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Sample records for castor tokamak

  1. Hard X-ray studies on the Castor tokamak

    International Nuclear Information System (INIS)

    Mlynar, J.

    1990-04-01

    The electron runaway processes in tokamaks are discussed with regard to hard X radiation measurements. The origin and confinement of runaway electrons, their bremsstrahlung spectra and the influence of lower hybrid current drive on the distribution of high-energy electrons are analyzed for the case of the Castor tokamak. The hard X-ray spectrometer designed for the Castor tokamak is also described and preliminary qualitative results of hard X-ray measurements are presented. The first series of integral measurements made it possible to map the azimuthal dependence of the hard X radiation

  2. Control of plasma position in the CASTOR tokamak

    International Nuclear Information System (INIS)

    Valovic, M.

    1988-11-01

    A simple servo-system designed for plasma position control in the CASTOR tokamak is described. Both radial and vertical plasma displacements were minimized using two servo-loops consisting of detection coils, a conventional electric controller and an amplifier operated as an unipolar voltage-controlled current source. To ensure the optimum conditions in the start-up phase of the discharge, currents in the servo-systems were externally preprogrammed. The prescribed plasma position was maintained with the accuracy of 3 mm. The feedback control improves plasma parameters, e.g. it removes the positional disruption at the end of the tokamak discharge. (J.U.). 4 figs., 3 refs

  3. Test of the quasi-optical grill for lower hybrid current drive on the CASTOR tokamak

    International Nuclear Information System (INIS)

    Klima, R.; Pavlo, P.; Preinhaelter, J.; Stoeckel, J.; Zacek, F.; Jakubka, K.; Kletecka, P.; Kryska, L.

    1994-03-01

    Feasibility studies of a new diffraction structure for launching lower hybrid waves into a tokamak plasma - of the microwave quasi-optical grill - are reported. The main parameters of the grill designed for the CASTOR tokamak are summarized, and results of preliminary radiation pattern measurements of a non-optimized model antenna are presented. The influence of a relatively great curvature of the plasma surface in the CASTOR tokamak is discussed and the ray tracing of the launched lower-hybrid wave in the actual CASTOR plasma is shown. Finally, the results of probe measurements of the CASTOR plasma core are given. (J.U.) 17 figs., 9 refs

  4. Microwave correllation reflectometry for tokamak CASTOR

    Czech Academy of Sciences Publication Activity Database

    Nanobashvili, S.; Žáček, František; Zajac, Jaromír

    2005-01-01

    Roč. 55, č. 6 (2005), s. 701-719 ISSN 0011-4626 R&D Projects: GA AV ČR IAA1043101 Grant - others:GA EU(EU) INTAS ´2001 1B-2056 Institutional research plan: CEZ:AV0Z20430508 Keywords : microwaves * tokamak * plasma * turbulence * reflectometry Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.360, year: 2005

  5. Magnetic measurements using array of integrated Hall sensors on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Ďuran, Ivan; Hronová-Bilyková, Olena; Stöckel, Jan; Sentkerestiová, J.; Havlíček, Josef

    2008-01-01

    Roč. 79, č. 10 (2008), 10F123-10F123 ISSN 0034-6748. [Topical Conference on High-Temperature Plasma Diagnostics/17th./. Albuquerque, 11.05.2008-15.05.2008] R&D Projects: GA MPO 2A-1TP1/101 Institutional research plan: CEZ:AV0Z20430508 Keywords : Galvanomagnetic Sensor * Fusion Reactor * Magnetic Diagnostics * CASTOR tokamak Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.738, year: 2008

  6. JOINT EXPERIMENTS ON SMALL TOKAMAKS: EDGE PLASMA STUDIES ON CASTOR

    Czech Academy of Sciences Publication Activity Database

    Van Oost, G.; Berta, M.; Brotánková, Jana; Dejarnac, Renaud; Del Bosco, E.; Dufková, Edita; Ďuran, Ivan; Gryaznevich, M.P.; Horáček, Jan; Hron, Martin; Malaquias, A.; Mank, G.; Peleman, P.; Sentkerestiová, Jana; Stöckel, Jan; Weinzettl, Vladimír; Zoletnik, S.; Tál, B.; Ferrera, J.; Fonseca, A.; Hegazy, H.; Kuznetsov, Y.; Ossyannikov, A.; Singh, A.; Sokholov, M.; Talebitaher, A.

    2007-01-01

    Roč. 47, č. 5 (2007), s. 378-386 ISSN 0029-5515 R&D Projects: GA AV ČR KJB100430504 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * edge plasma * turbulence * Langmuir probe * plasma radiation * Hall probe Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.278, year: 2007

  7. RELAXATION PHENOMENA DURING EDGE BIASING EXPERIMENTS IN THE CASTOR TOKAMAK

    Czech Academy of Sciences Publication Activity Database

    Spolaore, M.; Martines, E.; Brotánková, Jana; Stöckel, Jan; Adámek, Jiří; Dufková, Edita; Ďuran, Ivan; Hron, Martin; Weinzettl, Vladimír; Peleman, P.; Van Oost, G.; Devynck, P.; Figueiredo, H.; Kirnev, G.

    2005-01-01

    Roč. 55, č. 12 (2005), s. 1597-1606 ISSN 0011-4626. [Electric Fields, Structures and Relaxation in Edge Plasmas,. Tarragona, 3.7.2005-4.7.2005] R&D Projects: GA ČR GA202/03/0786 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * edge biasing * relaxation * ExB flow Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.360, year: 2005

  8. Advanced probes for edge plasma diagnostics on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Stöckel, Jan; Adámek, Jiří; Balan, P.; Hronová-Bilyková, Olena; Brotánková, Jana; Dejarnac, Renaud; Devynck, P.; Ďuran, Ivan; Gunn, J. P.; Hron, Martin; Horáček, Jan; Ionita, C.; Kocan, M.; Martines, E.; Pánek, Radomír; Peleman, P.; Schrittwieser, R.; Van Oost, G.; Žáček, František

    2006-01-01

    Roč. 63, č. 0 (2006), 012001-012002 E-ISSN 1742-6596. [SECOND INTERNATIONAL WORKSHOP AND SUMMER SCHOOL ON PLASMA PHYSICS. Kiten, 03.07.2006-09.07.2006] R&D Projects: GA AV ČR KJB100430504 Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma * tokamak * electric probe s * diagnostics Subject RIV: BL - Plasma and Gas Discharge Physics

  9. Measurement of Safety Factor Using Hall Probes on CASTOR Tokamak

    Czech Academy of Sciences Publication Activity Database

    Kovařík, Karel; Ďuran, Ivan; Bolshakova, I.; Holyaka, R.; Erashok, V.

    2006-01-01

    Roč. 56, suppl.B (2006), s. 104-110 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/22nd./. Praha, 26.6.2006-29.6.2006] R&D Projects: GA AV ČR(CZ) KJB100430504 Institutional research plan: CEZ:AV0Z20430508 Keywords : Plasma * tokamak * safety factor * hall probe Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.568, year: 2006

  10. Edge Plasma Physics and Relevant Diagnostics on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Stöckel, Jan; Devynck, P.; Gunn, J.; Martines, E.; Bonhomme, G.; Van Oost, G.; Hron, Martin; Ďuran, Ivan; Pánek, Radomír; Stejskal, Pavel; Adámek, Jiří

    2004-01-01

    Roč. 3, - (2004), s. 1-6 ISSN 1433-5581. [First Cairo Conference on Plasma Physics & Applications. Cairo, 11.10.2003-15.10.2003] R&D Projects: GA ČR GA202/03/0786; GA ČR GP202/03/P062 Keywords : tokamak * edge plasma * probe diagnostics * biasing * turbulence * polarization Subject RIV: BL - Plasma and Gas Discharge Physics

  11. Toroidal electric field in front of the lower hybrid grill of the castor tokamak

    International Nuclear Information System (INIS)

    Zacek, F.; Petrzilka, V.; Devynck, P.; Goniche, M.

    2003-01-01

    A small tokamak Castor (R/a = 0.4/0.85 m) with low plasma energy density and short pulses (20 ms) offers a unique possibility to carry out probe measurements in front of the grill antenna and as a consequence to provide direct information about the local electric fields in this region. For measurements of the toroidal electrical field, a small double probe with 2 tips separated by 3.5 mm in the toroidal direction has been used. The tips are oriented in the radial direction. The probe is radially movable in front of the central grill waveguide. Cross-correlations and FFT (fast Fourier transform) analysis of the measured V fl signals are given together with an attempt to investigate characteristics of toroidal electric field E tor (up to 500 kHz), derived from V fl measured by 2 toroidally separated tips

  12. Comparative measurements of the plasma potential with the ball-pen and emissive probes on the CASTOR tokamak

    International Nuclear Information System (INIS)

    Adamek, J.; Stoeckel, J.; Duran, I.; Hron, M.; Panek, R.; Tichy, M.; Schrittwieser, R.; Ionita, C.; Balan, P.; Martines, E.; Van Oost, G.

    2005-01-01

    A novel approach to the direct measurement of the plasma potential in magnetized plasma, using the so-called 'ball-pen probe', was recently tested in the CASTOR tokamak. Comparison with the standard technique of plasma potential measurement using the emissive probe is reported. It is found that the plasma potential determined by the emissive probe is systematically lower than that measured by the ball-pen probe. The difference is of the order of kT e /e. A possible reason of this difference is the space charge occurring in the proximity of the emissive probe. (author)

  13. Measurement of electron temperature and density by Thomson scattering diagnostic on the Tokamak CASTOR

    Czech Academy of Sciences Publication Activity Database

    Brotánková, Jana; Plíšek, Pavel; Žáček, František

    2002-01-01

    Roč. 52, supplement D (2002), s. 51-58 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/20th./. Prague, 10.06.2002-13.06.2002] Institutional research plan: CEZ:AV0Z2043910 Keywords : tokamak, Thomson scattering, electron temperature Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.311, year: 2002

  14. Advanced Probe Measurements of Electron Energy Distribution Functions in CASTOR Tokamak Plasma

    Czech Academy of Sciences Publication Activity Database

    Popov, T.; Stöckel, Jan; Dejarnac, Renaud; Dimitrova, M.; Ivanova, P.; Naydenova, Tsv.

    2006-01-01

    Roč. 63, bez (2006), 012002-012003 E-ISSN 1742-6596. [SECOND INTERNATIONAL WORKSHOP AND SUMMER SCHOOL ON PLASMA PHYSICS. Kiten, 03.07.2006-09.07.2006] Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma * tokamak Subject RIV: BL - Plasma and Gas Discharge Physics

  15. Dynamics of the edge transport barrier at plasma biasing on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Stöckel, Jan; Spolaore, M.; Peleman, P.; Brotánková, Jana; Horáček, Jan; Dejarnac, Renaud; Devynck, P.; Ďuran, Ivan; Gunn, J. P.; Hron, Martin; Kocan, M.; Martines, E.; Pánek, Radomír; Sharma, A.; Van Oost, G.

    2006-01-01

    Roč. 12, č. 6 (2006), s. 19-23 ISSN 1562-6016. [International Conference on Plasma Physics and Technology/11th./. Alushta, 11.9.2006-16.9.2006] Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * plasma * transport barrier * relaxations Subject RIV: BL - Plasma and Gas Discharge Physics http:// vant .kipt.kharkov.ua/TABFRAME.html

  16. Spatially resolved characterization of electrostatic fluctuations in the scrape-off layer of the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Devynck, P.; Bonhomme, G.; Martines, E.; Stöckel, Jan; Van Oost, G.; Voitsekhovitch, I.; Adámek, Jiří; Azeroual, A.; Doveil, F.; Ďuran, Ivan; Gravier, E.; Gunn, J.; Hron, Martin

    2005-01-01

    Roč. 47, č. 2 (2005), s. 269-280 ISSN 0741-3335 R&D Projects: GA ČR GA202/03/0786 Grant - others:GA - INTAS 2001 2056 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * plasma * turbulence Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.902, year: 2005

  17. Relaxation phenomena induced by edge biasing experiments in the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Spolaore, M.; Martines, E.; Brotánková, Jana; Stöckel, Jan; Adámek, Jiří; Dufková, Edita; Ďuran, Ivan; Hron, Martin; Weinzettl, Vladimír; Peleman, P.; Van Oost, G.; Devynck, P.; Figueiredo, H.; Kirnev, G.

    2005-01-01

    Roč. 55, č. 12 (2005), s. 1597-1606 ISSN 0011-4626. [Workshop " Eletric Fields, Structures and Relaxation in Edge Plasmas/8th./. Tarragona, 3.72005-4.7.2005] R&D Projects: GA ČR GA202/03/0786 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * edge biasing * relaxation * E x B flow Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.360, year: 2005

  18. Comparative measurements of plasma position using coils, hall probes, and bolometers on CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Sentkerestiová, Jana; Ďuran, Ivan; Dufková, Edita; Weinzettl, Vladimír

    2006-01-01

    Roč. 56, suppl.B (2006), s. 138-144 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/22nd./. Praha, 26.6.2006-29.6.2006] R&D Projects: GA AV ČR KJB100430504 Institutional research plan: CEZ:AV0Z20430508 Keywords : Hall probes * plasma position * plasma * tokamak Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.568, year: 2006

  19. The role of radial electric fields in tokamaks TEXTOR-94, CASTOR, and T-10

    Czech Academy of Sciences Publication Activity Database

    Van Oost, G.; Gunn, J. P.; Melnikov, A.; Stöckel, Jan; Tendler, M.

    2001-01-01

    Roč. 51, č. 10 (2001), s. 957-975 ISSN 0011-4626. [Europhysics Workshop on The Role Electric Fields in Plasma Confinement and Exhaust/4th./. Funchal, Madeira, 24.06.2001-25.06.2001] Institutional research plan: CEZ:AV0Z2043910 Keywords : electric fields, tokamak Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.345, year: 2001

  20. Measurement of Sheared Flows in the Edge Plasma of the CASTOR Tokamak

    Czech Academy of Sciences Publication Activity Database

    Brotánková, Jana; Stöckel, Jan; Horáček, Jan; Seidl, Jakub; Ďuran, Ivan; Hron, Martin; Van Oost, G.

    2009-01-01

    Roč. 35, č. 11 (2009), s. 980-986 ISSN 1063-780X. [IAEA Technical Meeting on Research Using Small Fusion Devices/18th./. Alushta (Krym), 25.09. 2008 -27.09. 2008 ] Institutional research plan: CEZ:AV0Z20430508 Keywords : Tokamak * probe diagnostics * sheared flows * edge plasma * turbulence Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.584, year: 2009 http://www.springerlink.com/content/u571504gmq118314/

  1. Relaxation phenomena induced by edge biasing experiments in the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Spolaore, M.; Martines, E.; Brotánková, Jana; Stöckel, Jan; Adámek, Jiří; Dufková, Edita; Ďuran, Ivan; Hron, Martin; Weinzettl, Vladimír; Peleman, P.; Van Oost, G.; Devynck, P.; Figueiredo, H.; Kirnev, G.

    2005-01-01

    Roč. 55, č. 12 (2005), s. 1597-1606 ISSN 0011-4626. [Workshop on the Electric Fields, Structures, and Relaxation in Edge Plasmas/8th./. Tarragona, 3.7.2005-4.4.2005] R&D Projects: GA ČR(CZ) GA202/03/0789 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * edge biasing * relaxation * E x B flow Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.360, year: 2005 http://www.lib.cas.cz/casopisy/cz/Czechoslovak_Journal_of_Physics.htm

  2. Comparative measurements of the plasma potential with the ball-pen and emissive probes on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Adámek, Jiří; Stöckel, Jan; Hron, Martin; Ďuran, Ivan; Pánek, Radomír; Tichý, M.; Schrittwieser, R.; Ionita, C.; Balan, P.; Martines, E.; Van Oost, G.

    2005-01-01

    Roč. 55, č. 3 (2005), s. 235-242 ISSN 0011-4626 R&D Projects: GA ČR GA202/03/0786 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * edge plasma * plasma potential * Langmuir probe Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.360, year: 2005

  3. Decay of enhanced density and damping of plasma flows after the electrode biasing terminaton on the CASTOR tokamak

    Czech Academy of Sciences Publication Activity Database

    Hron, Martin; Ďuran, Ivan; Stöckel, Jan; Hidalgo, C.

    2004-01-01

    Roč. 54, suppl. C (2004), C22-C27 ISSN 0011-4626. [Symposium on Plasma Physics and Technology /21st/. Praha, 14.06.2004-17.06.2004] R&D Projects: GA ČR GA202/03/0786 Institutional research plan: CEZ:AV0Z2043910 Keywords : tokamak, edge plasma, polarization Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.292, year: 2004

  4. Tokamak

    International Nuclear Information System (INIS)

    Meglicki, Z.

    1995-01-01

    We describe in detail the implementation of a weighted differences code, which is used to simulate a tokamak using the Maschke-Perrin solution as an initial condition. The document covers the mainlines of the program and the most important problem-specific functions used in the initialization, static tests, and dynamic evolution of the system. The mathematics of the Maschke-Perrin solution is discussed in parallel with its realisation within the code. The results of static and dynamic tests are presented in sections discussing their implementation.The code can also be obtained by ftp -anonymous from cisr.anu.edu.au Directory /pub/papers/meglicki/src/tokamak. This code is copyrighted. (author). 13 refs

  5. ECRH on CASTOR

    Czech Academy of Sciences Publication Activity Database

    Preinhaelter, Josef; Žáček, František; Irzak, M. A.; Vahala, L.; Vahala, G.

    2000-01-01

    Roč. 50, S 3 (2000), s. 51-56 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/19th./. Prague, 06.06.2000-09.06.2000] R&D Projects: GA ČR GA202/00/1215; GA ČR GA202/97/0778 Institutional research plan: CEZ:AV0Z2043910 Keywords : plasma * tokamak * CASTOR Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.298, year: 2000

  6. Physicochemical characteristics of castor oil from local wild castor ...

    African Journals Online (AJOL)

    Physicochemical characteristics of castor oil from seeds of the local wild castor plant (Ricinus communis) found in Ghana were determined to evaluate its suitability for exploitation for industrial purposes. The castor seeds were found to be rich in oil, containing 57 per cent castor oil of which 37 per cent was easily expressed ...

  7. The CASTOR initiative

    Energy Technology Data Exchange (ETDEWEB)

    Le Thiez, Pierre [GEOGREEN (France)

    2008-07-15

    In this paper it is spoken over the CASTOR project, which has 31 partners of 12 European countries. Also it is spoken on the strategy for the CO{sub 2} reduction in Europe; what on the capture and post-combustion has been done, and what as far as geologic CO{sub 2} storage has been accomplished. [Spanish] En esta ponencia se habla sobre el proyecto Castor, el cual cuenta con 31 socios de 12 paises europeos. Tambien se habla sobre la estrategia para la reduccion de CO{sub 2} en Europa; lo que se ha hecho en cuanto a captura post-combustion y lo que se ha hecho para el almacenamiento geologico de CO{sub 2}.

  8. The CASTOR shower library

    International Nuclear Information System (INIS)

    Mundim Filho, Luiz Martins; Carvalho, Wagner de Paula

    2012-01-01

    Full text: CASTOR (Centaur And Strange Object Research) is an electromagnetic (EM) and hadronic (HAD) calorimeter, based on tungsten and quartz plates, operating in the CMS Detector (Compact Muon Solenoid) at LHC. The calorimeter detects Cerenkov radiation and is positioned around the beam pipe in the very forward region of CMS (at 14.38 m from the interaction point), covering the pseudo-rapidity range between -6.6 ≤ η≤-5.1 . It is longitudinally segmented into 14 sections, 2 for the EM and 12 for the HAD parts and is 16-fold azimuthally symmetric around the beam pipe. A Shower Library is needed for CASTOR Monte Carlo simulation, as the full simulation of showers takes a long time and the high multiplicity of particles in the forward region makes this simulation very time consuming. The Shower Library is used as a look-up table in the form of a ROOT file, so that when a simulated particle enters the detector with a certain energy and direction, characterized by the azimuthal angle φ and the pseudo-rapidity η, instead of making the full simulation of the shower in CASTOR, it is substituted by one already stored in the Shower Library. Showers corresponding to two types of particles are included in the Shower Library: electrons (or photons) and charged pions. The software implemented to make the Shower Library is described, as well as the validation of this library and timing studies. This package has been developed in the context of the official software of the CMS Collaboration, CMSSW. (author)

  9. Continuous tokamaks

    International Nuclear Information System (INIS)

    Peng, Y.K.M.

    1978-04-01

    A tokamak configuration is proposed that permits the rapid replacement of a plasma discharge in a ''burn'' chamber by another one in a time scale much shorter than the elementary thermal time constant of the chamber first wall. With respect to the chamber, the effective duty cycle factor can thus be made arbitrarily close to unity minimizing the cyclic thermal stress in the first wall. At least one plasma discharge always exists in the new tokamak configuration, hence, a continuous tokamak. By incorporating adiabatic toroidal compression, configurations of continuous tokamak compressors are introduced. To operate continuous tokamaks, it is necessary to introduce the concept of mixed poloidal field coils, which spatially groups all the poloidal field coils into three sets, all contributing simultaneously to inducing the plasma current and maintaining the proper plasma shape and position. Preliminary numerical calculations of axisymmetric MHD equilibria in continuous tokamaks indicate the feasibility of their continued plasma operation. Advanced concepts of continuous tokamaks to reduce the topological complexity and to allow the burn plasma aspect ratio to decrease for increased beta are then suggested

  10. Induced mutations in castor

    International Nuclear Information System (INIS)

    Ganesan, K.; Javad Hussain, H.S.; Vindhiyavarman, P.

    2001-01-01

    Castor (Ricinus communis L.) is an important oilseed crop in India. To create variability mutations were induced in two cultivars 'TMV5' (maturing in 130-140 days) and 'CO1' (perennial type). Gamma rays and diethyl sulphate and ethidium bromide were used for seed treatment. Ten doses, from 100 to 1000 Gy were employed. For chemical mutagenesis five concentrations of mutagenes from 10 to 50 mM were tried. No economic mutants could be isolated after treatment with the chemical mutagens. The following economic mutants were identified in the dose 300 Gy of gamma rays. Annual types from perennial CO 1 castor CO 1 is a perennial variety (8-10 years) with bold seeds (100 seed weight 90 g) and high oil content (57%). Twenty-one lines were isolated with annual types (160-180 days) with high yield potential as well as bold seeds and high oil content. These mutants, identified in M 3 generation were bred true in subsequent generations up to M 8 generation. Critical evaluation of the mutants in yield evaluation trials is in progress

  11. Research using small tokamaks

    International Nuclear Information System (INIS)

    1991-05-01

    The technical reports in this document were presented at the IAEA Technical Committee Meeting ''Research on Small Tokamaks'', September 1990, in three sessions, viz., (1) Plasma Modes, Control, and Internal Phenomena, (2) Edge Phenomena, and (3) Advanced Configurations and New Facilities. In Section (1) experiments at controlling low mode number modes, feedback control using external coils, lower-hybrid current drive for the stabilization of sawtooth activity and continuous (1,1) mode, and unmodulated and fast modulated ECRH mode stabilization experiments were reported, as well as the relation to disruptions and transport of low m,n modes and magnetic island growth; static magnetic perturbations by helical windings causing mode locking and sawtooth suppression; island widths and frequency of the m=2 tearing mode; ultra-fast cooling due to pellet injection; and, finally, some papers on advanced diagnostics, i.e., lithium-beam activated charge-exchange spectroscopy, and detection through laser scattering of discrete Alfven waves. In Section (2), experimental edge physics results from a number of machines were presented (positive biasing on HYBTOK II enhancing the radial electric field and improving confinement; lower hybrid current drive on CASTOR improving global particle confinement, good current drive efficiency in HT-6B showing stabilization of sawteeth and Mirnov oscillations), as well as diagnostic developments (multi-chord time resolved soft and ultra-soft X-ray plasma radiation detection on MT-1; measurements on electron capture cross sections in multi-charged ion-atom collisions; development of a diagnostic neutral beam on Phaedrus-T). Theoretical papers discussed the influence of sheared flow and/or active feedback on edge microstability, large edge electric fields, and two-fluid modelling of non-ambipolar scrape-off layers. Section (3) contained (i) a proposal to construct a spherical tokamak ''Proto-Eta'', (ii) an analysis of ultra-low-q and runaway

  12. 21 CFR 172.876 - Castor oil.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Castor oil. 172.876 Section 172.876 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Multipurpose Additives § 172.876 Castor oil. The food additive castor oil may be safely used in accordance with...

  13. Tokamak formation and sustainment by tokamak injection

    International Nuclear Information System (INIS)

    Farengo, R.; Jarboe, T.R.

    1991-01-01

    The authors propose here a new helicity injection method for tokamak formation and sustainment that has high efficiency, conserves toroidal symmetry and is inductively driven. The basic idea is to inject a small tokamak (source tokamak) into a larger tokamak (steady tokamak). This current drive scheme eliminates the need for the ohmic heating transformer in the steady tokamak allowing the formation of very small aspect ratio tokamaks (Spherical Tori). Thus, steady state operation and high beta can be realized simultaneously. The method can also be applied to a larger aspect ratio tokamak and used in conjunction with the standard inductive formation technique. In order to allow for translation the ohmic heating coil used to produce the source tokamaks must be fed from one end (as in the CSS device) and the toroidal field coil must link both tokamaks. After formation the source tokamaks are accelerated towards the steady tokamak by a mirror field and the tension of the field lines that wrap around both tokamaks (producing a doublet type configuration). In a tokamak the helicity is proportional to the current. This indicates that (assuming helicity is conserved during the merging process) a steady state situation will result if the helicity supplied by the source tokamaks is equal to the helicity dissipated by the steady tokamak. Assuming that source tokamaks of helicity K s are injected with frequency f, the steady state condition can be written as: fK s = 2V t Ψ t = K t /τ K where V t , Ψ t , K t and τ K are the ohmic loop voltage, toroidal flux, helicity and helicity decay time of the steady tokamak. A simple calculation shows that the DIII-D tokamak could be sustained by injecting source tokamaks with R = 1.20 m, a = 0.23 m and I = 151 kA at a frequency of 120 Hz. 1 ref

  14. Tokamak COMPASS

    Czech Academy of Sciences Publication Activity Database

    Řípa, Milan; Křenek, Petr

    2011-01-01

    Roč. 17, č. 1 (2011), s. 32-34 ISSN 1210-4612 Institutional research plan: CEZ:AV0Z20430508 Keywords : fusion * tokamak * Compass * Golem * Institute of Plasma Physics AVCR v.v * NBI * diagnostics Subject RIV: BL - Plasma and Gas Discharge Physics

  15. Microwave experiments on the tokamak CASTOR: fundamental ECE radiometry

    Czech Academy of Sciences Publication Activity Database

    Zajac, Jaromír; Preinhaelter, Josef; Žáček, František; Nanobashvili, S.

    2004-01-01

    Roč. 54, suppl. C (2004), C68-C73 ISSN 0011-4626. [Symposium on Plasma Physics and Technology /21st/. Praha, 14.06.2004-17.06.2004] R&D Projects: GA ČR GA202/00/1215 Grant - others:INTAS(XE) 2001 1B-2056 Institutional research plan: CEZ:AV0Z2043910 Keywords : electron cyclotron, emission, electron Bernstein waves, plasma radiometry Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.292, year: 2004

  16. Labelling of castor oil for myocardial study

    International Nuclear Information System (INIS)

    Hallaba, E.; Al-Suhybani, A.; Zaki, F.S.; Abdullah, M.E.

    1985-01-01

    The labelling of castor oil, hydrolyzed castor oil and oleic acid by iodine monochloride and chloramine-T was investigated. The effect of iodinating agent and concentration of castor oil on labelling yield was studied. A comparative pharmacological study with analog aliphatic acids was carried out. Castor oil labelled with iodine monochloride concentrates in heart and liver in good proportion, better than other natural fatty acids and nearly equal to analog fatty acids. Infrared study revealed that the OH group in ricinoleic acid may protect the sup(125)I added across the double bond with minor changes in biochemical properties causing better extraction by muscle of the heart. (author)

  17. Castor Oil-Based Biodegradable Polyesters.

    Science.gov (United States)

    Kunduru, Konda Reddy; Basu, Arijit; Haim Zada, Moran; Domb, Abraham J

    2015-09-14

    This Review compiles the synthesis, physical properties, and biomedical applications for the polyesters based on castor oil and ricinoleic acid. Castor oil has been known for its medicinal value since ancient times. It contains ∼90% ricinoleic acid, which enables direct chemical transformation into polyesters without interference of other fatty acids. The presence of ricinoleic acid (hydroxyl containing fatty acid) enables synthesis of various polyester/anhydrides. In addition, castor oil contains a cis-double bond that can be hydrogenated, oxidized, halogenated, and polymerized. Castor oil is obtained pure in large quantities from natural sources; it is safe and biocompatible.

  18. Synthesis of novel castor oil phosphonates

    Science.gov (United States)

    Castor oil has served as a versatile hydroxy fatty acid (HFA); its principle component, ricinoleic acid, can be isolated from castor oil and has been modified extensively for a number of applications. Additionally, phosphonates and their corresponding phosphonic acids are a functional moiety that ha...

  19. Weed management strategies for castor bean crops

    Directory of Open Access Journals (Sweden)

    Augusto Guerreiro Fontoura Costa

    2014-04-01

    Full Text Available Castor bean crops are agriculturally relevant due to the quality and versatility of their oil, both for the chemical industry and for biodiesel production. Proper weed management is important for both the cultivation and the yield of castor bean crops; therefore, the intention of the present work is to review pertinent information regarding weed management, including the studies regarding weed interference periods, chemical controls for use in different crop production systems and herbicide selectivity, for castor bean crops. Weed science research for castor bean crops is scarce. One of the main weed management challenges for castor bean crops is the absence of herbicides registered with the Ministry of Agriculture, Livestock and Food Supply (MALFS. Research for viable herbicides for weed control in castor bean crops should be directed by research and/or rural extension institutions, associations and farmers cooperatives, as well as by manufactures, for the registration of these selective herbicides, which would be primarily used to control eudicotyledons in castor bean crops. New studies involving the integration of weed control methods in castor bean also may increase the efficiency of weed management, for both small farmers using traditional crop methods in the Brazilian Northeast region, as well as for areas with the potential for large scale production, using conservation tillage systems, such as the no-tillage crop production system.

  20. Tokamak physics

    International Nuclear Information System (INIS)

    Haines, M.G.

    1984-01-01

    The physical conditions required for breakeven in thermonuclear fusion are derived, and the early conceptual ideas of magnetic confinement and subsequent development are followed, leading to present-day large scale tokamak experiments. Confinement and diffusion are developed in terms of particle orbits, whilst magnetohydrodynamic stability is discussed from energy considerations. From these ideas are derived the scaling laws that determine the physical size and parameters of this fusion configuration. It becomes clear that additional heating is required. However there are currently several major gaps in our understanding of experiments; the causes of anomalous electron energy loss and the major current disruption, the absence of the 'bootstrap' current and what physics determines the maximum plasma pressure consistent with stability. The understanding of these phenomena is a major challenge to plasma physicists. (author)

  1. PPPL tokamak program

    International Nuclear Information System (INIS)

    Furth, H.P.

    1984-10-01

    The economic prospects of the tokamak are reviewed briefly and found to be favorable - if the size of ignited tokamak plasmas can be kept small and appropriate auxiliary systems can be developed. The main objectives of the Princeton Plasma Physics Laboratory tokamak program are: (1) exploration of the physics of high-temperature toroidal confinement, in TFTR; (2) maximization of the tokamak beta value, in PBX; (3) development of reactor-relevant rf techniques, in PLT

  2. Status of tokamak research

    International Nuclear Information System (INIS)

    Rawls, J.M.

    1979-10-01

    An overall review of the tokamak program is given with particular emphasis upon developments over the past five years in the theoretical and experimental elements of the program. A summary of the key operating parameters for the principal tokamaks throughout the world is given. Also discussed are key issues in plasma confinement, plasma heating, and tokamak design

  3. Status of tokamak research

    Energy Technology Data Exchange (ETDEWEB)

    Rawls, J.M. (ed.)

    1979-10-01

    An overall review of the tokamak program is given with particular emphasis upon developments over the past five years in the theoretical and experimental elements of the program. A summary of the key operating parameters for the principal tokamaks throughout the world is given. Also discussed are key issues in plasma confinement, plasma heating, and tokamak design. (MOW)

  4. Tokamak Systems Code

    International Nuclear Information System (INIS)

    Reid, R.L.; Barrett, R.J.; Brown, T.G.

    1985-03-01

    The FEDC Tokamak Systems Code calculates tokamak performance, cost, and configuration as a function of plasma engineering parameters. This version of the code models experimental tokamaks. It does not currently consider tokamak configurations that generate electrical power or incorporate breeding blankets. The code has a modular (or subroutine) structure to allow independent modeling for each major tokamak component or system. A primary benefit of modularization is that a component module may be updated without disturbing the remainder of the systems code as long as the imput to or output from the module remains unchanged

  5. Labelling of castor oil for myocardial studies

    International Nuclear Information System (INIS)

    Hallaba, E.; Al-Suhybani, A.; Zaki, F.S.; Abdullah, M.E.

    1985-01-01

    The labelling of castor oil, hydrolysed castor oil and oleic acid was investigated by the iodine monochloride and chloramine-T methods. The effect of the iodinating agent and the concentration of castor oil on the labelling yield was studied. A comparative pharmacological study with analog aliphatic fatty acids was carried out. Castor oil labelled with iodine monochloride concentrated in the heart and liver in good proportion, better than other natural fatty acids and nearly equal to analog aliphatic fatty acids. An infra-red study showed that the OH group of the ricinoleic acid apparently protects the 125 I added on the double bond, with minor changes in biochemical properties and better uptake by the heart muscle. (author)

  6. Carboxypeptidase of Castor Bean Endosperm during Germination

    OpenAIRE

    山本, 知子; 下田, 忠久; 船津, 軍喜; Yamamoto, Tomoko; Shimoda, Tadahisa; Funatsu, Gunki

    1982-01-01

    Carboxypeptidase (CPase) in the endosperm of castor bean (Ricinus communis L.) showed high activity at day 4 and 7 on germination. From the behavior of CPases on CM-cellulose column chromatography, the early stage CPases, which appeared before 4 day germination, were different from the later stage CPases which appeared after 6 day. Probably the former arised from ungerminated seeds and the latter was synthesized during the germination. The early stage endosperm of small grain castor bean cont...

  7. Tokamak engineering mechanics

    International Nuclear Information System (INIS)

    Song, Yuntao; Wu, Weiyue; Du, Shijun

    2014-01-01

    Provides a systematic introduction to tokamaks in engineering mechanics. Includes design guides based on full mechanical analysis, which makes it possible to accurately predict load capacity and temperature increases. Presents comprehensive information on important design factors involving materials. Covers the latest advances in and up-to-date references on tokamak devices. Numerous examples reinforce the understanding of concepts and provide procedures for design. Tokamak Engineering Mechanics offers concise and thorough coverage of engineering mechanics theory and application for tokamaks, and the material is reinforced by numerous examples. Chapter topics include general principles, static mechanics, dynamic mechanics, thermal fluid mechanics and multiphysics structural mechanics of tokamak structure analysis. The theoretical principle of the design and the methods of the analysis for various components and load conditions are presented, while the latest engineering technologies are also introduced. The book will provide readers involved in the study of mechanical/fusion engineering with a general understanding of tokamak engineering mechanics.

  8. Tokamak engineering mechanics

    CERN Document Server

    Song, Yuntao; Du, Shijun

    2013-01-01

    Tokamak Engineering Mechanics offers concise and thorough coverage of engineering mechanics theory and application for tokamaks, and the material is reinforced by numerous examples. Chapter topics include general principles, static mechanics, dynamic mechanics, thermal fluid mechanics and multiphysics structural mechanics of tokamak structure analysis. The theoretical principle of the design and the methods of the analysis for various components and load conditions are presented, while the latest engineering technologies are also introduced. The book will provide readers involved in the study

  9. Tokamak confinement scaling laws

    International Nuclear Information System (INIS)

    Connor, J.

    1998-01-01

    The scaling of energy confinement with engineering parameters, such as plasma current and major radius, is important for establishing the size of an ignited fusion device. Tokamaks exhibit a variety of modes of operation with different confinement properties. At present there is no adequate first principles theory to predict tokamak energy confinement and the empirical scaling method is the preferred approach to designing next step tokamaks. This paper reviews a number of robust theoretical concepts, such as dimensional analysis and stability boundaries, which provide a framework for characterising and understanding tokamak confinement and, therefore, generate more confidence in using empirical laws for extrapolation to future devices. (author)

  10. Response of clarias gariepinus to dietary castor seeds processed by ...

    African Journals Online (AJOL)

    Castor seed variously treated by boiling, roasting, boiling and roasting, decorticated lyle treated, boiling and fermenting was tested for improved nutrient content and elimination of toxins. 10% processed castor seed cake (CSC) was included in diets and fed to 180 catfishes for 4-weeks to assay the dietary castor seed based ...

  11. 21 CFR 178.3280 - Castor oil, hydrogenated.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Castor oil, hydrogenated. 178.3280 Section 178.3280 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Certain Adjuvants and Production Aids § 178.3280 Castor oil, hydrogenated. Hydrogenated castor oil may be...

  12. 75 FR 44917 - Castor Oil, Ethoxylated, Dioleate; Tolerance Exemption

    Science.gov (United States)

    2010-07-30

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA-HQ-OPP-2010-0232; FRL-8835-3] Castor Oil... castor oil, ethoxylated, dioleate; when used as an inert ingredient in a pesticide chemical formulation.... This regulation eliminates the need to establish a maximum permissible level for residues of castor oil...

  13. 75 FR 40751 - Castor Oil, Ethoxylated, Oleate; Tolerance Exemption

    Science.gov (United States)

    2010-07-14

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA-HQ-OPP-2010-0231; FRL-8834-4] Castor Oil... castor oil, ethoxylated, oleate (CAS Reg. No. 220037-02-5) with a minimum number average molecular weight... regulation eliminates the need to establish a maximum permissible level for residues of castor oil...

  14. Castor bean response to zinc fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Lucia Helena Garofalo; Cunha, Tassio Henrique Cavalcanti da Silva; Lima, Vinicius Mota; Cabral, Paulo Cesar Pinto; Barros Junior, Genival; Lacerda, Rogerio Dantas de [Universidade Federal de Campina Grande (UAEAg/UFCG), PB (Brazil). Unidade Academica de Engenharia Agricola

    2008-07-01

    Zinc is a trace element and it is absolutely essential for the normal healthy growth of plants. This element plays a part of several enzyme systems and other metabolic functions in the plants. Castor beans (Ricinus communis L.) crop is raising attention as an alternative crop for oil and biodiesel production. Despite the mineral fertilization is an important factor for increasing castor beans yield, few researches has been made on this issue, mainly on the use of zinc. In order to evaluate the effects of zinc on growth of this plant an experiment was carried out in a greenhouse, in Campina Grande, Paraiba State, Brazil, from July to December 2007. The substrate for the pot plants was a 6 mm-sieved surface soil (Neossolo Quartzarenico). The experimental design was a completely randomized with three replications. The treatments were composed of five levels of Zn (0; 2; 4; 6 and 8 mg dm{sup -3}), which were applied at the time of planting. One plant of castor bean, cultivar BRS 188 - Paraguacu, was grown per pot after thinning and was irrigated whenever necessary. Data on plant height, number and length of leaves and stem diameter were measured at 21, 34, 77 and 103 days after planting. Under conditions that the experiment was carried out the results showed that the Zn levels used, did not affect the castor bean plants growth. (author)

  15. (11) EFFECT OF POWDERED CASTOR BEAN

    African Journals Online (AJOL)

    Adeyinka Odunsi

    A study was carried out at the Toxicology laboratory of the Department of Crop and Environmental protection,. Ladoke Akintola University of Technology Ogbomoso, to determine the effects of powdered castor oil seed. (Ricinus communis L.Euphorbiaceae) on kidney, liver, spleen of albino rats. The rats were in five groups, ...

  16. Tough Blends of Polylactide and Castor Oil

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Megan L.; Paxton, Jessica M.; Hillmyer, Marc A. (UMM)

    2012-10-10

    Poly(l-lactide) (PLLA) is a renewable resource polymer derived from plant sugars with several commercial applications. Broader implementation of the material is limited due to its inherent brittleness. We show that the addition of 5 wt % castor oil to PLLA significantly enhances the overall tensile toughness with minimal reductions in the modulus and no plasticization of the PLLA matrix. In addition, we used poly(ricinoleic acid)-PLLA diblock copolymers, synthesized entirely from renewable resources, as compatibilizers for the PLLA/castor oil blends. Ricinoleic acid, the majority fatty acid comprising castor oil, was polymerized through a lipase-catalyzed condensation reaction. The resulting polymers contained a hydroxyl end-group that was subsequently used to initiate the ring-opening polymerization of L-lactide. The binary PLLA/castor oil blend exhibited a tensile toughness seven times greater than neat PLLA. The addition of block copolymer allowed for control over the morphology of the blends, and even further improvement in the tensile toughness was realized - an order of magnitude larger than that of neat PLLA.

  17. Phenylpropanoid esters of lesquerella and castor oil

    Science.gov (United States)

    Lesquerella (LO) and castor oil (CO) were esterified at the secondary hydroxyl groups of their 14-hydroxyeicos-cis-11-enoic fatty acids and 12-hydroxyoctadec-cis-9-enoic fatty acids, respectively, with 4-acetoxy-3-methoxycinnamic acid (acetoxyferulic acid). The unconventional esterifications were co...

  18. Tough blends of polylactide and castor oil.

    Science.gov (United States)

    Robertson, Megan L; Paxton, Jessica M; Hillmyer, Marc A

    2011-09-01

    Poly(l-lactide) (PLLA) is a renewable resource polymer derived from plant sugars with several commercial applications. Broader implementation of the material is limited due to its inherent brittleness. We show that the addition of 5 wt % castor oil to PLLA significantly enhances the overall tensile toughness with minimal reductions in the modulus and no plasticization of the PLLA matrix. In addition, we used poly(ricinoleic acid)-PLLA diblock copolymers, synthesized entirely from renewable resources, as compatibilizers for the PLLA/castor oil blends. Ricinoleic acid, the majority fatty acid comprising castor oil, was polymerized through a lipase-catalyzed condensation reaction. The resulting polymers contained a hydroxyl end-group that was subsequently used to initiate the ring-opening polymerization of l-lactide. The binary PLLA/castor oil blend exhibited a tensile toughness seven times greater than neat PLLA. The addition of block copolymer allowed for control over the morphology of the blends, and even further improvement in the tensile toughness was realized-an order of magnitude larger than that of neat PLLA.

  19. (11) EFFECT OF POWDERED CASTOR BEAN

    African Journals Online (AJOL)

    Adeyinka Odunsi

    Ricinus communis, are poisonous to people, animals and insects. One of the main toxic proteins is "ricin", named by ... whereas RCA is a weak cytotoxin and a powerful hemagglutinin. Poisoning by exposure to castor oil seed .... Both red and the white pulps are distinguishable and numerous small vascular channels are ...

  20. Survey of Tokamak experiments

    International Nuclear Information System (INIS)

    Bickerton, R.J.

    1977-01-01

    The survey covers the following topics:- Introduction and history of tokamak research; review of tokamak apparatus, existing and planned; remarks on measurement techniques and their limitations; main results in terms of electron and ion temperatures, plasma density, containment times, etc. Empirical scaling; range of operating densities; impurities, origin, behaviour and control (including divertors); data on fluctuations and instabilities in tokamak plasmas; data on disruptive instabilities; experiments on shaped cross-sections; present experimental evidence on β limits; auxiliary heating; experimental and theoretical problems for the future. (author)

  1. Tokamak ARC damage

    Energy Technology Data Exchange (ETDEWEB)

    Murray, J.G.; Gorker, G.E.

    1985-01-01

    Tokamak fusion reactors will have large plasma currents of approximately 10 MA with hundreds of megajoules stored in the magnetic fields. When a major plasma instability occurs, the disruption of the plasma current induces voltage in the adjacent conducting structures, giving rise to large transient currents. The induced voltages may be sufficiently high to cause arcing across sector gaps or from one protruding component to another. This report reviews a tokamak arcing scenario and provides guidelines for designing tokamaks to minimize the possibility of arc damage.

  2. Tokamak ARC damage

    International Nuclear Information System (INIS)

    Murray, J.G.; Gorker, G.E.

    1985-01-01

    Tokamak fusion reactors will have large plasma currents of approximately 10 MA with hundreds of megajoules stored in the magnetic fields. When a major plasma instability occurs, the disruption of the plasma current induces voltage in the adjacent conducting structures, giving rise to large transient currents. The induced voltages may be sufficiently high to cause arcing across sector gaps or from one protruding component to another. This report reviews a tokamak arcing scenario and provides guidelines for designing tokamaks to minimize the possibility of arc damage

  3. Research using small tokamaks

    International Nuclear Information System (INIS)

    1989-07-01

    These proceedings of the IAEA-sponsored meeting held in Nice, France 10-11 October, 1988, contain the manuscripts of the 21 reports dealing with research using small tokamaks. The purpose of this meeting was to highlight some of the achievements of small tokamaks and alternative magnetic confinement concepts and assess the suitability of starting new programs, particularly in developing countries. Papers presented were either review papers, or were detailed descriptions of particular experiments or concepts. Refs, figs and tabs

  4. Tokamak simulation code manual

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Moon Kyoo; Oh, Byung Hoon; Hong, Bong Keun; Lee, Kwang Won [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-01-01

    The method to use TSC (Tokamak Simulation Code) developed by Princeton plasma physics laboratory is illustrated. In KT-2 tokamak, time dependent simulation of axisymmetric toroidal plasma and vertical stability have to be taken into account in design phase using TSC. In this report physical modelling of TSC are described and examples of application in JAERI and SERI are illustrated, which will be useful when TSC is installed KAERI computer system. (Author) 15 refs., 6 figs., 3 tabs.

  5. Tokamak simulation code manual

    International Nuclear Information System (INIS)

    Chung, Moon Kyoo; Oh, Byung Hoon; Hong, Bong Keun; Lee, Kwang Won

    1995-01-01

    The method to use TSC (Tokamak Simulation Code) developed by Princeton plasma physics laboratory is illustrated. In KT-2 tokamak, time dependent simulation of axisymmetric toroidal plasma and vertical stability have to be taken into account in design phase using TSC. In this report physical modelling of TSC are described and examples of application in JAERI and SERI are illustrated, which will be useful when TSC is installed KAERI computer system. (Author) 15 refs., 6 figs., 3 tabs

  6. Joint research using small tokamaks

    International Nuclear Information System (INIS)

    Gryaznevich, M.P.; Del Bosco, E.; Malaquias, A.; Mank, G.; Oost, G. van

    2005-01-01

    Small tokamaks have an important role in fusion research. More than 40 small tokamaks are operational. Research on small tokamaks has created a scientific basis for the scaling-up to larger tokamaks. Well-known scientific and engineering schools, which are now determining the main directions of fusion science and technology, have been established through research on small tokamaks. Combined efforts within a network of small and medium size tokamaks will further enhance the contribution of small tokamaks. A new concept of interactive co-ordinated research using small tokamaks in the mainstream fusion science areas, in testing of new diagnostics, materials and technologies as well as in education, training and broadening of the geography of fusion research in the scope of the IAEA Co-ordinated Research Project is presented. (author)

  7. Cyclotron radiation as Tokamak diagnostics

    International Nuclear Information System (INIS)

    Fiedler-Ferrari, N.

    1985-01-01

    A brief introduction to the use of Electron Cyclotron Emission as diagnostics in tokamaks is made. The utilization feasibility of this dignostics in the TBR-1 and TTF2A tokamaks is discussed. (L.C.) [pt

  8. Optimization of biodiesel production from castor oil.

    Science.gov (United States)

    da Silva, Nivea de Lima; Maciel, Maria Regina Wolf; Batistella, César Benedito; Maciel Filho, Rubens

    2006-01-01

    The transesterification of castor oil with ethanol in the presence of sodium ethoxide as catalyst is an exceptional option for the Brazilian biodiesel production, because the castor nut is quite available in the country. Chemically, its oil contains about 90% of ricinoleic acid that gives to the oil some beneficial characteristics such as its alcohol solubility at 30 degrees C. The transesterification variables studied in this work were reaction temperature, catalyst concentration and alcohol oil molar ratio. Through a star configuration experimental design with central points, this study shows that it is possible to achieve the same conversion of esters carrying out the transesterification reaction with a smaller alcohol quantity, and a new methodology was developed to obtain high purity biodiesel.

  9. Agronomically valuable mutant lines of castor

    International Nuclear Information System (INIS)

    Bokhan, I.K.

    1990-01-01

    Dry seeds of four castor varieties (VNIIMK 165-improved, VNIIMK 18, Chervonnaya and Antika) were treated with six chemical mutagens, N-nitroso-N-methyl urea (NMU), N-nitroso-N-ethyl urea (NEU), dimethyl sulphate (DMS), diethyl sulphate (DES), ethylenimine (EI) and 1,4-bis-diazoacetyl-butane (DAB) in various doses during 18 hours. About 40,000 plants were studied in M 2 and 80 types of mutations were found, including a number of valuable mutants: short-stemmed, semi-dwarf, dwarf, early maturing, with female and interspersed types of racemes, highly productive etc. Based on trials in M 3 -M 4 , on small plots with two or three replications, the superior mutant lines were identified. The best mutants are presented in the table. Early maturation is very important for growing castor in the USSR, as it is the predecessor of winter wheat in crop rotation. The mutants M2-323 and Ml-83 are of great value as they show early maturation and high yield. Their productivity is mainly conditioned by a high percentage of interspersed plants. The reduction of plant height is of great importance for the successful combine harvesting of castor. Mutant lines M2-119 and Ml-284 characterised by low plant height and high yield are very interesting in this respect. The obtained initial material will be used in further breeding work

  10. Synthesis of branched naphthoquinones from castor oil

    Directory of Open Access Journals (Sweden)

    Adriano Olímpio da Silva

    2012-06-01

    Full Text Available The naphthoquinones are cyclic aromatic α,β-dienonas with a basic framework derived from naphthalene. They are also found in many higher plants, algae, fungi and as the product of the  metabolism  of some  bacteria  having large biologica activity described in the literature such as antibacterial, anti-inflammatory, antitumor, anticancer and trypanocidal [1-3]. Castor oil is an abundant raw material in Brazil of great versatility and, it is present in biodiesel production, surfactants, cosmetics and others. Considering the importance of naphthoquinones and, the availability of the ricinoleic acid from castor oil, the aim of this study was the preparation of new branched naphthoquinones in order to test their trypanocidal activity. Castor oil was submitted to saponification with sodium hydroxide, ethanol and water under reflux for 6 h. We then carried out an acid hydrolysis with hydrochloric acid and the formed ricinoleic acid was extracted with ethyl acetate. Following, through Kochi-Anderson addition reaction it was performed the alkylation of a naphthoquinone 1 and 2, using ammonium persulfate, silver nitrate, acetonitrile and water, under heating at 70-80 ° C during 3 h, to give the branched naphthoquinones 4 and 5 (scheme 1. The naphthoquinone 3 will be similarly submitted to this procedure. The naphthoquinones 4 and 5 were purified by column chromatography on sílica gel using hexane as the eluent. The compounds were characterized by mass spectrometry and 1H and 13CNMR spectroscopy.

  11. LHCb: CASTORFS - A Filesystem to Access CASTOR

    CERN Multimedia

    Mazurov, A

    2009-01-01

    CASTOR provides a powerful and rich interface for managing files and pools of files backed by tape-storage. The API is modelled very closely on that of a POSIX filesystem, where part of the actual I/O part is handled by the rfio library. While the API is very close to POSIX it is still separated, which unfortunately makes it impossible to use standard tools and scripts straight away. This is particularly inconvenient when applications are written in languages other than C/C++ such as is frequently the case in web-apps. Here up to now the only the recourse was to use command-line utilities and parse their output, which is clearly a kludge. We have implemented a complete POSIX filesystem to access CASTOR using FUSE (Filesystem in Userspace) and have successfully tested and used this on SLC4 and SLC5 (both in 32 and 64 bit). We call it CastorFS. In this paper we will present its architecture and implementation, with emphasis on performance and caching aspects.

  12. Use of castor oil in pregnancies at term.

    Science.gov (United States)

    Garry, D; Figueroa, R; Guillaume, J; Cucco, V

    2000-01-01

    Despite wide use of castor oil to initiate labor, the obstetric literature contains few references to this botanical laxative. Derived from the castor plant Ricinus communis, castor oil may possess properties that are useful in post-term pregnancies. To evaluate the relationship between the use of castor oil and the onset of labor. Prospective evaluation. A community hospital in Brooklyn, NY. A total of 103 singleton pregnancies with intact membranes at 40 to 42 weeks referred for antepartum testing. Inclusion criteria included cervical examination, Bishop score of 4 or less, and no evidence of regular uterine contractions. Patients were alternately assigned to 1 of 2 study groups: a single oral dose of castor oil (60 mL) or no treatment. Castor oil was considered successful if labor began within 24 hours after dosing. Groups were compared for onset of labor in 24 hours, method of delivery, presence of meconium-stained amniotic fluid, Apgar score, and birth weight. Fifty-two women received castor oil and 48 were assigned no treatment. Following administration of castor oil, 30 of 52 women (57.7%) began active labor compared to 2 of 48 (4.2%) receiving no treatment. When castor oil was successful, 83.3% (25/30) of the women delivered vaginally. Women who receive castor oil have an increased likelihood of initiation of labor within 24 hours compared to women who receive no treatment. Castor oil use in pregnancy is underreported worldwide. This small series represents the first attempt to evaluate the medication.

  13. Advanced statistics for tokamak transport colinearity and tokamak to tokamak variation

    International Nuclear Information System (INIS)

    Riedel, K.S.

    1989-03-01

    This is a compendium of three separate articles on the statistical analysis of tokamak transport. The first article is an expository introduction to advanced statistics and scaling laws. The second analyzes two important problems of tokamak data---colinearity and tokamak to tokamak variation in detail. The third article generalizes the Swamy random coefficient model to the case of degenerate matrices. Three papers have been processed separately

  14. Texas Experimental Tokamak

    International Nuclear Information System (INIS)

    Wootton, A.J.

    1993-04-01

    This progress report covers the period from November 1, 1990 to April 30, 1993. During that period, TEXT was operated as a circular tokamak with a material limiter. It was devoted to the study of basic plasma physics, in particular to study of fluctuations, turbulence, and transport. The purpose is to operate and maintain TEXT Upgrade as a complete facility for applied tokamak physics, specifically to conduct a research program under the following main headings: (1) to elucidate the mechanisms of working gas, impurity, and thermal transport in tokamaks, in particular to understand the role of turbulence; (2) to study physics of the edge plasma, in particular the turbulence; (3) to study the physics or resonant magnetic fields (ergodic magnetic divertors, intra island pumping); and (4) to study the physics of electron cyclotron heating (ECRH). Results of studies in each of these areas are reported

  15. Microwave Tokamak Experiment

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The Microwave Tokamak Experiment, now under construction at the Laboratory, will use microwave heating from a free-electron laser. The intense microwave pulses will be injected into the tokamak to realize several goals, including a demonstration of the effects of localized heat deposition within magnetically confined plasma, a better understanding of energy confinement in tokamaks, and use of the new free-electron laser technology for plasma heating. The experiment, soon to be operational, provides an opportunity to study dense plasmas heated by powers unprecedented in the electron-cyclotron frequency range required by the especially high magnetic fields used with the MTX and needed for reactors. 1 references, 5 figures, 3 tables

  16. Accelerator technology in tokamaks

    International Nuclear Information System (INIS)

    Kustom, R.L.

    1977-01-01

    This article presents the similarities in the technology required for high energy accelerators and tokamak fusion devices. The tokamak devices and R and D programs described in the text represent only a fraction of the total fusion program. The technological barriers to producing successful, economical tokamak fusion power plants are as many as the plasma physics problems to be overcome. With the present emphasis on energy problems in this country and elsewhere, it is very likely that fusion technology related R and D programs will vigorously continue; and since high energy accelerator technology has so much in common with fusion technology, more scientists from the accelerator community are likely to be attracted to fusion problems

  17. Synthesis and characterization of castor oil-based polyurethane for ...

    Indian Academy of Sciences (India)

    Polyurethane (PU) based on polyol, derived from castor oil has been synthesized and characterized for potential use as a base material for electrolytes. Transesterification process of castor oil formed a polyol with hydroxyl value of 190 mg KOH g–1 and molecular weight of 2786 g mol–1. The polyols together with 4 ...

  18. Synthesis and characterization of castor oil-based polyurethane for ...

    Indian Academy of Sciences (India)

    Administrator

    adhesives and thermal insulation.14–16 However, modifica- tion of PU for use as host in polymer electrolytes has not ... is no report related to the potential of castor oil-polyol- based PU as host in polymer electrolytes. ... The reactor was filled with castor oil and 15 wt% of gly- cerol was added to it. The percentage of the ...

  19. Allelopathic effect of aqueous extract of fresh leaf castor beans ...

    African Journals Online (AJOL)

    Allelopathy defines the production of specific biomolecules (allelochemical) by a plant that can induce positive or negative impacts on another culture. The crop of castor beans (Ricinus communis L.) is being economically valued and receiving attention, mainly by the biodiesel production, castor oil and animal feeding.

  20. Novel alpha-hydroxy phosphonic acids via castor oil

    Science.gov (United States)

    Hydroxy fatty acids (HFAs) have found a number of uses in today’s market, with uses ranging from materials to pharmaceuticals. Castor oil has served as a versatile HFA; its principle component, ricinoleic acid, can be isolated from castor oil and has been modified extensively for a number of applica...

  1. VARIATIONS IN SEED TRAITS OF CASTOR (Ricinus communis ...

    African Journals Online (AJOL)

    The sizes of castor seed have been reported to vary from a few millimeters long to about 20 mm in the giant species (Weiss, 2000). The seed weight varies. For instance, seeds found in Nigeria and Kenya has been reported to weigh. 69.3 and 59.2 g, respectively (Li et al., 2008). The typical fatty acid composition of castor oil.

  2. Synthesis and characterization of castor oil-based polyurethane

    Indian Academy of Sciences (India)

    Polyurethane (PU) based on polyol, derived from castor oil has been synthesized and characterized for potential use as a base material for electrolytes. Transesterification process of castor oil formed a polyol with hydroxyl value of 190 mg KOH g–1 and molecular weight of 2786 g mol–1. The polyols together with 4 ...

  3. Allelopathic effect of aqueous extract of fresh leaf castor beans ...

    African Journals Online (AJOL)

    Rukevwe S. Abraka

    2016-12-07

    Dec 7, 2016 ... Allelopathy defines the production of specific biomolecules (allelochemical) by a plant that can induce positive or negative impacts on another culture. The crop of castor beans (Ricinus communis L.) is being economically valued and receiving attention, mainly by the biodiesel production, castor oil and.

  4. Synthesis and characterization of castor oil based polyurethane ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. A series of interpenetrating polymer networks (IPNs) of castor oil based polyurethane/polyacrylo- nitrile (PU/PAN: 80/20, 60/40, 50/50, 40/60 and 20/80) were synthesized by condensation reaction of castor oil with methylene diisocyanate and acrylonitrile, employing benzoyl peroxide (BPO) and ethylene glycol ...

  5. Screening of spontaneous castor bean accesses for genetic ...

    African Journals Online (AJOL)

    ... discriminant power between the castor bean accesses, being the multivariate analysis efficient in this process. The castor bean accesses ACS-001 CRSP and ACS-001-MASP are promising for introduction in genetic improvement programs of this culture. Keywords: Ricinus communis L., genotype, multivariate statistics, ...

  6. Screening of spontaneous castor bean accesses for genetic ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    2016-10-05

    Oct 5, 2016 ... castor bean accesses, being the multivariate analysis efficient in this process. The castor bean accesses ACS-001-CRSP and ACS-001-MASP are promising for introduction in genetic improvement programs of this culture. Key words: Ricinus communis L., genotype, multivariate statistics, bioenergy.

  7. Registration of Crop Varieties A Unique Purple Castor (Racinnus ...

    African Journals Online (AJOL)

    Most of the castor produced in Russia,. USA, Israel, Brazil, China and India comes from hybrid varieties. In 1999 a unique purple castor population was noticed during a field trip at. Adullala near Melkassa. One killo gram of seed was abstained from the farmer, and mass selection for uniformity, top branching and short plant.

  8. Synthesis and characterization of castor oil-based polyurethane for ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Polyurethane (PU) based on polyol, derived from castor oil has been synthesized and characterized for potential use as a base material for electrolytes. Transesterification process of castor oil formed a polyol with hydroxyl value of 190 mg KOH g–1 and molecular weight of 2786 g mol–1. The polyols together with.

  9. Interpenetrating polymer networks based on polyol modified castor ...

    Indian Academy of Sciences (India)

    Unknown

    glycerol modification of castor oil results in more crosslinked and stiffer IPNs possessing better mechanical properties over that of unmodified castor oil polyurethane/. PHEMA IPNs. 3.5 Chemical resistance. The percentage weight loss of IPNs were determined in. H2SO4, CH3COOH, HCl, HNO3, NaCl and NaOH etc and.

  10. ARIES tokamak reactor study

    International Nuclear Information System (INIS)

    Steiner, D.; Embrechts, M.

    1990-07-01

    This is a status report on technical progress relative to the tasks identified for the fifth year of Grant No. FG02-85-ER52118. The ARIES tokamak reactor study is a multi-institutional effort to develop several visions of the tokamak as an attractive fusion reactor with enhanced economic, safety, and environmental features. The ARIES study is being coordinated by UCLA and involves a number of institutions, including RPI. The RPI group has been pursuing the following areas of research in the context of the ARIES-I design effort: MHD equilibrium and stability analyses; plasma-edge modeling and blanket materials issues. Progress in these areas is summarized herein

  11. High beta tokamak instabilities

    International Nuclear Information System (INIS)

    Bateman, G.

    1977-01-01

    Theoretical predictions using the ideal MHD model indicable that large-scale ballooning modes should appear when the average beta is raised about 1 to 2% in present-day tokamak geometries or 5 to 10% in more optimized geometries. The onset of instability is predicted to be sudden and the behavior of ballooning modes to be strikingly different from the saw-tooth and Mirnov oscillations experimentally observed at low beta. Conditions close to the predicted onset were achieved in ORMAK with no noticeable change in plasma behavior. Experiments are planned for the ISX tokamak to test the beta limit. 15 references, 3 figures

  12. Long Pulse Technology Tokamak

    International Nuclear Information System (INIS)

    Jernigan, T.C.

    1978-01-01

    The LPTT tokamak is a non-circular tokamak (R = 1.5 m, a = .45 m) proposed by ORNL for extended pulse operation at high β (5%) and reactor level wall power loading (40 w/cm 2 ). The toroidal field coils are superconducting and a super-conducting bundle divertor is proposed for active impurity control. All systems are designed for continuous operation which will provide pulse lengths > 20 seconds with a 6 to 10 weber flux swing. Experimental access and flexibility in operation are primary design goals

  13. Diversity of Castor (Ricinus communis L.) in Ethiopia አህፅርኦት ...

    African Journals Online (AJOL)

    In Ethiopia, Castor grows as annual in the low lands to small tree perennial in the high lands. India, china, Brazil and USA are the major castor producers globally. Castor bears seeds that containing highly valuable industrial oil. Castor oil is unique among vegetable oil because it is the only commercial source of a ...

  14. Castor halls. A problem for the century; Castor-Hallen. Ein Jahrhundertproblem

    Energy Technology Data Exchange (ETDEWEB)

    Stay, Jochen

    2017-01-15

    The interim storage of high-level radioactive waste will last longer than asserted. The existing halls for the castor casks are not appropriate for this task with respect to safety. The casks themselves are not designed for long-term storage. Politics obviously do not consider the problems seriously.

  15. Reconnection in tokamaks

    International Nuclear Information System (INIS)

    Pare, V.K.

    1983-01-01

    Calculations with several different computer codes based on the resistive MHD equations have shown that (m = 1, n = 1) tearing modes in tokamak plasmas grow by magnetic reconnection. The observable behavior predicted by the codes has been confirmed in detail from the waveforms of signals from x-ray detectors and recently by x-ray tomographic imaging

  16. Research using small tokamaks

    International Nuclear Information System (INIS)

    1993-01-01

    This document consists of a collection of papers presented at the IAEA Technical Committee Meeting on Research Using Small Tokamaks. It contains 22 papers on a wide variety of research aspects, including diagnostics, design, transport, equilibrium, stability, and confinement. Some of these papers are devoted to other concepts (stellarators, compact tori). Refs, figs and tabs

  17. Research using small tokamaks

    International Nuclear Information System (INIS)

    1991-01-01

    The technical reports contained in this collection of papers on research using small tokamaks fall into four main categories, i.e., (i) experimental work (heating, stability, plasma radial profiles, fluctuations and transport, confinement, ultra-low-q tokamaks, wall physics, a.o.), (ii) diagnostics (beam probes, laser scattering, X-ray tomography, laser interferometry, electron-cyclotron absorption and emission systems), (iii) theory (strong turbulence, effects of heating on stability, plasma beta limits, wave absorption, macrostability, low-q tokamak configurations and bootstrap currents, turbulent heating, stability of vortex flows, nonlinear islands growth, plasma-drift-induced anomalous transport, ergodic divertor design, a.o.), and (iv) new technical facilities (varistors applied to establish constant current and loop voltage in HT-6M), lower-hybrid-current-drive systems for HT-6B and HT-6M, radio-frequency systems for HT-6M ICR heating experimentation, and applications of fiber optics for visible and vacuum ultraviolet radiation detection as applied to tokamaks and reversed-field pinches. A total number of 51 papers are included in the collection. Refs, figs and tabs

  18. 50 years of tokamaks

    Czech Academy of Sciences Publication Activity Database

    Mlynář, Jan; Řípa, Milan

    2008-01-01

    Roč. 2, č. 2 (2008), s. 7-7 ISSN 1818-5355 Institutional research plan: CEZ:AV0Z20430508 Keywords : Tokamak * history Subject RIV: BL - Plasma and Gas Discharge Physics http://www.efda.org/news_and_events/downloads/efda_newsletter/nl_2008_12.pdf

  19. Castor Oil Transesterification Catalysed by Liquid Enzymes

    DEFF Research Database (Denmark)

    Andrade, Thalles; Errico, Massimiliano; Christensen, Knud Villy

    2017-01-01

    In the present work, biodiesel production by reaction of non-edible castor oil with methanol under enzymatic catalysis is investigated. Two liquid enzymes were tested: Eversa Transform and Resinase HT. Reactions were performed at 35 °C and with a molar ratio of methanol to oil of 6:1. The reaction...... and fully reused; in the latter, a mixture of 50 % reused and 50 % fresh enzymes was tested. In the case of total reuse after three cycles, both enzymes achieved only low conversions. The biodiesel content in the oil-phase using Eversa Transform was 94.21 % for the first cycle, 68.39 % in the second, and 33...

  20. Tokamaks (Second Edition)

    International Nuclear Information System (INIS)

    Stott, Peter

    1998-01-01

    The first edition of John Wesson's book on tokamaks, published in 1987, established itself as essential reading for researchers in the field of magnetic confinement fusion: it was an excellent introduction for students to tokamak physics and also a valuable reference work for the more experienced. The second edition, published in 1997, has been completely rewritten and substantially enlarged (680 pages compared with 300). The new edition maintains the aim of providing a simple introduction to basic tokamak physics, but also includes discussion of the substantial advances in fusion research during the past decade. The new book, like its predecessor, is well written and commendable for its clarity and accuracy. In fact many of the chapters are written by a series of co-authors bringing the benefits of a wide range of expertise but, by careful editing, Wesson has maintained a uniformity of style and presentation. The chapter headings and coverage for the most part remain the same - but are expanded considerably and brought up to date. The most substantial change is that the single concluding chapter in the first edition on 'Experiments' has been replaced by three chapters: 'Tokamak experiments' which deals with some of the earlier key experiments plus a selection of recent small and medium-sized devices, 'Large experiments' which gives an excellent summary of the main results from the four large tokamaks - TFTR, JET, JT60/JT60U and DIII-D, and 'The future' which gives a very short (possibly too short in my opinion) account of reactors and ITER. This is an excellent book, which I strongly recommend should have a place - on the desk rather than in the bookshelf - of researchers in magnetic confinement fusion. (book review)

  1. Castor oil for induction of labour: a retrospective study.

    Science.gov (United States)

    Neri, Isabella; Dante, Giulia; Pignatti, Lucrezia; Salvioli, Chiara; Facchinetti, Fabio

    2018-08-01

    The aim of this study is to investigate the safety and efficacy of castor oil to induce labour. A retrospective observational case control study was conducted over five years. Castor oil was proposed to women referred to the Birth Centre (Castor Oil group (COG)). They were compared to women who chose to be followed by the traditional doctor-led unit (control group (CG)). Castor oil was administered in a 60 ml single dose in 200 ml of warm water. Inclusion criteria were gestational age between 40 and 41 weeks plus premature rupture of membranes between 12 and 18 hours or amniotic fluid index ≤4 or Bishop Score of ≤4 or absence of spontaneous labour over 41 + 4 weeks. Pharmacological induction of labour was required for 18 women in the COG (45%) and 36 in the CG (90%) (p castor oil showed a higher incidence of vaginal delivery, whereas the incidence of caesarean section was lower in the COG, but no statistical significance was reached. The use of castor oil is related to a higher probability of labour initiation within 24 hours. Castor oil can be considered a safe non-pharmacological method for labour induction.

  2. Large Aspect Ratio Tokamak Study

    International Nuclear Information System (INIS)

    Reid, R.L.; Holmes, J.A.; Houlberg, W.A.; Peng, Y.K.M.; Strickler, D.J.; Brown, T.G.; Wiseman, G.W.

    1980-06-01

    The Large Aspect Ratio Tokamak Study (LARTS) at Oak Ridge National Laboratory (ORNL) investigated the potential for producing a viable longburn tokamak reactor by enhancing the volt-second capability of the ohmic heating transformer through the use of high aspect ratio designs. The plasma physics, engineering, and economic implications of high aspect ratio tokamaks were assessed in the context of extended burn operation. Using a one-dimensional transport code plasma startup and burn parameters were addressed. The pulsed electrical power requirements for the poloidal field system, which have a major impact on reactor economics, were minimized by optimizing the startup and shutdown portions of the tokamak cycle. A representative large aspect ratio tokamak with an aspect ratio of 8 was found to achieve a burn time of 3.5 h at capital cost only approx. 25% greater than that of a moderate aspect ratio design tokamak

  3. Castor Oil Based Polyurethanes: Synthesis and Characterization

    Science.gov (United States)

    Macalino, AD; Salen, VA; Reyes, LQ

    2017-09-01

    In this study, polyurethanes based on castor oil and 1,6-hexamethylene diisocyanate (HMDI) were synthesized with varying weight ratio of the castor oil and HMDI. The formation of urethane linkages was verified through the use of a fourier transform infrared spectroscopy (FTIR). The hydrophilicity of the films was evaluated through the use of a contact angle meter and it was found that the contact angle of all the films were below 90 degrees which confirms their hydrophilicity. The thermal stability of the PU films were studies through the use of a thermal gravimetric analyzer and found that all of the polyurethane films exhibited two weight loss events at elevated temperatures wherein the first weight loss event was observed to occur at 285°C to 384°C while the second weight loss event was observed at around 521°C to 551°C. The hardness, elastic modulus, and tensile elongation of the PU films were determined by using a universal testing machine (UTM) where it was found out that the hardness and the elastic modulus of the film is directly proportional with HMDI loading while the tensile elongation is inversely proportional to it. Lastly, it was known through the swelling studies of the PU films that it does not swell, this is due to the presence of unreacted triglycerides in the material, which prevents water from permeating to the films.

  4. Tokamak fusion reactor exhaust

    International Nuclear Information System (INIS)

    Harrison, M.F.A.; Harbour, P.J.; Hotston, E.S.

    1981-08-01

    This report presents a compilation of papers dealing with reactor exhaust which were produced as part of the TIGER Tokamak Installation for Generating Electricity study at Culham. The papers are entitled: (1) Exhaust impurity control and refuelling. (2) Consideration of the physical problems of a self-consistent exhaust and divertor system for a long burn Tokamak. (3) Possible bundle divertors for INTOR and TIGER. (4) Consideration of various magnetic divertor configurations for INTOR and TIGER. (5) A appraisal of divertor experiments. (6) Hybrid divertors on INTOR. (7) Refuelling and the scrape-off layer of INTOR. (8) Simple modelling of the scrape-off layer. (9) Power flow in the scrape-off layer. (10) A model of particle transport within the scrape-off plasma and divertor. (11) Controlled recirculation of exhaust gas from the divertor into the scrape-off plasma. (U.K.)

  5. Density limits in Tokamaks

    International Nuclear Information System (INIS)

    Tendler, M.

    1984-06-01

    The energy loss from a tokamak plasma due to neutral hydrogen radiation and recycling is of great importance for the energy balance at the periphery. It is shown that the requirement for thermal equilibrium implies a constraint on the maximum attainable edge density. The relation to other density limits is discussed. The average plasma density is shown to be a strong function of the refuelling deposition profile. (author)

  6. Energy confinement in tokamaks

    International Nuclear Information System (INIS)

    Sugihara, M.; Singer, C.

    1986-08-01

    A straightforward generalization is made of the ohmic heating energy confinement scalings of Pfeiffer and Waltz and Blackwell et. al. The resulting model is systematically calibrated to published data from limiter tokamaks with ohmic, electron cyclotron, and neutral beam heating. With considerably fewer explicitly adjustable free parameters, this model appears to give a better fit to the available data for limiter discharges than the combined ohmic/auxiliary heating model of Goldston

  7. TPX tokamak construction management

    International Nuclear Information System (INIS)

    Knutson, D.; Kungl, D.; Seidel, P.; Halfast, C.

    1995-01-01

    A construction management contract normally involves the acquisition of a construction management firm to assist in the design, planning, budget conformance, and coordination of the construction effort. In addition the construction management firm acts as an agent in the awarding of lower tier contracts. The TPX Tokamak Construction Management (TCM) approach differs in that the construction management firm is also directly responsible for the assembly and installation of the tokamak including the design and fabrication of all tooling required for assembly. The Systems Integration Support (SIS) contractor is responsible for the architect-engineering design of ancillary systems, such as heating and cooling, buildings, modifications and site improvements, and a variety of electrical requirements, including switchyards and >4kV power distribution. The TCM will be responsible for the procurement of materials and the installation of the ancillary systems, which can either be performed directly by the TCM or subcontracted to a lower tier subcontractor. Assurance that the TPX tokamak is properly assembled and ready for operation when turned over to the operations team is the primary focus of the construction management effort. To accomplish this a disciplined constructability program will be instituted. The constructability effort will involve the effective and timely integration of construction expertise into the planning, component design, and field operations. Although individual component design groups will provide liaison during the machine assembly operations, the construction management team is responsible for assembly

  8. Time-resolved spectroscopy in the Rijnhuizen Tokamak Project tokamak

    NARCIS (Netherlands)

    Box, F. M. A.; Howard, J.; VandeKolk, E.; Meijer, F. G.

    1997-01-01

    At the Rijnhuizen Tokamak Project tokamak spectrometers are used to diagnose the velocity distribution and abundances of impurity ions. Quantities can be measured as a function of time, and the temporal resolution depends on the line emissivity and can be as good as 0.2 ms for the strongest lines.

  9. Modified Castor Oil as an Epoxy Resin Curing Agent

    Directory of Open Access Journals (Sweden)

    B. P. Patel

    2004-01-01

    Full Text Available A castor oil, an agricultural product, is an unsaturated material. Hence the castor oil is brominated by bromine liquid. The brominated castor oil (BCO was then reacted with excess of aliphatic diamines viz; ethylene diamine, 1,3-propane diamine and 1,6-hexane diamine. The resultant amino functionalized castor oil (ACO samples were then characterized by elemental analysis, IR spectral study and number of amino groups. All the three ACO samples were then employed for the curing of commercial Brominated epoxy resin. The curing of epoxy resin by ACO was monitored on differential scanning calorimeter (DSC and based on the DSC study their glass fibre reinforced composites (GRC were fabricated. The cured samples (i.e. unreinforced were also subjected to thermo gravimetric analysis (TGA. The chemical, mechanical and electrical properties of the glass fibre reinforced composites (GRC were also evaluated.

  10. Production of Detergent from Castor Oil

    Directory of Open Access Journals (Sweden)

    Abubakar Garba ISAH

    2006-07-01

    Full Text Available This research work was carried out with the objective of extraction of oil from castor seeds and its utilization to produce a synthetic detergent. Solvent extraction method was employed in extracting the oil and the total percent oil yield was found to be 23.8%. The experimentally determined saponification value of the oil was 183.7275mgKOH/g of oil. The detergent efficiency, determined as a measure of the foamability of the detergent was found to be 2.6cm. The pH tests revealed mildly basic properties. The color, scent and efficiency of the detergent were improved with the addition of bleaching agent, perfume and foaming agents respectively.

  11. The Castor 120 (TM) motor: Development and qualification testing results

    Science.gov (United States)

    Hilden, Jack G.; Poirer, Beverly M.

    1993-01-01

    This paper discusses Thiokol Corporation's static test results for the development and qualification program of the Castor 120(TM) motor. The demonstration program began with a 25,000-pound motor to demonstrate the new technologies and processes that would be used on the larger Castor 120(TM) motor. The Castor 120(TM) motor was designed to be applicable as a first stage, second stage, or strap-on motor. Static test results from the Castor 25 and two Castor 120(TM) motors are discussed in this paper. The results verified the feasibility of tailoring the propellant grain configuration and nozzle throat diameter to meet various customer requirements. The first and second motors were conditioned successfully at ambient temperature and 28 F, respectively, to demonstrate that the design could handle a wide range of environmental launch conditions. Furthermore, the second Castor 120(TM) motor demonstrated a systems tunnel and forward skirt extension to verify flight-ready stage hardware. It is anticipated that the first flight motor will be ready by the fall of 1994.

  12. Magnetic confinement experiment -- 1: Tokamaks

    International Nuclear Information System (INIS)

    Goldston, R.J.

    1994-01-01

    This report reviews presentations made at the 15th IAEA Conference on Plasma Physics and Controlled Nuclear Fusion on experimental tokamak physics, particularly on advances in core plasma physics, divertor and edge physics, heating and current drive, and tokamak concept optimization

  13. The density limit in Tokamaks

    International Nuclear Information System (INIS)

    Alladio, F.

    1985-01-01

    A short summary of the present status of experimental observations, theoretical ideas and understanding of the density limit in tokamaks is presented. It is the result of the discussion that was held on this topic at the 4th European Tokamak Workshop in Copenhagen (December 4th to 6th, 1985). 610 refs

  14. Multifractal analysis of plasma turbulence in biasing experiments on Castor tokamak

    Czech Academy of Sciences Publication Activity Database

    Budaev, V.P.; Dufková, Edita; Nanobashvili, S.; Weinzettl, Vladimír; Zajac, Jaromír

    2005-01-01

    Roč. 55, C (2005), s. 1615-1621 ISSN 0011-4626. [Workshop “Electric Fields, Structures and Relaxation in Edge Plasmas". Tarragona, 5.7.2005-5.7.2005] Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma turbulence * multifractal analysis Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.360, year: 2005

  15. Tokamaks - Third Edition

    International Nuclear Information System (INIS)

    Rogister, A L

    2004-01-01

    John Wesson's well known book, now re-edited for the third time, provides an excellent introduction to fusion oriented plasma physics in tokamaks. The author's task was a very challenging one, for a confined plasma is a complex system characterised by a variety of dimensionless parameters and its properties change qualitatively when certain threshold values are reached in this multi-parameter space. As a consequence, theoretical description is required at different levels, which are complementary: particle orbits, kinetic and fluid descriptions, but also intuitive and empirical approaches. Theory must be carried out on many fronts: equilibrium, instabilities, heating, transport etc. Since the properties of the confined plasma depend on the boundary conditions, the physics of plasmas along open magnetic field lines and plasma surface interaction processes must also be accounted for. Those subjects (and others) are discussed in depth in chapters 2-9. Chapter 1 mostly deals with ignition requirements and the tokamak concept, while chapter 14 provides a list of useful relations: differential operators, collision times, characteristic lengths and frequencies, expressions for the neoclassical resistivity and heat conduction, the bootstrap current etc. The presentation is sufficiently broad and thorough that specialists within tokamak research can either pick useful and up-to-date information or find an authoritative introduction into other areas of the subject. It is also clear and concise so that it should provide an attractive and accurate initiation for those wishing to enter the field and for outsiders who would like to understand the concepts and be informed about the goals and challenges on the horizon. Validation of theoretical models requires adequately resolved experimental data for the various equilibrium profiles (clearly a challenge in the vicinity of transport barriers) and the fluctuations to which instabilities give rise. Chapter 10 is therefore devoted to

  16. Nonlinear gyrokinetic tokamak physics

    International Nuclear Information System (INIS)

    Brizard, A.J.

    1990-01-01

    The gyrokinetic reduced description of low-frequency and small-perpendicular-wavelength nonlinear tokamak dynamics is presented in three different versions: the reduced dynamical description of test particles moving in electromagnetic fields; the reduced gyrokinetic description of the self-consistent interaction of particles and fields through the Maxwell-Vlasov equations; and the reduced description of nonlinear fluid motion. The unperturbed tokamak plasma is described in terms of a noncanonical Hamiltonian guiding-center theory. The unperturbed guiding-center tokamak plasma is then perturbed by gyrokinetic electromagnetic fields and consequently the perturbed guiding-center dynamical system acquires new gyrophase dependence. The perturbation analysis that follows makes extensive use of Lie-transform perturbation techniques. Because the electromagnetic perturbations affect both the Hamiltonian and the Poisson-bracket structure, the Phase-space Lagrangian Lie perturbation method is used. The description of the reduced test-particle dynamics is given in terms of a non-canonical Hamiltonian gyrocenter theory. The description of the reduced kinetic dynamics is concerned with the self consistent response of the guiding-center plasma and is described in terms of the nonlinear gyrokinetic Maxwell-Vlasov equations. It is also shown that the gyrokinetic Maxwell-Vlasov system possesses a gyrokinetic energy adiabatic invariant and that, in both the linear and nonlinear (quadratic) approximations, the corresponding energy invariants are exact. The description of the reduced fluid dynamics is concerned with the derivation of a closed set of reduced fluid equations. Three generations of reduced fluid models are presented: the reduced MHD equations; the reduced FLR-MHD equations; and the gyrofluid equations

  17. Tokamak instrumentation and controls

    Energy Technology Data Exchange (ETDEWEB)

    Becraft, W. R.; Bettis, E. S.; Houlberg, W. A.; Onega, R. J.; Stone, R. S.

    1979-02-01

    The three areas of study emphasis to date are: (1) Physics implications for controls, (2) Computer simulation, and (3) Shutdown/aborts. This document reports on the FY 78 efforts (the first year of these studies) to address these problems. Transient scenario options for the startup of a tokamak are developed, and the implications for the control system are discussed. This document also presents a hybrid computer simulation (analog and digital) of the Impurity Study Experiment (ISX-B) which is now being used for corroborative controls investigations. The simulation will be expanded to represent a TNS/ETF machine.

  18. Demonstration tokamak power plant

    Energy Technology Data Exchange (ETDEWEB)

    Abdou, M.; Baker, C.; Brooks, J.; Ehst, D.; Mattas, R.; Smith, D.L.; DeFreece, D.; Morgan, G.D.; Trachsel, C.

    1983-01-01

    A conceptual design for a tokamak demonstration power plant (DEMO) was developed. A large part of the study focused on examining the key issues and identifying the R and D needs for: (1) current drive for steady-state operation, (2) impurity control and exhaust, (3) tritium breeding blanket, and (4) reactor configuration and maintenance. Impurity control and exhaust will not be covered in this paper but is discussed in another paper in these proceedings, entitled Key Issues of FED/INTOR Impurity Control System.

  19. Tokamak instrumentation and controls

    International Nuclear Information System (INIS)

    Becraft, W.R.; Bettis, E.S.; Houlberg, W.A.; Onega, R.J.; Stone, R.S.

    1979-02-01

    The three areas of study emphasis to date are: (1) Physics implications for controls, (2) Computer simulation, and (3) Shutdown/aborts. This document reports on the FY 78 efforts (the first year of these studies) to address these problems. Transient scenario options for the startup of a tokamak are developed, and the implications for the control system are discussed. This document also presents a hybrid computer simulation (analog and digital) of the Impurity Study Experiment (ISX-B) which is now being used for corroborative controls investigations. The simulation will be expanded to represent a TNS/ETF machine

  20. The TFR-600 Tokamak

    International Nuclear Information System (INIS)

    1977-11-01

    The new step of the Tokamak TFR, TFR 600, is described with its different aspects: physical objectives, modifications of the vacuum chamber and of the poloidal circuit, additionnal heatings. The nominal characteristics are: R=98 cm; a 0 or D 0 at 40 keV (power transmitted to the plasma); - ion cyclotron radiofrequency heating: 600 kW in the bandwidth 55-83 MHz; - and cluster injection: 100 KW at 600 keV (average mass of the H 0 clusters: 100-200 A.MU) [fr

  1. Maximum entropy tokamak configurations

    International Nuclear Information System (INIS)

    Minardi, E.

    1989-01-01

    The new entropy concept for the collective magnetic equilibria is applied to the description of the states of a tokamak subject to ohmic and auxiliary heating. The condition for the existence of steady state plasma states with vanishing entropy production implies, on one hand, the resilience of specific current density profiles and, on the other, severe restrictions on the scaling of the confinement time with power and current. These restrictions are consistent with Goldston scaling and with the existence of a heat pinch. (author)

  2. Tokamak burn control

    International Nuclear Information System (INIS)

    Sager, G.T.

    1988-06-01

    Research of the fusion plasma thermal instability and its control is reviewed. General models of the thermonuclear plasma are developed. Techniques of stability analysis commonly employed in burn control research are discussed. Methods for controlling the plasma against the thermal instability are reviewed. Emphasis is placed on applications to tokamak confinement concepts. Additional research which extends the results of previous research is suggested. Issues specific to the development of control strategies for mid-term engineering test reactors are identified and addressed. 100 refs., 24 figs., 10 tabs

  3. Discovery and Characterization of Novel Signatures from the Ricinus communis L. (Castor Bean) Genome

    National Research Council Canada - National Science Library

    O'Connell, Kevin P; Skowronski, Evan W; Dretchen, Kenneth L; Leshin, Jonathan A; Weeks, Andrea

    2006-01-01

    Given the infamous toxicity of ricin and the industrial usefulness of castor oil, there is a surprising lack of information about the genetic diversity of the species that produces both, the castor bean plant (Ricinus communis L...

  4. Castor Oil: Properties, Uses, and Optimization of Processing Parameters in Commercial Production.

    Science.gov (United States)

    Patel, Vinay R; Dumancas, Gerard G; Kasi Viswanath, Lakshmi C; Maples, Randall; Subong, Bryan John J

    2016-01-01

    Castor oil, produced from castor beans, has long been considered to be of important commercial value primarily for the manufacturing of soaps, lubricants, and coatings, among others. Global castor oil production is concentrated primarily in a small geographic region of Gujarat in Western India. This region is favorable due to its labor-intensive cultivation method and subtropical climate conditions. Entrepreneurs and castor processors in the United States and South America also cultivate castor beans but are faced with the challenge of achieving high castor oil production efficiency, as well as obtaining the desired oil quality. In this manuscript, we provide a detailed analysis of novel processing methods involved in castor oil production. We discuss novel processing methods by explaining specific processing parameters involved in castor oil production.

  5. Castor oil for induction of labour: not harmful, not helpful.

    Science.gov (United States)

    Boel, Machteld Elisabeth; Lee, Sue Jean; Rijken, Marcus Johannes; Paw, Moo Koo; Pimanpanarak, Mupawjay; Tan, Saw Oo; Singhasivanon, Pratap; Nosten, François; McGready, Rose

    2009-10-01

    Castor oil is one of the most popular drugs for induction of labour in a non-medical setting; however, published data on safety and effectiveness of this compound to induce labour remain sparse. To assess the safety and effectiveness of castor oil for induction of labour in pregnancies with an ultrasound estimated gestational at birth of more than 40 weeks. Data were extracted from hospital-based records of all pregnant women who attended antenatal clinics on the Thai-Burmese border and who were more than 40 weeks pregnant. The effectiveness of castor oil to induce labour was expressed as time to birth and analysed with a Cox proportional hazards regression model. Measures associated with safety were fetal distress, meconium-stained amniotic fluid, tachysystole of the uterus, uterine rupture, abnormal maternal blood pressure during labour, Apgar scores, neonatal resuscitation, stillbirth, post-partum haemorrhage, severe diarrhoea and maternal death. Proportions were compared using Fisher's exact test. Of 612 women with a gestation of more than 40 weeks, 205 received castor oil for induction and 407 did not. The time to birth was not significantly different between the two groups (hazard ratio 0.99 (95% confidence interval: 0.81 to 1.20; n = 509)). Castor oil use was not associated with any harmful effects on the mother or fetus. Castor oil for induction of labour had no effect on time to birth nor were there any harmful effects observed in this large series. Our findings leave no justification for recommending castor oil for this purpose.

  6. Castor Oil: Properties, Uses, and Optimization of Processing Parameters in Commercial Production

    OpenAIRE

    Patel, Vinay R.; Dumancas, Gerard G.; Kasi Viswanath, Lakshmi C.; Maples, Randall; Subong, Bryan John J.

    2016-01-01

    Castor oil, produced from castor beans, has long been considered to be of important commercial value primarily for the manufacturing of soaps, lubricants, and coatings, among others. Global castor oil production is concentrated primarily in a small geographic region of Gujarat in Western India. This region is favorable due to its labor-intensive cultivation method and subtropical climate conditions. Entrepreneurs and castor processors in the United States and South America also cultivate cast...

  7. Castor oil induces laxation and uterus contraction via ricinoleic acid activating prostaglandin EP3 receptors

    OpenAIRE

    Tunaru, Sorin; Althoff, Till F.; Nüsing, Rolf M.; Diener, Martin; Offermanns, Stefan

    2012-01-01

    Castor oil is one of the oldest drugs. When given orally, it has a laxative effect and induces labor in pregnant females. The effects of castor oil are mediated by ricinoleic acid, a hydroxylated fatty acid released from castor oil by intestinal lipases. Despite the wide-spread use of castor oil in conventional and folk medicine, the molecular mechanism by which ricinoleic acid acts remains unknown. Here we show that the EP3 prostanoid receptor is specifically activated by ricinoleic acid and...

  8. Axisymmetric control in tokamaks

    International Nuclear Information System (INIS)

    Humphreys, D.A.

    1991-02-01

    Vertically elongated tokamak plasmas are intrinsically susceptible to vertical axisymmetric instabilities as a result of the quadrupole field which must be applied to produce the elongation. The present work analyzes the axisymmetric control necessary to stabilize elongated equilibria, with special application to the Alcator C-MOD tokamak. A rigid current-conserving filamentary plasma model is applied to Alcator C-MOD stability analysis, and limitations of the model are addressed. A more physically accurate nonrigid plasma model is developed using a perturbed equilibrium approach to estimate linearized plasma response to conductor current variations. This model includes novel flux conservation and vacuum vessel stabilization effects. It is found that the nonrigid model predicts significantly higher growth rates than predicted by the rigid model applied to the same equilibria. The nonrigid model is then applied to active control system design. Multivariable pole placement techniques are used to determine performance optimized control laws. Formalisms are developed for implementing and improving nominal feedback laws using the C-MOD digital-analog hybrid control system architecture. A proportional-derivative output observer which does not require solution of the nonlinear Ricatti equation is developed to help accomplish this implementation. The nonrigid flux conserving perturbed equilibrium plasma model indicates that equilibria with separatrix elongation of at least κ sep = 1.85 can be stabilized robustly with the present control architecture and conductor/sensor configuration

  9. Topology of tokamak orbits

    International Nuclear Information System (INIS)

    Rome, J.A.; Peng, Y.K.M.

    1978-09-01

    Guiding center orbits in noncircular axisymmetric tokamak plasmas are studied in the constants of motion (COM) space of (v, zeta, psi/sub m/). Here, v is the particle speed, zeta is the pitch angle with respect to the parallel equilibrium current, J/sub parallels/, and psi/sub m/ is the maximum value of the poloidal flux function (increasing from the magnetic axis) along the guiding center orbit. Two D-shaped equilibria in a flux-conserving tokamak having β's of 1.3% and 7.7% are used as examples. In this space, each confined orbit corresponds to one and only one point and different types of orbits (e.g., circulating, trapped, stagnation and pinch orbits) are represented by separate regions or surfaces in the space. It is also shown that the existence of an absolute minimum B in the higher β (7.7%) equilibrium results in a dramatically different orbit topology from that of the lower β case. The differences indicate the confinement of additional high energy (v → c, within the guiding center approximation) trapped, co- and countercirculating particles whose orbit psi/sub m/ falls within the absolute B well

  10. ITER tokamak device

    International Nuclear Information System (INIS)

    Doggett, J.; Salpietro, E.; Shatalov, G.

    1991-01-01

    The results of the Conceptual Design Activities for the International Thermonuclear Experimental Reactor (ITER) are summarized. These activities, carried out between April 1988 and December 1990, produced a consistent set of technical characteristics and preliminary plans for co-ordinated research and development support of ITER; and a conceptual design, a description of design requirements and a preliminary construction schedule and cost estimate. After a description of the design basis, an overview is given of the tokamak device, its auxiliary systems, facility and maintenance. The interrelation and integration of the various subsystems that form the ITER tokamak concept are discussed. The 16 ITER equatorial port allocations, used for nuclear testing, diagnostics, fuelling, maintenance, and heating and current drive, are given, as well as a layout of the reactor building. Finally, brief descriptions are given of the major ITER sub-systems, i.e., (i) magnet systems (toroidal and poloidal field coils and cryogenic systems), (ii) containment structures (vacuum and cryostat vessels, machine gravity supports, attaching locks, passive loops and active coils), (iii) first wall, (iv) divertor plate (design and materials, performance and lifetime, a.o.), (v) blanket/shield system, (vi) maintenance equipment, (vii) current drive and heating, (viii) fuel cycle system, and (ix) diagnostics. 11 refs, figs and tabs

  11. Canonical profiles in tokamaks

    International Nuclear Information System (INIS)

    Dnestrovskij, Yu.N.

    2002-01-01

    We consider the problem of the canonical profiles for tokamak plasma with arbitrary cross-section, taking into account two principles: 1) the free plasma energy minimum with the constraint of total current conservation and 2) the profile consistency. We deduce the Euler differential equation for the canonical profile of μ=1/q with two types of the boundary conditions: soft and stiff. The soft conditions correspond to the Kadomtsev solution for the circular cylinder. The stiff conditions describe a fast response of the plasma over the whole cross-section on the edge impact. Using the canonical profile of the current density, we calculate the critical gradients for the temperature, and create the transport model for the electron and ion temperatures and density. We show that, when the aspect ratio is diminished, or when the elongation increases, the canonical profiles become flatten. The similar tendency for the real profiles of the electron temperature was found in analysis of JET and START experiments. The obtained critical gradients were used to analysis of the experiments in tokamaks with moderate and tight aspect ratios. (author)

  12. 21 CFR 524.2620 - Liquid crystalline trypsin, Peru balsam, castor oil.

    Science.gov (United States)

    2010-04-01

    ... NEW ANIMAL DRUGS § 524.2620 Liquid crystalline trypsin, Peru balsam, castor oil. (a)(1) Specifications..., and 788.0 milligrams of castor oil. (2) Sponsor. See No. 051079 in § 510.600(c) of this chapter. (b)(1... balsam, and 800 milligrams of castor oil. (2) Sponsor. See No. 017135 in § 510.600(c) of this chapter. (c...

  13. Castor oil biodiesel as an alternative fuel for diesel engines

    International Nuclear Information System (INIS)

    Benavides, Alirio; Benjumea, Pedro; Pashova, Veselina

    2007-01-01

    In this paper, a study related to the production and use of castor oil biodiesel is presented. The maximum methyl esters yield of the castor oil transesterification reaction is obtained under the following conditions: ambient temperature, a molar ratio of methanol to vegetable oil equal to 9 and a catalyst percentage equal to 0.8%. The castor oil biodiesel can be blended with petroleum diesel as far as 15% in such way that the resulting blend complies with national and international technical standards for diesel fuels. Its high viscosity becomes the main difficulty for using castor oil biodiesel in engines. However this biofuel exhibits excellent cold flow properties (low values of cloud and pour points). The motor tests using castor oil biodiesel petroleum diesel blends, for the biodiesel proportion tested; show that a biodiesel percentage increase leads to an increase in the specific fuel consumption, a decrease in the fuel air ratio, a slight decrease in smoke opacity, while the fuel conversion efficiency and the CO and CO 2 emissions practically remain constants

  14. JUST: Joint Upgraded Spherical Tokamak

    International Nuclear Information System (INIS)

    Azizov, E.A.; Dvorkin, N.Ya.; Filatov, O.G.

    1997-01-01

    The main goals, ideas and the programme of JUST, spherical tokamak (ST) for the plasma burn investigation, are presented. The place and prospects of JUST in thermonuclear investigations are discussed. (author)

  15. Preliminary Design of Alborz Tokamak

    Science.gov (United States)

    Mardani, M.; Amrollahi, R.; Saramad, S.

    2012-04-01

    The Alborz tokamak is a D-shape cross section tokamak that is under construction in Amirkabir University of Technology. The most important part of the tokamak design is the design of TF coils. In this paper a refined design of the TF coil system for the Alborz tokamak is presented. This design is based on cooper cable conductor with 5 cm width and 6 mm thickness. The TF coil system is consist of 16 rectangular shape coils, that makes the magnetic field of 0.7 T at the plasma center. The stored energy in total is 160 kJ, and the power supply used in this system is a capacitor bank with capacity of C = 1.32 mF and V max = 14 kV.

  16. Alcator C-Mod Tokamak

    Data.gov (United States)

    Federal Laboratory Consortium — Alcator C-Mod at the Massachusetts Institute of Technology is operated as a DOE national user facility. Alcator C-Mod is a unique, compact tokamak facility that uses...

  17. Spherical tokamak development in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, G.O.; Del Bosco, E.; Ferreira, J.G.; Berni, L.A.; Oliveira, R.M.; Andrade, M.C.R.; Shibata, C.S.; Ueda, M.; Barroso, J.J.; Castro, P.J. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Lab. Associado de Plasma; Barbosa, L.F.W. [Universidade do Vale do Paraiba (UNIVAP), Sao Jose dos Campos, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo; Patire Junior, H. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Div. de Mecanica Espacial e Controle; The high-power microwave sources group

    2003-12-01

    This paper describes the general characteristics of spherical tokamaks, or spherical tori, with a brief overview of work in this area already performed or in progress at several institutions worldwide. The paper presents also the steps in the development of the ETE (Experimento Tokamak Esferico) project, its research program, technical characteristics and operating conditions as of December, 2002 at the Associated Plasma Laboratory (LAP) of the National Space Research Institute (INPE) in Brazil. (author)

  18. Spherical tokamak development in Brazil

    International Nuclear Information System (INIS)

    Ludwig, G.O.; Del Bosco, E.; Ferreira, J.G.; Berni, L.A.; Oliveira, R.M.; Andrade, M.C.R.; Shibata, C.S.; Ueda, M.; Barroso, J.J.; Castro, P.J.; Barbosa, L.F.W.; Patire Junior, H.; The high-power microwave sources group

    2003-01-01

    This paper describes the general characteristics of spherical tokamaks, or spherical tori, with a brief overview of work in this area already performed or in progress at several institutions worldwide. The paper presents also the steps in the development of the ETE (Experimento Tokamak Esferico) project, its research program, technical characteristics and operating conditions as of December, 2002 at the Associated Plasma Laboratory (LAP) of the National Space Research Institute (INPE) in Brazil. (author)

  19. Spherical tokamak development in Brazil

    International Nuclear Information System (INIS)

    Ludwig, Gerson Otto; Bosco, Edson Del; Ferreira, Julio Guimaraes

    2003-01-01

    The general characteristics of spherical tokamaks, or spherical tori, with a brief view of work in this area already performed or in progress at several institutions worldwide are described. The paper presents also the steps in the development of the ETE (Experiment Tokamak spheric) project, its research program, technical characteristics and operating conditions as of December, 2002 a the Associated Plasma Laboratory (LAP) of the National Space Research Institute (INPE) in Brazil. (author)

  20. Spherical tokamak development in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Gerson Otto; Bosco, Edson Del; Ferreira, Julio Guimaraes [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Lab. Associado de Plasma] (and others)

    2003-07-01

    The general characteristics of spherical tokamaks, or spherical tori, with a brief view of work in this area already performed or in progress at several institutions worldwide are described. The paper presents also the steps in the development of the ETE (Experiment Tokamak spheric) project, its research program, technical characteristics and operating conditions as of December, 2002 a the Associated Plasma Laboratory (LAP) of the National Space Research Institute (INPE) in Brazil. (author)

  1. Confinement and diffusion in tokamaks

    International Nuclear Information System (INIS)

    McWilliams, R.

    1988-01-01

    The effect of electric field fluctuations on confinement and diffusion in tokamak is discussed. Based on the experimentally determined cross-field turbolent diffusion coefficient, D∼3.7*cT e /eB(δn i /n i ) rms which is also derived by a simple theory, the cross-field diffusion time, tp=a 2 /D, is calculated and compared to experimental results from 51 tokamak for standard Ohmic operation

  2. The ETE spherical Tokamak project

    International Nuclear Information System (INIS)

    Ludwig, Gerson Otto; Andrade, Maria Celia Ramos de; Barbosa, Luis Filipe Wiltgen

    1999-01-01

    This paper describes the general characteristics of spherical tokamaks, with a brief overview of work in the area of spherical torus already performed or in progress at several institutions. The paper presents also the historical development of the ETE (Spherical Tokamak Experiment) project, its research program, technical characteristics and status of construction in September, 1998 at the Associated plasma Laboratory (LAP) of the National Institute for Space Research (INPE) in Brazil. (author)

  3. The ETE spherical Tokamak project

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Gerson Otto; Andrade, Maria Celia Ramos de; Barbosa, Luis Filipe Wiltgen [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Lab. Associado de Plasma] [and others]. E-mail: ludwig@plasma.inpe.br

    1999-07-01

    This paper describes the general characteristics of spherical tokamaks, with a brief overview of work in the area of spherical torus already performed or in progress at several institutions. The paper presents also the historical development of the ETE (Spherical Tokamak Experiment) project, its research program, technical characteristics and status of construction in September, 1998 at the Associated plasma Laboratory (LAP) of the National Institute for Space Research (INPE) in Brazil. (author)

  4. The Compact Ignition Tokamak

    International Nuclear Information System (INIS)

    Schmidt, J.

    1987-01-01

    The author discusses his lab's plan for completing the Compact Ignition Tokamak (CIT) conceptual design during calendar year 1987. Around July 1 they froze the subsystem envelopes on the device to continue with the conceptual design. They did this by formalizing a general requirements document. They have been developing the management plan and submitted a version to the DOE July 10. He describes a group of management activities. They released the vacuum vessel Request For Proposals (RFP) on August 5. An RFP to do a major part of the system engineering on the device is being developed. They intend to assemble the device outside of the test cell, then move it into the the test cell, install it there, and bring to the test cell many of the auxiliary facilities from TFTR, for example, power supplies

  5. Plasma turbulence in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Caldas, Ibere L.; Heller, M.V.A.P.; Brasilio, Z.A. [Sao Paulo Univ., SP, RJ (Brazil). Inst. de Fisica

    1997-12-31

    Full text. In this work we summarize the results from experiments on electrostatic and magnetic fluctuations in tokamak plasmas. Spectral analyses show that these fluctuations are turbulent, having a broad spectrum of wavectors and a broad spectrum of frequencies at each wavector. The electrostatic turbulence induces unexpected anomalous particle transport that deteriorates the plasma confinement. The relationship of these fluctuations to the current state of plasma theory is still unclear. Furthermore, we describe also attempts to control this plasma turbulence with external magnetic perturbations that create chaotic magnetic configurations. Accordingly, the magnetic field lines may become chaotic and then induce a Lagrangian diffusion. Moreover, to discuss nonlinear coupling and intermittency, we present results obtained by using numerical techniques as bi spectral and wavelet analyses. (author)

  6. The Varennes tokamak

    International Nuclear Information System (INIS)

    Gregory, B.C.; Bolton, R.A.; Pacher, H.D.

    1983-01-01

    This article is a progress report on the Varennes Tokamak (TdeV), which is the main element in the Canadian research program on magnetic confinement fusion. The project is led by a group of five institutions: the Hydro-Quebec Research Institute (IREQ), the National Research Council - Energy, the University of Montreal, CANATOM Ltd., and MPB Technologies Inc. The TdeV will cost about 40 million dollars and will be built in a large hall at the IREQ high energy laboratory in Varennes. Operation in a quasi-stationary regime has been adopted as one of the primary research areas for the TdeV. First plasma is expected at the end of 1984 [fr

  7. High Beta Tokamak research

    International Nuclear Information System (INIS)

    Navratil, G.A.; Mauel, M.E.; Ivers, T.H.; Sankar, M.K.V.; Eisner, E.; Gates, D.; Garofalo, A.; Kombargi, R.; Maurer, D.; Nadle, D.; Xiao, Q.

    1993-01-01

    During the past 6 months, experiments have been conducted with the HBT-EP tokamak in order to (1) test and evaluate diagnostic systems, (2) establish basic machine operation, (3) document MHD behavior as a function of global discharge parameters, (4) investigate conditions leading to passive stabilization of MHD instabilities, and (5) quantify the external saddle coil current required for DC mode locking. In addition, the development and installation of new hardware systems has occurred. A prototype saddle coil was installed and tested. A five-position (n,m) = (1,2) external helical saddle coil was attached for mode-locking experiments. And, fabrication of the 32-channel UV tomography and the multipass Thomson scattering diagnostics have begun in preparation for installation later this year

  8. Tokamak hybrid study

    International Nuclear Information System (INIS)

    Tenney, F.H.

    1976-09-01

    A report on one year of study of a tokamak hybrid reactor is presented. The plasma is maintained by both D and T beams. To obtain long burn times a poloidal field divertor is required. Both the single null and the double null style of divertor are considered. The blanket consists of a neutron multiplier region containing natural uranium followed by burner regions of molten salt (flibe) loaded with PuF 3 to enhance the energy multiplication. Economic analysis has been applied only recently to a variety of reactor sizes and plasma conditions. Early indications suggest that the most attractive hybrids will have large plasmas of major radius in excess of 8 meters

  9. Tokamak hybrid study

    International Nuclear Information System (INIS)

    Tenney, F.H.

    1976-01-01

    A report on one year of study of a tokamak hybrid reactor is given. The plasma is maintained by both D and T beams. To obtain long burn times a poloidal field divertor is required. Both the single null and the double null style of divertor are considered. The blanket consists of a neutron multiplier region containing natural uranium followed by burner regions of molten salt (flibe) loaded with PuF 3 to enhance the energy multiplication. Economic analysis has been applied only recently to a variety of reactor sizes and plasma conditions. Early indications suggest that the most attractive hybrids will have large plasmas of major radius in excess of 8 meters

  10. Heterogeneous catalysis afford biodiesel of babassu, castor oil and blends

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Lee M.G. de; Abreu, Wiury C. de; Silva, Maria das Gracas de O. e; Matos, Jose Milton E. de; Moura, Carla V.R. de; Moura, Edmilson M. de, E-mail: mmoura@ufpi.edu.br [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil). Departamento de Quimica; Lima, Jose Renato de O.; Oliveira, Jose Eduardo de [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP/IQ/CEMPEQC), Araraquara, SP (Brazil). Instituto de Quimica. Centro de Monitoramento e Pesquisa da Qualidade de Combustiveis, Biocombustiveis, Petroleo e Derivados

    2013-04-15

    This work describes the preparation of babassu, castor oil biodiesel and mixtures in various proportions of these oils, using alkaline compounds of strontium (SrCO{sub 3} + SrO + Sr (OH){sub 2}) as heterogeneous catalysts. The mixture of oils of these oleaginous sources was used in the production of biodiesel with quality parameters that meet current legislation. The catalyst was characterized by X-ray diffractometry (XDR), physisorption of gas (BET method), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). The viscometric technique was used to monitor the optimization.The transesterification reactions performed using strontium compounds reached conversion rates of 97.2% babassu biodiesel (BB), 96.4% castor oil biodiesel (COB) and 95.3% Babassu/Castor Oil Biodiesel 4:1 (BBCO41). (author)

  11. Heterogeneous catalysis afford biodiesel of babassu, castor oil and blends

    International Nuclear Information System (INIS)

    Carvalho, Lee M.G. de; Abreu, Wiury C. de; Silva, Maria das Gracas de O. e; Matos, Jose Milton E. de; Moura, Carla V.R. de; Moura, Edmilson M. de; Lima, Jose Renato de O.; Oliveira, Jose Eduardo de

    2013-01-01

    This work describes the preparation of babassu, castor oil biodiesel and mixtures in various proportions of these oils, using alkaline compounds of strontium (SrCO 3 + SrO + Sr (OH) 2 ) as heterogeneous catalysts. The mixture of oils of these oleaginous sources was used in the production of biodiesel with quality parameters that meet current legislation. The catalyst was characterized by X-ray diffractometry (XDR), physisorption of gas (BET method), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). The viscometric technique was used to monitor the optimization.The transesterification reactions performed using strontium compounds reached conversion rates of 97.2% babassu biodiesel (BB), 96.4% castor oil biodiesel (COB) and 95.3% Babassu/Castor Oil Biodiesel 4:1 (BBCO41). (author)

  12. The ARIES tokamak reactor study

    International Nuclear Information System (INIS)

    1989-10-01

    The ARIES study is a community effort to develop several visions of tokamaks as fusion power reactors. The aims are to determine the potential economics, safety, and environmental features of a range of possible tokamak reactors, and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Three ARIES visions are planned, each having a different degree of extrapolation from the present data base in physics and technology. The ARIES-I design assumes a minimum extrapolation from current tokamak physics (e.g., 1st stability) and incorporates technological advances that can be available in the next 20 to 30 years. ARIES-II is a DT-burning tokamak which would operate at a higher beta in the 2nd MHD stability regime. It employs both potential advances in the physics and expected advances in technology and engineering. ARIES-II will examine the potential of the tokamak and the D 3 He fuel cycle. This report is a collection of 14 papers on the results of the ARIES study which were presented at the IEEE 13th Symposium on Fusion Engineering (October 2-6, 1989, Knoxville, TN). This collection describes the ARIES research effort, with emphasis on the ARIES-I design, summarizing the major results, the key technical issues, and the central conclusions

  13. The ARIES tokamak reactor study

    Energy Technology Data Exchange (ETDEWEB)

    1989-10-01

    The ARIES study is a community effort to develop several visions of tokamaks as fusion power reactors. The aims are to determine the potential economics, safety, and environmental features of a range of possible tokamak reactors, and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Three ARIES visions are planned, each having a different degree of extrapolation from the present data base in physics and technology. The ARIES-I design assumes a minimum extrapolation from current tokamak physics (e.g., 1st stability) and incorporates technological advances that can be available in the next 20 to 30 years. ARIES-II is a DT-burning tokamak which would operate at a higher beta in the 2nd MHD stability regime. It employs both potential advances in the physics and expected advances in technology and engineering. ARIES-II will examine the potential of the tokamak and the D{sup 3}He fuel cycle. This report is a collection of 14 papers on the results of the ARIES study which were presented at the IEEE 13th Symposium on Fusion Engineering (October 2-6, 1989, Knoxville, TN). This collection describes the ARIES research effort, with emphasis on the ARIES-I design, summarizing the major results, the key technical issues, and the central conclusions.

  14. CASTOR: Cathode/Anode Satellite Thruster for Orbital Repositioning

    Science.gov (United States)

    Mruphy, Gloria A.

    2010-01-01

    The purpose of CASTOR (Cathode/Anode Satellite Thruster for Orbital Repositioning) satellite is to demonstrate in Low Earth Orbit (LEO) a nanosatellite that uses a Divergent Cusped Field Thruster (DCFT) to perform orbital maneuvers representative of an orbital transfer vehicle. Powered by semi-deployable solar arrays generating 165W of power, CASTOR will achieve nearly 1 km/s of velocity increment over one year. As a technology demonstration mission, success of CASTOR in LEO will pave the way for a low cost, high delta-V orbital transfer capability for small military and civilian payloads in support of Air Force and NASA missions. The educational objective is to engage graduate and undergraduate students in critical roles in the design, development, test, carrier integration and on-orbit operations of CASTOR as a supplement to their curricular activities. This program is laying the foundation for a long-term satellite construction program at MIT. The satellite is being designed as a part of AFRL's University Nanosatellite Program, which provides the funding and a framework in which student satellite teams compete for a launch to orbit. To this end, the satellite must fit within an envelope of 50cmx50cmx60cm, have a mass of less than 50kg, and meet stringent structural and other requirements. In this framework, the CASTOR team successfully completed PDR in August 2009 and CDR in April 2010 and will compete at FCR (Flight Competition Review) in January 2011. The complexity of the project requires implementation of many systems engineering techniques which allow for development of CASTOR from conception through FCR and encompass the full design, fabrication, and testing process.

  15. Laser-fabricated castor oil-capped silver nanoparticles

    Science.gov (United States)

    Zamiri, Reza; Zakaria, Azmi; Abbastabar, Hossein; Darroudi, Majid; Husin, Mohd Shahril; Mahdi, Mohd Adzir

    2011-01-01

    Silver nanoparticles were fabricated by ablation of a pure silver plate immersed in castor oil. A Nd:YAG-pulsed Q-switch laser with 1064-nm wavelength and 10-Hz frequency was used to ablate the plate for 10 minutes. The sample was characterized by ultraviolet-visible, atomic absorption, Fourier transform-infrared spectroscopies, and transmission electron microscopy. The results of the fabricated sample showed that the nanoparticles in castor oil were about 5-nm in diameter, well dispersed, and showed stability for a long period of time. PMID:21698083

  16. Laser-fabricated castor oil-capped silver nanoparticles.

    Science.gov (United States)

    Zamiri, Reza; Zakaria, Azmi; Abbastabar, Hossein; Darroudi, Majid; Husin, Mohd Shahril; Mahdi, Mohd Adzir

    2011-01-01

    Silver nanoparticles were fabricated by ablation of a pure silver plate immersed in castor oil. A Nd:YAG-pulsed Q-switch laser with 1064-nm wavelength and 10-Hz frequency was used to ablate the plate for 10 minutes. The sample was characterized by ultraviolet-visible, atomic absorption, Fourier transform-infrared spectroscopies, and transmission electron microscopy. The results of the fabricated sample showed that the nanoparticles in castor oil were about 5-nm in diameter, well dispersed, and showed stability for a long period of time.

  17. Synthesis of carbon nanotubes using natural carbon precursor: Castor oil

    Science.gov (United States)

    Raziah, A. Z.; Junizah, A. R.; Saifuddin, N.

    2012-09-01

    Castor oil has long been an article of commerce due to its versatility as it is widely used as a starting material for many industrial chemical products because of its unique structure. In this study, carbon nanotubes has been synthesized by thermal decomposition of castor oil in nitrogen atmosphere at 300-400δC using custom-made microwave processing unit. The precursor material was catalyzed by iron clusters originating from the addition of ferrocene. The morphology and characterization of the CNTs were studied and discussed by transmission electron microscopy (TEM).

  18. Beaver (Castor canadensis) in heavily browsed environments

    Science.gov (United States)

    Baker, Bruce W.

    2003-01-01

    Beaver (Castor canadensis) populations have declined or failed to recover in heavily browsed environments. I suggest that intense browsing by livestock or ungulates can disrupt beaver-willow (Salix spp.) mutualisms that likely evolved under relatively low herbivory in a more predator-rich environment, and that this interaction may explain beaver and willow declines. Field experiments in Rocky Mountain National Park, Colorado, USA, found the interaction of beaver and elk (Cervus elaphus) herbivory suppressed compensatory growth in willow. Intense elk browsing of simulated beaver-cut willow produced plants which were small and hedged with a high percentage of dead stems, whereas protected plants were large and highly branched with a low percentage of dead stems. Evaluation of a winter food cache showed beaver had selected woody stems with a lower percentage of leaders browsed by elk. A lack of willow stems suitable as winter beaver food may cause beaver populations to decline, creating a negative feedback mechanism for beaver and willow. In contrast, if browsing by livestock or ungulates can be controlled, and beaver can disperse from a nearby source population, then beaver may build dams in marginal habitat which will benefit willow and cause a positive riparian response that restores proper function to degraded habitat. In a shrub-steppe riparian ecosystem of northwestern Colorado, USA, rest from overgrazing of livestock released herbaceous vegetation initiating restoration of a beaver-willow community. Thus, competition from livestock or ungulates can cause beaver and willow to decline and can prevent their restoration in heavily browsed riparian environments, but beaver and willow populations can recover under proper grazing management.

  19. Beta limits of a completely bootstrapped tokamak

    International Nuclear Information System (INIS)

    Weening, R.H.; Bondeson, A.

    1992-03-01

    A beta limit is given for a completely bootstrapped tokamak. The beta limit is sensitive to the achievable Troyon factor and depends directly upon the strength of the tokamak bootstrap effect. (author) 16 refs

  20. Bibliography of fusion product physics in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Hively, L. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sigmar, D. J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    1989-09-01

    Almost 700 citations have been compiled as the first step in reviewing the recent research on tokamak fusion product effects in tokamaks. The publications are listed alphabetically by the last name of the first author and by subject category.

  1. Fusion potential for spherical and compact tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Sandzelius, Mikael

    2003-02-01

    The tokamak is the most successful fusion experiment today. Despite this, the conventional tokamak has a long way to go before being realized into an economically viable power plant. In this master thesis work, two alternative tokamak configurations to the conventional tokamak has been studied, both of which could be realized to a lower cost. The fusion potential of the spherical and the compact tokamak have been examined with a comparison of the conventional tokamak in mind. The difficulties arising in the two configurations have been treated from a physical point of view concerning the fusion plasma and from a technological standpoint evolving around design, materials and engineering. Both advantages and drawbacks of either configuration have been treated relative to the conventional tokamak. The spherical tokamak shows promising plasma characteristics, notably a high {beta}-value but have troubles with high heat loads and marginal tritium breeding. The compact tokamak operates at a high plasma density and a high magnetic field enabling it to be built considerably smaller than any other tokamak. The most notable down-side being high heat loads and neutron transport problems. With the help of theoretical reactor studies, extrapolating from where we stand today, it is conceivable that the spherical tokamak is closer of being realized of the two. But, as this study shows, the compact tokamak power plant concept offers the most appealing prospect.

  2. Fusion potential for spherical and compact tokamaks

    International Nuclear Information System (INIS)

    Sandzelius, Mikael

    2003-02-01

    The tokamak is the most successful fusion experiment today. Despite this, the conventional tokamak has a long way to go before being realized into an economically viable power plant. In this master thesis work, two alternative tokamak configurations to the conventional tokamak has been studied, both of which could be realized to a lower cost. The fusion potential of the spherical and the compact tokamak have been examined with a comparison of the conventional tokamak in mind. The difficulties arising in the two configurations have been treated from a physical point of view concerning the fusion plasma and from a technological standpoint evolving around design, materials and engineering. Both advantages and drawbacks of either configuration have been treated relative to the conventional tokamak. The spherical tokamak shows promising plasma characteristics, notably a high β-value but have troubles with high heat loads and marginal tritium breeding. The compact tokamak operates at a high plasma density and a high magnetic field enabling it to be built considerably smaller than any other tokamak. The most notable down-side being high heat loads and neutron transport problems. With the help of theoretical reactor studies, extrapolating from where we stand today, it is conceivable that the spherical tokamak is closer of being realized of the two. But, as this study shows, the compact tokamak power plant concept offers the most appealing prospect

  3. Optimization of biodiesel production from castor oil by response ...

    African Journals Online (AJOL)

    This work investigated the possibility of using response surface methodology based on a four factor five level central composite design to optimize biodiesel production from castor oil. The reaction variables were oil: ethanol ratio, lipozyme concentration, time and temperature. The properties of the biodiesel produced were ...

  4. Interpenetrating polymer networks based on polyol modified castor ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Interpenetrating polymer networks (IPNs) of glycerol modified castor oil polyurethane (GC–PU) and poly[2-hydroxyethylmethacrylate] (PHEMA) were synthesized using benzoyl peroxide as initiator and. N,N-methylene bis acrylamide as crosslinker. GC–PU/PHEMA interpenetrating polymer networks were obtained ...

  5. Seed Borne fungi Castor Oil ( Ricinus cummunis ): Effect of Their ...

    African Journals Online (AJOL)

    An investigation of fungi associated with castor oil seeds collected from four different locations in Nigeria showed Aspergillus niger, A. flavus, Fusarium moniliforme and Penicillium spp. to be the most abundant. Metabolites from these fungi significantly (p=0.05) depressed seed germination and seedling establishment.

  6. Synthesis and characterization of castor oil based polyurethane ...

    Indian Academy of Sciences (India)

    Unknown

    Castor oil; MDI; interpenetrating; mechanical; crystal size; strain. 1. Introduction. Interpenetrating polymer networks (IPNs) constitute a group of polymer composite materials possessing unique properties which are related to their method of synthe- sis (Sperling 1981). IPNs typically consist of a flexible elastomer and one or ...

  7. Inheritance of Plant Height in two Ethiopian Castor Varieties

    African Journals Online (AJOL)

    The green revolution in Asia was led by the semi dwarf varieties of wheat and rice during the 1960s. Nowadays ... Castor (Racinnus communis L.) is an industrial non edible oil seed that originated in East. Africa probably Ethiopia ... At the fourth generation single plants from each inbred line were reciprocally crossed to ...

  8. Evaluation of castor oil samples for potential toxin contamination

    Science.gov (United States)

    Castor oil and its derivatives are widely used as a chemical feedstock for production of lubricants and greases, and for engineering plastics, plasticizers and surfactants. They also have wide application in consumer goods such as lipstick, deodorants and medicinal products. Due to concerns about th...

  9. response of clarias gariepinus to dietary castor seeds processed

    African Journals Online (AJOL)

    Admin

    cake is obtained as a residue of oil extraction from castor seeds. The cake has high protein content of 39%, crude fibre 18%, 7.5% ash, 3% soluble carbohydrate and. 40% ether extract (Devendra, 1988). In spite of the high nutrient content of the cake, its use in feeding animals is limited due to the presence of some toxicants ...

  10. Comparative Analysis of Flame Characteristics of Castor Oil and ...

    African Journals Online (AJOL)

    The flame characteristics of castor oil based foam and that of polyether foam impregnated with inorganic flame retardants (FR) were investigated. The polyether foams were impregnated with measured concentration of Antimony trioxide and Sodium bromide, Ammonium dihydrogen orthophosphate, Diammonium hydrogen ...

  11. Early Stage Design of a Bio refinery from Castor Oil

    DEFF Research Database (Denmark)

    de Faria, Daniela; Quaglia, Alberto; Pessoa, Fernando

    2014-01-01

    and network scenarios. The tool integrates d ata collection, modelling and superstructure optimization to determine the optimal network for a biorefinery. The application of the synthesis - analysis method and its corresponding computer aided tool is highlighte d for a case study where castor oil...

  12. Growth response of Ricinus communis L (castor oil) in spent ...

    African Journals Online (AJOL)

    The growth response of castor oil plant, Ricinus communis, in spent lubricating oil (SLO) was investigated using 1-6% w/w SLO and a control. The result showed that highest percent germination of approximately 92, was obtained in control and the least in 5% w/w. The early germination obtained in this study was significant ...

  13. Interpenetrating polymer networks based on polyol modified castor ...

    Indian Academy of Sciences (India)

    Interpenetrating polymer networks (IPNs) of glycerol modified castor oil polyurethane (GC–PU) and poly[2-hydroxyethylmethacrylate] (PHEMA) were synthesized using benzoyl peroxide as initiator and N,N-methylene bis acrylamide as crosslinker. GC–PU/PHEMA interpenetrating polymer networks were obtained by ...

  14. Composition of acylglycerols in castor oil and their biosynthetic pathway

    Science.gov (United States)

    Castor oil has many industrial uses, such as the manufacture of aviation lubricant, plastics, paints, coatings, and cosmetics, because of its high content of ricinoleate (hydroxy fatty acid). We have identified many molecular species of acylglycerols using electrospray ionization mass spectrometry o...

  15. Comparative Analysis of Flame Characteristics of Castor Oil and ...

    African Journals Online (AJOL)

    ABSTRACT: The flame characteristics of castor oil based foam and that of polyether foam impregnated with inorganic flame retardants (FR) were investigated. The polyether foams were impregnated with measured concentration of Antimony trioxide and Sodium bromide, Ammonium dihydrogen orthophosphate ...

  16. Develop a New Lesquerella fendleri Crop for Castor Oil Production

    Science.gov (United States)

    Seed oil of Lesquerella fendleri contains a valuable hydroxy fatty acid (HFA), lesquerolic acid (20:1OH). The conventional source of HFA is ricinoleic acid (18:1OH) from castor seeds. Ricinoleic acid and its derivatives are used as raw materials for numerous industrial products, such as lubricants, ...

  17. EFFECT OF CASTOR BEAN (Ricinus communis L.) AQUEOUS ...

    African Journals Online (AJOL)

    User

    EFFECT OF CASTOR BEAN (Ricinus communis L.) AQUEOUS. EXTRACTS ON THE PERFORMANCE OF ROOT-KNOT. NEMATODES (Meloidogyne spp.) ON TOMATO. (Solanum lycopersicum L.) J. Adomako1 and C. K. Kwoseh2. 1. Plant Health Division, CSIR-Crops Research Institute, Fumesua, Kumasi. 2. Department ...

  18. Diversity of castor ( Ricinus communis L.) in Ethiopia | Alemaw ...

    African Journals Online (AJOL)

    An experiment was carried out to assess the diversity of castor germplasm in Ethiopia. A total of 102 accessions, one elite genotype and two standard varieties were characterized at Melkassa and Arsi Negelle, in the Central Rift Valley of Ethiopia using 12 traits for one during 2013 main season. Analysis of variance ...

  19. GNS Castor V/21 Headspace Gas Sampling 2014

    Energy Technology Data Exchange (ETDEWEB)

    Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-01

    Prior to performing an internal visual inspection, samples of the headspace gas of the GNS Castor V/21 cask were taken on June 12, 2014. These samples were taken in support of the CREIPI/Japanese nuclear industry effort to validate fuel integrity without visual inspection by measuring the 85Kr content of the cask headspace

  20. Advanced tokamak burning plasma experiment

    International Nuclear Information System (INIS)

    Porkolab, M.; Bonoli, P.T.; Ramos, J.; Schultz, J.; Nevins, W.N.

    2001-01-01

    A new reduced size ITER-RC superconducting tokamak concept is proposed with the goals of studying burn physics either in an inductively driven standard tokamak (ST) mode of operation, or in a quasi-steady state advanced tokamak (AT) mode sustained by non-inductive means. This is achieved by reducing the radiation shield thickness protecting the superconducting magnet by 0.34 m relative to ITER and limiting the burn mode of operation to pulse lengths as allowed by the TF coil warming up to the current sharing temperature. High gain (Q≅10) burn physics studies in a reversed shear equilibrium, sustained by RF and NB current drive techniques, may be obtained. (author)

  1. Plasma boundary phenomena in tokamaks

    International Nuclear Information System (INIS)

    Stangeby, P.C.

    1989-06-01

    The focus of this review is on processes occurring at the edge, and on the connection between boundary plasma - the scrape-off layer (SOL) and the radiating layer - and central plasma processes. Techniques used for edge diagnosis are reviewed and basic experimental information (n e and T e ) is summarized. Simple models of the SOL are summarized, and the most important effects of the boundary plasma - the influence on the fuel particles, impurities, and energy - on tokamak operation dealt with. Methods of manipulating and controlling edge conditions in tokamaks and the experimental data base for the edge during auxiliary heating of tokamaks are reviewed. Fluctuations and asymmetries at the edge are also covered. (9 tabs., 134 figs., 879 refs.)

  2. Summary discussion: An integrated advanced tokamak reactor

    International Nuclear Information System (INIS)

    Sauthoff, N.R.

    1994-01-01

    The tokamak concept improvement workshop addressed a wide range of issues involved in the development of a more attractive tokamak. The agenda for the workshop progressed from a general discussion of the long-range energy context (with the objective being the identification of a set of criteria and ''figures of merit'' for measuring the attractiveness of a tokamak concept) to particular opportunities for the improvement of the tokamak concept. The discussions concluded with a compilation of research program elements leading to an improved tokamak concept

  3. Identification of minor acylglycerols less polar than triricinolein in castor oil by mass spectrometry and the proposed biosynthetic pathway of castor oil

    Science.gov (United States)

    Ricinoleate (OH18:1), a monohydroxy fatty acid, has many industrial uses such as the manufacture of biodegradable plastics, nylon, plasticizers, lubricants, cosmetics and paints. Castor oil is the only commericial source of ricinoleate which occurs as triacylglycerols. Triacylglycerols in castor oil...

  4. STARFIRE: a commercial tokamak reactor

    International Nuclear Information System (INIS)

    1979-12-01

    The purpose of this document is to provide an interim status report on the STARFIRE project for the period of May to September 1979. The basic objective of the STARFIRE project is to develop a design concept for a commercial tokamak fusion electric power plant based on the deuterium/tritium/lithium fuel cycle. The key technical objective is to develop the best embodiment of the tokamak as a power reactor consistent with credible engineering solutions to design problems. Another key goal of the project is to give careful attention to the safety and environmental features of a commercial fusion reactor

  5. Tokamak SST-1: an over-view

    International Nuclear Information System (INIS)

    Saxena, Y.C.

    2002-01-01

    Steady State Tokamak SST-1 is in advanced stage of fabrication at the Institute for Plasma Research. The objectives of SST-1 include studying the physics of the plasma processes in tokamak under steady state conditions and learning technologies related to the steady state operation of the tokamak with superconducting magnets. These studies are expected to contribute to the tokamak physics database for very long pulse operations. The SST-1 tokamak is a large aspect ratio tokamak, configured to run double null diverted plasmas for 1000 s with significant elongation (K) and triangularity (δ). The choice of the parameters is dictated by the physics and technology goals viz. (a) to control and study strongly shaped single and double null divertor plasma, (b) explore advanced tokamak plasma regimes, (c) steady state particle and heat removal from the device, (d) design and operation of large volume superconducting magnets, (e) non-inductive steady state current drive, (f) methods of plasma heating and (g) material technologies

  6. The tokamak hybrid reactor

    International Nuclear Information System (INIS)

    Kelly, J.L.; Rose, R.P.

    1981-01-01

    At a time when the potential benefits of various energy options are being seriously evaluated in many countries through-out the world, it is both timely and important to evaluate the practical application of fusion reactors for their economical production of nuclear fissile fuels from fertile fuels. The fusion hybrid reactor represents a concept that could assure the availability of adequate fuel supplies for a proven nuclear technology and have the potential of being an electrical energy source as opposed to an energy consumer as are the present fuel enrichment processes. Westinghouse Fusion Power Systems Department, under Contract No. EG-77-C-02-4544 with the Department of Energy, Office of Fusion Energy, has developed a preliminary conceptual design for an early twenty-first century fusion hybrid reactor called the commercial Tokamak Hybrid Reactor (CTHR). This design was developed as a first generation commercial plant producing fissile fuel to support a significant number of client Light Water Reactor (LWR) Plants. To the depth this study has been performed, no insurmountable technical problems have been identified. The study has provided a basis for reasonable cost estimates of the hybrid plants as well as the hybrid/LWR system busbar electricity costs. This energy system can be optimized to have a net cost of busbar electricity that is equivalent to the conventional LWR plant, yet is not dependent on uranium ore prices or standard enrichment costs, since the fusion hybrid can be fueled by numerous fertile fuel resources. A nearer-term concept is also defined using a beam driven fusion driver in lieu of the longer term ignited operating mode. (orig.)

  7. Tokamak Plasmas : Mirnov coil data analysis for tokamak ADITYA

    Indian Academy of Sciences (India)

    The spatial and temporal structures of magnetic signal in the tokamak ADITYA is analysed using recently developed singular value decomposition (SVD) technique. The analysis technique is first tested with simulated data and then applied to the ADITYA Mirnov coil data to determine the structure of current peturbation as ...

  8. Tokamak Plasmas: Mirnov coil data analysis for tokamak ADITYA

    Indian Academy of Sciences (India)

    The spatial and temporal structures of magnetic signal in the tokamak ADITYA is analysed using recently developed singular value decomposition (SVD) technique. The analysis technique is first tested with simulated data and then applied to the ADITYA Mirnov coil data to determine the structure of current peturbation as ...

  9. Castor and jatropha oils: production strategies – A review

    Directory of Open Access Journals (Sweden)

    Lago Regina C.A.

    2009-07-01

    Full Text Available The Brazilian bioenergy matrix is based on four platforms: ethanol, energy forests, residues and co-products and biodiesel. The food-energy dichotomy in the use of edible oils is one factor which has stimulated the search for non-edible oleaginous energy crops, such as many native palms. By the year 2000 Brazil had an annual deficit of 80 thousand tons of castor oil, making necessary to import oil from China and India. After a strong debate the National Program on Biodiesel Production (NPBP was launched by December 2004. After an initial excessive enthusiasm, small producers being focused in the program, a more mature and realistic planning is undertaken. Production in semi arid lands is being stimulated, mainly castor (Ricinus communis and Jatropha (Jatropha curcas. Apart from belonging to the same botanical family (Euphorbiaceae, both plants are well resistant to poor soils. Castor plant is well adapted to practically the whole country, except for some extreme areas (too low water availability or too much rain. Castor keeps being an alternative for the semi arid region but much more technology is requested to make it largely exploited. Following the petroleum crisis of 1980’s an ambitious research program on Jatropha curcas was initiated, later on discontinued and presently retaken by Embrapa and some Universities. Progress is slower than in the case of Ricinus communis. The first agronomical observations confirmed low productivity, problems with pests and diseases, high harvesting costs etc. Some strategic factors should be considered for the production of castor and Jatropha oils: 1. Production of raw materials; 2. Production of oils; 3. Detoxification and value aggregation to the extraction cakes and residues. Regarding raw material production, it is necessary a strong, long term research program on genetic breeding (short cycle varieties, with high productivity and allowing a sole harvesting, soil fertility, pest control, domestication

  10. Effect of castor cake and elephant grass composting on edaphic fauna

    OpenAIRE

    Scoriza,Rafael Nogueira; Bianchi,Miriam de Oliveira; Correia,Maria Elizabeth Fernandes; Leal,Marco Antonio de Almeida

    2016-01-01

    ABSTRACT: Elephant grass and castor cake when combined can make a promising organic fertilizer. However, castor cake contains potentially toxic chemicals, such as ricin and ricinine. To test potential effects of these chemicals, compost piles of elephant grass ( Pennisetum purpureum Schum.) with castor cake were prepared with different C:N ratios (T1 = 40, T2 = 30, T3 = 20; T4 = 30 [control, elephant grass + crotalaria]) to evaluate colonization by edaphic fauna and any suppressive effects of...

  11. Preparation and research on properties of castor oil as a diesel fuel additive

    OpenAIRE

    Nurbakhit Imankulov

    2012-01-01

    The research shows an opportunity of preparing biodiesel fuel on the basis of local diesel fuel and the bioadditive - castor oil. Limiting optimum concentration of introduction of the bioadditive equal was established as 5% mass ratio. The castor oil released from seeds of Palma Christi grown on experimental field. All physical and chemical characteristics of the oil including IR-spectra were determined. Operating conditions of castor oil introduction (temperature, solubility, concentra-tion,...

  12. Tokamak experimental power reactor studies

    International Nuclear Information System (INIS)

    1975-06-01

    The principal results of a scoping and project definition study for the Tokamak Experimental Power Reactor are presented. Objectives are discussed; a preliminary conceptual design is described; detailed parametric, survey and sensitivity studies are presented; and research and development requirements are outlined. (U.S.)

  13. ECRH Studies on Tokamak Plasmas.

    Science.gov (United States)

    1980-10-10

    r.I*cru.Dtrtibution uUnliited 300 Unicorn Pork Drive Woburn, Massachusetts 04801 ECRH STUDIES ON TOKAMAK PLASMAS JAYCOR Project No. 6183 Final Report...wavelength polariza- tion field produced by the curvature and field gradient drifts [15]. The growth rate is y = Vs[k/R 2 = [T(eV)/X(cm)J 2 3.3 x 105 sec

  14. TECHNOLOGIES TO OPTIMIZE ADVANCED TOKAMAK

    Energy Technology Data Exchange (ETDEWEB)

    SIMONEN, TC

    2004-01-01

    OAK-B135 Commercial fusion power systems must operate near the limits of the engineering systems and plasma parameters. Achieving these objectives will require real time feedback control of the plasma. This paper describes plasma control systems being used in the national DIII-D advanced tokamak research program.

  15. Prospects for Tokamak Fusion Reactors

    International Nuclear Information System (INIS)

    Sheffield, J.; Galambos, J.

    1995-01-01

    This paper first reviews briefly the status and plans for research in magnetic fusion energy and discusses the prospects for the tokamak magnetic configuration to be the basis for a fusion power plant. Good progress has been made in achieving fusion reactor-level, deuterium-tritium (D-T) plasmas with the production of significant fusion power in the Joint European Torus (up to 2 MW) and the Tokamak Fusion Test Reactor (up to 10 MW) tokamaks. Advances on the technologies of heating, fueling, diagnostics, and materials supported these achievements. The successes have led to the initiation of the design phases of two tokamaks, the International Thermonuclear Experimental Reactor (ITER) and the US Toroidal Physics Experiment (TPX). ITER will demonstrate the controlled ignition and extended bum of D-T plasmas with steady state as an ultimate goal. ITER will further demonstrate technologies essential to a power plant in an integrated system and perform integrated testing of the high heat flux and nuclear components required to use fusion energy for practical purposes. TPX will complement ITER by testing advanced modes of steady-state plasma operation that, coupled with the developments in ITER, will lead to an optimized demonstration power plant

  16. Tokamak impurity-control techniques

    International Nuclear Information System (INIS)

    Schmidt, J.A.

    1980-01-01

    A brief review is given of the impurity-control functions in tokamaks, their relative merits and disadvantages and some prominent edge-interaction-control techniques, and there is a discussion of a new proposal, the particle scraper, and its potential advantages. (author)

  17. Joint research using small tokamaks

    Czech Academy of Sciences Publication Activity Database

    Gryaznevich, M.P.; Del Bosco, E.; Malaquias, A.; Mank, G.; Van Oost, G.; He, Yexi; Hegazy, H.; Hirose, A.; Hron, Martin; Kuteev, B.; Ludwig, G.O.; Nascimento, I.C.; Silva, C.; Vorobyev, G.M.

    2005-01-01

    Roč. 45, č. 10 (2005), S245-S254 ISSN 0029-5515. [Fusion Energy Conference contributions. Vilamoura, 1.11.2004-6.11.2004] Institutional research plan: CEZ:AV0Z20430508 Keywords : small tokamaks * thermonuclear fusion Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.418, year: 2005

  18. An enhanced tokamak startup model

    Science.gov (United States)

    Goswami, Rajiv; Artaud, Jean-François

    2017-01-01

    The startup of tokamaks has been examined in the past in varying degree of detail. This phase typically involves the burnthrough of impurities and the subsequent rampup of plasma current. A zero-dimensional (0D) model is most widely used where the time evolution of volume averaged quantities determines the detailed balance between the input and loss of particle and power. But, being a 0D setup, these studies do not take into consideration the co-evolution of plasma size and shape, and instead assume an unchanging minor and major radius. However, it is known that the plasma position and its minor radius can change appreciably as the plasma evolves in time to fill in the entire available volume. In this paper, an enhanced model for the tokamak startup is introduced, which for the first time takes into account the evolution of plasma geometry during this brief but highly dynamic period by including realistic one-dimensional (1D) effects within the broad 0D framework. In addition the effect of runaway electrons (REs) has also been incorporated. The paper demonstrates that the inclusion of plasma cross section evolution in conjunction with REs plays an important role in the formation and development of tokamak startup. The model is benchmarked against experimental results from ADITYA tokamak.

  19. Computer predictions for future Tokamaks

    International Nuclear Information System (INIS)

    Duechs, D.F.

    1978-01-01

    Proceeding from a reasonable agreement with existing experimental results, this lecture presents radial particle and energy transport computations which extrapolate to large (up to reactor dimensions) future Tokamaks. Special consideration is given to the behavior of alpha-particles, the influence of high-z impurities, and the thermal stability of the plasma

  20. Biodiesel production from castor oil in Brazil: A difficult reality

    International Nuclear Information System (INIS)

    Silva Cesar, Aldara da; Otavio Batalha, Mario

    2010-01-01

    The Brazilian National Program for Production and Use of Biodiesel (PNPB in Portuguese) has created a huge demand for biodiesel in Brazil. The PNPB is strongly based on social development through the inclusion of family farmers in projects integrated with biodiesel power plants. Among the various oilseeds, castor bean (Ricinus communis L.) was identified as the ideal one to promote social development in the semi-arid region. However, although promising, the mechanisms of the federal program are still insufficient to promote the effective participation of family farmers. This research shows that companies are facing huge problems in implementing contracts with family farmers. It describes and analyzes the functioning dynamics of this agro-production chain. This paper addresses the identification and the discussion of these obstacles, in order to increase the competitiveness of the biodiesel agribusiness chain, based on castor oil social projects in Brazil.

  1. Biodiesel production from castor oil in Brazil. A difficult reality

    Energy Technology Data Exchange (ETDEWEB)

    Silva Cesar, Aldara da; Otavio Batalha, Mario [Federal University of Sao Carlos, Gepai - Grupo de Estudos e Pesquisas Agroindustriais, Departamento de Engenharia de Producao - UFSCar, Rodovia Washington Luis, km 235 - CEP 13565-905 - Sao Carlos (Brazil)

    2010-08-15

    The Brazilian National Program for Production and Use of Biodiesel (PNPB in Portuguese) has created a huge demand for biodiesel in Brazil. The PNPB is strongly based on social development through the inclusion of family farmers in projects integrated with biodiesel power plants. Among the various oilseeds, castor bean (Ricinus communis L.) was identified as the ideal one to promote social development in the semi-arid region. However, although promising, the mechanisms of the federal program are still insufficient to promote the effective participation of family farmers. This research shows that companies are facing huge problems in implementing contracts with family farmers. It describes and analyzes the functioning dynamics of this agro-production chain. This paper addresses the identification and the discussion of these obstacles, in order to increase the competitiveness of the biodiesel agribusiness chain, based on castor oil social projects in Brazil. (author)

  2. Biodiesel production from castor oil in Brazil: A difficult reality

    Energy Technology Data Exchange (ETDEWEB)

    Silva Cesar, Aldara da, E-mail: aldara@dep.ufscar.b [Federal University of Sao Carlos, Gepai - Grupo de Estudos e Pesquisas Agroindustriais, Departamento de Engenharia de Producao - UFSCar, Rodovia Washington Luis, km 235 - CEP 13565-905 - Sao Carlos - SP (Brazil); Otavio Batalha, Mario [Federal University of Sao Carlos, Gepai - Grupo de Estudos e Pesquisas Agroindustriais, Departamento de Engenharia de Producao - UFSCar, Rodovia Washington Luis, km 235 - CEP 13565-905 - Sao Carlos - SP (Brazil)

    2010-08-15

    The Brazilian National Program for Production and Use of Biodiesel (PNPB in Portuguese) has created a huge demand for biodiesel in Brazil. The PNPB is strongly based on social development through the inclusion of family farmers in projects integrated with biodiesel power plants. Among the various oilseeds, castor bean (Ricinus communis L.) was identified as the ideal one to promote social development in the semi-arid region. However, although promising, the mechanisms of the federal program are still insufficient to promote the effective participation of family farmers. This research shows that companies are facing huge problems in implementing contracts with family farmers. It describes and analyzes the functioning dynamics of this agro-production chain. This paper addresses the identification and the discussion of these obstacles, in order to increase the competitiveness of the biodiesel agribusiness chain, based on castor oil social projects in Brazil.

  3. RESTORATIVE ASPECT OF CASTOR PLANT ON MAMMALIAN PHYSIOLOGY: A REVIEW

    Directory of Open Access Journals (Sweden)

    Attila Kádasi

    2011-10-01

    Full Text Available The castor plant (Ricinus communis L. is a robust perennial shrub of Euphorbiaceae family and different parts of the plant are widely used by various communities and forest dwellers in many regions of the world for treating a variety of ailments. About 80% of world population is still dependent on traditional herbal medicines. The plant is documented to possess beneficial effects as anti-oxidant, antifertility, anti inflammatory, antimicrobial, central nervous system stimulant, anti diabetic, insecticidal and larvicidal and many other medicinal properties. The extracts or the isolated compounds of this plant have been found to have potent activity against various ailments. The aim of this paper is to scrutinize the available literature related to the restorative activity of the castor plant as a herbal medicine on mammalian physiology and to accumulate those scientifically valid data in a nut shell in the form of a mini review.

  4. Production of quartz plates for CMS-CASTOR Experiment

    CERN Document Server

    Adiguzel, Aytul; Ayhan, Aydin; Bakirci, Mustafa Numan; Basegmez, Suzan; Beaumont, Willem; Borras, Kerstin; Campbell, Alan; De Paula Carvalho, W; Çerçi, Salim; De Jesus Damiao, Dilson; Dogangün, O; Dumanoglu, Isa; d'Enterria, David; Erchov, Y; Eskut, Eda; Figueiredo, D; Girgis, Semiray; Göttlicher, P; Gouskos, Loukas; Gurpinar, Emine; Hos, Ilknur; Katkov, Igor; Katsas, Panagiotis; Khein, Lev; Knutsson, Albert; Kuznetsov, Andrey; Lebeau, Michel; Van Mechelen, Pierre; Muhl, Carsten; Musienko, Yuri; Ochesanu, Silvia; Onengüt, G; Onengut, G Jr; Ozdemir, Kadri; Panagiotou, Apostolos; Polatoz, A; Ripert, Marion; Shileev, K; Sogut, Kenan; Tiflov, B TaliV; Kayis-Topaksu, A; Uzun, Dilber

    2008-01-01

    Light transmission rate performance of $102$ irradiated quartz samples was measured to select the best quartz plates for CMS-CASTOR calorimeter. All the produced quartz plates were originally used in a previous CERN experiment, DELPHI. Three different doses of $^{60}$Co source were used with the collaboration of PSI (Paul Scherrer Institute, Villigen PSI, Switzerland.) to study the transmission rate performance of the quartz samples after irradiation for different incident light, ranging from $250$ to $700$ nm in $5$ nm increasing steps. All samples show different decrease in the rate with wavelength for different doses. Three different steps were followed before irradiation to find out the best way of cleaning the original DELPHI Cu/Cr tracks on the samples. Results of these measurements presented here correspond to the quartz plates that will be used in one hadronic sector of CASTOR calorimeter until end of 2008. For the full calorimeter new quartz plates will be installed. We also present the light transmi...

  5. Fallot's tetralogy in a European beaver (Castor fiber).

    Science.gov (United States)

    Wenger, Sandra; Gull, Jessica; Glaus, Tony; Blumer, Serafin; Wimmershoff, Julia; Kranjc, Asja; Steinmetz, Hanspeter; Hatt, Jean-Michel

    2010-06-01

    A 20-mo-old, female, 9-kg European beaver (Castor fiber) presented with apathy, reduced appetite of 3-day duration and a grade 5/6 systolic heart murmur. Thoracic radiographs revealed a diffuse broncho-interstitial pattern suspicious for bronchopneumonia. The echocardiographic findings of a hypertrophied right ventricle, ventricular septal defect with overriding aorta, and infundibular pulmonic stenosis were consistent with Fallot's tetralogy. Even though the bronchopneumonia rather than the congenital cardiac defect was considered of primary importance for the presenting clinical signs, the latter was relevant for the decision not to continue any medical treatment. Both disease processes were confirmed on necropsy. Fallot's tetralogy, European beaver, Castor fiber, heart murmur, ultrasound.

  6. Extraction, Characterization and Modification of Castor Seed Oil

    Directory of Open Access Journals (Sweden)

    A. D. MOHAMMED

    2006-01-01

    Full Text Available This paper carried out experimental study, through extraction and characterization of both crude and refined castor oil. Normal hexane was used as solvent for the extraction process. The oil produced was refined through degumming, neutralization and bleaching process using local adsorbent (activated clay. The characterization analysis revealed that tested parameters, which include specific gravity, refractive index, acid value, saponification value and iodine value for both crude and refined castor oil produced, were within the ASTM standard specifications. In fact the iodine value obtained (84.8 for the refined oil indicates that the oil could certainly be used as lubricant, hydraulic break fluid and protecting coatings. The oil was modified via sulphation method to produce Turkey – red oil that was tested on wooden material, paper and cloth. The test revealed that the Turkey – red oil produced is suitable to be used as a good dying agent and polish.

  7. pre-germination treatments in castor seeds, cultivar IAC 226

    International Nuclear Information System (INIS)

    Costa Nobre, Danubia Aparecida; Gomes Damascena, Joyce; Marcia, Andreia; Santos de Souza, David; Pereira dos Santos, Marlucia; Rodrigues Pereira, Adriana; Goncalves Pereira, Cassio

    2013-01-01

    The present study aimed to evaluate the efficiency of different pre-germination treatments in castor beans, IAC 226. The experimental design was completely randomized in a factorial 4 x 4 (four temperatures and four immersion times), with four replications. Pre-germination treatments were: immersion in water at room temperature (25 Celsius degrade) and immersion in hot water at temperatures of 60, 70 and 80 Celsius degrade for 2, 4, 6 and 8 minutes. Water content of the seeds was determined before treatments. Before and after each treatment, seeds were subjected to germination test; 20-30 Celsius degrade alternating temperature, determining the percentages of normal and abnormal seedlings, dormant and dead seeds. Independent of time, immersion in 70 Celsius degrade, water was the most efficient treatment for accelerating germination of castor bean cultivar IAC 226.

  8. "Castor Oil" - The Culprit of Acute Hair Felting.

    Science.gov (United States)

    Maduri, V Ramya; Vedachalam, Ahalya; Kiruthika, S

    2017-01-01

    Acute hair felting is a rare disorder of scalp hair. In this condition, the hair becomes twisted, entangled as a hard stony mass resembling a bird's nest. Sudden hair matting has been reported earlier in the literature after vigorous use of chemical and herbal shampoos. Plica polonica is a patchy area of hair matting occurring in due course of time in neglected hair or underlying psychiatric illness. This case is interesting as the whole scalp hair matted immediately after using coconut oil and castor oil following washing. Growing long hair and taking oil bath are cultural and religious customs in South India. The high viscosity of castor oil and long hair had contributed to sudden felting of hair. This disorder of hair is irreversible and the hair should be cut off. Acute nature of this disorder will result in a serious psychological impact on the patient and the family.

  9. Advanced statistics for tokamak transport colinearity and tokamak to tokamak variation

    International Nuclear Information System (INIS)

    Riedel, K.S.

    1989-01-01

    This paper is an expository introduction to advanced statistics and scaling laws and their application to tokamak devices. Topics of discussion are as follows: implicit assumptions in the standard analysis; advanced regression techniques; specialized tools in statistics and their applications in fusion physics; and improved datasets for transport studies

  10. Variations in seed traits of castor ( Ricinus communis ) accessions ...

    African Journals Online (AJOL)

    The physicochemical analysis showed that castor seed and oil had saponification value of 182.9 mg/g, moisture content of 4.4%, acid value of 3.085 mg/g, viscosity of 110.41 cP, pH of 6.11, iodine value of 8.46 mg/g, specific gravity of 0.962 and refractive index of 1.477˚C. The proximate analysis showed that moisture ...

  11. The experiences from interim spent fuel storage operation with CASTOR 440/84 CASKS in NPP Dukovany

    International Nuclear Information System (INIS)

    Kuba, S.

    1999-01-01

    In this lecture are presented: principles of the CASTOR 440/84 design; design development works; commissioning of interim spent fuel storage facility; international transports of spent fuel utilising CASTOR 440/84 casks

  12. Effect of copper on castor bean (Ricinus communis L.) growth

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Lucia Helena Garofalo; Cunha, Tassio Cavalcanti da Silva; Lima, Vinicius Mota; Cabral, Paulo Cesar Pinto; Barros Junior, Genival; Lacerda, Rogerio Dantas de [Universidade Federal de Campina Grande (UAEAg/UFCG), PB (Brazil). Unidade Academica de Engenharia Agricola

    2008-07-01

    Castor beans crop (Ricinus communis L.) is raising attention as an alternative crop for oil and biodiesel production. Despite the mineral fertilization is an important factor for increasing castor yield, few research has been made on this issue, mainly on the use de copper. In order to evaluate the effects of copper on growth of this plant an experiment was carried out in a greenhouse, in Campina Grande, Paraiba State, Brazil, from July to December 2007. The substrate for the pot plants was a 6 mm-sieved surface soil (Neossolo Quartzarenico). The experimental design was a completely randomized with three replications. The treatments were composed of five levels of Cu (0; 1; 2; 3 and 4 mg dm{sup -3}), which were applied at the time of planting. One plant of castor bean, cultivar BRS 188 - Paraguacu, was grown per pot after thinning and was irrigated whenever necessary. Data on plant height, number and length of leaves and stem diameter were measured at 21, 34, 77 and 103 days after planting. Copper levels used, in general, did not affect the plant height, stem diameter and leaf area, however they influenced the leaves and shoot biomass dry mass and the quadratic trend was the best to show the behavior of these. (author)

  13. Trial of an experimental castor oil solution for cleaning dentures.

    Science.gov (United States)

    Andrade, Ingrid Machado de; Andrade, Kelly Machado de; Pisani, Marina Xavier; Silva-Lovato, Cláudia Helena; de Souza, Raphael Freitas; Paranhos, Helena de Freitas Oliveira

    2014-01-01

    Denture hygiene is essential because denture biofilm is involved in oral infections and systemic diseases. Although there are chemical agents available on the market, none of them have ideal properties and research on such products is still necessary. The aim of this study was to evaluate the efficacy of a castor bean (Ricinus communis)-based solution for removing denture biofilm, compared to two traditional products (sodium hypochlorite and alkaline peroxide). Fifty maxillary complete denture wearers were instructed to brush their dentures after meals and to immerse their dentures once a day in the following solutions: Saline (20 min; control), Polident alkaline peroxide (3 min), NaOCl (20 min) and 2% castor oil solution (20 min). Participants used each solution for a period of 7 consecutive days, according to a random sequence. After each period, the internal surfaces of maxillary complete dentures were stained with a disclosing solution (1% neutral red), photographed and the disclosed biofilm was quantified with the aid of specific software. The influence of treatments on results was verified by the Friedman test (α=0.05). Tested solutions presented significant difference (Fr=51.67; pcastor oil presented intermediate results (median: 1.0% and 1.5%, respectively). It can be concluded that the castor oil solution tested in this study was comparable to alkaline peroxide in terms of efficiency in denture biofilm removal.

  14. Low-modulus PMMA bone cement modified with castor oil.

    Science.gov (United States)

    López, Alejandro; Hoess, Andreas; Thersleff, Thomas; Ott, Marjam; Engqvist, Håkan; Persson, Cecilia

    2011-01-01

    Some of the current clinical and biomechanical data suggest that vertebroplasty causes the development of adjacent vertebral fractures shortly after augmentation. These findings have been attributed to high injection volumes as well as high Young's moduli of PMMA bone cements compared to that of the osteoporotic cancellous bone. The aim of this study was to evaluate the use of castor oil as a plasticizer for PMMA bone cements. The Young's modulus, yield strength, maximum polymerization temperature, doughing time, setting time and the complex viscosity curves during curing, were determined. The cytotoxicity of the materials extracts was assessed on cells of an osteoblast-like cell line. The addition of up to 12 wt% castor oil decreased yield strength from 88 to 15 MPa, Young's modulus from 1500 to 446 MPa and maximum polymerization temperature from 41.3 to 25.6°C, without affecting the setting time. However, castor oil seemed to interfere with the polymerization reaction, giving a negative effect on cell viability in a worst-case scenario.

  15. Measurement of quadratic electrogyration effect in castor oil

    Science.gov (United States)

    Izdebski, Marek; Ledzion, Rafał; Górski, Piotr

    2015-07-01

    This work presents a detailed analysis of electrogyration measurement in liquids with the usage of an optical polarimetric technique. Theoretical analysis of the optical response to an applied electric field is illustrated by experimental data for castor oil which exhibits natural optical activity, quadratic electro-optic effect and quadratic electrogyration effect. Moreover, the experimental data show that interaction of the oil with a pair of flat electrodes induces a significant dichroism and natural linear birefringence. The combination of these effects occurring at the same time complicates the procedure of measurements. It has been found that a single measurement is insufficient to separate the contribution of the electrogyration effect, but it is possible on the basis of several measurements performed with various orientations of the polarizer and the analyser. The obtained average values of the quadratic electrogyration coefficient β13 in castor oil at room temperature are from - 0.92 ×10-22 to - 1.44 ×10-22m2V-2 depending on the origin of the oil. Although this study is focused on measurements in castor oil, the presented analysis is much more general.

  16. Presheath profiles in simulated tokamak edge plasmas

    International Nuclear Information System (INIS)

    LaBombard, B.; Conn, R.W.; Hirooka, Y.; Lehmer, R.; Leung, W.K.; Nygren, R.E.; Ra, Y.; Tynan, G.

    1988-04-01

    The PISCES plasma surface interaction facility at UCLA generates plasmas with characteristics similar to those found in the edge plasmas of tokamaks. Steady state magnetized plasmas produced by this device are used to study plasma-wall interaction phenomena which are relevant to tokamak devices. We report here progress on some detailed investigations of the presheath region that extends from a wall surface into these /open quotes/simulated tokamak/close quotes/ edge plasma discharges along magnetic field lines

  17. Engineering analysis of new Brazilian Tokamak

    International Nuclear Information System (INIS)

    Tuszel, A.G.

    1990-01-01

    The engineering basic headlines are described. A project for the construction of a new tokamak is being developed at the Institute of Physics, University of Sao Paulo. The tokamak named TBR-II will be a medium size tokamak using two high power generators of 15 MW each and concepted as a versatile device for plasma physics research of interest for thermonuclear fusion studies. (Author)

  18. A numerical study of tokamak edge turbulence

    International Nuclear Information System (INIS)

    Hu Shuanghui; Huang Lin; Qiu Xiaoming

    1993-01-01

    The tokamak edge turbulence which contains resistivity and impurity gradients and impurity radiation driven sources is studied numerically. The effect of ohmic dissipation on the evolution and saturation of this turbulence is investigated. The ohmic effect drops the saturation levels of fluctuations efficiently in high density tokamaks (such as Alcator), indicating that the ohmic effect plays an important role in the evolution of tokamak edge turbulence in high density devices

  19. Microwave Tokamak Experiment: Overview and status

    International Nuclear Information System (INIS)

    1990-05-01

    The Microwave Tokamak Experiment, now under construction at the Laboratory, will use microwave heating from a free-electron laser. The intense microwave pulses will be injected into the tokamak to realize several goals, including a demonstration of the effects of localized heat deposition within magnetically confined plasma, a better understanding of energy confinement in tokamaks, and use of the new free-electron laser technology for plasma heating. 3 figs., 3 tabs

  20. 78 FR 20029 - Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance...

    Science.gov (United States)

    2013-04-03

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA-HQ-OPP-2013-0057; FRL-9381-2] Castor Oil... from the requirement of a tolerance for residues of castor oil, polymer with adipic acid, linoleic acid... eliminates the need to establish a maximum permissible level for residues of castor oil, polymer with adipic...

  1. Mass spectrometry of the lithium adducts of diacylglycerols containing hydroxy FA in castor oil and two normal FA

    Science.gov (United States)

    Castor oil can be used in industry. The molecular species of triacylglycerols containing hydroxy fatty acids (FA) in castor oil have been identified. We report here the identification of twelve diacylglycerols (DAG) containing hydroxy FA in castor oil using positive ion electrospray ionization mass ...

  2. Comprehensive numerical modelling of tokamaks

    International Nuclear Information System (INIS)

    Cohen, R.H.; Cohen, B.I.; Dubois, P.F.

    1991-01-01

    We outline a plan for the development of a comprehensive numerical model of tokamaks. The model would consist of a suite of independent, communicating packages describing the various aspects of tokamak performance (core and edge transport coefficients and profiles, heating, fueling, magnetic configuration, etc.) as well as extensive diagnostics. These codes, which may run on different computers, would be flexibly linked by a user-friendly shell which would allow run-time specification of packages and generation of pre- and post-processing functions, including workstation-based visualization of output. One package in particular, the calculation of core transport coefficients via gyrokinetic particle simulation, will become practical on the scale required for comprehensive modelling only with the advent of teraFLOP computers. Incremental effort at LLNL would be focused on gyrokinetic simulation and development of the shell

  3. Advanced commercial Tokamak optimization studies

    International Nuclear Information System (INIS)

    Whitley, R.H.; Berwald, D.H.; Gordon, J.D.

    1985-01-01

    Our recent studies have concentrated on developing optimal high beta (bean-shaped plasma) commercial tokamak configurations using TRW's Tokamak Reactor Systems Code (TRSC) with special emphasis on lower net electric power reactors that are more easily deployable. A wide range of issues were investigated in the search for the most economic configuration: fusion power, reactor size, wall load, magnet type, inboard blanket and shield thickness, plasma aspect ratio, and operational β value. The costs and configurations of both steady-state and pulsed reactors were also investigated. Optimal small and large reactor concepts were developed and compared by studying the cost of electricity from single units and from multiplexed units. Multiplexed units appear to have advantages because they share some plant equipment and have lower initial capital investment as compared to larger single units

  4. Flux driven turbulence in tokamaks

    International Nuclear Information System (INIS)

    Garbet, X.; Ghendrih, P.; Ottaviani, M.; Sarazin, Y.; Beyer, P.; Benkadda, S.; Waltz, R.E.

    1999-01-01

    This work deals with tokamak plasma turbulence in the case where fluxes are fixed and profiles are allowed to fluctuate. These systems are intermittent. In particular, radially propagating fronts, are usually observed over a broad range of time and spatial scales. The existence of these fronts provide a way to understand the fast transport events sometimes observed in tokamaks. It is also shown that the confinement scaling law can still be of the gyroBohm type in spite of these large scale transport events. Some departure from the gyroBohm prediction is observed at low flux, i.e. when the gradients are close to the instability threshold. Finally, it is found that the diffusivity is not the same for a turbulence calculated at fixed flux than at fixed temperature gradient, with the same time averaged profile. (author)

  5. Starfire: a commercial tokamak reactor

    International Nuclear Information System (INIS)

    Baker, C.C.; Abdou, M.A.; DeFreece, D.A.; Trachsel, C.A.; Graumann, D.; Kokoszenski, J.

    1979-01-01

    The basic objective of the STARFIRE Project is to develop a design concept for a commercial tokamak fusion electric power plant based on the deuterium/tritium/lithium fuel cycle. The key technical objective is to develop the best embodiment of the tokamak as a power reactor consistent with credible engineering solutions to design problems. Another key goal of the project is to give careful attention to the safety and environmental features of a commercial fusion reactor. The STARFIRE Project was initiated in May 1979, with the goal of completing the design study by October 1980. The purpose of this paper is to present an overview of the major parameters and design features that have been tentatively selected for STARFIRE

  6. Shear Alfven waves in tokamaks

    International Nuclear Information System (INIS)

    Kieras, C.E.

    1982-12-01

    Shear Alfven waves in an axisymmetric tokamak are examined within the framework of the linearized ideal MHD equations. Properties of the shear Alfven continuous spectrum are studied both analytically and numerically. Implications of these results in regards to low frequency rf heating of toroidally confined plasmas are discussed. The structure of the spatial singularities associated with these waves is determined. A reduced set of ideal MHD equations is derived to describe these waves in a very low beta plasma

  7. Equilibrium Reconstruction in EAST Tokamak

    International Nuclear Information System (INIS)

    Qian Jinping; Wan Baonian; Shen Biao; Sun Youwen; Liu Dongmei; Xiao Bingjia; Ren Qilong; Gong Xianzu; Li Jiangang; Lao, L. L.; Sabbagh, S. A.

    2009-01-01

    Reconstruction of experimental axisymmetric equilibria is an important part of tokamak data analysis. Fourier expansion is applied to reconstruct the vessel current distribution in EFIT code. Benchmarking and testing calculations are performed to evaluate and validate this algorithm. Two cases for circular and non-circular plasma discharges are presented. Fourier expansion used to fit the eddy current is a robust method and the real time EFIT can be introduced to the plasma control system in the coming campaign. (magnetically confined plasma)

  8. Dipole Map For Divertor Tokamaks

    International Nuclear Information System (INIS)

    Ali, Halima; Punjabi, Alkesh; Boozer, Allen

    2003-01-01

    Heat flux impinging on the collector plates of divertor tokamaks can be prodigious. Therefore, the problem of spreading the heat flux on plates is a crucial issue for divertor tokamaks such as ITER. Here we use method of maps /1,2/ to investigate this problem. Magnetic field lines in non-axisymmetric divertor tokamaks are a one and a half degree of freedom Hamiltonian system /1-3/. We represent the unperturbed magnetic topology by the Symmetric Simple Map (SSM) /4/ given by yn+1 = yn + 2kxn - 2k2yn (1 - yn), xn+1 = xn - kyn (1 - yn) - 2k2yn+1 (1 - yn+1). The effects of a current carrying coil placed externally across from X-point is represented by Dipole Map (DP) /4,5/ given by x n+1 = x n + 2δs 3 x n+1 (y n - y s + s/[x n+1 2 + (y n - y s + s) 2 ] 2 ), y n+1 = y n + δs 3 x n+1 ((y n - y s + s) 2 - x n+1 2 /[x n+1 2 + (y n - y s + s) 2 ] 2 ) δ is amplitude of high MN magnetic perturbation, s is the distance of coil from last good surface across from X point, and is the y coordinate of last good surface where it crosses the axis joining X point and O point across from X point. We fix k=0.3 and s = (1/2)|y s |. We calculate the increase in width of stochastic layer and area of footprint of field lines on divertor plate as δ is increased. We also calculate how connection length, toroidal and poloidal circuits and their fractal structures, the number, location and density of hot spots change with δ. Finally, we make conclusions about how the heat flux can be possibly controlled and reduced by applying external magnetic perturbation in divertor tokamaks

  9. Relaxed states of tokamak plasmas

    International Nuclear Information System (INIS)

    Kucinski, M.Y.; Okano, V.

    1993-01-01

    The relaxed states of tokamak plasmas are studied. It is assumed that the plasma relaxes to a quasi-steady state which is characterized by a minimum entropy production rate, compatible with a number of prescribed conditions and pressure balance. A poloidal current arises naturally due to the anisotropic resistivity. The minimum entropy production theory is applied, assuming the pressure equilibrium as fundamental constraint on the final state. (L.C.J.A.)

  10. Studies on the Effect of Wet Castor Leaf Feeding and Feeding ...

    African Journals Online (AJOL)

    Rearing of castor feeding silkworm by giving tender wet leaf daily twice at young age (1st and 2nd instars)) and matured wet castor plant leaf daily thrice for late age (3rd, 4th and 5th instars) silkworm significantly reduced the larval duration and diseases incidences and improved all the larval, cocoon and silk traits as ...

  11. Effect of powdered castor oil seed ( Ricinus communis L.) on some ...

    African Journals Online (AJOL)

    Effect of powdered castor oil seed ( Ricinus communis L.) on some internal organs of albino rat. ... Four feed formulations were used; powdered castor oil seed and commercial rat feed mixed in ratio 1:1, 1:2, 1:5, 1:10 and ordinary commercial rat feed, which serves as the control.These formulations were given to four ...

  12. Synthesis and membrane performance characterization of self-emulsified waterborne nitrocellulose dispersion modified with castor oil

    Energy Technology Data Exchange (ETDEWEB)

    Su, Xiuxia; Zhao, Qingxiao, E-mail: 934481965@qq.com; Zhang, Dan; Dong, Wei

    2015-11-30

    Graphical abstract: - Highlights: • Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was synthesized successfully. • It is a kind of environment-friendly coatings, in which volatile organic content (VOC) is near zero. • Castor oil used as an internal crosslinking agent for WNC improved the properties of the coating. • When the mass fraction of castor oil to total reactants is 7%, emulsion and the coating are of the best comprehensive performance. - Abstract: Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was designed and successfully synthesized by self emulsification and reaction among isophorone diisocyanate (IPDI) trimer, dimethylol propionic acid (DMPA), nitrocellulose (NC) and castor oil (C.O.). The CWNC was characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA), etc. The particle size of CWNC increased with the increase of mass fraction of castor oil to total reactants, ω (C.O.). The morphology of particles is an approximate core–shell structure indicated by TEM. FTIR confirmed that the reactions (i.e. IPDI trimer and castor oil, IPDI trimer and NC) occurred, the NCO groups of IPDI trimer were consumed totally and the backbone of NC was retained. The water contact angle measurements confirmed that introduced castor oil increased hydrophobicity of the film, thereby increasing the contact angle. TGA revealed that the CWNC film had better thermal resistance.

  13. Identification of minor acylglycerols less polar than triricinolein in castor oil by mass spectrometry

    Science.gov (United States)

    Triacylglycerols in castor oil less polar than triricinolein were identified by electrospray ionization – mass spectrometry using the lithium adducts of the acylglycerols from the HPLC fractions of castor oil. Thirty four new molecular species of acylglycerols containing hydroxy fatty acids in casto...

  14. the use of castor oil as a flame retardant in polyurethane foam

    African Journals Online (AJOL)

    Dr Abdusalam

    ABSTRACT. Thirteen polyurethane foam samples were prepared with varying quantity of castor oil as a reactant with polyisocyanate and their flammability test was carried out using various flame test procedures. Physical properties of the foam samples were found to increase with the increasing in the quantity of castor oil.

  15. Effect of plant and row spacing on the yield and oil contents of castor ...

    African Journals Online (AJOL)

    Castor (Ricinus communis L.) is an industrial non edible oilseed adapted to drier areas. An experiment was conducted in the Central Rift Valley of Ethiopia to determine optimum plant population of castor variety Hiruy. Four plant (50, 60, 70 and 80 cm) and four row spacing (60,80,100 and 120 cm) were arranged in factorial ...

  16. Synthesis and membrane performance characterization of self-emulsified waterborne nitrocellulose dispersion modified with castor oil

    International Nuclear Information System (INIS)

    Su, Xiuxia; Zhao, Qingxiao; Zhang, Dan; Dong, Wei

    2015-01-01

    Graphical abstract: - Highlights: • Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was synthesized successfully. • It is a kind of environment-friendly coatings, in which volatile organic content (VOC) is near zero. • Castor oil used as an internal crosslinking agent for WNC improved the properties of the coating. • When the mass fraction of castor oil to total reactants is 7%, emulsion and the coating are of the best comprehensive performance. - Abstract: Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was designed and successfully synthesized by self emulsification and reaction among isophorone diisocyanate (IPDI) trimer, dimethylol propionic acid (DMPA), nitrocellulose (NC) and castor oil (C.O.). The CWNC was characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA), etc. The particle size of CWNC increased with the increase of mass fraction of castor oil to total reactants, ω (C.O.). The morphology of particles is an approximate core–shell structure indicated by TEM. FTIR confirmed that the reactions (i.e. IPDI trimer and castor oil, IPDI trimer and NC) occurred, the NCO groups of IPDI trimer were consumed totally and the backbone of NC was retained. The water contact angle measurements confirmed that introduced castor oil increased hydrophobicity of the film, thereby increasing the contact angle. TGA revealed that the CWNC film had better thermal resistance.

  17. Methyl esters from vegetable oils with hydroxy fatty acids: Comparison of lesquerella and castor methyl esters

    Science.gov (United States)

    The search for alternative feedstocks for biodiesel as partial replacement for petrodiesel has recently extended to castor oil. In this work, the castor oil methyl esters were prepared and their properties determined in comparison to the methyl esters of lesquerella oil, which in turn is seen as alt...

  18. Acute Toxicity of Castor Oil Bean Extract and Tolerance Level of ...

    African Journals Online (AJOL)

    The experiment was carried out to determine the acute toxicity of raw castor oil bean (Ricinus communis) extract and the tolerance level of raw castor oil bean by broilers. The seeds were ground, defatted with petroleum ether and the residue was subjected to extraction with phosphate-buffered saline. The extract volume ...

  19. Castor oil induces laxation and uterus contraction via ricinoleic acid activating prostaglandin EP3 receptors.

    Science.gov (United States)

    Tunaru, Sorin; Althoff, Till F; Nüsing, Rolf M; Diener, Martin; Offermanns, Stefan

    2012-06-05

    Castor oil is one of the oldest drugs. When given orally, it has a laxative effect and induces labor in pregnant females. The effects of castor oil are mediated by ricinoleic acid, a hydroxylated fatty acid released from castor oil by intestinal lipases. Despite the wide-spread use of castor oil in conventional and folk medicine, the molecular mechanism by which ricinoleic acid acts remains unknown. Here we show that the EP(3) prostanoid receptor is specifically activated by ricinoleic acid and that it mediates the pharmacological effects of castor oil. In mice lacking EP(3) receptors, the laxative effect and the uterus contraction induced via ricinoleic acid are absent. Although a conditional deletion of the EP(3) receptor gene in intestinal epithelial cells did not affect castor oil-induced diarrhea, mice lacking EP(3) receptors only in smooth-muscle cells were unresponsive to this drug. Thus, the castor oil metabolite ricinoleic acid activates intestinal and uterine smooth-muscle cells via EP(3) prostanoid receptors. These findings identify the cellular and molecular mechanism underlying the pharmacological effects of castor oil and indicate a role of the EP(3) receptor as a target to induce laxative effects.

  20. Effect of castor cake and elephant grass composting on edaphic fauna

    Directory of Open Access Journals (Sweden)

    Rafael Nogueira Scoriza

    Full Text Available ABSTRACT: Elephant grass and castor cake when combined can make a promising organic fertilizer. However, castor cake contains potentially toxic chemicals, such as ricin and ricinine. To test potential effects of these chemicals, compost piles of elephant grass ( Pennisetum purpureum Schum. with castor cake were prepared with different C:N ratios (T1 = 40, T2 = 30, T3 = 20; T4 = 30 [control, elephant grass + crotalaria] to evaluate colonization by edaphic fauna and any suppressive effects of castor cake. Soil organisms were collected with Berlese-Tullgren funnels. There were temporal differences between the treatments, and the epigeous fauna was mainly represented by members of the Acari and Entomobryomorpha. Elapsed time is the major factor in determining the composition of the epigeous fauna community associated with composting, indicating that castor cake has no suppressive effect.

  1. Physicochemical and sensory characteristics of milk from goats supplemented with castor or licuri oil.

    Science.gov (United States)

    Pereira, R A G; Oliveira, C J B; Medeiros, A N; Costa, R G; Bomfim, M A D; Queiroga, R C R E

    2010-02-01

    The purpose of this study was to evaluate the influence of castor and licuri palm oils supplemented to milking goats on the physical, chemical, and sensory characteristics of milk. A double Latin square experimental design (5x5) using 10 confined crossbred Moxotó-Alpine goats was performed according to the following treatments: nonsupplemented (control), 3% castor oil, 5% castor oil, 3% licuri oil, and 5% licuri oil. Oils in each treatment were supplemented in the dry matter. Castor oil supplementation reduced the fat content and increased the lactose and density of milk. Considering the sensory analysis, a lower acceptability was observed for milk from goats supplemented with castor oil. On the other hand, licuri oil supplementation led to higher acceptability scores for flavor and odor of goat milk. Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Synthesis and membrane performance characterization of self-emulsified waterborne nitrocellulose dispersion modified with castor oil

    Science.gov (United States)

    Su, Xiuxia; Zhao, Qingxiao; Zhang, Dan; Dong, Wei

    2015-11-01

    Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was designed and successfully synthesized by self emulsification and reaction among isophorone diisocyanate (IPDI) trimer, dimethylol propionic acid (DMPA), nitrocellulose (NC) and castor oil (C.O.). The CWNC was characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA), etc. The particle size of CWNC increased with the increase of mass fraction of castor oil to total reactants, ω (C.O.). The morphology of particles is an approximate core-shell structure indicated by TEM. FTIR confirmed that the reactions (i.e. IPDI trimer and castor oil, IPDI trimer and NC) occurred, the NCO groups of IPDI trimer were consumed totally and the backbone of NC was retained. The water contact angle measurements confirmed that introduced castor oil increased hydrophobicity of the film, thereby increasing the contact angle. TGA revealed that the CWNC film had better thermal resistance.

  3. Characterization and Digestibility of Detoxified Castor Oil Meal for Japanese Quails

    Directory of Open Access Journals (Sweden)

    PA dos Santos

    2015-12-01

    Full Text Available ABSTRACT These experiments were performed to determine the chemical composition, coefficients of nutrient and energy metabolizability, amino acid composition, and cytotoxicity of different castor oil meals subjected to different detoxification processes and added to the diet of Japanese quails. In the trial, 180 46-d-old female Japanese quails were distributed according to a completely randomized design into five treatments and with replicates of six bird each. The treatments consisted of following detoxification methods of castor oil meal: Castor oil meal A (CMA - recovery in alcohol at 80 °C for 20 minutes and drying at 80 °C; castor oil meal B (CMB and C (CMC - recovery in alcohol at 80 °C for 6 minutes, neutralization with 5% NaOH, and drying under direct sunlight sun for two days (CMB or pelleted (CMC; castor oil meal D (CMD - recovery in alcohol at 110 °C for 15 minutes and drying at 110 °C. Castor oil meal was added replacing 20% of the reference diet. There was slight chemical composition variation (1.21% in crude protein, 6% in dry matter, 2.2% in ether extract and 64 kcal/kg in gross energy among the castor oil meals submitted to the different treatments. The castor oil meal submitted to treatment C showed the highest amino acid values. In the cytotoxicity test, treatment D presented lower ricin activity. Castor oil meals A, C, and D may be included in Japanese quail diets; however, castor oil meal D is recommended due to the simplicity its industrial process, its low toxicity, and metabolizability coefficients obtained.

  4. Tokamak plasma position dynamics and feedback control

    International Nuclear Information System (INIS)

    Burenko, L.; Bailey, J.M.

    1983-01-01

    The perturbation equations of a tokamak plasma equilibrium position are developed. Solution of the approximated perturbation equations is carried out. A unique, simple, and useful plasma displacement dynamics transfer function of a tokamak is developed. The dominant time constants of the dynamics transfer function are determined in a symbolic form

  5. Mercier criterion for high-β tokamaks

    International Nuclear Information System (INIS)

    Galvao, R.M.O.

    1984-01-01

    An expression, for the application of the Mercier criterion to numerical studies of diffuse high-β tokamaks (β approximatelly Σ,q approximatelly 1), which contains only leading order contributions in the high-β tokamak approximation is derived. (L.C.) [pt

  6. Magnetic confinement by Tokamak: physical aspects

    International Nuclear Information System (INIS)

    Tachon, J.

    1980-01-01

    After describing the Tokamak configuration concept, the author provides an analysis of the principal physical aspects of this type of installation and concludes by estimating that the Tokamak concept is a 'plausible candidate' as a means of producing controlled thermonuclear fusion [fr

  7. The ARIES-I tokamak reactor study

    International Nuclear Information System (INIS)

    1991-01-01

    This report contains an overview of the Aries-I tokamak reactor study. The following topics are discussed on this tokamak: Systems studies; equilibrium, stability, and transport; summary and conclusions; current drive; impurity control system; tritium systems; magnet engineering; fusion-power-core engineering; power conversion; Aries-I safety design and analysis; design layout and maintenance; and start-up and operations

  8. TGV, hutě a tokamak ITER

    Czech Academy of Sciences Publication Activity Database

    Řípa, Milan

    Leden (2017) ISSN 2464-7888 Institutional support: RVO:61389021 Keywords : fusion * ITER * tokamak * TGV * Pulse Power Electrical Network * Steady State Electrical Network Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) http://www.3pol.cz/cz/rubriky/jaderna-fyzika-a-energetika/1954-tgv-hute-a-tokamak-iter

  9. Engineering Design of KSTAR tokamak main structure

    International Nuclear Information System (INIS)

    Im, K.H.; Cho, S.; Her, N.I.

    2001-01-01

    The main components of the KSTAR (Korea Superconducting Tokamak Advanced Research) tokamak including vacuum vessel, plasma facing components, cryostat, thermal shield and magnet supporting structure are in the final stage of engineering design. Hundai Heavy Industries (HHI) has been involved in the engineering design of these components. The current configuration and the final engineering design results for the KSTAR main structure are presented. (author)

  10. Castor oil biodiesel and its blends as alternative fuel

    International Nuclear Information System (INIS)

    Berman, Paula; Nizri, Shahar; Wiesman, Zeev

    2011-01-01

    Intensive production and commercialization of biodiesel from edible-grade sources have raised some critical environmental concerns. In order to mitigate these environmental consequences, alternative oilseeds are being investigated as biodiesel feedstocks. Castor (Ricinus communis L.) is one of the most promising non-edible oil crops, due to its high annual seed production and yield, and since it can be grown on marginal land and in semi-arid climate. Still, few studies are available regarding its fuel-related properties in its pure form or as a blend with petrodiesel, many of which are due to its extremely high content of ricinoleic acid. In this study, the specifications in ASTM D6751 and D7467 which are related to the fatty acid composition of pure castor methyl esters (B100) and its blend with petrodiesel in a 10% vol ratio (B10) were investigated. Kinematic viscosity and distillation temperature of B100 (15.17 mm 2 s -1 and 398.7 o C respectively) were the only two properties which did not meet the appropriate standard limits. In contrast, B10 met all the specifications. Still, ASTM D7467 requires that the pure biodiesel meets the requirements of ASTM D6751. This can limit the use of a wide range of feedstocks, including castor, as alternative fuel, especially due to the fact that in practice vehicles normally use low level blends of biodiesel and petrodiesel. These issues are discussed in depth in the present study. -- Highlights: → CaME can be used as a biodiesel alternative feedstock when blended in petrodiesel. → Due to the high levels of ricinoleic acid maximum blending level is limited to 10%. → Today, CaME blends are not a viable alternative feedstock. → ASTM D7467 requires that pure biodiesel must meet all the appropriate limits.

  11. Safety analysis report for packaging (onsite) Castor GSF cask

    International Nuclear Information System (INIS)

    Clements, E.P.

    1997-01-01

    The CASTOR GSF packaging was designed and fabricated to be a certified Type B(U) packaging and comply with the requirements of the International Atomic Energy Agency (IAEA) for transport of up to five sealed canisters of vitrified radioactive materials. This onsite Safety Analysis Report for Packaging (SARP) provides the analysis and evaluations necessary to demonstrate that the casks, with the canister payload, meet the intent of the Type B packaging regulations set forth in 10 CFR 71 and therefore meet the onsite transportation safety requirements of WHC-CM-2-14, Hazardous Material Packaging and Shipping

  12. LDPE/PHB blends filled with castor oil cake

    Science.gov (United States)

    Burlein, Gustavo A.; Rocha, Marisa C. G.

    2015-05-01

    The response surface methodology (RSM) is a collection of mathematical techniques useful for developing, improving and optimizing process. In this study, RSM technique was applied to evaluate the effect of the components proportion on the mechanical properties of low density polyethylene (LDPE)/ poly (3-hydroxy-butyrate) (PHB) blends filled with castor oil cake (CC). The blends were prepared by melt mixing in a twin screw extruder. Low density polyethylene, poly (3-hydroxy-butyrate) and castor oil pressed cake were represented by the input variables designated as LDPE, PHB and CC, respectively. As it was desirable to consider the largest LDPE content in the ternary system, the components of the mixture were subjected to the following constraints: 0.7 ≤ LDPE ≤ 1.0, 0≤ PHB≤0.3 e 0 ≤ CC ≤0.3. The mechanical properties of the different mixtures were determined by conventional ASTM tests and were evaluated through analysis of variance performed by the Minitab software. Some polynomial equations were tested in order to describe the mechanical behavior of the samples. The quadratic model in pseudo components was selected for describing the tensile behavior because it was the most efficient from a statistical point of view (p-value ≤ 0.05; coefficient of determination (r2) close to 1 and variation inflation factor (VIF) values castor oil cake to LDPE. The morphological study of the materials obtained showed that LDPE/PHB blends are immiscible and form morphological structures with well distinguished phase boundaries between dispersed phase and matrix. Biodegradation was evaluated burying the samples in simulated soil for different periods of time. The LDPE/PHB/CC mixtures with higher content of PHB showed more pronounced degradation. Under the experimental conditions studied the LDPE/CC compositions presented no degradation. However, the loss of mass of the LDPE/PHB/CC mixtures was higher than the loss of mass of the corresponding LDPE/PHB binary blend. This

  13. Isocyanate-functionalized castor oil as a novel bitumen modifier

    OpenAIRE

    Cuadri Vega, Antonio Abad; García Morales, Moisés; Navarro Domínguez, Francisco Javier; Partal López, Pedro

    2013-01-01

    The use of biomaterials from renewable sources in the synthesis of polyurethane-derived polymers is lately receiving great attention from social, environmental and economic standpoints. In this work, prepolymers having different -NCO/-OH ratio were synthesized, by reaction of 4,4´-diphenylmethane diisocyanate (MDI) with castor oil (CO), to be used as modifying agent of asphaltic bitumen. Reactions between MDI and CO, performed with -NCO/-OH molar ratios of 8:1 and 4:1, have led to suitable bi...

  14. Radiographic analysis in castor bean seeds (Ricinus communis L.)

    OpenAIRE

    Carvalho, Maria Laene Moreira de; Alves, Renato Augusto; Oliveira, Luciana Magda De.

    2010-01-01

    Castor bean cropping has great social and economic value, but its production has been affected by factors such as low quality seeds used for sowing. The quick and precise evaluation of seed quality by x-ray test is known as an effective method to evaluate seed lots, but little is known about the interpretation between of the type of radiographic image and the seed quality correlation. The potential of x-ray analysis as a marker of seed physiological quality and as an initial process for the i...

  15. Plasma detachment in divertor tokamaks

    Science.gov (United States)

    Leonard, A. W.

    2018-04-01

    Observations of divertor plasma detachment in tokamaks are reviewed. Plasma detachment is characterized in terms of transport and dissipation of power, momentum and particle flux along the open field lines from the midplane to the divertor. Asymmetries in detachment onset and other characteristics between the inboard and outboard divertor plasmas is found to be primarily driven by plasma E× B drifts. The effect of divertor plate geometry and magnetic configuration on divertor detachment is summarized. Control of divertor detachment has progressed with a development of a number of diagnostics to characterize the detached state in real-time. Finally the compatibility of detached divertor operation with high performance core plasmas is examined.

  16. The microwave Tokamak experiment (MTX)

    International Nuclear Information System (INIS)

    Thomassen, K.I.; Cohen, B.I.; Hooper, E.B.; Lang, D.D.; Nevins, W.M.

    1987-01-01

    A new experimental facility is being assembled at the Lawrence Livermore National Laboratory (LLNL) for studying microwave propagation and absorption in high density plasmas. A unique feature of the facility is the free electron laser (FEL) used to generate high peak power microwaves at 250 GHz, at a repetition rate so as to produce up to 2 MW of average power for up to 30 s. Called the Microwave Tokamak Experiment (MTX), the facility will be used for studies of plasma heating, current drive, and confinement

  17. Cluster storage for COMPASS tokamak

    Czech Academy of Sciences Publication Activity Database

    Písačka, Jan; Hron, Martin; Janky, Filip; Pánek, Radomír

    2012-01-01

    Roč. 87, č. 12 (2012), s. 2238-2241 ISSN 0920-3796. [IAEA Technical Meeting on Control, Data Acquisition, and Remote Participation for Fusion Research/8./. San Francisco, 20.06.2011-24.06.2011] R&D Projects: GA ČR GAP205/11/2470; GA MŠk 7G10072; GA MŠk(CZ) LM2011021 Institutional research plan: CEZ:AV0Z20430508 Keywords : COMPASS * Tokamak * Codac * Cluster * GlusterFS * Storage Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.842, year: 2012 http://dx.doi.org/10.1016/j.fusengdes.2012.09.006

  18. Example of industrial valorisation of derivative products of Castor oil

    Directory of Open Access Journals (Sweden)

    Borg Patrick

    2009-07-01

    Full Text Available Known since antiquity, Castor Oil has been first used in medicine. Now, even if it remains present in small quantities as an excipient in many pharmaceutical specialties, it finds a lot of applicationsin cosmetics, industrial applications and chemical industry. Castor Oil specificity comes from its high content of ricinoleic acid (up to 85% that combines a double bond and an hydroxyl function in the heart of a 18 carbons linear chain. This particular structure is the key of an unique chemistry developed by ARKEMA that gives by thermal cracking a wide range of compounds with either 7 or 11 carbon atoms. A whole range of innovative chemistries and end use products are generated from these base reaction products. They are used in every-day life, to improve our comfort and safety but also in very specific applications with very high technical requirements. Synthesized from undecylenic acid, 11-amino-undecanoic acid, 100% based on renewable resources, is the precursor to biobased polymers combining high performance and sustainability: Rilsan®, Rilsan Fine Powder®, Pebax Rnew®.

  19. Characterization of Novel Castor Oil-Based Polyurethane Polymer Electrolytes

    Directory of Open Access Journals (Sweden)

    Salmiah Ibrahim

    2015-04-01

    Full Text Available Castor oil-based polyurethane as a renewable resource polymer has been synthesized for application as a host in polymer electrolyte for electrochemical devices. The polyurethane was added with LiI and NaI in different wt% to form a film of polymer electrolytes. The films were characterized by using attenuated total reflectance-Fourier transform infrared spectroscopy, dynamic mechanical analysis, electrochemical impedance spectroscopy, linear sweep voltammetry and transference number measurement. The highest conductivity of 1.42 × 10−6 S cm−1 was achieved with the addition of 30 wt% LiI and 4.28 × 10−7 S·cm−1 upon addition of 30 wt% NaI at room temperature. The temperature dependence conductivity plot indicated that both systems obeyed Arrhenius law. The activation energy for the PU-LiI and PU-NaI systems were 0.13 and 0.22 eV. Glass transition temperature of the synthesized polyurethane decreased from −15.8 °C to ~ −26 to −28 °C upon salts addition. These characterizations exhibited the castor oil-based polyurethane polymer electrolytes have potential to be used as alternative membrane for electrochemical devices.

  20. Higroscopic properties of castor seeds (Ricinus Comunis L.

    Directory of Open Access Journals (Sweden)

    M. C. Gely

    2009-03-01

    Full Text Available Sorption isotherms of castor seeds were evaluated at 30, 40, 50 and 60ºC using the static gravimetric method. Sigmoid trends were observed for isotherms obtained showing a clear effect of temperature. Experimental values were adjusted using the modified isotherms of Henderson, Halsey, Oswin and Guggenheim-Anderson-de Boer (GAB. Models were compared using four statistics parameters. The results showed that Modified Henderson model adjusted adequately the experimental values in the range of temperature evaluated. The experimental values of the safe storage moisture content for castor seeds varied between 6.1 to 8.4 % (d.b. between 20 and 40ºC, showing lower values than those reported for other traditional oilseeds as sunflower or rapeseed. The sorption heats evaluated from the combination of Clapeyron equation and Modified Henderson equation varied between 3400 and 2373 kJ/kg for moisture contents between 1 and 28 % (d.b.. Through Othmer relationship the value of the ratio Lb/Lf varied between 1.01 and 1.34 (for 14.5 and 1% d.b. moisture content respectively. The values obtained showed an exponential relationship with moisture content, of the form Lb/Lf=1+0.44exp(-0.17M with a determination coefficient R² of 0.97.

  1. Nuclear fusion research at Tokamak Energy Ltd

    International Nuclear Information System (INIS)

    Windridge, Melanie J.; Gryaznevich, Mikhail; Kingham, David

    2017-01-01

    Tokamak Energy's approach is close to the mainstream of nuclear fusion, and chooses a spherical tokamak, which is an economically developed form of Tokamak reactor design, as research subjects together with a high-temperature superconducting magnet. In the theoretical prediction, it is said that spherical tokamak can make tokamak reactor's scale compact compared with ITER or DEMO. The dependence of fusion energy multiplication factor on reactor size is small. According to model studies, it has been found that the center coil can be protected from heat and radiation damage even if the neutron shielding is optimized to 35 cm instead of 1 m. As a small tokamak with a high-temperature superconducting magnet, ST25 HTS, it demonstrated in 2015 continuous operation for more than 24 hours as a world record. Currently, this company is constructing a slightly larger ST40 type, and it is scheduled to start operation in 2017. ST40 is designed to demonstrate that it can realize a high magnetic field with a compact size and aims at attaining 8-10 keV (reaching the nuclear fusion reaction temperature at about 100 million degrees). This company will verify the startup and heating technology by the coalescence of spherical tokamak expected to have plasma current of 2 MA, and will also use 2 MW of neutral particle beam heating. In parallel with ST40, it is promoting a development program for high-temperature superconducting magnet. (A.O.)

  2. Channels in tokamak reactor shields

    International Nuclear Information System (INIS)

    Shchipakin, O.L.

    1981-01-01

    The results of calculations of neutron transport through the channels in the tokamak reactor radiation shields, obtained by the Monte Carlo method and by the method of discrete ordinates, are considered. The given data show that the structural materials of the channel and that of the blanket and shields in the regions close to it are subjected to almost the same irradiation as the first wall and therefore they should satisfy the technical requirements. The radiation energy release in the injector channel wall, caused by neutron shooting, substantially depends on the channel dimensions. At the channel large diameter (0.7-10 m) this dependence noticeably decreases. The investigation of the effect of the injector channel cross section form on the neutron flux density through the channel, testifies to weak dependence of shooting radiation intensity on the form of the channel cross section. It is concluded that measures to decrease unfavourable effect of the channels on the safety of the power tokamak reactor operation and maintenance cause substantial changes in reactor design due to which the channel protection must be developed at first stages. The Monte Carlo method is recommended to be used for variant calculations and when calculating the neutron flux functionals in specific points of the system the discrete ordinate method is preferred [ru

  3. CAT-D-T tokamaks

    International Nuclear Information System (INIS)

    Greenspan, E.; Blue, T.; Miley, G.H.

    1981-01-01

    The domains of plasma fuel cycles bounded by the D-T and Cat-D, and by the D-T and SCD modes of operation are examined. These domains, referred to as, respectively, the Cat-D-T and SCD-T modes of operation, are characterized by the number (γ) of tritons per fusion neutron available from external (to the plasma) sources. Two external tritium sources are considered - the blankets of the Cat-D-T (SCD-T) reactors and fission reactors supported by the Cat-D-T (SCD-T) driven hybrid reactors. It is found that by using 6 Li for the active material of the control elements of the fission reactors, it is possible to achieve γ values close to unity. Cat-D-T tokamaks could be designed to have smaller size, higher power density, lower magnetic field and even lower plasma temperature than Cat-D tokamaks; the difference becomes significant for γ greater than or equal to .75. The SCD-T mode of operation appears to be even more attractive. Promising applications identified for these Cat-D-T and SCD-T modes of operation include hybrid reactors, fusion synfuel factories and fusion reactors which have difficulty in providing all their tritium needs

  4. Plasma position control in TCABR Tokamak

    International Nuclear Information System (INIS)

    Galvao, R.M.O.; Kuznetsov, Yu. K.; Nascimento, I.C.; Fonseca, A.M.M.; Silva, R.P. da; Ruchko, L.F.; Tuszel, A.G.; Reis, A.P. dos; Sanada, E.K.

    1998-01-01

    The plasma control position in the TCABR tokamak is described. The TCA tokamak was transferred from the Centre de Recherches en Physique des Plasmas, Lausanne, to the Institute of Physics of University of Sao Paulo, renamed TCABR (α=0.18 m, R = 0.62 m, B = 1 T,I p = 100 kA). The control system was reconstructed using mainly components obtained from the TCA tokamak. A new method of plasma position determination is used in TCABR to improve its accuracy. A more detailed theoretical analysis of the feed forward and feedback control is performed as compared with. (author)

  5. Estimation of Zeff in Novillo Tokamak

    International Nuclear Information System (INIS)

    Valencia, R.; Olayo, G.; Cruz, G.; Lopez, R.; Chavez, E.; Melendez, L.; Flores, A.; Gaytan, E.

    1996-01-01

    We estimated the Z eff in the Novillo Tokamak after having applied a HeGDC process through two different methods: anomaly factor and mass spectrometry. The first one gave a Z eff value of 2.07 for a tokamak discharge of 4350 A plasma current and 3 V of loop voltage. By mass spectrometry 30 s after the discharge had finished a Z eff of 4.19 was obtained for the same discharge. By mass spectrometry we observed that the Z eff value is a time function. Furthermore this method is helpful for evaluating the level of impurities after many discharges in Novillo Tokamak. (orig.)

  6. Fast IR diodes thermometer for tokamak

    International Nuclear Information System (INIS)

    Chen Xiangbo

    2001-01-01

    A 30 channel fast IR pyrometry array has been constructed for tokamak, which has 0.5 μs time response, 10 mm diameter spatial resolution and 5 degree C temperature resolution. The temperature measuring range is from 250 degree C to 1200 degree C. The two dimensional temperature profiles of the first wall during both major and minor disruptions can be measured with an accuracy of about 1% measuring temperature, which is adequate for tokamak experiments. This gives a very useful tool for the disruption study, especially for the divertor physics and edge heat flux research on tokamak and other magnetic confinement devices

  7. Unbodied dehydrated castor oil from oil of castor beans cultivated in tropical and sub tropical zones of pakistan

    International Nuclear Information System (INIS)

    Saleem, R.; Sultana, R.; Ambrat, A.; Kandhro, A.

    2014-01-01

    Commercially available castor oil was analysed for specific gravity at 25/25 degree C (0.959), acid value (0.5), iodine value (85), refractive index at 25 degree C (1.4769), viscosity at 25 degree C (6.8), and hydroxyl value (162). Fatty acid composition, including palmitic acid (I. 7%), stearic acid (1.39%), oleic acid (5.73%), linoleic acid (6.25%), and ricinoleic acid (84.2%) was estimated by means of GLC. Unbodied dehydrated castor oil (DCO- 15) 93% was prepared by using sodium bisulphate and sodium bisulphite and other reaction conditions. Unbodied DCO was analysed for iodine value (139), acid value (3.6), refractive index at 25 degree C (1.4820), specific gravity at 25/25 degree C and 30/30 degree C (0.9333 and 0.925) viscosity at 25 degree C and 30 degree C (200 cps and 1.85 poise), respectively. Fatty acid composition was also determined to ascertain the extent of dehydration due to the formation of conjugated linoleic acid (CLA, 36.9%) and non conjugated linoleic acid (NCLA, 46.8%). Ricinoleic acid was estimated as 3.83%. Unbodied DCO-15 was in good conformance with the standard specification of ASTM and other values cited in the literature. (author)

  8. Enzymatic incorporation of caffeoyl into castor oil to prepare the novel castor oil-based caffeoyl structured lipids.

    Science.gov (United States)

    Sun, Shangde; Wang, Ping; Zhu, Sha

    2017-05-10

    In this work, a novel castor oil-based caffeoyl structured lipids was successfully prepared by the enzymatic transesterification using castor oil (CO) as caffeoyl acceptor. During the structured lipids preparation, two competitive reactions, the hydrolysis of CO to form hydrophilic caffeoyl glycerols (CG)+dicaffeoyl glycerols (DCG) and the transesterification of CO with ethyl caffeate (EC) to form lipophilic caffeoyl mono- and di-acylglycerols (CMAG and CDAG), were found. Reaction progress was monitored using HPLC-ESI-MS and HPLC-UV. The effects of by-product ethanol removal and reaction variables on the transesterification and reaction selectivity were evaluated. Results showed that, the activation energies for the transesterification and for the selective formations of CMAG+CDAG and CG+DCG were 57.60kJ/mol, 58.86kJ/mol, and 60.53kJ/mol, respectively. Under the optimal reaction conditions (enzyme load 23%, 90°C, 1:3 molar ratio of EC to CO, and 46.5h), EC conversion and the yield of CMAG+CDAG were 93.68±2.52% and 78.11±1.35%, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Comparative clinical trial of castor oil and diclofenac sodium in patients with osteoarthritis.

    Science.gov (United States)

    Medhi, B; Kishore, K; Singh, U; Seth, S D

    2009-10-01

    A randomized, double-blind, comparative clinical study was conducted to compare the safety and efficacy of castor oil with diclofenac sodium in patients with knee osteoarthritis. Subjects with symptoms of knee osteoarthritis were given a castor oil capsule 0.9 mL (n = 50) thrice daily for 4 weeks or a capsule of diclofenac sodium (n = 50), 50 mg thrice daily for 4 weeks. The subjects completed an overall evaluation of symptom relief at 2 weeks and 4 weeks of completed treatment. The subjects were evaluated by clinical, routine laboratory and radiographic investigations for improvement of disease conditions and also for adverse drug reaction. On completion of 4 weeks treatment it was observed that both drugs were significantly effective in the treatment of knee osteoarthritis (p castor oil there were no adverse effects reported. The present study indicates that castor oil can be used as an effective therapy in primary knee osteoarthritis. (c) 2009 John Wiley & Sons, Ltd.

  10. Isotope labeling-based quantitative proteomics of developing seeds of castor oil seed (Ricinus communis L.)

    DEFF Research Database (Denmark)

    Nogueira, Fábio C S; Palmisano, Giuseppe; Schwämmle, Veit

    2013-01-01

    In this study, we used a mass spectrometry-based quantification approach employing isotopic (ICPL) and isobaric (iTRAQ) labeling to investigate the pattern of protein deposition during castor oil seed (Ricinus communis L.) development, including that of proteins involved in fatty acid metabolism...... give important insights into certain aspects of the biology of castor oil seed development such as carbon flow, anabolism, and catabolism of fatty acid and the pattern of deposition of SSPs, toxins, and allergens such as ricin and 2S albumins. We also found, for the first time, some genes of SSP...... could be mapped to extant castor gene models, considerably expanding the number of proteins so far identified from developing castor seeds. Cluster validation and statistical analysis resulted in 975 protein trend patterns and the relative abundance of 618 proteins. The results presented in this work...

  11. Performance of the CASTOR calorimeter at CMS during Run II of LHC

    CERN Document Server

    Van De Klundert, Merijn H F

    2016-01-01

    The detector has pseudorapidity borders at -5.2 and -6.6. An overview is presented on the various aspects of CASTOR's performance and their relations during LHC Run 2. The equalisation of CASTOR's channels is performed using beam-halo muons. Thereafter, CASTOR's pedestal spectrum is studied. It is shown that noise estimates which are extracted using a fit, give on average a 10\\% lower threshold than statistical estimates. Gain correction factors, which are needed for the intercalibration, are obtained using a statistical, in-situ applicable method. The results of this method are shown to be reasonably consistent with laboratory measurements. Penultimately the absolute calibration is discussed, with emphasis on the relation between the scale uncertainty and CASTOR's alignment. It is shown that the alignment's contribution to the systematic uncerta...

  12. Robust Sliding Mode Control for Tokamaks

    Directory of Open Access Journals (Sweden)

    I. Garrido

    2012-01-01

    Full Text Available Nuclear fusion has arisen as an alternative energy to avoid carbon dioxide emissions, being the tokamak a promising nuclear fusion reactor that uses a magnetic field to confine plasma in the shape of a torus. However, different kinds of magnetohydrodynamic instabilities may affect tokamak plasma equilibrium, causing severe reduction of particle confinement and leading to plasma disruptions. In this sense, numerous efforts and resources have been devoted to seeking solutions for the different plasma control problems so as to avoid energy confinement time decrements in these devices. In particular, since the growth rate of the vertical instability increases with the internal inductance, lowering the internal inductance is a fundamental issue to address for the elongated plasmas employed within the advanced tokamaks currently under development. In this sense, this paper introduces a lumped parameter numerical model of the tokamak in order to design a novel robust sliding mode controller for the internal inductance using the transformer primary coil as actuator.

  13. Research into controlled fusion in tokamaks

    International Nuclear Information System (INIS)

    Zacek, F.

    1992-01-01

    During the thirty years of tokamak research, physicists have been approaching step by step the reactor breakeven condition defined by the Lawson criterion. JET, the European Community tokamak is probably the first candidate among the world largest tokamaks to reach the ignition threshold and thus to demonstrate the physical feasibility of thermonuclear reaction. The record plasma parameters achieved in JET at H plasma modes due to powerful additional plasma heating and due to substantial reduction of plasma impurities, opened the door to the first experiment with a deuterium-tritium plasma. In the paper, the conditions and results of these tritium experiments are described in detail. The prospects of the world tokamak research and of the participation of Czechoslovak physicists are also discussed. (J.U.) 3 figs., 6 refs

  14. Theory of incremental turbulent transport in tokamaks

    International Nuclear Information System (INIS)

    Similon, P.L.

    1991-01-01

    The goal of this research is to understand how the various aspect of turbulent transport operate in tokamaks, in the presence of low frequency fluctuations such as drift waves or trapped electron modes

  15. Definition of total bootstrap current in tokamaks

    International Nuclear Information System (INIS)

    Ross, D.W.

    1995-01-01

    Alternative definitions of the total bootstrap current are compared. An analogous comparison is given for the ohmic and auxiliary currents. It is argued that different definitions than those usually employed lead to simpler analyses of tokamak operating scenarios

  16. Tokamak research in the Soviet Union

    International Nuclear Information System (INIS)

    Strelkov, V.S.

    1981-01-01

    Important milestones on the way to the tokamak fusion reactor are recapitulated. Soviet tokamak research concentrated at the I.V. Kurchatov Institute in Moscow, the A.F. Ioffe Institute in Leningrad and the Physical-Technical Institute in Sukhumi successfully provides necessary scientific and technological data for reactor design. Achievments include, the successful operation of the first tokamak with superconducting windings (T-7) and the gyrotron set for microwave plasma heating in the T-10 tokamak. The following problems have intensively been studied: Various methods of additional plasma heating, heat and particle transport, and impurity control. The efficiency of electron-cyclotron resonance heating was demonstrated. In the Joule heating regime, both the heat conduction and diffusion rates are anomalously high, but the electron heat conduction rate decreases with increasing plasma density. Progress in impurity control makes it possible to obtain a plasma with effective charge approaching unity. (J.U.)

  17. Plasma equilibrium and instabilities in tokamaks

    International Nuclear Information System (INIS)

    Caldas, I.L.; Vannucci, A.

    1985-01-01

    A phenomenological introduction of some of the main theoretical and experimental features on equilibrium and instabilities in tokamaks is presented. In general only macroscopic effects are considered, being the plasma described as a fluid. (L.C.) [pt

  18. The ARIES-I tokamak reactor study

    International Nuclear Information System (INIS)

    1991-01-01

    This report discusses the following topics on the Aries-I Tokamak: Design description; systems studies and economics; reactor plasma physics; magnet engineering; fusion-power-ore engineering; and environmental and safety features

  19. Submillimeter wave propagation in tokamak plasmas

    International Nuclear Information System (INIS)

    Ma, C.H.; Hutchinson, D.P.; Staats, P.A.; Vander Sluis, K.L.; Mansfield, D.K.; Park, H.; Johnson, L.C.

    1986-01-01

    Propagation of submillimeter waves (smm) in tokamak plasma was investigated both theoretically and experimentally to ensure successful measurements of electron density and plasma current distributions in tokamak devices. Theoretical analyses were carried out to study the polarization of the smm waves in TFTR and ISX-B tokamaks. A multichord smm wave interferometer/polarimeter system was employed to simultaneously measure the line electron density and poloidal field-induced Faraday rotation in the ISX-B tokamak. The experimental study on TFTR is under way. Computer codes were developed and have been used to study the wave propagation and to reconstruct the distributions of plasma current and density from the measured data. The results are compared with other measurements. 5 references, 2 figures

  20. Power and particle exhaust in tokamaks

    International Nuclear Information System (INIS)

    Stambaugh, R.D.

    1998-01-01

    The status of power and particle exhaust research in tokamaks is reviewed in the light of ITER requirements. There is a sound basis for ITER's nominal design positions; important directions for further research are identified

  1. Bio-based polyurethane prepared from Kraft lignin and modified castor oil

    OpenAIRE

    L. B. Tavares; C. V. Boas; G. R. Schleder; A. M. Nacas; D. S. Rosa; D. J. Santos

    2016-01-01

    Current challenges highlight the need for polymer research using renewable natural sources as a substitute for petroleum-based polymers. The use of polyols obtained from renewable sources combined with the reuse of industrial residues such as lignin is an important agent in this process. Different compositions of polyurethane-type materials were prepared by combining technical Kraft lignin (TKL) with castor oil (CO) or modified castor oil (MCO1 and MCO2) to increase their reactivity towards d...

  2. Preliminary results of the TBR small tokamak

    International Nuclear Information System (INIS)

    Nascimento, I.C.; Fagundes, A.N.; Da Silva, R.P.; Galvao, R.M.O.; Del Bosco, E.; Vuolo, J.H.; Sanada, E.K.; Dellaqua, R.

    1982-01-01

    The paper gives a short description of the TBR - small Brazilian tokamak and the first results obtained for plasma formation and equilibrium. Measured breakdown curves for hydrogen are shown to be confined within analytically calculated limits and to depend strongly on stray vertical magnetic fields. Time profiles of plasma current in equilibrium are shown and compared with the predictions of a simple analytical model for tokamak discharges. Reasonable agreement is obtained taking Zsub(eff) as a free parameter. (author)

  3. The ETE spherical Tokamak project. IAEA report

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Gerson Otto; Del Bosco, E.; Berni, L.A.; Ferreira, J.G.; Oliveira, R.M.; Andrade, M.C.R.; Shibata, C.S.; Barroso, J.J.; Castro, P.J.; Patire Junior, H. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Lab. Associado de Plasma]. E-mail: ludwig@plasma.inpe.br

    2002-07-01

    This paper describes the general characteristics of spherical tokamaks, or spherical tori, with a brief overview of work in this area already performed or in progress at several institutions worldwide. The paper presents also the historical development of the ETE (Spherical Tokamak Experiment) project, its research program, technical characteristics and operating conditions as of October, 2002 at the Associated Plasma Laboratory (LAP) of the National Space Research Institute (INPE) in Brazil. (author)

  4. Experimental and empirical study of diesel and castor biodiesel blending effect, on kinematic viscosity, density and calorific value

    Directory of Open Access Journals (Sweden)

    A. Amin

    2016-12-01

    Full Text Available This study aimed to investigate the fuel properties like density, viscosity and calorific value of trans-esterified methyl ester using castor biodiesel and their blends with No. 2 diesel. Empirical correlations are proposed to predict the kinematic viscosity, density, and calorific value for a mixture of castor oil and No. 2 diesel. Kay mixing rule shows a good prediction for the fuel properties under study. Several polynomials are fitted using least square method, and the fitted equations show a good agreement with the experimental data from our study. The developed equations could be used as universal formulas to predict the kinematic viscosity, density, and calorific value for castor oil and No. 2 diesel blend. The equations can be used to optimize the mixing ratio of the castor oil/No. 2 diesel for different applications. Blending of castor oil with No. 2 diesel- in the range of 20% castor oil, will not violate the required specification of diesel engines.

  5. Some properties of castor oil affecting its performance as a capacitor impregnant and their significance to future impregnant research

    International Nuclear Information System (INIS)

    Boicourt, G.P.

    1975-01-01

    For a considerable time castor oil and polychlorinated biphenyl (PCB) have been the principal impregnants used in energy-storage capacitors. Castor oil has proven to be better than PCB for pulsed applications. PCB's have come under attack as an environmental hazard, while castor oil is a vegetable product and its supply and quality are subject to fluctuation. These two facts make the development of new impregnants desirable. The properties of PCB as a capacitor impregnant are well known. This paper first compares a number of properties of castor oil and PCB's. A comparison is made between the lives of castor oil capacitors and comparable PCB energy-storage capacitors. Some of the physical and chemical properties of castor oil which make it a good pulse capacitor impregnant are examined. These properties can be used as a guide for future research on new pulse capacitor impregnants

  6. Castor and Pollux - shielded cells for studying fuel treatment processes

    International Nuclear Information System (INIS)

    Faudot, G.; Bathellier, A.

    1969-01-01

    CASTOR and POLLUX, two alpha, beta, gamma cells are described in the present paper. They are located in the CEN at Fontenay-aux-Roses (France). They are designed for improvement studies of the various aqueous separation processes used in irradiated fuels reprocessing plants. Located in the same air-tight steel encasement, they arc inter-connected by a pneumatic transfer. These two cells have a similar in-line conception and they include: a gamma shielding in lead of 10 cm of thickness; an inner air-tight box, made with stainless steel and plexiglas, is maintained in lowering in comparison to room pressure. Eleven Hobson model seven master-slave manipulators allow inner manipulations. Then the inner equipment is described briefly. (author) [fr

  7. ARTICLE - Inbreeding depression in castor bean (Ricinus communis L. progenies

    Directory of Open Access Journals (Sweden)

    Milton Krieger

    2012-12-01

    Full Text Available The purpose of this study was to investigate inbreeding depression (DE in castor bean. From a population derived from the Guarani cultivar, 60 mother plants were sampled. Three types of progenies were obtained from each one: from self-pollination (AU, from crosses (CR and from open pollination (PL. Grain yield of the progenies was evaluated in two locations. There was a strong interaction of progenies x locations, which led to obtaining estimates within each location. Broad variation was observed in inbreeding depression, with mean values of 6.7% and 13.4%, comparing AU progenies with PL progenies. It was observed that the population has high potential for selecting promising inbred lines. The frequency of mother plants generating progenies with simultaneous high general combination capacity and low inbreeding depression was low. Recurrent selection will increase the occurrence of parent plants associating these two properties, which is necessary for obtaining superior synthetic varieties.

  8. Ingestive behavior of lambs fed diets containing castor seed meal.

    Science.gov (United States)

    Nicory, Isis Miranda Carvalho; de Carvalho, Gleidson Giordano Pinto; Ribeiro, Ossival Lolato; Silva, Robério Rodrigues; Tosto, Manuela Silva Libanio; Costa-Lopes, Lívia Santos; Souza, Fábio Nicory Costa; de Oliveira Nascimento, Camila

    2015-06-01

    The objective of this study was to evaluate the substitution of soybean meal for castor seed meal (CSM) in diets for feedlot lambs and the effects of these diets on their ingestive behavior. Fifty male Santa Inês lambs were used. The diets were composed of Tifton 85 hay and a concentrate containing detoxified CSM substituting 0, 25, 50, 75, or 100 % of the soybean meal. There was no effect (P > 0.05) of the CSM levels on the feeding, rumination, idle times, chews and time spent chewing per bolus, total chewing time, number of boli chewed, and number of chews per day. The dry matter (DM) intake decreased linearly (P  0.05) the numbers of feeding, rumination, and idle periods, but had a quadratic effect (P ingestive behavior.

  9. Castor oil polyurethane containing silica nanoparticles as filling material of bone defect in rats.

    Science.gov (United States)

    Nacer, Renato Silva; Poppi, Rodrigo Ré; Carvalho, Paulo de Tarso Camilo de; Silva, Baldomero Antonio Kato da; Odashiro, Alexandre Nakao; Silva, Iandara Schettert; Delben, José Renato Jurkevicz; Delben, Angela Antonia Sanches Tardivo

    2012-01-01

    To evaluate the biologic behavior of the castor polymer containing silica nanoparticles as a bone substitute in diafisary defect. Twenty seven male Rattus norvegicus albinus Wistar lineage were submitted to bone defect filled with castor oil polymer. Three experimental groups had been formed with nine animals each: (1) castor oil polymer containing only calcium carbonate; (2) castor oil polymer with calcium carbonate and doped with 5% of silica nanoparticles; (3) castor polymer with calcium carbonate doped with 10% of silica nanoparticles; 3 animals of each group were submitted to euthanasia 15, 30 and 60 days after experimental procedure, and their femurs were removed to histological evaluation. there was bone growth in all the studied groups, with a greater tendency of growth in the group 1. After 30 days all the groups presented similar results. After 60 days a greater amount of fibroblasts, osteoblasts, osteocytes and osteoclasts in group 3 was observed, with integrated activity of 3 kinds of cells involved in the bone activation-reabsorption-formation. The castor polymer associated to the silica nanoparticles is biocompatible and allows osteoconduction. The presence of osteoprogenitors cells suggests silica osteoinduction capacity.

  10. Secure and documented screwing down of Castor containers

    International Nuclear Information System (INIS)

    Yilmaz, Asir; Junkers, Patrick

    2011-01-01

    The castor container is sealed using a multiple lid system comprising a primary lid and a secondary lid. The two lids are positioned one above the other and screwed securely to the body of the container. In addition, the tightness of the lids is guaranteed by a special metal seal. A further steel plate is screwed securely over the lids providing additional protection for the lids from moisture and various influences. The central element connecting the lids to the container comprises fixed threaded connections which must be accurately tightened with a torque of 900 Nm, 1500 Nm or more. The basic function of a threaded connection, in terms of a positive fit and detachable joint, is to join together two or more parts in such a way that they always behave as a single part whatever operational forces are present. This can only be achieved by means of an accurate and sufficient pre-tensioning force. This pretensioning force is transferred to the threaded connection with the help of a particular torque and presses the components together. This loading brought about by the pretensioning force is referred to as the prestress. In order to create a correct and high quality connection, this prestress must be arrived at in an optimum manner. The prestress must therefore be high enough to withstand the full loading for which the connection is designed. In addition the connection should not come loose unintentionally if it is exposed to externally acting forces. Since under no circumstances should threaded connections on a castor container fail, a suitable screwing process must guarantee that this does not happen. The securing of threaded joints can only be ensured by introducing and maintaining a constant and accurate prestress. VDI Guideline 2230, Part 1, mentions various threaded connection or tightening processes, including torque-controlled tightening, angle-controlled tightening and yield-controlled tightening. (orig.)

  11. Screening of the entire USDA castor germplasm collection for oil content and fatty acid composition for optimum biodiesel production.

    Science.gov (United States)

    Wang, Ming Li; Morris, J Bradley; Tonnis, Brandon; Pinnow, David; Davis, Jerry; Raymer, Paul; Pederson, Gary A

    2011-09-14

    Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors determining the price for production and affecting the key fuel properties of biodiesel. There are 1033 available castor accessions collected or donated from 48 countries worldwide in the USDA germplasm collection. The entire castor collection was screened for oil content and fatty acid composition by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Castor seeds on the average contain 48.2% oil with significant variability ranging from 37.2 to 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was composed primarily of eight fatty acids: 1.48% palmitic (C16:0), 1.58% stearic (C18:0), 4.41% oleic (C18:1), 6.42% linoleic (C18:2), 0.68% linolenic (C18:3), 0.45% gadoleic (C20:1), 84.51% ricinoleic (C18:1-1OH), and 0.47% dihydroxystearic (C18:0-2OH) acids. Significant variability in fatty acid composition was detected among castor accessions. Ricinoleic acid (RA) was positively correlated with dihydroxystearic acid (DHSA) but highly negatively correlated with the five other fatty acids except linolenic acid. The results for oil content and fatty acid composition obtained from this study will be useful for end-users to explore castor germplasm for biodiesel production.

  12. Castor oil, bath and/or enema for cervical priming and induction of labour.

    Science.gov (United States)

    Kelly, Anthony J; Kavanagh, Josephine; Thomas, Jane

    2013-07-24

    Castor oil, a potent cathartic, is derived from the bean of the castor plant. Anecdotal reports, which date back to ancient Egypt have suggested the use of castor oil to stimulate labour. Castor oil has been widely used as a traditional method of initiating labour in midwifery practice. Its role in the initiation of labour is poorly understood and data examining its efficacy within a clinical trial are limited. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. To determine the effects of castor oil or enemas for third trimester cervical ripening or induction of labour in comparison with other methods of cervical ripening or induction of labour. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2013) and bibliographies of relevant papers. Clinical trials comparing castor oil, bath or enemas used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods. A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. Three trials, involving 233 women, are included. There was no evidence of differences in caesarean section rates between the two interventions in the two trials reporting this outcome (risk ratio (RR) 2.04, 95% confidence interval (CI) 0.92 to 4.55). There were no data presented on neonatal or maternal mortality or morbidity.There was no evidence of a difference between castor oil and placebo/no treatment for the rate of instrumental delivery, meconium-stained liquor, or Apgar score less than seven at five minutes. The number of participants was too small to detect all but large differences in outcome. All women who ingested castor oil felt nauseous (RR 59.92, 95% CI 8.46 to 424.52). The three trials included in the review contain small numbers

  13. Particle and energy balances in tokamak plasmas

    International Nuclear Information System (INIS)

    Tazima, Teruhiko

    1978-06-01

    Computational and experimental studies on particle and energy balances in tokamak plasmas are described. Firstly, concerning the modeling of tokamak plasmas, the particle balance considering diffusion and recycling, and the energy balance considering transport and energy losses due to impurities are discussed. Production mechanisms of gaseous and metallic impurities, which play important role in tokamak plasmas, are also discussed from a viewpoint of plasma-wall interactions. Scaling laws of density, temperature and energy confinement time are shown on the basis of recent data. Secondarily, tokamak plasmas are simulated with the above model, and anomalous diffusion and electron thermal conduction are indicated. Characteristics of a future tokamak plasma are also simulated. Stationary impurity density distributions and related energy losses, such as bremsstrahlung, ionization and excitation, are calculated taking into account diffusion and ionization processes. Edge cooling by oxygen impurities is described quantitatively compared with experiments. Permissible impurity levels of carbon, oxygen and iron in future large tokamaks are estimated. Thirdly, experimental studies on surface cleaning methods of the first wall are described; discharge cleaning in JFT-2, baking effect on the outgassing rates of wall materials, surface treatment of high-temperature molybdenum by oxygen and hydrogen gases, and in-situ coating of molybdenum by a coaxial magnetron sputter method. Lastly, problems in future large tokamaks aiming at break-even or self-ignited plasma are discussed quantitatively, such as trapped particle instabilities, impurities and additional heating. It is predicted that new conceptions will be necessary to overcome the problems and attain the fusion goal. (auth.)

  14. Wave–particle resonances and redistribution/losses of fast ions in tokamaks

    International Nuclear Information System (INIS)

    Nabais, F.; Borba, D.; Kiptily, V.G.; Pinches, S.D.; Sharapov, S.E.

    2012-01-01

    Enhanced fast ion losses, mostly in the range of energies from around 1.2 to 2.4 MeV, were measured during the activity of tornado modes in the JET tokamak. Tornado modes are TAE localized inside the q = 1 surface, which do not extend to the outer regions of the plasma. Thus, it is necessary to find an explanation on how such modes can lead to the loss of fast ions. In this paper, a mechanism that allows explaining the loss of fast ions triggered by tornado modes is proposed. This mechanism is based on the combined effect of tornado modes and global TAEs over the fast ions (global TAEs were always observed along with the tornado modes in the experiments in which enhanced losses were measured). Tornado modes would trigger the process of loss by resonantly interacting with the fast ions near the centre of the plasma and transporting the ions to a more peripheral region where tornado modes and global TAEs coexist. The TAE would then transport convectively the fast ions, most efficiently through the first bounce resonances (p = 1), all the way to the plasma edge eventually leading to its loss. This mechanism of loss is supported by calculations carried out with the CASTOR-K code. (paper)

  15. Analysis of tokamak plasma confinement modes using the fast

    Indian Academy of Sciences (India)

    The Fourier analysis is a satisfactory technique for detecting plasma confinement modes in tokamaks. The confinement mode of tokamak plasma was analysed using the fast Fourier transformation (FFT). For this purpose, we used the data of Mirnov coils that is one of the identifying tools in the IR-T1 tokamak, with and ...

  16. Edge plasma diagnostics on Tore Supra tokamak

    International Nuclear Information System (INIS)

    Fujita, Junji

    1991-01-01

    From 1988 to 1991, the international scientific research 'Diagnosis of peripheral plasma in Tore Supra tokamak' was carried out as a three-year plan receiving the support of the scientific research expense of the Ministry of Education. This is to apply the method of measuring electron density distribution by neutral lithium beam probe spectroscopy to the measurement of the electron density distribution in the peripheral plasma in Tore Supra Tokamak in France. Among many tokamaks in operation doing respective characteristics researches, the Tore Supra generates the toroidal magnetic field by using superconducting coils, and aims at the long time discharge for 30 sec. for the time being, and for 300 sec. in future. In the plasma generators for long time discharge like this, the technology of particle control is a large problem. For this purpose, a divertor was added to the Tore Supra. In order to advance the research on particle control, it is necessary to examine the behavior of plasma in the peripheral part in detail. The measurement of peripheral plasma in tokamaks, beam probe spectroscopy, the Tore Supra tokamak, the progress of the joint research, the problems in the joint research and the perspective of hereafter are reported. (K.I.)

  17. Three novel tokamak plasma regimes in TFTR

    International Nuclear Information System (INIS)

    Furth, H.P.

    1985-10-01

    Aside from extending ''standard'' ohmic and neutral beam heating studies to advanced plasma parameters, TFTR has encountered a number of special plasma regimes that have the potential to shed new light on the physics of tokamak confinement and the optimal design of future D-T facilities: (1) High-powered, neutral beam heating at low plasma densities can maintain a highly reactive hot-ion population (with quasi-steady-state beam fueling and current drive) in a tokamak configuration of modest bulk-plasma confinement requirements. (2) Plasma displacement away from limiter contact lends itself to clarification of the role of edge-plasma recycling and radiation cooling within the overall pattern of tokamak heat flow. (3) Noncentral auxiliary heating (with a ''hollow'' power-deposition profile) should serve to raise the central tokamak plasma temperature without deterioration of central region confinement, thus facilitating the study of alpha-heating effects in TFTR. The experimental results of regime (3) support the theory that tokamak profile consistency is related to resistive kink stability and that the global energy confinement time is determined by transport properties of the plasma edge region

  18. Three novel tokamak plasma regimes in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Furth, H.P.

    1985-10-01

    Aside from extending ''standard'' ohmic and neutral beam heating studies to advanced plasma parameters, TFTR has encountered a number of special plasma regimes that have the potential to shed new light on the physics of tokamak confinement and the optimal design of future D-T facilities: (1) High-powered, neutral beam heating at low plasma densities can maintain a highly reactive hot-ion population (with quasi-steady-state beam fueling and current drive) in a tokamak configuration of modest bulk-plasma confinement requirements. (2) Plasma displacement away from limiter contact lends itself to clarification of the role of edge-plasma recycling and radiation cooling within the overall pattern of tokamak heat flow. (3) Noncentral auxiliary heating (with a ''hollow'' power-deposition profile) should serve to raise the central tokamak plasma temperature without deterioration of central region confinement, thus facilitating the study of alpha-heating effects in TFTR. The experimental results of regime (3) support the theory that tokamak profile consistency is related to resistive kink stability and that the global energy confinement time is determined by transport properties of the plasma edge region.

  19. Electron thermal transport in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Konings, J.A.

    1994-11-30

    The process of fusion of small nuclei thereby releasing energy, as it occurs continuously in the sun, is essential for the existence of mankind. The same process applied in a controlled way on earth would provide a clean and an abundant energy source, and be the long term solution of the energy problem. Nuclear fusion requires an extremely hot (10{sup 8} K) ionized gas, a plasma, that can only be maintained if it is kept insulated from any material wall. In the so called `tokamak` this is achieved by using magnetic fields. The termal insulation, which is essential if one wants to keep the plasma at the high `fusion` temperature, can be predicted using basic plasma therory. A comparison with experiments in tokamaks, however, showed that the electron enery losses are ten to hundred times larger than this theory predicts. This `anomalous transport` of thermal energy implies that, to reach the condition for nuclear fusion, a fusion reactor must have very large dimensions. This may put the economic feasibility of fusion power in jeopardy. Therefore, in a worldwide collaboration, physicists study tokamak plasmas in an attempt to understand and control the energy losses. From a scientific point of view, the mechanisms driving anomalous transport are one of the challenges in fudamental plasma physics. In Nieuwegein, a tokamak experiment (the Rijnhuizen Tokamak Project, RTP) is dedicated to the study of anomalous transport, in an international collaboration with other laboratories. (orig./WL).

  20. Castor (Ricinus communis L. and Pigweed (Amaranthus retroflexus L. Growth Indices in Terms of Interference

    Directory of Open Access Journals (Sweden)

    naser jafarzadeh

    2016-11-01

    Full Text Available Introduction Growth analysis has been widely used in breeding programs to identify the important plant developmental phases and components related to higher yield under a particular set of environmental conditions. Castor bean (Ricinus communis L. is an important commercial crop. Castor oil based by products is used in manufacturing of several commercially important commodities like surfactants, coatings, greases, pharmaceuticals, cosmetics, polyesters, polymers, etc. Interference (Interactive effects among species on inter-species populations is one of the main issues on the eco-physiology of plant populations where weeds impose negative effects by approaching the plant to compete in light, water and nutrient elements availability and results in reduced growth and yield (Shinggu et al., 2011. Growth indices are useful for interpreting plant reactions to the crop and weed density. Various reasons have been attributed for the low productivity among the most important is weed competition (Radosevich, 1987. The aim of the present experiment was evaluating the interference effects of redroot pigweed on growth indices of castor bean in northwest of Iran. Materials and methods This experiment was conducted in Urmia, Iran (Agricultural Research of West Azarbayjan, Saatlo Station (37°44´18״ N Latitude and 45° 10´ 53״ E Longitude, at 1338 m above sea level in 2012. The soil of the experimental field was sandy - loam, with pH of 7.2. Competitive pattern of experiment was in two-factor based on a randomized complete block design (RCBD with three replications arranged in four castor plant densities (3, 4, 5 and 6 plants.m-2 and four redroot pigweed densities (0, 5, 10 and 15 plants.m-2. Redroot pigweed and castor seeds were simultaneously directly planted on the 22th May in 2012. Redroot pigweed plants were weeded at the times related to the treatments level. Irrigation and intercultural operations were performed whenever necessary. Plots were 3m×5m

  1. The collaborative tokamak control room

    International Nuclear Information System (INIS)

    Schissel, D.P.

    2006-01-01

    Magnetic fusion experiments keep growing in size and complexity resulting in a concurrent growth in collaborations between experimental sites and laboratories worldwide. In the US, the National Fusion Collaboratory Project is developing a persistent infrastructure to enable scientific collaboration for all aspects of magnetic fusion energy research by creating a robust, user-friendly collaborative environment and deploying this to the more than 1000 US fusion scientists in 40 institutions who perform magnetic fusion research. This paper reports on one aspect of the project which is the development of the collaborative tokamak control room to enhance both collocated and remote scientific participation in experimental operations. This work includes secured computational services that can be scheduled as required, the ability to rapidly compare experimental data with simulation results, a means to easily share individual results with the group by moving application windows to a shared display, and the ability for remote scientists to be fully engaged in experimental operations through shared audio, video, and applications. The project is funded by the USDOE Office of Science, Scientific Discovery through Advanced Computing (SciDAC) Program and unites fusion and computer science researchers to directly address these challenges

  2. Tokamak disruption heat flux simulator

    International Nuclear Information System (INIS)

    Langhoff, M.; Hess, G.; Gahl, J.; Ingram, R.

    1990-01-01

    A coaxial plasma gun system, operating in the deflagration mode, has been built and fired at the University of New Mexico. This system, powered by a 100 kJ capacitor bank, was designed to give a variable pulse length of approximately 50-100 us. The gun is intended to deliver to a target an energy deposition density of 1 kJ per cm 2 via impact with a deuterium plasma possessing a highly directed energy. This system should simulate on the target, over an area of approximately 10 cm 2 , the heat flux of a tokamak plasma disruption on plasma facing components. Current diagnostics for the system are rather rudimentary but sufficient for determination of plasma pulse characteristics and energy transfer to target. Electrical measurements include bank voltage measured via resistive voltage dividers, and bank current measured via Rogowski coil. The shape of the plasma, its position relative to the target area, and the final impact area, is determined via open-shutter photography and the use of witness plates. Total energy deposited onto targets will be determined through simple calorimetry and careful target mass measurements. Preliminary results describing the ablation of carbon targets exposed to disruption like heat fluxes will be presented as well as a description of the experimental apparatus

  3. Neoclassical MHD equations for tokamaks

    International Nuclear Information System (INIS)

    Callen, J.D.; Shaing, K.C.

    1986-03-01

    The moment equation approach to neoclassical-type processes is used to derive the flows, currents and resistive MHD-like equations for studying equilibria and instabilities in axisymmetric tokamak plasmas operating in the banana-plateau collisionality regime (ν* approx. 1). The resultant ''neoclassical MHD'' equations differ from the usual reduced equations of resistive MHD primarily by the addition of the important viscous relaxation effects within a magnetic flux surface. The primary effects of the parallel (poloidal) viscous relaxation are: (1) Rapid (approx. ν/sub i/) damping of the poloidal ion flow so the residual flow is only toroidal; (2) addition of the bootstrap current contribution to Ohm's laws; and (3) an enhanced (by B 2 /B/sub theta/ 2 ) polarization drift type term and consequent enhancement of the perpendicular dielectric constant due to parallel flow inertia, which causes the equations to depend only on the poloidal magnetic field B/sub theta/. Gyroviscosity (or diamagnetic vfiscosity) effects are included to properly treat the diamagnetic flow effects. The nonlinear form of the neoclassical MHD equations is derived and shown to satisfy an energy conservation equation with dissipation arising from Joule and poloidal viscous heating, and transport due to classical and neoclassical diffusion

  4. Tokamak rotation and charge exchange

    International Nuclear Information System (INIS)

    Hazeltine, R.D.; Rowan, W.L.; Solano, E.R.; Valanju, P.M.

    1991-01-01

    In the absence of momentum input, tokamak toroidal rotation rates are typically small - no larger in particular than poloidal rotation - even when the radial electric field is strong, as near the plasma edge. This circumstance, contradicting conventional neoclassical theory, is commonly attributed to the rotation damping effect of charge exchange, although a detailed comparison between charge-exchange damping theory and experiment is apparently unavailable. Such a comparison is attempted here in the context of recent TEXT experiments, which compare rotation rates, both poloidal and toroidal, in helium and hydrogen discharges. The helium discharges provide useful data because they are nearly free of ion-neutral charge exchange; they have been found to rotate toroidally in reasonable agreement with neoclassical predictions. The hydrogen experiments show much smaller toroidal motion as usual. The theoretical calculation uses the full charge-exchange operator and assumes plateau collisionality, roughly consistent with the experimental conditions. The authors calculate the ion flow as a function of v cx /v c , where v cx is the charge exchange rate and v c the Coulomb collision frequency. The results are in reasonable accord with the observations. 1 ref

  5. Stability analysis of tokamak plasmas

    International Nuclear Information System (INIS)

    Bourdelle, C.

    2000-10-01

    In a tokamak plasma, the energy transport is mainly turbulent. In order to increase the fusion reactions rate, it is needed to improve the energy confinement. The present work is dedicated to the identification of the key parameters leading to plasmas with a better confined energy in order to guide the future experiments. For this purpose, a numerical code has been developed. It calculates the growth rates characterizing the instabilities onset. The stability analysis is completed by the evaluation of the shearing rate of the rotation due to the radial electric field. When this shearing rate is greater than the growth rate the ion turbulence is fully stabilised. The shearing rate and the growth rate are determined from the density, temperature and security factor profiles of a given plasma. Three types of plasmas have been analysed. In the Radiative Improved modes of TEXTOR, high charge number ions seeding lowers the growth rates. In Tore Supra-high density plasmas, a strong magnetic shear and/or a more efficient ion heating linked to a bifurcation of the toroidal rotation direction (which is not understood) trigger the improvement of the confinement. In other Tore Supra plasmas, locally steep electron pressure gradients have been obtained following magnetic shear reversal. This locally negative magnetic shear has a stabilizing effect. In these three families of plasmas, the growth rates decrease, the confinement improves, the density and temperature profiles are steeper. This steepening induces an increase of the rotation shearing rate, which then maintains the confinement high quality. (author)

  6. Erosion and deposition in tokamaks

    International Nuclear Information System (INIS)

    Staudenmaier, G.

    1985-01-01

    The flow of metal impurities from the wall and limiter to the plasma, and back towards the wall, is investigated using surface collection probes and subsequent surface analysis in order to understand impuritiy generation and impurity transport. Impurity fluxes and their scrapeoff lengths have been investigated for several years in a large number of tokamaks. The results are summarized and discussed. Erosion exceeding deposition was first observed to occur at limiterlike structures closest to the plasma edge. Recently, a new probe has been developed to measure quantitatively the erosion in ASDEX. Subsequent quantitative surface analysis is performed in situ by electron induced x-ray analysis. Erosion caused either by ions (limiter) or charge exchange neutrals (wall) can be investigated separately. The erosion at the wall is about two orders of magnitude smaller than the erosion at limiterlike structures, which is of the order of one monolayer per discharge. Simultaneous measurements of deposition and erosion have been performed to elucidate net values of deposition and erosion

  7. THE EFFECTS OF POSSIBLE CONTAMINATION ON THE RADIOCARBON DATING OF THE DEAD SEA SCROLLS II : EMPIRICAL METHODS TO REMOVE CASTOR OIL AND SUGGESTIONS FOR REDATING

    NARCIS (Netherlands)

    Rasmussen, Kaare Lund; van der Plicht, Johannes; Doudna, Gregory; Nielsen, Frederik; Hojrup, Peter; Stenby, Erling Halfdan; Pedersen, Carl Th; Højrup, Peter

    2009-01-01

    While kept at the Rockefeller Museum in East Jerusalem, many Dead Sea Scroll fragments were exposed to castor oil by the original team of editors in the course of cleaning the parchments. Castor oil must be regarded as a serious contaminant in relation to radiocarbon dating. If modern castor oil is

  8. Identification of diacylglycerol and triacylglycerols containing 11,12,13-trihydroxy-9,14-octadecadienoic acid in castor oil by mass spectrometry

    Science.gov (United States)

    Castor oil has many industrial uses. Molecular species of acylglycerols containing monohydroxy, dihydroxy and trihydroxy fatty acids in castor oil have been reported. The identification of acylglycerols containing a triOH18:2 fatty acid in castor oil is reported here. The structure of this novel fat...

  9. TRANSFORMATION OF RICINOLEIC OF CASTOR OIL INTO LINOLEIC (OMEGA-6 AND CONJUGATED LINOLEIC ACID BY DEHYDRATION

    Directory of Open Access Journals (Sweden)

    Marham Sitorus

    2010-06-01

    Full Text Available The ricinoleic of Castor Oil was dehydrated by various dehydrator agent (P2O5, K2CO3, H3PO4, NaHSO4, Al2O3, molecular sieve and activated bentonite at 450 °C - HCl on the same condition (150 °C, mol ratio 1:1 and 2 hours . The compositions of Refined Ricinus Castor Oil as starting material were : 0.92% palmitic , 5.56% linoleic , 4.07% octadecanoic , 1.22% stearic and 85.06% ricinoleic. The spesific wave number of IR was bandwith 3411 cm-1 caused of hydroxyl (-OH group of ricinoleic at C-12 as main component. The product was Dehydrated Castor Oil (DCO mixed of linoleic (omega 6 [C18 : 2 (9,12] and Conjugated Linoleic Acid (CLA [C18: 2 (9,11]. The best dehydrator was P2O5 based on three parameters were : Free Fatty Acid (FFA nearly the same (1.855% of Castor oil and 2.139% of DCO, the most increased of Iodium value (49.860 mg/g of Castor oil in to 63.090 mg/g of DCO, and the most decresed of hydroxyl number (28.27 mg of Castor oil in to 17.75 mg/g of DCO. To optimized the dehydration was done by various number of P2O5 (3g, 5g and 7g, tempereture (room, 100 °C and 150 °C and time (2h, 2.5h, 3h, and 3.5h. The optimal conditon of dehydration was not found yet. Some of sugestted or idea for dehydration were: dehydration must be done by base or netral, non oxydator dehydrator, mol ratio 1:1, temperature (100-150 °C and 2-3.5 h. Based on GC-MS the best DCO (7g P2O5, 150 °C and 3.5 h were showed that the decrease of ricinoleic 14.13% (85.08% of Castor Oil in to 70.93% of DCO, increased linoleic 2.09% (5.56 of Castor oil in to 7.65% of DCO and conducted of 9.09% CLA. Some new peaks between linoleic and ricinoleic are maybe isomer's of linoleic and CLA. The wave number of cunjugated alkene (C=C (1666.3 cm-1 of IR spectra of DCO together with GC-MS chromatogram's to indicated that linoleic and CLA were conducted.   Keywords: castor oil, risinoleic, dehydration, omega 6 dan CLA

  10. Activation analysis of the compact ignition tokamak

    International Nuclear Information System (INIS)

    Selcow, E.C.

    1986-01-01

    The US fusion program has completed the conceptual design of a compact tokamak device that achieves ignition. The high neutron wall loadings associated with this compact deuterium-tritium-burning device indicate that radiation-related issues may be significant considerations in the overall system design. Sufficient shielding will be requied for the radiation protection of both reactor components and occupational personnel. A close-in igloo shield has been designed around the periphery of the tokamak structure to permit personnel access into the test cell after shutdown and limit the total activation of the test cell components. This paper describes the conceptual design of the igloo shield system and discusses the major neutronic concerns related to the design of the Compact Ignition Tokamak

  11. Helicity content and tokamak applications of helicity

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1986-05-01

    Magnetic helicity is approximately conserved by the turbulence associated with resistive instabilities of plasmas. To generalize the application of the concept of helicity, the helicity content of an arbitrary bounded region of space will be defined. The definition has the virtues that both the helicity content and its time derivative have simple expressions in terms of the poloidal and toroidal magnetic fluxes, the average toroidal loop voltage and the electric potential on the bounding surface, and the volume integral of E-B. The application of the helicity concept to tokamak plasmas is illustrated by a discussion of so-called MHD current drive, an example of a stable tokamak q profile with q less than one in the center, and a discussion of the possibility of a natural steady-state tokamak due to the bootstrap current coupling to tearing instabilities

  12. Effect of impurity radiation on tokamak equilibrium

    International Nuclear Information System (INIS)

    Rebut, P.H.; Green, B.J.

    1977-01-01

    The energy loss from a tokamak plasma due to the radiation from impurities is of great importance in the overall energy balance. Taking the temperature dependence of this loss for two impurities characteristic of those present in existing tokamak plasmas, the condition for radial power balance is derived. For the impurities considered (oxygen and iron) it is found that the radiation losses are concentrated in a thin outer layer of the plasma and the equilibrium condition places an upper limit on the plasma paraticle number density in this region. This limiting density scales with mean current density in the same manner as is experimentally observed for the peak number density of tokamak plasmas. The stability of such equilibria is also discussed. (author)

  13. Time - resolved thermography at Tokamak T-10

    International Nuclear Information System (INIS)

    Grunow, C.; Guenther, K.; Lingertat, J.; Chicherov, V.M.; Evstigneev, S.A.; Zvonkov, S.N.

    1987-01-01

    Thermographic experiments were performed at T-10 tokamak to investigate the thermic coupling of plasma and the limiter. The limiter is an internal equipment of the vacuum vessel of tokamak-type fusion devices and the interaction of plasma with limiter results a high thermal load of limiter for short time. In according to improve the limiter design the temperature distribution on the limiter surface was measured by a time-resolved thermographic method. Typical isotherms and temperature increment curves are presented. This measurement can be used as a systematic plasma diagnostic method because the limiter is installed in the tokamak whereas special additional probes often disturb the plasma discharge. (D.Gy.) 3 refs.; 7 figs

  14. Bowel Preparation of Outpatients for Intravenous Urography: Efficacy of Castor Oil Versus Bisacodyl

    Directory of Open Access Journals (Sweden)

    Huei-Chen Yang

    2005-04-01

    Full Text Available The purpose of this study was to compare the efficacy of two laxatives, castor oil and bisacodyl, in the routine bowel preparation of outpatients for intravenous urography (IVU. We used castor oil in patients undergoing IVU for 1 month, and then used bisacodyl in patients undergoing IVU for another month. Two uroradiologists, unaware of the method of bowel preparation, reviewed the standard radiographs and graded the residue in the large bowel and the clearness of the opacified urinary collecting system. In total, 71 consecutive outpatients received castor oil, and 84 received bisacodyl. For the castor oil group, grades from the two uroradiologists did not differ in terms of fecal residue on plain abdominal images (p = 0.54, and visualization of the urinary system on the left (p = 0.36 and right sides (p = 0.63. Findings were similar for bisacodyl recipients (p = 0.11, 0.59, and 0.32, respectively. When the laxative effect of the two agents was compared, we found no difference in the grading of fecal residue on plain abdominal images (p = 0.14, or in visualization of the urinary system on the left (p = 0.31 and right sides (p = 0.98. In conclusion, we observed no difference in laxative efficacy between castor oil and bisacodyl; thus, bisacodyl may be a useful alternative for bowel preparation before IVU.

  15. Environmental effects of nanosilver: impact on castor seed germination, seedling growth, and plant physiology.

    Science.gov (United States)

    Yasur, Jyothsna; Rani, Pathipati Usha

    2013-12-01

    Increasing use of nanoparticles in daily products is of great concern today, especially when their positive and negative impact on environment is not known. Hence, in current research, we have studied the impact of silver nanoparticle (AgNPs) and silver nitrate (AgNO3) application on seed germination, root, and shoot length of castor bean, Ricinus communis L. plant. Silver nanoparticles had no significant effects on seedling growth even at higher concentration of 4,000 mg L(-1), while the silver in bulk form as AgNO3 applied on the castor bean seeds inhibited the seed germination. Silver uptake in seedlings of the castor seeds on treatment with both the forms of silver was confirmed through atomic absorption spectroscopy studies. The silver nanoparticle and silver nitrate application to castor seeds also caused an enhanced enzymatic activity of ROS enzymes and phenolic content in castor seedlings. High-performance liquid chromatography analysis of individual phenols indicated enhanced content of parahydroxy benzoic acid. These kinds of studies are of great interest in order to unveil the movement and accumulation of nanoparticles in plant tissues for assessing future applications in the field or laboratory.

  16. Castor oil as a natural alternative to labor induction: A retrospective descriptive study.

    Science.gov (United States)

    DeMaria, Andrea L; Sundstrom, Beth; Moxley, Grace E; Banks, Kendall; Bishop, Ashlan; Rathbun, Lesley

    2018-04-01

    To describe birthing outcomes among women who consumed castor oil cocktail as part of a freestanding birth center labor induction protocol. De-identified data from birth logs and electronic medical records were entered into SPSS Statistics 22.0 for analysis for all women who received the castor oil cocktail (n=323) to induce labor between January 2008 and May 2015 at a birth center in the United States. Descriptive statistics were analyzed for trends in safety and birthing outcomes. Of the women who utilized the castor oil cocktail to stimulate labor, 293 (90.7%) birthed vaginally at the birth center or hospital. The incidence of maternal adverse effects (e.g., nausea, vomiting, extreme diarrhea) was less than 7%, and adverse effects of any kind were reported in less than 15% of births. An independent sample t-test revealed that parous women were more likely to birth vaginally at the birth center after using the castor oil cocktail than their nulliparous counterparts (pcastor oil cocktail to induce labor were able to give birth vaginally with little to no maternal or fetal complications. Findings indicate further research is needed to compare the safety and effectiveness of natural labor induction methodologies, including castor oil, to commonly used labor induction techniques in a prospective study or clinical trial. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  17. CASTOR BEAN AND SUNFLOWER INTERCROPPING SYSTEMS IN ROW ARRANGEMENT: BIOLOGICAL EFFICIENCY

    Directory of Open Access Journals (Sweden)

    Ciro de Miranda Pinto

    2012-07-01

    Full Text Available An experiment field was carried in the agricultural seasons 2008, 2009 and 2010, with aim of studying the response of castorbean (Ricinus communis L. intercropping with sunflower (Helianthus annus L. in row arrangement in the dryland farming conditions. In addition, it was evaluated the biological efficiency of plants in intercropping systems.The design used in the experiment was randomized block with seven treatement and four replications. The treatments were represented by rows of castor oil (Ma and sunflower (Gi listed below: 1Ma:1Gi; 1Ma:2Gi; 1Ma:3Gi; 2Ma:2Gi; 2Ma:3Gi; castor and sunflower in the monoculture. The efficiency of intercropping was measured by LER, ATER, LEC, average between LER and ATER, SPI and CoR. The grain yield of castor bean and sunflower were reduced in intercropped row arrangements. The row arrangement 1Ma:2Gi showed the smallest reduction of average productivity of castor beans and sunflower in the evaluation period of the experiment. The castor bean was the dominant crop in relation to sunflower.

  18. Effectiveness of castor oil extract on Escherichia coli and its endotoxins in root canals.

    Science.gov (United States)

    Valera, Marcia Carneiro; Maekawa, Lilian Eiko; Chung, Adriana; de Oliveira, Luciane Dias; Carvalho, Claudio Antonio Talge; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2012-01-01

    This in vitro study sought to evaluate the effectiveness of castor oil extract used as an irrigating solution on Escherichia coli and its endotoxins in root canals. Sixty single-rooted teeth were prepared (using castor oil extract as irrigating solution) and divided into five groups (n = 12): Group 1 samples were treated with calcium hydroxide (Ca(OH)2), Group 2 samples were treated with polymyxin B, Group 3 samples were treated with Ca(OH)2 and 2% chlorhexidine gel (CHX), and Group 4 samples were treated with castor oil extract. A control group used physiological saline solution as an irrigant. Canal content samples were collected at four different times: immediately after instrumentation, seven days after instrumentation, after 14 days of intracanal medication, and seven days after removal of intracanal medication. A plating method was used to assess antimicrobial activity and the quantification of endotoxins was evaluated by the chromogenic Limulus lysate assay. Data were submitted to ANOVA and a Dunn test (a = 5%). Irrigation with castor oil extract decreased E. coli counts but had no effect on the level of endotoxins. Samples taken seven days after removal of medication revealed a significant reduction in endotoxin levels in Groups 3 and 4. Compared to the saline solution irrigation, castor oil extract decreased microorganism counts in root canals immediately after canal preparation. None of the medications used completely eliminated endotoxins in the root canal.

  19. Optimization of biodiesel production from castor oil using response surface methodology.

    Science.gov (United States)

    Jeong, Gwi-Taek; Park, Don-Hee

    2009-05-01

    The short supply of edible vegetable oils is the limiting factor in the progression of biodiesel technology; thus, in this study, we applied response surface methodology in order to optimize the reaction factors for biodiesel synthesis from inedible castor oil. Specifically, we evaluated the effects of multiple parameters and their reciprocal interactions using a five-level three-factor design. In a total of 20 individual experiments, we optimized the reaction temperature, oil-to-methanol molar ratio, and quantity of catalyst. Our model equation predicted that the following conditions would generate the maximum quantity of castor biodiesel (92 wt.%): a 40-min reaction at 35.5 degrees C, with an oil-to-methanol molar ratio of 1:8.24, and a catalyst concentration of 1.45% of KOH by weight of castor oil. Subsequent empirical analyses of the biodiesel generated under the predicted conditions showed that the model equation accurately predicted castor biodiesel yields within the tested ranges. The biodiesel produced from castor oil satisfied the relevant quality standards without regard to viscosity and cold filter plugging point.

  20. The castor oil production in Brazil and the biodiesel program (Probiodiesel); A producao de mamona no Brasil e o Probiodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Cezar Menezes; Almeida Neto, Jose Adolfo de; Pires, Monica de Moura [Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Grupo Bioenergia e Meio Ambiente]. E-mails: biocomb@uesc.br; Rocha, Pauletti Karllien [Secretaria de Ciencia, Tecnologia e Inovacao do Estado da Bahia (SECTI), Salvador, BA (Brazil)]. E-mail: pauletti@secti.ba.gov.br

    2004-07-01

    The objective of this work is to present a prospective study of the national production of biodiesel and castor oil and to determine the level of the public investment necessary to attain the proposed production. For replacement of 2% of the diesel internal consumption, 786 millions of liters of biodiesel will be necessary, based on the consumption of 2003. From this amount 293 millions of liters (40%) will be derived from the castor oil. Considering the castor oil agricultural productivity of 1.8 t/ha and the 45% industrial income in oil, it will be necessary the planting of 360.000 ha and investment amount of R$ 370 million. An idleness of 71% of the castor oil crushing industry has been detected, but this sector works with profit as function of castor oil price. An deficit of 55% between the castor oil planting area and the necessary one for biodiesel production was identified, considering that all the castor oil will be exclusively used for this purpose. With the proposed goals and without the necessary allocation of public resources for castor oil production, probably it will not be possible to expect that 1/5 of the biodiesel national production can come from the domestic agricultural planting.

  1. Evaluation of reaction mechanisms and the kinetic parameters for the transesterification of castor oil by liquid enzymes

    DEFF Research Database (Denmark)

    Andrade, Thalles Allan; Errico, Massimiliano; Christensen, Knud Villy

    2017-01-01

    of the transesterification of castor oil with methanol using the enzyme Eversa® Transform as catalyst were investigated. Reactions were carried out for 8 hours at 35 °C with: an alcohol-to-oil molar ratio equal to 6:1, a 5 wt% of liquid enzyme solution and addition of 5 wt% of water by weight of castor oil. From...

  2. A Fast Shutdown Technique for Large Tokamaks

    International Nuclear Information System (INIS)

    Fredrickson, E.; Schmidt, G.L.; Hill, K.; Jardin, S.C.

    1999-01-01

    A practical method is proposed for the fast shutdown of a large ignited tokamak. The method consists of injecting a rapid series of 30-50 deuterium pellets doped with a small ( 0.0005%) concentration of Krypton impurity, and simultaneously ramping the plasma current and shaping fields down over a period of several seconds using the poloidal field system. Detailed modeling with the Tokamak Simulation Code using a newly developed pellet mass deposition model shows that this method should terminate the discharge in a controlled and stable way without producing significant numbers of runaway electrons. A partial prototyping of this technique was accomplished in TFTR

  3. Tokamak power systems studies, FY 1985

    Energy Technology Data Exchange (ETDEWEB)

    Baker, C.C.; Brooks, J.N.; Ehst, D.A.; Smith, D.L.; Sze, D.K.

    1985-12-01

    The Tokamak Power System Studies (TPSS) at ANL in FY-1985 were devoted to exploring innovative design concepts which have the potential for making substantial improvements in the tokamak as a commercial power reactor. Major objectives of this work included improved reactor economics, improved environmental and safety features, and the exploration of a wide range of reactor plant outputs with emphasis on reduced plant sizes compared to STARFIRE. The activities concentrated on three areas: plasma engineering, impurity control, and blanket/first wall/shield technology. 205 refs., 125 figs., 107 tabs.

  4. Proposed tokamak poloidal field system development program

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.D.; Vogel, H.F.; Warren, R.W.; Weldon, D.M.

    1977-05-01

    A program is proposed to develop poloidal field components for TNS and EPR size tokamak devices and to test these components in realistic circuits. Emphasis is placed upon the development of the most difficult component, the superconducting ohmic-heating coil. Switches must also be developed for testing the coils, and this switching technology is to be extended to meet the requirements for the large scale tokamaks. Test facilities are discussed; power supplies, including a homopolar to drive the coils, are considered; and poloidal field systems studies are proposed.

  5. Periodic disruptions in the MT-1 tokamak

    International Nuclear Information System (INIS)

    Zoletnik, S.

    1988-11-01

    Disruptive instabilities are common phenomena in toroidal devices, especially in tokamaks. Three types can be distinguished: internal, minor and major disruptions. Periodic minor disruptions in the MT-1 tokamak were measured systematically with values of the limiter safety factor between 4 and 10. The density limit as a function of plasma current and horizontal displacement was investigated. Precursor oscillations always appear before the instability with increasing amplitude but can be observed at the density limit with quasi-stationary amplitude. Phase correlation between precursor oscillations were measured with Mirnov coils and x-ray detectors, and they show good agreement with a simple magnetic island model. (R.P.) 11 refs.; 6 figs

  6. Gas blanket fueling of a tokamak reactor

    International Nuclear Information System (INIS)

    Gralnick, S.L.

    1978-01-01

    The purpose of this paper is a speculative investigation of the potential of fueling a Tokamak by introducing a sufficiently large quantity of gaseous deuterium and tritium at the vacuum wall boundary. It is motivated by two factors: current generation tokamaks are, in a manner of speaking, fueled from the edge quite successfully as is evidenced by pulse lengths that are long compared to particle recycling times, and by rapid plasma density increase produced by gas puffing, alternative, deep penetration fueling techniques that have been proposed possess severe technological problems and large costs

  7. Thermonuclear ignition in the next generation tokamaks

    International Nuclear Information System (INIS)

    Johner, J.

    1989-04-01

    The extrapolation of experimental rules describing energy confinement and magnetohydrodynamic - stability limits, in known tokamaks, allow to show that stable thermonuclear ignition equilibria should exist in this configuration, if the product aB t x of the dimensions by a magnetic-field power is large enough. Quantitative application of this result to several next-generation tokamak projects show that those kinds of equilibria could exist in such devices, which would also have enough additional heating power to promote an effective accessible ignition

  8. Overview of spherical tokamak research in Japan

    Science.gov (United States)

    Takase, Y.; Ejiri, A.; Fujita, T.; Fukumoto, N.; Fukuyama, A.; Hanada, K.; Idei, H.; Nagata, M.; Ono, Y.; Tanaka, H.; Uchida, M.; Horiuchi, R.; Kamada, Y.; Kasahara, H.; Masuzaki, S.; Nagayama, Y.; Oishi, T.; Saito, K.; Takeiri, Y.; Tsuji-Iio, S.

    2017-10-01

    Nationally coordinated research on spherical tokamak is being conducted in Japan. Recent achievements include: (i) plasma current start-up and ramp-up without the use of the central solenoid by RF waves (in electron cyclotron and lower hybrid frequency ranges), (ii) plasma current start-up by AC Ohmic operation and by coaxial helicity injection, (iii) development of an advanced fuelling technique by compact toroid injection, (iv) ultra-long-pulse operation and particle control using a high temperature metal wall, (v) access to the ultra-high-β regime by high-power reconnection heating, and (vi) improvement of spherical tokamak plasma stability by externally applied helical field.

  9. Radial electric fields for improved tokamak performance

    International Nuclear Information System (INIS)

    Downum, W.B.

    1981-01-01

    The influence of externally-imposed radial electric fields on the fusion energy output, energy multiplication, and alpha-particle ash build-up in a TFTR-sized, fusing tokamak plasma is explored. In an idealized tokamak plasma, an externally-imposed radial electric field leads to plasma rotation, but no charge current flows across the magnetic fields. However, a realistically-low neutral density profile generates a non-zero cross-field conductivity and the species dependence of this conductivity allows the electric field to selectively alter radial particle transport

  10. Shielding and maintainability in an experimental tokamak

    International Nuclear Information System (INIS)

    Abdou, M.A.; Fuller, G.; Hager, E.R.; Vogelsang, W.F.

    1979-01-01

    This paper presents the results of an attempt to develop an understanding of the various factors involved. This work was performed as a part of the task assigned to one of the expert groups on the International Tokamak Reactor (INTOR). However, the results of this investigation are believed to be generally applicable to the broad class of the next generation of experimental tokamak facilities such as ETF. The shielding penalties for requiring personnel access are quantified. This is followed by a quantitative estimate of the benefits associated with personnel access. The penalties are compared to the benefits and conclusions and recommendations are developed on resolving the issue

  11. Tokamak Engineering Technology Facility scoping study

    Energy Technology Data Exchange (ETDEWEB)

    Stacey, W.M. Jr.; Abdou, M.A.; Bolta, C.C.

    1976-03-01

    A scoping study for a Tokamak Engineering Technology Facility (TETF) is presented. The TETF is a tokamak with R = 3 m and I/sub p/ = 1.4 MA based on the counterstreaming-ion torus mode of operation. The primary purpose of TETF is to demonstrate fusion technologies for the Experimental Power Reactor (EPR), but it will also serve as an engineering and radiation test facility. TETF has several technological systems (e.g., superconducting toroidal-field coil, tritium fuel cycle, impurity control, first wall) that are prototypical of EPR.

  12. Can better modelling improve tokamak control?

    International Nuclear Information System (INIS)

    Lister, J.B.; Vyas, P.; Ward, D.J.; Albanese, R.; Ambrosino, G.; Ariola, M.; Villone, F.; Coutlis, A.; Limebeer, D.J.N.; Wainwright, J.P.

    1997-01-01

    The control of present day tokamaks usually relies upon primitive modelling and TCV is used to illustrate this. A counter example is provided by the successful implementation of high order SISO controllers on COMPASS-D. Suitable models of tokamaks are required to exploit the potential of modern control techniques. A physics based MIMO model of TCV is presented and validated with experimental closed loop responses. A system identified open loop model is also presented. An enhanced controller based on these models is designed and the performance improvements discussed. (author) 5 figs., 9 refs

  13. Helicity injection experiment in the SINP tokamak

    International Nuclear Information System (INIS)

    Bhattacharyya, Krishnendu; Ray, Nihar Ranjan

    2000-01-01

    The current drive or sustainment in magnetized toroidal resistive plasmas can be though of as a 'balance' between helicity injection and dissipation. In the present work, the mechanisms of the 'balance' in the fluctuating magnetized resistive plasmas of the SINP tokamak, have been studied experimentally. The result shows that the oscillatory vertical magnetic field and oscillatory plasmas' velocity in a definite phase relationship causes the balancing effect between helicity injection and dissipation and thus sustainment of plasma current for a longer period of time has been observed in the resistive plasmas of the SINP tokamak. (author)

  14. Where and How Wolves (Canis lupus) Kill Beavers (Castor canadensis).

    Science.gov (United States)

    Gable, Thomas D; Windels, Steve K; Bruggink, John G; Homkes, Austin T

    2016-01-01

    Beavers (Castor canadensis) can be a significant prey item for wolves (Canis lupus) in boreal ecosystems due to their abundance and vulnerability on land. How wolves hunt beavers in these systems is largely unknown, however, because observing predation is challenging. We inferred how wolves hunt beavers by identifying kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. We identified 22 sites where wolves from 4 different packs killed beavers. We classified these kill sites into 8 categories based on the beaver-habitat type near which each kill occurred. Seasonal variation existed in types of kill sites as 7 of 12 (58%) kills in the spring occurred at sites below dams and on shorelines, and 8 of 10 (80%) kills in the fall occurred near feeding trails and canals. From these kill sites we deduced that the typical hunting strategy has 3 components: 1) waiting near areas of high beaver use (e.g., feeding trails) until a beaver comes near shore or ashore, 2) using vegetation, the dam, or other habitat features for concealment, and 3) immediately attacking the beaver, or ambushing the beaver by cutting off access to water. By identifying kill sites and inferring hunting behavior we have provided the most complete description available of how and where wolves hunt and kill beavers.

  15. The performance of the CASTOR calorimeter during LHC Run 2

    CERN Document Server

    van de Klundert, Merijn H F

    2016-01-01

    CASTOR is an electromagnetic and hadronic tungsten-quartz sampling Cerenkov calorimeter located at the Compact Muon Solenoid experiment at the Large Hadron Collider. The detector has pseudorapidity borders at -5.2 and -6.6. An overview is presented on the various aspects of CASTOR’s performance and their relations during LHC Run 2. The equalisation of CASTOR’s channels is performed using beam-halo muons. Thereafter, CASTOR’s pedestal spectrum is studied. It is shown that noise estimates which are extracted using a fit, give on average a 10% lower threshold than statistical estimates. Gain correction factors, which are needed for the intercalibration, are obtained using a statistical, in-situ applicable method. The results of this method are shown to be reasonably consistent with laboratory measurements. Penultimately the absolute calibration is discussed, with emphasis on the relation between the scale uncertainty and CASTOR’s alignment. It is shown that the alignment’s contribution to the systemati...

  16. Characterization of the North American beaver (Castor canadensis) papillomavirus genome.

    Science.gov (United States)

    Rogovskyy, Artem S; Chen, Zigui; Burk, Robert D; Bankhead, Troy

    2014-01-10

    The papillomaviruses comprise a large group of viruses that cause proliferations of the stratified squamous epithelium of skin and mucosa in a variety of animals. An earlier report identified a novel papillomavirus of the North American beaver, Castor canadensis (CcanPV1) that was associated with cutaneous exophytic lesions. In the current study, we determined the sequence of the complete 7435 basepair genome of CcanPV1. The genome contains an Upstream Regulatory Region located between the end of L1 and the start of E6, and seven canonical papillomavirus open reading frames encoding five early (E6, E7, E1, E2, and E4) and two late (L2 and L1) proteins. No E5 open reading frame was detected. Phylogenetic analysis of the CcanPV1 genome places the virus between the genera Kappapapillomavirus and Mupapillomavirus. Analyses of the papillomavirus genomes detected in different species of the order Rodentia indicate these viruses do not form a monophyletic clade. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Where and How Wolves (Canis lupus Kill Beavers (Castor canadensis.

    Directory of Open Access Journals (Sweden)

    Thomas D Gable

    Full Text Available Beavers (Castor canadensis can be a significant prey item for wolves (Canis lupus in boreal ecosystems due to their abundance and vulnerability on land. How wolves hunt beavers in these systems is largely unknown, however, because observing predation is challenging. We inferred how wolves hunt beavers by identifying kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. We identified 22 sites where wolves from 4 different packs killed beavers. We classified these kill sites into 8 categories based on the beaver-habitat type near which each kill occurred. Seasonal variation existed in types of kill sites as 7 of 12 (58% kills in the spring occurred at sites below dams and on shorelines, and 8 of 10 (80% kills in the fall occurred near feeding trails and canals. From these kill sites we deduced that the typical hunting strategy has 3 components: 1 waiting near areas of high beaver use (e.g., feeding trails until a beaver comes near shore or ashore, 2 using vegetation, the dam, or other habitat features for concealment, and 3 immediately attacking the beaver, or ambushing the beaver by cutting off access to water. By identifying kill sites and inferring hunting behavior we have provided the most complete description available of how and where wolves hunt and kill beavers.

  18. Morphology and viability of castor bean genotypes pollen grains

    Directory of Open Access Journals (Sweden)

    Maria Selma Alves Silva Diamantino

    2016-01-01

    Full Text Available The objective of this work was to characterize the morphology and viability of the pollen of 15 genotypes of castor bean (Ricinus communis L. and to generate information that can assist in the selection of highly promising male parents for future use in genetic improvement programs aimed at producing seeds for oil extraction. Acetolysis and scanning electron microscopy was used to characterize the morphology of the pollen. The viability of the pollen grains was estimated by in vitro germination and colorimetric analysis (acetocarmine 2% and 2, 3, 5-triphenyltetrazolium chloride 1%. For the in vitro germination, pollen grains were grown in 10 types of solidified culture medium consisting of different concentrations of sucrose, boric acid, calcium nitrate, magnesium sulfate and potassium nitrate. The pollen grains had the following characteristics: medium size, isopolar and subspheroidal shape, radial symmetry, circular ambit, 3-colporate, elongated endoapertures, tectate exine and granulated sexine. The acetocarmine dye overestimated pollen viability. The media M5 and M8 were the most efficient at promoting the germination of pollen grains. The studied genotypes had high levels of viability and can therefore be used as male parents in genetic improvement programs.

  19. Transesterification of Castor Oil Catalyzed by Liquid Enzymes

    DEFF Research Database (Denmark)

    Andrade, Thalles Allan; Errico, Massimiliano; Christensen, Knud Villy

    2017-01-01

    economy. Based on this, and considering its low influence with food production, castor oil was investigated as a potential feedstock. Compared to other vegetable oils, it has a higher polarity resulting in better system homogeneity during reaction. The enzyme tested as catalyst was Eversa Transform. Four...... main reaction parameters were investigated for the optimization of the reaction route: the temperature was varied from 35 to 45 °C, the water content between 0-10 wt%, the enzyme content in the range of 2-10 wt%, and the alcohol-to-oil molar ratio from 4.5 to 7.5. The Response Surface Methodology...... was used to determine the optimal reaction conditions to get a high biodiesel yield and a low free fatty acids concentration. The results obtained showed that at 35 °C, 5 wt% of enzymes, 5 wt% of water, and a 6.0 alcohol-to-oil molar ratio, the yield in biodiesel was about 94% with a content of free fatty...

  20. Identification of diacylglycerol and triacylglycerol containing 11,12,13-trihydroxy-9,14-octadecadienoic acid in castor oil.

    Science.gov (United States)

    Lin, Jiann-Tsyh; Chen, Grace Q

    2011-02-28

    Castor oil has many industrial uses. Molecular species of acylglycerols containing monohydroxy, dihydroxy and trihydroxy fatty acids in castor oil have been reported. We report here the identification of acylglycerols containing a triOH18:2 fatty acid in castor oil. The structure of this novel fatty acid was proposed as 11,12,13-trihydroxy-9,14-octadecadienoic acid by the mass spectrometry of the lithiated adducts of acylglycerols in the HPLC fractions of castor oil. The fragmentation pathways of the lithiated adduct of 11,12,13-trihydroxy-9,14-octadecadienoic acid were proposed. We also proposed the biosynthetic pathways of polyhydroxy fatty acids in castor. Published by Elsevier B.V.

  1. Development of Operation Scenario for Spherical Tokamak at SNU

    International Nuclear Information System (INIS)

    Sung, C. K.; Park, Y. S.; Lee, H. Y.; Kang, J.; Hwang, Y. S.

    2009-01-01

    Several concepts for nuclear fusion plant exist. In these concepts, tokamak is the most promising one to realize nuclear fusion plant. Though tokamak has leading concept, and this has world record in fusion heating power, tokamak has the critical drawback: low heating efficiency. That is the reason why we need another alternative concept which compensates tokamak's disadvantage. Spherical Torus(ST) is one of these kinds of concepts. ST is a kind of tokamak which has low aspect ratio. This feature gives ST advantages compared to conventional tokamak: high efficiency, compactness, low cost. However, ST lacks central region for solenoid that is needed to start-up and sustain. Since it is the most efficient that initializing and sustaining by using solenoid, this is ST's intrinsic limitation. To overcome this, a new device which can start-up and sustain ST plasmas by means of continuous tokamak plasma injection has been designed

  2. Dynamics of the nearby multiple stellar systems. The Castor system (ADS 6175)

    International Nuclear Information System (INIS)

    Anosova, Zh.P.; Orlov, V.V.; Chernyshev, M.V.

    1989-01-01

    Statistical analysis of the astrometrical and astrophysical data for the components of the multiple stellar system Castor (ADS 6175) was used to determined the probability of physical connection among components and the dynamical state of this system. The uncertainties of the observational data are taken into account. It is shown that in this visual triple star system the components have a certain gravitational and dynamical connection. The relative orbit of close components AB is elliptical. The probability that the motion of the distant star C in relation to the centre of mass AB is elliptical and the Castor system is stable is 40.7%. The probability that the orbit of C is hyperbolic is 59.1%. The probability that the Castor system may be unstable non-hierarchical is 0.2%

  3. Thermophysical properties of biodiesel and related systems: (Liquid + liquid) equilibrium data for castor oil biodiesel

    International Nuclear Information System (INIS)

    Mazutti, Marcio A.; Voll, Fernando A.P.; Cardozo-Filho, Lúcio; Corazza, Marcos L.; Lanza, Marcelo; Priamo, Wagner L.; Oliveira, J. Vladimir

    2013-01-01

    Highlights: ► (Liquid + liquid) equilibrium data for multicomponent castor oil FAME and FAEE castor oil. ► Tie-lines and solubility curves (binodal) by cloud-point method for FAME and FAEE systems. ► Experimental data correlated using the UNIQUAC model. -- Abstract: This work reports new liquid–liquid solubility values (binodal curves) as well as (liquid + liquid) equilibrium data for, ternary and quaternary systems containing fatty acid methyl esters (FAME) and fatty acid ethyl esters (FAEE) from castor oil, water, glycerol, methanol and anhydrous ethanol at T = (303.15, 318.15, and 333.15) K. Solubility curves (binodal) were also obtained by the cloud-point method for binary systems containing FAME, FAEE, water, or glycerol. All results obtained can be considered of good quality. The experimental values were correlated using the UNIQUAC model, whose results presented good performance and satisfactory fitting of equilibrium values

  4. Study on Emission and Performance of Diesel Engine Using Castor Biodiesel

    Directory of Open Access Journals (Sweden)

    Md. Saiful Islam

    2014-01-01

    performance of diesel engine using the castor biodiesel and its blend with diesel from 0% to 40% by volume. The acid-based catalyzed transesterification system was used to produce castor biodiesel and the highest yield of 82.5% was obtained under the optimized condition. The FTIR spectrum of castor biodiesel indicates the presence of C=O and C–O functional groups, which is due to the ester compound in biodiesel. The smoke emission test revealed that B40 (biodiesel blend with 40% biodiesel and 60% diesel had the least black smoke compared to the conventional diesel. Diesel engine performance test indicated that the specific fuel consumption of biodiesel blend was increased sufficiently when the blending ratio was optimized. Thus, the reduction in exhaust emissions and reduction in brake-specific fuel consumption made the blends of caster seed oil (B20 a suitable alternative fuel for diesel and could help in controlling air pollution.

  5. Castor oil biodiesel: an economic evaluation; Biodiesel de mamona: uma avaliacao economica

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Monica de Moura; Alves, Jaenes Miranda; Almeida Neto, Jose Adolfo de; Almeida, Cezar Menezes; Sousa, Geovania Silva de; Cruz, Rosenira Serpa da; Monteiro, Renata; Lopes, Beatriz Sampaio; Robra, Sabine [Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Grupo Bioenergia e Meio Ambiente]. E-mails: mpires@uesc.br; jaenes@uesc.br; jalmeida@uesc.br; roserpa@uesc.br

    2004-07-01

    The production cost of castor oil biodiesel by methyl way and its economic viability, using as reference the production cost data of castor oil and the implantation of the pilot plant at UESC - state university of Santa Cruz, Bahia State, Brazil was determined. From this information, it was seen that the estimated price of castor oil biodiesel is close to the diesel price in the Itabuna market, Bahia state, Brazil. The indicators show economic viability of the mini-power plant installation. Such information are preliminary estimative for the market and can be modified as function of changes in the main factors used to have the production costs, as well as the sectorial policies that drives the activity as much in levels of raw material production as in biodiesel.

  6. Tokamak startup: problems and scenarios related to the transient phases of ignited tokamak operations

    International Nuclear Information System (INIS)

    Sheffield, J.

    1985-01-01

    During recent years improvements have been made to tokamak startup procedures, which are important to the optimization of ignited tokamaks. The use of rf-assisted startup and noninductive current drive has led to substantial reduction and even complete elimination of the volt-seconds used during startup, relaxing constraints on poloidal coil, vacuum vessel, and structure design. This paper reviews these and other improvements and discusses the various bulk heating techniques that may be used to ignite a D-T plasma

  7. A need for non-tokamak approaches to magnetic fusion energy

    International Nuclear Information System (INIS)

    Bathke, C.G.; Krakowski, R.A.; Miller, R.L.

    1992-01-01

    Focusing exclusively on conventional tokamak physics in the quest for commercial fusion power is premature, and the options for both advanced-tokamak and non-tokamak concepts need continued investigation. The basis for this claim is developed, and promising advanced-tokamak and non-tokamak options are suggested

  8. Antibacterial effects of castor oil on foodborne pathogens: comparative evaluation of the components

    Directory of Open Access Journals (Sweden)

    samaneh hatami

    2016-01-01

    Full Text Available For centuries, antimicrobial compounds derived from plants, have been used for medicinal treatment. The aim of this study was to evaluate the antibacterial activity of castor seed oil extracted from Mashhad and Isfahan varieties on Staphylococcus aureus, Escherichia coli and Listeria inocula. The sensitivity of the indicator bacteria was evaluated using disc diffusion technique and minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC were tested by broth micro-dilution assays. Oil from castor seeds was extract by Soxhlet method and the extracted oils were analyzed by a gas chromatograph connected to a mass spectrometer (GC/MS. According to the results of various dilutions of the extracts, MIC for castor oils ranged 12.5-25%, except for the Isfahan variety that was estimated at 6.25-12.5% for E. coli. The two varieties of castor oils showed the MBC activity on the indicator organisms at the original (100% concentration. Based on GC/MS data, ricinoleic acid (1.307%, genetistic acid (0.597% and palmitic acid (1.947% were detected in oil extracted from Isfahan variety; meanwhile these compounds did not found in Mashhad variety. According to the results, the two castor varieties had antibacterial impact on E. coli. In addition, the overall antimicrobial activity of Isfahan variety was higher than Mashhad type. It seems that the presence of phenolic compounds as well as camphoric and unsaturated fatty acids is the major reason for the higher antibacterial effect of Isfahan variety on E. coli. Considering the inhibitory impact of castor oil, it can be used as a natural preservative in food industry.

  9. Castor oil for induction of labor in post-date pregnancies: A randomized controlled trial.

    Science.gov (United States)

    Gilad, Ronit; Hochner, Hagit; Savitsky, Bella; Porat, Shay; Hochner-Celnikier, Drorith

    2018-02-01

    Castor oil is a substance used for labor induction in an inpatient setting. However, its efficacy as an agent for the induction of labor, for post-date pregnancies in an outpatient setup is unknown. Efficacy of castor oil as an agent for the induction of labor, for post-date pregnancies in outpatient settings. Eighty-one women with a low-risk post-date singleton pregnancy with a Bishop score≤7, without effective uterine contractions were randomized to the intervention, 60ml of castor oil, or the control, 60ml of sun-flower oil. The primary outcome was proportion of women entering the active phase of labor 24, 36, 48h after ingestion. Secondary outcomes included meconium stained amniotic fluid, abnormal fetal heart rate tracing, cesarean section rate, instrumental deliveries, birth weight, 5min Apgar score, chorioamnionitis, hypertensive complications, retained placenta, and post-partum hemorrhage. Intervention and control groups included 38 and 43 women, respectively. No differences in baseline characteristics, except for age were noted. The observed interaction between castor oil and parity was significant (p interaction =0.02). Multiparous women in the intervention group exhibited a significant beneficial effect on entering active labor within 24, 36 and 48h after castor oil consumption compared with the placebo (Hazard Ratio=2.93, p=0.048; Hazard Ratio=3.29, p=0.026; Hazard Ratio=2.78, p=0.042 respectively). This effect was not noted among primiparous women. No differences in rate of obstetric complications or adverse neonatal outcomes were noted. Castor oil is effective for labor induction, in post-date multiparous women in outpatient settings. Copyright © 2017. Published by Elsevier Ltd.

  10. Design of the CMS-CASTOR subdetector readout system by reusing existing designs

    CERN Document Server

    Beaumont, W

    2009-01-01

    CASTOR is a cylindrical calorimeter with a length of 1.5m and a diameter of 60cm located at 14.3 meters from the CMS interaction point and covering the range in pseudorapidity corresponding to 5.1 < | eta | < 6.6. The CASTOR project was approved in the middle of 2007. Given the limited resources and time, developing a readout system from scratch was excluded. Here the final implementations of the readout chain, the considerations for the different choices as well as the performance of the installed equipment are discussed.

  11. Design of the CMS-CASTOR sub detector readout system by reusing existing designs

    CERN Document Server

    Beaumont, Willem

    2009-01-01

    CASTOR is a cylindrical calorimeter with a length of 1.5m and a diameter of 60cm located at 14.3 meters from the CMS interaction point and covering the range in pseudo-rapidity corresponding to 5.1 ~\\textless~ \\textbar~ eta~ \\textbar ~ \\textless ~ 6.6. The CASTOR project was approved in the middle of 2007. Given the limited resources and time, developing a readout system from scratch was excluded. Here the final implementations of the readout chain, the considerations for the different choices as well as the performance of the installed equipment are discussed.

  12. Some Experiences with the Use of Castor Oil as a Dielectric.

    Science.gov (United States)

    1981-01-01

    Karl Fischer method. The first analysis was made after the oil vat had been in use for several weeks. The vat was covered with a polyethylene sheet but...parts by the oil, drying of the oil, and the determination of water in the two-phase sys- tem of castor oil in contact with mineral oil. Detailed...DRY CASTOR OIL The effect of moisture on the dielectric strength of organic liquids is well known2 .The dielectric strength of mineral oil, for example

  13. Reconstruction of the Cranial Vault Contour Using Tissue Expander and Castor Oil Prosthesis.

    Science.gov (United States)

    de Moraes, Sylvio Luiz Costa; Afonso, Alexandre Maurity de Paula; Santos, Roberto Gomes Dos; Mattos, Ricardo Pereira; Duarte, E Bruno Gomes

    2017-09-01

    Nowadays the reconstruction of craniofacial defects can be performed with different kinds of materials, which include the bone and the so-called biomaterials, which have the advantage of not needing a surgical site donor. Among these materials, great attention is given to polymers. In this large group, current attention is focused on the castor oil polymer, since this polymer is biocompatible, low cost, and has adequate strength for reconstruction of the craniomaxillofacial complex. This study aims to report the use of a prosthetic castor oil polymer for reconstruction of extensive defect, caused by a trauma, in the temporoparietal region.

  14. Preliminary measurements on Tokamak KT-5

    International Nuclear Information System (INIS)

    Wen Yizhi; Wan Shude; Rong Furui; Haan Shengshen; Liu Wandong; Liu Lei

    1987-01-01

    A small tokamak, KT-5, has been put in to operation since 1984. The major and minor radius of the plasma are 30 and 4.5 cm, respectively. The parameters obtained in the first phase of KT-5 experiments are as follows B t = 0.45 T, I p ≥ 5 kA, q(α) σ = 50 eV

  15. Fluctuation measurements with emissive probes in tokamaks

    Czech Academy of Sciences Publication Activity Database

    Adámek, Jiří; Ďuran, Ivan; Hron, Martin; Stöckel, Jan; Balan, P.; Schrittwieser, R.; Ionita, C.; Martines, E.; Tichý, M.; Van Oost, G.

    2002-01-01

    Roč. 52, č. 10 (2002), s. 1115-1120 ISSN 0011-4626. [Workshop Role of Electric Fields in Plasma Confinement and Exhaust/5th./. Montreux, 23.06.2002-24.06.2002] Institutional research plan: CEZ:AV0Z2043910 Keywords : tokamak, electron-emissive Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.311, year: 2002

  16. MHD stability of vertically asymmetric tokamak equilibria

    International Nuclear Information System (INIS)

    Dalhed, H.E.; Grimm, R.C.; Johnson, J.L.

    1981-03-01

    The ideal MHD stability properties of a special class of vertically asymmetric tokamak equilibria are examined. The calculations confirm that no major new physical effects are introduced and the modifications can be understood by conventional arguments. The results indicate that significant departures from up-down symmetry can be tolerated before the reduction in β becomes important for reactor operation

  17. Investigation of Tokamak Solid Divertor Target Options.

    Science.gov (United States)

    1981-05-26

    to fatigue nor is penetrated by sputtering. Norem and Bowers (47) report that a thickness of just 10 microns of beryllium should be sufficient to...Tokamak Surfaces", Journal of Nuclear Mater- ials, v.53, 1974, pp.107-110. 47. Norem , J. and D.A. Bowers, "Thin Low Z Coatings for Plasma Devices", ANL

  18. Supravodivý tokamak dobyl Asii

    Czech Academy of Sciences Publication Activity Database

    Řípa, Milan

    2006-01-01

    Roč. 54, č. 18 (2006), s. 58 ISSN 0040-1064 Institutional research plan: CEZ:AV0Z20430508 Keywords : superconducting tokamak * ITER * Tore Supra * Institute of Plasma Physics AV CR Subject RIV: BL - Plasma and Gas Discharge Physics

  19. Plasma-gun fueling for tokamak reactors

    International Nuclear Information System (INIS)

    Ehst, D.A.

    1980-11-01

    In light of the uncertain extrapolation of gas puffing for reactor fueling and certain limitations to pellet injection, the snowplow plasma gun has been studied as a fueling device. Based on current understanding of gun and plasma behavior a design is proposed, and its performance is predicted in a tokamak reactor environment

  20. Observations of arcing in the ISX tokamak

    International Nuclear Information System (INIS)

    Mioduszewski, P.; Clausing, R.E.; Heatherly, L.

    1979-01-01

    Arcing has been proposed as a major source of metal impurities in tokamak plasmas. Arc tracks have been observed in the ISX tokamak on the limiter, the inner-wall surface, and on the samples from the surface analysis station. Linear as well as fern-like arc tracks have been observed. From optical and SEM analysis of the tracks, it was estimated that about 10 16 to 10 17 atoms were released per arc. To study the influence of arcing on the tokamak discharge, an experiment was set up to measure electrical and optical signals of arcing in situ. In well controlled tokamak discharges, arcing was observed only during the initial breakdown of the plasma and during the quenching phase at the end of the discharge. In disrupted discharges, each plasma disruption was accompanied by arcing. The pulse-length of one single unipolar arc was measured to be about 50 μs and the current amplitude was typically about 20 A

  1. Microinstabilities in weak density gradient tokamak systems

    International Nuclear Information System (INIS)

    Tang, W.M.; Rewoldt, G.; Chen, L.

    1986-04-01

    A prominent characteristic of auxiliary-heated tokamak discharges which exhibit improved (''H-mode type'') confinement properties is that their density profiles tend to be much flatter over most of the plasma radius. Depsite this favorable trend, it is emphasized here that, even in the limit of zero density gradient, low-frequency microinstabilities can persist due to the nonzero temperature gradient

  2. Experimental methods to study tokamak plasma stability

    International Nuclear Information System (INIS)

    Perez-Navarro, A.

    1978-01-01

    Experimental devices to measure external instability modes with small pick-up coils to detect poloidal magnetic field fluctuations, and internal modes with soft-X-ray detectors are discussed. The characteristics of these devices are calculated for a small tokamak (R 0 = 30 cm, a = 10 cm, I 0 50 KA). (author)

  3. Tokamak Plasmas: Electron temperature $(T_ {e}) $ measurements ...

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 55; Issue 5-6. Tokamak Plasmas : Electron temperature ( T e ) measurements by Thomson scattering system. R Rajesh B Ramesh Kumar S K Varshney Manoj Kumar Chhaya Chavda Aruna Thakkar N C Patel Ajai Kumar Aditya Team. Contributed Papers Volume 55 ...

  4. [High beta tokamak research and plasma theory

    International Nuclear Information System (INIS)

    1990-01-01

    Our activities on High Beta Tokamak Research during the past 12 months of the present budget period can be divided into four areas: completion of kink mode studies in HBT; completion of carbon impurity transport studies in HBT; design of HBT-EP; and construction of HBT-EP. Each of these is described briefly in the sections of this progress report

  5. INTEGRATED PLASMA CONTROL FOR ADVANCED TOKAMAKS

    Energy Technology Data Exchange (ETDEWEB)

    HUMPHREYS,D.A; FERRON,J.R; JOHNSON,R.D; LEUER,J.A; PENAFLOR,B.G; WALKER,M.L; WELANDER,A.S; KHAYRUTDINOV,R.R; DOKOUKA,V; EDGELL,D.H; FRANSSON,C.M

    2003-10-01

    OAK-B135 Advanced tokamaks (AT) are distinguished from conventional tokamaks by their high degree of shaping, achievement of profiles optimized for high confinement and stability characteristics, and active stabilization of MHD instabilities to attain high values of normalized beta and confinement. These high performance fusion devices thus require accurate regulation of the plasma boundary, internal profiles, pumping, fueling, and heating, as well as simultaneous and well-coordinated MHD control action to stabilize such instabilities as tearing modes and resistive wall modes. Satisfying the simultaneous demands on control accuracy, reliability, and performance for all of these subsystems requires a high degree of integration in both design and operation of the plasma control system in an advanced tokamak. The present work describes the approach, benefits, and progress made in integrated plasma control with application examples drawn from the DIII-D tokamak. The approach includes construction of plasma and system response models, validation of models against operating experiments, design of integrated controllers which operate in concert with one another as well as with supervisory modules, simulation of control action against off-line and actual machine control platforms, and iteration of the design-test loop to optimize performance.

  6. Maintenance considerations of the STARFIRE commercial tokamak

    International Nuclear Information System (INIS)

    Trachsel, C.A.; Zahn, H.S.; Field, R.E.; Stevens, H.C.

    1979-01-01

    This paper presents the maintenance approach, the commercial tokamak design features that enhance maintenance and preliminary repair time and required mean-time-between-failures for major subsystems. Reactor hall building and maintenance equipment requirements including hot cells, coil rewinding, and cranes are discussed

  7. UCLA Tokamak Program Close Out Report.

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Robert John [UCLA/retired

    2014-02-04

    The results of UCLA experimental fusion program are summarized. Starting with smaller devices like Microtor, Macrotor, CCT and ending the research on the large (5 m) Electric Tokamak. CCT was the most diagnosed device for H-mode like physics and the effects of rotation induced radial fields. ICRF heating was also studied but plasma heating of University Type Tokamaks did not produce useful results due to plasma edge disturbances of the antennae. The Electric Tokamak produced better confinement in the seconds range. However, it presented very good particle confinement due to an "electric particle pinch". This effect prevented us from reaching a quasi steady state. This particle accumulation effect was numerically explained by Shaing's enhanced neoclassical theory. The PI believes that ITER will have a good energy confinement time but deleteriously large particle confinement time and it will disrupt on particle pinching at nominal average densities. The US fusion research program did not study particle transport effects due to its undue focus on the physics of energy confinement time. Energy confinement time is not an issue for energy producing tokamaks. Controlling the ash flow will be very expensive.

  8. Tokamak startup with electron cyclotron heating

    International Nuclear Information System (INIS)

    Holly, D.J.; Prager, S.C.; Shepard, D.A.; Sprott, J.C.

    1980-04-01

    Experiments are described in which the startup voltage in a tokamak is reduced by approx. 60% by the use of a modest amount of electron cyclotron resonance heating power for preionization. A 50% reduction in volt-second requirement and impurity reflux are also observed

  9. Tokamak startup with electron cyclotron heating

    Energy Technology Data Exchange (ETDEWEB)

    Holly, D J; Prager, S C; Shepard, D A; Sprott, J C

    1980-04-01

    Experiments are described in which the startup voltage in a tokamak is reduced by approx. 60% by the use of a modest amount of electron cyclotron resonance heating power for preionization. A 50% reduction in volt-second requirement and impurity reflux are also observed.

  10. Runaway electrons in the SINP tokamak

    Indian Academy of Sciences (India)

    The highly energised runaway electrons (П 100 keV) is practically inevitable in the presence of an electric field. In tokamak discharges, these, on one hand, are a source of concern causing damages to the limiter and torus walls [1] whereas, on the other hand, it can be used as a diagnostic tool to determine the properties of ...

  11. The ARIES tokamak fusion reactor study

    International Nuclear Information System (INIS)

    Bartlit, J.R.; Bathke, C.G.; Krakowski, R.A.; Miller, R.L.; Beecraft, W.R.; Hogan, J.T.; Peng, Y.K.M.; Reid, R.L.; Strickler, D.J.; Whitson, J.C.; Blanchard, J.P.; Emmert, G.A.; Santarius, J.F.; Sviatoslavsky, I.N.; Wittenberg, L.J.

    1989-01-01

    The ARIES study is a community effort to develop several visions of the tokamak as fusion power reactors. The aims are to determine their potential economics, safety, and environmental features and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Three ARIES visions are planned, each having a different degree of extrapolation from the present data base in physics and technology. The ARIES-I design assumes a minimum extrapolation from current tokamak physics (e.g., 1st stability) and incorporates technological advances that can be available in the next 20 to 30 years. ARIES-II is a DT-burning tokamak in 2nd stability regime and employs both potential advances in the physics and expected advances in technology and engineering; and ARIES-III is a conceptual D 3 He reactor. This paper focuses on the ARIES-I design. Parametric systems studies show that the optimum 1st stability tokamak has relatively low plasma current (∼ 12 MA), high plasma aspect ratio (∼ 4-6), and high magnetic field (∼ 24 T at the coil). ARIES-I is 1,000 MWe (net) reactor with a plasma major radius of 6.5 m, a minor radius of 1.4 m, a neutron wall loading of about 2.8 MW/m 2 , and a mass power density of about 90 kWe/ton. The ARIES-I reactor operates at steady state using ICRF fast waves to drive current in the plasma core and lower-hybrid waves for edge-plasma current drive. The current-drive system supplements a significant (∼ 57%) bootstrap current contribution. The impurity control system is based on high-recycling poloidal divertors. Because of the high field and large Lorentz forces in the toroidal-field magnets, innovative approaches with high-strength materials and support structures are used. 24 refs., 4 figs., 1 tab

  12. Plea for stellarator funding raps tokamaks

    International Nuclear Information System (INIS)

    Blake, M.

    1992-01-01

    The funding crunch in magnetic confinement fusion development has moved the editor of a largely technical publication to speak out on a policy issue. James A. Rome, who edits Stellarator News from the Fusion Energy Division at Oak Ridge National Laboratory, wrote an editorial that appeared on the front page of the May 1992 issue. It was titled open-quotes The US Stellarator Program: A Time for Renewal,close quotes and while it focused chiefly on that subject (and lamented the lack of funding for the operation of the existing ATF stellarator at Oak Ridge), it also cited some of the problems inherent in the mainline MCF approach--the tokamak--and stated that if the money can be found for further tokamak design upgrades, it should also be found for stellarators. Rome wrote, open-quotes There is growing recognition in the US, and elsewhere, that the conventional tokamak does not extrapolate to a commercially competitive energy source except with very high field coils ( 1000 MWe).close quotes He pointed up open-quotes the difficulty of simultaneously satisfying conflicting tokamak requirements for efficient current drive, high bootstrap-current fraction, complete avoidance of disruptions, adequate beta limits, and edge-plasma properties compatible with improved (H-mode) confinement and acceptable erosion of divertor plates.close quotes He then called for support for the stellarator as open-quotes the only concept that has performance comparable to that achieved in tokamaks without the plasma-current-related limitations listed above.close quotes

  13. Production of bran castor biochar through slow pyrolysis

    Science.gov (United States)

    Pissinati de Rezende, E. I.; Mangrich, A. S.; Batista, M. G. F.; Toledo, J. M. S.; Novotny, E. H.

    2012-04-01

    Pyrolysis is a thermal process of great importance in the present context, since it constitutes a significant alternative to adequate use of organic waste. The principal products obtained in the pyrolysis of discarded biomass are bio-oil, biogas and biochar. Biochar, in turn, may play a relevant role when applied to the soil to sequester carbon and as a soil conditioner, a material comparable to organic matter of Indians Black Earths from the Amazon Region [1]. Seeking to determine the best methods of preparation of biochar, we studied the pyrolysis of bran castor residue of the Brazilian biodiesel industry. Eight samples, from FM1 to FM8, were prepared in a factorial design 23 using two temperature (300 and 350 °C), two heating velocity (5 and 10 °C min-1) and two period of heating (30 and 60 min). The eight samples were studied using the spectroscopy: EPR, FTIR, RMN, XPS, and elemental analysis. By elemental analysis, the samples that keep for lower temperature of pyrolysis, 300 °C, showed H/C and N/C ratios greater than the samples of 350 °C. That higher value can be attributed to chemical structure more aliphatic than aromatic mainly in the FM7 sample (V = 10 °C min-1, T = 300 °C, P = 30 min). The greater N/C ratio correlated with a superior amount of nitrogenous functions, presenting by both FM7 and FM4 samples, as determined by 13C NMR spectroscopy with absorptions in 175 ppm (amide) and 55 ppm (N-alkyl).

  14. [Patterns of morphological variability in reintroduced populations with two beaver subspecies Castor fiber orientoeuropaeus and Castor fiber belorussicus (Castoridae, Rodentia) as an example].

    Science.gov (United States)

    Korablev, N P; Korablev, P N

    2012-01-01

    Taking as an example two beaver subspecies (Castor fiber orientoeuropaeus and Castor fiber belorussicus) with documented history of population formation, the patterns of morphological variability in translocated groups of mammals are studied. The variability of quantitative and qualitative traits in the formed populations is not characterized by a single direction. The main trend consists in increasing of adaptive norms diversity as related to body size. There observed a slight increase in the level of fluctuating asymmetry, reduction in polymorphism of nonmetric traits, and increase in fraction of rare aberrations. All these may be caused by inbreeding taking place during the period of prapopulations formation. The results of the study allow for considering the intraspecific differentiation as a consequence of adaptive variability (adaptatiogenesis) or subspecies hybridization. As for stochastic processes (genetic drift, founder effect), they seem to not influence the morphological variability significantly. The differences between discrete and dimensional traits are indicative of population groups' peculiarity.

  15. Development of nine new microsatellite loci for the American beaver, Castor canadensis (Rodentia: Castoridae), and cross-species amplification in the European beaver, Castor fiber.

    Science.gov (United States)

    Pelz-Serrano, Karla; Munguia-Vega, Adrian; Piaggio, Antoinette J; Neubaum, Melissa; Munclinger, Pavel; Pártl, Adam; VAN Riper Iii, Charles; Culver, Melanie

    2009-03-01

    We developed nine new nuclear dinucleotide microsatellite loci for Castor canadensis. All loci were polymorphic, except for one. The number of alleles ranged from two to four and from five to 12 in populations from Arizona and Wisconsin, respectively. Average heterozygosity ranged from 0.13 to 0.86 per locus. Since cross-species amplification in Castor fiber was successful only in four loci, we tested also nine recently published C. canadensis loci in the Eurasian species. Eight of the published loci amplified; however, three were monomorphic. The number of alleles was lower in C. fiber than in C. canadensis at all loci tested. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.

  16. An analysis of expressed sequence tags of developing castor endosperm using a full-length cDNA library

    Directory of Open Access Journals (Sweden)

    Wallis James G

    2007-07-01

    Full Text Available Abstract Background Castor seeds are a major source for ricinoleate, an important industrial raw material. Genomics studies of castor plant will provide critical information for understanding seed metabolism, for effectively engineering ricinoleate production in transgenic oilseeds, or for genetically improving castor plants by eliminating toxic and allergic proteins in seeds. Results Full-length cDNAs are useful resources in annotating genes and in providing functional analysis of genes and their products. We constructed a full-length cDNA library from developing castor endosperm, and obtained 4,720 ESTs from 5'-ends of the cDNA clones representing 1,908 unique sequences. The most abundant transcripts are genes encoding storage proteins, ricin, agglutinin and oleosins. Several other sequences are also very numerous, including two acidic triacylglycerol lipases, and the oleate hydroxylase (FAH12 gene that is responsible for ricinoleate biosynthesis. The role(s of the lipases in developing castor seeds are not clear, and co-expressing of a lipase and the FAH12 did not result in significant changes in hydroxy fatty acid accumulation in transgenic Arabidopsis seeds. Only one oleate desaturase (FAD2 gene was identified in our cDNA sequences. Sequence and functional analyses of the castor FAD2 were carried out since it had not been characterized previously. Overexpression of castor FAD2 in a FAH12-expressing Arabidopsis line resulted in decreased accumulation of hydroxy fatty acids in transgenic seeds. Conclusion Our results suggest that transcriptional regulation of FAD2 and FAH12 genes maybe one of the mechanisms that contribute to a high level of ricinoleate accumulation in castor endosperm. The full-length cDNA library will be used to search for additional genes that affect ricinoleate accumulation in seed oils. Our EST sequences will also be useful to annotate the castor genome, which whole sequence is being generated by shotgun sequencing at

  17. Organic matter and soil water content influence on BRS 188 castor bean growth

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, Rogerio Dantas de; Araujo, Ester Luiz de; Nascimento, Elka Costa Santos; Barros Junior, Genival [Universidade Federal de Campina Grande (UFCG), PB (Brazil); Guerra, Hugo O. Carvallo; Chaves, Lucia Helena G. [Universidade Federal de Campina Grande (UAEAg/UFCG), PB (Brazil). Unidade Academica de Engenharia Agricola

    2008-07-01

    The castor bean culture has been highlighted due to the several applications of its oil, which constitutes one of the best row materials for biodiesel manufacturing, and the base for several other industrial products. The objective of the present work was to study the effect of different soil water and soil organic matter on the castor bean growth. The experiment was conducted from April to August 2006 under greenhouse conditions using a randomized block 2x4 factorial design with two soil organic mater content (5.0 g.kg{sup -1} e 25.0 g.kg{sup -1}), four levels of available water (100, 90, 80 e 70% ) and three replicates. For this, 24 plastic containers, 75 kg capacity, were used on which was grown one plant 120 days after the seedling. At regular intervals the plant height was measured and the results analyzed statistically. For the qualitative treatments (with and without organic matter) the treatment means were compared through the Tukey test. For the quantitative ones (water levels) were used regressions. The castor bean cultivar height was significantly influenced by the organic matter content only after 80 days. Castor bean height increased significantly with the soil water content after 40 days of growing. (author)

  18. Evaluation of the use of Ogiri from castor oil seed as bait in trapping ...

    African Journals Online (AJOL)

    Pitfall traps were used to study insect fauna in a fallow plot at Nnamdi Azikiwe University Temporary site, Awka. The study was carried out for a period of seven weeks in the months of June and July 2013. The pitfall traps were baited using ogiri made from castor oil seed. The pitfall traps were used to investigate the activities ...

  19. Red fox, Vulpes vulpes, kills a European beaver, Castor fiber, kit

    OpenAIRE

    Kile, Nils B.; Nakken, Petter J.; Rosell, Frank; Espeland, Sigurd

    1996-01-01

    We observed an adult Red Fox (Vulpes vulpes) attack, kill and partially consume a 2-month-old female kit European Beaver (Castor fiber) near its lodge in Norway. The inner organs were consumed first. One adult beaver apparently attempted to frighten the fox away by tail-slapping.

  20. Undecylenic acid: a valuable and physiologically active renewable building block from castor oil.

    Science.gov (United States)

    Van der Steen, Marijke; Stevens, Christian V

    2009-01-01

    A lot of attention is currently being paid to the transition to a biobased economy. In this movement, most efforts concentrate on the development of bioenergy applications including bioethanol, biodiesel, thermochemical conversion of biomass, and others. However, in the energy sector other nonbiomass alternatives are known, whereas no valuable alternatives are available when thinking about chemical building blocks. Therefore, it is also essential to develop new routes for the synthesis of bio-based chemicals and materials derived thereof. Such intermediates can originate either from plants or from animals. Castor oil is a non-edible oil extracted from the seeds of the castor bean plant Ricinus communis (Euphorbiaceae), which grows in tropical and subtropical areas. Globally, around one million tons of castor seeds are produced every year, the leading producing areas being India, PR China, and Brazil.2 10-Undecenoic acid or undecylenic acid is a fatty acid derived from castor oil that, owing to its bifunctional nature, has many possibilities to develop sustainable applications.

  1. Impact of castor meal on root-knot and free-living nematodes

    Directory of Open Access Journals (Sweden)

    Cecilia Helena Silvino Prata Ritzinger

    2014-08-01

    Full Text Available Soil amendment may enhance soil quality as well as reduce plant-parasitic nematode. Despite the many applications already undertaken using castor meal, its efficiency in controlling root-knot nematodes (RKN, Meloidogyne incognita when applied to melon (Cucumis melo is still not clear. Three different amounts of castor meal (Ricinus communis applied were evaluated in microplots planted with melon either with or without RKN. The impact of castor meal on soil free-living nematode communities was also determined. Total nematode genera richness was estimated as 37 for the entire set of microplots sampled across both sampling dates. Rarefaction analysis resulted in 12 collector's curves out of the total of 30 that reached the horizontal asymptote. Univariate ANOVA with two factors yielded differences (p < 0.05 only with regard to the time factor. Simpson, Shannon, Evenness and Equitability indices showed a trend toward moderate increases by the end of the experiment, while the other indices were higher for tomato in pre-transplant sampling compared to harvest. Nematode community and diversity changed during the course of the experiment, although there was substantial confounding heterogeneity within and between the factorial combinations from the beginning. Root knot population was not reduced by the castor meal but increased throughout the period, regardless of treatment. RKN reduced melon yield, number and weight of melon.

  2. Salinity and cationic nature of irrigation water on castor bean cultivation

    Directory of Open Access Journals (Sweden)

    Geovani S. de Lima

    Full Text Available ABSTRACT This study aimed to evaluate the water relations, cell damage percentage and growth of the castor bean cv. ‘BRS Energia’ as a function of salinity and cationic nature of the water used in irrigation. The experiment was conducted in drainage lysimeters under greenhouse conditions in eutrophic Grey Argisol of sandy loam texture. Six combinations of water salinity and cations were studied (S1 - Control; S2 - Na+, S3 - Ca2+, S4 - Na+ + Ca2+; S5 - K+ and S6 - Na+ + Ca2+ + Mg2+, in a randomized block design with four replicates. In the control (S1, plants were irrigated with 0.6 dS m-1 water, whereas the other treatments received 4.5 dS m-1 water, obtained by adding different salts, all in the chloride form. Higher relative water content in the leaf blade of plants irrigated with K+-salinized water associated with leaf succulence are indicative of tolerance of the castor bean cv. ‘BRS Energia’ to salinity. Saline stress negatively affected castor bean growth, regardless of cationic nature of water. Among the ions studied, ‘BRS Energia’ castor bean was more sensitive to the presence of sodium in the irrigation water, in terms of both water relations and leaf succulence.

  3. Comeback of the beaver Castor fiber: An overview of old and new conservation problems

    NARCIS (Netherlands)

    Nolet, B.A.; Rosell, F.

    1998-01-01

    Due to over-hunting c. 1200 Eurasian beavers Castor fiber survived in eight relict populations in Europe and Asia at the beginning of the 20th century. Following hunting restrictions and translocation programmes in IS countries, the Eurasian beaver became re-established over much of its former

  4. Development and viability of a translocated beaver Castor fiber population in the Netherlands

    NARCIS (Netherlands)

    Nolet, B.A.; Baveco, J.M.

    1996-01-01

    We monitored survival, reproduction and emigration of a translocated beaver Castor fiber population in the Netherlands for five years and used a stochastic model to assess its viability. Between 1988 and 1991, 42 beavers were released in the Biesbosch National Park. The mortality was initially high

  5. Factors affecting scent-marking behaviour in Eurasion beaver (Castor fiber)

    NARCIS (Netherlands)

    Rosell, F.; Nolet, B.A.

    1997-01-01

    We tested the hypothesis that a main function of territory marking in Eurasian beaver (Castor fiber) is defense of the territory. The results showed that: (1) beaver colonies with close neighbors scent-mark more often than isolated ones; (2) the number of scent markings increased significantly with

  6. Lipase catalyzed transesterification of castor oil by straight chain higher alcohols.

    Science.gov (United States)

    Malhotra, Deepika; Mukherjee, Joyeeta; Gupta, Munishwar N

    2015-03-01

    Biolubricants from Castor oil were produced enzymatically by transesterification with higher alcohols using a lipase mixture of immobilized Mucor miehei (RMIM) and immobilized Candida antarctica lipase B (Novozym 435) under low water conditions. The conversions were in the range of 80-95% under the optimized conditions. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. Derivatization of castor oil based estolide esters: Preparation of epoxides and cyclic carbonates

    Science.gov (United States)

    Estolides that are based on castor oil and oleic acid are versatile starting points for the production of industrial fluids with new properties. A variety of unsaturated estolides were derivatized by epoxidation with hydrogen peroxide. The epoxidized estolides were further modified using supercritic...

  8. Evaluation of castor oil-based polyurethane membranes in rat bone-marrow cell culture.

    Science.gov (United States)

    Cerejo, Sofia de Amorim; Rahal, Sheila Canevese; Lima Neto, João Ferreira de; Voorwald, Fabiana Azevedo; Alvarenga, Fernanda da Cruz Landim e

    2011-10-01

    To evaluate three methods to isolate rats MSCs and to analyze the potential of a castor oil polyurethane base membrane as a scaffold for MSCs. Four male Wistar rats, aged 20-30 days were used. Bone marrow aspirates from femur and tibia were harvested using DMEM high glucose and heparin. The cell culture was performed in three different ways: direct culture and two types of density gradients. After 15 days, was made the 1st passage and analyzed cell viability with markers Hoerscht 33342 and propidium iodide. The MSCs were characterized by surface markers with the aid of flow cytometry. After this, three types of castor oil polyurethane membranes associated with the MSCs were kept on the 6-well plate for 5 days and were analyzed by optical microscopy to confirm cell aggregation and growth. Separation procedures 1 and 2 allowed adequate isolation of MSCs and favored cell growth with the passage being carried out at 70% confluence after 15 days in culture. The cells could not be isolated using procedure 3. When the 3 castor oil polyurethane membrane types were compared it was possible to observe that the growth of MSCs was around 80% in membrane type 3, 20% in type 2, and 10% in type 1. Both Ficoll-Hypaque densities allow isolation of rat MSCs, and especially castor oil-based membrane type 3 may be used as a scaffold for MSCs.

  9. Effect of Aqueous Extract of Acacia nilotica on Microbial and Castor ...

    African Journals Online (AJOL)

    Five (5) Albino rats of both sexes weighing between (85-125g) were used for each experiment and diarrhoea was induced using Castor oil. The extract showed remarkable anti-diarrhoea activity which was dose dependent at 100, 200 and 400mg evidenced by decrease in volume of intestinal content significantly different at ...

  10. Simultaneous allergen inactivation and detoxification of castor bean cake by treatment with calcium compounds

    International Nuclear Information System (INIS)

    Fernandes, K.V.; Deus-de-Oliveira, N.; Godoy, M.G.; Guimarães, Z.A.S.; Nascimento, V.V.; Melo, E.J.T. de; Freire, D.M.G.; Dansa-Petretski, M.; Machado, O.L.T.

    2012-01-01

    Ricinus communis L. is of great economic importance due to the oil extracted from its seeds. Castor oil has been used for pharmaceutical and industrial applications, as a lubricant or coating agent, as a component of plastic products, as a fungicide or in the synthesis of biodiesel fuels. After oil extraction, a castor cake with a large amount of protein is obtained. However, this by-product cannot be used as animal feed due to the presence of toxic (ricin) and allergenic (2S albumin) proteins. Here, we propose two processes for detoxification and allergen inactivation of the castor cake. In addition, we establish a biological test to detect ricin and validate these detoxification processes. In this test, Vero cells were treated with ricin, and cell death was assessed by cell counting and measurement of lactate dehydrogenase activity. The limit of detection of the Vero cell assay was 10 ng/mL using a concentration of 1.6 × 10 5 cells/well. Solid-state fermentation (SSF) and treatment with calcium compounds were used as cake detoxification processes. For SSF, Aspergillus niger was grown using a castor cake as a substrate, and this cake was analyzed after 24, 48, 72, and 96 h of SSF. Ricin was eliminated after 24 h of SSF treatment. The cake was treated with 4 or 8% Ca(OH) 2 or CaO, and both the toxicity and the allergenic properties were entirely abolished. A by-product free of toxicity and allergens was obtained

  11. Amelioration of Anti-Nutritive Effects of Castor Oil Seed ( Ricinus ...

    African Journals Online (AJOL)

    Three hundred and twenty (320) day old male broilers were used to investigate the amelioration of anti-nutritive effects of castor oil seed (Ricinus communis) meal in broilers' ration using natural fermentation and DL-Methionine supplementation. The experimental designed was a 4 × 2 factorial arrangement of dietary ...

  12. Differential Contribution of Malic Enzymes during Soybean and Castor Seeds Maturation.

    Directory of Open Access Journals (Sweden)

    Mariel Claudia Gerrard Wheeler

    Full Text Available Malic enzymes (ME catalyze the decarboxylation of malate generating pyruvate, CO2 and NADH or NADPH. In some organisms it has been established that ME is involved in lipids biosynthesis supplying carbon skeletons and reducing power. In this work we studied the MEs of soybean and castor, metabolically different oilseeds. The comparison of enzymatic activities, transcript profiles and organic acid contents suggest different metabolic strategies operating in soybean embryo and castor endosperm in order to generate precursors for lipid biosynthesis. In castor, the malate accumulation pattern agrees with a central role of this metabolite in the provision of carbon to plastids, where the biosynthesis of fatty acids occurs. In this regard, the genome of castor possesses a single gene encoding a putative plastidic NADP-ME, whose expression level is high when lipid deposition is active. On the other hand, NAD-ME showed an important contribution to the maturation of soybean embryos, perhaps driving the carbon relocation from mitochondria to plastids to support the fatty acids synthesis in the last stages of seed filling. These findings provide new insights into intermediary metabolism in oilseeds and provide new biotechnological targets to improve oil yields.

  13. Recycling of waste poly(ethylene terephthalate) with castor oil using microwave heating

    Czech Academy of Sciences Publication Activity Database

    Beneš, Hynek; Slabá, J.; Walterová, Zuzana; Rais, David

    2013-01-01

    Roč. 98, č. 11 (2013), s. 2232-2243 ISSN 0141-3910 R&D Projects: GA MPO 2A-2TP1/135 Institutional support: RVO:61389013 Keywords : poly(ethylene terephthalate) * castor oil * chemical recycling Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.633, year: 2013

  14. Synthesis and properties of radiation modified thermally cured castor oil based polyurethanes

    International Nuclear Information System (INIS)

    Mortley, Aba; Bonin, H.W.; Bui, V.T.

    2007-01-01

    Thermally cured polyurethanes were prepared from castor oil and hexamethylene diisocyanate (HMDI). Due to the long aliphatic chain of the castor oil component of polyurethane, thermal curing of castor oil based polyurethane (COPU) is limited by increasing polymer viscosity. To enhance further crosslinking, COPUs were exposed to doses up to 3.0 MGy produced by the mixed ionizing radiation field of a SLOWPOKE-2 research nuclear reactor. The physico-mechanical properties of castor oil based polyurethanes (COPU), unirradiated and irradiated, were characterized by mechanical tensile tests. A four-fold increase in modulus and tensile strength values from 0.930 to 4.365 MPa and 0.149 to 0.747 MPa, respectively, suggests improved physico-mechanical properties resulting from radiation. The changing areas of the carbonyl and the NH absorbance peaks and the disappearance of the isocyanate peak in the FTIR spectra as radiation progressed, indicates increased hydrogen bonding and intermolecular crosslinking, which is in agreement with the mechanical tests. Unchanging 13 C solid state NMR spectra imply limited sample degradation with increasing radiation

  15. Film-forming properties of castor oil polyol ester blends in elastohydrodynamic conditions

    Science.gov (United States)

    The viscosities and elastohydrodynamic (EHD) film thickness properties of binary blends of castor oil with polyol esters were determined experimentally. Predicted blend viscosity was calculated from the viscosity of the pure blend components. Measured viscosity values were closer to the values pre...

  16. Experimental investigation on performance and exhaust emissions of castor oil biodiesel from a diesel engine.

    Science.gov (United States)

    Shojaeefard, M H; Etgahni, M M; Meisami, F; Barari, A

    2013-01-01

    Biodiesel, produced from plant and animal oils, is an important alternative to fossil fuels because, apart from dwindling supply, the latter are a major source of air pollution. In this investigation, effects of castor oil biodiesel blends have been examined on diesel engine performance and emissions. After producing castor methyl ester by the transesterification method and measuring its characteristics, the experiments were performed on a four cylinder, turbocharged, direct injection, diesel engine. Engine performance (power, torque, brake specific fuel consumption and thermal efficiency) and exhaust emissions were analysed at various engine speeds. All the tests were done under 75% full load. Furthermore, the volumetric blending ratios of biodiesel with conventional diesel fuel were set at 5, 10, 15, 20 and 30%. The results indicate that lower blends of biodiesel provide acceptable engine performance and even improve it. Meanwhile, exhaust emissions are much decreased. Finally, a 15% blend of castor oil-biodiesel was picked as the optimized blend of biodiesel-diesel. It was found that lower blends of castor biodiesel are an acceptable fuel alternative for the engine.

  17. Prolonged local anesthetic action through slow release from poly (lactic acid co castor oil).

    Science.gov (United States)

    Sokolsky-Papkov, Marina; Golovanevski, Ludmila; Domb, Abraham J; Weiniger, Carolyn F

    2009-01-01

    To evaluate a new formulation of bupivacaine loaded in an injectable fatty acid based biodegradable polymer poly(lactic acid co castor oil) in prolonging motor and sensory block when injected locally. The polyesters were synthesized from DL: -lactic acid and castor oil with feed ratio of 4:6 and 3:7 w/w. Bupivacaine was dispersed in poly(fatty ester) liquid and tested for drug release in vitro. The polymer p(DLLA:CO) 3:7 loaded with 10% bupivacaine was injected through a 22G needle close to the sciatic nerve of ICR mice and the duration of sensory and motor nerve blockade was measured. The DL: -lactic acid co castor oil p(DLLA:CO) 3:7 released 65% of the incorporated bupivacaine during 1 week in vitro. Single injection of 10% bupivacaine loaded into this polymer caused motor block that lasted 24 h and sensory block that lasted 48 h. Previously we developed a ricinoleic acid based polymer with incorporated bupivacaine which prolonged anesthesia to 30 h. The new polymer poly(lactic acid co castor oil) 3:7 provides slow release of effective doses of the incorporated local anesthetic agent and prolongs anesthesia to 48 h.

  18. Antimicrobial action of sodium hypochlorite and castor oil solutions for denture cleaning - in vitro evaluation.

    Science.gov (United States)

    Salles, Marcela Moreira; Oliveira, Viviane de Cássia; Souza, Raphael Freitas; Silva, Cláudia Helena Lovato; Paranhos, Helena de Freitas Oliveira

    2015-01-01

    The objective of this in vitro study was to evaluate the antimicrobial action of sodium hypochlorite (0.25% and 0.50%) and 10% castor oil solutions against specific microorganisms, by counting Colony Forming Units (CFU) of clinically important bacteria and Candida species. Acrylic resin specimens (n = 320; Lucitone 550) were obtained from square metal matrices (10 x 10 x 2 mm), sterilized by microwave (650W, for 6 minutes) and contaminated by Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Bacillus subtilis, Escherichia coli, Streptococcus mutans, Enterococcus faecalis and Candida glabrata. The specimens were immersed for 20 minutes in one of the following hygiene solutions (n = 10/each): A - 0.25% Sodium hypochlorite; B - 0.5% Sodium hypochlorite; C - 10% Castor oil solution; and D (Control) - saline. Adhered cells were suspended and inoculated into a selective solid medium (37ºC for 24 h). The Student's t-test (α = 0.05) was performed to compare log10(CFU+1)/mL between Groups C and D. The results showed that sodium hypochlorite (0.25% and 0.5%) completely eliminated all detectable microorganisms. The castor oil solution eliminated B. subtilis and reduced counts for other strains. Differences between C and D were significant (p castor oil solution provided moderate efficacy and performed differently on the tested species, with the strongest effect on B. subtilis and with non-significant action on E. faecalis.

  19. Coherent structures in the plasma edge turbulence of the RFX and CASTOR experiments

    Czech Academy of Sciences Publication Activity Database

    Martines, E.; Antoni, V.; Cavazzana, R.; Regnoli, G.; Serianni, G.; Hron, Martin; Stöckel, Jan

    2002-01-01

    Roč. 52, supplement D (2002), s. D13-D24 ISSN 0011-4626. [Symposium on Plasma Physics and Technology /20th./. Prague, 10.06.2002-13.06.2002] Institutional research plan: CEZ:AV0Z2043910 Keywords : CASTOR, coherent structures, plasma edge turbulence Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.311, year: 2002

  20. Effects The N-Hexane Extract Of Castor ( Ricinus Communis ) Seeds ...

    African Journals Online (AJOL)

    Materials and methods: The seeds of Castor plant were obtained, dried, pulverized, and exhaustively soxhlex extracted in N-hexane at 750C for 72 hours. This was dissolved in appropriate volumes of corn oil to make a concentration of 20mg/ml. The extract was administered to twenty –five (25) adult wistar rats at a dose of ...

  1. Differential Contribution of Malic Enzymes during Soybean and Castor Seeds Maturation.

    Science.gov (United States)

    Gerrard Wheeler, Mariel Claudia; Arias, Cintia Lucía; Righini, Silvana; Badia, Mariana Beatriz; Andreo, Carlos Santiago; Drincovich, María Fabiana; Saigo, Mariana

    2016-01-01

    Malic enzymes (ME) catalyze the decarboxylation of malate generating pyruvate, CO2 and NADH or NADPH. In some organisms it has been established that ME is involved in lipids biosynthesis supplying carbon skeletons and reducing power. In this work we studied the MEs of soybean and castor, metabolically different oilseeds. The comparison of enzymatic activities, transcript profiles and organic acid contents suggest different metabolic strategies operating in soybean embryo and castor endosperm in order to generate precursors for lipid biosynthesis. In castor, the malate accumulation pattern agrees with a central role of this metabolite in the provision of carbon to plastids, where the biosynthesis of fatty acids occurs. In this regard, the genome of castor possesses a single gene encoding a putative plastidic NADP-ME, whose expression level is high when lipid deposition is active. On the other hand, NAD-ME showed an important contribution to the maturation of soybean embryos, perhaps driving the carbon relocation from mitochondria to plastids to support the fatty acids synthesis in the last stages of seed filling. These findings provide new insights into intermediary metabolism in oilseeds and provide new biotechnological targets to improve oil yields.

  2. Apis mellifera pollination improves agronomic productivity of anemophilous castor bean (Ricinus communis).

    Science.gov (United States)

    Rizzardo, Rômulo A G; Milfont, Marcelo O; Silva, Eva M S da; Freitas, Breno M

    2012-12-01

    Castor bean (Ricinus communis L.) is cultivated mainly for biodiesel production because of its oil-rich seeds; it is assumed to be an anemophylous species. But pollination deficit can lead to low productivity often attributed to other reasons. In this paper, we investigated pollination requirements, pollination mechanism, occurrence of pollination deficit, and the role of biotic pollinators in a large commercial plantation of castor bean. Our results show that R. communis bears a mixed breeding system favoring selfing by geitonogamy, although the wind promotes mostly outcrossing. We also found that the honey bee (Apis mellifera L.) foraging on castor bean can both transfer pollen from male to female flowers within the same raceme and boost the release of airborne pollen by male flowers. Both situations increase geitonogamy rates, raising significantly fruit set and seed yield. This is the first report of an animal foraging activity increasing seed yield in an anemophilous and geitonogamous crop and elucidates the role of biotic pollinators in castor bean reproduction.

  3. Evaluation of the performance of a castor-oil based formulation in limiting pesticide residues in strawberry crops

    Directory of Open Access Journals (Sweden)

    Mário Sérgio Galhiane

    2012-01-01

    Full Text Available A study was made to evaluate the effect of a castor oil-based detergent on strawberry crops treated with different classes of pesticides, namely deltamethrin, folpet, tebuconazole, abamectin and mancozeb, in a controlled environment. Experimental crops of greenhouse strawberries were cultivated in five different ways with control groups using pesticides and castor oil-based detergent. The results showed that the group 2, which was treated with castor oil-based detergent, presented the lowest amount of pesticide residues and the highest quality of fruit produced.

  4. Burning plasma simulation and environmental assessment of tokamak, spherical tokamak and helical reactors

    International Nuclear Information System (INIS)

    Yamazaki, K.; Uemura, S.; Oishi, T.; Arimoto, H.; Shoji, T.; Garcia, J.

    2009-01-01

    Reference 1-GWe DT reactors (tokamak TR-1, spherical tokamak ST-1 and helical HR-1 reactors) are designed using physics, engineering and cost (PEC) code, and their plasma behaviours with internal transport barrier operations are analysed using toroidal transport analysis linkage (TOTAL) code, which clarifies the requirement of deep penetration of pellet fuelling to realize steady-state advanced burning operation. In addition, economical and environmental assessments were performed using extended PEC code, which shows the advantage of high beta tokamak reactors in the cost of electricity (COE) and the advantage of compact spherical tokamak in life-cycle CO 2 emission reduction. Comparing with other electric power generation systems, the COE of the fusion reactor is higher than that of the fission reactor, but on the same level as the oil thermal power system. CO 2 reduction can be achieved in fusion reactors the same as in the fission reactor. The energy payback ratio of the high-beta tokamak reactor TR-1 could be higher than that of other systems including the fission reactor.

  5. Tokamak residual zonal flow level in near-separatrix region

    International Nuclear Information System (INIS)

    Bing-Ren, Shi

    2010-01-01

    Residual zonal flow level is calculated for tokamak plasmas in the near-separatrix region of a diverted tokamak. A recently developed method is used to construct an analytic divertor tokamak configuration. It is shown that the residual zonal flow level becomes smaller but still keeps finite near the separatrix because the neoclassical polarisation mostly due to the trapped particles goes larger in this region. (fluids, plasmas and electric discharges)

  6. First divertor operation on the HL-2A tokamak

    International Nuclear Information System (INIS)

    Yang Qingwei; Ding Xuantong; Yan Longwen; Xuan Weimin; Liu Dequan; Chen Liaoyuan; Song Xianming; Yuan Baoshan; Zhang Jinhua; Cao Zeng; Li Xiaodong; Mao Weicheng; Zhou Caipin; Wang Enyao; Yan Jiancheng; Liu Yong

    2004-01-01

    HL-2A device is the first divertor tokamak in China. One of its main subjects is to study the features of the divertor plasma. In the last campaign, the first divertor configuration has been achieved and sustained on the HL-2A tokamak. Here authors give a brief description about the HL-2A tokamak, diagnostics arrangements, and the equilibrium analysis results on divertor configuration. The main results of divertor experiments are also presented. (author)

  7. Summary of the 1982 small tokamak users meeting

    International Nuclear Information System (INIS)

    Sprott, J.C.

    1982-11-01

    On November 1, 1982, the sixth in a series of approximately annual meetings of the users of small tokamaks was held in conjunction with the APS Division of Plasma Physics meeting at New Orleans. The meeting lasted three hours, with 34 people attending. The interest was on strengthening the ties between the small tokamaks and the large tokamaks. Accordingly, the latest meeting was dedicated to this theme, and in contrast to previous meetings, a few representatives from the large tokamaks were invited to attend and make presentations. Summaries of the various talks are included

  8. Castor beans hulls as a replacement for Tifton 85 hay in lamb diets.

    Science.gov (United States)

    de Paula Xavier de Andrade, Rafael; de Andrade Ferreira, Marcelo; Urbano, Stela Antas; de Azevedo, Marcílio; Félix, Sabrina Carla Rodrigues; de Siqueira, Michelle Christina Bernardo; Alves, Felipe José Lins; Chagas, Juana Catarina Cariri

    2013-06-01

    The objective of this study was to evaluate the effect of replacing Tifton 85 hay (0, 33, 66, or 100 %) with by castor bean hulls on the intake and nutrient digestibility and performance of 28 noncastrated lambs, averaging 7 months in age, 19.5 ± 2.0 kg average live weight, fed on diets based on forage cactus. The animals were housed in individual pens for 100 days. The digestibility trial occurred 40 days after the start of the performance using LIPE® as an external indicator for estimating fecal dry matter production. The replacement of hay with Castor beans hulls linearly decreased the intakes of dry matter, neutral detergent fiber, organic matter, and crude protein and reduced the digestibility coefficients of the dry matter, neutral detergent fiber, organic matter content, crude protein, and total digestible nutrient content. The hot carcass and true carcass yields were not influenced by the treatments and the feed conversion increased linearly. The empty body weight, live weight at slaughter, hot and cold carcass weights, total gain, and average daily gain decreased linearly with the replacement. The replacement of Tifton 85 hay with castor bean hulls reduced the intake of dry matter, crude protein and energy, consequently reducing the performance of the animals. However, as the regression coefficients were of low magnitude, data were subjected to analysis of variance and means were compared using the Dunnett test with diet without castor bean hulls set as the control treatment. The Tifton 85 hay can be replaced up to 66 % by castor bean hulls in finishing diets for lambs.

  9. Effect of castor oil emulsion eyedrops on tear film composition and stability.

    Science.gov (United States)

    Maïssa, Cécile; Guillon, Michel; Simmons, Peter; Vehige, Joseph

    2010-04-01

    An emulsion eyedrop containing castor oil has been shown to modify the tear film lipid layer and increase tear film stability. The primary objectives of this investigation were to measure the prevalence of castor oil in the tear fluid over time and quantify the effects on the lipid layer. A secondary objective was to quantify the initial effects on ocular symptomatology. The investigation was an open label pilot study on 5 normal and 10 dry eye subjects. A single eyedrop (Castor oil emulsion, Allergan) was instilled in each eye; the tear film appearance and composition were monitored for 4h via in vivo visualisation using the Tearscope and post in vivo tear samples analysis by HPLC. Combined results for both normal and dry eye subjects showed that castor oil was detected up to 4h after a single eyedrop instillation and associated with an increase in the level of tear film lipid. The relative amount of various lipid families was also changed. An increase in tear lipid layer thickness was significant up to one hour post-instillation for the symptomatic sub-population. The changes in tear film characteristics were associated with significantly lower symptoms up to four hours post-instillation for the symptomatic sub-population. This pilot investigation showed that castor oil eyedrops achieved a residence time of at least four hours post-instillation, producing a more stable tear film and an associated significant decrease in ocular symptoms over the entire follow-up period for the symptomatic subjects. 2009 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  10. Eddy currents in the Alcator Tokamak

    International Nuclear Information System (INIS)

    Schram, D.C.; Rem, J.

    1975-03-01

    A one-dimensional model of an aircore transformer has been developed through which it is possible to analyze the effect of eddy currents in the primary windings and of similar currents in the field coils for the toroidal magnetic field, on the time dependence of the current in a Tokamak experiment. The model is applied to the 'Alcator' Tokamak at MIT and its accuracy is tested by comparing analytical results for the harmonic behaviour of the transformer, with experimental data. The time-dependent behaviour of the plasma current for a constant plasma resistance shows that eddy currents in the primary windings will lead to a reduction of 8% of the current maximum. The eddy currents in the 'Bitter' coils are found to affect predominantly the initial current rise; they lead to a steepening of the current rise. Finally, the influence of the time dependence of the plasma resistance is investigated

  11. Microinstability theory in tokamaks: a review

    Energy Technology Data Exchange (ETDEWEB)

    Tang, W.M.

    1977-06-01

    Significant investigations in the area of tokamak microinstability theory are reviewed. Emphasis is given to the work covering the period from 1970 through 1976. Special attention is focused on low-frequency electrostatic drift-type modes, which are generally believed to be the dominant tokamak microinstabilities under normal operating conditions. The basic linear formalism including electromagnetic (finite beta) modifications is presented along with a general survey of the numerous papers investigating specific linear and nonlinear effects on these modes. Estimates of the associated anomalous transport and confinement times are discussed, and a summary of relevant experimental results is given. Studies of the nonelectrostatic and high-frequency instabilities associated with the presence of high energy ions from neutral beam injection (or with the presence of alpha particles from fusion reactions) are also surveyed.

  12. Comparison between stellarator and tokamak divertor transport

    International Nuclear Information System (INIS)

    Feng, Y.; Lunt, T.; Kobayashi, M.; Reiter, D.

    2010-11-01

    The paper compares the essential divertor transport features of the poloidal divertor, which is well-developed for tokamaks, and the non-axisymmetric divertors currently investigated on helical devices. It aims at surveying the fundamental similarities and differences in divertor concept and geometry, and their consequences for how the divertor functions. In particular, the importance of various transport terms governing axisymmetric and helical scrape-off-layers (SOLs) is examined, with special attention being paid to energy, momentum and impurity transport. Tokamak and stellarator SOLs are compared by identifying key geometric parameters through which the governing physics can be illustrated by simple models and estimates. More quantitative assessments rely nevertheless on the modeling using EMC3-EIRENE code. Most of the theoretical results are discussed in conjunction with experimental observations. (author)

  13. Assembly study for JT-60SA tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Shibanuma, K., E-mail: shibanuma.kiyoshi@jaea.go.jp [Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan); Arai, T.; Hasegawa, K.; Hoshi, R.; Kamiya, K.; Kawashima, H.; Kubo, H.; Masaki, K.; Saeki, H.; Sakurai, S.; Sakata, S.; Sakasai, A.; Sawai, H.; Shibama, Y.K.; Tsuchiya, K.; Tsukao, N.; Yagyu, J.; Yoshida, K.; Kamada, Y. [Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan); Mizumaki, S. [Toshiba Corporation, Minato-ku, Tokyo 105-8001 (Japan); and others

    2013-10-15

    The assembly scenarios and assembly tools of the major tokamak components for JT-60SA are studied in the following. (1) The assembly frame (with a dedicated 30-tonne crane), which is located around the JT-60SA tokamak, is adopted for effective assembly works in the torus hall and the temporary support of the components during assembly. (2) Metrology for precise positioning of the components is also studied by defining the metrology points on the components. (3) The sector segmentation for weld joints and positioning of the vacuum vessel (VV), the assembly scenario and tools for VV thermal shield (TS), the connection of the outer intercoil structure (OIS) and the installation of the final toroidal field coil (TFC) are studied, as typical examples of the assembly scenarios and tools for JT-60SA.

  14. Start of the international tokamak physics activity

    International Nuclear Information System (INIS)

    Campbell, D.

    2001-01-01

    This newsletter comprises a summary on the start of the International Tokamak Physics activity (ITPA) by Dr. D. Campbell, Chair of the ITPA Co-ordinating Committee. As the ITER EDA drew to a close, it became clear that it was desirable to establish a new mechanism in order to promote the continued development of the physics basis for burning plasma experiments and to preserve the invaluable collaborations between the major international fusion communities which had been established through the ITER physics expert groups. As a result of the discussions of the representatives of the European Union, Japan, the Russian Federation and the United States the agreed principles for conducting the International Tokamak Physics Activity (ITPA) were elaborated and ITPA topical physics groups were organized

  15. International tokamak reactor conceptual design overview

    International Nuclear Information System (INIS)

    Stacey, W.M. Jr.

    1981-01-01

    The International Tokamak Reactor (INTOR) Workshop is an unique collaborative effort among Euratom, Japan, the USA and USSR. The Zero-Phase of the INTOR Workshop, which was conducted during 1979, assessed the technical data base that would support the construction of the next major device in the tokamak program to operate in the early 1990s and defined the objectives and characteristics of this device. The INTOR workshop was extended into phase-1, the Definition Phase, in early 1980. The objective of the Phase-1 Workshop was to develop a conceptual design of the INTOR experiment. The purpose of this paper is to give an overview of the work of the Phase-1 INTOR Workshop (January 1980-June 1981, with emphasis upon the conceptual design

  16. Metal impurity release in diverted tokamak discharges

    International Nuclear Information System (INIS)

    Staudenmaier, G.; Wampler, W.R.

    1986-01-01

    Plasma materials interaction at the wall of the main plasma chamber of the divertor tokamak ASDEX was investigated by a combined probe, allowing simultaneous measurements of the erosion rate by neutral particles, and the flux and average energy of neutrals. The erosion was measured by collecting part of the released material on a carbon strip. Subsequent surface analysis was performed by electron induced x-ray analysis. Flux and energy of the impinging neutral particles were measured after each single discharge with an energy resolving carbon resistance probe. Such combined measurements yield the erosion yield being characteristic for the erosion process. Data for ohmic discharges in deuterium and helium are compared. It turns out that the carbon resistance probe is a simple but powerful means to study the metal impurity release from the tokamak walls by charge exchange neutrals

  17. Tokamak Fusion Core Experiment maintenance study

    International Nuclear Information System (INIS)

    Snyder, A.M.; Watts, K.D.

    1985-01-01

    The recently completed Tokamak Fusion Core Experiment (TFCX) design project was carried out to investigate potential next generation tokamak concepts. An important aspect of this project was the early development and incorporation of remote maintainability throughout the design process. This early coordination and incorporation of maintenance aspects to the design of the device and facilities would assure that the machine could ultimately be maintained and repaired in an efficient and cost effective manner. To meet this end, a rigorously formatted engineering trade study was performed to determine the preferred configuration for the TFCX reactor based primarily on maintenance requirements. The study indicated that the preferred design was one with an external vacuum vessel and torrodial field coils that could be removed via a simple radial motion. The trade study is presented and the preferred TFCX configuration is described

  18. Boundary Plasma Turbulence Simulations for Tokamaks

    International Nuclear Information System (INIS)

    Xu, X.; Umansky, M.; Dudson, B.; Snyder, P.

    2008-05-01

    The boundary plasma turbulence code BOUT models tokamak boundary-plasma turbulence in a realistic divertor geometry using modified Braginskii equations for plasma vorticity, density (ni), electron and ion temperature (T e ; T i ) and parallel momenta. The BOUT code solves for the plasma fluid equations in a three dimensional (3D) toroidal segment (or a toroidal wedge), including the region somewhat inside the separatrix and extending into the scrape-off layer; the private flux region is also included. In this paper, a description is given of the sophisticated physical models, innovative numerical algorithms, and modern software design used to simulate edge-plasmas in magnetic fusion energy devices. The BOUT code's unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics

  19. Runaway-ripple interaction in Tokamaks

    International Nuclear Information System (INIS)

    Laurent, L.; Rax, J.M.

    1989-08-01

    Two approaches of the interaction between runaway electrons and the ripple field, in tokamaks, are discussed. The first approach considers the resonance effect as an intense cyclotron heating of the electrons, by the ripple field, in the guiding center frame of the fast particles. In the second approach, an Hamiltonian formalism is used. A criterion for the onset of chaotic behavior and the results are given. A new universal instability of the runaway population in tokamak configuration is found. When combined with cyclotron losses one of its major consequence is to act as an effective slowing down mechanism preventing the free fall acceleration toward the synchrotron limit. This configuration allows the explanation of some experimental results of Tore Supra and Textor

  20. Neural net prediction of tokamak plasma disruptions

    International Nuclear Information System (INIS)

    Hernandez, J.V.; Lin, Z.; Horton, W.; McCool, S.C.

    1994-10-01

    The computation based on neural net algorithms in predicting minor and major disruptions in TEXT tokamak discharges has been performed. Future values of the fluctuating magnetic signal are predicted based on L past values of the magnetic fluctuation signal, measured by a single Mirnov coil. The time step used (= 0.04ms) corresponds to the experimental data sampling rate. Two kinds of approaches are adopted for the task, the contiguous future prediction and the multi-timescale prediction. Results are shown for comparison. Both networks are trained through the back-propagation algorithm with inertial terms. The degree of this success indicates that the magnetic fluctuations associated with tokamak disruptions may be characterized by a relatively low-dimensional dynamical system

  1. Lower hybrid current drive in shaped tokamaks

    International Nuclear Information System (INIS)

    Kesner, J.

    1993-01-01

    A time dependent lower hybrid current drive tokamak simulation code has been developed. This code combines the BALDUR tokamak simulation code and the Bonoli/Englade lower hybrid current drive code and permits the study of the interaction of lower hybrid current drive with neutral beam heating in shaped cross-section plasmas. The code is time dependent and includes the beam driven and bootstrap currents in addition to the current driven by the lower hybrid system. Examples of simulations are shown for the PBX-M experiment which include the effect of cross section shaping on current drive, ballooning mode stabilization by current profile control and sawtooth stabilization. A critical question in current drive calculations is the radial transport of the energetic electrons. The authors have developed a response function technique to calculate radial transport in the presence of an electric field. The consequences of the combined influences of radial diffusion and electric field acceleration are discussed

  2. The physics of tokamak start-up

    International Nuclear Information System (INIS)

    Mueller, D.

    2013-01-01

    Tokamak start-up on present-day devices usually relies on inductively induced voltage from a central solenoid. In some cases, inductive startup is assisted with auxiliary power from electron cyclotron radio frequency heating. International Thermonuclear Experimental Reactor, the National Spherical Torus Experiment Upgrade and JT60, now under construction, will make use of the understanding gained from present-day devices to ensure successful start-up. Design of a spherical tokamak (ST) with DT capability for nuclear component testing would require an alternative to a central solenoid because the small central column in an ST has insufficient space to provide shielding for the insulators in the solenoid. Alternative start-up techniques such as induction using outer poloidal field coils, electron Bernstein wave start-up, coaxial helicity injection, and point source helicity injection have been used with success, but require demonstration of scaling to higher plasma current

  3. Magnetic sensor for steady state tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Neyatani, Yuzuru; Mori, Katsuharu; Oguri, Shigeru; Kikuchi, Mitsuru [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1996-06-01

    A new type of magnetic sensor has been developed for the measurement of steady state magnetic fields without DC-drift such as integration circuit. The electromagnetic force induced to the current which leads to the sensor was used for the measurement. For the high frequency component which exceeds higher than the vibration frequency of sensor, pick-up coil was used through the high pass filter. From the results using tokamak discharges, this sensor can measure the magnetic field in the tokamak discharge. During {approx}2 hours measurement, no DC drift was observed. The sensor can respond {approx}10ms of fast change of magnetic field during disruptions. We confirm the extension of measured range to control the current which leads to the sensor. (author).

  4. The tokamak - an imperfect frame of refernce

    International Nuclear Information System (INIS)

    Schmitter, K.U.

    1981-03-01

    It is attempted to assess the suitability of tokamaks for fusion power plants on the basis of existing design studies by reference to the reality of energy production in fission power plants. A definition of suitability criteria and a discussion of their relation to the most important features of power plants are followed by a comparative treatment. For example, the mean volumetric net electric power density in the nuclear islands of tokamak power plant designs is only 2,5 to 4 E of the value common today in light water reactor nuclear islands. In addition, configuration problems, auxiliary power requirements and energy payback time are discussed and taken into account in the assessment. (orig.)

  5. Tensor pressure tokamak equilibrium and stability

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, W.A.

    1981-03-01

    We investigate the equilibrium and magnetohydrodynamic (MHD) stability of tokamaks with tensor pressure and examine, in particular, the effects of anisotropies induced by neutral beam injection. Perpendicular and parallel beam pressure components are evaluated by taking moments of a distribution function obtained from the solution of a Fokker-Planck equation that models the injection of high-energy neutral beams into a tokamak. We numerically generate D-shaped beam-induced tensor pressure equilibria. A double adiabatic energy principle is derived from a modified version of the guiding center plasma energy principle. Finally, we apply the tensor pressure ballooning mode equation to computed equilibria that model experimentally determined ISX-B discharge profiles with high-power neutral beam injection. We predict that the plasma is unstable to flutelike modes in the central core of the discharge as a result of the pressure profile peakedness induced by the beams.

  6. Tore Supra. Basic design Tokamak system

    International Nuclear Information System (INIS)

    Aymar, R.; Bareyt, B.; Bon Mardion, G.

    1980-10-01

    This document describes the basic design for the main components of the Tokamak system of Tora Supra. As such, it focuses on the engineering problems, and refers to last year report on Tora Supra (EUR-CEA-1021) for objectives and experimental programme of the apparatus on one hand, and for qualifying tests of the main technical solutions on the other hand. Superconducting toroidal field coil system, vacuum vessels and radiation shields, poloidal field system and cryogenic system are described

  7. Microinstabilities in weak density gradient tokamak systems

    Energy Technology Data Exchange (ETDEWEB)

    Tang, W.M.; Rewoldt, G.; Chen, L.

    1986-04-01

    A prominent characteristic of auxiliary-heated tokamak discharges which exhibit improved (''H-mode type'') confinement properties is that their density profiles tend to be much flatter over most of the plasma radius. Depsite this favorable trend, it is emphasized here that, even in the limit of zero density gradient, low-frequency microinstabilities can persist due to the nonzero temperature gradient.

  8. Confinement scaling and ignition in tokamaks

    International Nuclear Information System (INIS)

    Perkins, F.W.; Sun, Y.C.

    1985-10-01

    A drift wave turbulence model is used to compute the scaling and magnitude of central electron temperature and confinement time of tokamak plasmas. The results are in accord with experiment. Application to ignition experiments shows that high density (1 to 2) . 10 15 cm -3 , high field, B/sub T/ > 10 T, but low temperature T approx. 6 keV constitute the optimum path to ignition

  9. Electron cyclotron emission from the PLT tokamak

    International Nuclear Information System (INIS)

    Hosea, J.; Arunasalam, V.; Cano, R.

    1977-07-01

    Experimental measurements of electron cyclotron emission from the PLT tokamak plasma reveal that black-body emission occurs at the fundamental frequency. Such emission, not possible by direct thermal excitation of electromagnetic waves, is herein attributed to thermal excitation of electrostatic (Bernstein) waves which then mode convert into electromagnetic waves. The local feature of the electrostatic wave generation permits spatially and time resolved measurements of electron temperature as for the second harmonic emission

  10. MHD stability of an almost circular tokamak

    International Nuclear Information System (INIS)

    Roy, A.

    1990-10-01

    In a tokamak, the ratio β between the plasma pressure and that of the magnetic field is limited by the appearance of instabilities. The magnetic field in a tokamak reactor will always be limited by technological constraints. It is therefore crucial to know what factors have an effect on the β limit, since a zero resistivity plasma fluid model allows for theoretical reproduction of the β limits observed experimentally. Theoretical studies have shown that the distributions of pressure and current density may have a substantial effect on the β limit. The effect of the current density and pressure distributions on the β limit has been studied for tokamak with a circular core section. The best results are obtained when the current density is concentrated in the centre of the section and is nil at the periphery. But the second region of stability against ballooning modes cannot be obtained in a circular tokamak owing to the destabilisation of the universal modes. This study was then extended to the stability of plasmas the section of which is almost circular and has a point of reflection. Such configurations are vital for fusion since they allow systems in which the confinement time does not deteriorate with an increase in the additional heating power. The β limit was calculated for different positions of the reflection point. The results show that when it is displaced from the interior towards the exterior of the torus, the stability of the overall modes is progressively improved until it is vertical. But if the point of reflection is further displaced from this vertical position towards the exterior of the torus, localised modes close to the edge of the plasma are destabilised and bring about a drop in the β limit. (author) figs., tabs., 80 refs

  11. Neoclassical tearing modes in a tokamak

    International Nuclear Information System (INIS)

    Hahm, T.S.

    1988-08-01

    Linear tearing instability is studied in the banana collisionality regime in tokamak geometry. Neoclassical effects produce significant modifications of Ohm's law and the vorticity equation so that the growth rate of tearing modes driven by Δ' is dramatically reduced compared to the usual resistive MHD value. Consequences of this result, regarding the presence of pressure-gradient-driven neoclassical resistive interchange instabilities and the evolution of magnetic islands in the Rutherford regime, are discussed. 10 refs

  12. Shielding and maintainability in an experimental tokamak

    International Nuclear Information System (INIS)

    Abdou, M.A.; Fuller, G.; Hager, E.R.; Vogelsang, W.F.

    1979-01-01

    This paper presents the results of an attempt to develop an understanding of the various factors involved. This work was performed as a part of the task assigned to one of the expert groups on the International Tokamak Reactor (INTOR). The shielding penalties for requiring personnel access are quantified. This is followed by a quantitative estimate of the benefits associated with personnel access. The penalties to the benefits and conclusions and recommendations on resolving the issue are discussed

  13. Axisymmetric instability in a noncircular tokamak

    International Nuclear Information System (INIS)

    Lipschultz, B.

    1979-10-01

    The stability of dee, inverse-dee and square cross section plasmas to axisymmetric modes has been investigated experimentally in Tokapole II, a tokamak with a four-null poloidal divertor. Experimental results are closely compared with predictions of two numerical stability codes - the PEST code (ideal MHD, linear stability) adapted to tokapole geometry and a code which follows the nonlinear evolution of shapes similar to tokapole equilibria

  14. Tokamak with liquid metal toroidal field coil

    International Nuclear Information System (INIS)

    Ohkawa, T.; Schaffer, M.J.

    1981-01-01

    Tokamak apparatus includes a pressure vessel for defining a reservoir and confining liquid therein. A toroidal liner disposed within the pressure vessel defines a toroidal space within the liner. Liquid metal fills the reservoir outside said liner. Electric current is passed through the liquid metal over a conductive path linking the toroidal space to produce a toroidal magnetic field within the toroidal space about the major axis thereof. Toroidal plasma is developed within the toroidal space about the major axis thereof

  15. Discrete Alfven waves in the TORTUS tokamak

    International Nuclear Information System (INIS)

    Amagishi, Y.; Ballico, M.J.; Cross, R.C.; Donnely, I.J.

    1989-01-01

    Discrete Alfven Waves (DAWs) have been observed as antenna resistance peaks and as enhanced edge fields in the TORTUS tokamak during Alfven wave heating experiments. A kinetic theory code has been used to calculate the antenna loading and the structure of the DAW fields for a range of plasma current and density profiles. There is fair agreement between the measured and predicted amplitude of the DAW fields in the plasma edge when both are normalized to the same antenna power

  16. Comparison of tokamak burn cycle options

    International Nuclear Information System (INIS)

    Ehst, D.A.; Brooks, J.N.; Cha, Y.; Evans, K. Jr.; Hassanein, A.M.; Kim, S.; Majumdar, S.; Misra, B.; Stevens, H.C.

    1985-01-01

    Experimental confirmation of noninductive current drive has spawned a number of suggestions as to how this technique can be used to extend the fusion burn period and improve the reactor prospects of tokamaks. Several distinct burn cycles, which employ various combinations of Ohmic and noninductive current generation, are possible, and we will study their relative costs and benefits for both a commerical reactor as well as an INTOR-class device. We begin with a review of the burn cycle options

  17. Multiple mode model of tokamak transport

    International Nuclear Information System (INIS)

    Singer, C.E.; Ghanem, E.S.; Bateman, G.; Stotler, D.P.

    1989-07-01

    Theoretical models for radical transport of energy and particles in tokamaks due to drift waves, rippling modes, and resistive ballooning modes have been combined in a predictive transport code. The resulting unified model has been used to simulate low confinement mode (L-mode) energy confinement scalings. Dependence of global energy confinement on electron density for the resulting model is also described. 26 refs., 1 fig., 2 tabs

  18. Physics parameter space of tokamak ignition devices

    International Nuclear Information System (INIS)

    Selcow, E.C.; Peng, Y.K.M.; Uckan, N.A.; Houlberg, W.A.

    1985-01-01

    This paper describes the results of a study to explore the physics parameter space of tokamak ignition experiments. A new physics systems code has been developed to perform the study. This code performs a global plasma analysis using steady-state, two-fluid, energy-transport models. In this paper, we discuss the models used in the code and their application to the analysis of compact ignition experiments. 8 refs., 8 figs., 1 tab

  19. Modeling tokamak discharges with current holes

    International Nuclear Information System (INIS)

    Jensen, T.H.

    2002-01-01

    Tokamaks with current holes [T.S. Taylor, et al., Bull. Am. Phys. Soc. 43 (1998) 1783; N.C. Hawkes, et al., Phys. Rev. Lett. 87 (2001) 115001; T. Fujita, et al., Phys. Rev. Lett. 87 (2001) 245001] are interesting, in part, because discharges with true current holes do not consume poloidal flux. The modeling of this Letter suggests that under steady-state conditions their currents may be driven by radial flow of plasma resulting from neutral beam injection

  20. User's manual of Tokamak Simulation Code

    International Nuclear Information System (INIS)

    Nakamura, Yukiharu; Nishino, Tooru; Tsunematsu, Toshihide; Sugihara, Masayoshi.

    1992-12-01

    User's manual for use of Tokamak Simulation Code (TSC), which simulates the time-evolutional process of deformable motion of axisymmetric toroidal plasma, is summarized. For the use at JAERI computer system, the TSC is linked with the data management system GAEA. This manual is forcused on the procedure for the input and output by using the GAEA system. Model equations to give axisymmetric motion, outline of code system, optimal method to get the well converged solution are also described. (author)

  1. Coherent structures in tokamak plasmas workshop: Proceedings

    International Nuclear Information System (INIS)

    Koniges, A.E.; Craddock, G.G.

    1992-08-01

    Coherent structures have the potential to impact a variety of theoretical and experimental aspects of tokamak plasma confinement. This includes the basic processes controlling plasma transport, propagation and efficiency of external mechanisms such as wave heating and the accuracy of plasma diagnostics. While the role of coherent structures in fluid dynamics is better understood, this is a new topic for consideration by plasma physicists. This informal workshop arose out of the need to identify the magnitude of structures in tokamaks and in doing so, to bring together for the first time the surprisingly large number of plasma researchers currently involved in work relating to coherent structures. The primary purpose of the workshop, in addition to the dissemination of information, was to develop formal and informal collaborations, set the stage for future formation of a coherent structures working group or focus area under the heading of the Tokamak Transport Task Force, and to evaluate the need for future workshops on coherent structures. The workshop was concentrated in four basic areas with a keynote talk in each area as well as 10 additional presentations. The issues of discussion in each of these areas was as follows: Theory - Develop a definition of structures and coherent as it applies to plasmas. Experiment - Review current experiments looking for structures in tokamaks, discuss experimental procedures for finding structures, discuss new experiments and techniques. Fluids - Determine how best to utilize the resource of information available from the fluids community both on the theoretical and experimental issues pertaining to coherent structures in plasmas. Computation - Discuss computational aspects of studying coherent structures in plasmas as they relate to both experimental detection and theoretical modeling

  2. Development of Atomic Beam Probe for tokamaks

    Czech Academy of Sciences Publication Activity Database

    Berta, M.; Anda, G.; Aradi, M.; Bencze, A.; Buday, Cs.; Kiss, I.G.; Tulipán, Sz.; Veres, G.; Zoletnik, S.; Havlíček, Josef; Háček, Pavel

    2013-01-01

    Roč. 88, č. 11 (2013), s. 2875-2880 ISSN 0920-3796 R&D Projects: GA MŠk(CZ) LM2011021 Institutional support: RVO:61389021 Keywords : ABP * Plasma diagnostics * COMPASS tokamak * Current density * Plasma density profile measurement Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.149, year: 2013 http://www.sciencedirect.com/science/article/pii/S0920379613005048#

  3. High beta plasmas in the PBX tokamak

    International Nuclear Information System (INIS)

    Bol, K.; Buchenauer, D.; Chance, M.

    1986-04-01

    Bean-shaped configurations favorable for high β discharges have been investigated in the Princeton Beta Experiment (PBX) tokamak. Strongly indented bean-shaped plasmas have been successfully formed, and beta values of over 5% have been obtained with 5 MW of injected neutral beam power. These high beta discharges still lie in the first stability regime for ballooning modes, and MHD stability analysis implicates the external kink as responsible for the present β limit

  4. Multiple mode model of tokamak transport

    Energy Technology Data Exchange (ETDEWEB)

    Singer, C.E.; Ghanem, E.S.; Bateman, G.; Stotler, D.P.

    1989-07-01

    Theoretical models for radical transport of energy and particles in tokamaks due to drift waves, rippling modes, and resistive ballooning modes have been combined in a predictive transport code. The resulting unified model has been used to simulate low confinement mode (L-mode) energy confinement scalings. Dependence of global energy confinement on electron density for the resulting model is also described. 26 refs., 1 fig., 2 tabs.

  5. High beta plasmas in the PBX tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Bol, K.; Buchenauer, D.; Chance, M.; Couture, P.; Fishman, H.; Fonck, R.; Gammel, G.; Grek, B.; Ida, K.; Itami, K.

    1986-04-01

    Bean-shaped configurations favorable for high ..beta.. discharges have been investigated in the Princeton Beta Experiment (PBX) tokamak. Strongly indented bean-shaped plasmas have been successfully formed, and beta values of over 5% have been obtained with 5 MW of injected neutral beam power. These high beta discharges still lie in the first stability regime for ballooning modes, and MHD stability analysis implicates the external kink as responsible for the present ..beta.. limit.

  6. Small-scale tearing mode in tokamaks

    International Nuclear Information System (INIS)

    Ivanov, N.V.

    1983-01-01

    Considerations are given on the possible effect of small-scale tearing mode with m >> 1 on the plasma electron thermal conductivity in a tokamak. The estimate of the electron thermal conductivity coefficient is obtained. Calculation results are compared with experimental data. The calculated dependence of radial distribution of electron temperature is shown to vary weakly with the tn(m 2 /m 1 ) alteration everywhere, except for the vicinity of point r approximately 0

  7. First experiments with SST-1 tokamak

    International Nuclear Information System (INIS)

    Saxena, Y.C.

    2005-01-01

    SST-1, a steady state superconducting tokamak, is undergoing commissioning tests at the Institute for Plasma Research. The objectives of SST-1 include studying the physics of the plasma processes in a tokamak under steady state conditions and learning technologies related to the steady state operation of the tokamak. These studies are expected to contribute to the tokamak physics database for very long pulse operations. Superconducting (SC) magnets are deployed for both the toroidal and poloidal field coils in SST-1. An Ohmic transformer is provided for plasma breakdown and initial current ramp up. SST-1 deploys a fully welded ultra high vacuum vessel. Liquid nitrogen cooled radiation shield are deployed between the vacuum vessel and SC magnets as well as SC magnets and cryostat, to minimize the radiation losses at the SC magnets. The auxiliary current drive is based on 1.0 MW of Lower Hybrid current drive (LHCD) at 3.7 GHz. Auxiliary heating systems include 1 MW of Ion Cyclotron Resonance Frequency system (ICRF) at 22 MHz to 91 MHz, 0.2 MW of Electron Cyclotron Resonance heating at 84 GHz and a Neutral Beam Injection (NBI) system with peak power of 0.8 MW (at 80 keV) with variable beam energy in range of 10-80 keV. The ICRF system would also be used for initial breakdown and wall conditioning experiments. Detailed commissioning tests on the cryogenic system and experiments on the hydraulic characters and cool down features of single TF coils have been completed prior to the cool down of the entire superconducting system. Results of the single TF magnet cool down, and testing of the magnet system are presented. First experiments related to the breakdown and the current ramp up will subsequently be carried out. (author)

  8. Current drive for spherical tokamak plasmas

    International Nuclear Information System (INIS)

    Storer, R.

    1999-01-01

    Very low aspect ratio spherical tokamaks have proved to have some very useful and remarkable properties including very high values of the plasma pressure to magnetic field pressure. Following the construction of the Start tokamak, a number of such configurations have been constructed. One of the difficulties encountered is in providing sufficient inductive current drive due to the competing requirements of the need to keep the aspect ratio low and providing the space for the central current-carrying rod with an internal inductive coil. An alternative current drive technique would be very useful. In a parallel development it has been shown that a rotating magnetic field can drive a significant non-linear Hall current in a spherical plasma. Successful experiments of this concept have been made with a device called the Rotamak. In its original configuration this device was a field reversed configuration without a toroidal magnetic field but with a vertical field to establish the magnetic hydrodynamical equilibrium. However, recent modifications have shown that increased current can be driven if a central current-carrying rod is used to provide an applied toroidal field. The new Rotamak has then a spherical tokamak magnetic field structure. This work will present new calculations which model the above structure and include the effect of the applied toroidal field in addition to the steady vertical field and the rotating (current-drive) magnetic field. The problem is fully three dimensional and non-linear and involves the application of interesting computational techniques. The potential of using the rotating field current drive technique for spherical tokamaks will be evaluated

  9. Tokamaks: from A D Sakharov to the present (the 60-year history of tokamaks)

    International Nuclear Information System (INIS)

    Azizov, E A

    2012-01-01

    The paper is prepared on the basis of the report presented at the session of the Physical Sciences Division of the Russian Academy of Sciences (RAS) at the Lebedev Physical Institute, RAS on 25 May 2011, devoted to the 90-year jubilee of Academician Andrei D Sakharov - the initiator of controlled nuclear fusion research in the USSR. The 60-year history of plasma research work in toroidal devices with a longitudinal magnetic field suggested by Andrei D Sakharov and Igor E Tamm in 1950 for the confinement of fusion plasma and known at present as tokamaks is described in brief. The recent (2006) agreement among Russia, the EU, the USA, Japan, China, the Republic of Korea, and India on the joint construction of the international thermonuclear experimental reactor (ITER) in France based on the tokamak concept is discussed. Prospects for using the tokamak as a thermonuclear (14 MeV) neutron source are examined. (conferences and symposia)

  10. Accessibility of high. beta. tokamak states

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, J. T.

    1978-05-01

    Encouraging results with neutral beam heating and adiabatic compression of tokamak plasmas have prompted new experiments which will study the approach to high ..beta.. states. As projected tokamak ..beta.. values become nonnegligible (average ..beta.. of 4% is the goal), the models previously used for transport calculations will become inadequate. These models will be required to account for the evolution of the magnetic geometry, along with the change in plasma parameters. We present an axisymmetric transport model which should be useful for studying the approach to higher ..beta.. values in tokamak experiments. Results from transport calculations with this model allow us to draw a parallel between observed behavior in seemingly unrelated experiments: electron heating by neutral injection in the ORMAK device and adiabatic compression in the ATC experiment. Finally, we find that the nature of cross-field transport may be expected to change as significant ..beta.. values are reached. Enhanced transport from ballooning instabilities is likely to play a role as important as that now played by sawtooth (m = 1) and saturated (m = 2) instabilities. New techniques for describing this transport are required.

  11. Liquid tin limiter for FTU tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Vertkov, A., E-mail: avertkov@yandex.ru [JSC “Red Star”, Moscow (Russian Federation); Lyublinski, I. [JSC “Red Star”, Moscow (Russian Federation); NRNU MEPhI, Moscow (Russian Federation); Zharkov, M. [JSC “Red Star”, Moscow (Russian Federation); Mazzitelli, G.; Apicella, M.L.; Iafrati, M. [Associazione EURATOM-ENEA sulla Fusione, C. R. Frascati, Frascati, Rome, Italy, (Italy)

    2017-04-15

    Highlights: • First steady state operating liquid tin limiter TLL is under study on FTU tokamak. • The cooling system with water spray coolant for TLL has been developed and tested. • High corrosion resistance of W and Mo in molten Sn confirmed up to 1000 °C. • Wetting process with Sn has been developed for Mo and W. - Abstract: The liquid Sn in a matrix of Capillary Porous System (CPS) has a high potential as plasma facing material in steady state operating fusion reactor owing to its physicochemical properties. However, up to now it has no experimental confirmation in tokamak conditions. First steady state operating limiter based on the CPS with liquid Sn installed on FTU tokamak and its experimental study is in progress. Several aspects of the design, structural materials and operation parameters of limiter based on tungsten CPS with liquid Sn are considered. Results of investigation of corrosion resistance of Mo and W in Sn and their wetting process are presented. The heat removal for limiter steady state operation is provided by evaporation of flowing gaswater spray. The effectiveness of such heat removal system is confirmed in modelling tests with power flux up to 5 MW/m2.

  12. Experimental results from the TUMAN 3 tokamak

    International Nuclear Information System (INIS)

    Golant, V.E.; Andrejko, M.V.; Askinazi, L.G.; Korneev, V.A.; Krikunov, S.V.; Lipin, B.M.; Lebedev, S.V.; Levin, L.S.; Podushnikova, K.A.; Razdobarin, G.T.; Rozhansky, V.A.; Rozhdestvensky, V.V.; Tendler, M.; Tukachinsky, A.S.; Jaroshevich, S.P.

    1995-01-01

    The open-quote open-quote TUMAN-3 close-quote close-quote Tokamak programme concentrates on issues of improved confinement. In 1989 the transition from an ordinary Ohmic regime into an improved confinement mode was achieved. The signatures of the H-mode in auxiliary heated tokamaks have been observed in this regime. The crucial role of the boundary radial electric field was found in the experiments with internal bias probe. Other techniques were demonstrated to disturb the boundary plasma which led to H-mode triggering: short increase of working gas puffing, minor radius magnetic compression and pellet injection. The role scaling of the energy confinement time in the Ohmic H-mode was obtained, which differs dramatically from the scaling for the ordinary Ohmic regime. There were found a strong dependence of τ E on plasma current and a weak dependence on density. The maximum value of τ E was 10 times longer than in the ordinary Ohmic region. The τ E scaling for the Ohmic H-mode is consistent with the scaling proposed for devices with powerful auxiliary heating. The results shows that H-mode physics is universal in tokamaks with different geometries and heating methods. (AIP) copyright 1995 American Institute of Physics

  13. The ICRH tokamak fusion test reactor

    International Nuclear Information System (INIS)

    Perkins, F.W.

    1976-01-01

    A Tokamak Fusion Test Reactor where the ion are maintained at Tsub(i) approximately 20keV>Tsub(e) approximately 7keV by ion-cyclotron resonance heating is shown to produce an energy amplification of Q>2 provided the principal ion energy loss channel is via collisional transfer to the electrons. Such a reactor produces 19MW of fusion power to the electrons. Such a reactor produces 19MW of fusion power and requires a 50MHz radio-frequency generator capable of 50MW peak power; it is otherwise compatible with the conceptual design for the Princeton TFTR. The required n tausub(E) values for electrons and ions are respectively ntausub(Ee)>1.5.10 13 cm -3 -sec and ntausub(Ei)>4.10 13 cm -3 -sec. The principal areas where research is needed to establish this concept are: tokamak transport calculations, ICRH physics, trapped-particle instability energy losses, tokamak equilibria with high values of βsub(theta), and, of course, impurities

  14. On the density limit of Tokamaks

    International Nuclear Information System (INIS)

    Lehnert, B.

    1982-12-01

    Under the conditions of so far performed quasi-steady tokamak experiments near the density limit, the plasma pressure gradient in the outer layers of the plasma body becomes mainly determined by the plasma-neutral gas balance. An earlier analysis of ballooning instabilities driven by this gradient in regions of bad curvature has been extended to deduce an explicit stability criterion which determines the density limit. This criterion is closely related to the empirical Murakami limit. At relevant tokamak data, the deduced limit becomes proportional to J(sub)zR(sup)1/2 where J(sub)z is the average current density and R the major plasma radius. It is further found to be independent of the toroidal magnetic field strength and anomalous transport, as well as to be a slow function of the outer layer temperature and the mass number. The deduced stability criterion is consistent with so far performed experiments. Provided that the present analysis can be extrapolated to a wider range of parameter data and be combined with Alcator scaling, conditions near ignition appear to become realizable in small tokamaks by ohmic heating alone. These conditions can be satisfied at relevant magnetic field strengths and plasma currents, by imposing a high plasma current density. (author)

  15. Initial DEMO tokamak design configuration studies

    Energy Technology Data Exchange (ETDEWEB)

    Bachmann, Christian, E-mail: christian.bachmann@efda.org [EFDA, Boltzmannstraße 2, 85748 Garching (Germany); Aiello, G. [CEA-Saclay, DEN, DM2S, SEMT, F-91191 Gif-Sur-Yvette (France); Albanese, R.; Ambrosino, R. [ENEA/CREATE, Universita di Napoli Federico II, Naples (Italy); Arbeiter, F. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Aubert, J. [CEA-Saclay, DEN, DM2S, SEMT, F-91191 Gif-Sur-Yvette (France); Boccaccini, L.; Carloni, D. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Federici, G. [EFDA, Boltzmannstraße 2, 85748 Garching (Germany); Fischer, U. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Kovari, M. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Li Puma, A. [CEA-Saclay, DEN, DM2S, SEMT, F-91191 Gif-Sur-Yvette (France); Loving, A. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Maione, I. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Mattei, M. [ENEA/CREATE, Universita di Napoli Federico II, Naples (Italy); Mazzone, G. [ENEA C.R. Frascati, via E. Fermi 45, 00044 Frascati, Roma (Italy); Meszaros, B. [EFDA, Boltzmannstraße 2, 85748 Garching (Germany); Palermo, I. [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid (Spain); Pereslavtsev, P. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Riccardo, V. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); and others

    2015-10-15

    Highlights: • A definition of main DEMO requirements. • A description of the DEMO tokamak design configuration. • A description of issues yet to be solved. - Abstract: To prepare the DEMO conceptual design phase a number of physics and engineering assessments were carried out in recent years in the frame of EFDA concluding in an initial design configuration of a DEMO tokamak. This paper gives an insight into the identified engineering requirements and constraints and describes their impact on the selection of the technologies and design principles of the main tokamak components. The EU DEMO program aims at making best use of the technologies developed for ITER (e.g., magnets, vessel, cryostat, and to some degree also the divertor). However, other systems in particular the breeding blanket require design solutions and advanced technologies that will only partially be tested in ITER. The main differences from ITER include the requirement to breed, to extract, to process and to recycle the tritium needed for plasma operation, the two orders of magnitude larger lifetime neutron fluence, the consequent radiation dose levels, which limit remote maintenance options, and the requirement to use low-activation steel for in-vessel components that also must operate at high temperature for efficient energy conversion.

  16. The spheric tokamak programme at Culham

    International Nuclear Information System (INIS)

    Sykes, A.

    1999-01-01

    The Spherical Tokamak (ST) is the low aspect ratio limit of the conventional tokamak, and appears to offer attractive physics properties in a simpler device. The START (Small Tight Aspect Ratio Tokamak) experiment provided the world's first demonstration of the properties of hot plasmas in an ST configuration, and was operational at Culham from January 1991 to March 1998, obtaining plasma current of up to 300 kA and pulse durations of ∼ 50 ms. Its successor, MAST is scheduled to obtain first plasma in Autumn 1998 and is a purpose built, high vacuum machine designed to have a tenfold increase in plasma volume with plasma currents up to 2 MA. Current drive and heating will be by a combination of induction-compression as on START, a high-performance central solenoid, 1.5 MW ECRH and 5 MW of Neutral Beam Injection. The promising results from START are reviewed, and the many challenges posed for the next generation of purpose-built STs (such as MAST) are described. (author)

  17. Experimental and theoretical basis for advanced tokamaks

    International Nuclear Information System (INIS)

    Chan, V.S.

    1994-09-01

    In this paper, arguments will be presented to support the attractiveness of advanced tokamaks as fusion reactors. The premise that all improved confinement regimes obtained to date were limited by magnetohydrodynamic stability will be established from experimental results. Accessing the advanced tokamak regime, therefore, requires means to overcome and enhance the beta limit. We will describe a number of ideas involving control of the plasma internal profiles, e.g. to achieve this. These approaches will have to be compatible with the underlying mechanisms for confinement improvement, such as shear rotation suppression of turbulence. For steady-state, there is a trade-off between full bootstrap current operation and the ability to control current profiles. The coupling between current drive and stability dictates the choice of sources and suggests an optimum for the bootstrap fraction. We summarize by presenting the future plans of the US confinement devices, DIII-D, PBX-M, C-Mod, to address the advanced tokamak physics issues and provide a database for the design of next-generation experiments

  18. The design of the KSTAR tokamak

    International Nuclear Information System (INIS)

    Lee, G.S.; Kim, J.; Hwang, S.M.

    1999-01-01

    The Korea superconducting tokamak advanced research (KSTAR) project is the major effort of the Korean national fusion program (KNFP) to develop a steady-state-capable advanced superconducting tokamak to establish a scientific and technological basis for an attractive fusion reactor. Major parameters of the tokamak are: major radius 1.8 m, minor radius 0.5 m, toroidal field 3.5 Tesla, and plasma current 2 MA with a strongly shaped plasma cross-section and double-null divertor. The initial pulse length provided by the poloidal magnet system is 20 s, but the pulse length can be increased to 300 s through non-inductive current drive. The plasma heating and current drive system consists of neutral beam, ion cyclotron waves, lower hybrid waves, and electron-cyclotron waves for flexible profile control. A comprehensive set of diagnostics is planned for plasma control and performance evaluation and physics understanding. The project has completed its conceptual design phase and moved to the engineering design phase. The target date of the first plasma is set for year 2002. (orig.)

  19. Electron cyclotron emission from tokamak plasmas

    International Nuclear Information System (INIS)

    Sillen, R.M.J.

    1986-01-01

    Emitted electron radiation can be used as a diagnostic signal to measure the electron temperature of a thermonuclear plasma. This type of diagnostics is well established in tokamak physics. In ch. 2 of this thesis the development, calibration and special design features are treated of a six-channel prototype of a twelve-channel grating spectrometer which is built for JET at Culham for electron cyclotron emission (ECE) measurements. In order to test this prototype measurements have been performed with the T-10 tokamak at the Kurchatov Institute in Moscow. With this prototype nearly half of the temperature profile of the T-10 could be measured. Detailed observations of sawteeth instabilities have been performed. Plasma heating by electron cyclotron resonance heating experiments was studied. A detailed description of these measurements and results is given in ch. 3. Often ECE spectra from tokamaks showed non-thermal features. In order to interprete them a computer code Notec has been developed. This code that calculates the ECE radiation emerging from the plasma for a 3-D configuration, is described in ch. 4. Some preliminary results and applications are presented. (Auth.)

  20. Transesterification of triacetin and castor oil with methanol catalyzed by supported polyaniline-sulfate. A role of polymer morphology

    Czech Academy of Sciences Publication Activity Database

    Drelinkiewicz, A.; Kalemba-Jaje, Z.; Lalik, E.; Zieba, A.; Mucha, D.; Konyushenko, Elena; Stejskal, Jaroslav

    2013-01-01

    Roč. 455, 30 March (2013), s. 92-106 ISSN 0926-860X Institutional support: RVO:61389013 Keywords : transesterification * triacetin * castor oil Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.674, year: 2013

  1. Outbreaks of Chrysodeixis includens (Walker (Lepidoptera: Noctuidae in common bean and castor bean in São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Edson Luiz Lopes Baldin

    2014-12-01

    Full Text Available Since 2009, increasing populations of Chrysodeixis includens (Walker (Lepidoptera: Noctuidae have been observed in cultivated common bean (Phaseolus vulgaris L. and castor bean (Ricinus communis L. at the Lageado Experimental Farm, belonging to the FCA/UNESP, Botucatu, São Paulo State, Brazil. Defoliations around 80% and 50% were observed in the common bean cv. Pérola and castor bean cv. IAC-2028, respectively. Samples of individuals (caterpillars and pupae were collected in the field, and kept in laboratory until adult emergence aiming to confirm the species. These are new observations for common bean in São Paulo State and, in the case of castor bean, unpublished in Brazil. It suggests that C. includens has adapted to attack other agricultural crops, demanding attention of common bean and castor bean producers.

  2. The effect of herbivory on temporal and spatial dynamics of foliar nectar production in cotton and castor

    NARCIS (Netherlands)

    Wäckers, F.L.; Zuber, D.; Wunderlin, R.; Keller, F.

    2001-01-01

    The effects of feeding Spodoptera a littoralis (Boisd.) (Lepidoptera: Noctuidae) larvae on the quantity and distribution of extrafloral nectar production by leaves of castor ((Ricinus communis) and cotton (Gossypium herbaceum) were investigated. Following larval feeding, the total volume of nectar

  3. The effect of herbivory on temporal and spatial dynamics of foliar nectar production in cotton and castor

    NARCIS (Netherlands)

    Wäckers, F.L.; Zuber, D.; Wunderlin, R.; Keller, F.

    2001-01-01

    The effects of feeding Spodoptera littoralis(Boisd.) (Lepidoptera: Noctuidae) larvae on the quantity and distribution of extrafloral nectar production by leaves of castor (Ricinus communis) and cotton (Gossypium herbaceum) were investigated. Following larval feeding, the total volume of nectar

  4. Deposit of thin films for Tokamaks conditioning

    International Nuclear Information System (INIS)

    Valencia A, R.

    2006-01-01

    As a main objective of this work, we present some experimental results obtained from studying the process of extracting those impurities created by the interaction plasma with its vessel wall in the case of Novillo tokamak. Likewise, we describe the main cleaning and conditioning techniques applied to it, fundamentally that of glow discharge cleaning at a low electron temperature ( -6 to 4.5 x 10 -6 Ω-m, thus taking the Z ef value from 3.46 to 2.07 which considerably improved the operational parameters of the machine. With a view to justifying the fact that controlled nuclear fusion is a feasible alternative for the energy demand that humanity will face in the future, we review in Chapter 1 some fundamentals of the energy production by nuclear fusion reactions while, in Chapter 2, we examine two relevant plasma wall interaction processes. Our experimental array used to produce both cleaning and intense plasma discharges is described in Chapter 3 along with the associated diagnostics equipment. Chapter 4 contains a description of the vessel conditioning techniques followed in the process. Finally, we report our results in Chapter 5 while, in Chapter 6, some conclusions and remarks are presented. It is widely known that tokamak impurities are generated mainly by the plasma-wall interaction, particularly in the presence of high potentials between the plasma sheath and the limiter or wall. Given that impurities affect most adversely the plasma behaviour, understanding and controlling the impurity extraction mechanisms is crucial for optimizing the cleaning and wall conditioning discharge processes. Our study of one impurity extraction mechanism for both low and high Z in Novillo tokamak was carried out though mass spectrometry, optical emission spectroscopy and plasma resistivity measurement. Such mechanism depends fundamentally on the mass of the ions that interact with the wall during the plasma current formation phase. The reaction products generated by the glow

  5. Long-acting poly(DL:lactic acid-castor oil) 3:7-bupivacaine formulation: effect of hydrophobic additives.

    Science.gov (United States)

    Sokolsky-Papkov, Marina; Golovanevski, Ludmila; Domb, Abraham J; Weiniger, Carolyn F

    2011-12-01

    To reduce formulation viscosity of bupivacaine/poly(DL lactic acid co castor oil) 3:7 without increasing bupivacaine release rates. Poly(DL lactic acid) 3:7 was synthesized and bupivacaine formulation prepared by mixing with additives ricinoleic acid or castor oil. In vitro release measurements identified optimum formulation. Anesthetized ICR mice were injected around left sciatic nerve using nerve stimulator with 0.1 mL of formulation. Animals received 10% bupivacaine-polymer formulation with 10% castor oil (p(DLLA:CO)3:7-10% bupi-10% CO) or 15% bupivacaine-polymer with 10% castor oil (p(DLLA:CO)3:7-15% bupi-10% CO). Sensory and motor block were measured. Viscosity of 10% and 15% bupivacaine-p(DLLA:CO)3:7 formulations was reduced using hydrophobic additives; however, castor oil reduced bupivacaine release rates and eliminated burst effect. Less than 10% of the incorporated bupivacaine was released during 6 h, and less than 25% released in 24 h in vitro. In vivo formulation injection resulted in a 24 h motor block and a sensory block lasting at least 72 h. Incorporation of hydrophobic low-viscosity additive reduced viscosity in addition to burst release effects. Bupivacaine-polymer formulation with castor oil additive demonstrated prolonged sensory analgesia in vivo, with reduced duration of motor block.

  6. Efficiency of Castor Oil as a Storage Medium for Avulsed Teeth in Maintaining the Viability of Periodontal Ligament Cells.

    Science.gov (United States)

    Nabavizadeh, Mohammadreza; Abbaszadegan, Abbas; Khodabakhsi, Afrooz; Ahzan, Shamseddin; Mehrabani, Davood

    2018-03-01

    Researchers always seek a new storage medium for avulsed teeth. Castor oil is a vegetable oil with several advantages such as antimicrobial and antioxidant properties, low toxicity, and glutathione preservation capability, low cost, and high availability. The purpose of this study was to evaluate and compare the capacity of castor oil as a new storage medium in preserving the viability of periodontal ligament (PDL) cells compared to Hank's balanced salt solution (HBSS) and milk. Forty freshly extracted human teeth were divided into 3 experimental and 2 control groups. The experimental teeth were stored dry for 30 min and then immersed for 45 min in one of the following media; castor oil, HBSS, and milk. The positive and negative control groups were exposed to 0 min and 2 h of dry time respectively with no immersion in any storage medium. The teeth were then treated with dispase grade II and collagenase and the number of viable PDL cells were counted. Data were analyzed using Kruskal- Wallis test. The percentage of viable cells treated with castor oil, HBSS and milk counted immediately after removal from these media were 46.93, 51.02 and 55.10 % respectively. The statistical analysis revealed that the value for castor oil was significantly lower than HBSS and milk ( p > 0.05). Within the parameters of this study, it appears that castor oil cannot be served as an ideal medium for storage of avulsed tooth. More investigations under in vivo conditions are required to justify the results of this study.

  7. Fatty acid methyl esters (FAMEs) from castor oil: Production process assessment and synergistic effects in its properties

    Energy Technology Data Exchange (ETDEWEB)

    Canoira, Laureano; Garcia Galean, Juan; Alcantara, Ramon [Department of Chemical Engineering and Fuels, ETS Ingenieros de Minas, Universidad Politecnica de Madrid, Rios Rosas 21, 28003 Madrid (Spain); Lapuerta, Magin; Garcia-Contreras, Reyes [Maquinas y Motores Termicos, ETS Ingenieros Industriales, Universidad de Castilla La Mancha, Avda. Camilo Jose Cela s/n, 13071 Ciudad Real (Spain)

    2010-01-15

    Fatty acid methyl esters (FAMEs) from castor oil have been synthesized by methanolysis catalyzed by sodium methoxide and the optimal transesterification conditions have been found. However, some properties of the castor FAME render it unsuitable in pure state for its direct use as fuel in internal combustion engines. Thus, blends with reference diesel have been prepared and their properties have been evaluated. Among these properties, the oxidative stability of the blends shows a negative anti-synergistic effect, that is, all the blends have an induction period lower than the pure reference diesel and the pure castor FAME. On the contrary, the lubricity shows a positive synergistic effect, the wear scar of the blends being always lower than those of the pure components. The cold-filter plugging point of the blends shows also a singular effect, since the filterability remains identical to that of the reference diesel until around 50 vol% of castor FAME has been blended with it. The blends of castor FAME and reference diesel until approximately 40 vol% of castor FAME meet most of the specifications of the EN 590 standard. (author)

  8. Mit castor satellite: Design, implementation, and testing of the communication system

    Science.gov (United States)

    Babuscia, Alessandra; McCormack, Matthew Michael; Munoz, Michael; Parra, Spencer; Miller, David W.

    2012-12-01

    Cathode Anode Satellite Thruster for Orbital Reposition (CASTOR) is an orbital manoeuvre and transfer micro-satellite bus developed at MIT Space System Laboratory. The technical objective of the mission is achieving 1 km/s of delta-V over a 1 year mission in Low Earth Orbit (LEO). This will be accomplished using a novel electric propulsion system, the Diverging Cusped Field Thruster (DCFT), which enables high efficiency orbital changes of the ESPA-ring class satellite. CASTOR is capable of improving rapid access to space capabilities by providing an orbital transfer platform with a very high performance to mass ratio, thus greatly reducing launch costs and allowing for highly efficient orbital manoeuvre. Furthermore, CASTOR is highly scalable and modular, allowing it to be adapted to a wide range of scales and applications. CASTOR is developed as part of the University Nanosatellite Program (UNP) funded by Air Force Research Laboratory (AFRL). In order to accomplish CASTOR mission objective, a highly optimized, scalable, light weight, and low cost communication system needed to be developed. These constraints imply the development of trade studies to select the final communication system architecture able to maximize the amount of data transmitted, while guaranteeing reliability, redundancy and limited mass, power consumption, and cost. A special attention is also required to guarantee a reliable communication system in cases of tumbling, or in case of strong Doppler shift which is inevitable due to the high delta-V capabilities of the vehicle. In order to accomplish all the mission requirements, different features have been introduced in the design of the communication system for this mission. Specifically, customized patch antennas have been realized, and a customized communication protocol has been designed and implemented. The communication subsystem has been validated through an intense testing campaign which included software tests in the laboratory, hardware

  9. Toroidal and poloidal momentum transport studies in Tokamaks

    DEFF Research Database (Denmark)

    Tala, T.; Andrew, Y.; Giroud, C.

    2007-01-01

    The present status of understanding of toroidal and poloidal momentum transport in tokamaks is presented in this paper. Similar energy confinement and momentum confinement times, i.e. τE/τφ ≈ 1 have been reported on several tokamaks. It is more important though, to study the local transport both ...

  10. Design and construction of electronic components for a ''Novillo'' Tokamak

    International Nuclear Information System (INIS)

    Lopez C, R.

    1986-07-01

    The goal of this effort was to design, construct and make functional the electronic components for a ''Novillo'' Tokamak currently being experimentally investigated at the National Institute of Nuclear Research in Mexico. The problem was to develop programmable electronic switches capable of discharging high voltage kilowatt energies stored in capacitator banks onto the coils of the Tokamak. (author)

  11. Physics design requirements for the Tokamak Physics Experiment (TPX)

    International Nuclear Information System (INIS)

    Neilson, G.H.; Goldston, R.J.; Jardin, S.C.; Reiersen, W.T.; Porkolab, M.; Ulrickson, M.

    1993-01-01

    The design of TPX is driven by physics requirements that follow from its mission. The tokamak and heating systems provide the performance and profile controls needed to study advanced steady state tokamak operating modes. The magnetic control systems provide substantial flexibility for the study of regimes with high beta and bootstrap current. The divertor is designed for high steady state power and particle exhaust

  12. Magnetohydrodynamic Waves and Instabilities in Rotating Tokamak Plasmas

    NARCIS (Netherlands)

    J.W. Haverkort (Willem)

    2013-01-01

    htmlabstractOne of the most promising ways to achieve controlled nuclear fusion for the commercial production of energy is the tokamak design. In such a device, a hot plasma is confined in a toroidal geometry using magnetic fields. The present generation of tokamaks shows significant plasma

  13. Lower hybrid heating experiments in tokamaks: an overview

    International Nuclear Information System (INIS)

    Porkolab, M.

    1985-10-01

    Lower hybrid wave propagation theory relevant to heating fusion grade plasmas (tokamaks) is reviewed. A brief discussion of accessibility, absorption, and toroidal ray propagation is given. The main part of the paper reviews recent results in heating experiments on tokamaks. Both electron and ion heating regimes will be discussed. The prospects of heating to high temperatures in reactor grade plasmas will be evaluated

  14. Tokamak Plasmas: Measurement of temperature fluctuations and ...

    Indian Academy of Sciences (India)

    ... Refresher Courses · Symposia · Live Streaming. Home; Journals; Pramana – Journal of Physics; Volume 55; Issue 5-6. Tokamak Plasmas : Measurement of temperature fluctuations and anomalous transport in the SINP tokamak. R Kumar S K Saha. Contributed Papers Volume 55 Issue 5-6 November-December 2000 pp ...

  15. Recent progress on the Compact Ignition Tokamak (CIT)

    International Nuclear Information System (INIS)

    Ignat, D.W.

    1987-01-01

    This report describes work done on the Compact Ignition Tokamak (CIT), both at the Princeton Plasma Physics Laboratory (PPPL) and at other fusion laboratories in the United States. The goal of CIT is to reach ignition in a tokamak fusion device in the mid-1990's. Scientific and engineering features of the design are described, as well as projected cost and schedule

  16. The physics of magnetic confinement configurations : Tokamak theory and experiment

    International Nuclear Information System (INIS)

    Robinson, D.C.

    1982-01-01

    Several aspects, both theoretical and experimental, in plasma physics are discussed. The problem of magnetic confinement in Tokamak devices is treated. A discussion on the history of the development and on the future problems to be solved in Tokamaks is made. (L.C.) [pt

  17. Tokamak WEST připraven ke startu!

    Czech Academy of Sciences Publication Activity Database

    Řípa, Milan

    Květen (2017) ISSN 2464-7888 Institutional support: RVO:61389021 Keywords : fusion * ITER * tokamak * WEST * Tora Supra * divertor Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) http://www.3pol.cz/cz/rubriky/jaderna-fyzika-a-energetika/2014-tokamak-west-pripraven-ke- start u

  18. Control strategy for plasma equilibrium in a tokamak

    International Nuclear Information System (INIS)

    Miskell, R.V.

    1975-08-01

    Dynamic control of the plasma position within the torus of a TOKAMAK fusion device is a significant factor in the development of nuclear fusion as an energy source. This investigation develops a state variable model of a TOKAMAK thermonuclear device, suitable for application of modern control theory techniques. (auth)

  19. Toroidal and poloidal momentum transport studies in tokamaks

    DEFF Research Database (Denmark)

    Tala, T.; Crombé, K.; Vries, P.C. de

    2007-01-01

    The present status of understanding of toroidal and poloidal momentum transport in tokamaks is presented in this paper. Similar energy confinement and momentum confinement times, i.e. τE/τφ ≈ 1 have been reported on several tokamaks. It is more important though, to study the local transport both ...

  20. System assessment of helical reactors in comparison with tokamaks

    International Nuclear Information System (INIS)

    Yamazaki, K.; Imagawa, S.; Muroga, T.; Sagara, A.; Okamura, S.

    2002-01-01

    A comparative assessment of tokamak and helical reactors has been performed using equivalent physics/engineering model and common costing model. Higher-temperature plasma operation is required in tokamak reactors to increase bootstrap current fraction and to reduce current-drive (CD) power. In helical systems, lower-temperature operation is feasible and desirable to reduce helical ripple transport. The capital cost of helical reactor is rather high, however, the cost of electricity (COE) is almost same as that of tokamak reactor because of smaller re-circulation power (no CD power) and less-frequent blanket replacement (lower neutron wall loading). The standard LHD-type helical reactor with 5% beta value is economically equivalent to the standard tokamak with 3% beta. The COE of lower-aspect ratio helical reactor is on the same level of high-β N tokamak reactors. (author)

  1. Exploiting EST databases for the development and characterization of EST-SSR markers in castor bean (Ricinus communis L.

    Directory of Open Access Journals (Sweden)

    Yang Jun-Bo

    2010-12-01

    Full Text Available Abstract Background The castor bean (Ricinus communis L., a monotypic species in the spurge family (Euphorbiaceae, 2n = 20, is an important non-edible oilseed crop widely cultivated in tropical, sub-tropical and temperate countries for its high economic value. Because of the high level of ricinoleic acid (over 85% in its seed oil, the castor bean seed derivatives are often used in aviation oil, lubricants, nylon, dyes, inks, soaps, adhesive and biodiesel. Due to lack of efficient molecular markers, little is known about the population genetic diversity and the genetic relationships among castor bean germplasm. Efficient and robust molecular markers are increasingly needed for breeding and improving varieties in castor bean. The advent of modern genomics has produced large amounts of publicly available DNA sequence data. In particular, expressed sequence tags (ESTs provide valuable resources to develop gene-associated SSR markers. Results In total, 18,928 publicly available non-redundant castor bean EST sequences, representing approximately 17.03 Mb, were evaluated and 7732 SSR sites in 5,122 ESTs were identified by data mining. Castor bean exhibited considerably high frequency of EST-SSRs. We developed and characterized 118 polymorphic EST-SSR markers from 379 primer pairs flanking repeats by screening 24 castor bean samples collected from different countries. A total of 350 alleles were identified from 118 polymorphic SSR loci, ranging from 2-6 per locus (A with an average of 2.97. The EST-SSR markers developed displayed moderate gene diversity (He with an average of 0.41. Genetic relationships among 24 germplasms were investigated using the genotypes of 350 alleles, showing geographic pattern of genotypes across genetic diversity centers of castor bean. Conclusion Castor bean EST sequences exhibited considerably high frequency of SSR sites, and were rich resources for developing EST-SSR markers. These EST-SSR markers would be particularly

  2. Radiation protection during the loading of Castor MTR 2 at VKTA

    International Nuclear Information System (INIS)

    Kowe, S.; Sahre, P.; Boessert, W.

    2001-01-01

    During the dry loading of spent fuel elements from the storage pool AB 2 into the CASTOR MTR 2 using the mobile loading station radiation protection surveillance has been carried out by the reactor crew as well as by the dosimetry and incorporation surveillance group. First of all there was an training of the loading without any activity. The resulting experiences influenced the radiation protection programme. Furthermore incorporation monitoring of all involved persons before, during and after the loading were carried out. The results confirm which was expected from the dry loading technology. Of course there was an permanent radiation monitoring during the loading. From the permanently measured air activity concentration no emission or incorporation were expected. Dose rate measurements at the transfer unit CAeSAR III and the CASTOR MTR 2 leads to the detection of non expected radiation gaps. This results in corresponding measures in order to optimise radiation exposure. (orig.) [de

  3. Analysis of quality of the biogasoils of palm oil and castor oil

    International Nuclear Information System (INIS)

    Benjumea, Pedro Nel; Agudelo, Jhon Ramiro; Benavides, Alirio Yovany

    2004-01-01

    Biodiesel is a fuel made from raw materials of renewable origin such as vegetable oils. The objective of this work is to make a quality analysis of two types of biodiesel made from raw materials available in Colombia such as palm oil and castor oil. Biodiesel from palm oil complies with the majority of technical requirements specified by ASTM standards D-975 y D-6751. A high cloud point is the main drawback of this kind of biodiesel. This is a consequence of its highly saturated chemical nature. On the other hand, biodiesel from castor oil presents more difficulties in order to be used in diesel engines because of having a low cetane index and a high viscosity

  4. Low density polyethylene (LDPE) / poli (3-hydroxy-butyrate) (PHB) blends filled with castor oil cake

    International Nuclear Information System (INIS)

    Rocha, M.C.G.; Oliveira, C.I.R. de; Sanches, M.C.; Coelho, N.N.

    2014-01-01

    Blends of PHB and LDPE were prepared by melt mixing in a Haake internal mixer. Castor oil pressed cake was used as filler for the blends. In order to improve the interfacial adhesion between the filler and the polymers, a mercerization process with 5% NaOH solution was employed. This process was evaluated by several techniques such as: X-Ray diffraction, infrared spectroscopy and scanning electron microscopy (SEM). The mechanical properties were evaluated by traditional tensile stress-strain tests (ASTM D- 638). The obtained results showed that the mercerization process leads to better adhesion properties. The Young Modulus of the blends presented a tendency to increase with the addition of the castor oil cake.(author)

  5. Biodiesel production from castor oil using heterogeneous Ni doped ZnO nanocatalyst.

    Science.gov (United States)

    Baskar, G; Aberna Ebenezer Selvakumari, I; Aiswarya, R

    2018-02-01

    In the present study, castor oil with high free fatty acid was used for biodiesel production using heterogeneous Ni doped ZnO nanocatalyst. Ni doped ZnO nanocomposite calcinated at 800 °C has shown better catalytic activity. Process parameters on heterogeneous catalysis of castor oil into biodiesel were optimized using conventional and Response Surface Methodology (RSM). RSM was found more accurate in estimating the optimum conditions with higher biodiesel yield (95.20%). The optimum conditions for transesterification was found to be oil to methanol molar ratio of 1:8, catalyst loading 11% (w/w), reaction temperature of 55 °C for 60 min of reaction time by response surface method. The reusability studies showed that the nanocatalyst can be reused efficiently for 3 cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Production and characterization of MDF using eucalyptus fibers and castor oil-based polyurethane resin

    Directory of Open Access Journals (Sweden)

    Campos Cristiane Inácio de

    2004-01-01

    Full Text Available The growing popularity of wooden panels renders this market segment increasingly competitive. MDF (Medium Density Fiberboard, in particular, is widely employed for a variety of applications, including civil construction, furniture, and packaging. This paper discusses a study of MDF produced from alternative raw materials, i.e., Eucalyptus fibers and castor-oil-based polyurethane resin. Physical and mechanical tests were performed to determine the MDF's modulus of elasticity and modulus of rupture in static bending tests, its swelling, water absorption, moisture and density. The results of the physical and mechanical characterization of this laboratory-produced MDF are discussed and compared with the Euro MDF Board standard. MDF produced with eucalyptus fiber and castor-oil-based polyurethane resin presents results very satisfactory.

  7. Life cycle assessment of castor-based biorefinery: a well to wheel LCA

    DEFF Research Database (Denmark)

    Khoshnevisan, Benyamin; Rafiee, Shahin; Tabatabaei, Meisam

    2017-01-01

    also considered as byproducts. Developed scenarios were also compared with a fossil reference system delivering the same amount of energy through the combustion of neat diesel. Materials and methods: Life cycle assessment (LCA) was used to investigate the environmental consequences of castor biodiesel...... of their ability in converting biomass into a spectrum of marketable products and bioenergies. This study was aimed at developing different novel castor-based biorefinery scenarios for generating biodiesel and other co-products, i.e., ethanol and biogas. In these scenarios, glycerin, heat, and electricity were...... production and consumption with a biorefinery approach. All the input and output flows from the cultivation stage to the combustion in diesel engines as well as changes in soil organic carbon (SOC) were taken into account. Impact 2002+ method was used to quantify the environmental consequences. Results...

  8. The physics of an ignited tokamak

    International Nuclear Information System (INIS)

    Troyon, F.

    1990-10-01

    There appears to be a consensus that time has come to embark on the design and construction of the next generation of tokamaks which is at the origin of the ITER initiative. Different proposals have been made based on different appreciation as to the size of the step which can be taken, related to considerations of cost, risk and duration of construction. A class of devices which may be considered the last the very high-field, high density ALCATOR-Frascati line of tokamaks have been proposed for some years specifically for this purpose. Today there remain three such projects: Ignitor, Ignitex and CIT. The technology chosen limits the pulse length to a few seconds. These devices have evolved through the years becoming larger and much more expensive than originally anticipated, increasing the pressure to do more than just a simple demonstration of ignition. There is another class of more ambitious devices which aim at creating long burning plasmas in conditions as close as possible to those of a tokamak reactor in order to address all the plasma physics problems associated with long burn. Three such projects, NET, the european next step after JET, ITER and JIT are good examples of this approach. The ideal would be to design a device with sufficient margin to study burning plasmas over a wide range of parameters. The object of this didactic presentation is to describe the common physics basis of all these projects, compare their expected performance using present knowledge and list the physics problems associated with a burning plasma experiment. The comparison is not meant to be a judgement since the important parameter is the cost/benefit ratio which is a matter of appreciation at this stage. 6 refs., 3 figs., 1 tab

  9. Mathematical modeling plasma transport in tokamaks

    International Nuclear Information System (INIS)

    Quiang, Ji

    1995-01-01

    In this work, the author applied a systematic calibration, validation and application procedure based on the methodology of mathematical modeling to international thermonuclear experimental reactor (ITER) ignition studies. The multi-mode plasma transport model used here includes a linear combination of drift wave branch and ballooning branch instabilities with two a priori uncertain constants to account for anomalous plasma transport in tokamaks. A Bayesian parameter estimation method is used including experimental calibration error/model offsets and error bar rescaling factors to determine the two uncertain constants in the transport model with quantitative confidence level estimates for the calibrated parameters, which gives two saturation levels of instabilities. This method is first tested using a gyroBohm multi-mode transport model with a pair of DIII-D discharge experimental data, and then applied to calibrating a nominal multi-mode transport model against a broad database using twelve discharges from seven different tokamaks. The calibrated transport model is then validated on five discharges from JT-60 with no adjustable constants. The results are in a good agreement with experimental data. Finally, the resulting class of multi-mode tokamak plasma transport models is applied to the transport analysis of the ignition probability in a next generation machine, ITER. A reference simulation of basic ITER engineering design activity (EDA) parameters shows that a self-sustained thermonuclear burn with 1.5 GW output power can be achieved provided that impurity control makes radiative losses sufficiently small at an average plasma density of 1.2 X 10 20 /m 3 with 50 MW auxiliary heating. The ignition probability of ITER for the EDA parameters, can be formally as high as 99.9% in the present context. The same probability for concept design activity (CDA) parameters of ITER, which has smaller size and lower current, is only 62.6%

  10. Evaluation of Castor Bark Powder as a Corrosion Inhibitor for Carbon Steel in Acidic Media

    OpenAIRE

    Santos, André de Mendonça; Almeida, Thassia Felix de; Cotting, Fernando; Aoki, Idalina Vieira; Melo, Hercílio Gomes de; Capelossi, Vera Rosa

    2017-01-01

    The inhibition effect of castor bark powder obtained from Ricinus communis on AISI 1020 carbon steel in acidic media (HCl 0.5 mol.L-1) has been studied by electrochemical impedance spectroscopy (EIS), polarization curves, scanning vibrating electrode technique (SVET) and weight loss measurements. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed as characterization techniques. The EIS and gravimetric results showed that the inhibitory efficien...

  11. Hybrid vigour and gene action for two quantitative traits of castor ...

    African Journals Online (AJOL)

    Five homozygous lines of castor plant, namely RS1-Om, RN1-Om, RTl-2m, RSl- Owm, and RNl- Omb, were crossed to raise F1, F2, BC1, and BC2 generations. The hybrids were tested for hybrid vigour for two metric traits, viz; number of pods per plant and seed yield per plant. Highly significant hybrid vigour was detected ...

  12. Simultaneous allergen inactivation and detoxification of castor bean cake by treatment with calcium compounds.

    Science.gov (United States)

    Fernandes, K V; Deus-de-Oliveira, N; Godoy, M G; Guimarães, Z A S; Nascimento, V V; Melo, E J T de; Freire, D M G; Dansa-Petretski, M; Machado, O L T

    2012-11-01

    Ricinus communis L. is of great economic importance due to the oil extracted from its seeds. Castor oil has been used for pharmaceutical and industrial applications, as a lubricant or coating agent, as a component of plastic products, as a fungicide or in the synthesis of biodiesel fuels. After oil extraction, a castor cake with a large amount of protein is obtained. However, this by-product cannot be used as animal feed due to the presence of toxic (ricin) and allergenic (2S albumin) proteins. Here, we propose two processes for detoxification and allergen inactivation of the castor cake. In addition, we establish a biological test to detect ricin and validate these detoxification processes. In this test, Vero cells were treated with ricin, and cell death was assessed by cell counting and measurement of lactate dehydrogenase activity. The limit of detection of the Vero cell assay was 10 ng/mL using a concentration of 1.6 x 10(5) cells/well. Solid-state fermentation (SSF) and treatment with calcium compounds were used as cake detoxification processes. For SSF, Aspergillus niger was grown using a castor cake as a substrate, and this cake was analyzed after 24, 48, 72, and 96 h of SSF. Ricin was eliminated after 24 h of SSF treatment. The cake was treated with 4 or 8% Ca(OH)2 or CaO, and both the toxicity and the allergenic properties were entirely abolished. A by-product free of toxicity and allergens was obtained.

  13. Glutathione Preservation during Storage of Rat Lenses in Optisol-GS and Castor Oil

    DEFF Research Database (Denmark)

    Holm, Thomas; Brøgger-Jensen, Martin Rocho; Johnson, Leif

    2013-01-01

    Glutathione concentration in the lens decreases in aging and cataractous lenses, providing a marker for tissue condition. Experimental procedures requiring unfrozen lenses from donor banks rely on transportation in storage medium, affecting lens homeostasis and alterations in glutathione levels. ....... The aim of the study was to examine the effects of Optisol-GS and castor oil on lens condition, determined from their ability to maintain glutathione concentrations....

  14. Antimicrobial action of sodium hypochlorite and castor oil solutions for denture cleaning – in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Marcela Moreira SALLES

    2015-01-01

    Full Text Available The objective of this in vitro study was to evaluate the antimicrobial action of sodium hypochlorite (0.25% and 0.50% and 10% castor oil solutions against specific microorganisms, by counting Colony Forming Units (CFU of clinically important bacteria and Candida species. Acrylic resin specimens (n = 320; Lucitone 550 were obtained from square metal matrices (10 x 10 x 2 mm, sterilized by microwave (650W, for 6 minutes and contaminated by Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Bacillus subtilis, Escherichia coli, Streptococcus mutans, Enterococcus faecalisand Candida glabrata. The specimens were immersed for 20 minutes in one of the following hygiene solutions (n = 10/each: A – 0.25% Sodium hypochlorite; B – 0.5% Sodium hypochlorite; C – 10% Castor oil solution; and D (Control – saline. Adhered cells were suspended and inoculated into a selective solid medium (37ºC for 24 h. The Student’s t-test (α = 0.05 was performed to compare log10(CFU+1/mL between Groups C and D. The results showed that sodium hypochlorite (0.25% and 0.5% completely eliminated all detectable microorganisms. The castor oil solution eliminatedB. subtilisand reduced counts for other strains. Differences between C and D were significant (p E. faecalis. Both sodium hypochlorite solutions (0.25% and 0.5% were effective in eliminating all microorganisms evaluated, and may be useful as cleaning solutions for complete dentures. The castor oil solution provided moderate efficacy and performed differently on the tested species, with the strongest effect on B. subtilis and with non-significant action on E. faecalis.

  15. Cadmium sulfide quantum dots stabilized by castor oil and ricinoleic acid

    Science.gov (United States)

    Kyobe, Joseph William; Mubofu, Egid Beatus; Makame, Yahya M. M.; Mlowe, Sixberth; Revaprasadu, Neerish

    2016-02-01

    Castor oil and ricinoleic acid (an isolate of castor oil) are environmentally friendly bio-based organic surfactants that have been used as capping agents to prepare nearly spherical cadmium sulfide quantum dots (QDs) at 230, 250 and 280 °C. The prepared quantum dots were characterized by Ultra violet-visible (UV-vis), Photoluminescence (PL), Transmission Electron Microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM) and X-ray diffraction (XRD) giving an overall CdS QDs average size of 5.14±0.39 nm. The broad XRD pattern and crystal lattice fringes in the HRTEM images showed a hexagonal phase composition of the CdS QDs. The calculated/estimated average size of the prepared castor oil capped CdS QDs for various techniques were 4.64 nm (TEM), 4.65 nm (EMA), 5.35 nm (UV-vis) and 6.46 nm (XRD). For ricinoleic acid capped CdS QDs, the average sizes were 5.56 nm (TEM), 4.78 nm (EMA), 5.52 nm (UV-vis) and 8.21 nm (XRD). Optical properties of CdS QDs showed a change of band gap energy from its bulk band gap of 2.42-2.82 eV due to quantum size confinement effect for temperature range of 230-280 °C. Similarly, a blue shift was observed in the photoluminescence spectra. Scanning electron microscope (SEM) observations show that the as-synthesized CdS QDs structures are spherical in shape. Fourier transform infra-red (FTIR) studies confirms the formation of castor oil and ricinoleic acid capped CdS QDs.

  16. Nanoparticle Structures with (Un-)Hydrogenated Castor Oil as Hydrophobic Paper Coating.

    Science.gov (United States)

    Samyn, Pieter; Vonck, Leo; Stanssens, Dirk; Abbeele, Henk Van den

    2018-05-01

    The encapsulation of vegetable oils within an aqueous dispersion of polymer nanoparticles provides an alternative route to create functional paper coatings from renewable resources, by combining the presentation of hydrophobic moieties together with variations in roughness at the paper surface. The effects of two selected vegetable oil types, i.e., castor oil and hydrogenated castor oil (wax), are compared in terms of nanoparticle synthesis, coating hydrophobicity and surface gloss. The nanoparticles were synthesized by adding 50 wt.-% oil during imidization of poly(styrene-co-maleic anhydride) with ammonium hydroxide. From evaluation of the thermal properties, the nanoparticles have a high glass transition temperature that is suppressed in presence of oil. The nanoparticles with hydrogenated castor oil have higher imide content and better thermal stability compared to castor oil, in parallel with lower chemical reactivity of the hydrogenated oil and less interference with the imidization reaction. After deposition as a coating on paper, the physical coating properties are discussed in parallel with the coating chemistry and morphology or roughness at different scale lengths. The nanoparticle coatings with hydrogenated oil provides a multi-scale roughness with an open, porous nanoparticles structures and presentation of some amount free oil augmenting hydrophobicity towards a water contact angle of 128° (static contact angle) or 138° (advancing contact angle). The differences in surface coverage of coated papers in terms of imide and oil contents are confirmed by chemical Raman mapping. The differences in surface roughness are confirmed by non-contact profilometry, laser interferometry and atomic force microscopy.

  17. Simultaneous allergen inactivation and detoxification of castor bean cake by treatment with calcium compounds

    Directory of Open Access Journals (Sweden)

    K.V. Fernandes

    2012-11-01

    Full Text Available Ricinus communis L. is of great economic importance due to the oil extracted from its seeds. Castor oil has been used for pharmaceutical and industrial applications, as a lubricant or coating agent, as a component of plastic products, as a fungicide or in the synthesis of biodiesel fuels. After oil extraction, a castor cake with a large amount of protein is obtained. However, this by-product cannot be used as animal feed due to the presence of toxic (ricin and allergenic (2S albumin proteins. Here, we propose two processes for detoxification and allergen inactivation of the castor cake. In addition, we establish a biological test to detect ricin and validate these detoxification processes. In this test, Vero cells were treated with ricin, and cell death was assessed by cell counting and measurement of lactate dehydrogenase activity. The limit of detection of the Vero cell assay was 10 ng/mL using a concentration of 1.6 x 10(5 cells/well. Solid-state fermentation (SSF and treatment with calcium compounds were used as cake detoxification processes. For SSF, Aspergillus niger was grown using a castor cake as a substrate, and this cake was analyzed after 24, 48, 72, and 96 h of SSF. Ricin was eliminated after 24 h of SSF treatment. The cake was treated with 4 or 8% Ca(OH2 or CaO, and both the toxicity and the allergenic properties were entirely abolished. A by-product free of toxicity and allergens was obtained.

  18. Simultaneous allergen inactivation and detoxification of castor bean cake by treatment with calcium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, K.V.; Deus-de-Oliveira, N. [Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Rio de Janeiro, RJ (Brazil); Godoy, M.G. [Laboratório de Biotecnologia Microbiana, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Guimarães, Z.A.S. [Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Rio de Janeiro, RJ (Brazil); Nascimento, V.V. [Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Rio de Janeiro, RJ (Brazil); Melo, E.J.T. de [Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Rio de Janeiro, RJ (Brazil); Freire, D.M.G. [Laboratório de Biotecnologia Microbiana, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Dansa-Petretski, M.; Machado, O.L.T. [Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Rio de Janeiro, RJ (Brazil)

    2012-08-24

    Ricinus communis L. is of great economic importance due to the oil extracted from its seeds. Castor oil has been used for pharmaceutical and industrial applications, as a lubricant or coating agent, as a component of plastic products, as a fungicide or in the synthesis of biodiesel fuels. After oil extraction, a castor cake with a large amount of protein is obtained. However, this by-product cannot be used as animal feed due to the presence of toxic (ricin) and allergenic (2S albumin) proteins. Here, we propose two processes for detoxification and allergen inactivation of the castor cake. In addition, we establish a biological test to detect ricin and validate these detoxification processes. In this test, Vero cells were treated with ricin, and cell death was assessed by cell counting and measurement of lactate dehydrogenase activity. The limit of detection of the Vero cell assay was 10 ng/mL using a concentration of 1.6 × 10{sup 5} cells/well. Solid-state fermentation (SSF) and treatment with calcium compounds were used as cake detoxification processes. For SSF, Aspergillus niger was grown using a castor cake as a substrate, and this cake was analyzed after 24, 48, 72, and 96 h of SSF. Ricin was eliminated after 24 h of SSF treatment. The cake was treated with 4 or 8% Ca(OH){sub 2} or CaO, and both the toxicity and the allergenic properties were entirely abolished. A by-product free of toxicity and allergens was obtained.

  19. Characterization and Digestibility of Detoxified Castor Oil Meal for Japanese Quails

    OpenAIRE

    Santos,PA dos; Ludke,MCMM; Ludke,JV; Rabello,CBV; Santos,MJB dos; Torres,TR

    2015-01-01

    ABSTRACT These experiments were performed to determine the chemical composition, coefficients of nutrient and energy metabolizability, amino acid composition, and cytotoxicity of different castor oil meals subjected to different detoxification processes and added to the diet of Japanese quails. In the trial, 180 46-d-old female Japanese quails were distributed according to a completely randomized design into five treatments and with replicates of six bird each. The treatments consisted of fol...

  20. The Energy Deposition Pattern as the Unconventional Strangelet Signature and its Relevance to the Castor Calorimeter

    International Nuclear Information System (INIS)

    Angelis, A.L.S.; Bartke, J.; Gladysz-Dziadus, E.; Wlodarczyk, Z.

    1998-07-01

    It has been shown, by GEANT simulations, that the energy deposition pattern in deep calorimeters could be the spectacular and unconventional signature of different kinds of stable and unstable strangelets. The CASTOR calorimeter is shown to be the appropriate tool for detection of strongly penetrating objects, such as strangelets possibly produced in the baryon-rich region in central Pb-Pb collisions at LHC energies. (author)