lead extraction

    Bongiorni, Maria Grazia; Blomström-Lundqvist, Carina; Kennergren, Charles

    2012-01-01

    AIM: Current practice with regard to transvenous lead extraction among European implanting centres was analysed by this survey. METHODS AND RESULTS: Among all contacted centres, 164, from 30 countries, declared that they perform transvenous lead extraction and answered 58 questions...... with a compliance rate of 99.9%. Data from the survey show that there seems to be an overall increasing experience of managing various techniques of lead extraction and a widespread involvement of cardiac centres in this treatment. Results and complication rates seem comparable with those of main international...... registries. CONCLUSION: This survey gives an interesting snapshot of lead extraction in Europe today and gives some clues for future research and prospective European registries....

  18. Qualification of Fin-Type Heat Exchangers for the ITER Current Leads

    Ballarino, A; Bordini, B; Devred, A; Ding, K; Niu, E; Sitko, M; Taylor, T; Yang, Y; Zhou, T

    2015-01-01

    The ITER current leads will transfer large currents of up to 68 kA into the biggest superconducting magnets ever built. Following the development of prototypes and targeted trials of specific manufacturing processes through mock-ups, the ASIPP (Chinese Institute of Plasma Physics) is preparing for the series fabrication. A key component of the ITER HTS current leads are the resistive heat exchangers. Special R&D was conducted for these components at CERN and ASIPP in support of their designs. In particular several mock-ups were built and tested in room temperature gas to measure the dynamic pressure drop and compare to 3D CFD models.

  19. Ka-band Doppler Scatterometer for Measurements of Ocean Vector Winds and Surface Currents

    National Aeronautics and Space Administration — Ocean surface currents impact heat transport, surface momentum and gas fluxes, ocean productivity and marine biological communities. Ocean currents also have social...

  20. Design, Assembly, and Commissioning of a Cryogenic DC Current Transformer Designed for Measuring Currents of up to 80 kA

    Montenero, G; Bottura, L; Arpaia, P

    2015-01-01

    A new cryogenic dc current transformer (Cryo-DCCT) has recently been designed and assembled at CERN. The device, whose design is based on that of a high-accuracy 600 A market solution suitable for room temperature applications, is optimized for measuring currents of up to 80 kA and for operation at 4.2 K. The CryoDCCT has been conceived with the objective of preserving the metrological performance of the original commercial device in the new extended range of operation. For reducing the effect of interfering magnetic fields arising from test conditions, it incorporates ferromagnetic and MgB2 superconducting shields. In this paper, the design of the CryoDCCT and the results of the commissioning of the device at CERN are reported. The effectiveness of the current transducer is analysed and discussed. This new device will be used for measuring the secondary current of a 80 kA superconducting transformer feeding a sample of NbSn3 cable at the Facility for Research on Superconducting Cables (FRESCA) at CERN.

  1. 4-13 kA DC current transducers enabling accurate in-situ calibration for a new particle accelerator project, LHC

    Hudson, G

    2005-01-01

    CERN's next generation particle accelerator, the large hadron collider (LHC) requires accurate current measurement up to 13 kA to enable current tracking between individual power converters. DC current transducers (DCCTs) have been developed to allow in-situ calibrations to 10/sup -6/ uncertainty. This paper describes the principle, design and initial evaluations.

  2. New 30 kA power system at Fermilab and its use for measuring the effects of ripple current on the performance of superconducting high field magnets

    Carcagno, R.; Feher, S.; Garvey, J.; Jaskierny, W.; Lamm, M.; Makulski, A.; Orris, D.F.; Pfeffer, H.; Tartaglia, M.; Tompkins, J.; Wolff, D.; /Fermilab

    2004-12-01

    A new 30 kA, 30 V dc Power System was designed, built, and commissioned at Fermilab for testing Superconducting High Field Magnets. This system has been successfully supporting operations at the Fermilab Magnet Test Facility since April 2002. It is based on six commercial 150 kW Power Energy Industries power supply modules and the following in-house modules: six 720 Hz filters, two 15 kA/1kV dc solid-state dump switch, and a 3 MJ/30 kA/1 kV dc dump resistor. Additional inhouse electronic components were designed and built to provide precise current regulation and distribution of current and current rate of change. An industrial-type Programmable Logic Controller system was used to provide equipment interlocks and monitoring. This paper summarizes studies on the influence of characteristics of this new power system--such as ripple current--on the performance of High Field Superconducting magnets.

  3. Aging characteristics of blue InGaN micro-light emitting diodes at an extremely high current density of 3.5 kA cm−2

    Tian, Pengfei; Liu, Ran; Althumali, Ahmad; Gu, Erdan; Watson, Ian M; Dawson, Martin D

    2016-01-01

    The aging characteristics of blue InGaN micro-light emitting diodes (micro-LEDs) with different sizes have been studied at an extremely high current density 3.5 kA cm −2 for emerging micro-LED applications including visible light communication (VLC), micro-LED pumped organic lasers and optogenetics. The light output power of micro-LEDs first increases and then decreases due to the competition of Mg activation in p-GaN layer and defect generation in the active region. The smaller micro-LEDs show less light output power degradation compared with larger micro-LEDs, which is attributed to the lower junction temperature of smaller micro-LEDs. It is found that the high current density without additional junction temperature cannot induce significant micro-LED degradation at room temperature but the combination of the high current density and high junction temperature leads to strong degradation. Furthermore, the cluster LEDs, composed of a micro-LED array, have been developed with both high light output power and less light output degradation for micro-LED applications in solid state lighting and VLC. (paper)

  4. Design and application consideration of high temperature superconducting current leads

    Wu, J.L.

    1994-01-01

    As a potential major source of heat leak and the resultant cryogen boiloff, cryogenic current leads can significantly affect the refrigeration power requirement of cryogenic power equipment. Reduction of the heat leak associated with current leads can therefore contribute to the development and application of this equipment. Recent studies and tests have demonstrated that, due to their superconducting and low thermal conductivity properties, ceramic high temperature superconductor (HTSC) can be employed in current leads to significantly reduce the heat leak. However, realization of this benefit requires special design considerations pertaining to the properties and the fabrication technology of the relatively new ceramic superconductor materials. Since processing and fabrication technology are continuously being developed in the laboratories, data on material properties unrelated to critical states are quite limited. Therefore, design analysis and experiments have to be conducted in tandem to achieve a successful development. Due to the rather unique combination of superconducting and thermal conductivities which are orders of magnitude lower than copper, ceramic superconductors allow expansion of the operating scenarios of current leads. In addition to the conventional vapor-cooled lead type application, low heat leak conduction-cooled type current leads may be practical and are being developed. Furthermore, a current lead with an intermediate heat leak intercept has been successfully demonstrated in a multiple current lead assembly employing HTSC. These design and application considerations of high temperature superconducting current leads are addressed here

  5. 1-D thermal-hydraulic analysis of the high temperature superconducting current leads for the ITER magnet system from 5 K to 300 K

    Rizzo, Enrico, E-mail: enrico.rizzo@kit.edu [Institute for Technical Physics, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen (Germany); Bauer, Pierre [ITER Organization, Cadarache (France); Heller, Reinhard [Institute for Technical Physics, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen (Germany); Richard, Laura Savoldi; Zanino, Roberto [Dipartimento Energia, Politecnico di Torino, 10129 Torino (Italy)

    2013-12-15

    Highlights: • A global, predictive picture of the ITER HTS current lead is not yet available. • A predictive 1-D, steady state thermal-hydraulic analysis of the full length HTS current leads has been performed. • For the heat exchanger, correlations previously derived by the same authors have been used. • The results have been compared with the ITER relevant requirements. • According to our results, the ITER HTS current leads will fulfill the requirements. -- Abstract: The magnet system of ITER includes high temperature superconducting (HTS) current leads with a maximum current of 68 kA for the toroidal field (TF) coils, 55 kA for the poloidal field (PF)/central solenoid (CS) coils and 10 kA for the control coils (CC), respectively. Although different in terms of size and operative conditions, the ITER HTS current leads have been all designed on the basis of an established concept, which was successfully developed for the LHC at CERN and proven by the so-called 70 kA “demonstrator” lead made by KIT and by the ITER pre-prototypes made by ASIPP in China. A broad R and D campaign has been undertaken by ASIPP and CERN in order to find optimized designs for each component of the leads. Nevertheless, a comprehensive picture of the performance of the entire HTS current leads is not yet available. In this paper, a steady state, full length, thermal-hydraulic 1-D modeling is applied to the study of the three types (TF, PF/CS, CC) of ITER HTS current leads. The results of this predictive analysis are then compared with relevant ITER requirements. It was found that the present design of the HTS current leads will fulfill these specifications.

  6. New 30 kA power system at Fermilab and its use for measuring the effects of ripple current on the performance of superconducting high field magnets

    Carcagno, R.; Feher, S.; Garvey, J.; Jaskierny, W.; Lamm, M.; Makulski, A.; Orris, D.F.; Pfeffer, H.; Tartaglia, M.; Tompkins, J.; Wolff, D.

    2004-01-01

    A new 30 kA, 30 V dc Power System was designed, built, and commissioned at Fermilab for testing Superconducting High Field Magnets. This system has been successfully supporting operations at the Fermilab Magnet Test Facility since April 2002. It is based on six commercial 150 kW Power Energy Industries power supply modules and the following in-house modules: six 720 Hz filters, two 15 kA/1kV dc solid-state dump switch, and a 3 MJ/30 kA/1 kV dc dump resistor. Additional in-house electronic components were designed and built to provide precise current regulation and distribution of current and current rate of change. An industrial-type Programmable Logic Controller system was used to provide equipment interlocks and monitoring. This paper summarizes studies on the influence of characteristics of this new power system--such as ripple current--on the performance of High Field Superconducting Magnets

  7. Quench propagation in High Temperature Superconducting materials integrated in high current leads

    Milani, D

    2001-01-01

    High temperature superconductors (HTS) have been integrated in the high current leads for the Large Hadron Collider (LHC), under construction at CERN, in order to reduce the heat leak into the liquid helium bath due to the joule effect. The use of the HTS technology in the lower part of the current leads allowed to significantly reduce the heat charge on the cryogenic system. Hybrid current leads have been designed to fulfill the LHC requirements with respect to thermal load; several tests have been performed to study the lead behavior especially during a quench transient. Quench experiments have been performed at CERN on 13 kA prototypes to determine the adequate design and protection. In all the tests it is possible to know the temperature profile of the HTS only with the help of quench simulations that model the thermo-hydraulic processes during quench. The development of a theoretical model for the simulation allows reducing the number of test to perform and to scale the experimental result to other curre...

  8. 600 a Current Leads with Dry and Compact Warm Terminals

    Andersen, T P; Vullierme, B

    2002-01-01

    For the LHC magnet test benches 26 pairs of conventional helium vapour-cooled 600 A current leads are required. The first pair of 600 A current leads has been designed and built by industry and tested at CERN. The main component of the lead is the heat exchanger, which consists of two concentric copper pipes. Special attention was also given to the design of the warm terminal in order to avoid any condensation and to resist at an electrical test of 2 kV. The paper describes construction details and compares calculated and measured values of the main parameters.

  9. Current practices in generation of small molecule new leads.

    Goodnow, R A

    2001-01-01

    The current drug discovery processes in many pharmaceutical companies require large and growing collections of high quality lead structures for use in high throughput screening assays. Collections of small molecules with diverse structures and "drug-like" properties have, in the past, been acquired by several means: by archive of previous internal lead optimization efforts, by purchase from compound vendors, and by union of separate collections following company mergers. More recently, many drug discovery companies have established dedicated efforts to effect synthesis by internal and/or outsourcing efforts of targeted compound libraries for new lead generation. Although high throughput/combinatorial chemistry is an important component in the process of new lead generation, the selection of library designs for synthesis and the subsequent design of library members has evolved to a new level of challenge and importance. The potential benefits of screening multiple small molecule compound library designs against multiple biological targets offers substantial opportunity to discover new lead structures. Subsequent optimization of such compounds is often accelerated because of the structure-activity relationship (SAR) information encoded in these lead generation libraries. Lead optimization is often facilitated due to the ready applicability of high-throughput chemistry (HTC) methods for follow-up synthesis. Some of the strategies, trends, and critical issues central to the success of lead generation processes are discussed below. Copyright 2002 Wiley-Liss, Inc.

  10. Testing and evaluation of high temperature superconductor current leads

    Yadav, Anand; Puntambekar, Avinash; Manekar, M.A.

    2009-01-01

    National Institute for Inter-disciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research, Trivandrum (formerly Regional Research Laboratory) has accomplished a DAE-BRNS project with Raja Ramanna Centre for Advanced Technology (RRCAT) as principal collaborator for the development of high temperature superconductor (HTS) current leads. These HTS current leads have self-field critical currents (Ic) ranging from 50 A to 1000 A at liquid nitrogen (LN 2 ) temperature. These HTS are made out of silver sheathed Bismuth Strontium Calcium Copper Oxide (BSCCO-2223), for direct application in superconducting (SC) systems involving transportation of high electric currents from power sources at room temperature to superconducting devices at cryogenic temperatures. RRCAT has participated in this project by testing and evaluation of these HTS current leads and carried out actual load trials. In this paper, we will describe the HTS testing setup, tests performed with their testing procedure and the test results. The testing of these HTS has been done with joint effort of Materials Advanced Accelerator Science and Cryogenics Div. and Superconducting Technology Lab (SCT Lab), Advanced Accelerator Module Development Div., using the test facility available at the SCT Lab. (author)

  11. Comparison of different current transducers used at JET within the range 5–100 kA for plasma control and monitoring

    Salmon, R., E-mail: robjsalmon@gmail.com; Smith, P.; West, A.; Shaw, S.R.; Rendell, D.

    2015-10-15

    Highlights: • Zero-flux current transducers with sensory windings, Hall-effect DCCTs, Rogowski coils, shunt resistors and Faraday effect current transducers are reviewed. • All technologies have displayed good performance over 30 years of operation. • Faraday-effect current transducers have improved accuracy of the toroidal magnets current measurement on JET to 0.1%. • The improvement in accuracy has improved resolution on JET plasma kinetic profiles. - Abstract: The JET machine uses a variety of current transducers for control and protection of the plasma, the coils and their associated power supplies. This paper reviews the various measuring technologies, within the range 5–100 kA, used on JET to assist with the selection of high-current transducers for future plasma control/tokamak applications; these include Rogowski coils, coaxial shunts, Hall-effect transducers, zero-flux CTs and a Faraday-effect optical transducer. The paper considers reliability, accuracy and usability based on up to 30 years of operational experience of the transducers. Accuracy of the magnet current measurements is important in the control of tokamak plasmas and there has been considerable effort to improve it. Recently a Faraday-effect optical current sensor has been used to measure up to 67 kA in the Toroidal Field (TF) coil circuit. This measurement system has been calibrated at JET to verify its 0.1% accuracy. In addition, the data acquisition system for this measurement is automatically calibrated at the start of each JET pulse. The improved accuracy has been shown to enhance the spatial consistency of kinetic profiles at JET [1]. Due to its portability the JET project intends to employ the same Faraday-effect current transducer to calibrate other high current transducers by temporarily fitting it to other busbars, such as those in the Ohmic Heating network.

  12. Updating and test on 12 kA HTSCL for Russia JINR

    Zhou, Tingzhi; Ding, K; Liu, C; Xu, C; Feng, H; Wu, H; Liu, X; Song, Y

    2014-01-01

    The Joint Institute for Nuclear Research (JINR) started manufacture and test of superconducting magnets for the new accelerator complex Nuclotron-based Ion Collider fAcility (NICA). A pair of current leads rated 12 kA was developed for cold testing of the magnets in 2012. The operation of the facility needs ∼350 leads rated from 100 A to 12 kA to convey current for the magnets. After the test of the pair of 12 kA leads in JINR a contract of supplying 3 pairs of 12 kA high temperature superconducting current leads (HTSCLs) were signed to ASIPP this year. In this paper the design updating and test of the current leads are introduced.

  13. Engineering design of a high-temperature superconductor current lead

    Niemann, R.C.; Cha, Y.S.; Hull, J.R.; Daugherty, M.A.; Buckles, W.E.

    1993-01-01

    As part of the US Department of Energy's Superconductivity Pilot Center Program, Argonne National Laboratory and Superconductivity, Inc., are developing high-temperature superconductor (HTS) current leads suitable for application to superconducting magnetic energy storage systems. The principal objective of the development program is to design, construct, and evaluate the performance of HTS current leads suitable for near-term applications. Supporting objectives are to (1) develop performance criteria; (2) develop a detailed design; (3) analyze performance; (4) gain manufacturing experience in the areas of materials and components procurement, fabrication and assembly, quality assurance, and cost; (5) measure performance of critical components and the overall assembly; (6) identify design uncertainties and develop a program for their study; and (7) develop application-acceptance criteria

  14. Engineering design of a high-temperature superconductor current lead

    Niemann, R. C.; Cha, Y. S.; Hull, J. R.; Daugherty, M. A.; Buckles, W. E.

    As part of the US Department of Energy's Superconductivity Pilot Center Program, Argonne National Laboratory and Superconductivity, Inc., are developing high-temperature superconductor (HTS) current leads suitable for application to superconducting magnetic energy storage systems. The principal objective of the development program is to design, construct, and evaluate the performance of HTS current leads suitable for near-term applications. Supporting objectives are to (1) develop performance criteria; (2) develop a detailed design; (3) analyze performance; (4) gain manufacturing experience in the areas of materials and components procurement, fabrication and assembly, quality assurance, and cost; (5) measure performance of critical components and the overall assembly; (6) identify design uncertainties and develop a program for their study; and (7) develop application-acceptance criteria.

  15. Characterization of high-current, high-temperature superconductor current lead elements

    Niemann, R.C.; Evans, D.J.; Fisher, B.L.; Brockenborough, W.E.; Roberts, P.R.; Rodenbush, A.J.

    1996-08-01

    The refrigeration loads of current leads for superconducting magnets can be significantly reduced by using high-temperature superconductor (HTS) leads. An HTS conductor type that is well suited for this application is a laminated sintered stack of HTS powder-in-tube (PIT) tapes. The superconducting elements are normally characterized by their manufacturer by measuring critical currents at 77 K in self field. Additional characterization, which correlates electrical performance at 77 K and at lower temperatures with applied magnetic fields, provides the current lead designer and conductor element manufacturer with critical information. For HTS conductor elements comprising a laminated and sintered stack of Bi-2223 PIT tapes having an alloyed Ag sheath, this characterization uses variable applied fields and operating temperatures

  16. Current perspectives in fragment-based lead discovery (FBLD)

    Lamoree, Bas; Hubbard, Roderick E.

    2017-01-01

    It is over 20 years since the first fragment-based discovery projects were disclosed. The methods are now mature for most ‘conventional’ targets in drug discovery such as enzymes (kinases and proteases) but there has also been growing success on more challenging targets, such as disruption of protein–protein interactions. The main application is to identify tractable chemical startpoints that non-covalently modulate the activity of a biological molecule. In this essay, we overview current practice in the methods and discuss how they have had an impact in lead discovery – generating a large number of fragment-derived compounds that are in clinical trials and two medicines treating patients. In addition, we discuss some of the more recent applications of the methods in chemical biology – providing chemical tools to investigate biological molecules, mechanisms and systems. PMID:29118093

  17. Critical reflections on the currently leading definition of sustainable employability.

    Fleuren, Bram Bi; de Grip, Andries; Jansen, Nicole Wh; Kant, Imjert; Zijlstra, Fred Rh

    2016-06-01

    Sustainable employability (SE) is an important topic as it deals with employees' abilities to function adequately at work and in the labor market throughout their working lives. However, until now there has been only one attempt to define SE in the international literature (1). This first definition is a valuable contribution to the field as it rightfully describes SE as a multidimensional concept, recognizes the importance of both employee and work characteristics, and acknowledges the inherently longitudinal nature of SE. Despite these merits, we argue that this definition of SE has some serious omissions that are important in capturing SE comprehensively. Specifically, we argue that the definition could be improved in various ways, namely, it should: (i) clarify which aspects of employment constitute someone's SE; (ii) not counterintuitively treat SE as a characteristic of both the job and the employee simultaneously; (iii) not be based on the insufficiently tested assumption that achieving value in work inherently leads to SE; (iv) be formulated in a way that SE can also apply to unemployed individuals; and (v) adequately specify how the inherently longitudinal dimension of SE should be addressed. We would like to contribute to the discussion by providing guidelines for a new adjusted definition of SE that could facilitate further research on this important concept and its determinants. Introduction SE is a topic of vital importance to individual employees, organizations and society alike. It generally refers to employees' capacities to function in work throughout their working life. As participation in work is important for individuals, organizations, and society as a whole, individuals' ability to function in work is essential. For individuals, work provides meaning, financial security as well as social contacts. Organizations need productive employees to survive. Also from a societal perspective, it is important that as many people as possible participate in

  18. Occurrence of lead-related symptoms below the current occupational safety and health act allowable blood lead levels.

    Rosenman, Kenneth D; Sims, Amy; Luo, Zhehui; Gardiner, Joseph

    2003-05-01

    To determine the occurrence of symptoms of lead toxicity at levels below the current allowable Occupational Safety and Health Act blood lead level of 50 micrograms/dL, standardized telephone interviews were conducted of individuals reported to a statewide laboratory-based surveillance system. Four hundred and ninety-seven, or 75%, of the eligible participants were interviewed. Gastrointestinal, musculoskeletal, and nervous system symptoms increased with increasing blood lead levels. Nervous, gastrointestinal, and musculoskeletal symptoms all began to be increased in individuals with blood leads between 30-39 micrograms/dL and possibly at levels as low as 25-30 micrograms/dL for nervous system symptoms. The results of this study of increased symptoms are consistent with and provide added weight to previous results showing subclinical changes in the neurologic and renal systems and sperm counts at blood lead levels currently allowed by the Occupational Safety and Health Act.

  19. Development of a multiple HTS current lead assembly for corrector magnets application

    Wu, J.L.; Dederer, J.T.; Singh, S.K.

    1994-01-01

    Vapor-cooled current leads used for transmitting power to superconducting power equipment such as the corrector magnets in the SSC spools can introduce a significant heat leak into the cryostat which results in cryogen boil-off. Replenishing the boil-off or refrigerating and liquefying the vapors associated with the cooling of these leads may constitute a significant portion of the operating cost and/or the capital investment of the power equipment. Theoretical studies and experiments have demonstrated that the heat leak introduced by a current lead can be significantly reduced by using ceramic high temperature superconductor (HTSC) as part of the conductor in the current leads. A HTSC reduces heat leak in a current lead by being superconducting in the temperature range below its critical temperature and by having a low temperature thermal conductivity which is generally orders of magnitude lower than the copper alloys commonly used as the current lead conductors. This combination reduces Joule heating and heat conduction, resulting in lower heat leak to the cryostat. To demonstrate the advantages and large scale application of this technology, Westinghouse Science ampersand Technology Center has continued its efforts in High Temperature Superconducting (HTS) current lead development. The efforts include qualification testing and selection of commercial sources of HTSC for current leads and the successful development of a 12 x 100 A multiple HTS current lead assembly prototype for SSC Corrector Element Power Lead application. The efforts on the design, fabrication and testing of the multiple HTS lead assembly is reported below

  20. Ultra-Low Heat-Leak, High-Temperature Superconducting Current Leads for Space Applications

    Rey, Christopher M.

    2013-01-01

    NASA Goddard Space Flight Center has a need for current leads used in an adiabatic demagnetization refrigerator (ADR) for space applications. These leads must comply with stringent requirements such as a heat leak of approximately 100 W or less while conducting up to 10 A of electric current, from more than 90 K down to 10 K. Additionally, a length constraint of leak leads currently to NASA's specs.

  1. Criterion for burn-up conditions in gas-cooled cryogenic current leads

    Bejan, A.; Cluss, E.M. Jr.

    1976-01-01

    Superconducting magnets are energized through helium vapour-cooled cryogenic current leads operating at high ratios of current to mass flow. The high current operation where lead temperature, runaway, and eventual burn-up are likely to occur is investigated. A simple criterion for estimating the burn-up operation conditions (current, mass flow) for a given lead geometry (cross-sectional area, length, heat exchanger area) is presented. This article stresses the role played by the available heat exchanger area in avoiding burn-up at high ratios of current to mass flow. (author)

  2. Kuulus dress ka Evelinile!

    2009-01-01

    Proua Evelin Ilves kinkis Eestis esinenud popstaar Madonnale eesti rahvusmotiividega dressid. Sarnased spordirõivad tulevad müügile ka Tallinnas Viru keskuses Bastioni esinduskaupluses. Proua Evelin Ilvesele valmistatakse ainulaadsed valgest kangast dressid

  3. Performance of bismuth tape current leads under vibration; Bi tepu sei denryu rido no shindo tokusei

    Suzuki, E.; Kurihara, M. [Railway Techniical Research Institute, Tokyo (Japan)

    2000-02-25

    The superconducting magnets on Maglev vehicles when running vibrate mechanically due to electromagnetic disturbance from the ground coils. Therefore, the current leads fixed on the superconducting coil, which is vibration at about 98 m/s{sup 2} (=10g), are also required to endure the vibration. We executed dynamic vibration tests for two types of current leads (straight and arc types) which had a multi-stacked configuration of Ag-sheathed Bi2223 tapes impregnated with epoxy resin in a concaved reinforcing gutter. We evaluated the straight-type lead for an operating current of 700 A after every vibration test in liquid nitrogen for one hour under the dynamic strain deformation of 50-100 {mu} on the surface of the reinforcing material covering the current lead. We could not detect degradation of the current lead by vibration through the total cycles of 3.9 x 10{sup 6} after continuous vibration tests. We also executed vibration tests for arc-type current leads which were combined with an actual energized superconducting coil for a Maglev. Large accelerations of these current leads occurred at frequencies of 308 and 375 Hz. In spite of the maximum acceleration of 600-700 m/s{sup 2} generated by actuating the excessive force on a superconducting coil for two seconds, which occurred on these current leads carrying 500 A, the superconductivity of the current leads did not shift to normal conductivity. There was no damage to either type of current lead during these vibration tests. So we confirmed the good prospect for the application of these current leads to actual Maglev superconducting magnets. (author)

  4. High temperature superconducting current lead test facility with heat pipe intercepts

    Blumenfeld, P.E.; Prenger, C.; Roth, E.W.; Stewart, J.A.

    1998-01-01

    A high temperature superconducting (HTS) current lead test facility using heat pipe thermal intercepts is under development at the Superconducting Technology Center at Los Alamos National Laboratory. The facility can be configured for tests at currents up to 1,000 A. Mechanical cryocoolers provide refrigeration to the leads. Electrical isolation is maintained by intercepting thermal energy from the leads through cryogenic heat pipes. HST lead warm end temperature is variable from 65 K to over 90 K by controlling heat pipe evaporator temperature. Cold end temperature is variable up to 30 K. Performance predictions in terms of heat pipe evaporator temperature as a function of lead current are presented for the initial facility configuration, which supports testing up to 200 A. Measurements are to include temperature and voltage gradient in the conventional and HTS lead sections, temperature and heat transfer rate in the heat pipes. as well as optimum and off-optimum performance of the conventional lead sections

  5. Thermal conductivity measurement of HTS tapes and stacks for current lead applications

    Schwarz, Michael; Weiss, Klaus-Peter; Heller, Reinhard; Fietz, Walter H.

    2009-01-01

    The use of high-temperature-superconductors (HTS) within current leads offers a high potential to save cooling-power. The principle of HTS current leads is well established, e.g. for particle accelerators (LHC-CERN) but also on the commercial sector, which offer HTS current leads ready for use in small scale magnets and magnets systems. Future fusion machines currently under construction like ITER, W7-X or JT-60SA also will use HTS current leads. At the moment the standard material for HTS current leads is a Bi 2 Sr 2 Ca 2 Cu 3 O x (BSCCO)-AgAu composite tape. The common way to receive high current capacity current leads is to form stacks by sintering or soldering these tapes together. The solder changes the thermal conductivity of the stacks compared to the single tape in the temperature range from 4 K to 60 K. To estimate the heat flux from the warm environment to the cold application the measurement of the thermal conductivity of the soldered stack is mandatory. Therefore the thermal conductivity of stacks with different number of tapes is investigated. To measure the thermal conduction in the current flow direction, the axial heat flow method is used. Combining these results with FEM simulations gives the possibility to estimate the thermal conductivity normal to the flat tape plane. The resulting anisotropic thermal conductivity can be used to model the behaviour of the HTS tape under thermal disturbances more accurately.

  6. Conceptual design of current lead for large scale high temperature superconducting rotating machine

    Le, T. D.; Kim, J. H.; Park, S. I.; Kim, H. M.

    2014-01-01

    High-temperature superconducting (HTS) rotating machines always require an electric current of from several hundreds to several thousand amperes to be led from outside into cold region of the field coil. Heat losses through the current leads then assume tremendous importance. Consequently, it is necessary to acquire optimal design for the leads which would achieve minimum heat loss during operation of machines for a given electrical current. In this paper, conduction cooled current lead type of 10 MW-Class HTS rotating machine will be chosen, a conceptual design will be discussed and performed relied on the least heat lost estimation between conventional metal lead and partially HTS lead. In addition, steady-state thermal characteristic of each one also is considered and illustrated.

  7. Design of a high-temperature superconductor current lead for electric utility SMES

    Niemann, R.C.; Cha, Y.S.; Hull, J.R.; Rey, C.M.; Dixon, K.D.

    1995-01-01

    Current leads that rely on high-temperature superconductors (HTSs) to deliver power to devices operating at liquid helium temperature have the potential to reduce refrigeration requirements to levels significantly below those achievable with conventional leads. The design of HTS current leads suitable for use in near-term superconducting magnetic energy storage (SMES) is in progress. The SMES system has an 0.5 MWh energy capacity and a discharge power of 30 MW. Lead-design considerations include safety and reliability, electrical and thermal performance, structural integrity, manufacturability, and cost. Available details of the design, including materials, configuration, and performance predictions, are presented

  8. Prediction of burnout of a conduction-cooled BSCCO current lead

    Seol, S.Y.; Cha, Y.S.; Niemann, R.C.; Hull, J.R.

    1996-01-01

    A one-dimensional heat conduction model is employed to predict burnout of a Bi 2 Sr 2 CaCu 2 O 8 current lead. The upper end of the lead is assumed to be at 77 K and the lower end is at 4 K. The results show that burnout always occurs at the warmer end of the lead. The lead reaches its burnout temperature in two distinct stage. Initially, the temperature rises slowly when part of the lead is in flux-flow state. As the local temperature reaches the critical temperature, it begins to increase sharply. Burnout time depends strongly on flux-flow resistivity

  9. HTS current lead units prepared by the TFA-MOD processed YBCO coated conductors

    Shiohara, K.; Sakai, S.; Ishii, Y.; Yamada, Y.; Tachikawa, K.; Koizumi, T.; Aoki, Y.; Hasegawa, T.; Tamura, H.; Mito, T.

    2010-01-01

    Two superconducting current lead units have been prepared using ten coated conductors of the Tri-Fluoro-Acetate - Metal Organic Deposition (TFA-MOD) processed Y 1 Ba 2 Cu 3 O 7-δ (YBCO) coated conductors with critical current (I c ) of about 170 A at 77 K in self-field. The coated conductors are 5 mm in width, 190 mm in length and about 120 μm in overall thickness. The 1.5 μm thick superconducting YBCO layer was synthesized through the TFA-MOD process on Hastelloy TM C-276 substrate tape with two buffer oxide layers of Gd 2 Zr 2 O 7 and CeO 2 . The five YBCO coated conductors are attached on a 1 mm thick Glass Fiber Reinforced Plastics (GFRP) board and soldered to Cu caps at the both ends. We prepared two 500 A-class current lead units. The DC transport current of 800 A was stably applied at 77 K without any voltage generation in all coated conductors. The voltage between both Cu caps linearly increased with increasing the applied current, and was about 350 μV at 500 A in both current lead units. According to the estimated values of the heat leakage from 77 K to 4.2 K, the heat leakage for the current lead unit was 46.5 mW. We successfully attained reduction of the heat leakage because of improvement of the transport current performance (I c ), a thinner Ag layer of YBCO coated conductor and usage of the GFRP board for reinforcement instead of a stainless steel board used in the previous study. The DC transport current of 1400 A was stably applied when the two current lead units were joined in parallel. The sum of the heat leakages from 77 K to 4.2 K for the combined the current lead units was 93 mW. In comparison with the conventional Cu current leads by gas-cooling, it could be noted that the heat leakage of the current lead is about one order of magnitude smaller than that of the Cu current lead.

  10. Reduction of the heat leak in superconducting system at half-wave-rectified current mode by peltier current lead

    Yamaguchi, Takayuki; Ohtaki, Naohiro; Nakamura, Keiji; Yamaguchi, Satarou; Hasegawa, Yasuhiro

    2002-01-01

    Experiments of Peltier current lead (PCL) were performed by the way of half-wave-rectified current (HWRC) for an evaluation of the PCL system in the drive with the large-rippled current. The current ripple of the HWRC is large, and we discussed the cooling capability of the current ripple. The experimental results revealed that the temperature difference of the thermoelectric-element (TE) increased with the magnitude of the current in the PCL system, despite the large current ripple. Calorimetric measurements revealed that the PCL reduced the heat leak of 60% for the peak current 90A. We compared the PCL systems of the direct current (dc) mode and the HWRC mode. The results showed that the current dependence of the temperature difference in the HWRC mode did not match that of the dc mode, but those of the heat leak matched well. The performance of the Peltier cooling in the HWRC mode is reduced to be 2/π time of the Seebeck coefficient for the dc mode by using the time-average method. (author)

  11. Reduction of the heat leak in superconducting system at half-wave-rectified current mode by peltier current lead

    Yamaguchi, T; Nakamura, K; Yamaguchi, S; Hasegawa, Y

    2002-01-01

    Experiments of Peltier current lead (PCL) were performed by the way of half-wave-rectified current (HWRC) for an evaluation of the PCL system in the drive with the large-rippled current. The current ripple of the HWRC is large, and we discussed the cooling capability of the current ripple. The experimental results revealed that the temperature difference of the thermoelectric-element (TE) increased with the magnitude of the current in the PCL system, despite the large current ripple. Calorimetric measurements revealed that the PCL reduced the heat leak of 60% for the peak current 90A. We compared the PCL systems of the direct current (dc) mode and the HWRC mode. The results showed that the current dependence of the temperature difference in the HWRC mode did not match that of the dc mode, but those of the heat leak matched well. The performance of the Peltier cooling in the HWRC mode is reduced to be 2/pi time of the Seebeck coefficient for the dc mode by using the time-average method. (author)

  12. Tevatron HTS power lead test

    Feher, S.; Carcagno, R.; Orris, D.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.; Tompkins, J.C.

    2004-01-01

    Two pairs of ASC 6 kA power leads developed for the Tevatron were successfully tested at Fermilab at over-current conditions. Stable operation was achieved while operating at a current of 9.56 kA for five hours and while continuously ramping between 0-9.56 kA at a ramp rate of 200 A/s for one hour. The minimum required liquid nitrogen flow rate was measured to be 1.5 g/s at 10 kA. After ramping up to 10 kA at 200A/s, it took only 15 minutes to stabilize the upper copper section of the lead with a flow of 1.8 g/s of liquid nitrogen vapor. Testing under extreme operating conditions--270-370 kPa liquid nitrogen vapor pressure and over 0.1 T external magnetic field--demonstrated that the HTS part of the lead can safely operate in the current sharing mode and that this design has large operating margin

  13. Full Cryogenic Test of 600 A HTS Hybrid Current Leads for the LHC

    Al-Mosawi, MK; Beduz, C; Ballarino, A; Yang, Y

    2007-01-01

    For full cryogenic test of CERN 600 A High Temperature Superconducting (HTS) current leads prior to integration into the Large Hadron Collider (LHC), a ded. facility has been designed, constructed and operated at the University of Southampton. The facility consists of purpose-built test cryostats, 20 K helium gas supply, helium gas flow and temperature control systems and quench protection system. Over 400 such leads have already been successfully tested and qualified for installation at CERN. This paper describes various design and operation aspects of the test facility and presents the detailed cryogenic test results of the CERN 600 A current leads, including steady state 20 K flow rates.

  14. Transient characteristics of current lead losses for the large scale high-temperature superconducting rotating machine

    Le, T. D.; Kim, J. H.; Park, S. I.; Kim, D. J.; Kim, H. M.; Lee, H. G.; Yoon, Y. S.; Jo, Y. S.; Yoon, K. Y.

    2014-01-01

    To minimize most heat loss of current lead for high-temperature superconducting (HTS) rotating machine, the choice of conductor properties and lead geometry - such as length, cross section, and cooling surface area - are one of the various significant factors must be selected. Therefore, an optimal lead for large scale of HTS rotating machine has presented before. Not let up with these trends, this paper continues to improve of diminishing heat loss for HTS part according to different model. It also determines the simplification conditions for an evaluation of the main flux flow loss and eddy current loss transient characteristics during charging and discharging period.

  15. Experimental study of gas-cooled current leads for superconducting magnets

    Warren, R.P.

    1978-04-01

    Design details and experimental test results from several design variations of the gas-cooled, copper current leads used in conjunction with the superconducting dipole magnets for ESCAR (Experimental Superconducting Accelerator Ring) are reported. Thermal acoustic oscillations, which were experienced with an initial design, were eliminated in subsequent designs by a reduction of the hydraulic diameter. The occurrence of these oscillations is in general agreement with the stability analysis of Rott but the observed gas flow dependence is not in agreement with some other recently reported results for leads operated supercritical phase coolant. An empirically determined correlation was obtained by plotting lead resistance vs. enthalpy gain of the coolant gas. The resulting family of curves can be reduced to a single line on a plot of effective resistivity vs. the product of current and cross-sectional area divided by the product of the square of the mass flow of the coolant and the lead length. This correlation, which should be applicable to other designs of copper current leads in which ideal heat transfer to the coolant gas is approached, predicts that the enthalpy gain of the coolant, and therefore the peak lead temperature, is proportional to the cube of the ratio of current to coolant mass flow. The effective value of the strongly temperature-dependent kinematic viscosity of the coolant gas was found to vary linearly with the effective resistivity of the lead

  16. Research and development of an aimed magnetic lead current density-magnetic field diagnostic. Final report

    1985-01-01

    A diagnostics survey was made to provide a clear definition of advanced diagnostic needs and the limitations of current approaches in addressing those needs. Special attention was given to the adequacy with which current diagnostics are interfaced to signal processing/data acquisition devices and systems. Critical evaluations of selected alternative diagnostic techniques for future R and D activities are presented. The conceptual basis of the Aimed Magnetic Lead Gradiometric system as a current density/magnetic field diagnostic is established

  17. Survey of current lead use, handling, hygiene, and contaminant controls among New Jersey industries.

    Blando, James D; Lefkowitz, Daniel K; Valiante, David; Gerwel, Barbara; Bresnitz, Eddy

    2007-08-01

    In 2003, a chemical handling and use survey was mailed to New Jersey employers identified as currently using lead in their industrial processes. This survey was used to ascertain characteristics about lead use, handling, and protection of employees during manufacturing operations. The survey included a diverse group of current lead users with a total lead use range from less than 1 pound to more than 63 million pounds of lead per year. The survey allowed for a comprehensive characterization of hazards and protective measures associated with this metal, still commonly used in many products and industrial processes. Forty-five surveys were returned by companies that are listed in the New Jersey Adult Blood Lead Registry, which is part of the New Jersey Adult Blood Lead Epidemiology and Surveillance (ABLES) program. This program records and investigates cases of adults with greater than 25 mu g/dL of lead in their blood; most cases are related to occupational exposures. This survey found that greater than 25% of these surveyed companies with significant potential for lead exposure did not employ commonly used and basic industrial hygiene practices. In addition, the survey found that 24% of these companies had not conducted air sampling within the last 3 years. Air sampling is the primary trigger for compliance with the Occupational Safety and Health Administration (OSHA) general industry lead standard. Only 17% of the companies have ever been cited for a violation of the OSHA lead standard, and only 46% of these companies have ever had an OSHA inspection. State-based surveillance can be a useful tool for OSHA enforcement activities. Elevated blood lead values in adults should be considered as a trigger for required compliance with an OSHA general industry lead standard.

  18. Lead content of dried films of domestic paints currently sold in Nigeria

    Adebamowo, Eugenious O.; Scott Clark, C.; Roda, Sandy; Agbede, Oluwole A.; Sridhar, Mynepalli K.C.; Adebamowo, Clement A.

    2007-01-01

    Children are at higher risk from lead exposure because their developing neural system is susceptible to its neurotoxic effects. We studied lead levels of paints manufactured in Nigeria in 2006. Lead levels in 5 colors of paints, each from different manufacturers were measured using flame-atomic absorption spectroscopy. We found that 96% of the paints had higher than recommended levels of lead. The mean lead level of paints ranged from 84.8 to 50,000 ppm, with mean of 14,500 ppm and median of 15,800 ppm. The main determinant of lead levels was color of the paint. As lead levels in paint sold in the past years in Nigeria are likely to be at least as high as that currently sold, it is likely that many existing houses contain dangerously high levels of lead. Efforts need to be undertaken to assess the presence of high lead levels in existing housing and if detected, intervention programs for eliminating risk of exposure should be developed in addition to measures to increase awareness and enforce regulations leading to the elimination of lead based domestic paint

  19. Conceptual design of cooling anchor for current lead on HTS field coils

    Hyeon, C. J.; Kim, J. H.; Quach, H. L. [Dept. of Electrical Engineering, Jeju National University, Jeju (Korea, Republic of); and others

    2017-06-15

    The role of current lead in high-temperature superconducting synchronous machine (HTSSM) is to function as a power supply by connecting the power supply unit at room temperature with the HTS field coils at cryogenic temperature. Such physical and electrical connection causes conduction and Joule-heating losses, which are major thermal losses of HTSSM rotors. To ensure definite stability and economic feasibility of HTS field coils, quickly and smoothly cooling down the current lead is a key design technology. Therefore, in this paper, we introduce a novel concept of a cooling anchor to enhance the cooling performance of a metal current lead. The technical concept of this technology is the simultaneously chilling and supporting the current lead. First, the structure of the current lead and cooling anchor were conceptually designed for field coils for a 1.5 MW-class HTSSM. Then, the effect of this installation on the thermal characteristics of HTS coils was investigated by 3D finite element analysis.

  20. THREE-ELECTRODE AIR SWITCHBOARD WITH THE GRAPHITE ELECTRODES OF KATG-50 ON VOLTAGE TO ±50 KV AND IMPULSE CURRENT BY AMPLITUDE TO ±220 KA

    M. I. Baranov

    2015-04-01

    Full Text Available Purpose. Development and creation of the simplified construction of a high-voltage heavy-current air three-electrode switchboard with graphite electrodes, intended for operation in composition the powerful generator of large impulsive current of artificial of linear lightning. Methodology. Electrophysics bases of technique of high-voltage and scientific and technical bases of planning of devices of high-voltage impulsive technique. Results. Developed and made a new construction of a high-voltage heavy-current air three-electrode switchboard with the graphite electrodes of KATG-50 on nominal voltage ±50 kV. This construction of switchboard KATG-50 has been passed experimental approbation in composition the heavy-current bit chain of powerful high-voltage generator of the аperiodic impulses of current of artificial linear lightning rationed on operating foreign standards with amplitude of Im=±(200±20 кА at their duration τP=(350±35 μs at level 0,5∙Im. Originality. First in domestic practice of development and creation of high-voltage heavy-current switchboards for the generators of large impulse currents of artificial lightning the ground of necessity of the use for their basic and managing electrodes of electrical engineering graphite is carried out. Practical value. The developed and made high-voltage heavy-current switchboard of cascade-tray KATG-50 from application in its composition of graphite electrodes possesses an enhanceable working resource and enhanceable stability of wearing-out at the use of similar switchboard in the bit chain of powerful pulsed current of the imitated linear lightning.

  1. Thermo-mechanical tests on W7-X current lead flanges

    Dhard, Chandra Prakash; Rummel, Thomas; Zacharias, Daniel; Bykov, Victor; Moennich, Thomas; Buscher, Klaus-Peter

    2013-01-01

    Highlights: • There are significant mechanical loads on the cryostat and radial flanges for W7-X current leads. • These are due to evacuation of W7-X cryostat, cool-down of cold mass, electro-magnetic forces and self weight of leads. • The actual mechanical loads were reduced to simplify the experimental set-up. • The tests were carried out on mock-up flanges test assembly at ambient temperature and at 77 K. • The thermo-mechanical tests on W7-X current lead flanges validate the design and joints of these flanges to the leads. -- Abstract: Fourteen pieces of high temperature superconducting current leads (CL) arranged in seven pairs, will be installed on the outer vessel of Wendelstein 7-X (W7-X) stellarator. In order to support the CL, it is provided with two glass fiber reinforce plastic (GFRP) flanges, namely, the lower cryostat flange (CF) remaining at room temperature and upper radial flange (RF) at about 5 K. Both the flanges i.e. CF and RF experience high mechanical loads with respect to the CL, due to the evacuation of W7-X cryostat, cool-down of cold mass including the CL, electro-magnetic forces due to current and plasma operations and self weight of CL. In order to check the integrity of these flanges for such mechanical loads, thermo-mechanical tests were carried out on these flanges at room temperatures and at liquid nitrogen (LN2) temperatures. The details of test set-up, results and modeling are described in the paper

  2. Development of modular thermostatic vapour-cooled current leads for cryogenic service

    Blessing, H.; Lebrun, P.

    1983-01-01

    Cryogenic current leads cooled by helium vapour have been developed, built and tested. Their construction, based on standard electrolytic copper braids crimped at the ends, is such as to provide flexible cold terminations and make possible a modular design. The warm terminations combine electrical insulation, leak-tightness and integrated thermostatic valves controlling lead temperature and avoiding thermal run-away or ice build-up. After giving a detailed description of their construction, this report presents results of performance and reliability tests made on prototype units. (orig.)

  3. Transient current in a quantum dot asymmetrically coupled to metallic leads

    Goker, A; Friedman, B A; Nordlander, P

    2007-01-01

    The time-dependent non-crossing approximation is used to study the transient current in a single-electron transistor attached asymmetrically to two leads following a sudden change in the energy of the dot level. We show that for asymmetric coupling, sharp features in the density of states of the leads can induce oscillations in the current through the dot. These oscillations persist to much longer timescales than the timescale for charge fluctuations. The amplitude of the oscillations increases as the temperature or source-drain bias across the dot is reduced and saturates for values below the Kondo temperature. We discuss the microscopic origin of these oscillations and comment on the possibility for their experimental detection

  4. Passivation of Flexible YBCO Superconducting Current Lead With Amorphous SiO2 Layer

    Johannes, Daniel; Webber, Robert

    2013-01-01

    Adiabatic demagnetization refrigerators (ADR) are operated in space to cool detectors of cosmic radiation to a few 10s of mK. A key element of the ADR is a superconducting magnet operating at about 0.3 K that is continually energized and de-energized in synchronism with a thermal switch, such that a piece of paramagnetic salt is alternately warm in a high magnetic field and cold in zero magnetic field. This causes the salt pill or refrigerant to cool, and it is able to suck heat from an object, e.g., the sensor, to be cooled. Current has to be fed into and out of the magnets from a dissipative power supply at the ambient temperature of the spacecraft. The current leads that link the magnets to the power supply inevitably conduct a significant amount of heat into the colder regions of the supporting cryostat, resulting in the need for larger, heavier, and more powerful supporting refrigerators. The aim of this project was to design and construct high-temperature superconductor (HTS) leads from YBCO (yttrium barium copper oxide) composite conductors to reduce the heat load significantly in the temperature regime below the critical temperature of YBCO. The magnet lead does not have to support current in the event that the YBCO ceases to be superconducting. Cus - tomarily, a normal metal conductor in parallel with the YBCO is a necessary part of the lead structure to allow for this upset condition; however, for this application, the normal metal can be dispensed with. Amorphous silicon dioxide is deposited directly onto the surface of YBCO, which resides on a flexible substrate. The silicon dioxide protects the YBCO from chemically reacting with atmospheric water and carbon dioxide, thus preserving the superconducting properties of the YBCO. The customary protective coating for flexible YBCO conductors is silver or a silver/gold alloy, which conducts heat many orders of magnitude better than SiO2 and so limits the use of such a composite conductor for passing current

  5. 600 A HTc current lead based on BSCCO 2212 rods for LHC magnets

    García-Tabarés, L; Abramian, P; Toral, F; Angurel, L A; Diez, J C; Burriel, R; Natividad, E; Iturbe, R; Etxeandia, J

    2000-01-01

    A 600 A current lead using 2212 BSCCO bulk material is now under construction and will be soon delivered to CERN. Present paper describes the main steps of its design and fabrication, including the two main parts in which it is divided, the superconducting module with the BSCCO rods and the conventional resistive part. An important role in this design was played by previous experimental measurements on subassemblies, which are also described along the paper. (5 refs).

  6. Low flow velocity, fine-screen heat exchangers and vapor-cooled cryogenic current leads

    Steyert, W.A.; Stone, N.J.

    1978-09-01

    The design, construction, and testing of three compact, low temperature heat exchangers are reported. A method is given for the construction of a small (approximately = 20-cm 3 volume) exchanger that can handle 6 g/s helium flow with low pressure drops (ΔP/P = 10 percent) and adequate heat transfer (N/sub tu/ = 3). The use of screen for simple, vapor-cooled current leads into cryogenic systems is also discussed

  7. Optimization of a Two Stage Pulse Tube Refrigerator for the Integrated Current Lead System

    Maekawa, R.; Matsubara, Y.; Okada, A.; Takami, S.; Konno, M.; Tomioka, A.; Imayoshi, T.; Hayashi, H.; Mito, T.

    2008-03-01

    Implementation of a conventional current lead with a pulse tube refrigerator has been validated to be working as an Integrated Current Lead (ICL) system for the Superconducting Magnetic Energy Storage (SMES). Realization of the system is primarily accounted for the flexibility of a pulse tube refrigerator, which does not posses any mechanical piston and/or displacer. As for an ultimate version of the ICL system, a High Temperature Superconducting (HTS) lead links a superconducting coil with a conventional copper lead. To ensure the minimization of heat loads to the superconducting coil, a pulse tube refrigerator has been upgraded to have a second cooling stage. This arrangement reduces not only the heat loads to the superconducting coil but also the operating cost for a SMES system. A prototype two-stage pulse tube refrigerator, series connected arrangement, was designed and fabricated to satisfy the requirements for the ICL system. Operation of the first stage refrigerator is a four-valve mode, while the second stage utilizes a double inlet configuration to ensure its confined geometry. The paper discusses the optimization of second stage cooling to validate the conceptual design

  8. Study of electromagnetic interference on quench detecting system of HTS current leads for EAST

    Hu, Yanlan; Li, Jiangang; Ji, Zhenshan; Zhu, C.M.; Zhen, L.G.; Xiao, Y.Z.

    2013-01-01

    Highlights: • EAST HTS superconducting magnet system shall be operating in a very noisy environment. • Voltage taps will have a lot of inductive voltage induced on them which makes quench detection very difficult. • The noise comes from the coupling between rapid pulsed poloidal coils, and radiation coupling interference associated with EAST heating systems;. • A series of related electromagnetic compatibility simulation tests have been carried out. • Electromagnetic noises are well restrained by choosing proper anti-interference means. -- Abstract: High temperature superconducting (HTS) material B-2223/Ag-Au has been used for EAST poloidal field (PF) coil current leads for reducing construction and operation cost of cryogenic system. The quench propagation velocity of HTS superconducting material is several orders of magnitude lower than that of normal low temperature current leads. It is difficult to detect weak signal of quench which is easily influenced by strong electromagnetic interference (EMI). In this paper, the sources of EMI from quench detecting system of high temperature current leads have been introduced. And we have chosen reasonable methods for good transformation and protection on the basis of electromagnetic compatibility simulation diagnosis experiments. Recent experimental results showed that the restraint of EMI has been achieved and has met the requirements of experiment

  9. submitter Manufacture and Test of ITER 10-kA HTSCL Prototypes

    Zhou, Tingzhi; Liu, Chenglian; Lu, Kun; Ran, Qingxiang; Song, Yuntao; Niu, Erwu; Bauer, Pierre; Devred, Arnaud; Lee, Seungje; Taylor, Thomas; Yang, Yifeng

    2016-01-01

    To carry current for the ITER correction coils, the 10-kA high-temperature superconducting current leads studied here are designed. Current leads provide the transition from 4.5-K low temperature to room temperature. This paper summarizes the major design features of the prototypes, which is followed by a discussion of the manufacturing and testing. The test results approved their excellent performance on low joint resistance and long loss-of-flow accident time. The overheating time, mass flow, and heat loads to 5-K ends also reached the expectation.

  10. Transient current in a quantum dot subject to a change in coupling to its leads

    Izmaylov, A F; Goker, A; Friedman, B A; Nordlander, P

    2006-01-01

    The time-dependent non-crossing approximation is used to calculate the transient currents through a quantum dot in the Kondo regime subject to a sudden change in its coupling to the leads. The currents are found to display transient non-universal behaviour immediately after the perturbation and then to follow a slow universal increase toward equilibrium. The timescales for the approach to equilibrium are shown to be the same as those recently identified in a study of transient currents in a quantum dot subject to a sudden change in the energy of the dot level (Plihal et al 2005 Phys. Rev. B 71 165321). We present improved numerical algorithms which enable relatively fast calculation of the transient response of quantum dots to sudden perturbations

  11. Could persistency of current of injury forecast successful active-fixation pacing lead implantation?

    Shali, Shalaimaiti; Su, Yangang; Qin, Shengmei; Ge, Junbo

    2018-05-01

    Presence of adequate current of injury (COI) was recognized as a sign of favorable pacemaker lead outcome. Little is known regarding the value of its dynamic behavior. We sought to test whether persistency of COI could predict active-fixation pacing lead performance. COI was monitored up to 10min after right ventricular (RV) pacing electrode fixation. COI persistency was defined as the percentage of COI magnitude relative to its initial measurement. An unacceptable pacing threshold (≥1.0V in acute evaluation or ≥2.0V over 2-year follow-up) with or without lead dislodgement was considered as lead failure. Lead implantation was attempted for 217 times in 174 patients (age 66.3±7.8years, 78 female). Acute lead failures occurred 43 times. Independent predictors of acute lead failure were RV enlargement (odds ratio [OR] 1.23, 95% confidential interval [CI] 1.11-2.04, P=0.033), absence of COI (OR 3.13, 95%CI 2.08-9.09, P=0.027), and COI persistency at 5min (OR 0.32, 95%CI 0.20-0.69, P=0.001) and 10min (OR 0.41, 95%CI 0.13-0.77, P=0.001). The optimal cutoffs were COI 5min persistency ≥50% (sensitivity 81.4%; specificity 81.9%) and COI 10min persistency ≥20% (sensitivity 86%; specificity 88.6%). There were 12 lead failures during 24.0±6.4months of follow-up. Patients with COI 5min persistency ≥50% had higher event-free survival compared to those with COI 5min persistency <50% (hazard ratio 3.54, 95% CI 1.04-12.06, P=0.043). COI persistency appears to be a valuable indicator for both acute and long-term outcome of active-fixation pacemaker leads. A precipitous decline in COI may require more attention to make sure of the lead performance. Copyright © 2018 Elsevier Ireland Ltd. All rights reserved.

  12. Electroplated reticulated vitreous carbon current collectors for lead-acid batteries: opportunities and challenges

    Gyenge, Elod; Jung, Joey; Mahato, Basanta

    Reticulated, open-cell structures based on vitreous carbon substrates electroplated with a Pb-Sn (1 wt.%) alloy were investigated as current collectors for lead-acid batteries. Scanning and backscattered electron microscopy, cyclic voltammetry, anodic polarization and flooded 2 V single-cell battery testing was employed to characterize the performance of the proposed collectors. A battery equipped with pasted electroplated reticulated vitreous carbon (RVC) electrodes of 137 cm 2 geometric area, at the time of manuscript submission, completed 500 cycles and over 1500 h of continuous operation. The cycling involved discharges at 63 A kg PAM-1 corresponding to a nominal 0.75 h rate and a positive active mass (PAM) utilization efficiency of 21%. The charging protocol was composed of two voltage limited (i.e. 2.6 V/cell), constant current steps of 35 and 9.5 A kg PAM-1, respectively, with a total duration of about 2 h. The charge factor was 1.05-1.15. The observed cycling behavior in conjunction with the versatility of electrodeposition to produce application-dependent optimized lead alloy coating thickness and composition shows promise for the development of lead-acid batteries using electroplated reticulated vitreous carbon collectors.

  13. Operational Experience and Consolidations for the Current Lead Control Valves of the Large Hadron Collider

    Perin, A; Pirotte, O; Krieger, B; Widmer, A

    2012-01-01

    The Large Hadron Collider superconducting magnets are powered by more than 1400 gas cooled current leads ranging from 120 A to 13000 A. The gas flow required by the leads is controlled by solenoid proportional valves with dimensions from DN 1.8 mm to DN 10 mm. During the first months of operation, signs of premature wear were found in the active parts of the valves. This created major problems for the functioning of the current leads threatening the availability of the LHC. Following the detection of the problems, a series of measures were implemented to keep the LHC running, to launch a development program to solve the premature wear problem and to prepare for a global consolidation of the gas flow control system. This article describes first the difficulties encountered and the measures taken to ensure a continuous operation of the LHC during the first year of operation. The development of new friction free valves is then presented along with the consolidation program and the test equipment developed to val...

  14. Effect of screening current induced pair breaking on magnetization of superconducting lead nanoparticles

    Yashwant, G.; Prajapat, C.L. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Jayakumar, O.D. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Singh, M.R.; Gupta, S.K. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Ravikumar, G. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India)], E-mail: gurazada@barc.gov.in

    2008-06-15

    Magnetization measurements on lead nanoparticles in the size range 35-45 nm are presented. It is shown that the critical fields in these nanoparticles are enhanced significantly above their bulk values with temperature dependence also distinct from that of bulk. The observed 'type II' like shape of the magnetization curves is explained on the basis of the Ginzburg-Landau phenomenology by invoking the pair breaking effect of the London screening currents, which makes the effective penetration depth an increasing function of the field. The temperature dependence of critical field is found to be consistent with our explanation.

  15. Lead-Lag relationships? Asynchrounous and Abrupt Shifts in Atmospheric Circulation, Temperature, and Vegetation during the 8.2 ka Event in the Eastern Mediterranean at Tenaghi Philippon, Greece

    Niedermeyer, E. M.; Mulch, A.; Pross, J.

    2017-12-01

    The "8.2 ka event" has been an abrupt and prominent climate perturbation during the Holocene, and is characterized by an episode of generally colder and dryer conditions in the Northern Hemisphere realm. However, evidence to what extent this event has had an impact on climate in the Mediterranean region is ambiguous, in particular with respect to rainfall, temperature and vegetation change on land. Here we present a new, high-resolution record (ø 15 years during the event) of paleotemperatures from the Tenaghi Philippon peat deposit, Eastern Macedonia, Greece, using the MBT'/CBT index based on brGDGTs (branched Glycerol-Dialkyl-Glycerol-Tetraethers). Our data show fairly stable temperatures before the event, which is initiated at 8.1 ka by an abrupt and continuous cooling during the first 35 years of the event. After a short, 10-year episode of minimum temperatures, the event is ended by a similarly abrupt and continuous warming within 38 years. Comparison of our record with a previous study of the stable hydrogen isotopic composition of higher-plant waxes (δDwax) on the same core1 shows that changes in temperature occurred simultaneously with shifts in atmospherics moisture sources (Mediterranean vs Atlantic). Interestingly, further comparison of our data with a previous palynological study of the same core2 reveals that changes in vegetation associated with the 8.2 ka event precede shifts in hydrology and temperature by 100 years. This suggests either pronounced changes in seasonality of temperature and rainfall after the onset of the 8.2 ka event, i.e. at the peak of the event, or that changes in local atmospheric circulation (moisture sources) and temperature where not the initial trigger of changes in vegetation. References: Pross, J., Kotthoff, U., Müller, U.C., Peyron, O., Dormoy, I., Schmiedl, G., Kalaitzidis, S. and Smith, A.M. (2009): Massive perturbation in terrestrial ecosystems of the Eastern Mediterranean region associated with the 8.2 kyr B

  16. Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

    Fang, J.; Yu, T.; Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J.

    2013-01-01

    Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current

  17. Comparison and analysis of the efficiency of heat exchange of copper rod and copper wires current lead

    Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Yu, T. [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Li, Z.M.; Wei, B.; Qiu, M.; Zhang, H.J. [China Electric Power Research Institute, Haidian District, Beijing (China)

    2013-11-15

    Highlights: •An optimized design of HTS binary current leads is proposed. •Temperature distributions of two different current leads are calculated. •Experiments are done to certify the calculated temperature distributions. •The experiments proved that the copper wires increase security margins. -- Abstract: Current leads are the key components that connect the low-temperature and high temperature parts of the cryogenic system. Owing to the wide range of temperatures, current leads are the main sources of heat leakage. Since the HTS tapes have no resistance and the generated Joule heat is almost zero, HTS binary current leads can reduce heat leakage compared to the conventional leads. However, heat will still be generated and conducted to the cryogenic system through the copper parts of the HTS current leads. In order to reduce heat leakage by the copper parts of the HTS current leads, this paper presents an optimized design of the copper parts of HTS binary current leads. Inside the leads, the copper wires were applied as an alternative to the copper rod without changing the overall dimensions. Firstly, the differential function of heat transfer was derived. By solving the function, the optimum number of the copper wires and the temperature distribution of two different current leads were gotten. Then the experiment of the temperature distribution was done, and the experimental results were basically the same with the calculative results. The simulation and related experiments proved that the copper wire can increase security margins and reduce maximum temperatures under the same shunt current.

  18. The 12-lead electrocardiogram and risk of sudden death: current utility and future prospects.

    Narayanan, Kumar; Chugh, Sumeet S

    2015-10-01

    More than 100 years after it was first invented, the 12-lead electrocardiogram (ECG) continues to occupy an important place in the diagnostic armamentarium of the practicing clinician. With the recognition of relatively rare but important clinical entities such as Wolff-Parkinson-White and the long QT syndrome, this clinical tool was firmly established as a test for assessing risk of sudden cardiac death (SCD). However, over the past two decades the role of the ECG in risk prediction for common forms of SCD, for example in patients with coronary artery disease, has been the focus of considerable investigation. Especially in light of the limitations of current risk stratification approaches, there is a renewed focus on this broadly available and relatively inexpensive test. Various abnormalities of depolarization and repolarization on the ECG have been linked to SCD risk; however, more focused work is needed before they can be deployed in the clinical arena. The present review summarizes the current knowledge on various ECG risk markers for prediction of SCD and discusses some future directions in this field. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  19. Ka-Band MMIC Subarray Technology Program (Ka-Mist)

    Pottinger, W.

    1995-01-01

    Ka-band monolithic microwave integrated circuit (MMIC) arrays have been considered as having high potential for increasing the capability of space, aircraft, and land mobile communication systems in terms of scan performance, data rate, link margin, and flexibility while offering a significant reduction in size, weight, and power consumption. Insertion of MMIC technology into antenna systems, particularly at millimeter wave frequencies using low power and low noise amplifiers in closed proximity to the radiating elements, offers a significant improvement in the array transmit efficiency, receive system noise figure, and overall array reliability. Application of active array technology also leads to the use of advanced beamforming techniques that can improve beam agility, diversity, and adaptivity to complex signal environments. The objective of this program was to demonstrate the technical feasibility of the 'tile' array packaging architecture at EHF via the insertion of 1990 MMIC technology into a functional tile array or subarray module. The means test of this objective was to demonstrate and deliver to NASA a minimum of two 4 x 4 (16 radiating element) subarray modules operating in a transmit mode at 29.6 GHz. Available (1990) MMIC technology was chosen to focus the program effort on the novel interconnect schemes and packaging requirements rather than focusing on MMIC development. Major technical achievements of this program include the successful integration of two 4 x 4 subarray modules into a single antenna array. This 32 element array demonstrates a transmit EIRP of over 300 watts yielding an effective directive power gain in excess of 55 dB at 29.63 GHz. The array has been actively used as the transmit link in airborne/terrestrial mobile communication experiments accomplished via the ACTS satellite launched in August 1993.

  20. Deep-Space Ka-Band Flight Experience

    Morabito, D. D.

    2017-11-01

    Lower frequency bands have become more congested in allocated bandwidth as there is increased competition between flight projects and other entities. Going to higher frequency bands offers significantly more bandwidth, allowing for the use of much higher data rates. However, Ka-band is more susceptible to weather effects than lower frequency bands currently used for most standard downlink telemetry operations. Future or prospective flight projects considering deep-space Ka-band (32-GHz) telemetry data links have expressed an interest in understanding past flight experience with received Ka-band downlink performance. Especially important to these flight projects is gaining a better understanding of weather effects from the experience of current or past missions that operated Ka-band radio systems. We will discuss the historical flight experience of several Ka-band missions starting from Mars Observer in 1993 up to present-day deep-space missions such as Kepler. The study of historical Ka-band flight experience allows one to recommend margin policy for future missions. Of particular interest, we will review previously reported-on flight experience with the Cassini spacecraft Ka-band radio system that has been used for radio science investigations as well as engineering studies from 2004 to 2015, when Cassini was in orbit around the planet Saturn. In this article, we will focus primarily on the Kepler spacecraft Ka-band link, which has been used for operational telemetry downlink from an Earth trailing orbit where the spacecraft resides. We analyzed the received Ka-band signal level data in order to characterize link performance over a wide range of weather conditions and as a function of elevation angle. Based on this analysis of Kepler and Cassini flight data, we found that a 4-dB margin with respect to adverse conditions ensures that we achieve at least a 95 percent data return.

  1. Lead emissions from road transport in Europe. A revision of current estimates using various estimation methodologies

    Denier van der Gon, H.A.C.; Appelman, W.

    2009-01-01

    Large-scale use of leaded gasoline was an important source of the neurotoxin lead in the European environment. After a sequence of regulations on the allowed gasoline lead content and, eventually, a ban on the use of lead additives in gasoline, road transport was no longer considered a source of

  2. High Tc superconducting current leads laser fabrication

    Díez, J. C.

    1998-04-01

    Full Text Available In this work is described a laser float zone melting method designed in our laboratory to the development of superconductor Bi2Sr2CaCu2O8 current leads. The most relevant results obtained with different grown conditions and the influence of the process parameters in the properties of superconductor leads are presented.

    Las barras de alimentación basadas en el superconductor Bi2Sr2CaCu2O8 son de gran interés práctico para la fabricación de criogeneradores capaces de refrigerar bobinas superconductoras a temperaturas inferiores a 77 K e incluso cercanas a 5 K. Las propiedades mecánicas y eléctricas de dichas barras son fundamentales para determinar su grado de fiabilidad, que en última instancia determinar su aplicabilidad a escala comercial. Los parámetros de fabricación utilizando la fusión zonal inducida por láser permiten obtener fibras gruesas de este superconductor capaces de transportar elevadas corrientes a 77 K y a temperaturas inferiores, y con un comportamiento aceptable frente al ciclado térmico y al paso de elevadas intensidades de corriente eléctrica. En este trabajo se describe un sistema de fusión zonal láser diseñado en nuestro laboratorio para el desarrollo de superconductores y se resumen los resultados más significativos obtenidos según las diversas condiciones de crecimiento estudiadas, la influencia de los diversos parámetros de procesado utilizados sobre las propiedades de las fibras superconductoras obtenidas, así como su potencial uso en dispositivos prácticos.

  3. Analysis of induced electrical currents from magnetic field coupling inside implantable neurostimulator leads

    Seidman Seth J

    2011-10-01

    Full Text Available Abstract Background Over the last decade, the number of neurostimulator systems implanted in patients has been rapidly growing. Nearly 50, 000 neurostimulators are implanted worldwide annually. The most common type of implantable neurostimulators is indicated for pain relief. At the same time, commercial use of other electromagnetic technologies is expanding, making electromagnetic interference (EMI of neurostimulator function an issue of concern. Typically reported sources of neurostimulator EMI include security systems, metal detectors and wireless equipment. When near such sources, patients with implanted neurostimulators have reported adverse events such as shock, pain, and increased stimulation. In recent in vitro studies, radio frequency identification (RFID technology has been shown to inhibit the stimulation pulse of an implantable neurostimulator system during low frequency exposure at close distances. This could potentially be due to induced electrical currents inside the implantable neurostimulator leads that are caused by magnetic field coupling from the low frequency identification system. Methods To systematically address the concerns posed by EMI, we developed a test platform to assess the interference from coupled magnetic fields on implantable neurostimulator systems. To measure interference, we recorded the output of one implantable neurostimulator, programmed for best therapy threshold settings, when in close proximity to an operating low frequency RFID emitter. The output contained electrical potentials from the neurostimulator system and those induced by EMI from the RFID emitter. We also recorded the output of the same neurostimulator system programmed for best therapy threshold settings without RFID interference. Using the Spatially Extended Nonlinear Node (SENN model, we compared threshold factors of spinal cord fiber excitation for both recorded outputs. Results The electric current induced by low frequency RFID emitter

  4. Deep space propagation experiments at Ka-band

    Butman, Stanley A.

    1990-01-01

    Propagation experiments as essential components of the general plan to develop an operational deep space telecommunications and navigation capability at Ka-band (32 to 35 GHz) by the end of the 20th century are discussed. Significant benefits of Ka-band over the current deep space standard X-band (8.4 GHz) are an improvement of 4 to 10 dB in telemetry capacity and a similar increase in radio navigation accuracy. Propagation experiments are planned on the Mars Observer Mission in 1992 in preparation for the Cassini Mission to Saturn in 1996, which will use Ka-band in the search for gravity waves as well as to enhance telemetry and navigation at Saturn in 2002. Subsequent uses of Ka-band are planned for the Solar Probe Mission and the Mars Program.

  5. Current Problems and Possible Solutions in High-Temperature Lead-Free Soldering

    Kroupa, Aleš; Andersson, D.; Hoo, N.; Pearce, J.; Watson, A.; Dinsdale, A.; Mucklejohn, S.

    2012-01-01

    Roč. 21, č. 5 (2012), s. 629-637 ISSN 1059-9495 Institutional support: RVO:68081723 Keywords : lead-free soldering, * materials for high-temperature LF * new technologies for HT lead-free soldering Subject RIV: BJ - Thermodynamics Impact factor: 0.915, year: 2012

  6. Glazed clay pottery and lead exposure in Mexico: Current experimental evidence.

    Diaz-Ruiz, Araceli; Tristán-López, Luis Antonio; Medrano-Gómez, Karen Itzel; Torres-Domínguez, Juan Alejandro; Ríos, Camilo; Montes, Sergio

    2017-11-01

    Lead exposure remains a significant environmental problem; lead is neurotoxic, especially in developing humans. In Mexico, lead in human blood is still a concern. Historically, much of the lead exposure is attributed to the use of handcrafted clay pottery for cooking, storing and serving food. However, experimental cause-and-effect demonstration is lacking. The present study explores this issue with a prospective experimental approach. We used handcrafted clay containers to prepare and store lemonade, which was supplied as drinking water to pregnant rats throughout the gestational period. We found that clay pots, jars, and mugs leached on average 200 µg/l lead, and exposure to the lemonade resulted in 2.5 µg/dl of lead in the pregnant rats' blood. Neonates also showed increased lead content in the hippocampus and cerebellum. Caspase-3 activity was found to be statistically increased in the hippocampus in prenatally exposed neonates, suggesting increased apoptosis in that brain region. Glazed ceramics are still an important source of lead exposure in Mexico, and our results confirm that pregnancy is a vulnerable period for brain development.

  7. Web-service for integration of current information from the leading MOOCs

    Sergey P. Timoshin

    2017-01-01

    Full Text Available Purpose. A phenomenon called MOOC (Massive Open Online Course plays a special, “revolutionary” role, introducing of online learning for all stages of the educational process. Today there are a lot of MOOCs, the largest of them: Coursera, edX, Udacity. In connection with the large amount of resources for additional education, a number of questions arise: “How to choose the suitable course as an additional education, how to use the capabilities of MOOCs to improve the quality of the educational process at the university, how to minimize the time for finding the desired course on different platforms?”The purpose of the work is to create a unified information resource that allows you to integrate relevant information from various MOOCs, to reduce the time for finding an appropriate online course for the user, and to raise awareness about new courses and popular specializations, related to information technology.Materials and methods. Web-service is designed as one of the components of the information-educational environment of the Institute of System Analysis and Management. It is aimed at different groups of users: “motivated” students, “unmotivated” students, and lecturers.The initial data for the service is open information about the current online courses on the MOOCs Coursera, edX and Udacity.Each project has its own API, which allows you to get information about online courses. Since MOOCs do not have a common vocabulary in order to use it for searching, there is the problem of creating such a dictionary. To do this we use the Stack Exchange resource (stackexchange.com. The list of keywords is formed through the Stack Exchange API – we select the most popular tags on sites softwareengineering.stackexchange.com and cs.stackexchange.com.Results. As the first stage of implementation, a web application was developed that allows you to view and filter the lists of courses and to see detailed information about the courses

  8. Estimation of the exchange current density and comparative analysis of morphology of electrochemically produced lead and zinc deposits

    Nikolić Nebojša D.

    2017-01-01

    Full Text Available The processes of lead and zinc electrodeposition from the very dilute electrolytes were compared by the analysis of polarization characteristics and by the scanning electron microscopic (SEM analysis of the morphology of the deposits obtained in the galvanostatic regime of electrolysis. The exchange current densities for lead and zinc were estimated by comparison of experimentally obtained polarization curves with the simulated ones obtained for the different the exchange current density to the limiting diffusion current density ratios. Using this way for the estimation of the exchange current density, it is shown that the exchange current density for Pb was more than 1300 times higher than the one for Zn. In this way, it is confirmed that the Pb electrodeposition processes are considerably faster than the Zn electrodeposition processes. The difference in the rate of electrochemical processes was confirmed by a comparison of morphologies of lead and zinc deposits obtained at current densities which corresponded to 0.25 and 0.50 values of the limiting diffusion current densities. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172046

  9. On the development of protein pKa calculation algorithms

    Carstensen, Tommy; Farrell, Damien; Huang, Yong; Baker, Nathan A.; Nielsen, Jens Erik

    2011-01-01

    Protein pKa calculation methods are developed partly to provide fast non-experimental estimates of the ionization constants of protein side chains. However, the most significant reason for developing such methods is that a good pKa calculation method is presumed to provide an accurate physical model of protein electrostatics, which can be applied in methods for drug design, protein design and other structure-based energy calculation methods. We explore the validity of this presumption by simulating the development of a pKa calculation method using artificial experimental data derived from a human-defined physical reality. We examine the ability of an RMSD-guided development protocol to retrieve the correct (artificial) physical reality and find that a rugged optimization landscape and a huge parameter space prevent the identification of the correct physical reality. We examine the importance of the training set in developing pKa calculation methods and investigate the effect of experimental noise on our ability to identify the correct physical reality, and find that both effects have a significant and detrimental impact on the physical reality of the optimal model identified. Our findings are of relevance to all structure-based methods for protein energy calculations and simulation, and have large implications for all types of current pKa calculation methods. Our analysis furthermore suggests that careful and extensive validation on many types of experimental data can go some way in making current models more realistic. PMID:21744393

  10. Design of electronic measurement and quench detection equipment for the Current Lead Test facility Karlsruhe (CuLTKa)

    Hollik, Markus; Fietz, Walter H.; Fink, Stefan; Gehrlein, Mirko; Heller, Reinhard; Lange, Christian; Möhring, Tobias

    2013-01-01

    The Current Lead Test facility Karlsruhe (CuLTKa) is under construction at the Karlsruhe Institute of Technology (KIT) to perform acceptance tests of high temperature superconductor (HTS) current leads (CL). CuLTKa is in progress and present planning expects the completion in 2013. The data acquisition system is based on a modular design with electronic measurement and monitoring equipment covering a test voltage of 50 kV DC against ground. It provides plug-in units which enable temperature and voltage measurement at high voltage potential and in addition quench detection units which detect a loss of superconductivity reliably and quickly to avoid damage of the superconducting device under test. Prototype units for quench detection, temperature and voltage measurement have been successfully tested. Six temperature measurement units are already in use in the KIT test facility TOSKA and operated reliably during the acceptance tests of the HTS current leads for Wendelstein 7-X (W7-X) in 2011/2012. CuLTKa will be used first for 26 current leads which will be built in KIT for the fusion experiment JT-60SA. The present paper gives an overview of the design of the electronic measurement and quench detection equipment

  11. Alternating current loss characteristics in (bismuth,lead)SCCO and yttrium barium copper oxide superconducting tapes

    Nguyen, Doan Ngoc

    Alternating current (AC) loss and current carrying capacity are two of the most crucial considerations in large-scale power applications of high temperature superconducting (HTS) conductors. AC losses result in an increased thermal load for cooling machines, and thus increased operating costs. Furthermore, AC losses can stimulate quenching phenomena or at least decrease the stability margin for superconducting devices. Thus, understanding AC losses is essential for the development of HTS AC applications. The main focus of this dissertation is to make reliable total AC loss measurements and interpret the experimental results in a theoretical framework. With a specially designed magnet, advanced total AC loss measurement system in liquid nitrogen (77 K) has been successfully built. Both calorimetric and electromagnetic methods were employed to confirm the validity of the measured results and to have a more thorough understanding of AC loss in HTS conductors. The measurement is capable of measuring total AC loss in HTS tapes over a wide range of frequency and amplitude of transport current and magnetic field. An accurate phase control technique allows measurement of total AC loss with any phase difference between the transport current and magnetic field by calorimetric method. In addition, a novel total AC loss measurement system with variable temperatures from 30 K to 100 K was successfully built and tested. Understanding the dependence of AC losses on temperature will enable optimization of the operating temperature and design of HTS devices. As a part of the dissertation, numerical calculations using Brandt's model were developed to study electrodynamics and total AC loss in HTS conductors. In the calculations, the superconducting electrical behavior is assumed to follow a power-law model. In general, the practical properties of conductors, including field-dependence of critical current density Jc, n-value and non-uniform distribution of Jc, can be accounted for in

  12. Light-current-induced acceleration of degradation of methylammonium lead iodide perovskite solar cells

    Xiang, Yuren; Zhang, Fan; He, Junjie; Lian, Jiarong; Zeng, Pengju; Song, Jun; Qu, Junle

    2018-04-01

    The photo-conversion efficiency of perovskite solar cells (PSCs) has been improved considerably in recent years, but the poor stability of PSCs still prevents their commercialization. In this report, we use the rate of the integrated short-circuit current change (Drate) to investigate the performance degradation kinetics and identify the degradation of PSCs that is accelerated by the light current. The value of Drate increases by an order of magnitude from about 0.02 to 0.35 mA cm-2·min-1 after light-IV testing. The accelerated degradation progress is proven to be dominated by the hydration process and the migration of the iodine ions of the light current. The migration of the iodine ions enhances the hydration process through a chain reaction, enabling the formation of fast diffusion channels for both H2O and O2, which induce the rapid decomposition of the perovskite film and increase the density of the trap state. The X-ray photoelectron spectroscopy measurement data also indicate that the super oxygen may be formed due to the PCBM damage caused by the migration iodine ions. An understanding of the degradation acceleration mechanism would provide an insight into the effect of ion migration on the stability of PSCs.

  13. Early response to sibutramine in patients not meeting current label criteria: preliminary analysis of SCOUT lead-in period

    Caterson, Ian; Coutinho, Walmir; Finer, Nick

    2010-01-01

    The Sibutramine Cardiovascular Outcomes (SCOUT) trial protocol defines a patient population predominantly outside current European Union label criteria. This article explores responses to sibutramine during the 6-week, single-blind, lead-in period between patients who conformed to the label...... requirements ("conformers") and those who did not ("nonconformers"). SCOUT is an ongoing, randomized, double-blind, placebo-controlled outcome trial in overweight/obese patients at high risk of a cardiovascular event. In total, 10,742 patients received sibutramine and weight management during the lead...... with sibutramine confirms its good tolerability and efficacy in patients who meet current label criteria. Preliminary data from high-risk patients for whom sibutramine is currently contraindicated suggest a low discontinuation rate and few serious adverse events but confirmation from the SCOUT outcome data...

  14. Leading article: Use of smartphones to pass on information about patients - what are the current issues?

    Rokadiya, S; McCaul, J A; Mitchell, D A; Brennan, P A

    2016-07-01

    Many doctors now use mobile devices such as smartphones to communicate with one another about their patients, and sometimes this is without the knowledge and approval of their employer. We know of little information about the use of texting and other web-based messaging services by doctors in hospitals, so we reviewed relevant published studies to assess the safety and usefulness of current methods of digital communication. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  15. Current Hypotheses on How Microsatellite Instability Leads to Enhanced Survival of Lynch Syndrome Patients

    Kristen M. Drescher

    2010-01-01

    Full Text Available High levels of microsatellite instability (MSI-high are a cardinal feature of colorectal tumors from patients with Lynch Syndrome. Other key characteristics of Lynch Syndrome are that these patients experience fewer metastases and have enhanced survival when compared to patients diagnosed with microsatellite stable (MSS colorectal cancer. Many of the characteristics associated with Lynch Syndrome including enhanced survival are also observed in patients with sporadic MSI-high colorectal cancer. In this review we will present the current state of knowledge regarding the mechanisms that are utilized by the host to control colorectal cancer in Lynch Syndrome and why these same mechanisms fail in MSS colorectal cancers.

  16. Current hypotheses on how microsatellite instability leads to enhanced survival of Lynch Syndrome patients.

    Drescher, Kristen M; Sharma, Poonam; Lynch, Henry T

    2010-01-01

    High levels of microsatellite instability (MSI-high) are a cardinal feature of colorectal tumors from patients with Lynch Syndrome. Other key characteristics of Lynch Syndrome are that these patients experience fewer metastases and have enhanced survival when compared to patients diagnosed with microsatellite stable (MSS) colorectal cancer. Many of the characteristics associated with Lynch Syndrome including enhanced survival are also observed in patients with sporadic MSI-high colorectal cancer. In this review we will present the current state of knowledge regarding the mechanisms that are utilized by the host to control colorectal cancer in Lynch Syndrome and why these same mechanisms fail in MSS colorectal cancers.

  17. A thermally switched 9 kA superconducting rectifier fluxpump

    ten Kate, Herman H.J.; Bunk, Paul B.; Steffens, Harry A.; van de Klundert, Louis J.M.

    1981-01-01

    The feasibility of superconducting rectifier-fluxpumps has to be demonstrated at current levels of 10 - 100 kA, where is asked for in the superconducting devices now being planned. An intensive program has been started at the low temperature division of the University of Twente to construct such

  18. Study of charged hadron multiplicities in charged-current neutrino-lead interactions in the OPERA detector

    Agafonova, N.; Malgin, A.; Matveev, V.; Ryazhskaya, O.; Shakirianova, I. [INR - Institute for Nuclear Research, Russian Academy of Sciences, Moscow (Russian Federation); Aleksandrov, A.; Buontempo, S.; Consiglio, L.; Tioukov, V.; Voevodina, E. [INFN Sezione di Napoli, Naples (Italy); Anokhina, A.; Dzhatdoev, T.; Podgrudkov, D.; Roganova, T. [Lomonosov Moscow State University, SINP MSU - Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Aoki, S.; Hara, T.; Mizutani, F.; Ozaki, K.; Shibayama, E.; Takahashi, S. [Kobe University, Kobe (Japan); Ariga, A.; Ereditato, A.; Kreslo, I.; Vuilleumier, J.L. [University of Bern, Laboratory for High Energy Physics (LHEP), Albert Einstein Center for Fundamental Physics, Bern (Switzerland); Ariga, T. [University of Bern, Laboratory for High Energy Physics (LHEP), Albert Einstein Center for Fundamental Physics, Bern (Switzerland); Kyushu University, Faculty of Arts and Science, Fukuoka (Japan); Bertolin, A.; Dusini, S.; Kose, U.; Longhin, A.; Pupilli, F.; Stanco, L. [INFN Sezione di Padova, Padua (Italy); Bodnarchuk, I.; Chukanov, A.; Dmitrievski, S.; Gornushkin, Y.; Sotnikov, A.; Vasina, S. [JINR - Joint Institute for Nuclear Research, Dubna (Russian Federation); Bozza, C.; Grella, G.; Stellacci, S.M. [Dipartimento di Fisica, Universita di Salerno (Italy); ' ' Gruppo Collegato' ' INFN, Fisciano, Salerno (Italy); Brugnera, R.; Garfagnini, A.; Laudisio, F.; Medinaceli, E.; Roda, M.; Sirignano, C. [INFN Sezione di Padova, Padua (Italy); Dipartimento di Fisica e Astronomia, Universita di Padova, Padua (Italy); Buonaura, A.; De Lellis, G.; Di Crescenzo, A.; Galati, G.; Hosseini, B.; Lauria, A.; Montesi, M.C.; Strolin, P. [INFN Sezione di Napoli, Naples (Italy); Dipartimento di Fisica, Universita Federico II di Napoli, Naples (Italy); Chernyavskiy, M.; Gorbunov, S.; Okateva, N.; Shchedrina, T.; Starkov, N. [LPI - Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation); D' Ambrosio, N.; Di Marco, N.; Schembri, A. [INFN-Laboratori Nazionali del Gran Sasso, Assergi, L' Aquila (Italy); De Serio, M.; Muciaccia, M.T.; Paparella, L.; Pastore, A.; Simone, S. [Dipartimento di Fisica, Universita di Bari, Bari (Italy); INFN Sezione di Bari, Bari (Italy); Amo Sanchez, P. del; Duchesneau, D.; Pessard, H. [LAPP, Universite Savoie Mont Blanc, CNRS/IN2P3, Annecy-le-Vieux (France); Di Ferdinando, D.; Mandrioli, G.; Patrizii, L.; Sirri, G.; Tenti, M. [INFN Sezione di Bologna, Bologna (Italy); Dracos, M.; Jollet, C.; Meregaglia, A. [IPHC, Universite de Strasbourg, CNRS/IN2P3, Strasbourg (France); Ebert, J.; Hagner, C.; Hollnagel, A.; Wonsak, B. [Hamburg University, Hamburg (Germany); Fini, R.A. [INFN Sezione di Bari, Bari (Italy); Fornari, F.; Mauri, N.; Pasqualini, L.; Pozzato, M. [INFN Sezione di Bologna, Bologna (Italy); Dipartimento di Fisica e Astronomia, Universita di Bologna, Bologna (Italy); Fukuda, T.; Hayakawa, T.; Ishiguro, K.; Kitagawa, N.; Komatsu, M.; Miyanishi, M.; Morishima, K.; Naganawa, N.; Naka, T.; Nakamura, M.; Nakano, T.; Niwa, K.; Rokujo, H.; Sato, O.; Shiraishi, T. [Nagoya University, Nagoya (Japan); Gentile, V. [Gran Sasso Science Institute, L' Aquila (Italy); Goldberg, J. [Technion, Department of Physics, Haifa (Israel); Guler, A.M.; Kamiscioglu, M. [METU - Middle East Technical University, Ankara (Turkey); Gustavino, C.; Loverre, P.; Monacelli, P.; Rosa, G. [INFN Sezione di Roma, Rome (Italy); Jakovcic, K.; Ljubicic, A.; Malenica, M. [Rudjer Boskovic Institute, Zagreb (Croatia); Kamiscioglu, C. [METU - Middle East Technical University, Ankara (Turkey); Ankara University, Ankara (Turkey); Kim, S.H.; Park, B.D.; Yoon, C.S. [Gyeongsang National University, Jinju (Korea, Republic of); Klicek, B.; Stipcevic, M. [Center of Excellence for Advanced Materials and Sensing Devices, Ruder Boskovic Institute, Zagreb (Croatia); Kodama, K. [Aichi University of Education, Kariya, Aichi (Japan); Matsuo, T.; Ogawa, S.; Shibuya, H. [Toho University, Funabashi (Japan); Mikado, S. [Nihon University, Narashino, Chiba (Japan); Paoloni, A.; Spinetti, M.; Votano, L. [INFN - Laboratori Nazionali di Frascati, Rome (Italy); Polukhina, N. [LPI - Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation); Moscow Engineering Physical Institute Moscow, Moscow (Russian Federation); Terranova, F. [Dipartimento di Fisica, Universita di Milano-Bicocca, Milan (Italy); Vilain, P.; Wilquet, G. [IIHE, Universite Libre de Bruxelles, Brussels (Belgium)

    2018-01-15

    The OPERA experiment was designed to search for ν{sub μ} → ν{sub τ} oscillations in appearance mode through the direct observation of tau neutrinos in the CNGS neutrino beam. In this paper, we report a study of the multiplicity of charged particles produced in charged-current neutrino interactions in lead. We present charged hadron average multiplicities, their dispersion and investigate the KNO scaling in different kinematical regions. The results are presented in detail in the form of tables that can be used in the validation of Monte Carlo generators of neutrino-lead interactions. (orig.)

  19. Current modeling practice may lead to falsely high benchmark dose estimates.

    Ringblom, Joakim; Johanson, Gunnar; Öberg, Mattias

    2014-07-01

    Benchmark dose (BMD) modeling is increasingly used as the preferred approach to define the point-of-departure for health risk assessment of chemicals. As data are inherently variable, there is always a risk to select a model that defines a lower confidence bound of the BMD (BMDL) that, contrary to expected, exceeds the true BMD. The aim of this study was to investigate how often and under what circumstances such anomalies occur under current modeling practice. Continuous data were generated from a realistic dose-effect curve by Monte Carlo simulations using four dose groups and a set of five different dose placement scenarios, group sizes between 5 and 50 animals and coefficients of variations of 5-15%. The BMD calculations were conducted using nested exponential models, as most BMD software use nested approaches. "Non-protective" BMDLs (higher than true BMD) were frequently observed, in some scenarios reaching 80%. The phenomenon was mainly related to the selection of the non-sigmoidal exponential model (Effect=a·e(b)(·dose)). In conclusion, non-sigmoid models should be used with caution as it may underestimate the risk, illustrating that awareness of the model selection process and sound identification of the point-of-departure is vital for health risk assessment. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Development of a thermally switched superconducting rectifier for 100 kA

    Mulder, G.B.J.; Mulder, G.B.J.; ten Kate, Herman H.J.; Krooshoop, Hendrikus J.G.; van de Klundert, L.J.M.; van de Klundert, L.J.M.

    1991-01-01

    A full-wave superconducting rectifier for 100 kA has been developed. Typical design values of this device are: a secondary current of 100 kA, a primary amplitude of 20 A, an operating frequency of 0.5 Hz, and an average power on the order of 100 W. The rectification is achieved by means of thermally

  1. Domestic UK retrofit challenge: Barriers, incentives and current performance leading into the Green Deal

    Dowson, Mark; Poole, Adam; Harrison, David; Susman, Gideon

    2012-01-01

    This paper reviews the thermal performance of the existing UK housing stock, the main fabric efficiency incentive schemes and the barriers to obtaining deep energy and CO 2 savings throughout the stock. The UK faces a major challenge to improve the thermal performance of its existing housing stock. Millions of dwellings possess ‘hard-to-treat’ solid walls and have glazing which is not cost effective to improve. A range of fabric efficiency incentive schemes exist, but many do not target the full range of private and social housing. From now on, the Green Deal will be the UK's key energy efficiency policy. However, the scheme is forecasted to have low consumer appeal and low incentives for investors. Moreover, calculated Green Deal loan repayments will be reliant upon estimated energy savings, yet it is claimed that retrofit measures may only be half as effective as anticipated due to a lack of monitoring, poor quality installation and the increased use of heating following refurbishment. Looking to Germany, there has been success through the Passivhaus standard, but the UK currently lacks appropriate skills and cost effective components to replicate this approach. In addition, the embodied energy in retrofit products and materials threatens to counter operational savings. - Highlights: ► CERT, CESP, Decent homes and Warm Front have not targeted the full extent of private and social homes. ► There is a risk that Green Deal will fail due to low consumer appeal and low incentives for investors. ► Up to half of the predicted energy savings from whole house retrofits may not be achieved in practice. ► Passivhaus is identified as best practice for retrofit, yet there is a lack of skills and components. ► Embodied energy in materials and components must be better understood to achieve life cycle savings.

  2. Fade Mitigation Techniques at Ka-Band

    Dissanayake, Asoka (Editor)

    1996-01-01

    Rain fading is the dominant propagation impairment affecting Ka-band satellite links and rain fade mitigation is a key element in the design of Ka-band satellite networks. Some of the common fade mitigation techniques include: power control, diversity, adaptive coding, and resource sharing. The Advanced Communications Technology Satellite (ACTS) provides an excellent opportunity to develop and test Ka-band rain impairment amelioration techniques. Up-link power control and diversity are discussed in this paper.

  3. DARHT 2 kA Cathode Development

    Henestroza, E.; Houck, T.; Kwan, J.W.; Leitner, M.; Miram, G.; Prichard, B.; Roy, P.K.; Waldron, W.; Westenskow, G.; Yu, S.; Bieniosek, F.M.

    2009-03-09

    In the campaign to achieve 2 kA of electron beam current, we have made several changes to the DARHT-II injector during 2006-2007. These changes resulted in a significant increase in the beam current, achieving the 2 kA milestone. Until recently (before 2007), the maximum beam current that was produced from the 6.5-inch diameter (612M) cathode was about 1300 A when the cathode was operating at a maximum temperature of 1140 C. At this temperature level, the heat loss was dominated by radiation which is proportional to temperature to the fourth power. The maximum operating temperature was limited by the damage threshold of the potted filament and the capacity of the filament heater power supply, as well as the shortening of the cathode life time. There were also signs of overheating at other components in the cathode assembly. Thus it was clear that our approach to increase beam current could not be simply trying to run at a higher temperature and the preferred way was to operate with a cathode that has a lower work function. The dispenser cathode initially used was the type 612M made by SpectraMat. According to the manufacturer's bulletin, this cathode should be able to produce more than 10 A/cm{sup 2} of current density (corresponding to 2 kA of total beam current) at our operating conditions. Instead the measured emission (space charge limited) was 6 A/cm{sup 2}. The result was similar even after we had revised the activation and handling procedures to adhere more closely to the recommend steps (taking longer time and nonstop to do the out-gassing). Vacuum was a major concern in considering the cathode's performance. Although the vacuum gauges at the injector vessel indicated 10{sup -8} Torr, the actual vacuum condition near the cathode in the central region of the vessel, where there might be significant out-gassing from the heater region, was never determined. Poor vacuum at the surface of the cathode degraded the emission (by raising the work function

  4. DARHT 2 kA Cathode Development

    Henestroza, E.; Houck, T.; Kwan, J.W.; Leitner, M.; Miram, G.; Prichard, B.; Roy, P.K.; Waldron, W.; Westenskow, G.; Yu, S.; Bieniosek, F.M.

    2009-01-01

    In the campaign to achieve 2 kA of electron beam current, we have made several changes to the DARHT-II injector during 2006-2007. These changes resulted in a significant increase in the beam current, achieving the 2 kA milestone. Until recently (before 2007), the maximum beam current that was produced from the 6.5-inch diameter (612M) cathode was about 1300 A when the cathode was operating at a maximum temperature of 1140 C. At this temperature level, the heat loss was dominated by radiation which is proportional to temperature to the fourth power. The maximum operating temperature was limited by the damage threshold of the potted filament and the capacity of the filament heater power supply, as well as the shortening of the cathode life time. There were also signs of overheating at other components in the cathode assembly. Thus it was clear that our approach to increase beam current could not be simply trying to run at a higher temperature and the preferred way was to operate with a cathode that has a lower work function. The dispenser cathode initially used was the type 612M made by SpectraMat. According to the manufacturer's bulletin, this cathode should be able to produce more than 10 A/cm 2 of current density (corresponding to 2 kA of total beam current) at our operating conditions. Instead the measured emission (space charge limited) was 6 A/cm 2 . The result was similar even after we had revised the activation and handling procedures to adhere more closely to the recommend steps (taking longer time and nonstop to do the out-gassing). Vacuum was a major concern in considering the cathode's performance. Although the vacuum gauges at the injector vessel indicated 10 -8 Torr, the actual vacuum condition near the cathode in the central region of the vessel, where there might be significant out-gassing from the heater region, was never determined. Poor vacuum at the surface of the cathode degraded the emission (by raising the work function value). We reexamined

  5. Test results on prototype 50-kA conductors for tokamak induction heating coils

    Wollan, J.J.; Williamson, K.D. Jr.; Turck, B.

    1979-01-01

    Fabricability of a very large, 50-kA superconducting cable has been demonstrated. Test results of critical current and stability measurements are presented. The design critical current of 55 kA at 7 T was met. The recovery current was degraded as a result of the expectedly poor insulation system. Energy loss measurements on prototype advanced mixed matrix conductors, which will be incorporated into a second prototype cable, are presented

  6. Current status and policies on biodiesel industry in Malaysia as the world's leading producer of palm oil

    Abdullah, A.Z.; Salamatinia, B.; Mootabadi, H.; Bhatia, S.

    2009-01-01

    This article discusses current status of palm oil-based biodiesel industry in Malaysia, the policies introduced and strategies for its implementation. Due to renewability, high production rate, technical feasibility and role in reducing greenhouse gases (GHG) emission, palm oil is in the right position to supply the energy needs by the incorporation into the diesel supply. As a leading producer of palm oil, Malaysia has embarked on a comprehensive palm biofuel program since 1982. It has successfully established the use of palm biodiesel blend (B5) as a suitable fuel for the transport and industrial sectors through the introduction of the National Biofuel Policy. The current scenario of biodiesel program in Malaysia, as well as biofuel policies with respect to its use, technology, export, environmental issues and implementation aspects are thoroughly discussed. The roles of the policy towards the prosperity of the stakeholders, oil price and the reduction of greenhouse gasses are also highlighted. (author)

  7. Upgrade of the Gas Flow Control System of the Resistive Current Leads of the LHC Inner Triplet Magnets: Simulation and Experimental Validation

    Perin, A; Casas-Cubillos, J; Pezzetti, M

    2014-01-01

    The 600 A and 120 A circuits of the inner triplet magnets of the Large Hadron Collider are powered by resistive gas cooled current leads. The current solution for controlling the gas flow of these leads has shown severe operability limitations. In order to allow a more precise and more reliable control of the cooling gas flow, new flowmeters will be installed during the first long shutdown of the LHC. Because of the high level of radiation in the area next to the current leads, the flowmeters will be installed in shielded areas located up to 50 m away from the current leads. The control valves being located next to the current leads, this configuration leads to long piping between the valves and the flowmeters. In order to determine its dynamic behaviour, the proposed system was simulated with a numerical model and validated with experimental measurements performed on a dedicated test bench.

  8. Upgrade of the gas flow control system of the resistive current leads of the LHC inner triplet magnets: Simulation and experimental validation

    Perin, A.; Casas-Cubillos, J.; Pezzetti, M. [CERN, CH-1211 Geneva 23 (Switzerland); Almeida, M. [Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte (Brazil)

    2014-01-29

    The 600 A and 120 A circuits of the inner triplet magnets of the Large Hadron Collider are powered by resistive gas cooled current leads. The current solution for controlling the gas flow of these leads has shown severe operability limitations. In order to allow a more precise and more reliable control of the cooling gas flow, new flowmeters will be installed during the first long shutdown of the LHC. Because of the high level of radiation in the area next to the current leads, the flowmeters will be installed in shielded areas located up to 50 m away from the current leads. The control valves being located next to the current leads, this configuration leads to long piping between the valves and the flowmeters. In order to determine its dynamic behaviour, the proposed system was simulated with a numerical model and validated with experimental measurements performed on a dedicated test bench.

  9. Ionization Constants pKa of Cardiolipin

    Olofsson, Gerd; Sparr, Emma

    2013-01-01

    Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to differ widely with pKa1 = 2.8 and pKa2 = 7.5-9.5. Still, there are several examples of experimental ob...

  10. Theoretical estimates of supernova-neutrino cross sections for the stable even-even lead isotopes: Charged-current reactions

    Almosly, W.; Carlsson, B. G.; Suhonen, J.; Toivanen, J.; Ydrefors, E.

    2016-10-01

    A detailed study of the charged-current supernova electron neutrino and electron antineutrino scattering off the stable even-mass lead isotopes A =204 , 206, and 208 is reported in this work. The proton-neutron quasiparticle random-phase approximation (pnQRPA) is adopted to construct the nuclear final and initial states. Three different Skyrme interactions are tested for their isospin and spin-isospin properties and then applied to produce (anti)neutrino-nucleus scattering cross sections for (anti)neutrino energies below 80 MeV. Realistic estimates of the nuclear responses to supernova (anti)neutrinos are computed by folding the computed cross sections with a two-parameter Fermi-Dirac distribution of the electron (anti)neutrino energies. The computed cross sections are compared with earlier calculations and the analyses are extended to take into account the effects coming from the neutrino oscillations.

  11. Recent trends and current practices for secondary processing of zinc and lead. Part II: zinc recovery from secondary sources.

    Sahu, Kamala Kanta; Agrawal, Archana; Pandey, Banshi Dhar

    2004-08-01

    Almost all metallurgical processes are associated with the generation of wastes and residues that may be hazardous or non-hazardous in nature depending upon the criteria specified by institutions such as the US Environment Protection Agency, etc. Wastes containing heavy and toxic metals such as arsenic, cadmium, chromium, nickel, lead, copper, mercury, zinc, etc., that are present beyond permissible limits deemed to be treated or disposed of, and non-hazardous wastes can be utilized for metal recovery or safe disposal. Zinc is in growing demand all over the world. In India, a major amount of zinc is imported and therefore processing of zinc secondaries will assist in satisfying the gap between demand and supply to some extent. This report mainly focuses on the current practices and recent trends on the secondary processing of zinc. Attempts made by various laboratories to develop ecofriendly processes for the recovery of zinc from secondary raw materials are also described and discussed.

  12. Estimation of overprotection region on the painted steel plate under impressed-current cathodic protection. Gaibu dengenho ni yoru inkyoku boshoku ka no toso kohan ni okeru kaboshoku iki ni tsuite

    Iwata, M.; Huang, Y.; Fujimoto, Y. (Hiroshima Univ., hiroshima (Japan). Faculty of Engineering)

    1992-09-04

    Painting and cathodic protection are used in combination as a corrosion resisting measure for ship hull. n analytic method which uses the boundary element method for protection electric field by impressed-current method is proposed to show that rational determination is possible for the arrangement and current of the anode, and the arrangement and set voltage of the reference electrode used to control the current. However, repetitive calculation is necessary until overprotection voltage disappears from the surface of the painted steel plate while giving optional insulated area because the insulated area of adequate dimension is unknown. To decrease the number of this repetitive calculation, a study is made on a method of estimating the magnitude of the insulated area to be input as the initial value in the electric field analysis by the boundary element method. Although the insulated area has been empirically obtained, such formurization may be useful for automatic optimization using a computer of the location and number of anode, anode current, arrangement and set voltage of the reference electrode, magnitude of the insulated area, etc. in the impressed-current cathodic protection system. 2 refs., 10 figs., 1 tab.

  13. Deployable Ka-Band Reflectarray, Phase I

    National Aeronautics and Space Administration — Tyvak, in collaboration with UCLA, proposes a novel approach to the challenge of creating a large reflector for Ka-band high data rate links. We propose to attach...

  14. Exposure of Bacterial Biofilms to Electrical Current Leads to Cell Death Mediated in Part by Reactive Oxygen Species.

    Brinkman, Cassandra L; Schmidt-Malan, Suzannah M; Karau, Melissa J; Greenwood-Quaintance, Kerryl; Hassett, Daniel J; Mandrekar, Jayawant N; Patel, Robin

    2016-01-01

    Bacterial biofilms may form on indwelling medical devices such as prosthetic joints, heart valves and catheters, causing challenging-to-treat infections. We have previously described the 'electricidal effect', in which bacterial biofilms are decreased following exposure to direct electrical current. Herein, we sought to determine if the decreased bacterial quantities are due to detachment of biofilms or cell death and to investigate the role that reactive oxygen species (ROS) play in the observed effect. Using confocal and electron microscopy and flow cytometry, we found that direct current (DC) leads to cell death and changes in the architecture of biofilms formed by Gram-positive and Gram-negative bacteria. Reactive oxygen species (ROS) appear to play a role in DC-associated cell death, as there was an increase in ROS-production by Staphylococcus aureus and Staphylococcus epidermidis biofilms following exposure to DC. An increase in the production of ROS response enzymes catalase and superoxide dismutase (SOD) was observed for S. aureus, S. epidermidis and Pseudomonas aeruginosa biofilms following exposure to DC. Additionally, biofilms were protected from cell death when supplemented with antioxidants and oxidant scavengers, including catalase, mannitol and Tempol. Knocking out SOD (sodAB) in P. aeruginosa led to an enhanced DC effect. Microarray analysis of P. aeruginosa PAO1 showed transcriptional changes in genes related to the stress response and cell death. In conclusion, the electricidal effect results in death of bacteria in biofilms, mediated, at least in part, by production of ROS.

  15. Ionization constants pKa of cardiolipin.

    Gerd Olofsson

    Full Text Available Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to differ widely with pKa1 = 2.8 and pKa2 = 7.5-9.5. Still, there are several examples of experimental observations from cardiolipin-containing systems that do not fit with this dissociation behavior. Therefore, we have carried out pH-titration and titration calorimetric experiments on two synthetic cardiolipins, 1,1',2,2'-tetradecanoyl cardiolipin, CL (C14:0, and 1,1',2,2'-tetraoctadecenoyl cardiolipin, CL (C18:1. Our results show that both behave as strong dibasic acids with pKa1 about the same as the first pKa of phosphoric acid, 2.15, and pKa2 about one unit larger. The characterization of the acidic properties of cardiolipin is crucial for the understanding of the molecular organization in self-assembled systems that contain cardiolipin, and for their biological function.

  16. Ionization constants pKa of cardiolipin.

    Olofsson, Gerd; Sparr, Emma

    2013-01-01

    Cardiolipin is a phospholipid found in the inner mitochondrial membrane and in bacteria, and it is associated with many physiological functions. Cardiolipin has a dimeric structure consisting of two phosphatidyl residues connected by a glycerol bridge and four acyl chains, and therefore it can carry two negative charges. The pKa values of the phosphate groups have previously been reported to differ widely with pKa1 = 2.8 and pKa2 = 7.5-9.5. Still, there are several examples of experimental observations from cardiolipin-containing systems that do not fit with this dissociation behavior. Therefore, we have carried out pH-titration and titration calorimetric experiments on two synthetic cardiolipins, 1,1',2,2'-tetradecanoyl cardiolipin, CL (C14:0), and 1,1',2,2'-tetraoctadecenoyl cardiolipin, CL (C18:1). Our results show that both behave as strong dibasic acids with pKa1 about the same as the first pKa of phosphoric acid, 2.15, and pKa2 about one unit larger. The characterization of the acidic properties of cardiolipin is crucial for the understanding of the molecular organization in self-assembled systems that contain cardiolipin, and for their biological function.

  17. Consolidation of the 13 kA Interconnects in the LHC for Operation at 7 TeV

    Verweij, A P; Tock, J P; Willering, G P; Steckert, J; Perin, A; Scheuerlein, C; Mathot, S; Koratzinos, M; Garion, C; Denz, R; Fessia, P; Charifoulline, Z; Bertinelli, F; Sgobba, S; ten Kate, H H J

    2011-01-01

    The accident in the LHC in September 2008 occurred in an interconnection between two magnets of the 13 kA dipole circuit. Successive measurements of the resistance of other interconnects revealed other defective joints, even though the SC cables were properly connected. These defective joints are characterized by a poor bonding between the SC cable and the copper stabilizer in combination with an electrical discontinuity in the copper stabilizer. A quench at the 7-13 kA level in such a joint can lead to a fast and unprotected thermal run-away and hence opening of the circuit. It has therefore been decided to operate the LHC at a reduced and safe current of 6 kA corresponding to 3.5 TeV beam energy until all defective joints are repaired. A task force is reviewing the status of all electrical joints in the magnet circuits and preparing for the necessary repairs. The principle solution is to resolder the worst defective joints and, in addition, to apply an electrical shunt made of copper across all joints with ...

  18. New insights on water level variability for Lake Turkana for the past 15 ka and at 150 ka from relict beaches

    Forman, S. L.; Wright, D.

    2015-12-01

    Relict beaches adjacent to Lake Turkana provide a record of water level variability for the Late Quaternary. This study focused on deciphering the geomorphology, sedimentology, stratigraphy and 14C chronology of strand plain sequences in the Kalokol and Lothagam areas. Nine >30 m oscillations in water level were documented between ca. 15 and 4 ka. The earliest oscillation between ca. 14.5 and 13 ka is not well constrained with water level to at least 70 m above the present surface and subsequently fell to at least 50 m. Lake level increased to ~ 90 m between ca. 11.2 and 10.4 ka, post Younger Dryas cooling. Water level fell by >30 m by 10.2 ka, with another potential rise at ca. 8.5 ka to >70 m above current level. Lake level regressed by > 40 m at 8.2 ka coincident with cooling in the equatorial Eastern Atlantic Ocean. Two major >70 m lake level oscillations centered at 6.6 and 5.2 ka may reflect enhanced convection with warmer sea surface temperatures in the Western Indian Ocean. The end of the African Humid Period occurred from ca. 8.0 to 4.5 ka and was characterized by variable lake level (± > 40 m), rather than one monotonic fall in water level. This lake level variability reflects a complex response to variations in the extent and intensity of the East and West African Monsoons near geographic and topographic limits within the catchment of Lake Turkana. Also, for this closed lake basin excess and deficits in water input are amplified with a cascading lake effect in the East Rift Valley and through the Chew Bahir Basin. The final regression from a high stand of > 90 m began at. 5.2 ka and water level was below 20 m by 4.5 ka; and for the remainder of the Holocene. This sustained low stand is associated with weakening of the West African Monsoon, a shift of the mean position of Congo Air Boundary west of the Lake Turkana catchment and with meter-scale variability in lake level linked to Walker circulation across the Indian Ocean. A surprising observation is

  19. AltiKa: a Ka-band Altimetry Payload and System for Operational Altimetry during the GMES Period

    Jacques Verron

    2006-03-01

    Full Text Available This paper describes the Ka-band altimetry payload and system that has beenstudied for several years by CNES, ALCATEL SPACE and some science laboratories.Altimetry is one of the major elements of the ocean observing system to be madesustainable through the GEOSS (Global Earth Observation System of Systems and GMES(Global Monitoring of the Environment and Security programs. A short review of somemission objectives to be fulfilled in terms of mesoscale oceanography in the frame of theGEOSS and GMES programs is performed. To answer the corresponding requirements, theapproach consisting in a constellation of nadir altimeter is discussed. A coupled Ka-bandaltimeter-radiometer payload is then described; technical items are detailed to explain howthis payload shall meet the science and operational requirements, and expectedperformances are displayed. The current status of the payload development and flightperspectives are given.

  20. A comparison on the heat load of HTS current leads with respect to uniform and non-uniform cross-sectional areas

    Han, Seung Hak; Nam, Seok Ho; Lee, Je Yull; Song, Seung Hyun; Jeon, Hae Ryong; Baek, Geon Woo; Ko, Tae Kuk [Yonsei University, Seoul (Korea, Republic of); Kang, Hyoung Ku [Korea National University of Transportation, Chungju (Korea, Republic of)

    2017-09-15

    Current lead is a device that connects the power supply and superconducting magnets. High temperature superconductor (HTS) has lower thermal conductivity and higher current density than normal metal. For these reasons, the heat load can be reduced by replacing the normal metal of the current lead with the HTS. Conventional HTS current lead has same cross-sectional area in the axial direction. However, this is over-designed at the cold-end (4.2 K) in terms of current. The heat load can be reduced by reducing this part because the heat load is proportional to the cross-sectional area. Therefore, in this paper, heat load was calculated from the heat diffusion equation of HTS current leads with uniform and non-uniform cross-sectional areas. The cross-sectional area of the warm-end (65K) is designed considering burnout time when cooling system failure occurs. In cold-end, Joule heat and heat load due to current conduction occurs at the same time, so the cross-sectional area where the sum of the two heat is minimum is obtained. As a result of simulation, current leads for KSTAR TF coils with uniform and non-uniform cross-sectional areas were designed, and it was confirmed that the non-uniform cross-sectional areas could further reduce the heat load.

  1. ATLAS computing operations within the GridKa Cloud

    Kennedy, J; Walker, R; Olszewski, A; Nderitu, S; Serfon, C; Duckeck, G

    2010-01-01

    The organisation and operations model of the ATLAS T1-T2 federation/Cloud associated to the GridKa T1 in Karlsruhe is described. Attention is paid to Cloud level services and the experience gained during the last years of operation. The ATLAS GridKa Cloud is large and divers spanning 5 countries, 2 ROC's and is currently comprised of 13 core sites. A well defined and tested operations model in such a Cloud is of the utmost importance. We have defined the core Cloud services required by the ATLAS experiment and ensured that they are performed in a managed and sustainable manner. Services such as Distributed Data Management involving data replication,deletion and consistency checks, Monte Carlo Production, software installation and data reprocessing are described in greater detail. In addition to providing these central services we have undertaken several Cloud level stress tests and developed monitoring tools to aid with Cloud diagnostics. Furthermore we have defined good channels of communication between ATLAS, the T1 and the T2's and have pro-active contributions from the T2 manpower. A brief introduction to the GridKa Cloud is provided followed by a more detailed discussion of the operations model and ATLAS services within the Cloud.

  2. Liquid helium boil-off measurements of heat leakage from sinter-forged BSCCO current leads under DC and AC conditions

    Cha, Y.S.; Niemann, R.C.; Hull, J.R.; Youngdahl, C.A.; Lanagan, M.T.; Nakade, M.; Hara, T.

    1995-06-01

    Liquid helium boil-off experiments are conducted to determine the heat leakage rate of a pair of BSCCO 2223 high-temperature superconductor current leads made by sinter forging. The experiments are carried out in both DC and AC conditions and with and without an intermediate heat intercept. Current ranges are from 0-500 A for DC tests and 0-1,000 A rms for AC tests. The leads are self-cooled. Results show that magnetic hysteresis (AC) losses for both the BSCCO leads and the low-temperature superconductor current jumper are small for the current range. It is shown that significant reduction in heat leakage rate (liquid helium boil-off rate) is realized by using the BSCCO superconductor leads. At 100 A, the heat leakage rate of the BSCCO/copper binary lead is approximately 29% of that of the conventional copper lead. Further reduction in liquid helium boil-off rate can be achieved by using an intermediate heat intercept. For example, at 500 K, the heat leakage rate of the BSCCO/copper binary lead is only 7% of that of the conventional copper lead when an intermediate heat intercept is used

  3. A novel miniature superconducting converter for 1 kA magnets

    Chevtchenko, O.A.; Krooshoop, Hendrikus J.G.; ten Kate, Herman H.J.; Fedorovsky, Michael A.

    1996-01-01

    A miniature full-wave converter to control the current of a superconducting magnet is developed and tested in our institutes. Typical design values of the device are: AC voltage of 35 V, current of 7 A, and frequency 50-60 Hz; DC voltage o f f 0.2 V, and current of * 1 kA. An efficiency is better

  4. Advances in Ka-Band Communication System for CubeSats and SmallSats

    Kegege, Obadiah; Wong, Yen F.; Altunc, Serhat

    2016-01-01

    A study was performed that evaluated the feasibility of Ka-band communication system to provide CubeSat/SmallSat high rate science data downlink with ground antennas ranging from the small portable 1.2m/2.4m to apertures 5.4M, 7.3M, 11M, and 18M, for Low Earth Orbit (LEO) to Lunar CubeSat missions. This study included link analysis to determine the data rate requirement, based on the current TRL of Ka-band flight hardware and ground support infrastructure. Recent advances in Ka-band transceivers and antennas, options of portable ground stations, and various coverage distances were included in the analysis. The link/coverage analysis results show that Cubesat/Smallsat missions communication requirements including frequencies and data rates can be met by utilizing Near Earth Network (NEN) Ka-band support with 2 W and high gain (>6 dBi) antennas.

  5. HTS power leads for the BTEV interaction region

    Feher, S.; Carcagno, R.; Orris, D.; Page, T.; Pischalnikov, Y.; Rabehl, R.; Sylvester, C.; Tartaglia, M.; Tompkins, J.C.; /Fermilab

    2005-05-01

    A new Interaction Region (IR) for the BTEV experiment was planned to be built at Fermilab. This IR would have required new superconducting quadrupole magnets and many additional power circuits for their operation. The new ''low beta'' quadrupole magnet design was based upon the Fermilab LHC quadrupole design, and would have operated at 9.56 kA in 4.5 K liquid helium. The use of conventional power leads for these circuits would have required substantially more helium for cooling than is available from the cryogenic plant, which is already operating close to its limit. To decrease the heat load and helium cooling demands, the use of HTS power leads was necessary. In developing specifications for HTS leads for the BTEV interaction region, several 6 kA HTS leads produced by American Superconductor Corporation (ASC) have been tested at over-current conditions. Final design requirements were to be based on these test results. This paper summarizes the test results and describes the design requirements for the 9.65 kA HTS power leads.

  6. HTS power leads for the BTEV interaction region

    Feher, S.; Carcagno, R.; Orris, D.; Page, T.; Pischalnikov, Y.; Rabehl, R.; Sylvester, C.; Tartaglia, M.; Tompkins, J.C.

    2005-01-01

    A new Interaction Region (IR) for the BTEV experiment was planned to be built at Fermilab. This IR would have required new superconducting quadrupole magnets and many additional power circuits for their operation. The new ''low beta'' quadrupole magnet design was based upon the Fermilab LHC quadrupole design, and would have operated at 9.56 kA in 4.5 K liquid helium. The use of conventional power leads for these circuits would have required substantially more helium for cooling than is available from the cryogenic plant, which is already operating close to its limit. To decrease the heat load and helium cooling demands, the use of HTS power leads was necessary. In developing specifications for HTS leads for the BTEV interaction region, several 6 kA HTS leads produced by American Superconductor Corporation (ASC) have been tested at over-current conditions. Final design requirements were to be based on these test results. This paper summarizes the test results and describes the design requirements for the 9.65 kA HTS power leads

  7. Muukeelne elanikkond vajab ka ETVd / Ela Tomson

    Tomson, Ela, 1945-

    2006-01-01

    Ilmunud ka: Postimees : na russkom jazõke 4. juuli lk. 7, Pjarnuskii Ekspress 7. juuli lk. 7. Autori arvates on riik jätnud Eestis elava muukeelse elanikkonna Venemaa telekanalite mõju alla. Ometi poleks see, kui varustada ETV tähtsamad saated venekeelsete subtiitritega, midagi rahamahukat ja kaelamurdvat

  8. Jaapani edumetoodika ka Eestis / Merike Lees

    Lees, Merike, 1976-

    2004-01-01

    Ilmunud ka: Delovõje Vedomosti 17. nov. lk. 28. Tootmissfääris kasutatavast Jaapani 20 võtme metoodikast loodab ettevõttele kasu saada lehtmetalli töötleva AS-i Favor Metaform nõukogu esimees Almar Proosi. Lisa: Mis on 20 võtit?

  9. Ka-band waveguide rotary joint

    Yevdokymov, Anatoliy; Sirenko, Kostyantyn; Kryzhanovskiy, Volodymyr; Pazynin, Vadim

    2013-01-01

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three

  10. Drastic lake level changes of Lake Van (eastern Turkey) during the past ca. 600 ka: climatic, volcanic and tectonic control

    Cukur, D.; Krastel, S.; Schmincke, H.; Sumita, M.; Tomonaga, Y.; Damci, E.

    2013-12-01

    Lake Van is the largest soda lake in the world with a present surface of 3,574 km2 and a maximum water depth of 450 m. Sedimentary deposits in the lake preserve one of the most complete record of continental climate in the Middle East since the Middle Pleistocene. We studied these deposits to characterize the evolution of the lake level and its possible relationships with changes in climate, volcanic, and regional tectonics since the formation of the lake ca. 600 ka ago. Changes in lake level were determined based on high-resolution seismic reflection profiles showing erosional surfaces, changes in stratal geometries such as downward shifts in coastal onlap, and recognition of distinctive stratigraphic features such as prograding delta clinoforms. Our results show that Lake Van has undergone drastic changes in surface elevation by as much as 600 meters over the past ca. 600 ka. Five major lowstands occurred at ca. ~600 ka, ca. 365-340 ka, ca 290-230 ka; ca. 150-130 ka; and ca. 30-14 ka. During a first period (A) (ca. 600-ca 230 ka) lake levels changed drastically by hundreds of m but at longer time intervals between low and high stands. Changes occurred more frequently but mostly by a few tens of m during the past ca. 230 ka years where we can distinguish a first period (B1) of stepwise transgressions between ca. 230 and 150 ka followed by a short regression between ca. 150 and 130 ka. Lake level rose stepwise again during period B2 lasting until ca 30 ka. During the past 30 ka a regression and a final transgression each lasted ca. 15 ka years. The major lowstand periods in Lake Van occurred during glacial periods, arguing for a climatic control of these lake-level fluctuations (i.e., significantly reduced precipitation leading to lake level low stands). Although climate forcing may have been the dominant cause for the drastic lake level changes of Lake Van, volcanic and tectonic forcing factors are also invoked. For example, the number of distinct tephra layers

  11. Ka-band SAR interferometry studies for the SWOT mission

    Fernandez, D. E.; Fu, L.; Rodriguez, E.; Hodges, R.; Brown, S.

    2008-12-01

    The primary objective of the NRC Decadal Survey recommended SWOT (Surface Water and Ocean Topography) Mission is to measure the water elevation of the global oceans, as well as terrestrial water bodies (such as rivers, lakes, reservoirs, and wetlands), to answer key scientific questions on the kinetic energy of ocean circulation, the spatial and temporal variability of the world's surface freshwater storage and discharge, and to provide societal benefits on predicting climate change, coastal zone management, flood prediction, and water resources management. The SWOT mission plans to carry the following suite of microwave instruments: a Ka-band interferometer, a dual-frequency nadir altimeter, and a multi-frequency water-vapor radiometer dedicated to measuring wet tropospheric path delay to correct the radar measurements. We are currently funded by the NASA Earth Science Technology Office (ESTO) Instrument Incubator Program (IIP) to reduce the risk of the main technological drivers of SWOT, by addressing the following technologies: the Ka-band radar interferometric antenna design, the on-board interferometric SAR processor, and the internally calibrated high-frequency radiometer. The goal is to significantly enhance the readiness level of the new technologies required for SWOT, while laying the foundations for the next-generation missions to map water elevation for studying Earth. The first two technologies address the challenges of the Ka-band SAR interferometry, while the high- frequency radiometer addresses the requirement for small-scale wet tropospheric corrections for coastal zone applications. In this paper, we present the scientific rational, need and objectives behind these technology items currently under development.

  12. Features of the low-power charge controller of lead-acid current sources charged by solar batteries

    Tukfatullin, O.F.; Yuldoshev, I.A.; Solieva, N.A.

    2008-01-01

    Influence of different factors on exploitations characteristics of solar photoelectric plant is investigated by field-performance data. A construction of charge controller of the lead-acid accumulator battery charging by means of solar battery is analyzed taking into account these factors. (authors)

  13. Early response to sibutramine in patients not meeting current label criteria: preliminary analysis of SCOUT lead-in period

    Caterson, Ian; Coutinho, Walmir; Finer, Nick

    2010-01-01

    pulse rate increases; median 1.5 bpm (nonconformers) vs. 3.0 bpm (conformers). There was a low incidence of serious adverse events (conformers: 1.0%; nonconformers: 2.8%) and ~93% of patients in both groups completed the 6-week period. The SCOUT lead-in period evaluating weight management...

  14. Precision Deployable Mast for the SWOT KaRIn Instrument

    National Aeronautics and Space Administration — Design and prototype a lightweight, precision-deployable mast for the Ka-band Radar Interferometer (KaRIn) antennas in the Surface Water and Ocean Topography (SWOT)...

  15. Ka-Band, Multi-Gigabit-Per-Second Transceiver

    Simons, Rainee N.; Wintucky, Edwin G.; Smith, Francis J.; Harris, Johnny M.; Landon, David G.; Haddadin, Osama S.; McIntire, William K.; Sun, June Y.

    2011-01-01

    A document discusses a multi-Gigabit-per-second, Ka-band transceiver with a software-defined modem (SDM) capable of digitally encoding/decoding data and compensating for linear and nonlinear distortions in the end-to-end system, including the traveling-wave tube amplifier (TWTA). This innovation can increase data rates of space-to-ground communication links, and has potential application to NASA s future spacebased Earth observation system. The SDM incorporates an extended version of the industry-standard DVB-S2, and LDPC rate 9/10 FEC codec. The SDM supports a suite of waveforms, including QPSK, 8-PSK, 16-APSK, 32- APSK, 64-APSK, and 128-QAM. The Ka-band and TWTA deliver an output power on the order of 200 W with efficiency greater than 60%, and a passband of at least 3 GHz. The modem and the TWTA together enable a data rate of 20 Gbps with a low bit error rate (BER). The payload data rates for spacecraft in NASA s integrated space communications network can be increased by an order of magnitude (>10 ) over current state-of-practice. This innovation enhances the data rate by using bandwidth-efficient modulation techniques, which transmit a higher number of bits per Hertz of bandwidth than the currently used quadrature phase shift keying (QPSK) waveforms.

  16. Eolian depositional phases during the past 50 ka and inferred climate variability for the Pampean Sand Sea, western Pampas, Argentina

    Tripaldi, Alfonsina; Forman, Steven L.

    2016-05-01

    The Pampean Sand Sea, which occurs from the Argentinian Pampas to the eastern Andean piedmont, hosts presently stabilized dune fields spanning the late Quaternary. This study integrates previous results and presents new geomorphic, stratigraphic, sedimentological, and chronologic data for nineteen >2 m-thick eolian successions for the San Luis paleo-dune field, western Pampas, to better constrain the depositional history. Six eolian depositional phases are identified spanning the past 50 ka, interposed with paleosols and/or bounded by erosive surfaces. Age control was from 61 OSL ages of small aliquots of quartz grains from eolian stratigraphic units. The inferred timing of eolian phases are at ca. 70 ± 10 yr, 190 ± 20 yr, 12 to 1 ka, 22 to 17 ka, 29 to 24 ka, and 40 to 32 ka. A maximum span for periods of pedogenesis at ca. 12 to 17 ka, 22 to 24 ka, and 29 to 32 ka was provided by bounding OSL ages, which broadly overlap with high stands of pluvial lakes and glacier advances in the central Andes. We infer that the added precipitation may reflect expansion of the Southern Hemisphere monsoon, associated with Northern Hemisphere Heinrich events, leading to episodes of significantly wetter conditions (>350 mm MAP) to at least 35° S. Most of the Holocene (12 ka to 0.8 ka) was characterized by sand sheet deposit under drier than present conditions (100-450 mm MAP), associated with Monte-type vegetation (shrub steppe). The latest two eolian depositional phases, occurred at ca. 190 and 70 yr ago, during the historic period with European settlement and are related to anthropogenic landscape disturbance, though the youngest phase was concomitant with 1930s drought. Wet conditions dominated since ca. AD 1970 with new lakes and rivers forming across this eolian terrain; an incongruous environmental response in reference to drier conditions for most of the Holocene.

  17. Ka-band Technologies for Small Spacecraft Communications via Relays and Direct Data Downlink

    Budinger, James M.; Niederhaus, Charles; Reinhart, Richard; Downey, Joe; Roberts, Anthony

    2016-01-01

    As the scientific capabilities and number of small spacecraft missions in the near Earth region increase, standard yet configurable user spacecraft terminals operating in Ka-band are needed to lower mission cost and risk and enable significantly higher data return than current UHF or S-band terminals. These compact Ka-band terminals are intended to operate with both the current and next generation of Ka-band relay satellites and via direct data communications with near Earth tracking terminals. This presentation provides an overview of emerging NASA-sponsored and commercially provided technologies in software defined radios (SDRs), transceivers, and electronically steered antennas that will enable data rates from hundreds of kbps to over 1 Gbps and operate in multiple frequency bands (such as S- and X-bands) and expand the use of NASA's common Ka-bands frequencies: 22.55-23.15 GHz for forward data or uplink; and 25.5-27.0 GHz for return data or downlink. Reductions in mass, power and volume come from integration of multiple radio functions, operations in Ka-band, high efficiency amplifiers and receivers, and compact, flat and vibration free electronically steered narrow beam antennas for up to + 60 degrees field of regard. The software defined near Earth space transceiver (SD-NEST) described in the presentation is intended to be compliant with NASA's space telecommunications radio system (STRS) standard for communications waveforms and hardware interoperability.

  18. Current studies on bacterospermia the leading cause of male infertility: a prot?g? and potential threat towards mans extinction

    Isaiah, Ibeh Nnana; Nche, Bikwe Thomas; Nwagu, Ibeh Georgina; Nnanna, Ibeh Isaiah

    2011-01-01

    Background: The current rise of male infertility associated with bacterospermia and urogenital infection has been on the increase amongst adult married males in Benin metropolis and a major cause of concern to male fertility and reproduction in Nigeria. Aim: To microbiologically isolate and study the infectious agent that has led to male infertility and also to study the percentage occurrence of bacteropsermia and urogenital caused infertility in adult married males in Benin metropolis Materi...

  19. Insulation model of power lead for 66 kV class superconducting fault current limiter; Chodendo genryuki denryu rido yo zetsuen no kaihatsu

    Sakai, M.; Fukuda, A.; Shimada, M.; Urata, M. [Toshiba Corp., Tokyo (Japan); Okuma, T.; Sato, Y.; Iwata, Y. [Tokyo Electric Power Co. Ink., Tokyo (Japan)

    1999-06-07

    We advance the development of high-temperature superconductivity current limiter using the normal conduction transition. Since the rated voltage is high with 66kV, we desire that solid insulation which consists of main insulating layer and multiple layers in semiconductive layer is conducted to the current lead which connects the ordinary temperature and very low temperature division. And, it is necessary to sufficiently decrease the void, since crack proof and dielectric strength lower, when large bubble exists in the main insulating layer. We use ethylene propylene rubber for the solid insulation of superconducting cable. Though filler has entered the EP-rubber, the formability lowers, when we put filler in, and the void becomes easy to be generated. Then, we produced the current lead insulation model using the EP-rubber without filler, and we carried out crack-resistant test and withstand voltage test. (NEDO)

  20. Quench characteristics of Ag/AuBi2223 HTS-stainless steel stack used for the hybrid current leads of the large hadron collider

    Al-Mosawi, M K; Beduz, C; Yang, Y; Ballarino, A

    2008-01-01

    The quench characteristics of Ag/Au sheathed Bi2223 tapes have been investigated in an adiabatic condition and in a configuration similar to that used in hybrid high temperature superconducting current leads, namely the 13000A leads used for the Large Hadron Collider at CERN. A specialised rig was designed and constructed to provide a carefully controlled environment. The samples were prepared from HTS tape soldered onto a stainless steel substrate with a number of temperature sensors at various positions along the length of tape. One end of the lead (cold end) was maintained at 6K using G-M cryo-cooler whereas the temperature of the other end (warm end) can be varied and maintained at temperatures up to 100K. The thermal runaway currents (quench currents) at various warm end temperatures (in the range of 40-100K) were determined. The temperature evolutions at various locations along the tape were recorded at different top end temperatures and currents. The effect of the stainless steel mechanical reinforceme...

  1. Ka-band waveguide rotary joint

    Yevdokymov, Anatoliy

    2013-04-11

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three circular choke grooves. Utilisation of three choke grooves allows larger operating clearance. Two prototypes of the rotary joint have been manufactured and experimentally studied. The observed loss is from 0.4 to 0.8 dB in 1.5 GHz band.

  2. Bohorodyts'ka and Starosamars'ka hundred (sotnya: administrative system and officer (starshyna corps

    Repan, O. A.

    2017-12-01

    Full Text Available Bohorodyts'ka and Starosamars'ka hundred (sotnyais an unique Cossack formations. They existed in a territorial isolation from the Hetmanate and Slobozhanshchyna, on the lands of the Zaporozhian Sich. The study of these formations will better understand the policy of the Russian government in relation to the Sich, to find out the methods by which the state authorities planned to put Zaporizhzhya Cossacks under their control. We do not know when the Bohorodyts'ka hundred (sotnya arose. Now the first mention in the documents dates back to 1700. The Russian government planned to create a Cossack regiment (polk here, but in reality was founded a Cossack hundred (sotnya. Ivan Mazepa, as an autonomous ruler, wanted to include this formation in the structure of Hetmanate, but a hundred (sotnya was subject to the authority of a representative of the Russian administration – the Kiev governor. The hundreds (sotnya were liquidated as a result of Russia's defeat in the war with Turkey and the signing of the Prut peace in 1711. We do not know when the Cossack hundred (sotnya was restored under the name Starosamars'ka. This happened in the late 1730s – early 1740s. In 1744, the Starosamarsʼka hundreds became part of the Poltava regiment (polk of the Hetmanate. The administrative apparatus of the hundreds was predominantly similar to other hundreds of Hetmanates, but the real power of the Cossack officers was a bit lower here. During the existence of the Starosamars'ka hundreds, such a body of self-government was preserved as a council (rada that was not typical for the Hetmanate in this period. This was due to the fact that the peoples could easily escape from their power and move to neighboring settlements and recognize the jurisdiction of the Zaporozhska Sich. The population of hundreds and officers consisted mainly of immigrants from the left bank of the Dnieper, to a lesser extent – from immigrants from the right bank. Summing up, I note that the

  3. Low AC Loss in a 3 kA HTS Cable of the Dutch Project

    Chevtchenko, Oleg; Zuijderduin, Roy; Smit, Johan; Willén, Dag; Lentge, Heidi; Thidemann, Carsten; Traeholt, Chresten; Melnik, Irina; Geschiere, Alex

    Requirements for a 6 km long high temperature superconducting (HTS) AC power cable of the Amsterdam project are: a cable has to fit in an annulus of 160 mm, with two cooling stations at the cable ends only. Existing solutions for HTS cables would lead to excessively high coolant pressure drop in the cable, potentially affecting public acceptance of the project. A way out would be to substantially reduce AC losses from 1 down to about 0.1 W/m per phase at rated current of 3 kArms, frequency of 50 Hz and temperature of 77 K. In this paper we discuss a strategy towards this ambitious goal, a concept design of the single phase cable 3 kA conductor made of YBCO tapes and present corresponding experimental and simulation data supporting the developed approach leading directly to this goal. HTS cable model was made that show a drastically reduced AC loss. The low loss was achieved by using appropriate pitch angles for two-layer cable conductor of relatively large diameter, by minimizing the gaps between the HTS tapes, and by using narrow HTS tapes that conform well to the roundness of the underlying former. AC loss of 0.12 W/m at 3 kArms was measured at a frequency of 60 Hz and at a temperature of 77 K.

  4. TRADITIONAL RURAL WETLANDS IN HARYANA STATE OF INDIA ARE CURRENTLY CONFRONTING MULTICORNERED THREATS LEADING TO EXTINCTION SOONER THAN LATER

    Rohtash chand Gupta

    2012-05-01

    Full Text Available The most serious threat to traditional rural ponds in Haryana is associated with transformed societal behavioural patterns, ethics, values and life style, amongst several others. The siltation of ponds with adjoining areas, soil coming in with rain water is a very serious cause of stratification of rural ponds. Also contracting of village community land for sun drying of cow dung cakes inspires villagers to overload periphery of each pond with cow dung turning the premises into grave-yard of dung. This dung is the major source of polluting pond water into blackish water with high load of organic matter. Moreover, it leads to over excessive eutrophication. Building of major highways and connectivity roads have resulted into compartmentalization and degradation of village ponds. Inhabitation of peripheral village ponds boundaries by lower section of society for dwelling purposes is more threat to wetlands. The indifferent inclination of villagers towards silted ponds drenched in bad odour and blackish sludge is the story of 80% of the cases. The total blockage of run-off rainy water towards the natural age old rural ponds due to obstruction by way of human inhabitation has resulted into desertification of shallow water sheet in 90% of the cases. The oblivion of harvesting dried silt in summer for brick making has spelled doom for the ponds turning them into flat ground through successive decades and so on. The water quality in all ponds was overshooting the decaying stage due to the continuous mixing of cow dung drenched rainy water. Over excessive usage of ponds for bathing of cattle, dumping of cow dung and rotten vegetables waste has turned ponds into live sinks of dirt, garbage and rural dairy wastes. Majority of village ponds are now out of existence or in deep black sludge laden or converted into Fish-Farming wetlands. The present studies have indicated that Winter migratory birds like Greylag Goose Anser anser, Bar-headed Goose Anser

  5. Development of Methods for the Determination of pKa Values

    Reijenga, Jetse; van Hoof, Arno; van Loon, Antonie; Teunissen, Bram

    2013-01-01

    The acid dissociation constant (pKa) is among the most frequently used physicochemical parameters, and its determination is of interest to a wide range of research fields. We present a brief introduction on the conceptual development of pKa as a physical parameter and its relationship to the concept of the pH of a solution. This is followed by a general summary of the historical development and current state of the techniques of pKa determination and an attempt to develop insight into future developments. Fourteen methods of determining the acid dissociation constant are placed in context and are critically evaluated to make a fair comparison and to determine their applications in modern chemistry. Additionally, we have studied these techniques in light of present trends in science and technology and attempt to determine how these trends might affect future developments in the field. PMID:23997574

  6. Probability of burn-through of defective 13 kA splices at increased energy levels

    Verweij, A

    2011-01-01

    In many 13 kA splices in the machine there is a lack of bonding between the superconducting cable and the stabilising copper along with a bad contact between the bus stabiliser and the splice stabiliser. In case of a quench of such a defective splice, the current cannot bypass the cable through the copper, hence leading to excessive local heating of the cable. This may result in a thermal runaway and burn-through of the cable in a time smaller than the time constant of the circuit. Since it is not possible to protect against this fast thermal run-away, one has to limit the current to a level that is small enough so that a burn-through cannot occur. Prompt quenching of the joint, and quenching due to heat propagation through the bus and through the helium are considered. Probabilities for joint burn-through are given for the RB circuit for beam energies of 3.5, 4 and 4.5 TeV, and a decay time constant of the RB circuit of 50 and 68 s.

  7. HTS Power Leads for the BTeV Interaction Region

    Feher, Sandor; Orris, Darryl; Pishchalnikov, Yu M; Rabehl, Roger Jon; Sylvester, C D; Tartaglia, M; Tompkins, John

    2005-01-01

    A new Interaction Region for the BTEV experiment is planned to be built soon at Fermilab. This IR will require new superconducting quadrupole magnets and many additional power circuits for their operation. The new "low beta" quadupole magnet design is based upon the Fermilab LHC quadrupole design, and will operate at 9.56 kA in 4.5 K liquid helium. The use of conventional power leads for these circuits would require substantially more helium for cooling than is available from the cryogenic plant, which is already operating close to its limit. To decrease the heat load and helium cooling demands, the use of HTS power leads is necessary. Fermilab is in the process of procuring HTS leads for this new interaction region. Several 6 kA HTS leads produced by American Superconductor Corporation have been tested at over-current conditions. Based on the test results, design requirements are being developed for procuring the HTS current leads. This paper summarizes the test results and describes the design requirements ...

  8. High Efficiency Ka-Band Spatial Combiner

    D. Passi

    2014-12-01

    Full Text Available A Ka-Band, High Efficiency, Small Size Spatial Combiner (SPC is proposed in this paper, which uses an innovatively matched quadruple Fin Lines to microstrip (FLuS transitions. At the date of this paper and at the Author's best knowledge no such FLuS innovative transitions have been reported in literature before. These transitions are inserted into a WR28 waveguide T-junction, in order to allow the integration of 16 Monolithic Microwave Integrated Circuit (MMIC Solid State Power Amplifiers (SSPA's. A computational electromagnetic model using the finite elements method has been implemented. A mean insertion loss of 2 dB is achieved with a return loss better the 10 dB in the 31-37 GHz bandwidth.

  9. A ~400 ka supra-Milankovitch cycle in the Na, Mg, Pb, Ni, and Co records of a ferromanganese crust from the Vityaz fracture zone, central Indian ridge.

    Banerjee, R.; Gupta, S.M.; Miura, H.; Borole, D.V.

    A approx. 400 ka (kilo years) supra-Milankovitch cycle, recorded in the sodium, magnesium, lead, nickel and cobalt contents of a 32mm thick ferromanganese crust from Vityaz fracture zone, central Indian ridge is reported here. To arrive...

  10. Preliminary analysis of accident in SST-1 current feeder system

    Roy, Swati; Kanabar, Deven; Garg, Atul; Singh, Amit; Tanna, Vipul; Prasad, Upendra; Srinivasan, R.

    2017-01-01

    Steady-state Tokamak-1 (SST-1) has 16 superconducting Toroidal field (TF) and 9 superconducting poloidal field (PF) coils rated for 10kA DC. All the TF are connected in series and are operated in DC condition whereas PF coils are individually operated in pulse mode during SST-1 campaigns. SST-1 current feeder system (CFS) houses 9 pairs of PF current leads and 1 pair of TF current leads. During past SST-1 campaign, there were arcing incidents within SST-1 CFS chamber which caused significant damage to PF superconducting current leads as well as its Helium cooling lines of the current leads. This paper brings out the preliminary analysis of the mentioned arcing incident, possible reasons and its investigation thereby laying out the sequence of events. From this analysis and observations, various measures to avoid such arcing incidents have also been proposed. (author)

  11. Quench Propagation in the Superconducting 6 kA Flexible Busbars of the LHC

    Calvi, M; Herzog, R; Pelegrin-Carcelen, J M; Sonnemann, F

    2001-01-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recom...

  12. Superconducting current transducer

    Kuchnir, M.; Ozelis, J.P.

    1990-10-01

    The construction and performance of an electric current meter that operates in liquid He and mechanically splits apart to permit replacement of the current carrying conductor is described. It permits the measurement of currents induced in a loop of superconducting cable and expeditious exchange of such loops. It is a key component for a short sample cable testing facility that requires no high current power supplies nor high current leads. Its superconducting pickup circuit involves a non-magnetic core toroidal split-coil that surrounds the conductor and a solenoid whose field is sensed by a Hall probe. This toroidal split-coil is potted inside another compensating toroidal split-coil. The C shaped half toroids can be separated and brought precisely together from outside the cryostat. The Hall probe is energized and sensed by a lock-in amplifier whose output drives a bipolar power supply which feeds the compensating coil. The output is the voltage across a resistor in this feedback circuit. Currents of up to 10 kA can be measured with a precision of 150 mA. 3 refs., 4 figs

  13. Electrostatic contribution of surface charge residues to the stability of a thermophilic protein: benchmarking experimental and predicted pKa values.

    Chi-Ho Chan

    Full Text Available Optimization of the surface charges is a promising strategy for increasing thermostability of proteins. Electrostatic contribution of ionizable groups to the protein stability can be estimated from the differences between the pKa values in the folded and unfolded states of a protein. Using this pKa-shift approach, we experimentally measured the electrostatic contribution of all aspartate and glutamate residues to the stability of a thermophilic ribosomal protein L30e from Thermococcus celer. The pKa values in the unfolded state were found to be similar to model compound pKas. The pKa values in both the folded and unfolded states obtained at 298 and 333 K were similar, suggesting that electrostatic contribution of ionizable groups to the protein stability were insensitive to temperature changes. The experimental pKa values for the L30e protein in the folded state were used as a benchmark to test the robustness of pKa prediction by various computational methods such as H++, MCCE, MEAD, pKD, PropKa, and UHBD. Although the predicted pKa values were affected by crystal contacts that may alter the side-chain conformation of surface charged residues, most computational methods performed well, with correlation coefficients between experimental and calculated pKa values ranging from 0.49 to 0.91 (p<0.01. The changes in protein stability derived from the experimental pKa-shift approach correlate well (r = 0.81 with those obtained from stability measurements of charge-to-alanine substituted variants of the L30e protein. Our results demonstrate that the knowledge of the pKa values in the folded state provides sufficient rationale for the redesign of protein surface charges leading to improved protein stability.

  14. Assigning the pKa's of Polyprotic Acids.

    Bodner, George M.

    1986-01-01

    Discusses (1) polyproptic acids for which the difference between K-a's is large; (2) the Henderson-Hasselbach equation; (3) polyprotic acids for which the difference between K-a's is small; (4) analysis of microscopic dissociation constants for cysteine; and (5) analysis of pK-a data. (JN)

  15. Briti korruptsioonivastane seadus kehtib ka Eestis / Tõnis Tamme

    Tamme, Tõnis, 1972-

    2011-01-01

    Suurbritannias jõustub 1. juulil 2011 uus korruptsioonivastane seadus (Bribery Act 2010), mis kehtib ühtmoodi nii Briti ettevõtetele kui ka mujal maailmas asutatud äriühingutele, kelle äritegevus või ka osa sellest omab puutumust Suurbritanniaga

  16. Ulukiliha sobib ka jõululauale / Raivo Feldmann

    Feldmann, Raivo

    2009-01-01

    Adavere lihakauplusest, mida on külastanud ka president Toomas Hendrik Ilves ja proua Evelin Ilves. OÜ Chef Foodsi kaupa tellib ka presidendi kantselei. Juuresoleval fotol president Toomas Hendrik Ilves ja proua Evelin Ilves koos OÜ Chef Foodsi juhatuse liikme Veiko Villemi ja juhataja Priit Noorhaniga

  17. Comparison of AltiKa and CryoSat-2 Elevation and Elevation Rates over the Amundsen Sea Sector

    Otosaka, I.; Shepherd, A.; Hogg, A.

    2017-12-01

    Altimeters have been successfully used for more than two decades to observe changes in the ice sheet surface and to estimate the contribution of ice sheets to sea level rise. The Satellite for Argos and AltiKa (SARAL) was launched in February 2013 as a joint mission between the French space agency (CNES) and the Indian Space Research Organisation (ISRO). While the altimeters previously launched into space are operating at Ku-band (13.6 GHz), the altimeter on board SARAL, AltiKa, is the first instrument to operate at Ka-band (36.8 GHz). The higher frequency of AltiKa is expected to lead to reduced penetration of the radar signal into the snowpack, compared to Ku-band. A comparison of ice sheet elevation measurements recorded at the two frequencies may therefore provide useful information on surface and its scattering properties. In this study, we compare elevation and elevation rates recorded by AltiKa and CryoSat-2 between March 2013 and April 2017 over the Amundsen Sea Sector (ASS), one of the most rapidly changing sectors of West Antarctica. Elevation and elevation rates are computed within 5 km grid cells using a plane fit method, taking into account the contributions of topography and fluctuations in elevation and backscatter. The drifting orbit and imaging modes of CryoSat-2 result in 78,7 % sampling of the study area, whereas AltiKa samples 39,7 % due to its sparser orbit pattern and due to loss of signal in steeply sloping coastal margins. Over the study period, the root mean square difference between elevation and elevation change recorded at Ka-band and Ku-band were 40.3 m and 0.54 m/yr, respectively. While the broad spatial pattern of elevation change is well resolved by both satellites, data gaps along the Getz coastline may be partly responsible for the lower elevation change rate observed at Ka-band. We also compared CryoSat-2 and AltiKa to coincident airborne data from NASA's Operation IceBridge (OIB). The mean difference of elevation rate between

  18. Neutral currents

    Aubert, B.

    1994-11-01

    The evidence for the existence of weak neutral current has been a very controverted topics in the early 1970's, as well as the muon did in the 1930's. The history is very rich considering the evolution of the experimental techniques in high energy particle physics. The history of the discovery and the study of weak neutral current is reviewed. Later the quest of the intermediate vector boson continues with the decision of the community to build a large proton antiproton collider. (K.A.). 14 refs., 1 fig

  19. Surface Morphology Study of Nanostructured Lead-Free Solder Alloy Sn-Ag-Cu Developed by Electrodeposition: Effect of Current Density Investigation

    Sakinah Mohd Yusof

    2013-10-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Nanostructured lead-free solder Sn-Ag-Cu (SAC was developed by electrodeposition method at room temperature. Electrolite bath which comprised of the predetermined quantity of tin methane sulfonate, copper sulfate and silver sulfate were added sequentially to MSA solution. The methane sulphonic acid (MSA based ternary Sn-Ag-Cu bath was developed by using tin methane sulfonate as a source of Sn ions while the Cu+ and Ag+ ions were obtained from their respective sulfate salts. The rate of the electrodeposition was controlled by variation of current density. The addition of the buffer, comprising of sodium and ammonium acetate helped in raising the pH solution. During the experimental procedure, the pH of solution, composition of the electrolite bath, and the electrodeposition time were kept constant. The electrodeposited rate, deposit composition and microstructure were investigated as the effect of current density. The electrodeposited solder alloy was characterized for their morphology using Field Emission Scanning Electron Microscope (FESEM. In conclusion, vary of current density will play significant role in the surface morphology of nanostructured lead-free solder SAC developed. Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New

  20. Thickness dependence of the poling and current-voltage characteristics of paint films made up of lead zirconate titanate ceramic powder and epoxy resin

    Egusa, Shigenori; Iwasawa, Naozumi

    1995-11-01

    A specially prepared paint made up of lead zirconate titanate (PZT) ceramic powder and epoxy resin was coated on an aluminum plate and was cured at room temperature, thus forming the paint film of 25-300 μm thickness with a PZT volume fraction of 53%. The paint film was then poled at room temperature, and the poling behavior was determined by measuring the piezoelectric activity as a function of poling field. The poling behavior shows that the piezoelectric activity obtained at a given poling field increases with an increase in the film thickness from 25 to 300 μm. The current-voltage characteristic of the paint film, on the other hand, shows that the increase in the film thickness leads not only to an increase in the magnitude of the current density at a given electric field but also to an increase in the critical electric field at which the transition from the ohmic to space-charge-limited conduction takes place. This fact indicates that the amount of the space charge of electrons injected into the paint film decreases as the film thickness increases. Furthermore, comparison of the current-voltage characteristic of the paint film with that of a pure epoxy film reveals that the space charge is accumulated largely at the interface between the PZT and epoxy phases in the paint film. On the basis of this finding, a model is developed for the poling behavior of the paint film by taking into account a possible effect of the space-charge accumulation and a broad distribution of the electric field in the PZT phase. This model is shown to give an excellent fit to the experimental data of the piezoelectric activity obtained here as a function of poling field and film thickness.

  1. The sensitivity of the Late Saalian (140 ka) and LGM (21 ka) Eurasian ice sheets to sea surface conditions

    Colleoni, Florence [Centro Euro-Mediterraneo per i Cambiamenti Climatici, Bologna (Italy); UJF, CNRS, Laboratoire de Glaciologie et Geophysique de l' Environnement, Saint Martin d' Heres Cedex (France); Stockholm University, Department of Geological Sciences, Stockhlom (Sweden); Liakka, Johan [Stockholm University, Department of Meteorology, Stockholm (Sweden); Krinner, Gerhard; Peyaud, Vincent [UJF, CNRS, Laboratoire de Glaciologie et Geophysique de l' Environnement, Saint Martin d' Heres Cedex (France); Jakobsson, Martin [Stockholm University, Department of Geological Sciences, Stockhlom (Sweden); Masina, Simona [Centro Euro-Mediterraneo per i Cambiamenti Climatici, Istituto Nazionale di Geofisica e Vulcanologia, Bologna (Italy)

    2011-08-15

    This work focuses on the Late Saalian (140 ka) Eurasian ice sheets' surface mass balance (SMB) sensitivity to changes in sea surface temperatures (SST). An Atmospheric General Circulation Model (AGCM), forced with two preexisting Last Glacial Maximum (LGM, 21 ka) SST reconstructions, is used to compute climate at 140 and 21 ka (reference glaciation). Contrary to the LGM, the ablation almost stopped at 140 ka due to the climatic cooling effect from the large ice sheet topography. Late Saalian SST are simulated using an AGCM coupled with a mixed layer ocean. Compared to the LGM, these 140 ka SST show an inter-hemispheric asymmetry caused by the larger ice-albedo feedback, cooling climate. The resulting Late Saalian ice sheet SMB is smaller due to the extensive simulated sea ice reducing the precipitation. In conclusion, SST are important for the stability and growth of the Late Saalian Eurasian ice sheet. (orig.)

  2. A Uranium-Lead Chronology of Speleothem Deposition in the Canadian Arctic

    Gambino, C.; Shakun, J. D.; McGee, D.; Ramezani, J.; Khadivi, S.; Wong, C. I.

    2017-12-01

    The Artic is one of the fastest warming regions on the planet. Currently much of the Arctic is covered by permafrost, which contains approximately 1,700 gigatons of organic carbon. Permafrost thaw could release a substantial amount of this carbon as greenhouse gases into the atmosphere through microbial decomposition, potentially dramatically amplifying anthropogenic warming. However, the risk of permafrost thaw is uncertain, with models exhibiting a wide range of possibilities. Assessing the stability of permafrost during past interglacial periods enables evaluation of the sensitivity of permafrost to warming. Cave mineral deposits (speleothems) in areas currently covered with permafrost can act as a proxy for past permafrost thaw, as liquid water is one criteria of speleothem growth and thus implies thawed ground conditions. Previous uranium-thorium (U-Th) dating of speleothems (n=67) from a wide range of latitudes and permafrost zones across the southern Canadian Rockies, Northwest Territories, and the northern Yukon suggest deposition during Marine Isotope Stage (MIS) 11 and 13. The majority of U-Th dates of these speleothems, however, exceed the U-Th dating limit of 600 ka. In this study, we apply uranium-lead (U-Pb) geochronology to several of these speleothems to extend the records of speleothem growth further back in time. Initial results include a U-Pb age of 428 ± 14 ka that replicates a previous U-Th age of 416.8 ± 7.9 ka, and U-Pb ages on two other speleothems of 870 ± 100 ka and 1502 ± 30 ka. The results of currently in progress U-Pb analyses and a comparison of results with paleo-temperature and ice volume reconstructions will also be presented.

  3. Nonlinear electrostatic emittance compensation in kA, fs electron bunches

    Geer, S.B. van der; Loos, M.J. de; Botman, J.I.M.; Luiten, O.J.; Wiel, M.J. van der

    2002-01-01

    Nonlinear space-charge effects play an important role in emittance growth in the production of kA electron bunches with a bunch length much smaller than the bunch diameter. We propose a scheme employing the radial third-order component of an electrostatic acceleration field, to fully compensate the nonlinear space-charge effects. This results in minimal transverse root-mean-square emittance. The principle is demonstrated using our design simulations of a device for the production of high-quality, high-current, subpicosecond electron bunches using electrostatic acceleration in a 1 GV/m field. Simulations using the GPT code produce a bunch of 100 pC and 73 fs full width at half maximum pulse width, resulting in a peak current of about 1.2 kA at an energy of 2 MeV. The compensation scheme reduces the root-mean-square emittance by 34% to 0.4π mm mrad

  4. KA-102 Film/EO Standoff System

    Turpin, Richard T.

    1984-12-01

    The KA-102 is an in-flight selectable film or electro-optic (EU) visible reconnaissance camera with a real-time data link. The lens is a 66-in., f/4 refractor with a 4° field-of-view. The focal plane is a continuous line array of 10,240 COD elements that opera tes in the pushbroom mode. In the film mode, the camera use standard 5-in.-wide 3414 or 3412 film. The E0 imagery is transmitted up to 500 n.mi. to the ground station over a 75-Mbit/sec )(- band data link via a relay aircraft (see Figure 1). The camera may be controlled from the ground station via an uplink or from the cockpit control panel. The 8-ft-diameter ground tracking antenna is located on high ground and linked to the ground station via a 1-mile-long, two-way fiber optic system. In the ground station the imagery is calibrated and displayed in real time on three crt's. Selected imagery may be stored on disk and enhanced, analyzed, and annotated in near-real-time. The imagery may be enhanced and magnified in real time. Hardcopy frames may be made on 8 x 10-in. Polaroid, 35-1m film, or dry silver paper. All the received image and engineering data is recorded on a high-density tape recorder. The aircraft track is recorded on a map plotter. Ground support equipment (GSE), manuals, spares, and training are included in the system. Falcon 20 aircraft were modified on a subcontract to Dynelectron--Ft. Worth.

  5. Computational thermal-fluid dynamics analysis of the laminar flow regime in the meander flow geometry characterizing the heat exchanger used in high temperature superconducting current leads

    Rizzo, Enrico; Heller, Reinhard; Richard, Laura Savoldi; Zanino, Roberto

    2013-01-01

    Highlights: • The laminar regime in the meander flow geometry has been analysed with a previously validated computational strategy. • Several meander flow geometries as well as flow conditions have been analysed. • A range for the Reynolds number has been defined in which the flow can be considered laminar. • Correlations for the pressure drop and the heat transfer coefficients in the laminar regime have been derived. • A comparison between the computed the experimental pressure drop of the W7-X HTS current lead prototype is presented. -- Abstract: The Karlsruhe Institute of Technology and the Politecnico di Torino have developed and validated a computational thermal-fluid dynamics (CtFD) strategy for the systematic analysis of the thermal-hydraulics inside the meander flow heat exchanger used in high-temperature superconducting current leads for fusion applications. In the recent past, the application of this CtFD technique has shown that some operating conditions occurring in these devices may not reach the turbulent regime region. With that motivation, the CtFD analysis of the helium thermal-fluid dynamics inside different meander flow geometries is extended here to the laminar flow regime. Our first aim is to clarify under which operative conditions the flow regime can be considered laminar and how the pressure drop as well as the heat transfer are related to the geometrical parameters and to the flow conditions. From the results of this analysis, correlations for the pressure drop and for the heat transfer coefficient in the meander flow geometry have been derived, which are applicable with good accuracy to the design of meander flow heat exchangers over a broad range of geometrical parameters

  6. Computational thermal-fluid dynamics analysis of the laminar flow regime in the meander flow geometry characterizing the heat exchanger used in high temperature superconducting current leads

    Rizzo, Enrico, E-mail: enrico.rizzo@kit.edu [Institute for Technical Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); Heller, Reinhard [Institute for Technical Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); Richard, Laura Savoldi; Zanino, Roberto [Dipartimento Energia, Politecnico di Torino, 10129 Torino (Italy)

    2013-11-15

    Highlights: • The laminar regime in the meander flow geometry has been analysed with a previously validated computational strategy. • Several meander flow geometries as well as flow conditions have been analysed. • A range for the Reynolds number has been defined in which the flow can be considered laminar. • Correlations for the pressure drop and the heat transfer coefficients in the laminar regime have been derived. • A comparison between the computed the experimental pressure drop of the W7-X HTS current lead prototype is presented. -- Abstract: The Karlsruhe Institute of Technology and the Politecnico di Torino have developed and validated a computational thermal-fluid dynamics (CtFD) strategy for the systematic analysis of the thermal-hydraulics inside the meander flow heat exchanger used in high-temperature superconducting current leads for fusion applications. In the recent past, the application of this CtFD technique has shown that some operating conditions occurring in these devices may not reach the turbulent regime region. With that motivation, the CtFD analysis of the helium thermal-fluid dynamics inside different meander flow geometries is extended here to the laminar flow regime. Our first aim is to clarify under which operative conditions the flow regime can be considered laminar and how the pressure drop as well as the heat transfer are related to the geometrical parameters and to the flow conditions. From the results of this analysis, correlations for the pressure drop and for the heat transfer coefficient in the meander flow geometry have been derived, which are applicable with good accuracy to the design of meander flow heat exchangers over a broad range of geometrical parameters.

  7. Crippled song. Ręka by Bolesław Leśmian within the context of expressionistic poetry

    Katarzyna Szewczyk-Haake

    2009-01-01

    Full Text Available The analysis of Leśmian’s poem Ręka (from the collection of poems entitled Łąka, 1920 leads to distinguishing certain features of the poem that make a connection of the poem with literary expressionism feasible. The above similarities can be testified not only by distinct macabre motifs but also a very peculiar way the narrator constructs his narrative that can be concluded as an attempt at establishing a particular bond between the protagonist and the reader. Works written by the Poznań based expressionists Stanisław Kubicki and Józef Wittlin provide the appropriate context for the poem.

  8. Aeroflot tahab ka ise Moskvast Tallinna lennata / Raimo Poom

    Poom, Raimo

    2011-01-01

    Aeroflot kavatseb suurendada oma rahvusvaheliste reiside hulka umbes veerandi võrra, uute sihtkohtade seas on infoportaali ATO.ru andmeil ka Tallinn. Tallinna lennujaama juhatuse liikme Erik Sakkovi kommentaare

  9. GPM, DPR Level 2A Ka Precipitation V03

    National Aeronautics and Space Administration — The 2AKa algorithm provides precipitation estimates from the Ka radar of the Dual-Frequency Precipitation Radar on the core GPM spacecraft. The product contains two...

  10. NOAA Ship Ka'imimoana Underway Meteorological Data, Quality Controlled

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ka'imimoana Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  11. Under tõi kirjanduse juurde ka Ilvese / Jaanus Kulli

    Kulli, Jaanus, 1955-

    2009-01-01

    Sirje Kiini raamatust "Marie Under : elu, luuletaja identiteet ja teoste vastuvõtt" (Tallinn : Tänapäev, 2009), mille esitlus toimus 10. dets. Kirjanike Majas Tallinnas. Sõnavõtuga esines ka president Toomas Hendrik Ilves

  12. Amobilisasi Sel Bacillus licheniformis KA-08 dalam Menghasilkan Keratinase Termostabil

    Anthoni Agustien

    2012-10-01

    Full Text Available Isolate local Bacillus licheniformis KA-08 known extracellular thermostable keratinase producers. Scale up of thermostable keratinase production can be with cells immobilized. The objective of the research is to thermostable keratinase production of B. licheniformis KA-08 cells immobilization. Thermostable keratinase activities were determined with modification of Brandelli and Riffel method. Protein concentration of enzyme determined with Lowry method. Immobilization of cells by Ca-alginate matrix with Adinarayana method, alginate concentration and amount of alginate bead effects with Beshay method. The result extracellular thermostable keratinase of B. licheniformis KA-08 cells immobilized was maximum produced at 12 times incubation with activity as 9.25 U/mg. Three percent alginate has optimum activity. Three hundred alginate beads has optimum activity. Cells immobilized ofB. licheniformis KA-08 has scale up of thermostable keratinase activity at 2 times than free cells. Thermostable keratinase produced by cell immobilized was nine cycles.

  13. Swedbank hüvitab tekitatud kahju ka fondi vahetajatele

    2009-01-01

    Swedbank hüvitab veel enne 2009. aasta lõppu Private Debt Fondi osaku puhasväärtuse alanemise kolmandas kvartalis ning kompensatsiooni saavad ka need kliendid, kes on andnud sisse pensionifondi vahetamise taotluse

  14. Improvement of Ka-band satellite link availability for real-time IP-based video contribution

    G. Berretta

    2017-09-01

    Full Text Available New High Throughput Satellite (HTS systems allow high throughput IP uplinks/contribution at Ka-band frequencies for relatively lower costs when compared to broadcasting satellite uplinks at Ku band. This technology offers an advantage for live video contribution from remote areas, where the terrestrial infrastructure may not be adequate. On the other hand, the Ka-band is more subject to impairments due to rain or bad weather. This paper addresses the target system specification and provides an optimized approach for the transmission of IP-based video flows through HTS commercial services operating at Ka-band frequencies. In particular, the focus of this study is on the service requirements and the propagation analysis that provide a reference architecture to improve the overall link availability. The approach proposed herein leads to the introduction of a new concept of live service contribution using pairs of small satellite antennas and cheap satellite terminals.

  15. Test of 60 kA coated conductor cable prototypes for fusion magnets

    Uglietti, D.; Bykovsky, N.; Sedlak, K.; Stepanov, B.; Wesche, R.; Bruzzone, P.

    2015-12-01

    Coated conductors could be promising materials for the fabrication of the large magnet systems of future fusion devices. Two prototype conductors (flat cables in steel conduits), each about 2 m long, were manufactured using coated conductor tapes (4 mm wide) from Super Power and SuperOx, with a total tape length of 1.6 km. Each flat cable is assembled from 20 strands, each strand consisting of a stack of 16 tapes surrounded by two half circular copper profiles, twisted and soldered. The tapes were measured at 12 T and 4.2 K and the results of the measurements were used for the assessment of the conductor electromagnetic properties at low temperature and high field. The two conductors were assembled together in a sample that was tested in the European Dipole (EDIPO) facility. The current sharing temperatures of the two conductors were measured at background fields from 8 T up to 12 T and for currents from 30 kA up to 70 kA: the measured values are within a few percent of the values expected from the measurements on tapes (short samples). After electromagnetic cycling, T cs at 12 T and 50 kA decreased from about 12 K to 11 K (about 10%), corresponding to less than 3% of I c.

  16. New tests on the 40 kA Nb3Sn CEA conductor for ITER applications

    Duchateau, J.L.; Bessette, D.; Katheder, H.

    1994-01-01

    New tests have been performed on the 40 kA CEA Nb 3 Sn conductor in the Sultan III facility. The aim of these tests is to obtain key experimental data on the behaviour of Nb 3 Sn conductors for fusion applications under high field and large transport current. The 40 kA Nb 3 Sn CEA conductor has a shape and an internal arrangement of the superconducting wires which is very similar to the ITER conductors. The level of the ac losses experienced by these conductors under varying fields influences deeply their design. The basic experiment consists of producing field pulses on the conductor by means of a coil installed in the bore of the Sultan magnet and recording the integrated voltage obtained on pick-up coils placed on the conductor as a function of time. (author) 4 refs.; 5 figs.; 2 tabs

  17. Thermal contact resistance measurement of conduction cooled binary current lead joint block in cryocooler based self field I-V characterization facility

    Kundu, Ananya, E-mail: ananya@ipr.res.in; Das, Subrat Kumar; Agarwal, Anees Bano Pooja; Pradhan, Subrata [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2016-05-23

    In the present study thermal resistance of conduction cooled current lead joint block employing two different interfacial material namely AlN sheet and Kapton Film have been studied in the temperature range 5K-35K. In each case, the performance of different interlayer materials e.g. Indium foil for moderately pressurized contacts (contact pressure <1 MPa), and Apiezon N Grease, GE varnish for low pressurized contact (contact pressure <1 MPa) is studied. The performances of AlN joint with Indium foil and with Apeizon N Grease are studied and it is observed that the contact resistance reduces more with indium foil as compared to greased contact. The contact resistance measurements of Kapton film with Apiezon N grease and with GE varnish were also carried out in the same temperature range. A comparative study of AlN joint with Indium foil and Kapton with GE varnish as filler material is carried out to demonstrate better candidate material among Kapton and AlN for a particular filler material in the same temperature range.

  18. Considerations on ECFH current drive and bootstrap current for W VII-X

    Gasparino, U.; Maassberg, H.

    1988-01-01

    Low shear is the characteristic of all proposed Wendelstein VII-X configurations. To avoid low harmonic rational numbers within the rotational transform profile, the current contribution to the rotational transform, Δt a α I/B, should be typically less than 10%. This leads to an upper limit of 50 kA (at B = 2.5 T) for the tolerable net toroidal current. A considerable net toroidal current (bootstrap current) is expected by neoclassical theory in the plateau and the low-collisionality regimes. Both radial transport as well as the bootstrap current densities depend sensitively on the magnetic configuration (see A. Montvai, this workshop). In case of an axisymmetric configuration with dimension and plasma parameters as predicted for the high- regime of WVII-X ( ∼ 5%), this current (∼ 0.5/1 MA) would dominate the rotational transform profile. This requires a reduction of magnitude of the bootstrap current to some % of the value of an equivalent tokamak. This reduction must act on the current profile itself and should not be merely obtained by having two channels of currents of different sign at different radii. Due to the possibility of controlling absorbed power and driven current profiles, electron cyclotron waves are a natural candidate for current profile control. Linear calculations show the possibility to drive a counteracting current with a profile similar to the bootstrap one. For ∼ 5% conditions, however, the optimium current drive efficiency (η ∼ 10 kA per MW) is far too low to make ECF-current drive suitable

  19. Round busbar concept for 30 nH, 1.7 kV, 10 kA IGBT non-destructive short-circuit tester

    Smirnova, Liudmila; Pyrhönen, Juha; Iannuzzo, Francesco

    2014-01-01

    Design of a Non-Destructive Test (NDT) set-up for short-circuit tests of 1.7 kV, 1 kA IGBT modules is discussed in this paper. The test set-up allows achieving short-circuit current up to 10 kA. The important objective during the design of the test set-up is to minimize the parasitic inductance...

  20. Status report of the three phase 25 kA, 1.5 kW thermally switched superconducting rectifier, transformer and switches

    ten Kate, Herman H.J.; Holtslag, A.H.M.; Knoben, J.; Steffens, H.A.; van de Klundert, L.J.M.

    1983-01-01

    A 25 kA, 1.5 kW superconducting rectifier system has been developed. This rectifier system working like an a.c.-d.c, converter with a primary current of 35 A at 0.1Hz, will energize a 25 kA coil with an average power of 5.4 MJ/hr and a proposed energy efficiency of at least 96%. Such a highly

  1. A 130 ka reconstruction of rainfall on the Bolivian Altiplano

    Placzek, C. J.; Quade, J.; Patchett, P. J.

    2013-02-01

    New efforts to link climate reconstructions from shoreline deposits and sediment cores yield an improved and more detailed lake history from the Bolivian Altiplano. On the Southern Altiplano, 10 lake oscillations have been identified from this new unified chronology, each coincident with North Atlantic cold events such as Heinrich Events H5, H2, H1, and the Younger Dryas. By coupling this new lake history to a hydrologic budget model we are able to evaluate precipitation variability on the Southern Bolivian Altiplano over the last 130 ka. These modeling efforts underscore the relative aridity of the Altiplano during the rare and small lake cycles occurring between 80 and 20 ka, when colder temperatures combined with little or no change in rainfall produced smaller paleolakes. Relative aridity between 80 and 20 ka contrasts with the immense Tauca lake cycle (18.1-14.1 ka), which was six times larger than modern Lake Titicaca and coincided with Heinrich Event 1. This improved paleolake record from the Southern Altiplano reveals a strong link between central Andean climate and Atlantic sea-surface temperature gradients during the late Pleistocene, even though today rainfall variability is driven mostly by Pacific sea-surface temperature anomalies associated with El Niño/Southern Oscillation. However, not all Heinrich Events appear to result in lake expansions, most conspicuously during the global cold interval between 80 and 20 ka when the Altiplano and Amazon Basin were relatively arid.

  2. Measurements of cross-section of charge current inclusive of antineutrino scattering off nucleons using carbon, iron, lead and scintillator at MINER$\

    Rakotondravohitra, Laza [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-08-18

    Neutrino physics is one of the most active fields in the domaine of high energy physics during the last century. The need of precise measurement of neutrino-nucleus interactions required by the neutrino oscillation experiments is a an exiting step. These measurements of cross-section are more than essential for neutrino oscillation experiment. Over the year, many measurements from varieties of experiments have been presented. MINERνA is one of the world leaders in measuring cross-section of neutrino and antineutrino -nucleus interactions. MINERνA is a neutrino-nucleus scattering experiment installed in the few-GeV NuMI beam line at Fermilab. In order to study nuclear dependence, MINERνA is endowed with different types of solid nuclear targets as well are liquid targets such as helium and water. This thesis presents measurements of cross-section of antineutrino scattering off nucleons using a variety of solid nuclear targets, carbon, iron, lead and also polystyrene scintillator (CH). The data set of antineutrino used for this analysis was taken between March and July 2010 with a total of 1.60X1020 protons on target. Charged current inclusive interactions were selected by requiring a positive muon and kinematics limitation of acceptance of the muon spectrometer are applied. The analysis requires neutrino energy between 2GeV et 20GeV and the angle of muon θmu < 17degree . The absolute cross-section # as function of neutrino energy and the differential cross-section dσ/ dxbj measured and shown the corresponding systematics for each nuclear targets. Data results are compared with prediction of the models implemented in the neutrino events generators GENIE 2.6.2 used by the experiment.

  3. Stairs to Skałka. From Iconography of Martyrdom of Bishop Stanislaus

    Tomasz Węcławowicz

    2003-12-01

    flights of stairs or ladders leading to the gates from the site where the hired assassins mutilate the body of the Saint. Moreover, nearly in every depiction figures can be seen mounting the stairs towards the open gates. These figures as well as stairs or ladders or gates are not to be found in the texts of The Life o f the Saint because painted and graphic renderings have primarily moralizing aim. The archetype of ‘the stairs to Heaven’ is substantiated in the iconography of the Martyrdom as stairs to the church on Skałka. The interpretation of the stairs to Skałka can therefore be resented as follows: L i t e r a l l y , stairs to the gates are indeed stairs leading to the church ‘Na Skałce’. I n a n a l l e g o r i c a l interpretation, they are the Cross of Christ, who enabled the faithful to ascend to Redemption. A typological unity of steps on Jacob’s ladder and the Cross of Christ has frequently been raised in exegesis, and St. Stanislaus appears here, like every martyr, as alter Christus. In a t r o p o l o g i c a l interpretation, ascending stairs indicate aspiring towards perfection through mounting the steps of deeds. I n a n a n a g o g i c interpretation, these stairs lead to the gates of heavenly Jerusalem.

  4. Development of Fruška Gora and some open questions of sustainability

    Bajić-Brković Milica

    2010-01-01

    Full Text Available Future development of Fruška Gora triggers numerous questions from the domain of sustainability. The solutions defined in the spatial plan-PPPPN Fruška Gora 2022, can be carried out only on condition that the current course of spatial planning and space related decision making change, so that the respective procedures become more sensitive to the specific requirements of sustainability. Sustainability by itself affects the way planning is being performed, while the specifics of a concrete case, like the case explored in this paper, set up a particular input relevant for both the conceptual and methodological aspects of planning. The proposals of implementing the specific sustainability-based techniques along with the practical implications of their use throughout the planning process are examined in this paper. Normally, most of them are not part of a standard planning procedure, however, they become highly relevant in cases like Fruška Gora, or similar. A sequence of innovations and possible modifications of/within the existing paradigm proposed here include: the prevention techniques, carrying capacity assessment as it relates to the eco-balance, risk assessment, impact analysis, eco-sensitive zoning, GIS based monitoring, etc. Special attention is given to the issues of physical and environmental quality, as they relate to sustainability.

  5. LEADING WITH LEADING INDICATORS

    PREVETTE, S.S.

    2005-01-01

    This paper documents Fluor Hanford's use of Leading Indicators, management leadership, and statistical methodology in order to improve safe performance of work. By applying these methods, Fluor Hanford achieved a significant reduction in injury rates in 2003 and 2004, and the improvement continues today. The integration of data, leadership, and teamwork pays off with improved safety performance and credibility with the customer. The use of Statistical Process Control, Pareto Charts, and Systems Thinking and their effect on management decisions and employee involvement are discussed. Included are practical examples of choosing leading indicators. A statistically based color coded dashboard presentation system methodology is provided. These tools, management theories and methods, coupled with involved leadership and employee efforts, directly led to significant improvements in worker safety and health, and environmental protection and restoration at one of the nation's largest nuclear cleanup sites

  6. Predicting pKa for proteins using COSMO-RS

    Andersson, Martin Peter; Jensen, Jan Halborg; Stipp, Susan Louise Svane

    2013-01-01

    We have used the COSMO-RS implicit solvation method to calculate the equilibrium constants, pKa, for deprotonation of the acidic residues of the ovomucoid inhibitor protein, OMTKY3. The root mean square error for comparison with experimental data is only 0.5 pH units and the maximum error 0.8 p......H units. The results show that the accuracy of pKa prediction using COSMO-RS is as good for large biomolecules as it is for smaller inorganic and organic acids and that the method compares very well to previous pKa predictions of the OMTKY3 protein using Quantum Mechanics/Molecular Mechanics. Our approach...

  7. The Determination of "Apparent" pKa's. Part II: An Experiment Using Very Weak Acids (pKa's > 11.4).

    Cawley, John J.

    1995-01-01

    Presents an experiment designed to show students that the Henderson-Hasselbalch equation will fail when they use this particular one-half titration technique for acids with large pKa's. Involves determining the apparent pKa for such acids and using that to calculate the true pKa. (JRH)

  8. Quench propagation in the superconducting 6 kA flexible busbars of the LHC

    Herzog, R.; Calvi, M.; Sonnemann, F.; Pelegrin-Carcelen, J.M.

    2002-01-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit components

  9. Quench Propagation in the Superconducting 6 kA Flexible Busbars of the LHC

    Calvi, M; Pelegrin-Carcelen, J M; Sonnemann, F

    2002-01-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit c...

  10. Quench propagation in the superconducting 6 kA flexible busbars of the LHC

    Herzog, R.; Calvi, M.; Sonnemann, F.; Pelegrin-Carcelen, J. M.

    2002-05-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit components.

  11. The effects of multiple features of alternatively spliced exons on the KA/KS ratio test

    Chen Feng-Chi

    2006-05-01

    Full Text Available Abstract Background The evolution of alternatively spliced exons (ASEs is of primary interest because these exons are suggested to be a major source of functional diversity of proteins. Many exon features have been suggested to affect the evolution of ASEs. However, previous studies have relied on the KA/KS ratio test without taking into consideration information sufficiency (i.e., exon length > 75 bp, cross-species divergence > 5% of the studied exons, leading to potentially biased interpretations. Furthermore, which exon feature dominates the results of the KA/KS ratio test and whether multiple exon features have additive effects have remained unexplored. Results In this study, we collect two different datasets for analysis – the ASE dataset (which includes lineage-specific ASEs and conserved ASEs and the ACE dataset (which includes only conserved ASEs. We first show that information sufficiency can significantly affect the interpretation of relationship between exons features and the KA/KS ratio test results. After discarding exons with insufficient information, we use a Boolean method to analyze the relationship between test results and four exon features (namely length, protein domain overlapping, inclusion level, and exonic splicing enhancer (ESE frequency for the ASE dataset. We demonstrate that length and protein domain overlapping are dominant factors, and they have similar impacts on test results of ASEs. In addition, despite the weak impacts of inclusion level and ESE motif frequency when considered individually, combination of these two factors still have minor additive effects on test results. However, the ACE dataset shows a slightly different result in that inclusion level has a marginally significant effect on test results. Lineage-specific ASEs may have contributed to the difference. Overall, in both ASEs and ACEs, protein domain overlapping is the most dominant exon feature while ESE frequency is the weakest one in affecting

  12. Multi-Step Ka/Ka Dichroic Plate with Rounded Corners for NASA's 34m Beam Waveguide Antenna

    Veruttipong, Watt; Khayatian, Behrouz; Hoppe, Daniel; Long, Ezra

    2013-01-01

    A multi-step Ka/Ka dichroic plate Frequency Selective Surface (FSS structure) is designed, manufactured and tested for use in NASA's Deep Space Network (DSN) 34m Beam Waveguide (BWG) antennas. The proposed design allows ease of manufacturing and ability to handle the increased transmit power (reflected off the FSS) of the DSN BWG antennas from 20kW to 100 kW. The dichroic is designed using HFSS and results agree well with measured data considering the manufacturing tolerances that could be achieved on the dichroic.

  13. Response of benthic foraminifera to 4.2 ka cooling event in the Nakdong River delta, southeast Korea

    Takata, H.; Khim, B. K.; Cheong, D.; Shin, S.

    2016-02-01

    Here we report the change of benthic foraminifera in response to 4.2 ka cooling event in the Nakdong River delta (southeastern Korea). It has been known that this cooling event caused climatic deteriorations in the world, which is closely related to the decline/development of the civilizations (e.g., Kawahata et al., 2009). This event was also correlated to one of Bond Events in the North Atlantic. Because coastal sediment depositions have been influenced by both oceanographic and terrestrial climatic changes, the study may provide us clue to understand the possible teleconnection of the cooling event between the North Atlantic and the East Asian margin. We investigated fossil benthic foraminiferal faunas and planktonic/total foraminiferal ratio (P/T ratio) at two borehole cores, ND-01 and ND-02 (landward and seaward sites, respectively). Common constituents are taxa from bay to shelf environments in the East Asian margin. Biotic response of benthic foraminifera partly changed after 4.2 ka showing that Haynesina sp. A (opportunistic species?) decreased significantly at core ND-01. In addition, P/T ratio at both core sites showed temporal decline at 4.2 ka. This suggests the decreasing influence of the seawater relative to the coastal water. Holocene fluctuations of the Tsushima Warm Current, a branch of Kuroshio, flowing off the Nakdong River delta, have been documented. The decline pattern of P/T ratio in this area is similar to that of total sulfur content in Lake Tougou-ike, southwestern Japan at 4 ka which was interpreted as the influence of the small sea-level falling (Kato et al., 2003). According to the similar stratigraphic variation patterns between our and their studies, our finding suggests that this event was not regional but related to the fluctuations of the Tsushima Warm Current. Thus, biotic response of benthic foraminifera in the Nakdong River delta recorded 4.2 ka cooling event related to temporal weakening of the Tsushima Warm Current.

  14. Che legend elab ka 40 aastat hiljem / Evelyn Kaldoja

    Kaldoja, Evelyn, 1980-

    2007-01-01

    Ilmunud ka: Postimees : na russkom jazõke 9. okt. lk. 10. Argentinas sündinud ja 1967. aastal hukatud revolutsionääri Ernesto Che Guevara poliitikukarjäärist, tema panusest Kuuba revolutsiooni ja poliitikasse. Ernesto Che Guevara mälestamisest Ladina-Ameeerika riikides. Lisa: Kuuba revolutsioon; Che Guevara elu

  15. Euroopa Liit lubab toetada Afganistani ka tulevikus heldelt / Ahto Lobjakas

    Lobjakas, Ahto, 1970-

    2005-01-01

    Euroopa Komisjoni president Jose Manuel Barroso ja Euroopa Liidu ühise välispoliitika peakoordinaator Javier Solana lubasid Afganistani presidendile Hamid Karzaile, et Euroopa Liit jätkab kestva välisabi osutamist riigile ka peale parlamendivalimiste toimumist septembris

  16. Additive manufacturing of Ka-band antennas for wireless communications

    Armendariz, Unai; Rommel, Simon; Rodríguez Páez, Juan Sebastián

    2016-01-01

    This paper presents the design and fabrication of WR-28 waveguide horn antennas operating in the Ka-band frequency range between 26.5 GHz and 40 GHz through 3D printing. Three different antennas are fabricated from polylactide acid filaments in conductive and non-conductive variants; the latter i...

  17. Ehitusala tõus jätkus ka mullu

    2004-01-01

    Ilmunud ka: Delovõje Vedomosti, 3. nov. 2004, lk. 14-15. Ehitusfirmade TOP 95 aastal 2003. Kasumi TOP 40. Käibe TOP 40. TOP-i koostamise metoodika. Kasumi kasvu TOP 20. Käibe kasvu TOP 20. Omakapitali tootluse TOP 20. Rentaabluse TOP 20. Ehitusettevõtete üld- ja finantsandmed

  18. Kas läheb ka Ruudi tapmiseks? / Kati Murutar

    Murutar, Kati, 1967-

    2006-01-01

    Lastefilm "Ruudi" : stsenaristid Katrin Laur, Aare Toikka, Aarne Mägi : režissöör Katrin Laur : nimiosas lapsnäitleja Paul Oskar Soe : Allfilm - MRP Matila Röhr Productions - Schmidtz Katze Filmkollektiv 2006. Võetud kõne alla ka Peeter Simmi "Kõrini!" ja Peeter Urbla "Stiilipeo" arvustaja meelest teenimatult mahategevad retsensioonid

  19. Tõnu Talve "Ka" tuuritab Kadrinas ja Rakveres / Ants Juske

    Juske, Ants, 1956-2016

    2005-01-01

    Tõnu Talve maalidest. Kadrinas esitatud trio Fragile performance'st ja näitusest tsüklist "Ka" Rakveres. Rakvere näitusel Teele Tuuna ja kolmeaastase tütre Anneliise tööd. Trio Fragile koosseisus on kitarrist Robert Jürjendal, trummar Arvo Urb ja maalija Tõnu Talve

  20. Ka-Band Klystron Amplifier for CUBESATs, Phase I

    National Aeronautics and Space Administration — We propose a Ka-Band klystron amplifier for use in CubeSats. It will operate at 35.7 GHz, have 400 MHz of bandwidth, and output at least 32 watts of saturated power....

  1. "7 vaprat" ei lõpeta ka suvel / H. S.

    H. S.

    2002-01-01

    Populaarne muusikaedetabelisaade "7 vaprat" läheb juunis ansamblitega Terminaator, Tuberkuloited, No Big Silence, Blacky, Speed Free ja Hell Can Wait suvetuurile. 11. juunil antakse kontsert Tartus, 12. juunil Rakveres, 13. juunil Pärnus ja 15. juunil Tallinnas. Kontsertidest valmivad ka telesaated, saatejuht Villu Tamme

  2. Überlegungen zu der sumerischen Zeichen-Gruppe ŠÈ.KA

    Such-Gutiérrez, Marcos

    2003-12-01

    Full Text Available This paper deals with the different readings and meanings of the signs ŠÈ.KA. One of these readings is Zì.KA or zì-KA/ka, which has been traditionally interpreted as a kind of flour or as the process of milling. However, a revision of the texts from the Third Dynasty of Ur (c. 2117-2008 B.C., in which the group of signs ZÌ.KA o zì-KA/ka appears, shows that this term is actually a kind of gift.

    El presente artículo trata de las diferentes lecturas y significados del grupo de signos ŠÈ.KA. Entre dichas lecturas se encuentra la de ZÌ.KA o zì-KA/ka, que ha sido tradicionalmente interpretada bien como un tipo de harina, o bien como la acción que conduce a su fabricación. Sin embargo, una revisión de los textos de la III Dinastía de Ur (c. 2117-2008 a.C. en los que aparece el término ZÌ.KA o zì-KA/ka demuestra que, en realidad, con él se hace referencia a un tipo de regalo.

  3. Experimental and analytical investigation on metal damage suffered from simulated lightning currents

    Yakun, LIU; Zhengcai, FU; Quanzhen, LIU; Baoquan, LIU; Anirban, GUHA

    2017-12-01

    The damage of two typical metal materials, Al alloy 3003 and steel alloy Q235B, subjected to four representative lightning current components are investigated by laboratory and analytical studies to provide fundamental data for lightning protection. The four lightning components simulating the natural lightning consist of the first return stroke, the continuing current of interval stroke, the long continuing current, and the subsequent stroke, with amplitudes 200 kA, 8 kA, 400 A, and 100 kA, respectively. The damage depth and area suffered from different lightning components are measured by the ultrasonic scanning system. And the temperature rise is measured by the thermal imaging camera. The results show that, for both Al 3003 and steel Q235B, the first return stroke component results in the largest damage area with damage depth 0.02 mm uttermost. The long continuing current component leads to the deepest damage depth of 3.3 mm for Al 3003 and much higher temperature rise than other components. The correlation analysis between damage results and lightning parameters indicates that the damage depth has a positive correlation with charge transfer. The damage area is mainly determined by the current amplitude and the temperature rise increases linearly with the charge transfer larger.

  4. Plasma current profile during current reversal in a tokamak

    Huang Jianguo; Yang Xuanzong; Zheng Shaobai; Feng Chunhua; Zhang Houxian; Wang Long

    1999-01-01

    Alternating current operation with one full cycle and a current level of 2.5 kA have been achieved in the CT-6B tokamak. The poloidal magnetic field in the plasma is measured with two internal magnetic probes in repeated discharges. The current distribution is reconstructed with an inversion algorithm. The inverse current first appears on the weak field side. The existence of magnetic surfaces and rotational transform provide particle confinement in the current reversal phase

  5. Mars Global Surveyor Ka-Band Frequency Data Analysis

    Morabito, D.; Butman, S.; Shambayati, S.

    2000-01-01

    The Mars Global Surveyor (MGS) spacecraft, launched on November 7, 1996, carries an experimental space-to-ground telecommunications link at Ka-band (32 GHz) along with the primary X-band (8.4 GHz) downlink. The signals are simultaneously transmitted from a 1.5-in diameter parabolic high gain antenna (HGA) on MGS and received by a beam-waveguide (BWG) R&D 34-meter antenna located in NASA's Goldstone Deep Space Network (DSN) complex near Barstow, California. The projected 5-dB link advantage of Ka-band relative to X-band was confirmed in previous reports using measurements of MGS signal strength data acquired during the first two years of the link experiment from December 1996 to December 1998. Analysis of X-band and Ka-band frequency data and difference frequency (fx-fka)/3.8 data will be presented here. On board the spacecraft, a low-power sample of the X-band downlink from the transponder is upconverted to 32 GHz, the Ka-band frequency, amplified to I-W using a Solid State Power Amplifier, and radiated from the dual X/Ka HGA. The X-band signal is amplified by one of two 25 W TWTAs. An upconverter first downconverts the 8.42 GHz X-band signal to 8 GHz and then multiplies using a X4 multiplier producing the 32 GHz Ka-band frequency. The frequency source selection is performed by an RF switch which can be commanded to select a VCO (Voltage Controlled Oscillator) or USO (Ultra-Stable Oscillator) reference. The Ka-band frequency can be either coherent with the X-band downlink reference or a hybrid combination of the USO and VCO derived frequencies. The data in this study were chosen such that the Ka-band signal is purely coherent with the X-band signal, that is the downconverter is driven by the same frequency source as the X-band downlink). The ground station used to acquire the data is DSS-13, a 34-meter BWG antenna which incorporates a series of mirrors inside beam waveguide tubes which guide the energy to a subterranean pedestal room, providing a stable environment

  6. High power semiconductor switches in the 12 kV, 50 kA pulse generator of the SPS beam dump kicker system

    Bonthond, J; Faure, P; Vossenberg, Eugène B

    2001-01-01

    Horizontal deflection of the beam in the dump kicker system of the CERN SPS accelerator is obtained with a series of fast pulsed magnets. The high current pulses of 50 kA per magnet are generated with capacitor discharge type generators which, combined with a resistive free-wheel diode circuit, deliver a critically damped half-sine current with a rise-time of 25 ms. Each generator consists of two 25 kA units, connected in parallel to a magnet via a low inductance transmission line.

  7. Kui suudab Steve, suudab ka Apple / Tarvo Vaarmets

    Vaarmets, Tarvo

    2008-01-01

    Ehkki Apple'i kolmanda kvartali kasum kasvas kolmandiku võrra ja oli oodatust kümnendiku jagu suurem, langes ettevõtte aktsia hind börsil. Investoreid teeb rahutuks nii ettevõtte juhi Steve Jobsi tervis kui ka Apple'i majandusprognoos neljandaks kvartaliks. Lisa: Analüütikud on aktsia suhtes üksmeelel. Diagramm: Aktsia hinnal taas suund alla

  8. Riigikogus tehakse ka tööd / Vilja Savisaar

    Savisaar, Vilja, 1962-

    2007-01-01

    Ilmunud ka: Sakala, 13. juuni 2007, lk. 2; Lääne Elu, 14. juuni 2007, lk. 2; Põhjarannik, 14. juuni 2007, lk. 2; Severnoje Poberezhje, 14. juuni 2007, lk. 2; Vooremaa, 14. juuni 2007, lk. 2; Harju Ekspress, 15. juuni 2007, lk. 8; Järva Teataja, 16. juuni 2007, lk. 2; Koit, 21. juuni 2007, lk. 6. Parlamendiliige Keskerakonna fraktsiooni poolt parlamendis algatatud eelnõudest

  9. Eestil on Euroopas ka oma tee / Jürgen Ligi

    Ligi, Jürgen, 1959-

    2004-01-01

    Ilmunud ka: Põhjarannik, 17. apr. 2004, lk. 2; Severnoje Poberezhje, 17. apr. 2004, lk. 2; Koit,17. apr. 2004, lk. 6; Meie Maa, 17. apr. 2004, lk. 2; Hiiu Leht, 20. apr. 2004, lk. 2; Virumaa Nädalaleht, 23. apr. 2004, lk. 2; Sakala, 23. apr. 2004, lk. 2; Valgamaalane, 8. mai 2004, lk. 2. Maksu- ja sotsiaalpoliitika otsustusõigusest ning kaitsmisest EL-i riikides

  10. Production LHC HTS power lead test results

    Tartaglia, M; Fehér, S; Huang, Y; Orris, D F; Pischalnikov, Y; Rabehl, Roger Jon; Sylvester, C D; Zbasnik, J

    2005-01-01

    The Fermilab Magnet test facility has built and operated a test stand to characterize the performance of HTS power leads. We report here the results of production tests of 20 pairs of 7.5 kA HTS power leads manufactured by industry for installation in feed boxes for the LHC Interaction Region quadrupole strings. Included are discussions of the thermal, electrical, and quench characteristics under "standard" and "extreme" operating conditions, and the stability of performance across thermal cycles.

  11. Production LHC HTS power lead test results

    Tartaglia, M.A.; Carcagno, R.H.; Feher, S.; Huang, Y.; Orris, D.F.; Pischalnikov, Y.; Rabehl, R.J.; Sylvester, C.; Zbasnik, J.

    2004-01-01

    The Fermilab Magnet test facility has built and operated a test stand to characterize the performance of HTS power leads. We report here the results of production tests of 20 pairs of 7.5 kA HTS power leads manufactured by industry for installation in feed boxes for the LHC Interaction Region quadrupole strings. Included are discussions of the thermal, electrical, and quench characteristics under ''standard'' and ''extreme'' operating conditions, and the stability of performance across thermal cycles

  12. Reverberation Mapping of the Kepler target KA1858+48

    Pei, Liuyi; Barth, A. J.; Malkan, M. A.; Cenko, S. B.; Clubb, K. I.; Filippenko, A. V.; Gates, E. L.; Horst, J.; Joner, M. D.; Leonard, D. C.; Sand, D. J.

    2013-01-01

    KA1858+48 is a Seyfert 1 galaxy at redshift 0.078 and is among the brightest active galaxies being monitored by the Kepler mission. We have carried out a reverberation mapping program designed to measure the broad-line region size and estimate the mass of the black hole in KA1858+48. We obtained spectroscopic data using the Kast Spectrograph at the Lick 3 m telescope during dark runs from late winter through fall of 2012, by requesting an observation on each night that the Kast Spectrograph was mounted on the telescope. We also obtained V-band images from the Nickel 1 m telescope at Lick Observatory, the 0.9 m telescope at Brigham Young University West Mountain Observatory, the Faulkes Telescope North at the Las Cumbres Observatory Global Telescope, the KAIT telescope at Lick Observatory, and the 1 m telescope at Mt. Laguna Observatory. The H-beta light curve shows a lag time of approximately 12 days with respect to the V-band continuum flux variations. We will present the continuum and emission-line light curves, cross-correlation lag measurements, and a preliminary estimate of the black hole mass in KA1858+48.

  13. X/Ka Celestial Frame Improvements: Vision to Reality

    Jacobs, C. S.; Bagri, D. S.; Britcliffe, M. J.; Clark, J. E.; Franco, M. M.; Garcia-Miro, C.; Goodhart, C. E.; Horiuchi, S.; Lowe, S. T.; Moll, V. E.; hide

    2010-01-01

    In order to extend the International Celestial Reference Frame from its S/X-band (2.3/8.4 GHz) basis to a complementary frame at X/Ka-band (8.4/32 GHz), we began in mid-2005 an ongoing series of X/Ka observations using NASA s Deep Space Network (DSN) radio telescopes. Over the course of 47 sessions, we have detected 351 extra-galactic radio sources covering the full 24 hours of right ascension and declinations down to -45 degrees. Angular source position accuracy is at the part-per-billion level. We developed an error budget which shows that the main errors arise from limited sensitivity, mismodeling of the troposphere, uncalibrated instrumental effects, and the lack of a southern baseline. Recent work has improved sensitivity by improving pointing calibrations and by increasing the data rate four-fold. Troposphere calibration has been demonstrated at the mm-level. Construction of instrumental phase calibrators and new digital baseband filtering electronics began in recent months. We will discuss the expected effect of these improvements on the X/Ka frame.

  14. Lead poisoning

    ... drinking water in homes containing pipes that were connected with lead solder . Although new building codes require ... lead in their bodies when they put lead objects in their mouths, especially if they swallow those ...

  15. Lead Poisoning

    Lead is a metal that occurs naturally in the earth's crust. Lead can be found in all parts of our ... from human activities such as mining and manufacturing. Lead used to be in paint; older houses may ...

  16. Concentrating Solar Power Projects - KaXu Solar One | Concentrating Solar

    Power | NREL KaXu Solar One This page provides information on KaXu Solar One, a concentrating solar power (CSP) project, with data organized by background, parcipants and power plant configuration . Status Date: April 14, 2015 Project Overview Project Name: KaXu Solar One Country: South Africa Location

  17. Current studies on bacterospermia the leading cause of male infertility: A protégé and potential threat towards mans extinction

    Ibeh Nnana Isaiah; Bikwe Thomas Nche; Ibeh Georgina Nwagu; Ibeh Isaiah Nnanna

    2011-01-01

    Background: The current rise of male infertility associated with bacterospermia and urogenital infection has been on the increase amongst adult married males in Benin metropolis and a major cause of concern to male fertility and reproduction in Nigeria. Aim: To microbiologically isolate and study the infectious agent that has led to male infertility and also to study the percentage occurrence of bacteropsermia and urogenital caused infertility in adult married males in Benin metropolis Materi...

  18. The Alleret Maar lacustrine sequence (French Massif Central): a 150 ka long early-middle Pleistocene continental paleoenvironmental record.

    Nomade, S.; Pastre, J.; Guillou, H.; Gauthier, A.; Scaillet, S.

    2008-12-01

    Lacustrine maar sequences of the French Massif Central are of great interest for paleoclimatic and paleoenvironmental reconstructions of mid-latitudes Quaternary continental environments. In particular, the western Velay region yields exceptional sequences spanning the last 450 ka (Reille et al., J. Quat. Sci. 2000). However, older sequences remain largely unknown despite the presence of interbedded alkaline tephras allowing precise absolute radiochronological control of many lacustrine squences. The Alleret maar is a 1500 m wide phreatomagmatic crater that provides a long lacustrine sequence (41 m). The upper part of this sequence (AL2 core, 14.6 m) was studied between 2005 and 2006 (Pastre et al., C. R. Acad Sci, 2007). A 39Ar/40Ar date (557 ± 5ka) obtained from an interbedded tephra layer located at 7m as well as the associated pollen data attribute the beginning of this sequence to the MIS 15. Thanks to the AL3 core recovered in 2005 (40.6 m, CNRS Meudon) several new tephra layers were discovered in the bottom part of this lacustrine sequence. Three new 39Ar/40Ar ages (single crystal analyses) from trachytic tephra layers were obtained at the LSCE Argon Laboratory (France). These layers are located at -30.2, -36.2 and -39.2m. Ages obtained relative to the ACR-2 flux standard (1,201Ma, Kuiper et al., Science, 2008) range from 692 ± 6 ka (MSWD: 2.3, n=18) for the youngest (-30.2m) to 726 ± 9Ka Ka (MSWD: 2.2, n=12) for the lowest tephra located at -39.2m. These new dates indicate a relatively homogeneous deposition rate of 3.5cm/ka and that the last 10 meters cover the MIS 17-MIS18 period. According to these current radiochronological data the complete lacustrine sequence last more than 150ka. Ongoing sedimentary and pollen studies will allow to extend the paleoenvironmental and paleoclimatic records of the French Massif Central towards the beginning of the early middle Pleistocene.

  19. Theoretical prediction of pKa in methanol: testing SM8 and SMD models for carboxylic acids, phenols, and amines.

    Miguel, Elizabeth L M; Silva, Poliana L; Pliego, Josefredo R

    2014-05-29

    Methanol is a widely used solvent for chemical reactions and has solvation properties similar to those of water. However, the performance of continuum solvation models in this solvent has not been tested yet. In this report, we have investigated the performance of the SM8 and SMD models for pKa prediction of 26 carboxylic acids, 24 phenols, and 23 amines in methanol. The gas phase contribution was included at the X3LYP/TZVPP+diff//X3LYP/DZV+P(d) level. Using the proton exchange reaction with acetic acid, phenol, and ammonia as reference species leads to RMS error in the range of 1.4 to 3.6 pKa units. This finding suggests that the performance of the continuum models for methanol is similar to that found for aqueous solvent. Application of simple empirical correction through a linear equation leads to accurate pKa prediction, with uncertainty less than 0.8 units with the SM8 method. Testing with the less expensive PBE1PBE/6-311+G** method results in a slight improvement in the results.

  20. Elevation Change Derived from SARAL/ALtiKa Altimetric Mission: Quality Assessment and Performance of the Ka-Band

    Quanming Yang

    2018-04-01

    Full Text Available The waveform retracking algorithm is a key factor that affects the accuracy of elevation change from satellite altimetry over an ice sheet. The elevation change results from four waveform retracker algorithms (ICE1/ICE2/Sea Ice/OCEAN provided by the Satellite with ARgos and ALtiKa (SARAL/ALtiKa data were compared using repeated SARAL data between March 2013 and April 2016 to determine the optimal retracker in the crossovers of descending and ascending orbits over a Greenland ice sheet (GrIS. The ICE1 provided slightly better results than the three other algorithms with the lowest standard deviation (SD of 0.30 m year−1. Further comparison was also conducted between the Satellite with ARgos and ALtiKa (SARAL and Operation ICEBridge laser data, thereby indicating that ICE1 was the best retracker with an Root Mean Square Error (RMSE of 0.43 m year−1. The distribution of elevation change rate and uncertainties over Greenland from SARAL were presented using the selected ICE1 retracker with a volume loss of 40 ± 12 km3 year−1. This volume loss did not include the fast-changing coastal areas of the GrIS. A large thinning was observed in Jakobshavn Isbræ, and a trend that extended far inland was also found from 2013–2016. Furthermore, a melting ice sheet was observed in the large areas northwest over the GrIS.

  1. Origin of the pKa shift of the catalytic lysine in acetoacetate decarboxylase.

    Ishikita, Hiroshi

    2010-01-01

    The pKa value of Lys115, the catalytic residue in acetoacetate decarboxylate, was calculated using atomic coordinates of the X-ray crystal structure with consideration of the protonation states of all titratable sites in the protein. The calculated pKa value of Lys115 (pKa(Lys115)) was unusually low (approximately 6) in agreement with the experimentally measured value. Although charged residues impact pKa(Lys115) considerably in the native protein, the significant pKa(Lys115) downshift in the...

  2. Leakage current behavior in lead-free ferroelectric (K,Na)NbO3-LiTaO3-LiSbO3 thin films

    Abazari, M.; Safari, A.

    2010-12-01

    Conduction mechanisms in epitaxial (001)-oriented pure and 1 mol % Mn-doped (K0.44,Na0.52,Li0.04)(Nb0.84,Ta0.1,Sb0.06)O3 (KNN-LT-LS) thin films on SrTiO3 substrate were investigated. Temperature dependence of leakage current density was measured as a function of applied electric field in the range of 200-380 K. It was shown that the different transport mechanisms dominate in pure and Mn-doped thin films. In pure (KNN-LT-LS) thin films, Poole-Frenkel emission was found to be responsible for the leakage, while Schottky emission was the dominant mechanism in Mn-doped thin films at higher electric fields. This is a remarkable yet clear indication of effect of 1 mol % Mn on the resistive behavior of such thin films.

  3. Thermal Deformation and RF Performance Analyses for the SWOT Large Deployable Ka-Band Reflectarray

    Fang, H.; Sunada, E.; Chaubell, J.; Esteban-Fernandez, D.; Thomson, M.; Nicaise, F.

    2010-01-01

    A large deployable antenna technology for the NASA Surface Water and Ocean Topography (SWOT) Mission is currently being developed by JPL in response to NRC Earth Science Tier 2 Decadal Survey recommendations. This technology is required to enable the SWOT mission due to the fact that no currently available antenna is capable of meeting SWOT's demanding Ka-Band remote sensing requirements. One of the key aspects of this antenna development is to minimize the effect of the on-orbit thermal distortion to the antenna RF performance. An analysis process which includes: 1) the on-orbit thermal analysis to obtain the temperature distribution; 2) structural deformation analysis to get the geometry of the antenna surface; and 3) the RF performance with the given deformed antenna surface has been developed to accommodate the development of this antenna technology. The detailed analysis process and some analysis results will be presented and discussed by this paper.

  4. An experimental mechanical switch for 3 kA driven by superconducting coils

    Herman, H.J.; Ten Haken, B.; Van de Klundert, L.J.M.

    1986-01-01

    Usually mechanical switches that are built for use in superconducting circuits are driven in some way by a rod which is controlled at room temperature. In this paper, an alternative method to drive the electrodes of the switch is reported. In fact the new device is a superconducting relay that uses an antiseries connection of two superconducting air-core coils. The repulsing force of these relay coils enables the switch to be closed by applying a pressure to the electrodes. The off-state is effected by a set of springs which interrupt the electrodes when the coil current is switched off. We realized that this electro-magnetic method of producing large forces could be promising for driving a mechanical switch. The desired method was demonstrated by an experimental model. A switch-on resistance of 8*10 -8 Ω with a switch current of 3 kA and a contact force of 20 kN was measured

  5. Pollen-based continental climate reconstructions at 6 and 21 ka: a global synthesis

    Bartlein, P.J. [University of Oregon, Department of Geography, Eugene, Oregon (United States); Harrison, S.P. [University of Bristol, School of Geographical Sciences, Bristol (United Kingdom); Macquarie University, School of Biological Sciences, North Ryde, NSW (Australia); Brewer, S. [University of Wyoming, Botany Department, Wyoming (United States); Connor, S. [University of the Algarve, Centre for Marine and Environmental Research, Faro (Portugal); Davis, B.A.S. [Ecole Polytechnique Federale de Lausanne, School of Architecture, Civil and Environmental Engineering, Lausanne (Switzerland); Gajewski, K.; Viau, A.E. [University of Ottawa, Department of Geography, Ottawa, ON (Canada); Guiot, J. [CEREGE, Aix-en-Provence cedex 4 (France); Harrison-Prentice, T.I. [GTZ, PAKLIM, Jakarta (Indonesia); Henderson, A. [University of Minnesota, Department of Geology and Geophysics, Minneapolis, MN (United States); Peyron, O. [Laboratoire Chrono-Environnement UMR 6249 CNRS-UFC UFR Sciences et Techniques, Besancon Cedex (France); Prentice, I.C. [Macquarie University, School of Biological Sciences, North Ryde, NSW (Australia); University of Bristol, QUEST, Department of Earth Sciences, Bristol (United Kingdom); Scholze, M. [University of Bristol, QUEST, Department of Earth Sciences, Bristol (United Kingdom); Seppae, H. [University of Helsinki, Department of Geology, P.O. Box 65, Helsinki (Finland); Shuman, B. [University of Wyoming, Department of Geology and Geophysics, Laramie, WY (United States); Sugita, S. [Tallinn University, Institute of Ecology, Tallinn (Estonia); Thompson, R.S. [US Geological Survey, PO Box 25046, Denver, CO (United States); Williams, J. [University of Wisconsin, Department of Geography, Madison, WI (United States); Wu, H. [Chinese Academy of Sciences, Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Beijing (China)

    2011-08-15

    Subfossil pollen and plant macrofossil data derived from {sup 14}C-dated sediment profiles can provide quantitative information on glacial and interglacial climates. The data allow climate variables related to growing-season warmth, winter cold, and plant-available moisture to be reconstructed. Continental-scale reconstructions have been made for the mid-Holocene (MH, around 6 ka) and Last Glacial Maximum (LGM, around 21 ka), allowing comparison with palaeoclimate simulations currently being carried out as part of the fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change. The synthesis of the available MH and LGM climate reconstructions and their uncertainties, obtained using modern-analogue, regression and model-inversion techniques, is presented for four temperature variables and two moisture variables. Reconstructions of the same variables based on surface-pollen assemblages are shown to be accurate and unbiased. Reconstructed LGM and MH climate anomaly patterns are coherent, consistent between variables, and robust with respect to the choice of technique. They support a conceptual model of the controls of Late Quaternary climate change whereby the first-order effects of orbital variations and greenhouse forcing on the seasonal cycle of temperature are predictably modified by responses of the atmospheric circulation and surface energy balance. (orig.)

  6. A novel Ka-band coaxial transit-time oscillator with a four-gap buncher

    Song, Lili; He, Juntao; Ling, Junpu [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2015-05-15

    A novel Ka-band coaxial transit-time oscillator (TTO) with a four-gap buncher is proposed and investigated. Simulation results show that an output power of 1.27 GW and a frequency of 26.18 GHz can be achieved with a diode voltage of 447 kV and a beam current of 7.4 kA. The corresponding power efficiency is 38.5%, and the guiding magnetic field is 0.6 T. Studies and analysis indicate that a buncher with four gaps can modulate the electron beam better than the three-gap buncher in such a Ka-band TTO. Moreover, power efficiency increases with the coupling coefficient between the buncher and the extractor. Further simulation demonstrates that power efficiency can reach higher than 30% with a guiding magnetic field of above 0.5 T. Besides, the power efficiency exceeds 30% in a relatively large range of diode voltage from 375 kV to 495 kV.

  7. Think abstractly, smoke less: a brief construal-level intervention can promote self-control, leading to reduced cigarette consumption among current smokers.

    Chiou, Wen-Bin; Wu, Wen-Hsiung; Chang, Ming-Hsu

    2013-05-01

    Inadequate self-control has been linked to behavioural and impulse-control problems such as overeating, alcohol and drug abuse and smoking. Construal-level theory (CLT) suggests that a high-level construal (highlighting central goals associated with an event), relative to a low-level construal (highlighting means and resources), promotes self-control. Inspired by CLT, we examined whether smokers primed with a high-level (versus low-level) construal mind-set would show reductions in smoking that might be mediated by improved self-control. A single-factor (construal level: high, low, control) between-subjects design was employed. We used a widely employed why/how paradigm to induce high/low construal levels, whereby participants were asked to respond to questions about 'why' or 'how' they would maintain good physical health. Laboratory at Kaohsiung Medical University, Taiwan. A community sample consisting of 102 daily smokers participated in this experiment. The Stroop task measuring self-control was implemented after the construal-level manipulation. The dependent measure was actual cigarette consumption during an ostensible survey. Participants in a high-level construal mind-set smoked fewer cigarettes [mean = 1.3, 95% confidence interval (CI): 0.9, 1.7] than those in a low-level construal mind-set (mean = 2.6, 95% CI: 2.2, 3.0; P self-control (B = -1.14, 95% CI: -1.65, -0.74, P self-control that leads to reduced cigarette consumption. Thus, reminding smokers to think abstractly about health may be an effective strategy that could help them to smoke fewer cigarettes. © 2012 The Authors, Addiction © 2012 Society for the Study of Addiction.

  8. Will the Needs-Based Planning of Health Human Resources Currently Undertaken in Several Countries Lead to Excess Supply and Inefficiency?

    Basu, Kisalaya; Pak, Maxwell

    2016-01-01

    Recently, the emphasis on health human resources (HHR) planning has shifted away from a utilization-based approach toward a needs-based one in which planning is based on the projected health needs of the population. However, needs-based models that are currently in use rely on a definition of 'needs' that include only the medical circumstances of individuals and not personal preferences or other socio-economic factors. We examine whether planning based on such a narrow definition will maximize social welfare. We show that, in a publicly funded healthcare system, if the planner seeks to meet the aggregate need without taking utilization into consideration, then oversupply of HHR is likely because 'needs' do not necessarily translate into 'usage.' Our result suggests that HHR planning should track the healthcare system as access gradually improves because, even if health care is fully accessible, individuals may not fully utilize it to the degree prescribed by their medical circumstances. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Current studies on bacterospermia the leading cause of male infertility: a protégé and potential threat towards mans extinction

    Isaiah, Ibeh Nnana; Nche, Bikwe Thomas; Nwagu, Ibeh Georgina; Nnanna, Ibeh Isaiah

    2011-01-01

    Background: The current rise of male infertility associated with bacterospermia and urogenital infection has been on the increase amongst adult married males in Benin metropolis and a major cause of concern to male fertility and reproduction in Nigeria. Aim: To microbiologically isolate and study the infectious agent that has led to male infertility and also to study the percentage occurrence of bacteropsermia and urogenital caused infertility in adult married males in Benin metropolis Material and Method: using standard microbiological methods of isolating and identifying the organism, specimen was collected and processed which includes the susceptibility profile of isolates and sperm quality. In this study a total of 140 sperm samples was collected from patient who were referred from the consultant outpatient department of the University of Benin Teaching Hospital and then evaluated bacteriologically using standard bacterial cultural methods Results: Among the total cases, 92 (65.7%) showed at least one pathogen. Staphylococcus aureus (28.3%), Staphylococcus Saprophyticus (13.0%), Pseudomonas aerouginosa (6.5%), Escherichia Coli (19.6%) Proteus mirabilis (10.8%) Klebsiella spp (10.8%) and Proteus vulgaris (10.8%). Conclusion: There was an outstanding significant relationship between bacteriospermia and the rate of total motility and morphologically abnormal sperms, The percentage of morphologically normal sperm was lower in this study. Staphylococcus aureus Staphylococcus saprohyticus and Escherichia coli were the most common pathogen having negative effects on sperm motility and morphology in this study. PMID:22363079

  10. Current studies on bacterospermia the leading cause of male infertility: a protégé and potential threat towards mans extinction.

    Isaiah, Ibeh Nnana; Nche, Bikwe Thomas; Nwagu, Ibeh Georgina; Nnanna, Ibeh Isaiah

    2011-12-01

    The current rise of male infertility associated with bacterospermia and urogenital infection has been on the increase amongst adult married males in Benin metropolis and a major cause of concern to male fertility and reproduction in Nigeria. To microbiologically isolate and study the infectious agent that has led to male infertility and also to study the percentage occurrence of bacteropsermia and urogenital caused infertility in adult married males in Benin metropolis using standard microbiological methods of isolating and identifying the organism, specimen was collected and processed which includes the susceptibility profile of isolates and sperm quality. In this study a total of 140 sperm samples was collected from patient who were referred from the consultant outpatient department of the University of Benin Teaching Hospital and then evaluated bacteriologically using standard bacterial cultural methods Among the total cases, 92 (65.7%) showed at least one pathogen. Staphylococcus aureus (28.3%), Staphylococcus Saprophyticus (13.0%), Pseudomonas aerouginosa (6.5%), Escherichia Coli (19.6%) Proteus mirabilis (10.8%) Klebsiella spp (10.8%) and Proteus vulgaris (10.8%). There was an outstanding significant relationship between bacteriospermia and the rate of total motility and morphologically abnormal sperms, The percentage of morphologically normal sperm was lower in this study. Staphylococcus aureus Staphylococcus saprohyticus and Escherichia coli were the most common pathogen having negative effects on sperm motility and morphology in this study.

  11. High current plasma electron emitter

    Fiksel, G.; Almagri, A.F.; Craig, D.

    1995-07-01

    A high current plasma electron emitter based on a miniature plasma source has been developed. The emitting plasma is created by a pulsed high current gas discharge. The electron emission current is 1 kA at 300 V at the pulse duration of 10 ms. The prototype injector described in this paper will be used for a 20 kA electrostatic current injection experiment in the Madison Symmetric Torus (MST) reversed-field pinch. The source will be replicated in order to attain this total current requirement. The source has a simple design and has proven very reliable in operation. A high emission current, small size (3.7 cm in diameter), and low impurity generation make the source suitable for a variety of fusion and technological applications

  12. Lead poisoning

    Beijers, J A

    1952-01-01

    Three cases of acute lead poisoning of cattle herds via ingestion are reported, and reference is made to several other incidents of lead in both humans and animals. The quantity of lead which was found in the livers of the dead cows varied from 6.5 to 19 mg/kg, while 1160 mg/kg of lead in the liver was found for a young cow which was poisoned experimentally with 5 gms of lead acetate per day; hence, there appears to be great variability in the amounts deposited that can lead to intoxication and death. No evidence was found for a lead seam around the teeth, prophyrinuria, or basophil granules in the erythrocytes during acute or chronic lead poisoning of cattle or horses examined. Reference is made to attempts of finding the boundary line between increased lead absorption and lead intoxication in humans, and an examination of 60 laborers in an offset-printing office containing a great deal of inhalable lead (0.16 to 1.9 mg/cu m air) is reviewed. Physical deviation, basophylic granulation of erythrocytes, increased lead content of the urine, and porphyrinuria only indicate an increased absorption of lead; the use of the term intoxication is justified if, in addition, there are complaints of lack of appetite, constipation, fatigue, abdominal pain, and emaciation.

  13. Veretu retrobuum : [ka TPÜ AR kohvikust] / Allan Hmelnitski

    Hmelnitski, Allan

    2004-01-01

    "Ka mina eelistan kõigi söögikohtade seast Teaduste Akadeemia puhvetit, mis on 100% breezhnevi aegne disain - kunstnahast lett, ümmargused madalad lauad, pikk-pikk nahkdiivan, kurgid ja tomatid mis maitsevad hästi ja tugevalt, täpselt nagu aastal 85, hallides ülikondades vanemad härrad vestlemas põlevkivist ja paeklindi ajaloost. Vot see on tõeline petlik naiivsus, turvalisus, rahu, muretus ja stabiilsus nagu aastal 76 ema süles."

  14. Deriving and Interpreting Ka(karimusubi in Premodern Japanese

    Moreno MITROVIĆ

    2015-02-01

    Full Text Available This paper provides a new syntax and semantics for kakarimusubi (KM, a focus construction prominent in the grammar of Old Japanese (OJ and Early Middle (Classical Japanese (CJ, which diachronically developed into the interrogative construction in Modern Japanese (MdJ headed by the ka particle. Adopting Chierchia & Caponigro’s (2013 novel analysis of Free Relatives (FRs as embedded interrogatives, an FR-based analysis of KM is proposed so as to obtain a compositional semantic analysis of this focus construction as well as an account of the adnominal marking of the presuppositional musubi component of this grammatical construction.

  15. PODJETNIŠKA AKTIVNOST NA KOROŠKEM

    Marhl, Anja

    2010-01-01

    Da bi se posameznik podal na podjetniško pot mora zaznati poslovno priložnost, hkrati pa mora imeti tudi ustrezno znanje oziroma sposobnosti. Odločitev za podjetništvo je vedno osebna odločitev. Posameznik se mora sam odločiti ali bo deloval kot podjetnik, ali pa se bo ukvarjal s čim drugim. Koroška regija je ena izmed najstarejših slovenskih industrijskih regij. Prevladujejo predelovalne dejavnosti (proizvodnja kovin in kovinskih izdelkov, proizvodnja iz gume in plastike ter proizvodnja ...

  16. Lead Toxicity

    ... o Do not use glazed ceramics, home remedies, cosmetics, or leaded-crystal glassware unless you know that they are lead safe. o If you live near an industry, mine, or waste site that may have contaminated ...

  17. Kan Kaşanmak Deyimi Üzerine On The Idiom Kan Kaşanmak

    Yaşar ŞİMŞEK

    2013-03-01

    Full Text Available Mankind chose to tell his own feeling and thoughts with stereotyped words by using the expression facilities of his vernacular. The meaning of stereotyped words form as community's mutual thought's product by switching of the word or phrase's first meaning via simile. Idioms have a crucial place in regard to show the expression facilities in stereotyped words. That's why, the detection of entitiy in a language have an importance. In this essay, it will be dwelled on the idiom "kan kaşanmak"which is forgotten in these days, on the other hand; is mentioned oftenin Old Anatolian Turkish texts. The essay is composed of two parts. Inthe first part; the word kaşanmak's usage which is used in the meaningof "to urinate" in Uighur Turkish, Karakhanid Turkish, ChagataiTurkish, Qipchaq Turkish and Old Anatolian Turkish since Old Turkishperiod and today exists in Anatolian and Azerbaijan dialects, is going tobe tried to be shown with examples now that it forms a basis for "kankaşanmak" idiom.In the second part of the study, it will be dwelled on the idiom kankaşanmak's meaning transformation which is idiomatic form of theword kaşanmak, starting with the first meaning of it. The first meaningof the idiom kan kaşanmak means "to urinate blood, but later itbecomes a idiom by meaning transformation; in the meaning of"frighten to death, be scared as piss oneself, be scared as peeing bloodand this is going to be shown with examples. The study is going to befinished with showing the idiom's first meaning which is used in today'sAnatolian dialects usage " using an animal to carry load and animal'speeing blood because of the heavy burden" in the close meaning it isused for people too. İnsanoğlu, konuştuğu dilin ifade olanaklarını kullanarak, kendisine has duygu ve düşünceleri kalıplaşmış sözlerle anlatma yoluna gitmiştir. Kalıplaşmış sözlerin anlamı, sözcüğün ya da sözcük grubunun ilk anlamından mecaz yolu ile geçiş yaparak halk

  18. Analysis of Defective Interconnections of the 13 kA LHC Superconducting Bus Bars

    Granieri, P P; Bianchi, M; Breschi, M; Bottura, L; Willering, G

    2012-01-01

    The interconnections between Large Hadron Collider (LHC) main dipole and quadrupole magnets are made of soldered joints of two superconducting cables stabilized by a copper bus bar. The 2008 incident revealed the possible presence of defects in the interconnections of the 13 kA circuits that could lead to unprotected resistive transitions. Since then thorough experimental and numerical investigations were undertaken to determine the safe operating conditions for the LHC. This paper reports the analysis of experimental tests reproducing defective interconnections between main quadrupole magnets. A thermo-electromagnetic model was developed taking into account the complicated sample geometry. Close attention was paid to the physical description of the heat transfer towards helium, one of the main unknown parameters. The simulation results are reported in comparison with the measurements in case of static He I cooling bath. The outcome of this study constitutes a useful input to improve the stability assessment ...

  19. Relational Leading

    Larsen, Mette Vinther; Rasmussen, Jørgen Gulddahl

    2015-01-01

    This first chapter presents the exploratory and curious approach to leading as relational processes – an approach that pervades the entire book. We explore leading from a perspective that emphasises the unpredictable challenges and triviality of everyday life, which we consider an interesting......, relevant and realistic way to examine leading. The chapter brings up a number of concepts and contexts as formulated by researchers within the field, and in this way seeks to construct a first understanding of relational leading....

  20. Current sheet characteristics of a parallel-plate electromagnetic plasma accelerator operated in gas-prefilled mode

    Liu, Shuai; Huang, Yizhi; Guo, Haishan; Lin, Tianyu; Huang, Dong; Yang, Lanjun

    2018-05-01

    The axial characteristics of a current sheet in a parallel-plate electromagnetic plasma accelerator operated in gas-prefilled mode are reported. The accelerator is powered by a fourteen stage pulse forming network. The capacitor and inductor in each stage are 1.5 μF and 300 nH, respectively, and yield a damped oscillation square wave of current with a pulse width of 20.6 μs. Magnetic probes and photodiodes are placed at various axial positions to measure the behavior of the current sheet. Both magnetic probe and photodiode signals reveal a secondary breakdown when the current reverses the direction. An increase in the discharge current amplitude and a decrease in pressure lead to a decrease in the current shedding factor. The current sheet velocity and thickness are nearly constant during the run-down phase under the first half-period of the current. The current sheet thicknesses are typically in the range of 25 mm to 40 mm. The current sheet velocities are in the range of 10 km/s to 45 km/s when the discharge current is between 10 kA and 55 kA and the gas prefill pressure is between 30 Pa and 800 Pa. The experimental velocities are about 75% to 90% of the theoretical velocities calculated with the current shedding factor. One reason for this could be that the idealized snowplow analysis model ignores the surface drag force.

  1. Lead Test

    ... to do renovation and repair projects using lead-safe work practices to avoid creating more lead dust or ... in a dangerous area? Yes. If you are working in a potentially harmful environment with exposure to lead dust or fumes: Wash ...

  2. Review: Bilirubin pKa studies; new models and theories indicate high pKa values in water, dimethylformamide and DMSO

    Ostrow J

    2010-03-01

    Full Text Available Abstract Background Correct aqueous pKa values of unconjugated bilirubin (UCB, a poorly-soluble, unstable substance, are essential for understanding its functions. Our prior solvent partition studies, of unlabeled and [14C] UCB, indicated pKa values above 8.0. These high values were attributed to effects of internal H-bonding in UCB. Many earlier and subsequent studies have reported lower pKa values, some even below 5.0, which are often used to describe the behavior of UCB. We here review 18 published studies that assessed aqueous pKa values of UCB, critically evaluating their methodologies in relation to essential preconditions for valid pKa measurements (short-duration experiments with purified UCB below saturation and accounting for self-association of UCB. Results These re-assessments identified major deficiencies that invalidate the results of all but our partition studies. New theoretical modeling of UCB titrations shows remarkable, unexpected effects of self-association, yielding falsely low pKa estimates, and provides some rationalization of the titration anomalies. The titration behavior reported for a soluble thioether conjugate of UCB at high aqueous concentrations is shown to be highly anomalous. Theoretical re-interpretations of data in DMSO and dimethylformamide show that those indirectly-derived aqueous pKa values are unacceptable, and indicate new, high average pKa values for UCB in non-aqueous media (>11 in DMSO and, probably, >10 in dimethylformamide. Conclusions No reliable aqueous pKa values of UCB are available for comparison with our partition-derived results. A companion paper shows that only the high pKa values can explain the pH-dependence of UCB binding to phospholipids, cyclodextrins, and alkyl-glycoside and bile salt micelles.

  3. Rationalization of the pKa values of alcohols and thiols using atomic charge descriptors and its application to the prediction of amino acid pKa's.

    Ugur, Ilke; Marion, Antoine; Parant, Stéphane; Jensen, Jan H; Monard, Gerald

    2014-08-25

    In a first step toward the development of an efficient and accurate protocol to estimate amino acids' pKa's in proteins, we present in this work how to reproduce the pKa's of alcohol and thiol based residues (namely tyrosine, serine, and cysteine) in aqueous solution from the knowledge of the experimental pKa's of phenols, alcohols, and thiols. Our protocol is based on the linear relationship between computed atomic charges of the anionic form of the molecules (being either phenolates, alkoxides, or thiolates) and their respective experimental pKa values. It is tested with different environment approaches (gas phase or continuum solvent-based approaches), with five distinct atomic charge models (Mulliken, Löwdin, NPA, Merz-Kollman, and CHelpG), and with nine different DFT functionals combined with 16 different basis sets. Moreover, the capability of semiempirical methods (AM1, RM1, PM3, and PM6) to also predict pKa's of thiols, phenols, and alcohols is analyzed. From our benchmarks, the best combination to reproduce experimental pKa's is to compute NPA atomic charge using the CPCM model at the B3LYP/3-21G and M062X/6-311G levels for alcohols (R(2) = 0.995) and thiols (R(2) = 0.986), respectively. The applicability of the suggested protocol is tested with tyrosine and cysteine amino acids, and precise pKa predictions are obtained. The stability of the amino acid pKa's with respect to geometrical changes is also tested by MM-MD and DFT-MD calculations. Considering its strong accuracy and its high computational efficiency, these pKa prediction calculations using atomic charges indicate a promising method for predicting amino acids' pKa in a protein environment.

  4. Past climate variability between 97 and 7 ka reconstructed from a multi proxy speleothem record from Western Cuba

    Winterhalder, Sophie; Scholz, Denis; Mangini, Augusto; Spötl, Christoph; Jochum, Klaus Peter; Pajón, Jesús M.

    2016-04-01

    The tropical hydrological cycle plays a key role in regulating global climate, mainly through the export of heat and moisture to higher latitudes, and is highly sensitive to climate change, for instance due to changes in the position of the Intertropical Convergence Zone (ITCZ). Previous work on Caribbean stalagmites suggests a strong connection of precipitation variability to North Atlantic (NA) sea surface temperatures on multidecadal to millenial timescales (Fensterer et al., 2012; Fensterer et al., 2013; Winter et al., 2011). Cold phases in the NA potentially lead to a southward shift of the ITCZ and thus drier conditions in Cuba. On orbital timescales, Cuban stalagmites suggest a relation of speleothem δ18O values with the δ18O value of Caribbean surface waters (Fensterer et al., 2013). Here we present an expansion of the Cuban speleothem record covering the whole last glacial period from the end of MIS5c (97 ka BP) until 7 ka with hiatuses between 93-80 ka, 37-35 ka and 13-10 ka. Stalagmite Cuba medio (CM) has been precisely dated with 60 230Th/U-ages, mainly performed by the MC-ICPMS technique. The δ18O and δ13C records are completed by a continuous, high resolution LA-ICPMS trace element profile. These data allow for the first time to establish a multi-proxy climate reconstruction for the North Western Caribbean at decadal to centennial resolution for this period. The long-term variability of the δ18O values probably reflects rainfall amount in Cuba. The response to some Dansgaard/Oeschger and Heinrich stadials confirms the previously observed correlation between Caribbean and NA climate variability. However, this connection is not clearly imprinted throughout the record. Furthermore, trace elements, such as Mg, do not proof without ambiguity drier conditions in Cuba during NA cold events, such as the Heinrich stadials. This suggests that climate variability in Cuba was more complex during the last 100ka, and that the NA was not the only driving factor

  5. Expansion of plasma of electrically exploding single copper wire under 4.5 kA-9.5 kA/wire

    Li Yexun; Yang Libing; Sun Chengwei

    2003-01-01

    The experimental system for electrically exploding single metal wire has been designed and manufactured. Expansion of the dense plasma column formed from an electrically exploding Cu wire of diameter 30 μm has been studied with a high-speed photographer to obtain the time-dependent radius (R-t) curve. The experimental results demonstrate that the mean expansion rate of the dense plasma column is 1.94 μm/ns, 2.6 μm/ns and 3.75 μm/ns according to the peak pulse current 4.5 kA, 7 kA and 9.5 kA respectively. The results can be beneficial to giving a profound understanding of the early stage of wire-array Z-pinch physics and to improvement on their design

  6. Full Ka Band Waveguide-to-Microstrip Inline Transition Design

    Li, Jianxing; Li, Lei; Qiao, Yu; Chen, Juan; Chen, Jianzhong; Zhang, Anxue

    2018-05-01

    In this paper, a compact and broadband inline waveguide-to-microstrip transition is proposed to cover the full Ka band. The transition can be segmented from the electric point of view into three building blocks, comprising a microstrip line to rectangular coaxial line, a wedged rectangular coaxial line to ridged waveguide, and a final tapered ridged waveguide impedance transformer to standard waveguide. Both good electrical performance and simple modular assembly without any soldering have been simultaneously obtained. The validation of the design concept has been conducted by numerical simulations and experimental measurements. The experimental results of a fabricated back-to-back transition prototype coincide with the simulated results. It shows that the proposed transition achieves good return loss of lower than 15.5 dB and low insertion loss with a fluctuation between 0.23 to 0.60 dB across the entire Ka band. Details of design considerations and operation mechanism as well as simulation and measurement results are presented.

  7. Plasma cutting or laser cutting. Plasma setsudan ka laser setsudan ka

    Nakamura, A. (Tanaka Engineering Works Ltd., Saitama (Japan))

    1991-05-01

    Comparisons and discussions were made on the plasma cutting and laser cutting in sheet steel cutting, referring partly to gas cutting. Historically, the cutting has been developed from gas, plasma, and laser in that order, and currently these three methods are used mixedly. Generally, the plasma cutting is superior in cutting speed, but inferior in cut face quality, and it requires measures of dust collection. Due to high accuracy and quality in cut face, the laser cutting has been practically used for quite some time in the thin sheet industry, but medium to thick sheet cutting had a problem of unavailability of high output laser suitable for these ranges. However, the recent technologies have overcome the problem as a result of development at the authors {prime} company of a 2 kW class laser cutter capable of cutting 19 mm thick sheet. The cutter has been proven being particularly excellent in controllability. Choice of whether plasma or laser would depend upon which priority is to be taken, cost or accuracy. 15 figs., 3 tabs.

  8. Challenges in pKa Predictions for Proteins: The case of Asp213 in Human Proteinase 3

    Hajjar, Eric; Dejaegere, Annick; Reuter, Nathalie

    2009-09-01

    Knowledge of the protonation states of the ionizable residues in an enzyme is a prerequisite to an accurate description of its structure and mechanism. In practice, the use of the inappropriate protonation state for an amino acid in a molecular modeling computation (e.g., molecular dynamics simulation) is likely to lead to unrealistic results. Although methods using solvers of the linearized Poisson-Boltzmann equation have proven to yield accurate pKa predictions, they bear a number of limitations. They are quite demanding in terms of computational power and are sensitive to representation of the charges and their position (force field and protein conformation). Moreover they depend on the choice of a dielectric constant for the protein interior. In this manuscript, we describe the difficulties met when trying to predict the protonation state of a buried amino acid, located in a protein for which very little biochemical data is available. Such a case is highly representative of the challenges faced in theoretical biology studies. Proteinase 3 (PR3) is an enzyme involved in proteolytic events associated with inflammation. It is a potential target in the development of new anti-inflammatory therapeutic strategies. We report the results of pKa predictions of the aspartic acid 213 of PR3 with a FDPB solver. We probed the influence of the choice of the dielectric constant for the protein interior ɛp and the benefits of conformational sampling by molecular dynamics (MD) on the pKa prediction of this carboxylate group. Using only the FDPB calculations, we could not conclude on the protonation state of Asp213. MD simulations confronted to knowledge of the ligand-binding and reaction mechanism led us to decide on a protonated form of this aspartic acid. We also demonstrate that the use of the wrong protonation state leads to an unreliable structural model for PR3. pKa prediction with a fast empirical method yielded a pKa of 8.4 for Asp213, which is in agreement with our

  9. Design of a 30 m long 1 kA 10 kV YBCO cable

    Rostila, L [Institute of Electromagnetics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere (Finland); Lehtonen, J [Institute of Electromagnetics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere (Finland); Masti, M [Institute of Electromagnetics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere (Finland); Lallouet, N [Nexas France, rue Mozart 4-10, 92587 Clichy (France); Saugrain, J-M [Nexas France, rue Mozart 4-10, 92587 Clichy (France); Allais, A [Nexans Deutschland Industries GmbH and Co. KG, Kabelkamp 20, D-30179 Hannover (Germany); Schippl, K [Nexans Deutschland Industries GmbH and Co. KG, Kabelkamp 20, D-30179 Hannover (Germany); Schmidt, F [Nexans Deutschland Industries GmbH and Co. KG, Kabelkamp 20, D-30179 Hannover (Germany); Balog, G [Nexans Norway, PO Box 6450, Etterstad, N-0605, Oslo, Norway (Norway); Marot, G [Air Liquide DTA, 2 rue de Clemenciere BP15, 38360 Sassenage (France); Ravex, A [Air Liquide DTA, 2 rue de Clemenciere BP15, 38360 Sassenage (France); Usoskin, A [European High Temperature Superconductors Gmbh and Co. KG, Windausweg 2, 37037 Goettingen (Germany); Goemoery, F [Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska cesta 9, 84104 Bratislava (Slovakia); Klincok, B [Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska cesta 9, 84104 Bratislava (Slovakia); Souc, J [Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska cesta 9, 84104 Bratislava (Slovakia); Freyhardt, H C [Institute of Materialphysic, University of Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen (Germany)

    2006-04-15

    In this paper a 30 m long one-phase coaxial YBCO cable with 1 kA transport current and 10 kV operating voltage was designed for the Super3C project to check the feasibility of YBCO tapes for low-loss cables. The final design incorporates cryogenic, mechanical and electromagnetic aspects. The electromagnetic losses during normal operation must be minimized. The cryogenic design must also take into account the generation of heat during short circuit conditions. Mechanical restrictions set the minimum gaps between the coated conductor tapes and the minimum lay angles in order to make the cabling feasible and to enable handling of the cable. The design of the electric insulation should be according to the international standard as far as applicable. The final design has to take into account all of the above restrictions.

  10. Long-term monitoring of Sgr A* at 7 mm with VERA and KaVA

    Akiyama, K.; Kino, M.; Sohn, B.; Lee, S.; Trippe, S.; Honma, M.

    2014-05-01

    We present the results of radio monitoring observations of Sgr A* at 7 mm (i.e. 43 GHz) with the VLBI Exploration of Radio Astrometry (VERA), which is a VLBI array in Japan. VERA provides angular resolution on millisecond scales, resolving structures within 100 Schwarzschild radii of Sgr A* , similar to the Very Large Baseline Array (VLBA). We performed multi-epoch observations of Sgr A* in 2005 - 2008, and started monitoring it again with VERA from 2013 January to trace the current G2 encounter event. Our preliminary results in 2013 show that Sgr A* on mas scales has been in an ordinary state as of August 2013, although some fraction of the G2 cloud already passed the pericenter of Sgr A* in April 2013. We will continue monitoring Sgr A* with VERA and the newly developed KaVA (KVN and VERA Array).

  11. Design of a 30 m long 1 kA 10 kV YBCO cable

    Rostila, L; Lehtonen, J; Masti, M; Lallouet, N; Saugrain, J-M; Allais, A; Schippl, K; Schmidt, F; Balog, G; Marot, G; Ravex, A; Usoskin, A; Goemoery, F; Klincok, B; Souc, J; Freyhardt, H C

    2006-01-01

    In this paper a 30 m long one-phase coaxial YBCO cable with 1 kA transport current and 10 kV operating voltage was designed for the Super3C project to check the feasibility of YBCO tapes for low-loss cables. The final design incorporates cryogenic, mechanical and electromagnetic aspects. The electromagnetic losses during normal operation must be minimized. The cryogenic design must also take into account the generation of heat during short circuit conditions. Mechanical restrictions set the minimum gaps between the coated conductor tapes and the minimum lay angles in order to make the cabling feasible and to enable handling of the cable. The design of the electric insulation should be according to the international standard as far as applicable. The final design has to take into account all of the above restrictions

  12. Advanced test accelerator (ATA), a 50 MeV, 10 kA induction linac

    Reginato, L.

    1983-01-01

    The ATA is an induction accelerator designed to produce 70 ns pulses of electrons at currents of 10 kA and energies in excess of 50 MeV. The accelerator is capable of operating at an average rate of 5 Hz or at 1 kHz for ten pulses. The parameters were chosen primarily to provide the experimental basis for advancing the understanding of electron beam propagation physics. The 85 m accelerator has been under construction for the past four years and has adopted mainly an improved version of the ETA technology to satisfy the required parameters. Initial operation of the facility and the energy conversion system from primary power to axial electric field will be described; recent advances in magnetic switching which have been incorporated in the innector will also be discussed

  13. pKa predictions for proteins, RNAs, and DNAs with the Gaussian dielectric function using DelPhi pKa.

    Wang, Lin; Li, Lin; Alexov, Emil

    2015-12-01

    We developed a Poisson-Boltzmann based approach to calculate the pKa values of protein ionizable residues (Glu, Asp, His, Lys and Arg), nucleotides of RNA and single stranded DNA. Two novel features were utilized: the dielectric properties of the macromolecules and water phase were modeled via the smooth Gaussian-based dielectric function in DelPhi and the corresponding electrostatic energies were calculated without defining the molecular surface. We tested the algorithm by calculating pKa values for more than 300 residues from 32 proteins from the PPD dataset and achieved an overall RMSD of 0.77. Particularly, the RMSD of 0.55 was achieved for surface residues, while the RMSD of 1.1 for buried residues. The approach was also found capable of capturing the large pKa shifts of various single point mutations in staphylococcal nuclease (SNase) from pKa-cooperative dataset, resulting in an overall RMSD of 1.6 for this set of pKa's. Investigations showed that predictions for most of buried mutant residues of SNase could be improved by using higher dielectric constant values. Furthermore, an option to generate different hydrogen positions also improves pKa predictions for buried carboxyl residues. Finally, the pKa calculations on two RNAs demonstrated the capability of this approach for other types of biomolecules. © 2015 Wiley Periodicals, Inc.

  14. Malama I Ka `Aina: Fostering the Culture-Science connection

    Bruno, B.; Chinn, P.

    2005-12-01

    The Malama I Ka `Aina Project (Caring for the land, or sustainability) aims to improve and expand the education of Hawai`i's children by developing and disseminating standards-based, culturally relevant science curricular materials based on an understanding and appreciation of the ways in which traditional Hawaiians interacted with their environment for sustainability. Key concepts include the role of water and the ahupua`a (traditional Hawaiian system of land management), and a culture-based sense of place that includes knowledge of and connection to the land. Elementary, middle, high school and University of Hawai`i teachers work together to develop and implement curricula that are especially relevant to a particular school's science program and issues, e.g., invasive species, students, community and/or geographical location. Participants (typically a mix of teachers, education majors and science majors) enroll in Malama I Ka `Aina, a three-credit course offered through the University of Hawai`i`s Dept. of Curriculum Studies and applicable toward a Bachelor's or Master's degree. This course (team taught by scientists, cultural experts and educational professionals) enables participants to: (1) Study Hawai`i`s unique geology, geography and environmental issues in the context of Hawaiian culture and post Western contact; (2) Use course knowledge to develop, teach and assess Hawaii-oriented, project-based, inquiry activities that address the Hawaii Science Content Standards; (3) Gain an appreciation for the scientific method, and the curiosity that drives science (4) Use educational technology such as PowerPoint, graphing packages and web authoring software to develop electronic resources for educational activities. A sample of the lessons developed by course participants can be found on http://malama.hawaii.edu/schools/index2.html. This project is based at the University of Hawai`i College of Education and funded by an award to P. Chinn by the US Department of

  15. Potentiometric pKa Determination of Piroxicam and Tenoxicam in Acetonitrile-Water Binary Mixtures

    Çubuk Demiralay, Ebru; Yılmaz, Hülya

    2012-01-01

    Abstract: Ionization constant (pKa) is one among the parameter to be estimated with accuracy, irrespective of solubility constraints. In the present study, acid-base behaviour of the piroxicam and tenoxicam was studied. By using the potentiometric method, pKa values of piroxicam and tenoxicam have been determined in different percentage of acetonitrile-water binary mixtures (acetonitrile content between 30 and 45% in volume). Aqueous pKa values of these compounds were calculated by mole fract...

  16. Snovanje in konstruiranje nadstreška za lahka gospodarska vozila

    Čirić, Sebastijan

    2015-01-01

    Diplomska naloga opisuje primer snovanja in konstruiranja nadstreška za lahka gospodarska vozila. Naloga vsebuje statični preračun nadstreška sprogramom Scia Engineer 2011.1 in izdelavo modela nadstreška ter tehnično dokumentacijo v programu Pro Engineer 5.0. Rezultati statičnega preračuna so analizirane vrednosti povesa in napetosti.

  17. Leading Democratically

    Brookfield, Stephen

    2010-01-01

    Democracy is the most venerated of American ideas, the one for which wars are fought and people die. So most people would probably agree that leaders should be able to lead well in a democratic society. Yet, genuinely democratic leadership is a relative rarity. Leading democratically means viewing leadership as a function or process, rather than…

  18. Study of two step constant current charging method with EV`s valve-regulated lead acid batteries for nighttime load leveling; Yakan denryoku wo yuko katsuyo dekiru denki jidoshayo namari denchi no nidantei denryu judenho no kaihatsu

    Ikeya, T.; Mita, Y.; Iwahori, T. [Central Research Institute of Electric Power Industry, Tokyo (Japan); Iwasaki, M.; Takagi, S.; Sugii, Y.; Yada, M.; Sakabe, T.; Kosaka, E.; Tsuchiya, H.; Kanetsuki, M.; Nasu, H.; Ono, M.; Adachi, K.; Narisoko, H.; Nishiyama, K.

    1997-02-01

    In the constant-current/constant-voltage charging method that has been in application for EV (electric vehicle) lead-acid batteries, power load is generated only at the initial part of the charging process, and therefore the method cannot be said to be sufficiently contributory to the levelling of power loads. In this report, a proposed 2-step constant-current charging method is assessed for applicability, and another charging method is introduced, which extends battery life and utilizes low-cost night-time power more effectively. It is found that the proposed 2-step constant-current charging method (1st step: 12A, 2nd step: 3A) completes the charging process in eight hours, that it assumes a charging pattern more suitable for contributing to the effective use of night-time power than the conventional method, and that it extends the battery life of approximately 170 cycles to approximately 300 cycles. In a study seeking for a charging method capable of utilizing night-time power more efficiently, the 1st-step current of 12A is increased to 30A for shortening the charging time, and then it is found that this change extends the battery cycle life and improves on charging efficiency. The conclusion is that possibilities are high that an increase in the 1st-step current prolongs the battery life cycle and shortens the charting time. 16 refs., 28 figs., 8 tabs.

  19. Highly Perturbed pKa Values in the Unfolded State of Hen Egg White Lysozyme

    Bradley, John; O'Meara, Fergal; Farrell, Damien; Nielsen, Jens Erik

    2012-01-01

    The majority of pKa values in protein unfolded states are close to the amino acid model pKa values, thus reflecting the weak intramolecular interactions present in the unfolded ensemble of most proteins. We have carried out thermal denaturation measurements on the WT and eight mutants of HEWL from pH 1.5 to pH 11.0 to examine the unfolded state pKa values and the pH dependence of protein stability for this enzyme. The availability of accurate pKa values for the folded state of HEWL and separa...

  20. Franchisingkäsikirjan tuottaminen käytettyjen valokuvaustarvikkeiden verkkokaupalle

    Heikkinen, Antti

    2015-01-01

    Tämän opinnäytetyön tarkoituksena oli luoda selkeä ja helppokäyttöinen franchisingkäsikirja Kameratori Oy:lle. Kameratori on vuonna 2010 perustettu käytettyyn valokuvauskalustoon keskittyvä verkkokauppa, joka myy Tampereen toimitiloista käsin kuntotarkistettua kuvauskalustoa Suomeen ja maailmalle. Franchisingkäsikirjaan on dokumentoitu Kameratori.fi-verkkosivuston käyttöön tarvittava ohjeistus. Käsikirja on yksi olennaisimmista dokumenteista franchisingantajan ja -ottajien...

  1. [Study on the method for the determination of trace boron, molybdenum, silver, tin and lead in geochemical samples by direct current arc full spectrum direct reading atomic emission spectroscopy (DC-Arc-AES)].

    Hao, Zhi-hong; Yao, Jian-zhen; Tang, Rui-ling; Zhang, Xue-mei; Li, Wen-ge; Zhang, Qin

    2015-02-01

    The method for the determmation of trace boron, molybdenum, silver, tin and lead in geochemical samples by direct current are full spectrum direct reading atomic emission spectroscopy (DC-Arc-AES) was established. Direct current are full spectrum direct reading atomic emission spectrometer with a large area of solid-state detectors has functions of full spectrum direct reading and real-time background correction. The new electrodes and new buffer recipe were proposed in this paper, and have applied for national patent. Suitable analytical line pairs, back ground correcting points of elements and the internal standard method were selected, and Ge was used as internal standard. Multistage currents were selected in the research on current program, and each current set different holding time to ensure that each element has a good signal to noise ratio. Continuous rising current mode selected can effectively eliminate the splash of the sample. Argon as shielding gas can eliminate CN band generating and reduce spectral background, also plays a role in stabilizing the are, and argon flow 3.5 L x min(-1) was selected. Evaporation curve of each element was made, and it was concluded that the evaporation behavior of each element is consistent, and combined with the effects of different spectrographic times on the intensity and background, the spectrographic time of 35s was selected. In this paper, national standards substances were selected as a standard series, and the standard series includes different nature and different content of standard substances which meet the determination of trace boron, molybdenum, silver, tin and lead in geochemical samples. In the optimum experimental conditions, the detection limits for B, Mo, Ag, Sn and Pb are 1.1, 0.09, 0.01, 0.41, and 0.56 microg x g(-1) respectively, and the precisions (RSD, n=12) for B, Mo, Ag, Sn and Pb are 4.57%-7.63%, 5.14%-7.75%, 5.48%-12.30%, 3.97%-10.46%, and 4.26%-9.21% respectively. The analytical accuracy was

  2. FIZIČKA AKTIVNOST I ŠEĆERNA BOLEST

    BARETIĆ, MAJA

    2017-01-01

    Sve veća učestalost šećerne bolesti povezuje se s prihvaćanjem netradicionalnih načina prehrane i prakticiranjem „sjedilačkog načina života“. Liječenje šećerne bolesti sastoji se od promjene životnog stila što uključuje promjenu fizičke aktivnosti, tipa i učestalosti prehrane te uzimanje specifi čne terapije. Fizička aktivnost je dio temeljnog liječenja dijabetesa; ima dokazane koristi u smanjenju inzulinske rezistencije, poboljšanju glikemijske kontrole, lipidnog profi la, u normalizaciji tj...

  3. Miniaturized Ka-Band Dual-Channel Radar

    Hoffman, James P.; Moussessian, Alina; Jenabi, Masud; Custodero, Brian

    2011-01-01

    Smaller (volume, mass, power) electronics for a Ka-band (36 GHz) radar interferometer were required. To reduce size and achieve better control over RFphase versus temperature, fully hybrid electronics were developed for the RF portion of the radar s two-channel receiver and single-channel transmitter. In this context, fully hybrid means that every active RF device was an open die, and all passives were directly attached to the subcarrier. Attachments were made using wire and ribbon bonding. In this way, every component, even small passives, was selected for the fabrication of the two radar receivers, and the devices were mounted relative to each other in order to make complementary components isothermal and to isolate other components from potential temperature gradients. This is critical for developing receivers that can track each other s phase over temperature, which is a key mission driver for obtaining ocean surface height. Fully hybrid, Ka-band (36 GHz) radar transmitter and dual-channel receiver were developed for spaceborne radar interferometry. The fully hybrid fabrication enables control over every aspect of the component selection, placement, and connection. Since the two receiver channels must track each other to better than 100 millidegrees of RF phase over several minutes, the hardware in the two receivers must be "identical," routed the same (same line lengths), and as isothermal as possible. This level of design freedom is not possible with packaged components, which include many internal passive, unknown internal connection lengths/types, and often a single orientation of inputs and outputs.

  4. Bioactive Natural Product and Superacid Chemistry for Lead Compound Identification: A Case Study of Selective hCA III and L-Type Ca2+ Current Inhibitors for Hypotensive Agent Discovery

    Hélène Carreyre

    2017-05-01

    Full Text Available Dodoneine (Ddn is one of the active compounds identified from Agelanthus dodoneifolius, which is a medicinal plant used in African pharmacopeia and traditional medicine for the treatment of hypertension. In the context of a scientific program aiming at discovering new hypotensive agents through the original combination of natural product discovery and superacid chemistry diversification, and after evidencing dodoneine’s vasorelaxant effect on rat aorta, superacid modifications allowed us to generate original analogues which showed selective human carbonic anhydrase III (hCA III and L-type Ca2+ current inhibition. These derivatives can now be considered as new lead compounds for vasorelaxant therapeutics targeting these two proteins.

  5. Food safety knowledge on the Bt mutant protein Cry8Ka5 employed in the development of coleopteran-resistant transgenic cotton plants.

    Farias, Davi F; Peijnenburg, Ad A C M; Grossi-de-Sá, Maria F; Carvalho, Ana F U

    2015-01-01

    Insecticidal Cry proteins from Bacillus thuringiensis (Bt) have been exploited in the development of genetically modified (GM) crops for pest control. However, several pests are still difficult to control such as the coleopteran boll weevil Anthonomus grandis. By applying in vitro molecular evolution to the cry8Ka1 gene sequence, variants were generated with improved activity against A. grandis. Among them, Cry8Ka5 mutant protein showed coleoptericidal activity 3-fold higher (LC50 2.83 μg/mL) than that of the original protein (Cry8Ka1). Cry8Ka5 has been used in breeding programs in order to obtain coleopteran-resistant cotton plants. Nevertheless, there is some concern in relation to the food safety of transgenic crops, especially to the heterologously expressed proteins. In this context, our research group has performed risk assessment studies on Cry8Ka5, using the tests recommended by Codex as well as tests that we proposed as alternative and/or complementary approaches. Our results on the risk analysis of Cry8Ka5 taken together with those of other Cry proteins, point out that there is a high degree of certainty on their food safety. It is reasonable to emphasize that most safety studies on Cry proteins have essentially used the Codex approach. However, other methodologies would potentially provide additional information such as studies on the effects of Cry proteins and derived peptides on the indigenous gastrointestinal microbiota and on intestinal epithelial cells of humans. Additionally, emerging technologies such as toxicogenomics potentially will offer sensitive alternatives for some current approaches or methods.

  6. Leading change.

    2017-02-27

    In response to feedback from nursing, midwifery and other care staff who wanted to understand better how the Leading Change, Adding Value framework applies to them, NHS England has updated its webpage to include practice examples.

  7. Increasing Diversity in STEM through Ka Hikina O Ka Lā Summer Bridge Program for Native Hawaiian Students

    Coopersmith, A.; Cie, D. K.; Calder, S.; Naho`olewa, D.; Rai, B.

    2014-12-01

    The Advanced Technology Solar Telescope (ATST) Mitigation Initiative and the Kahikina O Ka Lā Program are NSF-funded projects at the University of Hawai`i Maui College. These projects offer instruction and activities intended to increase diversity in STEM careers. Ke Alahaka, the 2014 summer bridge program, was offered to Native Hawaiian high-school students who indicated an interest in STEM areas. Content workshops were offered in Marine Science, Physics, Biotechnology, and Computer Science and Engineering as well as a Hawaiian Studies course designed to provide a cultural context for the STEM instruction. Focus groups and other program assessments indicate that 50% of the students attending the workshops intend to pursue a STEM major during their undergraduate studies.

  8. High-Current Plasma Electron Sources

    Gushenets, J.Z.; Krokhmal, V.A.; Krasik, Ya. E.; Felsteiner, J.; Gushenets, V.

    2002-01-01

    In this report we present the design, electrical schemes and preliminary results of a test of 4 different electron plasma cathodes operating under Kg h-voltage pulses in a vacuum diode. The first plasma cathode consists of 6 azimuthally symmetrically distributed arc guns and a hollow anode having an output window covered by a metal grid. Plasma formation is initiated by a surface discharge over a ceramic washer placed between a W-made cathode and an intermediate electrode. Further plasma expansion leads to a redistribution of the discharge between the W-cathode and the hollow anode. An accelerating pulse applied between the output anode grid and the collector extracts electrons from this plasma. The operation of another plasma cathode design is based on Penning discharge for preliminary plasma formation. The main glow discharge occurs between an intermediate electrode of the Penning gun and the hollow anode. To keep the background pressure in the accelerating gap at P S 2.5x10 4 Torr either differential pumping or a pulsed gas puff valve were used. The operation of the latter electron plasma source is based on a hollow cathode discharge. To achieve a sharp pressure gradient between the cathode cavity and the accelerating gap a pulsed gas puff valve was used. A specially designed ferroelectric plasma cathode initiated plasma formation inside the hollow cathode. This type of the hollow cathode discharge ignition allowed to achieve a discharge current of 1.2 kA at a background pressure of 2x10 4 Torr. All these cathodes were developed and initially tested inside a planar diode with a background pressure S 2x10 4 Torr under the same conditions: accelerating voltage 180 - 300 kV, pulse duration 200 - 400 ns, electron beam current - 1 - 1.5 kA, and cross-sectional area of the extracted electron beam 113 cm 2

  9. Global Ocean Data Quality Assessment of SARAL/AltiKa GDR products

    Picot, Nicolas; Prandi, Pierre; desjonqueres, jean-damien

    2015-04-01

    The SARAL mission was successfully launched on February, 5th 2013 and cycle 1 started a few days later on March 14th. For more than 2 years, the Ka-band altimeter and dual frequency radiometer on board have been collecting high quality ocean topography measurements. Within the first months of the mission, a first patch (P1) was developed to correct some small anomalies detected in the products and to account for in-flight calibration data. At the beginning of year 2014, a second patch (P2) was produced (applied from cycle 10 pass 407 on OGDR data and from pass 566 on IGDR data) and the all GDR produced before this were reprocessed in order to deliver a consistent dataset to users. This new version of the products provides, among other changes, important improvements regarding radiometer data processing, sea-state bias and wind speed. Since the beginning of the mission, data quality assessment of OGDR, IGDR and GDR data has been routinely performed at CNES and CLS (as part of the CNES SALP project). We will present the main results of the data quality assessment over ocean based on SARAL/AltiKa GDR data reprocessed using the homogeneous P2 version. The main data quality metrics presented will include: Data availability and validity, Monitoring of the main altimeter and radiometer parameters and comparisons to other altimeter missions such as OSTM/Jason-2, Mission performance through mono-mission crossovers analysis, Investigation of inter-mission biases and large-scale regional differences from multi-mission crossovers between SARAL and Jason-2. Monitoring of the global mean SLA and comparison to Jason-2 Finally, we will present the new product version standard that is currently under development on CNES side.

  10. High-current railgap studies

    Druce, R.; Gordon, L.; Hofer, W.; Wilson, M.

    1983-06-03

    Characteristics of a 40-kV, 750-kA, multichannel rail gap are presented. The gap is a three electrode, field-distortion-triggered design, with a total switch inductance of less than 10 nH. At maximum ratings, the gap typically switches 10 C per shot, at 700 kA, with a jitter of less than 2 ns. Image-converter streak photographs were used to study channel evolution and current division. Transient gas-pressure measurements were made to investigate the arc generated shocks and to detect single channel failure. Channel current sharing and simultaneity are described and their effects on the switch inductance and lifetime are discussed. Lifetime tests of the rail gap were performed. Degradation in the channel current-sharing and erosion measurements are discussed.

  11. High-current railgap studies

    Druce, R.; Gordon, L.; Hofer, W.; Wilson, M.

    1983-06-01

    Characteristics of a 40-kV, 750-kA, multichannel rail gap are presented. The gap is a three electrode, field distortion triggered design, with a total switch inductance of less than 10 nH. At maximum ratings, the gap typically switches 10 C per shot, at 700 kA, with a jitter of less than 2 ns. Channel evolution and current division were studied on image converter streak photographs. Transient gas pressure measurements were made to investigate the arc generated shocks and to detect single channel failure. Channel current sharing and simultaneity are described and their effects on the switch inductance in the channel current sharing and erosion measurements are discussed.

  12. A 150-ka-long record for the volcano-tectonic deformation of Central Anatolian Volcanic Province

    Karabacak, Volkan; Tonguç Uysal, I.; Ünal-İmer, Ezgi; Mutlu, Halim; Zhao, Jian-xin

    2017-04-01

    The Anatolian Block represents one of the most outstanding examples of intra-plate deformation related to continental collision. Deformation related to the convergence of the Afro-Arabian continent toward north gives rise to widespread and intense arc volcanism in the Central Anatolia. All the usual studies on dating the volcano-tectonic deformation of the region are performed entirely on volcanic events of the geological record resulted in eruptions. However, without volcanic eruption, magma migration and related fluid pressurization also generate crustal deformation. In the current study has been funded by the Scientific and Technological Research Council of Turkey with the project no. 115Y497, we focused on fracture systems and their carbonate veins around the Ihlara Valley (Cappadocia) surrounded by well-known volcanic centers with latest activities of the southern Central Anatolian Volcanic Province. We dated 37 samples using the Uranium-series technique and analyzed their isotope systematics from fissure veins, which are thought to be controlled by the young volcanism in the region. Our detailed fracture analyses in the field show that there is a regional dilatation as a result of a NW-SE striking extension which is consistent with the results of recent GPS studies. The Uranium-series results indicate that fracture development and associated carbonate vein deposition occurred in the last 150 ka. Carbon and oxygen isotope systematics have almost remained unchanged in the studied time interval. Although veins in the region were precipitated from fluids primarily of meteoric origin, fluids originating from water-rock interaction also contribute for the deposition of carbonate veins. The age distribution indicates that the crustal deformation intensified during 7 different period at about 4.7, 34, 44, 52, 83, 91, 149 ka BP. Four of these periods (4.7, 34, 91, 149 ka BP) correspond to the volcanic activities suggested in the previous studies. The three crustal

  13. Ravimiturg peaks ka sel aastal jõudsalt kasvama / Violetta Riidas

    Riidas, Violetta

    2008-01-01

    Ilmunud ka: Äripäev 30. apr. lk. 16. Eelmise aasta ravimituru kasv jätkub tõenäoliselt ka sel aastal, kuna negatiivne riigieelarve ravimihüvitisi ei kärbi. Vt. samas: Võrdlus: Ravimituru jaotus haiglaapteekide ning teiste asutuste vahel peamiste ATC rühmade lõikes, 2007

  14. Potentiometric determination of acid dissociation constants (pKa) for human and veterinary antibiotics.

    Qiang, Zhimin; Adams, Craig

    2004-07-01

    This work determined the acid dissociation constants (pKa) of 26 common human and veterinary antibiotics by potentiometric titration. Selected antibiotics consisted of sulfonamides, macrolides, tetracyclines, fluoroquinolones, and other miscellaneous antibiotics. After validation of analysis methods using phosphoric acid as a model compound, a second-derivative (delta2pH/deltaV2) method was primarily applied to determining pKa's from titration curves for most antibiotics due to its convenience and accuracy. For tetracyclines, however, a least-square non-linear regression method was developed to determine their pKa's because the second-derivative method cannot well distinguish the pKa,2 and pKa,3 of tetracyclines. Results indicate that the pKa values are approximately 2 and 5-7.5 for sulfonamides; 7.5-9 for macrolides; 3-4, 7-8 and 9-10 for tetracyclines; 3-4, 6, 7.5-9 and 10-11 for fluoroquinolones; while compound-specific for other miscellaneous antibiotics. The moieties corresponding to specific pKa's were identified based on chemical structures of antibiotics. In addition, the pKa's available in literature determined by various techniques are compiled in comparison with the values of this work. These results are expected to essentially facilitate the research on occurrence, fate and effects, analysis methods development, and control of antibiotics in various treatment operations.

  15. Kõik, mis valesti sai minna, see on ka valesti läinud / George Soros

    Soros, George, 1930-

    2008-01-01

    Ilmunud ka: Molodjozh Estonii : Biznes Sreda, Delovõje Vedomosti 6. veebr. lk. 10. Praegune finantskriis, mille käivitas kinnisvaramulli lõhkemine USA-s, tähistab ka dollari kui rahvusvahelisel reservvaluutal baseeruva laenuandmise laienemise ajastu lõppu

  16. 18 Ka BP records of climatic changes, Bay of Bengal: Isotopic and sedimentological evidences

    Chauhan, O.S.; Suneethi, J.

    are also identified at 10.3 and 11.5 Ka BP. The later event matches well with that of the ‘Younger Dryas’ event of world climate models. The beginning of the Holocene is marked by lighter d18O values (at around 9.5 Ka BP), which has been interpreted...

  17. Determination of lactic acid bacteria in Kaºar cheese and ...

    Lactic acid bacteria (LAB) arise in Kaşar cheese, an artisanal pasta filata cheese produced in Turkey from raw milk without starter addition or pasteurized milk with starter culture. In this study, 13 samples of Kaşar cheese that were produced from raw milk were used as reference materials. LAB were characterized by using ...

  18. Ecotoxicology: Lead

    Scheuhammer, A.M.; Beyer, W.N.; Schmitt, C.J.; Jorgensen, Sven Erik; Fath, Brian D.

    2008-01-01

    Lead (Pb) is a naturally occurring metallic element; trace concentrations are found in all environmental media and in all living things. However, certain human activities, especially base metal mining and smelting; combustion of leaded gasoline; the use of Pb in hunting, target shooting, and recreational angling; the use of Pb-based paints; and the uncontrolled disposal of Pb-containing products such as old vehicle batteries and electronic devices have resulted in increased environmental levels of Pb, and have created risks for Pb exposure and toxicity in invertebrates, fish, and wildlife in some ecosystems.

  19. Ka Hana `Imi Na`auao: A Science Curriculum Project

    Napeahi, K.; Roberts, K. D.; Galloway, L. M.; Stodden, R. A.; Akuna, J.; Bruno, B.

    2005-12-01

    In antiquity, the first people to step foot on what are now known as the Hawaiian islands skillfully traversed the Pacific Ocean using celestial navigation and learned observations of scientific phenomena. Long before the Western world ventured beyond the horizon, Hawaiians had invented the chronometer, built aqueduct systems (awai) that continue to amaze modern engineers, and had preventive health systems as well as a comprehensive knowledge of medicinal plants (including antivirals) which only now are working their way through trials for use in modern pharmacopia. Yet, today, Native Hawaiians are severely underrepresented in science-related fields, reflecting (in part) a failure of the Western educational system to nurture the potential of these resourceful students, particularly the many "at-risk" students who are presently over-represented in special education. A curriculum which draws from and incorporates traditional Hawaiian values and knowledge is needed to reinforce links to the inquiry process which nurtured creative thinking during the renaissance of Polynesian history. The primary goal of the Ka Hana `Imi Na`auao Project (translation: `science` or `work in which you seek enlightenment, knowledge or wisdom`) is to increase the number of Native Hawaiian adults in science-related postsecondary education and employment fields. Working closely with Native Hawaiian cultural experts and our high school partners, we will develop and implement a culturally responsive 11th and 12th grade high school science curriculum, infused with math, literacy and technology readiness skills. Software and assistive technology will be used to adapt instruction to individual learners` reading levels, specific disabilities and learning styles. To ease the transition from secondary to post-secondary education, selected grade 12 students will participate in planned project activities that link high school experiences with college science-related programs of study. Ka Hana `Imi Na

  20. Calculation of attenuation by rain using the DAH model and diameter of antennas for the Ka Band in Mexico; Calculo de atenuacion por lluvia usando el modelo DAH y diametro de antena para Banda Ka en Mexico

    Landeros-Ayala, S.; Neri-Vela, R; Cruz-Sanchez, H.; Hernandez-Bautista, H. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    2002-03-01

    In the last years, the peak in the demand of satellite communication service has caused the saturation in the use of the frequencies corresponding to the band, Cand Ku. Due to this, the engineers have looked for viable alternatives, in order to satisfy the current requisition, as well as the future demand, for which a considerable increment is expected. One of these alternatives is the use of the Ka Band (20Hz/30Hz), that is why the importance of studying the propagation effects that are experienced at these frequencies, especially the attenuation effect by rain, as in this case, where it is significant. The present article has the purpose to describe the use of the Modelo DAH (whose authors are Asoka Dissanayake, Jeremy Allnutt and Fatim Haidara), mixed with the global maps of distribution of rain by Crane, for the calculation of the attenuation by rain in satellite communication systems operated in the Ka Band. Besides, antenna diameters for the systems of communications in Ka Band in different locations of the Mexican Republic, using for it the attenuation margins for rain obtained through the Modelo DAH, and using as references the characteristics of the ANIK F2 satellite and a terrestrial station VSAT, are proposed. [Spanish] En los ultimos anos, el auge en la demanda de servicios de comunicacion por satelite ha provocado la saturacion en los uso de la frecuencia correspondientes a las bandas C y Ku. Debido a esta razon, se han buscado alternativas viables para poder satisfacer la demanda actual, asi como la demanda futura, para la cual se espera un incremento considerable. Una de estas alternativas es el uso de Banda Ka (20Hz/30Hz), de ahi la importancia del estudio sobre los efectos de programacion que se experimentan a esta frecuencia, en especial, el efecto de atencion por lluvias, ya que sen este caso resulta ser significativa. El presente articulo tiene como finalidad describir el uso del Modelo DAH (cuyos autores son Asoka Dissanayake, Jeremy Allnutt y

  1. Leading men

    Bekker-Nielsen, Tønnes

    2016-01-01

    Through a systematic comparison of c. 50 careers leading to the koinarchate or high priesthood of Asia, Bithynia, Galatia, Lycia, Macedonia and coastal Pontus, as described in funeral or honorary inscriptions of individual koinarchs, it is possible to identify common denominators but also disting...

  2. A method of lines solution of the transient behavior of the helium cooled power leads for the SSC

    Demko, J.A.; Schiesser, W.E.; Carcagno, R.; McAshan, M.

    1995-01-01

    In this study, a detailed numerical thermal mode of a 6.5 kA power lead for the Superconducting Super Collider has been developed, which was adapted from the dynamic model developed by Schiesser. The transient behavior of the power leads was modeled using, a method of lines (MOL) approach. The model was developed to pmvide a tool for analyzing coolant control strategies as well as an understanding of the behavior of the leads under presumed system transients. Results for a current ramp up to 4970 amps are favorably compared with measurements. Also, a loss of cooling situation is predicted to determine the transient temperature distribution under an off-design condition

  3. Paleointensities on 8 ka obsidian from Mayor Island, New Zealand

    A. Ferk

    2011-11-01

    Full Text Available The 8 ka BP (6050 BCE pantelleritic obsidian flow on Mayor Island, Bay of Plenty, New Zealand, has been investigated using 30 samples from two sites. Due to a very high paramagnetic/ferromagnetic ratio, it was not possible to determine the remanence carriers. This is despite the fact that the samples were studied intensively at low, room, and high temperatures. We infer that a stable remanence within the samples is carried by single- or close to single-domain particles. Experiments to determine the anisotropy of thermoremanence tensor and the dependency on cooling rate were hampered due to alteration resulting from the repeated heating of the samples to temperatures just below the glass transition. Nonetheless, a well-defined mean paleointensity of 57.0 ± 1.0 μT, based on individual high quality paleointensity determinations, was obtained. This field value compares very well to a paleointensity of 58.1 ± 2.9 μT, which Tanaka et al. (2009 obtained for 5500 BCE at a site 100 km distant. Agreement with geomagnetic field models, however, is poor. Thus, gathering more high-quality paleointensity data for the Pacific region and for the southern hemisphere in general to better constrain global field models is very important.

  4. Design of Ka-band antipodal finline mixer and detector

    Yao Changfei; Xu Jinping; Chen Mo

    2009-01-01

    This paper mainly discusses the analysis and design of a finline single-ended mixer and detector. In the circuit, for the purpose of eliminating high-order resonant modes and improving transition loss, metallic via holes are implemented along the mounting edge of the substrate embedded in the split-block of the WG-finline-microstrip transition. Meanwhile, a Ka band slow-wave and bandstop filter, which represents a reactive termination, is designed for the utilization of idle frequencies and operation frequencies energy. Full-wave analysis is carried out to optimize the input matching network of the mixer and the detector circuit using lumped elements to model the nonlinear diode. The exported S-matrix of the optimized circuit is used for conversion loss and voltage sensitivity analysis. The lowest measured conversion loss is 3.52 dB at 32.2 GHz; the conversion loss is flat and less than 5.68 dB in the frequency band of 29-34 GHz. The highest measured zero-bias voltage sensitivity is 1450 mV/mW at 38.6 GHz, and the sensitivity is better than 1000 mV/mW in the frequency band of 38-40 GHz.

  5. Rain Fade Compensation for Ka-Band Communications Satellites

    Mitchell, W. Carl; Nguyen, Lan; Dissanayake, Asoka; Markey, Brian; Le, Anh

    1997-01-01

    This report provides a review and evaluation of rain fade measurement and compensation techniques for Ka-band satellite systems. This report includes a description of and cost estimates for performing three rain fade measurement and compensation experiments. The first experiment deals with rain fade measurement techniques while the second one covers the rain fade compensation techniques. The third experiment addresses a feedback flow control technique for the ABR service (for ATM-based traffic). The following conclusions were observed in this report; a sufficient system signal margin should be allocated for all carriers in a network, that is a fixed clear-sky margin should be typically in the range of 4-5 dB and should be more like 15 dB in the up link for moderate and heavy rain zones; to obtain a higher system margin it is desirable to combine the uplink power control technique with the technique that implements the source information rate and FEC code rate changes resulting in a 4-5 dB increase in the dynamic part of the system margin. The experiments would assess the feasibility of the fade measurements and compensation techniques, and ABR feedback control technique.

  6. DMPD: Interferon gene regulation: not all roads lead to Tolls. [Dynamic Macrophage Pathway CSML Database

    Full Text Available 16095970 Interferon gene regulation: not all roads lead to Tolls. Jefferies CA, Fit...zgerald KA. Trends Mol Med. 2005 Sep;11(9):403-11. (.png) (.svg) (.html) (.csml) Show Interferon gene regulation: not all roads... lead to Tolls. PubmedID 16095970 Title Interferon gene regulation: not all roads lead to

  7. Networking of Fruška Gora Lakes Tourist Offer through System of Cyclepaths – Case Study Sot, Bruje and Moharač (Serbia

    Aleksandra Vujko

    2011-01-01

    Full Text Available Fruška gora lakes Sot, Bruje and Moharač are the lakes that can be used in many ways for sports and recreation tourism. Nevertheless, the current tourism offer in these lakes is based only on offer for sports fishing. Bearing in mind that Fruška gora National Park, where there are three zones of protection, is of great importance the fact that the second and third zones are, with regard to territorial perspective, areas where it is desirable to develop sports and recreational tourism. Cycling is becoming an increasingly popular form of sports and recreational tourism, so tourism networking of Fruška gora lakes with system of cycle paths would represent only the first step to turn the whole mountain into the European cycle mainstream. In this sense, the aim of this paper is set to map the FJSA cycling paths connected to the system. The field research resulted in the mapping of the terrain. The interviews with experts from the Provincial Secretariat of Environmental Protection, the National Park and the Cycling Association of Vojvodina helped in the SWOT analysis of cycle tourism on Fruška gora lakes.

  8. Who Leads China's Leading Universities?

    Huang, Futao

    2017-01-01

    This study attempts to identify the major characteristics of two different groups of institutional leaders in China's leading universities. The study begins with a review of relevant literature and theory. Then, there is a brief introduction to the selection of party secretaries, deputy secretaries, presidents and vice presidents in leading…

  9. Studying NASA's Transition to Ka-Band Communications for Low Earth Orbit

    Chelmins, David T.; Reinhart, Richard C.; Mortensen, Dale; Welch, Bryan; Downey, Joseph; Evans, Michael

    2014-01-01

    As the S-band spectrum becomes crowded, future space missions will need to consider moving command and telemetry services to Ka-band. NASA's Space Communications and Navigation (SCaN) Testbed provides a software-defined radio (SDR) platform that is capable of supporting investigation of this service transition. The testbed contains two S-band SDRs and one Ka-band SDR. Over the past year, SCaN Testbed has demonstrated Ka-band communications capabilities with NASAs Tracking and Data Relay Satellite System (TDRSS) using both open- and closed-loop antenna tracking profiles. A number of technical areas need to be addressed for successful transition to Ka-band. The smaller antenna beamwidth at Ka-band increases the criticality of antenna pointing, necessitating closed loop tracking algorithms and new techniques for received power estimation. Additionally, the antenna pointing routines require enhanced knowledge of spacecraft position and attitude for initial acquisition, versus an S-band antenna. Ka-band provides a number of technical advantages for bulk data transfer. Unlike at S-band, a larger bandwidth may be available for space missions, allowing increased data rates. The potential for high rate data transfer can also be extended for direct-to-ground links through use of variable or adaptive coding and modulation. Specific examples of Ka-band research from SCaN Testbeds first year of operation will be cited, such as communications link performance with TDRSS, and the effects of truss flexure on antenna pointing.

  10. The Potential for a Ka-band (32 GHz) Worldwide VLBI Network

    Jacobs, C. S.; Bach, U.; Colomer, F.; Garcia-Miro, C.; Gomez-Gonzalez, J.; Gulyaev, S.; Horiuchi, S.; Ichikawa, R.; Kraus, A.; Kronschnabl, G.; hide

    2012-01-01

    Ka-band (32 GHz, 9mm) Very Long Baseline Interferometric (VLBI) networking has now begun and has tremendous potential for expansion over the next few years. Ka-band VLBI astrometry from NASA's Deep Space Network has already developed a catalog of 470 observable sources with highly accurate positions. Now, several antennas worldwide are planning or are considering adding Ka-band VLBI capability. Thus, there is now an opportunity to create a worldwide Ka-band network with potential for high resolution imaging and astrometry. With baselines approaching a Giga-lambda, a Ka-band network would be able to probe source structure at the nano-radian (200 as) level ( 100X better than Hubble) and thus gain insight into the astrophysics of the most compact regions of emission in active galactic nuclei. We discuss the advantages of Ka-band, show the known sources and candidates, simulate projected baseline (uv) coverage, and discuss potential radio frequency feeds. The combination of these elements demonstrates the feasibility of a worldwide Ka network within the next few years!

  11. Historical review of bryological research in Fruška Gora Mt. (Serbia

    Ilić Miloš M.

    2016-01-01

    Full Text Available Fruška Gora is a mountain located in the southern part of Pannonian plane and it is poorly bryologicaly investigated as well as most parts of Serbia. First data on bryophytes, for this region, were published in 1949 by Teodor Soška in his paper Pregled mahovina i lišajeva u okolini Beograda (Review of mosses and lichens in the vicinity of Belgrade. Soška listed 34 species of mosses and 8 liverworts species for this region. Later, in 1955, Zlatko Pavletić in his capital work Prodromus flore briofita Jugoslavije (Prodromus of Yugoslavian bryophyte flora, stated 26 moss species and 3 liverwort species, without indicating specific localities, but all of them were Soška’s original results. In 1966, the second botanist with original findings of bryophytes on Fruška Gora was Popović, who recorded 2 liverwort and 19 moss species, for this mountain, also without specific localities. By far, the most comprehensive data were given by Cvetić and Sabovljević in 2004. Their study A contribution to the bryophyte flora of Fruška Gora (Vojvodina, Serbia counted total number of 118 mosses and 14 liverworts, on 16 localities within National park Fruška Gora. The latest study on bryophytes of Fruška Gora was in 2013, and it is the first and so far, the last study of bryophyte assemblages on grasslands. Authors of this paper recorded 18 species of mosses from 29 releveé. Complete bryophyte flora of Fruška Gora is still unknown. Considering the fact that this is the region with high biodiversity, dense hydrological network and a rather complex geology, Fruška Gora certainly deserves further bryological researches.

  12. Enhanced Leads and Appointment System

    Social Security Administration — The data asset contains information on current or upcoming appointments, individuals who will be attending the appointment, potential intent to file a claim (lead),...

  13. Experience of superconducting current feeders system of SST-1

    Gupta, N.C.; Garg, A.; Sonara, D.

    2014-01-01

    The superconducting current feeder system for SST-1 which has been installed and commissioned recently along with SST-1, felicitates to energize the SST-1. The CFS consists of ten pairs of 10,000 Ampere (A) rating helium vapor cooled conventional current leads, interconnecting Cu-SC joints, three numbers of cryo-compatible SC feeders ducts, current leads assembly chamber, hydraulic network and three numbers of joint boxes operated at different current rating to charge Toroidal Field and Poloidal Field coils separately. During the last three campaigns, it was possible to achieve a controlled cool down up to 4 K and showed its rated operational performance. Actively cooled liquid nitrogen shield showed temperature profile in the temperature range of 80-85K and the whole system was evacuated up to 6x10 -6 mbar. The measured LHe consumption rates from TF VCCL were 0.3 g/s and 0.35 g/s at zero current and 1 kA respectively. (author)

  14. A ˜50 ka record of monsoonal variability in the Darjeeling foothill region, eastern Himalayas

    Ghosh, Ruby; Bera, Subir; Sarkar, Anindya; Paruya, Dipak Kumar; Yao, Yi-Feng; Li, Cheng-Sen

    2015-04-01

    Pollen, phytoliths and δ 13C signatures of soil organic matter from two fluvial sedimentary sequences of the Darjeeling foothill region, eastern Himalayas are used to portray palaeoclimatic oscillations and their impact on regional plant communities over the last ˜50 ka. Quantitative palaeoclimate estimation using coexistence approach on pollen data and other proxies indicate significant oscillations in precipitation during the late part of MIS 3 (46.4-25.9 ka), early and middle part of MIS 2 (25.9-15.6 ka), and 5.4 to 3.5 ka. Middle to late MIS 3 (ca 46.4-31 ka.) was characterized by a comparatively low monsoonal activity and slightly higher temperature than that during ca 31 ka onwards. Simultaneous expansion of deciduous trees and chloridoid grasses also imply a drier and warmer phase. Between 31 and 22.3 ka (late MIS 3 to mid-MIS 2), higher precipitation and a slightly cooler temperature led to an increase in evergreen elements over deciduous taxa and wet-loving panicoid grasses over dry-loving chloridoid grasses than earlier. After ca 22.3 ka, shrinking of forest cover, expansion of C4 chloridoid grasses, Asteraceae and Cheno-ams in the vegetation with lowering of temperature and precipitation characterized the onset of the LGM which continued till 18.3 ka. End of the LGM is manifested by a restoration in the forest cover and in the temperature and precipitation regime. Later, during 5.4 to 4.3 ka, a strong monsoonal activity supported a dense moist evergreen forest cover that subsequently declined during 4.3 to 3.5 ka. A further increase in deciduous elements and non-arboreals might be a consequence of reduced precipitation and higher temperature during this phase. A comparison between monsoonal rainfall, MAT and palaeoatmospheric CO2 with floral dynamics since last ˜50 ka indicates that these fluctuations in plant succession were mainly driven by monsoonal variations.

  15. Effect of methylation on the side-chain pKa value of arginine.

    Evich, Marina; Stroeva, Ekaterina; Zheng, Yujun George; Germann, Markus W

    2016-02-01

    Arginine methylation is important in biological systems. Recent studies link the deregulation of protein arginine methyltransferases with certain cancers. To assess the impact of methylation on interaction with other biomolecules, the pKa values of methylated arginine variants were determined using NMR data. The pKa values of monomethylated, symmetrically dimethylated, and asymmetrically dimethylated arginine are similar to the unmodified arginine (14.2 ± 0.4). Although the pKa value has not been significantly affected by methylation, consequences of methylation include changes in charge distribution and steric effects, suggesting alternative mechanisms for recognition. © 2015 The Protein Society.

  16. A Novel Ku-Band/Ka-Band and Ka-Band/E-Band Multimode Waveguide Couplers for Power Measurement of Traveling-Wave Tube Amplifier Harmonic Frequencies

    Wintucky, Edwin G.; Simons, Rainee N.

    2015-01-01

    This paper presents the design, fabrication and test results for a novel waveguide multimode directional coupler (MDC). The coupler, fabricated from two dissimilar frequency band waveguides, is capable of isolating power at the second harmonic frequency from the fundamental power at the output port of a traveling-wave tube (TWT) amplifier. Test results from proof-of-concept demonstrations are presented for a Ku-band/Ka-band MDC and a Ka-band/E-band MDC. In addition to power measurements at harmonic frequencies, a potential application of the MDC is in the design of a satellite borne beacon source for atmospheric propagation studies at millimeter-wave (mm-wave) frequencies (Ka-band and E-band).

  17. Assessment of protocols in cone beam CT with symmetric and asymmetric beam using effective dose and P{sub ka}

    Batista, W. O.; Linhares de O, M. V. [Instituto Federal da Bahia, Rua Emidio dos Santos s/n, Barbalho, Salvador, 40301015 Bahia (Brazil); Soares, M. R.; Maia, A. F. [Universidade Federal de Sergipe, Departamento de Fisica, Cidade Universitaria Prof. Jose Aloisio de Campos, Marechal Rondon s/n, Jardim Rosa Elze, 49-100000 Sao Cristovao, Sergipe (Brazil); Caldas, L. V. E., E-mail: wilsonottobatista@gmail.com [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2014-08-15

    The cone beam CT is an emerging technology in dental radiology with significant differences the point of view of design technology between the various manufacturers on the world market. This study aims to evaluate and compare protocols with similar purposes in a cone beam CT scanner using TLDs and air kerma - area product (P{sub ka}) as kerma index. Measurements were performed on two protocols used to obtain the image the maxilla-mandible in equipment Gendex GXCB 500: Protocol [GX1] extended diameter and asymmetric beam (14 cm x 8.5 cm - maxilla / mandible) and protocol [GX2] symmetrical beam (8.5 cm x 8.5 cm - maxillary / mandible). Was used LiF dosimeters (TLD 100) inserted into a female anthropomorphic phantom manufactured by Radiology Support Devices. For all protocols evaluated the value of P{sub ka} using a meter Diamentor E2 and PTW system Radcal Rapidose. The results obtained for Effective Dose / P{sub ka} these measurements were separated by protocol image. Protocol [GX1]: 44.5 μSv/478 mGy cm{sup 2}; protocol [GX2]: 54.8 μSv/507 mGy cm{sup 2}. These values indicate that the relationship between the diameter of the image acquired in the protocol [GX1] and the diameter of the image in the protocol [GX2] is equal to 1.65, the Effective Dose for the first protocol has lower value at 18%. P{sub ka} values reveal very similar results between the two protocols, although, common sense leads to the interpretation that imaging protocols with field of view (Fov) of large diameters imply high values of effective dose when compared to small diameters. However, in this particular case, this is not true due to the asymmetrical beam technology. Conclude that for the cases where the scanner uses asymmetric beam to obtain images with large diameters that cover the entire face there are advantages from the point of view of reducing the exposure of patients with respect to the use of symmetrical beam and / or to Fov images with a smaller diameter. (Author)

  18. Current limiters

    Loescher, D.H. [Sandia National Labs., Albuquerque, NM (United States). Systems Surety Assessment Dept.; Noren, K. [Univ. of Idaho, Moscow, ID (United States). Dept. of Electrical Engineering

    1996-09-01

    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  19. Uusim tehnika annab säästu ka maasoojuspumpades / Lauri Lehtinen

    Lehtinen, Lauri

    2009-01-01

    Õhksoojuspumpadega tuntust kogunud inverter- ehk sagedusmuunduriga kompressortehnikat kasutatakse ka uue põlvkonna maasoojuspumpades. Tootjate sõnul annab invertertehnika varasemate seadmetega võrreldes umbes 10–15% kokkuhoidu

  20. NOAA Ship Ka'imimoana Underway Meteorological Data, Near Real Time

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ka'imimoana Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  1. Ka-Band Electronically Steered CubeSat Antenna, Phase II

    National Aeronautics and Space Administration — Kymeta Government Solutions (KGS) designed, analyzed, built, tested, and delivered a small, lightweight, low-cost, low-power electronically steered Ka-band prototype...

  2. Solid State KA-Band, Solid State W-Band and TWT Amplifiers, Phase I

    National Aeronautics and Space Administration — Phase I of the proposal describes plans to develop a state of the art transmitter for the W-Band and KA -Band Cloud Radar system. Our focus will be concentrated in...

  3. CIA võis lennutada ja hoida vange ka Euroopa idaosas / Kaivo Kopli

    Kopli, Kaivo

    2006-01-01

    Amnesty Internationali raportis antakse ülevaade kolme vahistatud Jeemeni mehe kogetust aastatel 2003-2005. Meeste tunnistustest järeldab Amnesty, et neid hoiti kinni ka Ida-Euroopas. Lisa: Kolme Jeemeni mehe tunnistused

  4. Venezia filmifestivali punane vaip ootab tänavu ka eestlasi / Tiit Tuumalu

    Tuumalu, Tiit, 1971-

    2007-01-01

    Eesti mängufilm "Sügisball" (režissöör Veiko Õunpuu, produtsent Katrin Kissa) esilinastub 7. septembril Venezia 64. filmifestivali konkursiprogrammis Orizzonti. Ka teistest võistlevatest filmidest

  5. MMIC for High-Efficiency Ka-BAnd GaN Power Amplifiers (2007043), Phase I

    National Aeronautics and Space Administration — This proposal addresses the need for high-efficiency, high-output power amplifiers operating in the Ka-band frequencies. For space communications, the power...

  6. Tänane heategevuskontsert toetab ka Kiigemetsa kooli / Vaike Käosaar

    Käosaar, Vaike

    2007-01-01

    Heategevuskontserdist "Ma olen eriline" Põltsamaa lossihoovis, kus esinevad mitmed Eestimaa tuntud muusikud ja mille tulusid kasutatakse samasuguse pealkirjaga raamatu kirjastamise toetuseks, et aidata peresid, kus kasvab autistlikke lapsi ning Kiigemetsa Kooli, kus õpetatakse teiste seas ka autismipuudega lapsi

  7. Computational chemical analysis of unconjugated bilirubin anions and insights into pKa values clarification

    Vega-Hissi, Esteban G.; Estrada, Mario R.; Lavecchia, Martín J.; Pis Diez, Reinaldo

    2013-01-01

    The pKa, the negative logarithm of the acid dissociation equilibrium constant, of the carboxylic acid groups of unconjugated bilirubin in water is a discussed issue because there are quite different experimental values reported. Using quantum mechanical calculations we have studied the conformational behavior of unconjugated bilirubin species (in gas phase and in solution modeled implicitly and explicitly) to provide evidence that may clarify pKa values because of its pathophysiological relevance. Our results show that rotation of carboxylate group, which is not restricted, settles it in a suitable place to establish stronger interactions that stabilizes the monoanion and the dianion to be properly solvated, demonstrating that the rationalization used to justify the high pKa values of unconjugated bilirubin is inappropriate. Furthermore, low unconjugated bilirubin (UCB) pKa values were estimated from a linear regression analysis.

  8. Prediction Of pKa From Chemical Structure Using Free And Open-Source Tools

    The ionization state of a chemical, reflected in pKa values, affects lipophilicity, solubility, protein binding and the ability of a chemical to cross the plasma membrane. These properties govern the pharmacokinetic parameters such as absorption, distribution, metabolism, excreti...

  9. AHP 44: BILINGUAL EDUCATION IN AMDO - A CASE STUDY OF KHRI KA NATIONALITIES BOARDING SCHOOL

    Tshe dpal rdo rje ཚེ་དཔལ་རྡོ་རྗེ། (Caihuan Duojie 才还多杰

    2017-02-01

    Full Text Available The state sponsored education of Tibetan children in Khri ka (Guide County, Mtsho lho (Hainan Tibetan Autonomous Prefecture, Mtsho sngon (Qinghai Province, China, using Khri ka Nationalities Boarding School as a case study, is described. School history, the government rationale for closing village-based Tibetan primary schools, and the nationalities boarding schools operating in Khri ka in 2015 are introduced. Detailed descriptions of teachers; students; instructional materials; classes; language use; rules; punishments; home visiting; communication between students, parents, and teachers; school reports to the local authorities; and official local supervision and evaluation of Khri ka Nationalities Boarding School are also provided. An overall evaluation of this school concludes the paper.

  10. Determination of the pKa of Benzophenones in Ethanol-Water

    G. T. Castro

    2000-03-01

    Full Text Available The pKa of monohydroxylated benzophenones was determined by UV spectroscopy. The values obtained are coherent with the resonant forms and hydrogen bond intramolecular of the analyzed compounds.

  11. Riik plaanib haiglatele anda õiguse ka arstirohtu müüa / Andrus Karnau

    Karnau, Andrus

    2006-01-01

    Vt. ka Postimees : na russkom jazõke 31. märts lk. 3. Riik tahab anda haiglatele õiguse pidada jaemüügirohupoode, selle kava vastu on aga konkureerivad apteegiketid, konkurentsi- ja ravimiamet. Lisa: Ketistunud apteegiturg

  12. Potential for Paragliding Tourism Development in Niška Banja (South Serbia

    Lazar Pavić

    2013-07-01

    Full Text Available People today pay attention more on their health and because of that sports tourism becomes more popular. Especially popular segment of sports tourism is adventure sports including paragliding which has a special place. Tourist product of Niška Banja, as one of more visited tourism destination in Serbia, is mostly based on its health function. In the first part of this paper it is presented touristic valorisation of Niška Banja using criteria recommended form World Tourism Organization. In the second part of this paper it is used marketing mix as a tool for creating potential tourism product Paragliding weekend in Niška Banja. The aim of this paper is to show how the tourism offers of Niška Banja can be diversified using a new integrated product and how the touristic value can be increased.

  13. Gas cooled leads

    Shutt, R.P.; Rehak, M.L.; Hornik, K.E.

    1993-01-01

    The intent of this paper is to cover as completely as possible and in sufficient detail the topics relevant to lead design. The first part identifies the problems associated with lead design, states the mathematical formulation, and shows the results of numerical and analytical solutions. The second part presents the results of a parametric study whose object is to determine the best choice for cooling method, material, and geometry. These findings axe applied in a third part to the design of high-current leads whose end temperatures are determined from the surrounding equipment. It is found that cooling method or improved heat transfer are not critical once good heat exchange is established. The range 5 5 but extends over a large of values. Mass flow needed to prevent thermal runaway varies linearly with current above a given threshold. Below that value, the mass flow is constant with current. Transient analysis shows no evidence of hysteresis. If cooling is interrupted, the mass flow needed to restore the lead to its initially cooled state grows exponentially with the time that the lead was left without cooling

  14. High current and high power superconducting rectifiers

    Kate, H.H.J. ten; Bunk, P.B.; Klundert, L.J.M. van de; Britton, R.B.

    1981-01-01

    Results on three experimental superconducting rectifiers are reported. Two of them are 1 kA low frequency flux pumps, one thermally and magnetically switched. The third is a low-current high-frequency magnetically switched rectifier which can use the mains directly. (author)

  15. The 12 kV, 50 kA Pulse Generator for the SPS MKDH Horizontal Beam Dump Kicker System,equipped with Semiconductor Switches

    Bonthond, J; Faure, P; Vossenberg, Eugène B; CERN. Geneva. SPS and LHC Division

    2001-01-01

    The high current pulses for the MKDH magnets are generated with capacitor discharge type generators which, combined with a resistive free-wheel diode circuit, deliver a critically damped half-sine current with a rise-time of 25 ms. Each generator consists of two 25 kA units, connected in parallel to a magnet via low inductance transmission lines. They are equipped with a stack of four Fast High Current Thyristors, together with snubber capacitors, a voltage divider and a specially designed trigger transformer.

  16. Vesnička tesařů Ostrovec (Johannesdörfl)

    Vlček, Pavel

    6/7, 2016/2017 (2017), s. 39-46 ISSN 1805-8906 R&D Projects: GA MK DG16P02H023 Keywords : Ostrovec (Johannesdörfl) * carpenters * church od St. John the Baptist * František Maxmilián Kaňka * Johann Mathes Spiess * Anton Haffenecker Subject RIV: AL - Art, Architecture, Cultural Heritage OBOR OECD: Architectural design

  17. Design of a 2 kA, 30 fs Rf-Photoinjector for Waterbag Compression

    van der Geer, S. B.; Luiten, O. J.; de Loos, M. J.

    Because uniformly filled ellipsoidal ‘waterbag’ bunches have linear self-fields in all dimensions, they do not suffer from space-charge induced brightness degradation. This in turn allows very efficient longitudinal compression of high-brightness bunches at sub or mildly relativistic energies, a parameter regime inaccessible up to now due to detrimental effects of non-linear space-charge forces. To demonstrate the feasibility of this approach, we investigate ballistic bunching of 1 MeV, 100 pC waterbag electron bunches, created in a half-cell rf-photogun, by means of a two-cell booster-compressor. Detailed GPT simulations of this table-top set-up are presented, including realistic fields, 3D space-charge effects, path-length differences and image charges at the cathode. It is shown that with a single 10MW S-band klystron and fields of 100 MV/m, 2kA peak current is attainable with a pulse duration of only 30 fs at a transverse normalized emittance of 1.5 μm.

  18. submitter Performance Test of an 8 kA @ 10-T 4.2-K ReBCO-CORC Cable

    Mulder, Tim; Mentink, Matthias; van der Laan, Danko; Dhalle, Marc; ten Kate, Herman

    2016-01-01

    CERN is developing high-current ReBCO conductor on round core (CORC) cables for application in future detector and accelerator magnets. A characterization test on a ReBCO-CORC cable sample and its joints is performed in the 10-T FRESCA cable test facility at CERN. The sample is taken from the first 12-m-long CORC production. Key is the characterization of the field- and temperature-dependent critical currents of the CORC cable at 1.9 K and 4.2 K. Secondary objectives include evaluating the response of the CORC cable to quenches and the performance of cylindrical low resistive cable terminals especially designed and manufactured for use on CORC cables. The 7.6-mm CORC cable features 8 kA at 4.2 K and 10 T, and the joint terminals show a 25 ± 5 - nΩ resistance for 20-cm length.

  19. Determination of pKa values of new phenacyl-piperidine derivatives by potentiometric titration method in aqueous medium at room temperature (25±0.5oC).

    Zafar, Shaista; Akhtar, Shamim; Tariq, Talat; Mushtaq, Noushin; Akram, Arfa; Ahmed, Ahsaan; Arif, Muhammad; Naeem, Sabahat; Anwar, Sana

    2014-07-01

    Dissociation constant (pKa) of ten novel phenacyl derivatives of piperidine were determined by potentiometric titration method in aqueous medium at room temperature (25 ±0.5°C). The sample solutions were prepared in deionized water with ionic strength 0.01M and titrated with 0.1M NaOH solution. In addition, ΔG values were also calculated. Different prediction software programs were used to calculate pKa values too and compared to the experimentally observed pKa values. The experimental and theoretical values were found in close agreement. The results obtained in this research would help to predict the good absorption of the studied compounds and can be selected as lead molecules for the synthesis of CNS active agents because of their lipophilic nature especially compound VII.

  20. Improving Cry8Ka toxin activity towards the cotton boll weevil (Anthonomus grandis).

    Oliveira, Gustavo R; Silva, Maria C M; Lucena, Wagner A; Nakasu, Erich Y T; Firmino, Alexandre A P; Beneventi, Magda A; Souza, Djair S L; Gomes, José E; de Souza, José D A; Rigden, Daniel J; Ramos, Hudson B; Soccol, Carlos R; Grossi-de-Sa, Maria F

    2011-09-09

    The cotton boll weevil (Anthonomus grandis) is a serious insect-pest in the Americas, particularly in Brazil. The use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. Therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. The present study focuses on the identification of novel molecules that show improved toxicity against the cotton boll weevil. In vitro directed molecular evolution through DNA shuffling and phage display screening was applied to enhance the insecticidal activity of variants of the Cry8Ka1 protein of Bacillus thuringiensis. Bioassays carried out with A. grandis larvae revealed that the LC50 of the screened mutant Cry8Ka5 toxin was 3.15-fold higher than the wild-type Cry8Ka1 toxin. Homology modelling of Cry8Ka1 and the Cry8Ka5 mutant suggested that both proteins retained the typical three-domain Cry family structure. The mutated residues were located mostly in loops and appeared unlikely to interfere with molecular stability. The improved toxicity of the Cry8Ka5 mutant obtained in this study will allow the generation of a transgenic cotton event with improved potential to control A. grandis.

  1. Improving Cry8Ka toxin activity towards the cotton boll weevil (Anthonomus grandis

    Gomes José E

    2011-09-01

    Full Text Available Abstract Background The cotton boll weevil (Anthonomus grandis is a serious insect-pest in the Americas, particularly in Brazil. The use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. Therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. The present study focuses on the identification of novel molecules that show improved toxicity against the cotton boll weevil. In vitro directed molecular evolution through DNA shuffling and phage display screening was applied to enhance the insecticidal activity of variants of the Cry8Ka1 protein of Bacillus thuringiensis. Results Bioassays carried out with A. grandis larvae revealed that the LC50 of the screened mutant Cry8Ka5 toxin was 3.15-fold higher than the wild-type Cry8Ka1 toxin. Homology modelling of Cry8Ka1 and the Cry8Ka5 mutant suggested that both proteins retained the typical three-domain Cry family structure. The mutated residues were located mostly in loops and appeared unlikely to interfere with molecular stability. Conclusions The improved toxicity of the Cry8Ka5 mutant obtained in this study will allow the generation of a transgenic cotton event with improved potential to control A. grandis.

  2. Computing pKa Values in Different Solvents by Electrostatic Transformation.

    Rossini, Emanuele; Netz, Roland R; Knapp, Ernst-Walter

    2016-07-12

    We introduce a method that requires only moderate computational effort to compute pKa values of small molecules in different solvents with an average accuracy of better than 0.7 pH units. With a known pKa value in one solvent, the electrostatic transform method computes the pKa value in any other solvent if the proton solvation energy is known in both considered solvents. To apply the electrostatic transform method to a molecule, the electrostatic solvation energies of the protonated and deprotonated molecular species are computed in the two considered solvents using a dielectric continuum to describe the solvent. This is demonstrated for 30 molecules belonging to 10 different molecular families by considering 77 measured pKa values in 4 different solvents: water, acetonitrile, dimethyl sulfoxide, and methanol. The electrostatic transform method can be applied to any other solvent if the proton solvation energy is known. It is exclusively based on physicochemical principles, not using any empirical fetch factors or explicit solvent molecules, to obtain agreement with measured pKa values and is therefore ready to be generalized to other solute molecules and solvents. From the computed pKa values, we obtained relative proton solvation energies, which agree very well with the proton solvation energies computed recently by ab initio methods, and used these energies in the present study.

  3. A Ka-Band Celestial Reference Frame with Applications to Deep Space Navigation

    Jacobs, Christopher S.; Clark, J. Eric; Garcia-Miro, Cristina; Horiuchi, Shinji; Sotuela, Ioana

    2011-01-01

    The Ka-band radio spectrum is now being used for a wide variety of applications. This paper highlights the use of Ka-band as a frequency for precise deep space navigation based on a set of reference beacons provided by extragalactic quasars which emit broadband noise at Ka-band. This quasar-based celestial reference frame is constructed using X/Ka-band (8.4/32 GHz) from fifty-five 24-hour sessions with the Deep Space Network antennas in California, Australia, and Spain. We report on observations which have detected 464 sources covering the full 24 hours of Right Ascension and declinations down to -45 deg. Comparison of this X/Ka-band frame to the international standard S/X-band (2.3/8.4 GHz) ICRF2 shows wRMS agreement of approximately 200 micro-arcsec in alpha cos(delta) and approximately 300 micro-arcsec in delta. There is evidence for systematic errors at the 100 micro-arcsec level. Known errors include limited SNR, lack of instrumental phase calibration, tropospheric refraction mis-modeling, and limited southern geometry. The motivation for extending the celestial reference frame to frequencies above 8 GHz is to access more compact source morphology for improved frame stability and to support spacecraft navigation for Ka-band based NASA missions.

  4. Installing the earth station of Ka-band satellite frequency in Malaysia: conceptual framework for site decision

    Mahmud, M. R.; Reba, M. N. M.; Jaw, S. W.; Arsyad, A.; Ibrahim, M. A. M.

    2017-05-01

    This paper developed a conceptual framework in determining the suitable location in installing the earth station for Ka-band satellite communication in Malaysia. This current evolution of high throughput satellites experienced major challenge due to Malaysian climate. Because Ka-band frequency is highly attenuated by the rainfall; it is an enormous challenge to define the most appropriate site for the static communication. Site diversity, a measure to anticipate this conflict by choosing less attenuated region and geographically change the transmission strategy on season basis require accurate spatio-temporal information on the geographical, environmental and hydro-climatology at local scale. Prior to that request, this study developed a conceptual framework to cater the needs. By using the digital spatial data, acquired from site measurement and remote sensing, the proposed framework applied a multiple criteria analysis to perform the tasks of site selection. With the advancement of high resolution remotely sensed data, site determination can be conducted as in Malaysia; accommodating a new, fast, and effective satellite communication. The output of this study is one of the pioneer contributions to create a high tech-society.

  5. Enhanced lower hybrid current drive experiments on HT-7 tokamak

    Shen Weici; Kuang Guangli; Liu Yuexiu; Ding Bojiang; Shi Yaojiang

    2003-01-01

    Effective Lower Hybrid Current Driving (LHCD) and improved confinement experiments in higher plasma parameters (I p >200 kA, n e >2 x 10 13 cm -3 , T e ≥1 keV) have been curried out in optimized LH wave spectrum and plasma parameters in HT-7 superconducting tokamak. The dependence of current driving efficiency on LH power spectrum, plasma density (anti n e ) and toroidal magnetic field B T has been obtained under optimal conditions. A good CD efficiency was obtained at higher plasma current and higher electron density. The improvement of the energy confinement time is accompanied with the increase in line averaged electron density, and in ion and electron temperatures. The highest current driving efficiency reached η CD =I p (anti n e )R/P RF ≅1.05 x 10 19 Am -2 /W. Wave-plasma coupling was sustained in a good state and the reflective coefficient was less than 5%. The experiments have also demonstrated the ability of LH wave in the start-up and ramp-up of the plasma current. The measurement of the temporal distribution of plasma parameter shows that lower hybrid leads to a broader profile in plasma parameter. The LH power deposition profile and the plasma current density profile were modeled with a 2D Fokker-Planck code corresponding to the evolution process of the hard x-ray detector array

  6. High Efficiency Traveling-Wave Tube Power Amplifier for Ka-Band Software Defined Radio on International Space Station-A Platform for Communications Technology Development

    Simons, Rainee N.; Force, Dale A.; Kacpura, Thomas J.

    2013-01-01

    The design, fabrication and RF performance of the output traveling-wave tube amplifier (TWTA) for a space based Ka-band software defined radio (SDR) is presented. The TWTA, the SDR and the supporting avionics are integrated to forms a testbed, which is currently located on an exterior truss of the International Space Station (ISS). The SDR in the testbed communicates at Ka-band frequencies through a high-gain antenna directed to NASA s Tracking and Data Relay Satellite System (TDRSS), which communicates to the ground station located at White Sands Complex. The application of the testbed is for demonstrating new waveforms and software designed to enhance data delivery from scientific spacecraft and, the waveforms and software can be upgraded and reconfigured from the ground. The construction and the salient features of the Ka-band SDR are discussed. The testbed is currently undergoing on-orbit checkout and commissioning and is expected to operate for 3 to 5 years in space.

  7. Quench properties of high current superconductors

    Garber, M; Sampson, W B

    1980-01-01

    A technique has been developed which allows the simultaneous determination of most of the important parameters of a high current superconductor. The critical current, propagation velocity, normal state resistivity, magnetoresistance, and enthalpy are determined as a function of current and applied field. The measurements are made on non-inductive samples which simulate conditions in full scale magnets. For wide, braided conductors the propagation velocity was found to vary approximately quadratically with current in the 2 to 5 kA region. A number of conductors have been tested including some Nb/sub 3/Sn braids which have critical currents in excess of 10 kA at 5 T, 4.2 K.

  8. Performance of the cold powered diodes and diode leads in the main magnets of the LHC

    Willering, G P; Bajko, M; Bednarek, M; Bottura, L; Charifoulline, Z; Dahlerup-Petersen, K; Dib, G; D'Angelo, G; Gharib, A; Grand-Clement, L; Izquierdo Bermudez, S; Prin, H; Roger, V; Rowan, S; Savary, F; Tock, J-Ph; Verweij, A

    2015-01-01

    During quench tests in 2011 variations in resistance of an order of magnitude were found in the diode by-pass circuit of the main LHC magnets. An investigation campaign was started to understand the source, the occurrence and the impact of the high resistances. Many tests were performed offline in the SM18 test facility with a focus on the contact resistance of the diode to heat sink contact and the diode wafer temperature. In 2014 the performance of the diodes and diode leads of the main dipole bypass systems in the LHC was assessed during a high current qualification test. In the test a current cycle similar to a magnet circuit discharge from 11 kA with a time constant of 100 s was performed. Resistances of up to 600 μΩ have been found in the diode leads at intermediate current, but in general the high resistances decrease at higher current levels and no sign of overheating of diodes has been seen and the bypass circuit passed the test. In this report the performance of the diodes and in particular the co...

  9. Molecular Paleoclimate Reconstructions over the Last 9 ka from a Peat Sequence in South China.

    Xinxin Wang

    Full Text Available To achieve a better understanding of Holocene climate change in the monsoon regions of China, we investigated the molecular distributions and carbon and hydrogen isotope compositions (δ13C and δD values of long-chain n-alkanes in a peat core from the Shiwangutian (SWGT peatland, south China over the last 9 ka. By comparisons with other climate records, we found that the δ13C values of the long-chain n-alkanes can be a proxy for humidity, while the δD values of the long-chain n-alkanes primarily recorded the moisture source δD signal during 9-1.8 ka BP and responded to the dry climate during 1.8-0.3 ka BP. Together with the average chain length (ACL and the carbon preference index (CPI data, the climate evolution over last 9 ka in the SWGT peatland can be divided into three stages. During the first stage (9-5 ka BP, the δ13C values were depleted and CPI and Paq values were low, while ACL values were high. They reveal a period of warm and wet climate, which is regarded as the Holocene optimum. The second stage (5-1.8 ka BP witnessed a shift to relatively cool and dry climate, as indicated by the more positive δ13C values and lower ACL values. During the third stage (1.8-0.3 ka BP, the δ13C, δD, CPI and Paq values showed marked increase and ACL values varied greatly, implying an abrupt change to cold and dry conditions. This climate pattern corresponds to the broad decline in Asian monsoon intensity through the latter part of the Holocene. Our results do not support a later Holocene optimum in south China as suggested by previous studies.

  10. Molecular Paleoclimate Reconstructions over the Last 9 ka from a Peat Sequence in South China

    Wang, Xinxin; Huang, Xianyu; Sachse, Dirk; Ding, Weihua; Xue, Jiantao

    2016-01-01

    To achieve a better understanding of Holocene climate change in the monsoon regions of China, we investigated the molecular distributions and carbon and hydrogen isotope compositions (δ13C and δD values) of long-chain n-alkanes in a peat core from the Shiwangutian (SWGT) peatland, south China over the last 9 ka. By comparisons with other climate records, we found that the δ13C values of the long-chain n-alkanes can be a proxy for humidity, while the δD values of the long-chain n-alkanes primarily recorded the moisture source δD signal during 9–1.8 ka BP and responded to the dry climate during 1.8–0.3 ka BP. Together with the average chain length (ACL) and the carbon preference index (CPI) data, the climate evolution over last 9 ka in the SWGT peatland can be divided into three stages. During the first stage (9–5 ka BP), the δ13C values were depleted and CPI and Paq values were low, while ACL values were high. They reveal a period of warm and wet climate, which is regarded as the Holocene optimum. The second stage (5–1.8 ka BP) witnessed a shift to relatively cool and dry climate, as indicated by the more positive δ13C values and lower ACL values. During the third stage (1.8–0.3 ka BP), the δ13C, δD, CPI and Paq values showed marked increase and ACL values varied greatly, implying an abrupt change to cold and dry conditions. This climate pattern corresponds to the broad decline in Asian monsoon intensity through the latter part of the Holocene. Our results do not support a later Holocene optimum in south China as suggested by previous studies. PMID:27505008

  11. Kanegelo ya Nimirode: Re lebelela diphihlelelo t�a gagwe ka lefsa

    Elelwani B. Farisani

    2011-03-01

    Full Text Available Kanegelo ya Hama/Nimirode e �omi�it�we go gatelela Bathobaso ba Afrika-Borwa le ba Amerika. Taodi�wana ye e lekola Nimirode ka lefsa le go t�ea magato a go bu�et�a seriti sa gagwe le sa Bathobaso sekeng.Seo se tlo dirwa ka dikgato t�e tlhano ka mo tlase. Sa mathomo, re tlo lekola dimelo t�a bana ba Noage, go kwe�i�a Nimirode, yo e lego yena �edi ye kgolo ya taodi�wana ye. Sa bobedi re tlo lebelela ka fao bangwadi ba bangwe ba t�welet�ago seswant�ho sa go befa sa Nimirode. Sa boraro, re tlo sekaseka tiri�o ya kanegelo ya Hama/Nimirode go gatelela le go dira Bathobaso makgoba. Sa bone, re tlo sekaseka diphihlelelo le dikatlego t�a Nimirode. Mo re tlo tsepelela diphihlelelo t�a gagwe t�e tharo t�e kgolo bjalo ka go ba mmu�i wa maemo, motsomi yo maatla le moagi. Nepo ya karolo ye ke go ganet�ana le tshekatsheko ya go se be botse ye e nepilwego Nimirode nakong ya go feta. Re tlo tlalelet�a ka go fa tshekatsheko ye e tebilego ya thogako godimo ga Hama/Ku�e/Nimirode. Sa bohlano, ebile e le sa mafelelo, re tlo t�welet�a nyanyeng bohlokwa bja kanegelo ya Nimirode go bao ba bego ba gatelet�we le go ba makgoba ka baka la temana ye. Re tlo nepi�a Afrika-Borwa.

  12. A 27 ka paleoenvironmental lake sediment record from Taro Co, central Tibetan Plateau: implications for the interplay between monsoon and the Westerlies

    Wang, J.; Ma, Q.; Huang, L.; Ju, J.; Guo, Y.; Lin, X.; Li, Y.; Zhu, L.

    2017-12-01

    The climate of Tibetan Plateau (TP) is mainly influenced by the Indian Ocean Summer Monsoon (IOSM) and the Westerlies. The interaction of these two air masses is therefore a crucial scientific issue to understand how they impact the climate in this area, especially in the geological times. However, constrained by the available archives, researches on this topic are still very few in the hinterland of the TP, especially covering the Last Glacial Maximum (LGM) period. Here we present a new lake sediment record retrieved from Taro Co covering the last 27 ka to elucidate how the IOSM and the Westerlies interact and the possible mechanisms. Taro Co (486 km2, Dmax: 132m, 4565 m a.s.l., currently closed), located on the central TP, is a fresh lake with the major supply from glaciers. Two parallel piston cores as well as several gravity cores were retrieved from the deepest parts. These cores were correlated based on high resolution XRF scanning and a continuous 1069 cm-long core was finally integrated. Chronology was determined by 210Pb, 137Cs and AMS 14C measurements. Multidiscipline analyses including grain size, total organic carbon (TOC), total nitrogen, diatom, ostracod, pollen and n-alkanes were accomplished to reconstruct paleoenvironmental changes. The lake level of Taro Co was low since 27 cal ka BP indicated by very coarse materials and diatom assemblages with gradually increased temperature and salinity (TOC and carbonate getting higher). The terrestrial water input decreased continuously reflected by such elements as Si, Ti, Fe, K. It is likely that there was a sedimentation gap between 961-954cm, corresponding to 23.4 to 18.6 cal ka BP probably demonstrated Taro Co was very shallow at that period. The first prominent abrupt change of most proxies was observed at 14.7 cal ka BP showing a great lake deepening which likely indicated an enhancement of IOSM. There were several spells with abrupt changes of cold/warm stages before the Holocene and the Younger Dryas

  13. 柴达木盆地大浪滩130ka BP以来的孢粉组合与古气候%Sporo-pollen assemblage and palaeoenvironment since 130 ka BP in Dalangtan Lake of Qaidarn Basin

    侯献华; 郑绵平; 杨振京; 杨庆华; 毕志伟

    2011-01-01

    southwest moist flow, which made the flora of Himalayan cedar grow in the mountainous area of the western Qaidam. Although the pollen study reveals the vegetation and environmental changes in the last interglacial period in the western Qaidam Basin which concentrated a great concern in the project of the global changes in the past (PAGES). But the lack of exposed pollen in the salt layer in the hole and pollen percentage and pollen collection rate in the area on current and past vegetation correction cannot be enough to expore the recent 130 thou. years of the process of vegetation and climate change and the formation mechanism in the western Qaidam, therefore, only when the more palynological evidence is obtained from the more boreholes which make accurate resolution of pollen data support related to the disciplines.%应用柴达盆地西部大浪滩梁ZK02孔岩芯,依据铀系年龄数据,选择130 ka BP(90.5 m以上)的含石膏粉砂淤泥层中34个样品进行孢粉分析研究,依据其孢粉组合特征,将该孔深90.5m以浅的孢粉百分比图式从下至上划分6个区域性孢粉带,进而分析了该区末次间冰期(130 ka BP)以来的古植被状况,结果表明,山地主要由松、云杉、冷杉等组成的寒温性针叶林覆盖,而盆地则主要是以蒿、菊、禾本科等中旱生草本植物组成的温性草原,总体上反映了该区130 ka以来代表冷干气候的5次成盐期及其所夹的6次温湿期变化韵律,由此可以推测,该区主要植被和古环境的进程很可能源于东亚夏季风的减弱或增强,其气候旋迴大致可以和青海湖QH-86孢粉分析所揭示的130 ka以来古植被演替及深海氧同位素第三阶段乃至黄土磁化率所反映的6个夏季风增强的时段进行对比.

  14. Development of plasma current waveform adjusting system ZLJ for tokamak device HL-1

    Wang Shangbing; Hu Haotian; Tang Fangqun; Zhou Yongzheng; Chu Xiuzhong; Cheng Jiashun; Gao Yunxia

    1989-12-01

    The control of some typical Tokamak discharge waveforms has been achieved by using plasma current waveform adjusting system ZLJ in the ohmic heating of HL-1. The discharge waveforms include a series of regular plasma current waveforms with various slow rising rate, such as 80 kA, 450 ms long flat-topping; 100 kA, 200 ms rising; 200 ms falt-topping and 180 kA, 400 ms slow rising etc. The design principle of the system and the initial experimental results are described

  15. A 5 kA pulsed power supply for inductive and plasma loads in large volume plasma device

    Srivastava, P. K., E-mail: pkumar@ipr.res.in; Singh, S. K.; Sanyasi, A. K.; Awasthi, L. M., E-mail: kushagra.lalit@gmail.com; Mattoo, S. K. [Institute for Plasma Research, Gandhinagar (India)

    2016-07-15

    This paper describes 5 kA, 12 ms pulsed power supply for inductive load of Electron Energy Filter (EEF) in large volume plasma device. The power supply is based upon the principle of rapid sourcing of energy from the capacitor bank (2.8 F/200 V) by using a static switch, comprising of ten Insulated Gate Bipolar Transistors (IGBTs). A suitable mechanism is developed to ensure equal sharing of current and uniform power distribution during the operation of these IGBTs. Safe commutation of power to the EEF is ensured by the proper optimization of its components and by the introduction of over voltage protection (>6 kV) using an indigenously designed snubber circuit. Various time sequences relevant to different actions of power supply, viz., pulse width control and repetition rate, are realized through optically isolated computer controlled interface.

  16. 3D stratigraphic modeling of the Congo turbidite system since 210 ka: an investigation of factors controlling sedimentation

    Laurent, Dimitri; Picot, Marie; Marsset, Tania; Droz, Laurence; Rabineau, Marina; Granjeon, Didier; Molliex, Stéphane

    2017-04-01

    intensity. These external forcing factors are responsible for the evolution of the capacity of turbidity currents by directly acting on the river runoff magnitude and the sediment budget according to the balance between mechanical and chemical erosion. If the sediment supply is the key parameter for the large scale sedimentary cycles, a steep increase of the sand/mud ratio leads to the development of sub-cycles characterized by middle fan avulsions. We identified these events as related to abrupt destabilizations of river mouth bars linked to periodic Congo River floods. Finally, the local slope gradient only plays a role in the maximal length of the turbidity currents and deposition in the most distal part of the basin. To conclude, the stratigraphic modeling allows us to propose an evolutionary "source to sink" model of the Quaternary Congo Fan, emphasizing the interconnection through time between drainage basin responses to climate change and sedimentary transfers in the deep-water environment. Picot, M. et al., 2016. Controls on turbidite sedimentation: Insights from a quantitative approach of submarine channel and lobe architecture (Late Quaternary Congo Fan). Marine and Petroleum Geology, 72, 423-446. Keywords: Congo, sedimentary basin, Quaternary, turbidite system, sedimentary cycles, geophysical data, stratigraphic modeling, DionisosFlow

  17. Diatom species composition in the Raška river (Southwestern Serbia

    Vidaković Danijela P.

    2015-01-01

    Full Text Available The paper presents data on the composition of epilithic diatoms in the Raška River. Samples were collected by scraping stone surfaces with a brush from 5 localities along the Raška River in April, June, August and November 2011 and March and May 2012. Diatom frustules were cleaned using cold acid method, and mounted on permanent slides. An investigation of the Raška River resulted in description of 106 diatom taxa. The most species rich genera are Navicula (10, Gomphonema (10 and Nitzschia (9, while other genera are presented with one or more species. Detailed floristic analysis of the benthic diatom flora in this river has not been conducted before. Therefore, this paper provides a groundwork for future researches. [Projekat Ministarstva nauke Republike Srbije, br. TR 037009

  18. Ka-band microwave generation using the Smith-Purcell effect

    Ekdahl, C.A.; Davis, H.A.

    1983-01-01

    The CERETRON microwave generator concept relies on the conversion of intense relativistic electron beam (REB) energy into highpower microwave emission through the Smith-Purcell effect. We report initial results from experiments with the production of Ka-band Smith-Purcell radiation generated by a 50-kA, 2.8-MeV beam propagated through a cylindrical transmission grating with lambda 0 = 1 cm. These experiments were performed without a quasi-optical resonator, and the output was limited by breakdown of the grating and by limited access through the 90-kG magnet coil. Nevertheless, the measured power output from these initial experiments was about 7 kW in the Ka band

  19. Validation of SARAL/AltiKa data in the Amazon basin

    Santos da Silva, Joecila; Calmant, Stephane; Medeiros Moreira, Daniel; Oliveira, Robson; Conchy, Taina; Gennero, Marie-Claude; Seyler, Frederique

    2015-04-01

    SARAL/AltiKa is a link between past missions (since it flies on the ERS-ENVISAT orbit with Ku band nadir altimeters in LRM) and future missions such as SWOT's Ka band interferometry swaths. In the present study, we compare the capability of its altimeter AltiKa to that of previous missions working in the Ku band such as ENVISAT and Jason-2 in retrieving water levels over the Amazon basin. Same as for the aforementioned preceding missions, the best results were obtained with the ICE-1 retracking algorithm. We qualitatively analyze the impact of rainfalls in the loss of measurements. Since making long -multi mission- time series is of major importance either for hydro-climatic studies or for basin management, we also present an estimate of the altimeter bias in order that the SARAL series of water level can be appended to those of these previous missions.

  20. pKa values in proteins determined by electrostatics applied to molecular dynamics trajectories.

    Meyer, Tim; Knapp, Ernst-Walter

    2015-06-09

    For a benchmark set of 194 measured pKa values in 13 proteins, electrostatic energy computations are performed in which pKa values are computed by solving the Poisson-Boltzmann equation. In contrast to the previous approach of Karlsberg(+) (KB(+)) that essentially used protein crystal structures with variations in their side chain conformations, the present approach (KB2(+)MD) uses protein conformations from four molecular dynamics (MD) simulations of 10 ns each. These MD simulations are performed with different specific but fixed protonation patterns, selected to sample the conformational space for the different protonation patterns faithfully. The root-mean-square deviation between computed and measured pKa values (pKa RMSD) is shown to be reduced from 1.17 pH units using KB(+) to 0.96 pH units using KB2(+)MD. The pKa RMSD can be further reduced to 0.79 pH units, if each conformation is energy-minimized with a dielectric constant of εmin = 4 prior to calculating the electrostatic energy. The electrostatic energy expressions upon which the computations are based have been reformulated such that they do not involve terms that mix protein and solvent environment contributions and no thermodynamic cycle is needed. As a consequence, conformations of the titratable residues can be treated independently in the protein and solvent environments. In addition, the energy terms used here avoid the so-called intrinsic pKa and can therefore be interpreted without reference to arbitrary protonation states and conformations.

  1. Analysis of Cry8Ka5-binding proteins from Anthonomus grandis (Coleoptera: Curculionidae) midgut.

    Nakasu, Erich Y T; Firmino, Alexandre A P; Dias, Simoni C; Rocha, Thales L; Ramos, Hudson B; Oliveira, Gustavo R; Lucena, Wagner; Carlini, Célia R; Grossi-de-Sá, Maria Fátima

    2010-07-01

    Biotech crops expressing Bacillus thuringiensis Cry toxins present a valuable approach for insect control. Cry8Ka5, which is highly toxic to the cotton boll weevil (Anthonomus grandis), was used as a model to study toxin-ligand interactions. Three Cry-binding proteins were detected after toxin overlay assays. Following de novo sequencing, a heat-shock cognate protein and a V-ATPase were identified, whilst a approximately 120 kDa protein remained unknown. Additional Cry8Ka5-binding proteins were visualized by two-dimensional gel electrophoresis ligand blots. (c) 2010 Elsevier Inc. All rights reserved.

  2. Thermal Runaway of the 13 kA Busbar Joints in the LHC

    Verweij, A P

    2010-01-01

    Triggered by the incident in the LHC in September 2008, the thermo-electrical stability of the 10,000 soldered busbar joints in the 13 kA circuits of the LHC has been re-assessed. For this purpose the computer model QP3 has been developed. In this paper the results of some calculations are presented, and it is shown how the results have been used to improve the quench detection system and ensure safe future operation. First the layout of the 13 kA circuits, the geometry of the soldered joints...

  3. MARIJANSKA PUČKA BLAGDANSKA IMENA NA DUBROVAČKOM PODRUČJU

    Vulić, Sanja

    2009-01-01

    U radu se opisuju pučka imena blagdana Gospe Karmelske, Gospe od Anđela, Gospina Pohoda sv. Elizabeti, Gospe od Krunice, Gospe Snježne, Gospe od Zdravlja, Gospe Lurdske, Gospe Fatimske, Imena Marijina, Gospe od Sedam Žalosti, Bezgrješnoga Začeća, Velike Gospe, Male Gospe i nekih lokalnih svetkovina. Uglavnom se razmatraju pučka blagdanska imena koja sam prikupila osobnim terenskim istraživanjem u samom gradu Dubrovniku, u Postranju u Župi dubrovačkoj, u Trpnju i Orebiću na Pelješcu te na otok...

  4. Kas kollaste kaartide lõpp toob lõpu ka lapsesoodustusele? / Jarno Laur

    Laur, Jarno, 1975-

    2006-01-01

    Erastamisväärtpaberite väljaandmise ja kasutamise lõpetamise eelnõust, millega lõpetataks ka lastega seotud 25 000 kroonine hinnasoodustus maa väljaostmisel. Sama ka Vali Uudised 13. jaan. 2005, lk. 2 ; Kuulutaja 13. jaan. 2006, lk. 4 ; Põhjarannik 13. jaan. 2006, lk. 2 ; Lääne Elu 17. jaan. 2006, lk. 2 ; Nädaline 17. jaan. 2006, lk. 2 ; Hiiu Leht 17. jaan. 2006, lk. 2 ; Lõunaleht 19. jaan. 2006, lk. 2 ; Meie Maa 17. jaan. 2006, lk. 2 ; Vooremaa 21. jaan. 2006, lk. 2 ; Virumaa Nädalaleht 13. jaan. 2006, lk. 2 ; Valgamaalane 19. jaan. 2006, lk. 2

  5. Socialization as a factor of influence on the satisfaction of participants of the Fruška gora mountaineering marathon

    Marković Jelica

    2015-01-01

    Full Text Available Customer satisfaction is a guarantee of success in all fields, including those related to the organization of sport events. As a consequence of the event quality appears visitor satisfaction which significantly impacts on the their loyalty and 'word of mouth' promotion, so examination of these categories is especially important to the event organizers in order to control and improve the event. Sports events can be viewed in a broader context, where it is not of primary importance reaching the sports results, but is more emphasized its non-competitive nature. In this case, the sport events include recreation, relaxation, entertainment and leisure, with a significantly different approach and intentions of the organization. Such events lead to intercultural exchange, increase the level of socialization and promote physical activity as a function of improving health. Having in mind that it assumed the characteristics of mass and has become an influential factor in the Vojvodina tourism, this study aims to analyze the quality of the Mountaineering marathon on Fruška gora from the perspective of the participants' satisfaction. For collecting the data, it was used the questionnaire. The sample included 134 participants of the 35th Mountaineering marathon on Fruška gora. For measuring this event quality, it was used modified model SEQSS with 4 dimensions: quality of marathon program, quality of interaction, quality of outcomes and quality of the physical environment. The results have shown that the quality of all measured dimensions is at a high level and that measuring dimension the quality outcome, which includes the socialization and valence, has the greatest impact on the satisfaction of the participants.

  6. Forest cover change and fragmentation using Landsat data in Maçka State Forest Enterprise in Turkey.

    Cakir, Günay; Sivrikaya, Fatih; Keleş, Sedat

    2008-02-01

    Monitoring forest cover change and understanding the dynamic of forest cover is increasingly important in sustainable development and management of forest ecosystems. This paper uses remote sensing (RS) techniques to monitor forest cover change in Maçka State Forest Enterprise (MSFE) located in NE of Turkey through 1975 to 2000 and then analyses spatial and temporal changes in forest cover by Geographical Information Systems (GIS) and FRAGSTATStrade mark. Forest cover changes were detected from a time series of satellite images of Landsat MSS in 1975, Landsat TM in 1987, and Landsat ETM+ in 2000 using RS and GIS. The results showed that total forest area, productive forest area and degraded forest area increased while broadleaf forest area and non forest area decreased. Mixed forest and degraded forest increased during the first (1975-1987) period, but decreased during the second (1987-2000) period. During the whole study period, the annual forestation rate was 152 ha year(-1), equivalent to 0.27% year(-1) using the compound-interest-rate formula. The total number of patches increased from 36,204 to 48,092 (33%), and mean size of forest patch (MPS) decreased from 2.8 ha to 2.1 ha during a 25 year period. Number of smaller patches (patches in 0-100 ha size class) increased, indicating more fragmented landscape over time that might create a risk for the maintenance of biodiversity of the area. While total population increased from 1975 to 2000 (3.7%), rural population constantly decreased. The increase of forest areas may well be explained by the fact that demographic movement of rural areas concentrated into Maçka City Center. These figures also indicated that decrease in the rural population might likely lead to the release of human pressure to forest areas, probably resulting in a positive development of forest areas.

  7. Proposal for the Award of a Contract for the Supply of 13 kA and 20.5 kA, 18 V Switched-Mode Power Converters for the LHC

    2003-01-01

    This document concerns the award of a contract for the supply of 13 kA and 20.5 kA, 18 V switched-mode power converters using sub-converters of 3.25 kA. Following a market survey (MS-2866/SL/LHC) carried out among 81 firms in seventeen Member States and a call for tenders for prototypes (IT-2919/SL/LHC) sent on 11 June 2001, a call for tenders for the supply of the pre-series and series of 13 kA and 20.5 kA, 18 V switched-mode power converters both using sub-converters of 3.25 kA was sent to two firms on 17 September 2002. The Finance Committee is invited to agree to the negotiation of a contract with TRANSTECHNIK (DE), the only firm that has delivered a successfully qualifying prototype, for the supply of eighteen 13 kA and one 20.5 kA, 18 V switched-mode power converters and spares for a total amount of 4 607 731 euros (6 747 300 Swiss francs), not subject to revision. The rate of exchange used is that stipulated in the tender. The firm has indicated the following distribution by country of the contract val...

  8. Current neutralization of nanosecond risetime, high-current electron beam

    Lidestri, J.P.; Spence, P.W.; Bailey, V.L.; Putnam, S.D.; Fockler, J.; Eichenberger, C.; Champney, P.D.

    1991-01-01

    This paper reports that the authors have recently investigated methods to achieve current neutralization in fast risetime (<3 ns) electron beams propagating in low-pressure gas. For this investigation, they injected a 3-MV, 30-kA intense beam into a drift cell containing gas pressures from 0.10 to 20 torr. By using a fast net current monitor (100-ps risetime), it was possible to observe beam front gas breakdown phenomena and to optimize the drift cell gas pressure to achieve maximum current neutralization. Experimental observations have shown that by increasing the drift gas pressure (P ∼ 12.5 torr) to decrease the mean time between secondary electron/gas collisions, the beam can propagate with 90% current neutralization for the full beam pulsewidth (16 ns)

  9. Monitoring the Algerian Basin through glider observations, satellite altimetry and numerical simulations along a SARAL/AltiKa track

    Aulicino, G.; Cotroneo, Y.; Ruiz, S.; Sánchez Román, A.; Pascual, A.; Fusco, G.; Tintoré, J.; Budillon, G.

    2018-03-01

    The Algerian Basin is a key component of the general circulation in the Western Mediterranean Sea. The presence of both fresh Atlantic water and more saline Mediterranean water gives the basin an intense inflow/outflow regime and complex circulation patterns. Energetic mesoscale structures that evolve from meanders of the Algerian Current into isolated cyclonic and anticyclonic eddies dominate the area, with marked repercussions on biological activity. Despite its remarkable importance, this region and its variability are still poorly known and basin-wide knowledge of its meso- and submesoscale features is still incomplete. Studying such complex processes requires a synergistic approach that involves integrated observing systems. In recent years, several studies have demonstrated the advantages of combined use of autonomous underwater vehicles, such as gliders, with a new generation of satellite altimetry. In this context, we present results of an observational program conducted in the Algerian Basin during fall 2014 and 2015 that aimed to advance our knowledge of its main features. The study was carried out through analysis of high resolution glider observations, collected along the Algerian BAsin Circulation Unmanned Survey (ABACUS) chokepoint, in synergy with co-located SARAL/AltiKa altimetric products and CMEMS numerical simulations. Results show that glider-derived dynamic height and SARAL/AltiKa absolute dynamic topography have similar patterns, with RMS of the differences ranging between 1.11 and 2.90 cm. Even though larger discrepancies are observed near the Balearic and Algerian coasts, correlation coefficients between glider and satellite observations seem mostly to be affected by reduced synopticity between the measurements. Glider observations acquired during the four surveys reveal the presence of several water masses of Atlantic and Mediterranean origin (i.e., AW and LIW at different modification levels) with marked seasonal variability.

  10. Variational full wave calculation of fast wave current drive in DIII-D using the ALCYON code

    Becoulet, A.; Moreau, D.

    1992-04-01

    Initial fast wave current drive simulations performed with the ALCYON code for the 60 MHz DIII-D experiment are presented. Two typical shots of the 1991 summer campaign were selected with magnetic field intensities of 1 and 2 teslas respectively. The results for the wave electromagnetic field in the plasma chamber are displayed. They exhibit a strong enrichment of the poloidal mode number m-spectrum which leads to the upshift of the parallel wavenumber, κ perpendicular, and to the wave absorption. The m-spectrum is bounded when the local poloidal wavenumber reaches the Alfven wavenumber and the κ perpendicular upshifts do not destroy the wave directionality. Linear estimations of the driven current are made. The current density profiles are found to be peaked and we find that about 88 kA can be driven in the 1 tesla/1.7 keV phase with 1.7 MW coupled to the electrons. In the 2 tesla/3.4 keV case, 47 kA are driven with a total power of 1.5 MW, 44% of which are absorbed on the hydrogen minority, through the second harmonic ion cyclotron resonance. The global efficiency is then 0.18 x 10 19 A m -2 W -1 if one considers only the effective power going to the electrons

  11. pKa Determination of water-soluble calix[4]arenes

    Shinkai, Seiji; Araki, Koji; Grootenhuis, P.D.J.; Reinhoudt, David

    1991-01-01

    Neutral, water-soluble 5,11,17,23-tetrakis[bis-(2-hydroxyethyl)aminosulphonyl]calix[4]arene-25,26,27,28-tetraol and 5,11,17,23-tetranitrocalix[4]arene-25,26,27,28-tetraol have been synthesized and the pKa values of the OH groups determined in an aqueous system.

  12. Dynamic optical fiber delivery of Ka-band packet transmissions for wireless access networks

    Rodríguez Páez, Juan Sebastián; Madsen, Peter; Tafur Monroy, Idelfonso

    2017-01-01

    A Reconfigurable Radio Access Unit is presented and experimentally demonstrated. In the unit, an optical switching system is set to dynamically deliver different packets to different points in the network. The packets are transmitted wirelesslty on the Ka-band (26–40 GHz), achieving BER values...

  13. Ettevõtja saab raha ka otse Brüsselist / Silva Männik

    Männik, Silva, 1974-

    2004-01-01

    Lisaks mitmetele Eesti asutustele, mis alates sellest aastast EL-i struktuurifondide kaudu raha jagama hakkavad, on ettevõtjatel võimalik taotleda erinevate programmide kaudu raha ka otse EL-i eelarvest. Lisa: Otse saab raha taotleda mitmest programmist

  14. An integrated Ka/Ku-band payload for personal, mobile and private business communications

    Hayes, Edward J.; Keelty, J. Malcolm

    1991-01-01

    The Canadian Department of Communications has been studying options for a government-sponsored demonstration payload to be launched before the end of the century. A summary of the proposed system concepts and network architectures for providing an advanced private business network service at Ku-band and personal and mobile communications at Ka-band is presented. The system aspects addressed include coverage patterns, traffic capacity, and grade of service, multiple access options as well as special problems, such as Doppler in mobile applications. Earth terminal types and the advanced payload concept proposed in a feasibility study for the demonstration mission are described. This concept is a combined Ka-band/Ku-band payload which incorporates a number of advanced satellite technologies including a group demodulator to convert single-channel-per-carrier frequency division multiple access uplink signals to a time division multiplex downlink, on-board signal regeneration, and baseband switching to support packet switched data operation. The on-board processing capability of the payload provides a hubless VSAT architecture which permits single-hop full mesh interconnectivity. The Ka-band and Ku-band portions of the payload are fully integrated through an on-board switch, thereby providing the capability for fully integrated services, such as using the Ku-band VSAT terminals as gateway stations for the Ka-band personal and mobile communications services.

  15. Müügiga kimpus majaomanikud otsivad samal ajal ka rentnikke / Kaire Talviste

    Talviste, Kaire, 1979-

    2008-01-01

    Olukorrast eramute üüriturul: kinnisvaraportaalides on rendile pakkuda ligi paarsada maja, mida püütakse samal ajal ka edutult müüa, rendihinnad ulatuvad 30 000 - 50 000 kroonini kuus, eramuid üürivad peamiselt välismaalased

  16. Kas Roger Federer suudab Rafael Nadali alistada ka Pariisis? / Maarja Värv

    Värv, Maarja

    2007-01-01

    Prantsusmaa lahtiste tennisemeistrivõistluste eel on paljude jaoks suurim küsimus, kas maailma esinumber Roger Federer suudab lõpuks võita ka Roland Garros' esikoha ning astuda sammu suure slämmi suunas. Vt. samas: Maret Ani põhiturniirile ei pääsenud

  17. Evaluation and Performance Analysis of 3D Printing Technique for Ka-Band Antenna Production

    Armendariz, Unai; Rommel, Simon; Rodríguez Páez, Juan Sebastián

    2016-01-01

    This paper presents the design and fabrication of 3D printed WR-28 waveguide horn antennas operating in the Ka-band frequency range between 26.5GHz and 40GHz. Three antennas are fabricated from polylactide acid filaments in conductive and non-conductive variants; the latter is covered...

  18. A role for icebergs in the 8.2 ka climate event

    Wiersma, A.P.; Jongma, J.I.

    2009-01-01

    We investigate the potential role of icebergs in the 8.2 ka climate event, using a coupled climate model equipped with an iceberg component. First, we evaluate the effect of a large iceberg discharge originating from the decaying Laurentide ice sheet on ocean circulation, compared to a release of an

  19. Geological conditions of origin of the Potočka zijalka cave

    Stanko Buser

    2002-12-01

    Full Text Available In the Potočka zijalka cave on Mt. Ol{eva in Southern Karavanke during excavation of cave sediments of Würm age that contain cultural remains of the Cromagnon Man also large amounts of gravel were before the Badenian transgression, from the Central Alps during Miocene.

  20. Potential forcings of summer temperature variability of the southeastern Tibetan Plateau in the past 12 ka

    Zhang, Enlou; Chang, Jie; Sun, Weiwei; Cao, Yanmin; Langdon, Peter; Cheng, Jun

    2018-06-01

    Investigating potential forcing mechanisms of terrestrial summer temperature changes from the Asian summer monsoon influenced area is of importance to better understand the climate variability in these densely populated regions. The results of spectral and wavelet analyses of the published chironomid reconstructed mean July temperature data from Tiancai Lake on the SE Tibetan Plateau are presented. The evidence of solar forcing of the summer temperature variability from the site on centennial timescales where key solar periodicities (at 855 ± 40, 465 ± 40, 315 ± 40 and 165 ± 40 year) are revealed. By using a band-pass filter, coherent fluctuations were found in the strength of Asian summer monsoon, Northern Hemisphere high latitude climate and high elevation mid-latitude (26°N) terrestrial temperatures with solar sunspot cycles since about 7.6 ka. The two abrupt cooling events detected from the Tiancai Lake record, centered at ∼9.7 and 3.5 ka were examined respectively. Coupled with the paleoclimate modeling results, the early Holocene event (9.7 ka) is possibly linked to an ocean-atmospheric feedback mechanism whereas the latter event (3.5 ka) may be more directly related to external forcing.

  1. Mahepõllumajandus : [1999-2004, ka ökomärgist] / Peeter Prass

    Prass, Peeter

    2005-01-01

    Ilmunud ka: Agriculture and the development of rural life : overview 2004/2005. - Tallinn, 2005, lk.43-45. Hinnanguliselt moodustas 2004. a. mahepõllundusega hõivatud maa üldisest põllumajandusmaast alla 5%. Piimalehmadest olid maheloomad veidi üle 2%. Diagrammid

  2. Liha tootmine : [2000-2004 Eestis liikide kaupa, s.h. ka kitseliha] / Matti Piirsalu

    Piirsalu, Matti, 1947-

    2005-01-01

    Ilmunud ka: Agriculture and the development of rural life : overview 2004/2005. - Tallinn, 2005, lk. 20-22. 2004. a. vähenes sealihatoodang 3%, lamba- ja kitseliha toodang 25%.Veise- ja linnuliha tootmine kasvas kubki 5%. Tabel: Lihatoodang aastatel 2000-2004

  3. Damaška and the faces of international criminal justice

    Swart, B.

    2008-01-01

    Mirjan Damaška 's scholarly publications provide important insights for the analysis of systems of criminal justice at the international level. This is particularly true for his major book: The Faces of Justice and State Authority - A Comparative Approach to the Legal Process. The book develops

  4. Saja aasta asemel saaks maantee valmis ka kümnega / Jarno Laur

    Laur, Jarno, 1975-

    2006-01-01

    Ilmunud ka: Järva Teataja 9. märts lk. 2. Riigikogu liige sotsiaaldemokraatide fraktsiooni poolt Riigikogu menetlusse antud Tallinna-Tartu-Luhamaa maantee ehitamise otsuse eelnõust, otsuse vastuvõtmise vajalikkusest ning tee-ehituse rahastamisest

  5. Ac loss measurements on a superconducting transformer for a 25 kA superconducting rectifier

    ten Kate, Herman H.J.; Mulders, J.M.; de Reuver, J.L.; van de Klundert, L.J.M.

    1984-01-01

    Ac loss measurements have been performed on a superconducting transformer. The transformer is a part of a 25 kA thermally switched superconducting rectifier operating at a frequency of 0.1 Hz. The loss measurements have been automatized by means of a microcomputer sampling four relevant signals and

  6. Kolem Patočkovy politiky duchovního člověka

    Chvatík, Ivan

    2015-01-01

    Roč. 70, č. 6 (2015), s. 458-464 ISSN 0046-385X Institutional support: RVO:67985955 Keywords : philosophy * upswing to the political * meaning * history * solidarity of the shaken * Patočka Subject RIV: AA - Philosophy ; Religion

  7. Design considerations on a sparse array antenna for Ka-band spaceborne SAR applications

    Jacobs, S.; Bekers, D.; Monni, S.; Otten, M.; Van Rossum, W.; Gerini, G.; Germani, C.; Fortini, D.; Toso, G.

    2015-01-01

    This contribution addresses the problem of designing a sparse active array antenna for spaceborne SAR applications at Ka-band. The main driver for the design is limiting the recurring manufacturing costs associated to the number of active modules, while preserving main performance and insuring a

  8. Maailma esimene online-maakler teenindab ka eesti keeles / Romet Kreek

    Kreek, Romet, 1972-

    2005-01-01

    Maailma esimene online-maaklerfirma E*Trade avas eestikeelse kauplemiskeskkonna, kuhu lähikuudel lisandub võimalus kaubelda ka Eesti aktsiatega. Tabel: E*Trade pakub konkurentsi kohalikele maakleritele. Kommenteerib Peeter Koppel. Vt. samas: Lauri Matsulevitsh. LHV konkurenti ei karda

  9. Muusikamaailm : "Passioon 2000" Stuttgardis. Ojai festivalilt. Boulez dirigeerib ka Edinburghis. Placido Domingo Helsingis / Priit Kuusk

    Kuusk, Priit, 1938-

    2000-01-01

    Stuttgardi Rahvusvahelisel Bachi Akadeemia korraldataval Euroopa muusikafestivalil ettekandele tulevatest "tänapäevastest passioonidest". Ojai muusikafestivalist Jaapanis. P. Boulezi 75. sünnipäevale pühendatud kontserdisari "Boulez 2000" jõudis ka Edinburghi festivalile. P. Domingo kontserdist Helsingi olümpiastaadionil, K. Mattila kontserdist Helsingi Areenal

  10. Tallinna info- ja abitelefon toetab ka hättasattunud lapsi / Hille Tänavsuu

    Tänavsuu, Hille, 1941-2014

    2006-01-01

    Vt. ka Postimees : na russkom jazõke 16. jaan., lk. 5. Infotelefoni projektijuhi Herve Merivaldi sõnul ei sõanda lapsed lastekaitsetöötaja või politsei poole pöörduda. Abitelefonile helistades aitavad dispetsherid neil ühendust saada inimestega, kes neid aidata võivad

  11. Efficient Aerobic Oxidation of Cyclohexane to KA Oil Catalyzed by Pt ...

    127, No. 7, July 2015, pp. 1167–1172. c Indian Academy of Sciences. ... The catalyst was used for the partial oxidation of cyclohexane in a Parr type reactor. It was found that Pt-Sn supported on MWCNTs can act as an efficient catalyst for the partial ... version ratio with high selectivity for KA oil in a liquid ... These gases.

  12. Internetiside VoIP sobib ka ettevõtteile / Valdur Laid

    Laid, Valdur, 1969-

    2005-01-01

    Ilmunud ka: Delovõje Vedomosti 8. juuni lk. 19. Kommunikatsiooni liikumisest internetti ehk IP-võrku ning selle võimalustest ettevõtjaile. Vt. samas: Väikefirmade IP-lahendus jõuab aasta lõpus massturule

  13. Measurement technology of RF interference current in high current system

    Zhao, Zhihua; Li, Jianxuan; Zhang, Xiangming; Zhang, Lei

    2018-06-01

    Current probe is a detection method commonly used in electromagnetic compatibility. With the development of power electronics technology, the power level of power conversion devices is constantly increasing, and the power current of the electric energy conversion device in the electromagnetic launch system can reach 10kA. Current probe conventionally used in EMC (electromagnetic compatibility) detection cannot meet the test requirements on high current system due to the magnetic saturation problem. The conventional high current sensor is also not suitable for the RF (Radio Frequency) interference current measurement in high current power device due to the high noise level in the output of active amplifier. In this paper, a passive flexible current probe based on Rogowski coil and matching resistance is proposed that can withstand high current and has low noise level, to solve the measurement problems of interference current in high current power converter. And both differential mode and common mode current detection can be easily carried out with the proposed probe because of the probe's flexible structure.

  14. A 25 kA, 2T, 78 kJ, 52 litre superconducting test coil. Strength calculations and construction

    ten Kate, Herman H.J.; Holtslag, A.H.M.; Knoben, J.; Steffens, H.A.; van de Klundert, L.J.M.

    1983-01-01

    Within the scope of our research program for a 25 kA superconducting rectifier, we have built a 25 kA s.c. coil being a single layer solenoid with a bore of 0.45 meter and a volume of 52 litre. The starting point for the design was to avoid any metallic structural material. This unique coil consists

  15. Maksude tõstmine lööb nii ettevõtlust kui ka tavalist inimest / Mirko Ojakivi

    Ojakivi, Mirko

    2008-01-01

    Konjunktuuriinstituudi direktori Marje Josingu sõnul halvendaks maksutõus nii ettevõtluse konkurentsivõimet kui ka inimeste võimet eluga toime tulla, ka maksumaksjate liidu esimees Lasse Lehis peab maksude tõstmist valeks, eriti vale oleks tema väitel tõsta käibemaksu

  16. Morphotectonic control of the Białka drainage basin (Central Carpathians: Insights from DEM and morphometric analysis.

    Wołosiewicz Bartosz

    2016-06-01

    Full Text Available The Białka river valley is directly related to a deep NNW-SSE oriented fault zone. According to the results of previous morphometric analyses, the Białka drainage basin is one of the most tectonically active zones in the Central Carpathians. It is also located within an area of high seismic activity.

  17. Reconstruction of the eruptive activity on the NE sector of Stromboli volcano: timing of flank eruptions since 15 ka

    Calvari, S.; Branca, S.; Corsaro, R.A.; De Beni, E.; Miraglia, L.; Norini, G.; Wijbrans, J.R.; Boschi, E.

    2011-01-01

    A multidisciplinary geological and compositional investigation allowed us to reconstruct the occurrence of flank eruptions on the lower NE flank of Stromboli volcano since 15 ka. The oldest flank eruption recognised is Roisa, which occurred at ~15 ka during the Vancori period, and has transitional

  18. Risk Assessment of Mineral Groundwater Near Rogaška Slatina

    Trcek, Branka; Leis, Albrecht

    2017-10-01

    Groundwater resources of mineral and thermo-mineral water are invaluable for planning a sustainable spatial and economic development of the Rogaška Slatina area, which requires a protection of this natural heritage. Numerous previous investigations of Rogaška groundwaters were subjects to balneology and to demands for larger exploitation quantities, that is why information are missing that are essential for definition of the Rogaška fractured aquifer system with mineral and thermo-mineral water and for its protection. The isotopic investigations of groundwaters stored in the Rogaška Slatina fractured aquifer system were performed aiming at answering open questions on the groundwater recharge and dynamics, on connections between different types of aquifers and on solute transport. Environmental isotopes 2H, 18O, 3H, 13C of dissolved inorganic carbon and 14C were analysed in mineral, thermo-mineral and spring waters. Results indicated the source and mechanism of groundwater recharge, its renewability, a transit time distribution, hydraulic interrelationships, the groundwater origin and its evolution due to effects of water-rock interaction. The mean residence time estimates of mineral and thermo- mineral water in the aquifer are between 3400 and 14000 years. On the other hand, the mixing processes between younger and older waters or mineral and spring waters are reflected as well as waters that infiltrated predominantly after the 1960s. These suggest the vulnerability of the research systems to man-made impacts. The presented results coupled with available information on a physical hydrogeology and water chemistry asses the optimal balance between the environmental protection and economic use of mineral water resources in the study area. They are essential for the protection strategy development of mineral and thermo-mineral water in the Rogaška Slatina area bringing together the state administration and local authorities and stakeholders.

  19. KaBOB: ontology-based semantic integration of biomedical databases.

    Livingston, Kevin M; Bada, Michael; Baumgartner, William A; Hunter, Lawrence E

    2015-04-23

    The ability to query many independent biological databases using a common ontology-based semantic model would facilitate deeper integration and more effective utilization of these diverse and rapidly growing resources. Despite ongoing work moving toward shared data formats and linked identifiers, significant problems persist in semantic data integration in order to establish shared identity and shared meaning across heterogeneous biomedical data sources. We present five processes for semantic data integration that, when applied collectively, solve seven key problems. These processes include making explicit the differences between biomedical concepts and database records, aggregating sets of identifiers denoting the same biomedical concepts across data sources, and using declaratively represented forward-chaining rules to take information that is variably represented in source databases and integrating it into a consistent biomedical representation. We demonstrate these processes and solutions by presenting KaBOB (the Knowledge Base Of Biomedicine), a knowledge base of semantically integrated data from 18 prominent biomedical databases using common representations grounded in Open Biomedical Ontologies. An instance of KaBOB with data about humans and seven major model organisms can be built using on the order of 500 million RDF triples. All source code for building KaBOB is available under an open-source license. KaBOB is an integrated knowledge base of biomedical data representationally based in prominent, actively maintained Open Biomedical Ontologies, thus enabling queries of the underlying data in terms of biomedical concepts (e.g., genes and gene products, interactions and processes) rather than features of source-specific data schemas or file formats. KaBOB resolves many of the issues that routinely plague biomedical researchers intending to work with data from multiple data sources and provides a platform for ongoing data integration and development and for

  20. The 12.1 ka Middle Toluca Pumice: A dacitic Plinian subplinian eruption of Nevado de Toluca in Central Mexico

    Arce, J. L.; Cervantes, K. E.; Macías, J. L.; Mora, J. C.

    2005-10-01

    The Nevado de Toluca volcano erupted explosively approximately 12.1 ka ago, producing a Plinian-subplinian eruption that deposited the Middle Toluca Pumice (MTP). The MTP consists of white and gray juvenile pumice, gray dense juvenile lapilli, and red altered lithic lapilli. The pumice is dacitic (63.54-65.06 wt.% SiO 2) with phenocrysts of plagioclase > orthopyroxene > hornblende ± ilmenite and titanomagnetite, and biotite xenocrysts set in a groundmass of rhyolitic glass (70-71 wt.% SiO 2). The MTP has a dispersal axis to the ESE covering an area of 92 km 2, with a minimum volume of 1.8 km 3 (DRE). Stratigraphic relations, grain size, componentry, and vesicularity analyses suggest that the eruption occurred in five major phases: (1) an opening magmatic phase that generated a 20-km-high Plinian column dispersed to the SE; (2) a hydromagmatic explosion followed with the establishment of a subplinian eruptive column (18-19 km high) dispersed tephra to the SE and gradually waned; (3) hydromagmatic explosions emplaced dilute pyroclastic density currents followed by the formation of an eruptive column of unknown height; (4) immediately after, a new magmatic explosion established another eruptive column; and (5) the collapse of the latter column generated two pumiceous pyroclastic density currents that were fully dilute proximally, but transformed into two granular-fluid pyroclastic currents that traveled 19 km from the source.

  1. A Fiber-Optic Aircraft Lightning Current Measurement Sensor

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

    2013-01-01

    A fiber-optic current sensor based on the Faraday Effect is developed for aircraft installations. It can measure total lightning current amplitudes and waveforms, including continuing current. Additional benefits include being small, lightweight, non-conducting, safe from electromagnetic interference, and free of hysteresis and saturation. The Faraday Effect causes light polarization to rotate in presence of magnetic field in the direction of light propagation. Measuring the total induced light polarization change yields the total current enclosed. The system operates at 1310nm laser wavelength and can measure approximately 300 A - 300 kA, a 60 dB range. A reflective polarimetric scheme is used, where the light polarization change is measured after a round-trip propagation through the fiber. A two-detector setup measures the two orthogonal polarizations for noise subtraction and improved dynamic range. The current response curve is non-linear and requires a simple spline-fit correction. Effects of high current were achieved in laboratory using combinations of multiple fiber and wire loops. Good result comparisons against reference sensors were achieved up to 300 kA. Accurate measurements on a simulated aircraft fuselage and an internal structure illustrate capabilities that maybe difficult with traditional sensors. Also tested at a commercial lightning test facility from 20 kA to 200 kA, accuracy within 3-10% was achieved even with non-optimum setups.

  2. Current control by ECCD for W7-X

    Turkin, Yu.; Maassberg, H.; Beidler, C.D.; Geiger, J.; Marushchenko, N.B.

    2005-01-01

    One of the optimization criteria for the stellarator W7-X is the minimization of the bootstrap current. The plasma current changes the magnetic configuration, especially near the plasma edge, where X-points and islands are located. It was shown that the plasma parameter distributions in the divertor region and the particle and energy depositions on the divertor plates depend strongly on the island geometry. An estimation of the tolerable plasma current obtained from the shift of the island structure close to the target plates shows that the plasma current should be controlled within a range of about 10 kA. The bootstrap current even for the standard configuration can easily exceed this value. The W7-X is not equipped with an Ohmic transformer, so the only means for compensating this current is electron cyclotron current drive (ECCD) and/or neutral beam current drive (NBCD). In this report we study the compensation of residual bootstrap current by using ECCD. To model the control of the toroidal current we use a predictive 1D transport code, which is under development. For evaluation of the bootstrap current and neoclassical transport coefficients we use results from an international collaboration on neoclassical transport in stellarators. Power deposition and current drive profiles due to electron cyclotron resonance heating are calculated by a new ray tracing code. The modeling showed that the loop voltage induced by ECCD leads to a redistribution of the current density with the diffusion time of about two seconds. The relaxation time of the total current is much longer than this time - for a typical ECRH-plasma the total toroidal current reaches steady state after several L/R-time that is about hundreds of seconds. In order to keep current in an acceptable range and to avoid long relaxation times we propose Feed-forward or Predictive control using ECCD as actuator, the steps are as follows: - calculate the bootstrap current distribution using measured plasma

  3. submitter Design and Manufacturing of a 45 kA at 10 T REBCO-CORC Cable-in-Conduit Conductor for Large-Scale Magnets

    Mulder, Tim; Mentink, Matthias; Silva, Helder; van der Laan, Danko; Dhalle, Marc; ten Kate, Herman

    2016-01-01

    The European Organization for Nuclear Research (CERN) is developing high-current ReBCO-CORC strand-based cables for use in future large-scale detector magnets. A six-around-one, forced flow gas-cooled ReBCO-CORC cable-in-conduit conductor (CICC) is envisioned for application in magnets operating in the 20-40 K temperature range. A CICC, rated for 45 kA at 4.2 K and 10 T, is designed and in production. The CICC comprises a cable of six CORC strands helically wound around a tube. The cable has an expected current density of 105 $A/mm^2$ at 10 T/4.2 K, which corresponds to an overall current density of 53 $A/mm^2$. A cable current density of 110 $A/mm^2$ can be reached when increasing the temperature to 20 K and operating in a magnetic field of 5 T.

  4. Superconducting solenoid designed for 400 kJ at 25 kA under conditions of fast discharge and field reversal

    Weldon, D.; Chowdhuri, P.; Honig, M.; Rogers, J.D.; Thullen, P.

    1981-05-01

    A 1.26-mH superconducting solenoid made of NbTi and Cu-CuNi mixed matrix superconductor was designed and fabricated by Westinghouse Electric Corporation for the Los Alamos National Laboratory as part of the pulsed energy storage coil program. The coil was designed to store 400 kJ at a current of 25 kA and has been operated to currents of 20 kA. Development of high current cables and low-loss superconductors are both necessary undertakings for future fusion devices. The first tests of the coil involved a very slow charge of the coil followed by a rapid discharge in 1.07 ms with a capacitor bank and a normal-conductor load coil in a resonant L-C-L circuit. The second test consisted of a slow charge followed by a discharge and recharge on a time scale of a few seconds. This latter cycle resembles that expected in a tokamak induction coil. Loss measurements were made by an electrical method during the second series of tests

  5. Sensitivity of in vivo X-ray fluorescence determination of skeletal lead stores

    Sokas, R.K.; Besarab, A.; McDiarmid, M.A.; Shapiro, I.M.; Bloch, P.

    1990-01-01

    Eighteen patients with known past occupational lead exposure underwent parenteral diagnostic chelation with ethylenediaminetetraacetic acid and x-ray fluorescent determination of in vivo skeletal lead stores at the distal styloid process of the ulna and at the temporal base bone using a cobalt 57 source and measuring lead Ka x-rays. X-ray fluorescent lead measurements in both locations correlated with results of diagnostic chelation. Using a post-chelation urinary excretion of greater than 600 micrograms lead/24 h as the definition of high-lead stores, sensitivity of x-ray fluorescence at the wrist and temple was 56% and 39%, respectively

  6. Fitful and protracted magma assembly leading to a giant eruption, Youngest Toba Tuff, Indonesia

    Reid, Mary R; Vazquez, Jorge A.

    2017-01-01

    The paroxysmal eruption of the 74 ka Youngest Toba Tuff (YTT) of northern Sumatra produced an extraordinary 2800 km3 of non-welded to densely welded ignimbrite and co-ignimbrite ash-fall. We report insights into the duration of YTT magma assembly obtained from ion microprobe U-Th and U-Pb dates, including continuous age spectra over >50% of final zircon growth, for pumices and a welded tuff spanning the compositional range of the YTT. A relatively large subpopulation of zircon crystals nucleated before the penultimate caldera-related eruption at 501 ka, but most zircons yielded interior dates 100-300 ka thereafter. Zircon nucleation and growth was likely episodic and from diverse conditions over protracted time intervals of >100 to >500 ka. Final zircon growth is evident as thin rim plateaus that are in Th/U chemical equilibrium with hosts, and that give crystallization ages within tens of ka of eruption. The longevity and chemical characteristics of the YTT zircons, as well as evidence for intermittent zircon isolation and remobilization associated with magma recharge, is especially favored at the cool and wet eutectoid conditions that characterize at least half of the YTT, wherein heat fluxes could dissolve major phases but have only a minor effect on larger zircon crystals. Repeated magma recharge may have contributed to the development of compositional zoning in the YTT but, considered together with limited allanite, quartz, and other mineral dating and geospeedometry, regular perturbations to the magma reservoir over >400 ka did not lead to eruption until 74 ka ago.

  7. Revalidation and rationale for high pKa values of unconjugated bilirubin

    Ostrow J Donald

    2007-05-01

    Full Text Available Abstract Background Our prior solvent partition analysis, published in 1992, yielded pKa values for unconjugated bilirubin of about 8.1 and 8.4, but these results have been challenged and studies by other methods have suggested pKa values below 5.0. Methods We repeated our published solvent partition studies, using 14C-unconjugated bilirubin highly purified by extraction of residual labeled impurities from CHCl3 into an aqueous buffer, pH 7.0. Partition ratios at six pH values from 5.0 to 9.0 were determined by radioassay and compared with our prior values obtained by diazo assay. Results At pH values ranging from 4.8 to 9.2, stable aqueous/chloroform 14C-partition ratios did not differ significantly from our published partition ratios based on diazo assay. Conclusion These results support the high pKa values of unconjugated bilirubin, above 8.0, derived from our earlier solvent partition study. In both studies, our measurements were based on the rapid analysis of clearly under-saturated solutions of highly-purified bilirubin over a wide pH range, using properly purified and preserved solvents. No previous direct estimate of the aqueous pKa values of unconjugated bilirubin meets all these preconditions. Three theoretical factors acting in combination, each related to the unique, extensive internal H-bonding of the -COOH groups, are proposed to support high pKa values of unconjugated bilirubin in water: a donation of an H-bond from the -OH moiety of the -COOH group, which is broken on ionization; b hindered solvation of the -COO- group after ionization; and c restricted rotation of the -COO- and -COOH groups. Our findings and rationale rebut methodological and theoretical criticisms leveled against our prior work. High pKa values for unconjugated bilirubin dictate that: a bilirubin diacid, which readily diffuses across membranes and can cause neurotoxicity, is the dominant unbound bilirubin species of unconjugated bilirubin in plasma at

  8. Lead levels - blood

    Blood lead levels ... is used to screen people at risk for lead poisoning. This may include industrial workers and children ... also used to measure how well treatment for lead poisoning is working. Lead is common in the ...

  9. Lead Poisoning Prevention Tips

    ... or removed safely. How are children exposed to lead? Lead-based paint and lead contaminated dust are ... What can be done to prevent exposure to lead? It is important to determine the construction year ...

  10. Superconducting magnets and leads thereto

    Biltcliffe, M.N.; Hanley, P.E.; McKinnon, J.B.; Wheatley, R.W.

    1975-01-01

    The magnet described comprises a cryostat containing a superconducting coil for the generation of a magnetic field, with a short-circuiting superconducting link connected across the coil, and electrical leads extending through the cryostat to the coil; these leads are provided with joints within the cryostat to enable them to be detached from the coil and removed from the cryostat without interrupting the current through the coil, thus reducing heat conduction to the cryostat through the leads. The joints are arranged so that the leads can be readily detached and re-attached to the coil from outside the cryostat. Gas-tight seals are provided where the leads pass through the outer wall of the cryostat, with caps that can be secured after removal of the leads. This kind of magnet can provide a stable magnetic field continuously over long periods, such as is required in nuclear magnetic resonance spectrometers. (U.K.)

  11. A Novel Low-cost, Ka-band, High Altitude, Multi-Baseline Unmanned Aerial Vehicle Sensor for Surface Water Ocean Topography, Phase II

    National Aeronautics and Space Administration — This proposal presents the Ka-band SWOT Phenomenology Airborne Radar (KaSPAR) to support the surface water ocean topography (SWOT) mission for science and algorithm...

  12. First tests of twisted-pair HTS 1 kA range cables for use in superconducting links

    Ballarino, A; Hurte, J; Sitko, M; Willering, G

    2011-01-01

    The requirement at CERN for 1 kA range High Temperature Superconducting (HTS) cables optimized for long electrical transfer has led to the design and assembly of a novel type of cable that can be made from pre-reacted MgB2, Bi-2223 or YBCO tapes. The cable consists of an assembly of twisted pairs, each of which is made from three superconducting tapes with the required copper stabilizer. The twisted pair cable is designed to transfer a DC current of ± 600 A in helium gas environment. The paper reports on the results of the electrical tests performed on twisted-pair cables of identical structure and made from commercially available MgB2, Bi-2223 and YBCO tapes. The twist pitch of the cables is adapted to match the mechanical properties of the different superconductors. Critical current tests were performed at both liquid helium and liquid nitrogen temperature. The electrical performance of several cables made from different conductors is reported and compared.

  13. Polonium-210 and lead-210 in the Southern Polar Ocean: Naturally occurring tracers of biological and hydrographical processes in the surface waters of the Antarctic Circumpolar Current and the Weddell Sea

    Friedrich, J.

    1997-01-01

    In this thesis the distribution of 210 Po and 210 Pb in the upper 600 m of the Antarctic Circumpolar Current and the Weddell Sea was investigated along north-south transects in austral spring and autumn. 210 Po and 210 Pb can serve as sensitive tracers for the special hydrographic conditions of the Antarctic Circumpolar Current and the Weddell Sea as well as for biological processes during phytoplankton blooms. The 210 Po/ 210 Pb disequilibrium was used as a tracer for particle export. This tracer integrates export on a timescale of 276 days because of the 138 day half-life of 210 Po and complements the 234 Th/ 238 U disequilibrium as another tracer for plankton production and export on a shorter timescale of several weeks. (orig.) [de

  14. Food safety assessment of Cry8Ka5 mutant protein using Cry1Ac as a control Bt protein.

    Farias, Davi Felipe; Viana, Martônio Ponte; Oliveira, Gustavo Ramos; Santos, Vanessa Olinto; Pinto, Clidia Eduarda Moreira; Viana, Daniel Araújo; Vasconcelos, Ilka Maria; Grossi-de-Sa, Maria Fátima; Carvalho, Ana Fontenele Urano

    2015-07-01

    Cry8Ka5 is a mutant protein from Bacillus thuringiensis (Bt) that has been proposed for developing transgenic plants due to promising activity against coleopterans, like Anthonomus grandis (the major pest of Brazilian cotton culture). Thus, an early food safety assessment of Cry8Ka5 protein could provide valuable information to support its use as a harmless biotechnological tool. This study aimed to evaluate the food safety of Cry8Ka5 protein following the two-tiered approach, based on weights of evidence, proposed by ILSI. Cry1Ac protein was used as a control Bt protein. The history of safe use revealed no convincing hazard reports for Bt pesticides and three-domain Cry proteins. The bioinformatics analysis with the primary amino acids sequence of Cry8Ka5 showed no similarity to any known toxic, antinutritional or allergenic proteins. The mode of action of Cry proteins is well understood and their fine specificity is restricted to insects. Cry8Ka5 and Cry1Ac proteins were rapidly degraded in simulated gastric fluid, but were resistant to simulated intestinal fluid and heat treatment. The LD50 for Cry8Ka5 and Cry1Ac was >5000 mg/kg body weight when administered by gavage in mice. Thus, no expected relevant risks are associated with the consumption of Cry8Ka5 protein. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. pKa-critical Interpretations of Solubility–pH Profiles: PG 300995 and NSC-639829 Case Studies

    George Butcher

    2015-07-01

    Full Text Available Two weak bases, PG-300995 (anti-HIV agent and NSC-639829 (anti-tumor agent, whose log S – pH profiles had been previously published, but whose pKa values had not been reported, were analyzed using a method which can determine pKa values from log S – pH data. This “SpH-pKa” technique, although often practiced, can result in inaccurate pKa values, for a variety of reasons. The operational SpH-pKa values were compared to those predicted by MarvinSketch (ChemAxon, ADMET Predictor (Simulation Plus, and ACD/Percepta (ACD/Labs. The agreement for the sparingly-soluble PG-300995 was reasonably good. However, a substantial difference was found for the practically-insoluble NSC-639829. To probe this further, the pKa of NSC‑639829 was measured by an independent spectrophotometric cosolvent technique. The log S - pH profile of NSC-639829 was then re‑analyzed with the independently-measured pKa. It was found that the equilibrium model which best fit the solubility data is consistent with the presence of a monocationic NSC-639829 dimeric species below pH 4. This illustrates that an independently-determined accurate pKa is critical to mechanistic interpretations of solubility-pH data. Apparently, the Henderson-Hasselbalch equation holds for PG-300995, but not NSC-639829.

  16. Modeling of the anode surface deformation in high-current vacuum arcs with AMF contacts

    Huang, Xiaolong; Wang, Lijun; Deng, Jie; Jia, Shenli; Qin, Kang; Shi, Zongqian

    2016-01-01

    A high-current vacuum arc subjected to an axial magnetic field is maintained in a diffuse status. With an increase in arc current, the energy carried by the arc column to the anode becomes larger and finally leads to the anode temperature exceeding the melting point of the anode material. When the anode melting pool is formed, and the rotational plasma of the arc column delivers its momentum to the melting pool, the anode melting pool starts to rotate and also flow outwards along the radial direction, which has been photographed by some researchers using high-speed cameras. In this paper, the anode temperature and melting status is calculated using the melting and solidification model. The swirl flow of the anode melting pool and deformation of the anode is calculated using the magneto-hydrodynamic (MHD) model with the volume of fraction (VOF) method. All the models are transient 2D axial-rotational symmetric models. The influence of the impaction force of the arc plasma, electromagnetic force, viscosity force, and surface tension of the liquid metal are all considered in the model. The heat flux density injected into the anode and the arc pressure are obtained from the 3D numerical simulation of the high-current vacuum arc using the MHD model, which gives more realistic parameters for the anode simulation. Simulation results show that the depth of the anode melting pool increases with an increase in the arc current. Some droplets sputter out from the anode surface, which is caused by the inertial centrifugal force of the rotational melting pool and strong plasma pressure. Compared with the previous anode melting model without consideration of anode deformation, when the deformation and swirl flow of the anode melting pool are considered, the anode temperature is relatively lower, and just a little more than the melting point of Cu. This is because of liquid droplets sputtering out of the anode surface taking much of the energy away from the anode surface. The

  17. ATLAS operations in the GridKa T1/T2 Cloud

    Duckeck, G; Serfon, C; Walker, R; Harenberg, T; Kalinin, S; Schultes, J; Kawamura, G; Leffhalm, K; Meyer, J; Nderitu, S; Olszewski, A; Petzold, A; Sundermann, J E

    2011-01-01

    The ATLAS GridKa cloud consists of the GridKa Tier1 centre and 12 Tier2 sites from five countries associated to it. Over the last years a well defined and tested operation model evolved. Several core cloud services need to be operated and closely monitored: distributed data management, involving data replication, deletion and consistency checks; support for ATLAS production activities, which includes Monte Carlo simulation, reprocessing and pilot factory operation; continuous checks of data availability and performance for user analysis; software installation and database setup. Of crucial importance is good communication between sites, operations team and ATLAS as well as efficient cloud level monitoring tools. The paper gives an overview of the operations model and ATLAS services within the cloud.

  18. Reconfigurable phased antenna array for extending cubesat operations to Ka-band: Design and feasibility

    Buttazzoni, G.; Comisso, M.; Cuttin, A.; Fragiacomo, M.; Vescovo, R.; Vincenti Gatti, R.

    2017-08-01

    Started as educational tools, CubeSats have immediately encountered the favor of the scientific community, subsequently becoming viable platforms for research and commercial applications. To ensure competitive data rates, some pioneers have started to explore the usage of the Ka-band beside the conventional amateur radio frequencies. In this context, this study proposes a phased antenna array design for Ka-band downlink operations consisting of 8×8 circularly polarized subarrays of microstrip patches filling one face of a single CubeSat unit. The conceived structure is developed to support 1.5 GHz bandwidth and dual-task missions, whose feasibility is verified by proper link budgets. The dual-task operations are enabled by a low-complexity phase-only control algorithm that provides pattern reconfigurability in order to satisfy both orbiting and intersatellite missions, while remaining adherent to the cost-effective CubeSat paradigm.

  19. Comparison of excitotoxic profiles of ATPA, AMPA, KA and NMDA in organotypic hippocampal slice cultures

    Kristensen, Bjarne Winther; Noraberg, J; Zimmer, J

    2001-01-01

    ) values was found after 2 days of exposure: AMPA (3.7 mM)>NMDA (11 mM)=KA (13 mM)>ATPA (33 mM). Exposed to 30 microM ATPA, 3 microM AMPA and 10 microM NMDA, CA1 was the most susceptible subfield followed by fascia dentata and CA3. Using 8 microM KA, CA3 was the most susceptible subfield, followed...... by fascia dentata and CA1. In 100 microM concentrations, all four agonists induced the same, maximal PI uptake in all hippocampal subfields, corresponding to total neuronal degeneration. Using glutamate receptor antagonists, like GYKI 52466, NBQX and MK-801, inhibition data revealed that AMPA excitotoxicity...

  20. Ka-band InSAR Imaging and Analysis Based on IMU Data

    Shi Jun

    2014-02-01

    Full Text Available Compared with other bands, the millimeter wave Interferometric Synthetic Aperture Radar (InSAR has high accuracy and small size, which is a hot topic in InSAR research. On the other hand, shorter wavelength causes difficulties in 2D imaging and interferometric phase extraction. In this study, the imaging and phase performance of the streaming Back Projection (BP method combined with IMU data are analyzed and discussed on the basis of actual Ka-band InSAR data. It is found that because the wavelength of the Ka-band is short, it is more sensitive to the antenna phase-center history. To ensure the phase-preserving capacity, the IMU data must be used with accurate motion error compensation. Furthermore, during data processing, we verify the flat-earth-removing capacity of the BP algorithm that calculates and compensates the master and slave antenna phase centers individually.

  1. Superconducting fault current limiter for railway transport

    Fisher, L. M., E-mail: LMFisher@niitfa.ru; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V. [National Technical Physics and Automation Research Institute (Russian Federation)

    2015-12-15

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with voltage of 3.5 kV and nominal current of 2 kA is developed. The SFCL consists of two series-connected units: block of superconducting modules and high-speed vacuum breaker with total disconnection time not more than 8 ms. The results of laboratory tests of superconducting SFCL modules in current limiting mode are presented. The recovery time of superconductivity is experimentally determined. The possibility of application of SFCL on traction substations of Russian Railways is considered.

  2. Transformer current sensor for superconducting magnetic coils

    Shen, S.S.; Wilson, C.T.

    1985-04-16

    The present invention is a current transformer for operating currents larger than 2kA (two kiloamps) that is capable of detecting a millivolt level resistive voltage in the presence of a large inductive voltage. Specifically, the present invention includes substantially cylindrical primary turns arranged to carry a primary current and substantially cylindrical secondary turns arranged coaxially with and only partially within the primary turns, the secondary turns including an active winding and a dummy winding, the active and dummy windings being coaxial, longitudinally separated and arranged to mutually cancel voltages excited by commonly experienced magnetic fields, the active winding but not the dummy winding being arranged within the primary turns.

  3. Compact high-current, subnanosecond electron accelerator

    Shpak, V G; Shunajlov, S A; Ulmaskulov, M R; Yalandin, M I [Russian Academy of Sciences, Ekaterinburg (Russian Federation). Inst. of Electrophysics; Pegel, I V [Russian Academy of Sciences, Tomsk (Russian Federation). High-Current Electronics Inst.; Tarakanov, V P [Russian Academy of Sciences, Moscow (Russian Federation). High-Temperature Inst.

    1997-12-31

    A compact subnanosecond, high-current electron accelerator producing an annular electron beam of duration up to 300 - 400 ps, energy about 250 keV, and current up to 1 kA has been developed to study transient processes in pulsed power microwave devices. The measuring and recording techniques used to experimentally investigate the dynamics of the beam current pulse and the transformation of the electron energy during the transportation of the beam in a longitudinal magnetic field are described. The experimental data obtained are compared with the predictions of a numerical simulation. (author). 6 figs., 5 refs.

  4. Superconducting fault current limiter for railway transport

    Fisher, L. M.; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V.

    2015-01-01

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with voltage of 3.5 kV and nominal current of 2 kA is developed. The SFCL consists of two series-connected units: block of superconducting modules and high-speed vacuum breaker with total disconnection time not more than 8 ms. The results of laboratory tests of superconducting SFCL modules in current limiting mode are presented. The recovery time of superconductivity is experimentally determined. The possibility of application of SFCL on traction substations of Russian Railways is considered

  5. Predicting the pKa and stability of organic acids and bases at an oil-water interface.

    Andersson, M P; Olsson, M H M; Stipp, S L S

    2014-06-10

    We have used density functional theory and the implicit solvent model, COSMO-RS, to investigate how the acidity constant, pKa, of organic acids and bases adsorbed at the organic compound-aqueous solution interface changes, compared to its value in the aqueous phase. The pKa determine the surface charge density of the molecules that accumulate at the fluid-fluid interface. We have estimated the pKa by comparing the stability of the protonated and unprotonated forms of a series of molecules in the bulk aqueous solution and at an interface where parts of each molecule reside in the hydrophobic phase and the rest remains in the hydrophilic phase. We found that the pKa for acids is shifted by ∼1 pH unit to higher values compared to the bulk water pKa, whereas they are shifted to lower values by a similar amount for bases. Because this pKa shift is similar in magnitude for each of the molecules studied, we propose that the pKa for molecules at a water-organic compound interface can easily be predicted by adding a small shift to the aqueous pKa. This shift is general and correlates with the functional group. We also found that the relative composition of molecules at the fluid-fluid interface is not the same as in the bulk. For example, species such as carboxylic acids are enriched at the interface, where they can dominate surface properties, even when they are a modest component in the bulk fluid. For high surface concentrations of carboxylic acid groups at an interface, such as a self-assembled monolayer, we have demonstrated that the pKa depends on the degree of deprotonation through direct hydrogen bonding between protonated and deprotonated acidic headgroups.

  6. Determination of pKa values of diastereomers of phosphinic pseudopeptides by CZE

    Koval, Dušan; Kašička, Václav; Jiráček, Jiří; Collinsová, Michaela

    2006-01-01

    Roč. 27, č. 23 (2006), s. 4648-4657 ISSN 0173-0835 R&D Projects: GA ČR(CZ) GA203/04/0098; GA ČR(CZ) GA203/05/2539 Institutional research plan: CEZ:AV0Z40550506 Keywords : diastereomer separation * phosphinic pseudopeptides * pKa determination Subject RIV: CC - Organic Chemistry Impact factor: 4.101, year: 2006

  7. Prediction of pKa values using the PM6 semiempirical method

    Jimmy C. Kromann

    2016-08-01

    Full Text Available The PM6 semiempirical method and the dispersion and hydrogen bond-corrected PM6-D3H+ method are used together with the SMD and COSMO continuum solvation models to predict pKa values of pyridines, alcohols, phenols, benzoic acids, carboxylic acids, and phenols using isodesmic reactions and compared to published ab initio results. The pKa values of pyridines, alcohols, phenols, and benzoic acids considered in this study can generally be predicted with PM6 and ab initio methods to within the same overall accuracy, with average mean absolute differences (MADs of 0.6–0.7 pH units. For carboxylic acids, the accuracy (0.7–1.0 pH units is also comparable to ab initio results if a single outlier is removed. For primary, secondary, and tertiary amines the accuracy is, respectively, similar (0.5–0.6, slightly worse (0.5–1.0, and worse (1.0–2.5, provided that di- and tri-ethylamine are used as reference molecules for secondary and tertiary amines. When applied to a drug-like molecule where an empirical pKa predictor exhibits a large (4.9 pH unit error, we find that the errors for PM6-based predictions are roughly the same in magnitude but opposite in sign. As a result, most of the PM6-based methods predict the correct protonation state at physiological pH, while the empirical predictor does not. The computational cost is around 2–5 min per conformer per core processor, making PM6-based pKa prediction computationally efficient enough to be used for high-throughput screening using on the order of 100 core processors.

  8. A K/Ka band radiating element for Tx/Rx phased array

    Sandhu, Ali Imran; Arnieri, E.; Amendola, G.; Boccia, L.; Meniconi, E.; Ziegler, V.

    2017-01-01

    The paper presents a K/Ka band radiating element for TX/RX phased arrays. Dual band operations is obtained using a single radiating surface: a novel radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The array elements are optimized to scan the beam in excess of 50° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  9. Pöffi filme näeb ka Ida-Virumaal

    2005-01-01

    Avatakse IX Pimedate Ööde Filmifestivali põhiprogramm, millest osa linastub ka Jõhvis ja Narvas. Lisatud PÖFFi programm Narva kultuurikeskuses Rugodiv ja dokumentaalfilmi "Sügavas kurgus" tutvustus : režissöörid Fenton Bailey, Randy Barbato : Ameerika Ühendriigid 2005. Film käsitleb 1972.a. kurikuulsa pornofilmi "Sügav kurk" ("Deep Throat") fenomeni

  10. Rimi toob Eesti liha lettidele ka Poola kaudu / Urmas Jaagant, Agnes Ojala

    Jaagant, Urmas

    2010-01-01

    Lihatootjate ja Poolas asuvat pakendamiskeskust pidava Hilton Foodsi vahel jätkuvad läbirääkimised, et sõlmida ekspordilepingud. Hilton Foods töötleb ja pakendab nii Eesti kui ka teiste riikide liha ning müüb selle Rimi kaubamärgi all Leedu, Läti, Ungari, Eesti jt. riikide poodidele. Rimi turundusjuhi Evelin Mägioja selgitusi

  11. Töötaja leiab ka miinimumpalgaga / Ralf-Martin Soe

    Soe, Ralf-Martin

    2007-01-01

    Ilmunud ka: Delovõje Vedomosti 31. okt. lk. 6. Madalate palkade TOP 10. Vt. samas: Küsimustele vastab Helter-R-i tegevjuht Kalev Kivipalu; Madal palk toob kaela maksuameti luubi alla sattumise; Endised töötajad: Helter-R-is sain palka osaliselt sulas; Tagant teine: suur juveelitootja - keskmine palk 3400 krooni kuus; Tagant kolmas koht: maksuamet uuris väikseid palku; Tabel. Kommenteerib Ruth Laatre

  12. Žumberačka Gora – Transformation from a Refuge to an Exodus Zone

    Crkvenčić, Ivan

    2002-01-01

    This article provides an analysis of the problem of immigration from Žumberačka gora, a highland region that lies on the border between Croatia and Slovenia. Due consideration is given to its border-zone character, basic features and later colonization during the mid-sixteenth century. A dual social organization and even social relations emerged in the region, reflecting the contrast between the Military Frontier and the civilian portion. The consequences of long settlement and secondary colo...

  13. A K/Ka band radiating element for Tx/Rx phased array

    Sandhu, Ali Imran

    2017-01-20

    The paper presents a K/Ka band radiating element for TX/RX phased arrays. Dual band operations is obtained using a single radiating surface: a novel radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The array elements are optimized to scan the beam in excess of 50° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  14. Safe leads and lead changes in competitive team sports

    Clauset, A.; Kogan, M.; Redner, S.

    2015-06-01

    We investigate the time evolution of lead changes within individual games of competitive team sports. Exploiting ideas from the theory of random walks, the number of lead changes within a single game follows a Gaussian distribution. We show that the probability that the last lead change and the time of the largest lead size are governed by the same arcsine law, a bimodal distribution that diverges at the start and at the end of the game. We also determine the probability that a given lead is "safe" as a function of its size L and game time t . Our predictions generally agree with comprehensive data on more than 1.25 million scoring events in roughly 40 000 games across four professional or semiprofessional team sports, and are more accurate than popular heuristics currently used in sports analytics.

  15. Descriptional Complexity of the Languages KaL: Automata, Monoids and Varieties

    Ondřej Klíma

    2010-08-01

    Full Text Available The first step when forming the polynomial hierarchies of languages is to consider languages of the form KaL where K and L are over a finite alphabet A and from a given variety V of languages, a being a letter from A. All such KaL's generate the variety of languages BPol1(V. We estimate the numerical parameters of the language KaL in terms of their values for K and L. These parameters include the state complexity of the minimal complete DFA and the size of the syntactic monoids. We also estimate the cardinality of the image of A* in the Schuetzenberger product of the syntactic monoids of K and L. In these three cases we obtain the optimal bounds. Finally, we also consider estimates for the cardinalities of free monoids in the variety of monoids corresponding to BPol1(V in terms of sizes of the free monoids in the variety of monoids corresponding to V.

  16. DelPhiPKa web server: predicting pKa of proteins, RNAs and DNAs.

    Wang, Lin; Zhang, Min; Alexov, Emil

    2016-02-15

    A new pKa prediction web server is released, which implements DelPhi Gaussian dielectric function to calculate electrostatic potentials generated by charges of biomolecules. Topology parameters are extended to include atomic information of nucleotides of RNA and DNA, which extends the capability of pKa calculations beyond proteins. The web server allows the end-user to protonate the biomolecule at particular pH based on calculated pKa values and provides the downloadable file in PQR format. Several tests are performed to benchmark the accuracy and speed of the protocol. The web server follows a client-server architecture built on PHP and HTML and utilizes DelPhiPKa program. The computation is performed on the Palmetto supercomputer cluster and results/download links are given back to the end-user via http protocol. The web server takes advantage of MPI parallel implementation in DelPhiPKa and can run a single job on up to 24 CPUs. The DelPhiPKa web server is available at http://compbio.clemson.edu/pka_webserver. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Investigation of the adsorption of water vapor and carbon dioxide by KA zeolite

    Khanitonov, V.P.; Shtein, A.S.

    1984-01-01

    According to the present data, KA zeolite, which can adsorb only water vapor, helium, and hydrogen, has the greatest selectivity in drying. The feasibility of using this zeolite in devices for selective drying of gases used in gas-analysis systems was studied. The results of the experiments were approximated by the thermal equation of the theory of bulk filling of micropores. The limiting value of the adsorption depends on the temperature, and it can be calculated according to the density of the adsorbed phase and the adsorption volume. The critical diameters of the water and carbon dioxide molecules are close to the dimensions of the KA-zeolite pores, something that determines the activated nature of the adsorption of these substances. Experiments on coadsorption of water vapor and carbon dioxide by a fixed bed of KA-zeolite under dynamic conditions showed that the adsorption of these substances has a frontal nature. The time of the protective action of the layer of zeolite during adsorption af water vapor exceeded by more than an order the time of the protective action during adsorption of carbon dioxide. The results showed that this adsorbent can be used for selective drying of gas mixtures containing carbon dioxide in batch-operation devices. Beforehand, the adsorbent should be regenerated with respect to moisture, and then it should be saturated with carbon dioxide by blowing the adsorbent with a gas mixture of the working composition until the equilibrium state is reached

  18. Developing hybrid approaches to predict pKa values of ionizable groups

    Witham, Shawn; Talley, Kemper; Wang, Lin; Zhang, Zhe; Sarkar, Subhra; Gao, Daquan; Yang, Wei

    2011-01-01

    Accurate predictions of pKa values of titratable groups require taking into account all relevant processes associated with the ionization/deionization. Frequently, however, the ionization does not involve significant structural changes and the dominating effects are purely electrostatic in origin allowing accurate predictions to be made based on the electrostatic energy difference between ionized and neutral forms alone using a static structure. On another hand, if the change of the charge state is accompanied by a structural reorganization of the target protein, then the relevant conformational changes have to be taken into account in the pKa calculations. Here we report a hybrid approach that first predicts the titratable groups, which ionization is expected to cause conformational changes, termed “problematic” residues, then applies a special protocol on them, while the rest of the pKa’s are predicted with rigid backbone approach as implemented in multi-conformation continuum electrostatics (MCCE) method. The backbone representative conformations for “problematic” groups are generated with either molecular dynamics simulations with charged and uncharged amino acid or with ab-initio local segment modeling. The corresponding ensembles are then used to calculate the pKa of the “problematic” residues and then the results are averaged. PMID:21744395

  19. Sequence preservation of osteocalcin protein and mitochondrial DNA in bison bones older than 55 ka

    Nielsen-Marsh, Christina M.; Ostrom, Peggy H.; Gandhi, Hasand; Shapiro, Beth; Cooper, Alan; Hauschka, Peter V.; Collins, Matthew J.

    2002-12-01

    We report the first complete sequences of the protein osteocalcin from small amounts (20 mg) of two bison bone (Bison priscus) dated to older than 55.6 ka and older than 58.9 ka. Osteocalcin was purified using new gravity columns (never exposed to protein) followed by microbore reversed-phase high-performance liquid chromatography. Sequencing of osteocalcin employed two methods of matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS): peptide mass mapping (PMM) and post-source decay (PSD). The PMM shows that ancient and modern bison osteocalcin have the same mass to charge (m/z) distribution, indicating an identical protein sequence and absence of diagenetic products. This was confirmed by PSD of the m/z 2066 tryptic peptide (residues 1 19); the mass spectra from ancient and modern peptides were identical. The 129 mass unit difference in the molecular ion between cow (Bos taurus) and bison is caused by a single amino-acid substitution between the taxa (Trp in cow is replaced by Gly in bison at residue 5). Bison mitochondrial control region DNA sequences were obtained from the older than 55.6 ka fossil. These results suggest that DNA and protein sequences can be used to directly investigate molecular phylogenies over a considerable time period, the absolute limit of which is yet to be determined.

  20. Computing pKa Values with a Mixing Hamiltonian Quantum Mechanical/Molecular Mechanical Approach.

    Liu, Yang; Fan, Xiaoli; Jin, Yingdi; Hu, Xiangqian; Hu, Hao

    2013-09-10

    Accurate computation of the pKa value of a compound in solution is important but challenging. Here, a new mixing quantum mechanical/molecular mechanical (QM/MM) Hamiltonian method is developed to simulate the free-energy change associated with the protonation/deprotonation processes in solution. The mixing Hamiltonian method is designed for efficient quantum mechanical free-energy simulations by alchemically varying the nuclear potential, i.e., the nuclear charge of the transforming nucleus. In pKa calculation, the charge on the proton is varied in fraction between 0 and 1, corresponding to the fully deprotonated and protonated states, respectively. Inspired by the mixing potential QM/MM free energy simulation method developed previously [H. Hu and W. T. Yang, J. Chem. Phys. 2005, 123, 041102], this method succeeds many advantages of a large class of λ-coupled free-energy simulation methods and the linear combination of atomic potential approach. Theory and technique details of this method, along with the calculation results of the pKa of methanol and methanethiol molecules in aqueous solution, are reported. The results show satisfactory agreement with the experimental data.

  1. The potentials for creating sustainable rural tourism in Bačka

    Stankov Uglješa

    2007-01-01

    Full Text Available Average rural household in Bačka mostly depend on agricultural activities. Modern society changes, especially changes in agriculture production imply need for diversification of business activities. Rural tourism can be important part of rural economy for some villages in Bačka. Fertile plain, Danube, Tisa and other smaller rivers, animals and games represent base of natural tourist attractions of rural tourism. However, main competitive advantages of Bačka are anthropogenic values. Traditional pannonian houses, baroques churches, numerous rural festivities, and "melting point" of different nationalities make good base for rural tourism development. Different combinations of rural attractions create several tourist experiences of this region: authentic tourist experience at "szalashes", particular tourist experience in villages, intensive tourist experience of rural events and manifestations, not authentic tourist experiences of pseudo rural attractions and complex tourist experience in rural areas. Regarding to emitive centers of rural tourist demand can be specified tree regions for development of rural tourism - region of Novi Sad, Subotica, and Sombor. Rural tourism can make a valuable contribution to rural economies, job creation, landscape conservation, retention of rural population, support to rural culture and tradition, nature conservation and other. At the same time, rural tourism is facing various limitations. With in this context, rural tourism planning has to include principles of sustainable development.

  2. A 230 ka record of glacial and interglacial events from Aurora Cave, Fiordland, New Zealand

    Williams, P.W.

    1996-01-01

    Caves overrun by glaciers are known to accumulate dateable evidence of past glacial and interglacial events. Results are reported from an investigation of Aurora Cave on the slopes above Lake Te Anau in Fiordland. The cave commenced to form before c. 230 ka B.P. Sequences of glaciofluvial sediments interbedded with speleothems are evidence of the number and timing of glacial advances and the status of intervals between them. Twenty-six uranium series dates on speleothems underpin a chronology of seven glacial advances in the last 230 ka, with the peak of the late Otira glaciation, Aurora 3 advance, at c. 19 ka B.P. With five advances in the Otiran, the last glaciation is more complex than previously recognised. Comparison of the record with that recorded offshore from DSDP Site 594 reveals little matching, but the correspondence of the Aurora sequence with that interpreted from other onshore deposits is more convincing. Glacial deposits on slopes above the cave for a further 660 m may be evidence of the 'missing' glacial events of the mid-early Pleistocene. (author). 44 refs., 12 figs., 5 tabs

  3. Results from the Cooler and Lead Tests

    Green, Michael A.

    2010-01-01

    The report presents the results of testing MICE spectrometer magnet current leads on a test apparatus that combines both the copper leads and the high temperature superconducting (HTS) leads with a single Cryomech PT415 cooler and liquid helium tank. The current is carried through the copper leads from 300 K to the top of the HTS leads. The current is then carried through the HTS leads to a feed-through from the vacuum space to the inside of a liquid helium tank. The experiment allows one to measure the performance of both cooler stages along with the performance of the leads. While the leads were powered we measured the voltage drops through the copper leads, through the HTS leads, through spliced to the feed-through, through the feed-through and through the low-temperature superconducting loop that connects one lead to the other. Measurements were made using the leads that were used in spectrometer magnet 1A and spectrometer magnet 2A. These are the same leads that were used for Superbend and Venus magnets at LBNL. The IL/A for these leads was 5.2 x 10 6 m -1 . The leads turned out to be too long. The same measurements were made using the leads that were installed in magnet 2B. The magnet 2B leads had an IL/A of 3.3 x 10 6 A m -1 . This report discusses the cooler performance and the measured electrical performance of the lead circuit that contains the copper leads and the superconducting leads. All of the HTS leads that were installed in magnet 2B were current tested using this apparatus.

  4. Defense Waste Processing Facility Canister Closure Weld Current Validation Testing

    Korinko, P. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Maxwell, D. N. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2018-01-29

    Two closure welds on filled Defense Waste Processing Facility (DWPF) canisters failed to be within the acceptance criteria in the DWPF operating procedure SW4-15.80-2.3 (1). In one case, the weld heat setting was inadvertently provided to the canister at the value used for test welds (i.e., 72%) and this oversight produced a weld at a current of nominally 210 kA compared to the operating procedure range (i.e., 82%) of 240 kA to 263 kA. The second weld appeared to experience an instrumentation and data acquisition upset. The current for this weld was reported as 191 kA. Review of the data from the Data Acquisition System (DAS) indicated that three of the four current legs were reading the expected values, approximately 62 kA each, and the fourth leg read zero current. Since there is no feasible way by further examination of the process data to ascertain if this weld was actually welded at either the target current or the lower current, a test plan was executed to provide assurance that these Nonconforming Welds (NCWs) meet the requirements for strength and leak tightness. Acceptance of the welds is based on evaluation of Test Nozzle Welds (TNW) made specifically for comparison. The TNW were nondestructively and destructively evaluated for plug height, heat tint, ultrasonic testing (UT) for bond length and ultrasonic volumetric examination for weld defects, burst pressure, fractography, and metallography. The testing was conducted in agreement with a Task Technical and Quality Assurance Plan (TTQAP) (2) and applicable procedures.

  5. Paleo-hydrological changes in the Chew Bahir area during the past 50 ka inferred from isotope signatures in aquatic microfossils

    Junginger, Annett

    2017-04-01

    A major challenge in paleo-anthropology is to understand the impact of climatic changes on human evolution. The Hominin Sites and Paleo-lakes Drilling Project (HSPDP) is currently meeting that challenge by providing records that cover the last 3.7 Ma of paleoenvironmental change all located in close proximity to key paleo-anthropological findings in East Africa. One of the cored climatic archives comes from the Chew Bahir basin in southern Ethiopia, where duplicate sediment cores provide valuable insights about East African environmental variability during the last 550 ka. The lake basins in the eastern branch of the East African Rift System today contain mainly shallow and alkaline lakes. However, paleo-shorelines in the form of wave cut notches, shell beds, and beach ridges are common morphological evidences for deep freshwater lakes that have filled the basins up to their overflow level during pronounced humid episodes, such as the African Humid Period (15-5 ka). Unfortunately, further back in time, many of those morphological features disappear due to erosion and the estimation of paleo-water depths depend merely on qualitative proxies from core analyses. We here present a method that shows high potential to translate qualitative proxy signals from sediment core analyses to quantitative climate signals in the Ethiopian Rift. The method aims at water level reconstruction in the Chew Bahir basin using strontium isotope ratios (87Sr/86Sr, SIR) in lacustrine microfossils. SIR reflect the lithology of the drained catchment. SIR have changed pronouncedly when higher elevated paleo-lakes Abaya, Chamo and Awassa were overflowing into paleo-lake Chew Bahir. This new method may help to quantify paleo-lake levels beyond the past 20 ka and may also detect migrational barriers or routes due to the occurrence of synchronous large, connected and deep paleo-lakes.

  6. Hydrological variability in the Northern Levant: a 250 ka multiproxy record from the Yammoûneh (Lebanon) sedimentary sequence

    Gasse, F.; Vidal, L.; Develle, A.-L.; van Campo, E.

    2011-11-01

    The Levant is a key region in terms of both long-term hydroclimate dynamics and human cultural evolution. Our understanding of the regional response to glacial-interglacial boundary conditions is limited by uncertainties in proxy-data interpretation and the lack of long-term records from different geographical settings. The present paper provides a 250 ka paleoenvironmental reconstruction based on a multi-proxy approach from northern Levant, derived from a 36 m lacustrine-palustrine sequence cored in the small intra-mountainous karstic Yammoûneh basin from northern Lebanon. We combined time series of sediment properties, paleovegetation, and carbonate oxygen isotopes (δc), to yield a comprehensive view of paleohydrologic-paleoclimatic fluctuations in the basin over the two last glacial-interglacial cycles. Integration of all available proxies shows that Interglacial maxima (early-mid MIS 7, MIS 5.5 and early MIS 1) experienced relatively high effective moisture, evidenced by the dominance of forested landscapes (although with different forest types) associated with authigenic carbonate sedimentation in a productive waterbody. Synchronous and steep δc increases can be reconciled with enhanced mean annual moisture when changes in seasonality are taken into account. During Glacials periods (MIS 2 and MIS 6), open vegetation tends to replace the forests, favouring local erosion and detrital sedimentation. However, all proxy data reveal an overall wetting during MIS 6, while a drying trend took place during MIS4-2, leading to extremely harsh LGM conditions possibly linked to water storage as ice in the surrounding highlands. Over the past 250 ka, the Yammoûneh record shows an overall decrease in local effective water, coincident with a weakening of seasonal insolation contrasts linked to the decreasing amplitude of the eccentricity cycle. The Yammoûneh record is roughly consistent with long-term climatic fluctuations in the northeastern Mediterranean region (except

  7. Hydrological variability in the Northern Levant: a 250 ka multiproxy record from the Yammoûneh (Lebanon sedimentary sequence

    F. Gasse

    2011-11-01

    Full Text Available The Levant is a key region in terms of both long-term hydroclimate dynamics and human cultural evolution. Our understanding of the regional response to glacial-interglacial boundary conditions is limited by uncertainties in proxy-data interpretation and the lack of long-term records from different geographical settings.

    The present paper provides a 250 ka paleoenvironmental reconstruction based on a multi-proxy approach from northern Levant, derived from a 36 m lacustrine-palustrine sequence cored in the small intra-mountainous karstic Yammoûneh basin from northern Lebanon. We combined time series of sediment properties, paleovegetation, and carbonate oxygen isotopes (δc, to yield a comprehensive view of paleohydrologic-paleoclimatic fluctuations in the basin over the two last glacial-interglacial cycles. Integration of all available proxies shows that Interglacial maxima (early-mid MIS 7, MIS 5.5 and early MIS 1 experienced relatively high effective moisture, evidenced by the dominance of forested landscapes (although with different forest types associated with authigenic carbonate sedimentation in a productive waterbody. Synchronous and steep δc increases can be reconciled with enhanced mean annual moisture when changes in seasonality are taken into account. During Glacials periods (MIS 2 and MIS 6, open vegetation tends to replace the forests, favouring local erosion and detrital sedimentation. However, all proxy data reveal an overall wetting during MIS 6, while a drying trend took place during MIS4-2, leading to extremely harsh LGM conditions possibly linked to water storage as ice in the surrounding highlands. Over the past 250 ka, the Yammoûneh record shows an overall decrease in local effective water, coincident with a weakening of seasonal insolation contrasts linked to the decreasing amplitude of the eccentricity cycle.

    The Yammoûneh record is roughly consistent with long-term climatic

  8. Weathering rind formation in buried terrace cobbles during periods of up to 300ka

    Yoshida, H.; Metcalfe, R.; Nishimoto, S.; Yamamoto, H.; Katsuta, N.

    2011-01-01

    Highlights: → Weathering rinds in sandstone and basalt cobbles buried for up to 300 ka have been investigated. → The aim was to determine the formation process and elemental mass balances during rind development. → Elemental mass balances across the rinds were determined by using open system mass balance (τ i,j ) calculations. → The formation rates are slower than the tropical areas due to the lower rainfall in the studied area. - Abstract: Weathering rinds formed in Mesozoic sandstone and basalt cobbles buried in terrace deposits for up to 300 ka have been investigated. The aim was to determine the formation process and elemental mass balances during rind development. The ages of terraces distributed in the western part of Fukui prefecture, central Japan have been determined as 50 ka, 120 ka and 300 ka based on a tephro-stratigraphic method. Detailed investigations across the weathering rinds, consisting of microscopic observations, porosity measurements, and mineralogical and geochemical analyses using X-ray diffractometry (XRD), X-ray fluorescence (XRF), secondary X-ray analytical microscopy (SXAM), scanning electron microanalyser (SEM) and electron probe microanalysis (EPMA) have been carried out. The results revealed that the Fe concentrations in the weathering rind of a basalt cobble slightly decreased from the cobble's surface (rim) towards the unweathered core. In contrast, in a sandstone cobble formed under the same environmental conditions over the same period of time there is an Fe-rich layer at some distance below the cobble's surface. Elemental mass balances across the rinds were determined by using open system mass balance (τ i,j ) calculations and show that the Fe was precipitated as Fe-oxyhydroxides in the basalt cobbles, although Fe was slightly removed from the rims. In sandstone cobbles, on the other hand, Fe migrated along a Fe concentration gradient by diffusion and precipitated as Fe-oxyhydroxide minerals to form the weathering rinds

  9. Palaeocirculation across New Zealand during the last glacial maximum at ˜21 ka

    Lorrey, Andrew M.; Vandergoes, Marcus; Almond, Peter; Renwick, James; Stephens, Tom; Bostock, Helen; Mackintosh, Andrew; Newnham, Rewi; Williams, Paul W.; Ackerley, Duncan; Neil, Helen; Fowler, Anthony M.

    2012-03-01

    What circulation pattern drove Southern Alps glacial advances at ˜21 ka? Late 20th century glacial advances in New Zealand are commonly attributed to a dual precipitation increase and cooler than normal temperatures associated with enhanced westerly flow that occur under synoptic pressure patterns termed 'zonal' regimes (Kidson, 2000). But was the circulation pattern that supported major Southern Alps glacial advances during the global LGM similar to the modern analog? Here, a Regional Climate Regime Classification (RCRC) time slice was used to infer past circulation for New Zealand during the LGM at ˜21 ka. Palaeoclimate information that supported the construction of the ˜21 ka time slice was derived from the NZ-INTIMATE Climate Event Stratigraphy (CES), one new Auckland maar proxy record, and additional low-resolution data sourced from the literature. The terrestrial evidence at ˜21 ka implicates several possibilities for past circulation, depending on how interpretations for some proxies are made. The interpretation considered most tenable for the LGM, based on the agreement between terrestrial evidence, marine reconstructions and palaeoclimate model results is an 'anticyclonic/zonal' circulation regime characterized by increased influences from blocking 'highs' over the South Island during winter and an increase in zonal and trough synoptic types (with southerly to westerly quarter wind flow) during summer. These seasonal circulation traits would have generated lower mean annual temperatures, cooler than normal summer temperatures, and overall lower mean annual precipitation for New Zealand (particularly in the western South Island) at ˜21 ka. The anticyclonic/zonal time slice reconstruction presented in this study has different spatial traits than the late 20th Century and the early Little Ice Age signatures, suggesting more than one type of regional circulation pattern can drive Southern Alps glacial activity. This finding lends support to the hypothesis

  10. Cataclysmic Rock Avalanche from El Capitan, Yosemite Valley, circa 3.6 ka

    Stock, G. M.

    2008-12-01

    El Capitan in Yosemite Valley is one of the largest and most iconic granite faces in the world. Despite glacially steepened walls exceeding 90 degrees, a historic database shows relatively few rock falls from El Capitan in the past 150 years. However, a massive bouldery deposit beneath the southeast face suggests an earlier rock avalanche of unusually large size. Spatial analysis of airborne LiDAR data indicate that the rock avalanche deposit has a volume of ~2.70 x 106 m3, a maximum thickness of 18 m, and a runout distance of 660 m, roughly twice the horizontal extent of the adjacent talus. The deposit is very coarse on its distal edge, with individual boulder volumes up to 2500 m3. Cosmogenic 10Be exposure dates from boulders distributed across the deposit confirm this interpretation. Four 10Be samples are tightly clustered between 3.5 and 3.8 ka, with a mean age of 3.6 +/- 0.6 ka. A fifth sample gives a much older age of 22.0 ka, but a glacier occupied Yosemite Valley at this time, prohibiting deposition; thus, the older age likely results from exposure on the cliff face prior to failure. The similarity of ages and overall morphology suggest that the entire deposit formed during a single event. The mean exposure age coincides with inferred Holocene rupture of the northern Owens Valley and/or White Mountain fault(s) between 3.3 and 3.8 ka (Lee et al., 2001; Bacon and Pezzopane, 2007). This time coincidence, combined with the fact that historic rupture of the Owens Valley fault in A.D. 1872 generated numerous large rock falls in Yosemite Valley, strongly suggests that the El Capitan rock avalanche was triggered by a seismic event along the eastern margin of the Sierra Nevada circa 3.6 ka. As there is not an obvious "scar" on the expansive southeast face, the exact source area of the rock avalanche is not yet known. Detrital apatite U-Th/(He) thermochronometry can determine the elevation(s) from which rock fall boulders originate, but significant inter-sample age

  11. Distribution of lead in teeth

    Fremlin, J H; Tanti-Wipawin, W [Birmingham Univ. (UK). Dept. of Physics

    1976-07-01

    There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an ..cap alpha.. emitter, half-life 8 d. These ..cap alpha.. particles can be recorded by a plastic solid-state track detector.

  12. Distribution of lead in teeth

    Fremlin, J.H.; Tanti-Wipawin, W.

    1976-01-01

    There is currently much concern with the amount of lead in the environment. Measurement of lead in teeth is being used to give information on the integrated uptake of lead by the individual over a period. The distribution of lead within individual teeth, is examined with the object of distinguishing lead deposited during formation or calcification from that taken up by the tooth over its working life after eruption. A tooth is sectioned and bombarded with 30-MeV ions of helium-3 from the Birmingham 1.52-m cyclotron, which produces polonium isotopes. The main useful activity is due to polonium-206, an α emitter, half-life 8 d. These α particles can be recorded by a plastic solid-state track detector. (U.K.)

  13. Ostaci srednjevjekovne utvrde Kaštel (Fenarlik u kartografskim izvorima XIX i XX vijeka : The remains of the fortress Kaštel (Fenarlik in cartographic sources of the 19th and 20th centuries

    Jusuf Topoljak

    2015-12-01

    Full Text Available Utvrda Kaštel (Fenarlik, locirana između Novog Travnika i Bugojna, vjerovatno je podignuta u razdoblju srednjeg vijeka, a u kartografskim izvorima se prvi put javlja tek 1883. godine. Geodetski planovi i karte 19. i 20. vijeka vjerodostojno dokumentuju propadanje ostataka tog utvrđenja, isprva ga jasno prikazujući kao ruševinu, dok se naposljetku sačuvao samo toponim Kaštel. Ovim radom autori su pokušali identifikovati i objediniti sve relevantne kartografske izvore na kojima je predočen lokalitet Kaštela, uz analizu načina topografisanja ostataka srednjevjekovne utvrde. : The fortress Kaštel (Fenarlik, located between Novi Travnik and Bugojno, probably was built in the period of middle ages. Concerning cartographic sources, it first appeared in 1883. Geodetic plans and maps from the 19th and 20th century credibly documented deterioration of the fortress remains. At first, it clearly displayed a ruin, while ultimately toponym Kaštel was the only preserved. Authors of this paper tried to identify and consolidate all relevant cartographic sources that represent the place Kaštel, together with the analysis of topographing the medieval fortresses.

  14. Direct-Current Forced Interruption and Breaking Performance of Spiral-Type Contacts in Aero Applications

    Wenlei Huo

    2017-05-01

    Full Text Available This paper analyses the transient characteristics and breaking performance of direct-current (DC forced-interruption vacuum interrupters in 270 V power-supply systems. Three stages are identified in forced interruption: the DC-arcing stage, current-commutation stage, and voltage-recovery stage. During the current-commutation stage, the reverse peak-current coefficient k, which is a key design factor, is used to calculate the rate of current at zero-crossing (di/dt. MATLAB/Simulink simulation models are established to obtain the transient characteristics influenced by the forced-commutation branch parameters and the coefficient k. To study the breaking performance of spiral-type contacts, experiments are conducted for different contact materials and arcing times for currents less than 3.5 kA. During the DC-arcing stage, a locally intensive burning arc is observed in the CuW80 contact; however, it is not observed in the CuCr50 contact. On examining the re-ignition interruption results of the CuW80 contact, the intensive burning arc is found to be positioned within a possible re-ignition region. When the arcing time is longer than 1 ms, the intensive burning arc occurs and affects the breaking performance of the spiral-type contacts. If the DC-arcing stage is prolonged, the total arcing energy increases, which leads to a lower breaking capacity.

  15. Lead (Pb) Air Pollution

    ... Regional Offices Labs and Research Centers Lead (Pb) Air Pollution Contact Us Share As a result of EPA's ... and protect aquatic and terrestrial ecosystems. Lead (Pb) Air Pollution Basic Information How does lead get in the ...

  16. 20180318 - Prediction Of pKa From Chemical Structure Using Free And Open-Source Tools (ACS Spring)

    The ionization state of a chemical, reflected in pKa values, affects lipophilicity, solubility, protein binding and the ability of a chemical to cross the plasma membrane. These properties govern the pharmacokinetic parameters such as absorption, distribution, metabolism, excreti...

  17. Dopingaine võib kätte saada ka vanaema retseptiga / Kristjan Port ; intervjueerinud Indrek Kuus

    Port, Kristjan, 1960-

    2011-01-01

    Intervjuu Tallinna Ülikooli terviseteaduste ja spordi instituudi direktori, SA Eesti Antidoping nõukogu liikme Kristjan Pordiga, kes tõdeb, et profispordi kõrval on dopingainetega muret ka harrastusspordis

  18. Berliini filmifestivalil näeb ka Peeter Simmi filmi "Head käed" / Triin Tael

    Tael, Triin

    2002-01-01

    Berliini 52. filmifestival algas eile sakslase Tom Tykweri mängufilmiga "Taevas". Esmakordselt on festivali "Panorama" kavas eesti mängufilm, milleks on Peeter Simmi "Head käed". Eesti filmid on esil ka festivali suurel filmiturul

  19. pKa prediction for acidic phosphorus-containing compounds using multiple linear regression with computational descriptors.

    Yu, Donghai; Du, Ruobing; Xiao, Ji-Chang

    2016-07-05

    Ninety-six acidic phosphorus-containing molecules with pKa 1.88 to 6.26 were collected and divided into training and test sets by random sampling. Structural parameters were obtained by density functional theory calculation of the molecules. The relationship between the experimental pKa values and structural parameters was obtained by multiple linear regression fitting for the training set, and tested with the test set; the R(2) values were 0.974 and 0.966 for the training and test sets, respectively. This regression equation, which quantitatively describes the influence of structural parameters on pKa , and can be used to predict pKa values of similar structures, is significant for the design of new acidic phosphorus-containing extractants. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  20. Enroni krahh võib hakata mõjutama ka Eesti ettevõtteid / Gert D. Hankewitz

    Hankewitz, Gert D.

    2006-01-01

    USA energiafirma Enron finantspettus võib hakata läbi koostööpartnerite, kellele hakkavad kehtima karmimad raamatupidamisreeglid, mõjutama ka Eesti firmasid. Vt. samas: Akt karmistab reegleid; Hansapangale tooks akt lisakulutusi

  1. High-Efficiency, Ka-band Solid-State Power Amplifier Utilizing GaN Technology, Phase I

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop an efficient, solid-state power amplifier (SSPA), operating at Ka-band frequencies, for high data rate, long range space...

  2. High-Efficiency, Ka-Band Solid-State Power Amplifier Utilizing GaN Technology, Phase II

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a high-efficiency, solid-state power amplifier (SSPA), operating at Ka-band frequencies, for high data rate, long range space...

  3. Enne võõrandamist uppunud auriku eest saab ka hüvitust / Hille Tänavsuu

    Tänavsuu, Hille, 1941-2014

    2006-01-01

    Tallinna linnavalitsuse otsusest kompenseerida kuue, 1940. aasta oktoobris õigusvastaselt võõrandatud, aurulaeva mõttelisi osi. Laevadega seotud probleemist ka laiemalt ning laevade saatusest. Lisatud: mis on õigusvastaselt võõrandatud vara

  4. Miniaturized UHF, S-, and Ka-band RF MEMS Filters for Small Form Factor, High Performance EVA Radio, Phase II

    National Aeronautics and Space Administration — In Phase II of this SBIR, Harmonic Devices (HDI) proposes to develop miniaturized MEMS filters at UHF, S-band and Ka-band to address the requirements of NASA's...

  5. Variation of paleo-productivity and terrigenous input in the eastern Arabian Sea during the past 100 ka

    Ishfaq, A.M.; Pattan, J.N.; Matta, V.M.; Banakar, V.K.

    A 4.1m long sediment core from the eastern Arabian Sea is studied using multiple geochemical proxies to understand the variation of productivity and terrigenous matter supply during the past 100 ka. The temporal variation in element concentration...

  6. Cell cycle-dependent regulation of kainate-induced inward currents in microglia

    Yamada, Jun; Sawada, Makoto; Nakanishi, Hiroshi

    2006-01-01

    Microglia are reported to have α-amino-hydroxy-5-methyl-isoxazole-4-propionate/kainate (KA) types. However, only small population of primary cultured rat microglia (approximately 20%) responded to KA. In the present study, we have attempted to elucidate the regulatory mechanism of responsiveness to KA in GMIR1 rat microglial cell line. When the GMIR1 cells were plated at a low density in the presence of granulocyte macrophage colony-stimulating factor, the proliferation rate increased and reached the peak after 2 days in culture and then gradually decreased because of density-dependent inhibition. At cell proliferation stage, approximately 80% of the GMIR1 cells exhibited glutamate (Glu)- and KA-induced inward currents at cell proliferation stage, whereas only 22.5% of the cells showed responsiveness to Glu and KA at cell quiescent stage. Furthermore, the mean amplitudes of inward currents induced by Glu and KA at cell proliferation stage (13.8 ± 3.0 and 8.4 ± 0.6 pA) were significantly larger than those obtained at cell quiescent stage (4.7 ± 0.8 and 6.2 ± 1.2 pA). In the GMIR1 cells, KA-induced inward currents were markedly inhibited by (RS)-3-(2-carboxybenzyl) willardiine (UBP296), a selective antagonist for KA receptors. The KA-responsive cells also responded to (RS)-2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl) propanoic acid (ATPA), a selective agonist for GluR5, in both GMIR1 cells and primary cultured rat microglia. Furthermore, mRNA levels of the KA receptor subunits, GluR5 and GluR6, at the cell proliferation stage were significantly higher than those at the cell quiescent stage. Furthermore, the immunoreactivity for GluR6/7 was found to increase in activated microglia in the post-ischemic hippocampus. These results strongly suggest that microglia have functional KA receptors mainly consisting of GluR5 and GluR6, and the expression levels of these subunits are closely regulated by the cell cycle mechanism

  7. The 13 ka Pelée-Type Dome Collapse at Nevado de Toluca Volcano, México.

    D'Antonio, M.; Capra, L.; Sarocchi, D.; Bellotti, F.

    2007-05-01

    The Nevado de Toluca is an active volcano located in the central sector of the Trans-Mexican Volcanic Belt, 80 km southwest of Mexico City. Activity at this andesitic to dacitic stratovolcano began ca. 2.6 Ma ago. During the last 42 ka, the volcano has been characterized by different eruptive styles, including five dome collapses dated at 37, 32, 28, 26, and 13 ka and five Plinian eruptions at 42 ka, 36 ka, 21.7 ka, 12.1 ka and 10.5 ka. The 13 ka dome collapse is the youngest event of this type, and originated a 0.11 km3 block-and-ash flow deposit on the north-eastern sector of the volcano. The deposit consists of two facies: channel-like, 10 m thick, monolitologic, that is composed of up to five units, with decimetric dacitic clasts set in a sandy matrix; and a lateral facies that consists of a gray, sandy horizon, up to 4 m thick, with a 30 cm-thick surge layer at the base. The main component is a dacitic lava, with different degree of vesciculation, with mineral association of Pl-Hbl-Opx. Plagioclases show two different textures: in equilibrium, with normal zoning (core = An37-64.3, rim = An30.7-45.8) or with spongy cellular texture with inverse zoning (core = An38-43.5, rim = An45-51.2). Hornblende is normally light green, barren of oxidation. The rock matrix contains up to 53 perc. of glass with abundant microlites, indicating over-pressure on the crystallizing magma and a rapid expulsion. All these stratigraphic and petrographic features indicate that the dome was quickly extruded on the summit of the volcano, probably triggered by a magma mixing process, and its collapse was accompanied by an explosive component, being classified as a Pelée-type event.

  8. Preliminary Analysis of X-Band and Ka-Band Radar for Use in the Detection of Icing Conditions Aloft

    Reehorst, Andrew L.; Koenig, George G.

    2004-01-01

    NASA and the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) have an on-going activity to develop remote sensing technologies for the detection and measurement of icing conditions aloft. Radar has been identified as a strong tool for this work. However, since the remote detection of icing conditions with the intent to identify areas of icing hazard is a new and evolving capability, there are no set requirements for radar sensitivity. This work is an initial attempt to quantify, through analysis, the sensitivity requirements for an icing remote sensing radar. The primary radar of interest for cloud measurements is Ka-band, however, since NASA is currently using an X-band unit, this frequency is also examined. Several aspects of radar signal analysis were examined. Cloud reflectivity was calculated for several forms of cloud using two different techniques. The Air Force Geophysical Laboratory (AFGL) cloud models, with different drop spectra represented by a modified gamma distribution, were utilized to examine several categories of cloud formation. Also a fundamental methods approach was used to allow manipulation of the cloud droplet size spectra. And an analytical icing radar simulator was developed to examine the complete radar system response to a configurable multi-layer cloud environment. Also discussed is the NASA vertical pointing X-band radar. The radar and its data system are described, and several summer weather events are reviewed.

  9. Deglacial to Holocene history of ice-sheet retreat and bottom current strength on the western Barents Sea shelf

    Lantzsch, Hendrik; Hanebuth, Till J. J.; Horry, Jan; Grave, Marina; Rebesco, Michele; Schwenk, Tilmann

    2017-10-01

    High-resolution sediment echosounder data combined with radiocarbon-dated sediment cores allowed us to reconstruct the Late Quaternary stratigraphic architecture of the Kveithola Trough and surrounding Spitsbergenbanken. The deposits display the successive deglacial retreat of the Svalbard-Barents Sea Ice Sheet. Basal subglacial till indicates that the grounded ice sheet covered both bank and trough during the Late Weichselian. A glaciomarine blanket inside the trough coinciding with laminated plumites on the bank formed during the initial ice-melting phase from at least 16.1 to 13.5 cal ka BP in close proximity to the ice margin. After the establishment of open-marine conditions at around 13.5 cal ka BP, a sediment drift developed in the confined setting of the Kveithola Trough, contemporary with crudely laminated mud, an overlying lag deposit, and modern bioclastic-rich sand on Spitsbergenbanken. The Kveithola Drift shows a remarkable grain-size coarsening from the moat towards the southern flank of the trough. This trend contradicts the concept of a separated drift (which would imply coarser grain sizes in proximity of the moat) and indicates that the southern bank is the main sediment source for the coarse material building up the Kveithola Drift. This depocenter represents, therefore, a yet undescribed combination of off-bank wedge and confined drift. Although the deposits inside Kveithola Trough and on Spitsbergenbanken display different depocenter geometries, time-equivalent grain-size changes imply a region-wide sediment-dynamic connection. We thus relate a phase of coarsest sediment supply (8.8-6.3 cal ka BP) to an increase in bottom current strength, which might be related to a stronger Atlantic Water inflow from the Southeast across the bank leading to winnowing and off-bank export of sandy sediments.

  10. Estimated pKa values for the environmentally relevant C1 through C8 perfluorinated sulfonic acid isomers.

    Rayne, Sierra; Forest, Kaya

    2016-10-14

    In order to estimate isomer-specific acidity constants (pKa) for the perfluorinated sulfonic acid (PFSA) environmental contaminants, the parameterization method 6 (PM6) pKa prediction method was extensively validated against a wide range of carbon oxyacids and related sulfonic/sulfinic acids. Excellent pKa prediction performance was observed for the carbon oxyacids using the PM6 method, but this approach was found to have a severe positive bias for sulfonic/sulfinic acids. To overcome this obstacle, a correlation was developed between non-adjusted PM6 pKa values and the corresponding experimentally obtained/estimated acidity constants for a range of representative alkyl, aryl and halogen-substituted sulfonic acids. Application of this correction to the PM6 values allows for extension of this computational method to a new acid functional group. When used to estimate isomer-specific pKa values for the C1 through C8 PFSAs, the modified PM6 approach suggests an adjusted pKa range from -5.3 to -9.0, indicating that all members of this class of well-known environmental contaminants will be effectively completely dissociated in aquatic systems.

  11. p Ka determinations of xanthene derivates in aqueous solutions by multivariate analysis applied to UV-Vis spectrophotometric data

    Batistela, Vagner Roberto; Pellosi, Diogo Silva; de Souza, Franciane Dutra; da Costa, Willian Ferreira; de Oliveira Santin, Silvana Maria; de Souza, Vagner Roberto; Caetano, Wilker; de Oliveira, Hueder Paulo Moisés; Scarminio, Ieda Spacino; Hioka, Noboru

    2011-09-01

    Xanthenes form to an important class of dyes which are widely used. Most of them present three acid-base groups: two phenolic sites and one carboxylic site. Therefore, the p Ka determination and the attribution of each group to the corresponding p Ka value is a very important feature. Attempts to obtain reliable p Ka through the potentiometry titration and the electronic absorption spectrophotometry using the first and second orders derivative failed. Due to the close p Ka values allied to strong UV-Vis spectral overlap, multivariate analysis, a powerful chemometric method, is applied in this work. The determination was performed for eosin Y, erythrosin B, and bengal rose B, and also for other synthesized derivatives such as 2-(3,6-dihydroxy-9-acridinyl) benzoic acid, 2,4,5,7-tetranitrofluorescein, eosin methyl ester, and erythrosin methyl ester in water. These last two compounds (esters) permitted to attribute the p Ka of the phenolic group, which is not easily recognizable for some investigated dyes. Besides the p Ka determination, the chemometry allowed for estimating the electronic spectrum of some prevalent protolytic species and the substituents effects evaluation.

  12. Fast wave current drive in DIII-D

    Petty, C.C.; Callis, R.W.; Chiu, S.C.; deGrassie, J.S.; Forest, C.B.; Freeman, R.L.; Gohil, P.; Harvey, R.W.; Ikezi, H.; Lin-Liu, Y.-R.

    1995-02-01

    The non-inductive current drive from fast Alfven waves launched by a directional four-element antenna was measured in the DIII-D tokamak. The fast wave frequency (60 MHz) was eight times the deuterium cyclotron frequency at the plasma center. An array of rf pickup loops at several locations around the torus was used to verify the directivity of the four-element antenna. Complete non-inductive current drive was achieved using a combination of fast wave current drive (FWCD) and electron cyclotron current drive (ECCD) in discharges for which the total plasma current was inductively ramped down from 400 to 170 kA. For discharges with steady plasma current, up to 110 kA of FWCD was inferred from an analysis of the loop voltage, with a maximum non-inductive current (FWCD, ECCD, and bootstrap) of 195 out of 310 kA. The FWCD efficiency increased linearly with central electron temperature. For low current discharges, the FWCD efficiency was degraded due to incomplete fast wave damping. The experimental FWCD was found to agree with predictions from the CURRAY ray-tracing code only when a parasitic loss of 4% per pass was included in the modeling along with multiple pass damping

  13. Is cardiac resynchronization therapy an option in heart failure patients with preserved ejection fraction? Justification for the ongoing KaRen project.

    Donal, Erwan; Lund, Lars; Linde, Cecilia; Daubert, Jean-Claude

    2010-01-01

    The relevance of electrical and mechanical dyssynchrony has been demonstrated in heart failure with reduced ejection fraction. Preserved ejection fraction is present in as many as 50% of patients with chronic heart failure. Recent small studies suggest that both electrical and mechanical left ventricular dyssynchrony are sometimes present in patients with heart failure and preserved ejection fraction (HFPEF). These data remain controversial and a robust validation of this hypothesis has to be achieved. In the present paper, we review in detail the concepts and try to justify the ongoing KaRen registry. This is a prospective, multicentre, international, observational study to characterize the prevalence of electrical or mechanical dyssynchrony in HFPEF and the resultant effect on prognosis. Patients are enrolled currently at the time of an acute congestive episode. The diagnosis of HFPEF is made according to clinical data, natriuretic peptides and echocardiography for the measurement of ejection fraction. Once stabilized, patients return for a hospital check-up. They undergo clinical and biological evaluation, electrocardiography and Doppler echocardiography. Thereafter, patients are followed every six months, for at least 18 months for mortality, and heart failure-related and non-cardiovascular hospitalizations. KaRen aims to characterize electrical and mechanical dyssynchrony and to assess its prognostic impact in HFPEF. The results may improve our understanding of HFPEF and generate answers to the question of whether or not dyssynchrony could be a target for cardiac resynchronization therapy in HFPEF. Copyright 2010 Elsevier Masson SAS. All rights reserved.

  14. Detailed design of a 13 kA 13 kV dc solid-state turn-off switch. [Revision

    Praeg, W.F.

    1985-01-01

    An experimental facility for the study of electromagnetic effects in the First Wall-Blanket-Shield (FWBS) systems of fusion reactors has been constructed at Argonne National Laboratory (ANL). In a test volume of 0.76 m 3 , a vertical, pulsed 5 kG dipole field (B dot less than or equal to 320 kGs -1 ) is perpendicular to a 10 kG solenoid field. Power supplies of 2.75 MW at 550 V dc and 5.5 MW at 550 V dc and a solid-state switch rated at 13 kA and 13 kV (169 MW) control the pulsed magnetic fields. The total stored energy in the coils is 2.6 MJ. This paper describes the design and construction features of the solid-state switching circuit which turns off a dc current of 13 kA in approximately 82 μs and holds off voltages of less than or equal to 13 kV. 14 figs

  15. Lead - nutritional considerations

    ... billion people had toxic (poisonous) blood lead levels. Food Sources Lead can be found in canned goods if there is lead solder in the ... to bottled water for drinking and cooking. Avoid canned goods from foreign ... cans goes into effect. If imported wine containers have a lead foil ...

  16. Electric fields in plasmas under pulsed currents

    Tsigutkin, K.; Doron, R.; Stambulchik, E.; Bernshtam, V.; Maron, Y.; Fruchtman, A.; Commisso, R. J.

    2007-01-01

    Electric fields in a plasma that conducts a high-current pulse are measured as a function of time and space. The experiment is performed using a coaxial configuration, in which a current rising to 160 kA in 100 ns is conducted through a plasma that prefills the region between two coaxial electrodes. The electric field is determined using laser spectroscopy and line-shape analysis. Plasma doping allows for three-dimensional spatially resolved measurements. The measured peak magnitude and propagation velocity of the electric field is found to match those of the Hall electric field, inferred from the magnetic-field front propagation measured previously

  17. Optimization of crude oil degradation by Dietzia cinnamea KA1, capable of biosurfactant production.

    Kavynifard, Amirarsalan; Ebrahimipour, Gholamhossein; Ghasempour, Alireza

    2016-05-01

    The aim of this study was isolation and characterization of a crude oil degrader and biosurfactant-producing bacterium, along with optimization of conditions for crude oil degradation. Among 11 isolates, 5 were able to emulsify crude oil in Minimal Salt Medium (MSM) among which one isolate, named KA1, showed the highest potency for growth rate and biodegradation. The isolate was identified as Dietzia cinnamea KA1 using morphological and biochemical characteristics and 16S rRNA gene sequencing. The optimal conditions were 510 mM NaCl, pH 9.0, 35 °C, and minimal requirement of 46.5 mM NH4 Cl and 2.10 mM NaH2 PO4 . Gravimetric test and Gas chromatography-Mass spectroscopy technique (GC-MS) showed that Dietzia cinnamea KA1 was able to utilize and degrade 95.7% of the crude oil after 5 days, under the optimal conditions. The isolate was able to grow and produce biosurfactant when cultured in MSM supplemented with crude oil, glycerol or whey as the sole carbon sources, but bacterial growth was occurred using molasses with no biosurfactant production. This is the first report of biosurfactant production by D. cinnamea using crude oil, glycerol and whey and the first study to report a species of Dietzia degrading a wide range of hydrocarbons in a short time. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Evidence for an Elevated Aspartate pKa in the Active Site of Human Aromatase*

    Di Nardo, Giovanna; Breitner, Maximilian; Bandino, Andrea; Ghosh, Debashis; Jennings, Gareth K.; Hackett, John C.; Gilardi, Gianfranco

    2015-01-01

    Aromatase (CYP19A1), the enzyme that converts androgens to estrogens, is of significant mechanistic and therapeutic interest. Crystal structures and computational studies of this enzyme shed light on the critical role of Asp309 in substrate binding and catalysis. These studies predicted an elevated pKa for Asp309 and proposed that protonation of this residue was required for function. In this study, UV-visible absorption, circular dichroism, resonance Raman spectroscopy, and enzyme kinetics were used to study the impact of pH on aromatase structure and androstenedione binding. Spectroscopic studies demonstrate that androstenedione binding is pH-dependent, whereas, in contrast, the D309N mutant retains its ability to bind to androstenedione across the entire pH range studied. Neither pH nor mutation perturbed the secondary structure or heme environment. The origin of the observed pH dependence was further narrowed to the protonation equilibria of Asp309 with a parallel set of spectroscopic studies using exemestane and anastrozole. Because exemestane interacts with Asp309 based on its co-crystal structure with the enzyme, its binding is pH-dependent. Aromatase binding to anastrozole is pH-independent, consistent with the hypothesis that this ligand exploits a distinct set of interactions in the active site. In summary, we assign the apparent pKa of 8.2 observed for androstenedione binding to the side chain of Asp309. To our knowledge, this work represents the first experimental assignment of a pKa value to a residue in a cytochrome P450. This value is in agreement with theoretical calculations (7.7–8.1) despite the reliance of the computational methods on the conformational snapshots provided by crystal structures. PMID:25425647

  19. Transmission characteristic of graphene/TiO2 paper measured at Ka-band

    Agusu, La; Mitsudo, Seitaro; Ahmad, La Ode; Herdianto, Fujii, Yutaka; Ishikawa, Yuya; Furuya, Takahashi; Ramadhan, La Ode Ahmad Nur

    2017-01-01

    The commercial telecommunication system in future would explore the electromagnetic spectrum with higher frequency than used now, because it requires higher speed of transmission data. Using the millimeter waves (mmW) with frequency ranging from 30 to 300 GHz, such requirement could be fulfilled. The upcoming 5G cellular technology is expected to use frequency 30 GHz or higher. Then materials with a specific characteristic at the mmW range are interesting to be explored and investigated. Here, we report the synthesis process of graphene/TiO2 deposited on paper and their transmission characteristics to the electromagnetic energy at frequency 27-40 GHz (Ka-Band). The reduced graphene oxide (rGO) was synthesized by a modified Hummers method with introduction of microwave irradiation in the process. rGO and TiO2 were mixed in ethanol solution and deposited on the paper by a spraying technique. Transmission coefficient of electromagnetic wave energy at Ka-Band was measured by using the millimeter vector network analyzer. Conductivity of rGO is 1.89 Scm-1 and for the graphene/TiO2 with TiO2 content is up to 50%, conductivity is down to Scm-1 Graphene/TiO2 layer with thickness of 60).lm and TiO2 loading up to 25% can has the transmission coefficient of -4 dB at the middle frequency of 31 GHz and bandwidth of 2.2 GHz. This can be useful as the electromagnetic interference shielding material at Ka-band.

  20. Improved Culture Medium (TiKa) for Mycobacterium avium Subspecies Paratuberculosis (MAP) Matches qPCR Sensitivity and Reveals Significant Proportions of Non-viable MAP in Lymphoid Tissue of Vaccinated MAP Challenged Animals

    Bull, Tim J.; Munshil, Tulika; Melvang, Heidi Mikkelsen

    2017-01-01

    The quantitative detection of viable pathogen load is an important tool in determining the degree of infection in animals and contamination of foodstuffs. Current conventional culture methods are limited in their ability to determine these levels in Mycobacterium avium subspecies paratuberculosis......Ka culture equates well with qPCR and provides important evidence that accuracy in estimating viable MAP load using DNA tests alone may vary significantly between samples of mucosal and lymphatic origin....... (MAP) due to slow growth, clumping and low recoverability issues. The principle goal of this study was to evaluate a novel culturing process (TiKa) with unique ability to stimulate MAP growth from low sample loads and dilutions. We demonstrate it was able to stimulate a mean 29-fold increase...

  1. Ka eakad tahavad ja suudavad töötada / Kadi Pärnits

    Pärnits, Kadi, 1965-

    2005-01-01

    Ilmunud ka: Sakala 4. mai lk. 2, Lääne Elu 5. mai, lk. 2, Koit 5. mai, lk. 6, Videvik 5. mai lk. 2, Harjumaa 6. mai, lk. 2, Põhjarannik 6. mai, lk. 2, Severnoje Poberezhje 6. mai lk. 2, Hiiu Leht 3. juuni lk. 2, Valgamaalane 9. juuni lk. 2, Pärnu Postimees 5. juuli lk. 15, Vooremaa 26. juuli lk. 2. Sotsiaaldemokraatide algatusest kehtivat töölepinguseadust muuta ja võtta tööandjatelt õigus vabaneda eakast töötajast kohe, kui viimane saab 65 aastaseks

  2. MARKETINŠKA STRATEGIJA ZA SPLETNO TRGOVINO KUPONI.ENAA.COM

    Marzidošek, Dean

    2016-01-01

    Marketinška strategija za spletne trgovine je precej drugačna od klasične marketinške strategije. Seveda upošteva enake zakonitosti, vendar so v večini primerov klasični oglaševalski kanali, kot so na primer televizija, radio, tisk in podobno, popolnoma odsotni. Na drugi strani jih nadomeščajo digitalni kanali v popolnosti, ki se jim je treba tudi bolj podrobno posvetiti v spletni strategiji. Prednost digitalnih kanalov je v zelo dobri in hitri merljivosti rezultatov, dostopnost takšnih oglaš...

  3. An occurrence of approx. 74 ka Youngest Toba tephra from the western continental margin of India

    Pattan, J.N.; Shane, P.; Pearce, N.J.G.; Banakar, V.K.; Parthiban, G.

    . Navalgund and Dr M. S. Narayanan du r- ing the course of this work. Useful discussions with Dr P. S. Desai and Dr A. Sarkar are also thankfully acknow l edged. Received 28 July 2000; revised accepted 3 January 2001 An occurrence of ~ 7 4 ka.... The occurrence of Y TT in the west, north - west, south - west and recently north - east in the South China Sea Basin 17 , suggests wind direction du r ing YTT was not in one way. YTT occurred between oxygen isotope stage 5a and 4, a period of ice growth...

  4. Health of primary teachers in Obalno-kraška region

    Lavrič, Katja

    2013-01-01

    The purpose of the dissertation was to evaluate the health of elementary school teachers teaching in the southwestern part of Slovenia, in the so-called Obalno-kraška region. The main goals were to determine how often do these teachers engage in physical activity, how frequently are they absent from work due to health problems, how often do they feel tense, under stress or under severe pressure and how do they deal with it, how many of them smoke or live in a smoking environment, what is thei...

  5. Ka Band Phase Locked Loop Oscillator Dielectric Resonator Oscillator for Satellite EHF Band Receiver

    S. Coco

    2008-01-01

    Full Text Available This paper describes the design and fabrication of a Ka Band PLL DRO having a fundamental oscillation frequency of 19.250 GHz, used as local oscillator in the low-noise block of a down converter (LNB for an EHF band receiver. Apposite circuital models have been created to describe the behaviour of the dielectric resonator and of the active component used in the oscillator core. The DRO characterization and measurements have shown very good agreement with simulation results. A good phase noise performance is obtained by using a very high Q dielectric resonator.

  6. Proposal for a Joint NASA/KSAT Ka-band RF Propagation Terminal at Svalbard, Norway

    Volosin, Jeffrey; Acosta, Roberto; Nessel, James; McCarthy, Kevin; Caroglanian, Armen

    2010-01-01

    This slide presentation discusses the placement of a Ka-band RF Propagation Terminal at Svalbard, Norway. The Near Earth Network (NEN) station would be managed by Kongsberg Satellite Services (KSAT) and would benefit NASA and KSAT. There are details of the proposed NASA/KSAT campaign, and the responsibilities each would agree to. There are several reasons for the placement, a primary reason is comparison with the Alaska site, Based on climatological similarities/differences with Alaska, Svalbard site expected to have good radiometer/beacon agreement approximately 99% of time.

  7. Pension tuleb maal tasuta koju ka tulevikus / Siim-Valmar Kiisler

    Kiisler, Siim, 1965-

    2008-01-01

    Regionaalminister Siim-Valmar Kiisleri sõnul toetas riigikogu sotsiaalkomisjon tema ettepanekut ning otsustas kirjutada eelnõusse sisse sätte, et hajaasustusega piirkondades ning asulates, kus pangateenused pole kättesaadavad, jääb pensionide ning hüvitiste kojukanne edaspidigi tasuta. Ilmunud ka: Harju Elu 17. okt. lk. 2, Vooremaa 16. okt. lk. 2; Harju Elu 17. okt. lk. 2; Kuulutaja 17. okt. lk. 4; Võrumaa Teataja 18. okt. lk. 2; Meie Maa 16. okt. lk. 2; Koit 21. okt. lk. 6; Sakala 22. okt. lk. 2; Oma Saar 23. okt. lk. 5

  8. Advanced mobile satellite communications using COMETS satellite in MM-wave and Ka-band

    Ohmori, Shingo; Isobe, Shunkichi; Takeuchi, Makoto; Naito, Hideyuki

    1993-01-01

    Early in the 21st century, the demand for personal communications using mobile, hand-held, and VSAT terminals will rapidly increase. In a future system, many different types of services should be provided with one-hop connection. The Communications Research Laboratory (CRL) has studied a future advanced mobile satellite communications system using millimeter wave and Ka band. In 1990, CRL started the Communications and Broadcasting Engineering Test Satellite (COMETS) project. The satellite has been developed in conjunction with NASDA and will be launched in 1997. This paper describes the COMETS payload configuration and the experimental system for the advanced mobile communications mission.

  9. "Parim" on subjektiivne, aga kõhutundest ka ei piisa / Inga Kuusik

    Kuusik, Inga, 1961-

    2007-01-01

    Ilmunud ka: Finansovõi Menedzhment : infovõpusk nr. 13 apr. lk. 6-7. Saku Õlletehase uus finantsjuht oma tööst tubakatootja Imperial Tobacco Grupi Kesk-Aasia regiooni finantsdirektorina Kõrgõzstanis, Saku Õlletehase kapitali struktuurist, finantsdirektori rollist ettevõttes ja tööjõu värbamisest Saku Õlletehases. Lisad: Saku Õlletehas 2006: mõõdukas käibe-, aga suur kasumikasv; Tabel: Saku Õlletehase dividendimaksed 1997-2007

  10. The Development and Demonstration of a 360m/10 kA HTS DC Power Cable

    Xiao, Liye

    With the quick development of renewable energy, it is expected that the electric power from renewable energy would be the dominant one for the future power grid. Due to the specialty of the renewable energy, the HVDC power transmission would be very useful for the transmission of electric power from renewable energy. DC power cable made of High Tc Superconductor (HTS) would be a possible alternative for the construction of HVDC power transmission system. In this chapter, we report the development and demonstration of a 360 m/10 kA HTS DC power cable and the test results.

  11. Analysis of Standards Efficiency in Digital Television Via Satellite at Ku and Ka Bands

    Landeros-Ayala Salvador

    2013-06-01

    Full Text Available In this paper, an analysis on the main technical features of digital television standards for satellite transmission is carried out. Based on simulations and link budgets, the standard with the best operational performance is defined, based on simulations and link budget analysis, as well as a comparative efficiency analysis is conducted for the Ku and Ka bands for both transparent and regenerative transponders in terms of power, bandwidth, information rate and link margin, including clear sky, uplink rain, downlink rain and rain in both.

  12. Mapping return currents in laser-generated Z-pinch plasmas using proton deflectometry

    Manuel, M. J.-E.; Sinenian, N.; Seguin, F. H.; Li, C. K.; Frenje, J. A.; Rinderknecht, H. G.; Casey, D. T.; Zylstra, A. B.; Petrasso, R. D.; Beg, F. N.

    2012-01-01

    Dynamic return currents and electromagnetic field structure in laser-generated Z-pinch plasmas have been measured using proton deflectometry. Experiments were modeled to accurately interpret deflections observed in proton radiographs. Current flow is shown to begin on axis and migrate outwards with the expanding coronal plasma. Magnetic field strengths of ∼1 T are generated by currents that increase from ∼2 kA to ∼7 kA over the course of the laser pulse. Proton deflectometry has been demonstrated to be a practical alternative to other magnetic field diagnostics for these types of plasmas.

  13. Use of microsecond current prepulse for dramatic improvements of wire array Z-pinch implosion

    Calamy, H.; Lassalle, F.; Loyen, A.; Zucchini, F.; Chittenden, J. P.; Hamann, F.; Maury, P.; Georges, A.; Bedoch, J. P.; Morell, A.

    2008-01-01

    The Sphinx machine [F. Lassalle et al., 'Status on the SPHINX machine based on the 1microsecond LTD technology'] based on microsecond linear transformer driver (LTD) technology is used to implode an aluminium wire array with an outer diameter up to 140 mm and maximum current from 3.5 to 5 MA. 700 to 800 ns implosion Z-pinch experiments are performed on this driver essentially with aluminium. Best results obtained before the improvement described in this paper were 1-3 TW radial total power, 100-300 kJ total yield, and 20-30 kJ energy above 1 keV. An auxiliary generator was added to the Sphinx machine in order to allow a multi microsecond current to be injected through the wire array load before the start of the main current. Amplitude and duration of this current prepulse are adjustable, with maxima ∼10 kA and 50 μs. This prepulse dramatically changes the ablation phase leading to an improvement of the axial homogeneity of both the implosion and the final radiating column. Total power was multiplied by a factor of 6, total yield by a factor of 2.5 with a reproducible behavior. This paper presents experimental results, magnetohydrodynamic simulations, and analysis of the effect of such a long current prepulse

  14. Valobran Kaše: tijek i način izgradnje, primijenjene antičke tehnike gradnje u renesansi

    Željko Peković

    2017-05-01

    Full Text Available Kaše breakwater, doubtless, is a remarkable monument of Renaissance civil engineering, masterly designed and executed by Paskoje Miličević. This boldly conceived project witnessed many problems from the very beginning of its construction. Serious damages due to heavy storms happened to be so severe at times that, as evidenced by archival data, the breakwater faced collapse, which called for emergency repairs. It was built in four stages between 1486 and 1514, in dry docks. The fi rst, smaller part was built in 1486, while the other, somewhat bigger, in 1487, to be joined in 1498, and expanded to the north in 1514. The breakwater was built in a submerged and later dried out dock (kašeta. The latter was framed with sheet piles (a layer of joint wooden posts, while the bottom consisted of two layers of bars upon which the breakwater is bedded. The breakwater was built from large stone blocks, joined by hydraulic mortar composed of red clay and lime, with no pozzolanic additives. Stone blocks were fi rst connected with iron and later bronze joints and clamps covered with lead. The central part of the breakwater is ‘cemented’ with lime mortar, red clay and sand, with an addition of crushed stone. Some ancient construction techniques, reinvented in the Renaissance, were applied in this building project. The reason why the breakwater still stands in place lies in two major facts: the use of large and high quality stone blocks and their connection, and in the section below the waterline, with metal joints and clamps covered with lead.

  15. An estimation of tropospheric corrections using GPS and synoptic data: Improving Urmia Lake water level time series from Jason-2 and SARAL/AltiKa satellite altimetry

    Arabsahebi, Reza; Voosoghi, Behzad; Tourian, Mohammad J.

    2018-05-01

    Tropospheric correction is one of the most important corrections in satellite altimetry measurements. Tropospheric wet and dry path delays have strong dependence on temperature, pressure and humidity. Tropospheric layer has particularly high variability over coastal regions due to humidity, wind and temperature gradients. Depending on the extent of water body and wind conditions over an inland water, Wet Tropospheric Correction (WTC) is within the ranges from a few centimeters to tens of centimeters. Therefore, an extra care is needed to estimate tropospheric corrections on the altimetric measurements over inland waters. This study assesses the role of tropospheric correction on the altimetric measurements over the Urmia Lake in Iran. For this purpose, four types of tropospheric corrections have been used: (i) microwave radiometer (MWR) observations, (ii) tropospheric corrections computed from meteorological models, (iii) GPS observations and (iv) synoptic station data. They have been applied to Jason-2 track no. 133 and SARAL/AltiKa track no. 741 and 356 corresponding to 117-153 and the 23-34 cycles, respectively. In addition, the corresponding measurements of PISTACH and PEACHI, include new retracking method and an innovative wet tropospheric correction, have also been used. Our results show that GPS observation leads to the most accurate tropospheric correction. The results obtained from the PISTACH and PEACHI projects confirm those obtained with the standard SGDR, i.e., the role of GPS in improving the tropospheric corrections. It is inferred that the MWR data from Jason-2 mission is appropriate for the tropospheric corrections, however the SARAL/AltiKa one is not proper because Jason-2 possesses an enhanced WTC near the coast. Furthermore, virtual stations are defined for assessment of the results in terms of time series of Water Level Height (WLH). The results show that GPS tropospheric corrections lead to the most accurate WLH estimation for the selected

  16. Lead inclusions in aluminium

    Johnson, E.; Johansen, A.; Sarholt-Kristensen, L.; Andersen, H.H.; Grabaek, L.; Bohr, J.

    1990-01-01

    Ion implantation at room temperature of lead into aluminum leads to spontaneous phase separation and formation of lead precipitates growing topotactically with the matrix. Unlike the highly pressurized (∼ 1-5 GPa) solid inclusions formed after noble gas implantations, the pressure in the lead precipitates is found to be less than 0.12 GPa. Recently the authors have observed the result that the lead inclusions in aluminum exhibit both superheating and supercooling. In this paper they review and elaborate on these results. Small implantation-induced lead precipitates embedded in an aluminum matrix were studied by x-ray diffraction

  17. Experimental determination of net protein charge and A(tot) and K(a) of nonvolatile buffers in human plasma.

    Staempfli, Henry R; Constable, Peter D

    2003-08-01

    The mechanism for an acid-base disturbance can be determined by using the strong ion approach, which requires species-specific values for the total concentration of plasma nonvolatile buffers (Atot) and the effective dissociation constant for plasma weak acids (Ka). The aim of this study was to experimentally determine Atot and Ka values for human plasma by using in vitro CO2 tonometry. Plasma Pco2 was systematically varied from 25 to 145 Torr at 37 degrees C, thereby altering plasma pH over the physiological range of 6.90-7.55, and plasma pH, Pco2, and concentrations of quantitatively important strong ions (Na+, K+, Ca2+, Mg2+, Cl-, lactate) and buffer ions (total protein, albumin, phosphate) were measured. Strong ion difference was estimated, and nonlinear regression was used to calculate Atot and Ka from the measured pH and Pco2 and estimated strong ion difference; the Atot and Ka values were then validated by using a published data set (Figge J, Rossing TH, and Fencl V, J Lab Clin Med 117: 453-467, 1991). The values (mean +/- SD) were as follows: Atot = 17.2 +/- 3.5 mmol/l (equivalent to 0.224 mmol/g of protein or 0.378 mmol/g of albumin); Ka = 0.80 +/- 0.60 x 10-7; negative log of Ka = 7.10. Mean estimates were obtained for strong ion difference (37 meq/l) and net protein charge (13+.0 meq/l). The experimentally determined values for Atot, Ka, and net protein charge should facilitate the diagnosis and treatment of acid-base disturbances in critically ill humans.

  18. The role of the northward-directed (sub)surface limb of the Atlantic Meridional Overturning Circulation during the 8.2 ka Event

    Tegzes, A. D.; Jansen, E.; Telford, R. J.

    2014-02-01

    The so-called "8.2 ka Event" has been widely regarded as a major climate perturbation over the Holocene. It is most readily identifiable in the oxygen-isotope records from Greenland ice cores as an approximately 160 yr-long cold interval between 8250-8090 yr BP. The prevailing view has been that the cooling over Greenland, and potentially over the northern North Atlantic at least, was triggered by the catastrophic final drainage of the Agassiz-Ojibway proglacial lake as part of the remnant Laurentide Ice Sheet collapsed over Hudson Bay at around 8420 ± 80 yr BP. The consequent freshening of surface waters in the northern North Atlantic Ocean and the Nordic Seas resulted in weaker overturning, hence reduced northward heat transport. Here we present proxy records from site JM97-MD95-2011 on the mid-Norwegian Margin indicating a (sharp) decline in the strength of the eastern branch of the Atlantic Inflow into the Nordic Seas immediately following a uniquely large drop in (sub)surface ocean temperatures coeval with the lake outbursts. We propose that the final drainage of Lake Agassiz-Ojibway was accompanied by a major iceberg discharge from Hudson Bay, which resulted in the cooling of the northward-directed northern Gulf Stream-North Atlantic Drift-Norwegian Atlantic Current system. Since our current-strength proxy records from the mid-Norwegian Margin do not evidence an exceptionally strong reduction in the main branch of the Atlantic Inflow into the Nordic Seas at the time, we argue that a chilled northward-directed (sub)surface-current system and an already colder background climate state could be the main factors responsible for the 8.2 ka climate perturbation.

  19. Unraveling the sequence and structure of the protein osteocalcin from a 42 ka fossil horse

    Ostrom, Peggy H.; Gandhi, Hasand; Strahler, John R.; Walker, Angela K.; Andrews, Philip C.; Leykam, Joseph; Stafford, Thomas W.; Kelly, Robert L.; Walker, Danny N.; Buckley, Mike; Humpula, James

    2006-04-01

    We report the first complete amino acid sequence and evidence of secondary structure for osteocalcin from a temperate fossil. The osteocalcin derives from a 42 ka equid bone excavated from Juniper Cave, Wyoming. Results were determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-MS) and Edman sequencing with independent confirmation of the sequence in two laboratories. The ancient sequence was compared to that of three modern taxa: horse ( Equus caballus), zebra ( Equus grevyi), and donkey ( Equus asinus). Although there was no difference in sequence among modern taxa, MALDI-MS and Edman sequencing show that residues 48 and 49 of our modern horse are Thr, Ala rather than Pro, Val as previously reported (Carstanjen B., Wattiez, R., Armory, H., Lepage, O.M., Remy, B., 2002. Isolation and characterization of equine osteocalcin. Ann. Med. Vet.146(1), 31-38). MALDI-MS and Edman sequencing data indicate that the osteocalcin sequence of the 42 ka fossil is similar to that of modern horse. Previously inaccessible structural attributes for ancient osteocalcin were observed. Glu 39 rather than Gln 39 is consistent with deamidation, a process known to occur during fossilization and aging. Two post-translational modifications were documented: Hyp 9 and a disulfide bridge. The latter suggests at least partial retention of secondary structure. As has been done for ancient DNA research, we recommend standards for preparation and criteria for authenticating results of ancient protein sequencing.

  20. Ferroelectric switch for a high-power Ka-band active pulse compressor

    Hirshfield, Jay L. [Omega-P, Inc., New Haven, CT (United States)

    2013-12-18

    Results are presented for design of a high-power microwave switch for operation at 34.3 GHz, intended for use in an active RF pulse compressor. The active element in the switch is a ring of ferroelectric material, whose dielectric constant can be rapidly changed by application of a high-voltage pulse. As envisioned, two of these switches would be built into a pair of delay lines, as in SLED-II at SLAC, so as to allow 30-MW μs-length Ka-band pulses to be compressed in time by a factor-of-9 and multiplied in amplitude to generate 200 MW peak power pulses. Such high-power pulses could be used for testing and evaluation of high-gradient mm-wave accelerator structures, for example. Evaluation of the switch design was carried out with an X-band (11.43 GHz) prototype, built to incorporate all the features required for the Ka-band version.